Defining Cancer
Cancer is a term used for diseases in which abnormal cells divide without control and are able to invade other tissues. Cancer cells can spread to other parts of the body through the blood and lymph systems.
Cancer is not just one disease but many diseases. There are more than 100 different types of cancer. Most cancers are named for the organ or type of cell in which they start - for example, cancer that begins in the colon is called colon cancer; cancer that begins in basal cells of the skin is called basal cell carcinoma.
Cancer types can be grouped into broader categories. The main categories of cancer include:
Carcinoma - cancer that begins in the skin or in tissues that line or cover internal organs.
Sarcoma - cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.
Leukemia - cancer that starts in blood-forming tissue such as the bone marrow and causes large numbers of abnormal blood cells to be produced and enter the blood.
Lymphoma and myeloma - cancers that begin in the cells of the immune system.
Central nervous system cancers - cancers that begin in the tissues of the brain and spinal cord.
(For definitions of other cancer-related terms, see NCI's Dictionary of Cancer Terms.)
Origins of Cancer
All cancers begin in cells, the body's basic unit of life. To understand cancer, it's helpful to know what happens when normal cells become cancer cells.
The body is made up of many types of cells. These cells grow and divide in a controlled way to produce more cells as they are needed to keep the body healthy. When cells become old or damaged, they die and are replaced with new cells.
However, sometimes this orderly process goes wrong. The genetic material (DNA) of a cell can become damaged or changed, producing mutations that affect normal cell growth and division. When this happens, cells do not die when they should and new cells form when the body does not need them. The extra cells may form a mass of tissue called a tumor.
(Image from Understanding Cancer Series: Cancer.)
Not all tumors are cancerous; tumors can be benign or malignant.
Benign tumors aren't cancerous. They can often be removed, and, in most cases, they do not come back. Cells in benign tumors do not spread to other parts of the body.
Malignant tumors are cancerous. Cells in these tumors can invade nearby tissues and spread to other parts of the body. The spread of cancer from one part of the body to another is called metastasis.
Some cancers do not form tumors. For example, leukemia is a cancer of the bone marrow and blood.
Cancer Statistics
A new report from the nation's leading cancer organizations shows cancer death rates decreased on average 2.1 percent per year from 2002 through 2004, nearly twice the annual decrease of 1.1 percent per year from 1993 through 2002. (Read more about the Annual Report.)
Estimated new cases and deaths from cancer in the United States in 2008:
New cases: 1,437,180 (does not include nonmelanoma skin cancers)
Deaths: 565,650
NCI's Cancer Stat Fact Sheets provide frequently requested cancer statistics for a number of cancer types.
Additional Information
Find a type of cancer:
A to Z List of Cancers
Cancers by Body Location/System
Cancers that are diagnosed with the greatest frequency in the United States are listed below. (Read more about Common Cancer Types.)
Bladder Cancer Melanoma
Breast Cancer Non-Hodgkin Lymphoma
Colon and Rectal Cancer Pancreatic Cancer
Endometrial Cancer Prostate Cancer
Kidney (Renal Cell) Cancer Skin Cancer (Nonmelanoma)
Leukemia Thyroid Cancer
Lung Cancer
More cancer topics:
Cancer Prevention
Cancer Genetics
Cancer Causes and Risk Factors
Screening and Testing to Detect Cancer
Cancer Treatment
Coping with Cancer
Cancer Statistics
Clinical Trials
Cancer Publications
The risk of developing many types of cancer can be reduced by practicing healthy lifestyle habits, such as eating a healthy diet, getting regular exercise, and not smoking. Also, the sooner a cancer is found and treatment begins, the better the chances are that the treatment will be successful.
Contact Us for Help
NCI cancer information specialists can answer your questions about cancer and help you with quitting smoking. They can also help you with using this Web site and can tell you about NCI's printed and electronic materials. Contact us.
(National Cancer)
Kamis, 31 Juli 2008
Eat Right for Your Type
What It Is
The Eat Right for Your Type diet encourages people to eat certain foods and avoid others based on their blood type -- A, B, AB, or O.
Peter J. D'Adamo, ND, the author of Eat Right for Your Type: The Individualized Diet Solution to Staying Healthy, Living Longer & Achieving Your Ideal Weight, believes blood types affect the digestive system and that some foods good for people of one type are "dangerous" for another.
The Latest Diets
New diets and weight loss tricks pop up every month. Get the facts on how the new diets work and what's right.
Atkins
Best Life Diet
Biggest Loser
Cabbage Soup
Hallelujah Diet
Jenny Craig
NutriSystem
Ornish
South Beach
3 Day Diet
Weight Watchers
Zone
All Diets A-Z
Related to diet and weight loss Alli, apple cider vinegar, low carb diet, high protien diet, weight loss, metabolism, Mediterranean diet, diet pills, trans fat, BMI calculator, detox diet, diabetes diet, Body for Life
© 2008 WebMD, LLC. All rights reserved.
It goes further than that for D'Adamo, a naturopathic doctor, who believes that your blood type also determines your susceptibility to certain illnesses and how you should exercise.
Critics cite a lack of published evidence backing D'Adamo's blood type-based diet plan. "I know of no plausible rationale behind the diet," says John Foreyt, PhD, a researcher at the Baylor College of Medicine in Houston.
This diet may suit those enthusiastic about a plan that doesn't involve tracking calories or fat grams, while others may find it difficult to stay within the diet's confines, a challenge made greater if more than one person in a household follows the diet -- and has a different blood type.
What You Can Eat
What you can eat -- and how you exercise -- on this plan depends on who you are.
If you're blood type O ("for old," as in humanity's oldest blood line) your digestive tract retains the memory of ancient times, says D'Adamo, so you're metabolism will benefit from lean meats, poultry, and fish. You're advised to restrict grains, breads, legumes, and beans and to enjoy vigorous exercise.
Type A ("for agrarian") flourishes on vegetarian diets, "the inheritance of their more settled and less warlike farmer ancestors," says D'Adamo. The type A diet contains soy proteins, grains, and organic vegetables and encourages gentle exercise.
The nomadic blood type B has a tolerant digestive system and can enjoy low-fat dairy, meat, and produce but, among other things, should avoid wheat, corn, and lentils, D'Adamo says. If you're type B, it's recommended you exercise moderately.
The "modern" blood type AB has a sensitive digestive tract and should avoid chicken, beef, and pork but enjoy seafood, tofu, dairy, and most produce. The fitness regimen for ABs is calming exercises
The Eat Right for Your Type diet encourages people to eat certain foods and avoid others based on their blood type -- A, B, AB, or O.
Peter J. D'Adamo, ND, the author of Eat Right for Your Type: The Individualized Diet Solution to Staying Healthy, Living Longer & Achieving Your Ideal Weight, believes blood types affect the digestive system and that some foods good for people of one type are "dangerous" for another.
The Latest Diets
New diets and weight loss tricks pop up every month. Get the facts on how the new diets work and what's right.
Atkins
Best Life Diet
Biggest Loser
Cabbage Soup
Hallelujah Diet
Jenny Craig
NutriSystem
Ornish
South Beach
3 Day Diet
Weight Watchers
Zone
All Diets A-Z
Related to diet and weight loss Alli, apple cider vinegar, low carb diet, high protien diet, weight loss, metabolism, Mediterranean diet, diet pills, trans fat, BMI calculator, detox diet, diabetes diet, Body for Life
© 2008 WebMD, LLC. All rights reserved.
It goes further than that for D'Adamo, a naturopathic doctor, who believes that your blood type also determines your susceptibility to certain illnesses and how you should exercise.
Critics cite a lack of published evidence backing D'Adamo's blood type-based diet plan. "I know of no plausible rationale behind the diet," says John Foreyt, PhD, a researcher at the Baylor College of Medicine in Houston.
This diet may suit those enthusiastic about a plan that doesn't involve tracking calories or fat grams, while others may find it difficult to stay within the diet's confines, a challenge made greater if more than one person in a household follows the diet -- and has a different blood type.
What You Can Eat
What you can eat -- and how you exercise -- on this plan depends on who you are.
If you're blood type O ("for old," as in humanity's oldest blood line) your digestive tract retains the memory of ancient times, says D'Adamo, so you're metabolism will benefit from lean meats, poultry, and fish. You're advised to restrict grains, breads, legumes, and beans and to enjoy vigorous exercise.
Type A ("for agrarian") flourishes on vegetarian diets, "the inheritance of their more settled and less warlike farmer ancestors," says D'Adamo. The type A diet contains soy proteins, grains, and organic vegetables and encourages gentle exercise.
The nomadic blood type B has a tolerant digestive system and can enjoy low-fat dairy, meat, and produce but, among other things, should avoid wheat, corn, and lentils, D'Adamo says. If you're type B, it's recommended you exercise moderately.
The "modern" blood type AB has a sensitive digestive tract and should avoid chicken, beef, and pork but enjoy seafood, tofu, dairy, and most produce. The fitness regimen for ABs is calming exercises
Dark Chocolate Is Healthy Chocolate
By Daniel J. DeNoon
WebMD Health NewsAug. 27, 2003 -- Got high blood pressure? Try a truffle. Worried about heart disease? Buy a bon-bon.
It's the best medical news in ages. Studies in two prestigious scientific journals say dark chocolate -- but not white chocolate or milk chocolate -- is good for you.
Romance and Chocolate
From the WebMD community
How often do you say, "I love you," to your partner? Everyday... several times a day... my husband likes to hear it and he doesn't let me go to bed until I've said it even if we're fighting. – Katelya
Read more of your thoughts on love
Favorite Screen Romances
Sweet History of Chocolate
Science of Attraction: Feelings or Pheromones?
Today's Love Lingo
Video: Getting the Most Out of Your Relationship
Related to modern love Science of Attraction: Feelings or Pheromones?, Relationship in Distress? Tips to De-stress, When Mars and Venus Collide, Is Modern Life Giving Your Heart a Beating?
© 2008 WebMD, LLC. All rights reserved.
Dark Chocolate Lowers Blood Pressure
Dark chocolate -- not white chocolate -- lowers high blood pressure, say Dirk Taubert, MD, PhD, and colleagues at the University of Cologne, Germany. Their report appears in the Aug. 27 issue of The Journal of the American Medical Association.
But that's no license to go on a chocolate binge. Eating more dark chocolate can help lower blood pressure -- if you've reached a certain age and have mild high blood pressure, say the researchers. But you have to balance the extra calories by eating less of other things.
Antioxidants in Dark Chocolate
Dark chocolate -- but not milk chocolate or dark chocolate eaten with milk -- is a potent antioxidant, report Mauro Serafini, PhD, of Italy's National Institute for Food and Nutrition Research in Rome, and colleagues. Their report appears in the Aug. 28 issue of Nature. Antioxidants gobble up free radicals, destructive molecules that are implicated in heart disease and other ailments.
"Our findings indicate that milk may interfere with the absorption of antioxidants from chocolate ... and may therefore negate the potential health benefits that can be derived from eating moderate amounts of dark chocolate."
Translation: Say "Dark, please," when ordering at the chocolate counter. Don't even think of washing it down with milk. And if health is your excuse for eating chocolate, remember the word "moderate" as you nibble.
The Studies
Taubert's team signed up six men and seven women aged 55-64. All had just been diagnosed with mild high blood pressure -- on average, systolic blood pressure (the top number) of 153 and diastolic blood pressure (the bottom number) of 84.
Every day for two weeks, they ate a 100-gram candy bar and were asked to balance its 480 calories by not eating other foods similar in nutrients and calories. Half the patients got dark chocolate and half got white chocolate.
Those who ate dark chocolate had a significant drop in blood pressure (by an average of 5 points for systolic and an average of 2 points for diastolic blood pressure). Those who ate white chocolate did not.
In the second study, Serafini's team signed up seven healthy women and five healthy men aged 25-35. On different days they each ate 100 grams of dark chocolate by itself, 100 grams of dark chocolate with a small glass of whole milk, or 200 grams of milk chocolate.
An hour later, those who ate dark chocolate alone had the most total antioxidants in their blood. And they had higher levels of epicatechin, a particularly healthy compound found in chocolate. The milk chocolate eaters had the lowest epicatechin levels of all.
( Web MD Health News )
WebMD Health NewsAug. 27, 2003 -- Got high blood pressure? Try a truffle. Worried about heart disease? Buy a bon-bon.
It's the best medical news in ages. Studies in two prestigious scientific journals say dark chocolate -- but not white chocolate or milk chocolate -- is good for you.
Romance and Chocolate
From the WebMD community
How often do you say, "I love you," to your partner? Everyday... several times a day... my husband likes to hear it and he doesn't let me go to bed until I've said it even if we're fighting. – Katelya
Read more of your thoughts on love
Favorite Screen Romances
Sweet History of Chocolate
Science of Attraction: Feelings or Pheromones?
Today's Love Lingo
Video: Getting the Most Out of Your Relationship
Related to modern love Science of Attraction: Feelings or Pheromones?, Relationship in Distress? Tips to De-stress, When Mars and Venus Collide, Is Modern Life Giving Your Heart a Beating?
© 2008 WebMD, LLC. All rights reserved.
Dark Chocolate Lowers Blood Pressure
Dark chocolate -- not white chocolate -- lowers high blood pressure, say Dirk Taubert, MD, PhD, and colleagues at the University of Cologne, Germany. Their report appears in the Aug. 27 issue of The Journal of the American Medical Association.
But that's no license to go on a chocolate binge. Eating more dark chocolate can help lower blood pressure -- if you've reached a certain age and have mild high blood pressure, say the researchers. But you have to balance the extra calories by eating less of other things.
Antioxidants in Dark Chocolate
Dark chocolate -- but not milk chocolate or dark chocolate eaten with milk -- is a potent antioxidant, report Mauro Serafini, PhD, of Italy's National Institute for Food and Nutrition Research in Rome, and colleagues. Their report appears in the Aug. 28 issue of Nature. Antioxidants gobble up free radicals, destructive molecules that are implicated in heart disease and other ailments.
"Our findings indicate that milk may interfere with the absorption of antioxidants from chocolate ... and may therefore negate the potential health benefits that can be derived from eating moderate amounts of dark chocolate."
Translation: Say "Dark, please," when ordering at the chocolate counter. Don't even think of washing it down with milk. And if health is your excuse for eating chocolate, remember the word "moderate" as you nibble.
The Studies
Taubert's team signed up six men and seven women aged 55-64. All had just been diagnosed with mild high blood pressure -- on average, systolic blood pressure (the top number) of 153 and diastolic blood pressure (the bottom number) of 84.
Every day for two weeks, they ate a 100-gram candy bar and were asked to balance its 480 calories by not eating other foods similar in nutrients and calories. Half the patients got dark chocolate and half got white chocolate.
Those who ate dark chocolate had a significant drop in blood pressure (by an average of 5 points for systolic and an average of 2 points for diastolic blood pressure). Those who ate white chocolate did not.
In the second study, Serafini's team signed up seven healthy women and five healthy men aged 25-35. On different days they each ate 100 grams of dark chocolate by itself, 100 grams of dark chocolate with a small glass of whole milk, or 200 grams of milk chocolate.
An hour later, those who ate dark chocolate alone had the most total antioxidants in their blood. And they had higher levels of epicatechin, a particularly healthy compound found in chocolate. The milk chocolate eaters had the lowest epicatechin levels of all.
( Web MD Health News )
Cholesterol
Knowing the facts about cholesterol can reduce your risk for a heart attack or stroke. But understanding what cholesterol is and how it affects your health are only the beginning.
To keep your cholesterol under control:
schedule a screening
eat foods low in cholesterol and saturated fat and free of trans fat
maintain a healthy weight
be physically active
follow your healthcare professional's advice
How well do you know cholesterol? Take this brief quiz to test your cholesterol IQ.
Knowing the facts about cholesterol can help you improve your heart health and reduce your risk of heart disease.
Be prepared with these tips for ordering low-saturated fat, low-cholesterol meals at any restaurant.
This content is reviewed regularly. Last updated 04/03/08.
To keep your cholesterol under control:
schedule a screening
eat foods low in cholesterol and saturated fat and free of trans fat
maintain a healthy weight
be physically active
follow your healthcare professional's advice
How well do you know cholesterol? Take this brief quiz to test your cholesterol IQ.
Knowing the facts about cholesterol can help you improve your heart health and reduce your risk of heart disease.
Be prepared with these tips for ordering low-saturated fat, low-cholesterol meals at any restaurant.
This content is reviewed regularly. Last updated 04/03/08.
Sabtu, 19 Juli 2008
Awas, Bom Hipertensi!
Hipertensi, darah tinggi memang bukan pembunuh sejati. Tetapi ia digolongkan sebagai The Silent Killer (pembunuh diam-diam). Gejala penyakit ini tidak nyata, tapi harus tetap diwaspadai dan diobati sedini mungkin, karena hipertensi yang kronis dan diabaikan dapat membawa malapetaka tiba-tiba, serangan jantung dan stroke.
Di Amerika, setiap tahun hampir separuh jumlah kematian disebabkan oleh faktor kelebihan konsumsi garam (natrium/sodium). Sumber utama natrium di sana adalah garam dapur. Namun di Indonesia, selain garam dapur dan ikan asin, sumber lain yang lebih potensial adalah monosodium glutamat (MSG/vetsin).
Kadar natrium dalam 1 gram garam dapur setara dengan kadar natrium yang terkandung dalam 3 gram
(1 sendok teh) MSG/vetsin. Satu gram garam dapur bisa membuat 1 mangkuk sup menjadi asin.
Sebaliknya 3 gram MSG tidak terasa asin, justru terasa gurih, sehingga secara tidak sadar dengan
mudah bisa kebablasan konsumsi MSG dan keracunan. Ini belum terhitung dari paparan MSG dalam berbagai makanan lainnya, yang membuat konsumen secara perlahan mulai toleran dan menimbukan
efek kecanduan. Sehingga bila MSG diberikan dalam jumlah sedikit, tidak akan terasa gurihnya. Jika kebiasaan ini berlangsung berkepanjangan (10–20 tahun), tidak mustahil rakyat Indonesia akan mengalami gejala hipertensi akibat keracunan MSG.
Kenapa Bisa Darah Tinggi?
Seseorang dinyatakan mengidap hipertensi bila tekanan sistoliknya mencapai di atas 140 mmHg dan tekanan diastolik di atas 90 mmHg. Tekanan sistolik adalah tekanan maksimum dimana jantung berkontraksi dan memompa darah ke luar, sedangkan tekanan diastolik adalah tekanan dimana jantung sedang mengalami relaksasi, menerima curahan darah dari pembuluh darah perifer.
Ada dua bentuk hipertensi. Bentuk esensial, yang penyebabnya belum diketahui, kemungkinan karena faktor keturunan. Bentuk lannya, hipertensi yang disebabkan oleh faktor lingkungan yang biasanya sangat erat hubungannya dengan pola makan kurang baik. Faktor makanan yang sangat berpengaruh adalah kelebihan lemak (obesitas), konsumsi garam dapur yang tinggi, merokok serta minum alkohol.
Di Amerika, setiap tahun hampir separuh jumlah kematian disebabkan oleh faktor kelebihan konsumsi garam (natrium/sodium). Sumber utama natrium di sana adalah garam dapur. Namun di Indonesia, selain garam dapur dan ikan asin, sumber lain yang lebih potensial adalah monosodium glutamat (MSG/vetsin).
Kadar natrium dalam 1 gram garam dapur setara dengan kadar natrium yang terkandung dalam 3 gram
(1 sendok teh) MSG/vetsin. Satu gram garam dapur bisa membuat 1 mangkuk sup menjadi asin.
Sebaliknya 3 gram MSG tidak terasa asin, justru terasa gurih, sehingga secara tidak sadar dengan
mudah bisa kebablasan konsumsi MSG dan keracunan. Ini belum terhitung dari paparan MSG dalam berbagai makanan lainnya, yang membuat konsumen secara perlahan mulai toleran dan menimbukan
efek kecanduan. Sehingga bila MSG diberikan dalam jumlah sedikit, tidak akan terasa gurihnya. Jika kebiasaan ini berlangsung berkepanjangan (10–20 tahun), tidak mustahil rakyat Indonesia akan mengalami gejala hipertensi akibat keracunan MSG.
Kenapa Bisa Darah Tinggi?
Seseorang dinyatakan mengidap hipertensi bila tekanan sistoliknya mencapai di atas 140 mmHg dan tekanan diastolik di atas 90 mmHg. Tekanan sistolik adalah tekanan maksimum dimana jantung berkontraksi dan memompa darah ke luar, sedangkan tekanan diastolik adalah tekanan dimana jantung sedang mengalami relaksasi, menerima curahan darah dari pembuluh darah perifer.
Ada dua bentuk hipertensi. Bentuk esensial, yang penyebabnya belum diketahui, kemungkinan karena faktor keturunan. Bentuk lannya, hipertensi yang disebabkan oleh faktor lingkungan yang biasanya sangat erat hubungannya dengan pola makan kurang baik. Faktor makanan yang sangat berpengaruh adalah kelebihan lemak (obesitas), konsumsi garam dapur yang tinggi, merokok serta minum alkohol.
Anak Sulit Makan Berakibat Fatal
Sulit makan pada anak dapat berakibat fatal bila dipicu oleh penyakit atau kelainan tertentu. Kesulitan ini bisa seperti anak tidak mau menelan makanan dan cuma ditahan dalam mulut, bahkan dikeluarkan lagi, juga menolak atau melawan pada waktu makan. Mungkin bisa juga makan terlalu sedikit atau sebaliknya, hanya mau makan jenis makanan tertentu misalnya susu, cepat bosan dengan makanan yang disajikan dan lain-lain
Gangguan tersebut dapat menimpa semua kelompok usia anak, dari mulai bayi yang baru lahir sampai akhir masa anak-anak (berkisar 18 tahun). Namun jenis, penyebab, derajat dan lamanya diperkirakan berbeda-beda. Derajat kesulitan makan mungkin sederhana, cuma berlangsung singkat seperti kurang nafsu makan, seperti yang biasa ditemukan ketika anak menderita penyakit infeksi akut. Kesulitan makan pun bisa berlangsung lama dan berat, sehingga berdampak fatal.
Memang kelainan tersebut dapat disebabkan oleh suatu penyakit tertentu, tetapi bisa juga muncul dari multifaktor. Faktor ini dibagi menjadi tiga kelompok, yaitu nutrisi (kemampuan untuk mengonsumsi makanan tertentu), kelainan organik, dan gangguan jiwa. Akibatnya, kesehatan tubuh, tumbuh kembang dan aktivitas sehari-hari anak menjadi terhambat. Misalnya pada kelainan yang singkat, anak menjadi kehabisan energi akut, sampai pingsan atau kejang-kejang, karena tak makan beberapa hari.
Sedangkan pada anak yang tidak menyukai sayuran atau buah-buahan dapat terkena kekurangan vitamin A. Anak pun bisa tekena anemia dan defisiensi besi, jika hanya mengonsumsi susu murni, sehingga berdampak buruk pada kekebalan dan kecerdasan otak. Kekurangan makan dalam waktu lama dapat menghambat pertumbuhan serta perkembangan, pada bayi disebut dengan ‘gagal tumbuh’ atau terjadi malnutrisi energi protein pada balita
Gangguan tersebut dapat menimpa semua kelompok usia anak, dari mulai bayi yang baru lahir sampai akhir masa anak-anak (berkisar 18 tahun). Namun jenis, penyebab, derajat dan lamanya diperkirakan berbeda-beda. Derajat kesulitan makan mungkin sederhana, cuma berlangsung singkat seperti kurang nafsu makan, seperti yang biasa ditemukan ketika anak menderita penyakit infeksi akut. Kesulitan makan pun bisa berlangsung lama dan berat, sehingga berdampak fatal.
Memang kelainan tersebut dapat disebabkan oleh suatu penyakit tertentu, tetapi bisa juga muncul dari multifaktor. Faktor ini dibagi menjadi tiga kelompok, yaitu nutrisi (kemampuan untuk mengonsumsi makanan tertentu), kelainan organik, dan gangguan jiwa. Akibatnya, kesehatan tubuh, tumbuh kembang dan aktivitas sehari-hari anak menjadi terhambat. Misalnya pada kelainan yang singkat, anak menjadi kehabisan energi akut, sampai pingsan atau kejang-kejang, karena tak makan beberapa hari.
Sedangkan pada anak yang tidak menyukai sayuran atau buah-buahan dapat terkena kekurangan vitamin A. Anak pun bisa tekena anemia dan defisiensi besi, jika hanya mengonsumsi susu murni, sehingga berdampak buruk pada kekebalan dan kecerdasan otak. Kekurangan makan dalam waktu lama dapat menghambat pertumbuhan serta perkembangan, pada bayi disebut dengan ‘gagal tumbuh’ atau terjadi malnutrisi energi protein pada balita
Anak Kelebihan Beban?
Anak-anak yang memiliki masa depan cerah merupakan impian semua orang tua. Oleh karena itu, anak-anak jaman sekarang memiliki begitu banyak kegiatan di luar sekolah, di antaranya pelajaran les pelajaran (les matematika, les komputer, les bahasa inggris, dll) da, les tambahan (les piano, les balet, les melukis, les renang, les bela diri, dll). Namun jadwal yang padat seperti itu dapat membuat Anak menjadi kelebihan beban, sehingga dapat membuat mereka stres dan merasa tertekan.
1 di antara 4 anak usia sekolah menderita stres akibat aktivitas yang berlebihan. Anak-anak perlu agar mereka dapat bereksperimen dengan aktivitas yang dimilikinya, kemudian dibebaskan untuk memilih mana yang disukainya. Pakar berpendapat agar anak tidak memiliki 3 kegiatan pada suatu waktu, seperti 1 kegiatan sosial, 1 kegiatan olahraga, dan 1 kegiatan untuk meningkatkan keterampilan yang dimilikinya.
Namun jika Anda menemukan anak merasa tertekan, lakukan :
Monitor tingkah laku anak Perhatikan setiap tingkah laku anak Anda. Sikap kasar, perubahan perasaan yang mencolok (sebentar ia akan merasa murung, kemudian gembira, lalu kembali murung), prestasi menurun, perubahan pola makan, sulit tidur merupakan tanda-tanda anak stres.
Susun kembali agenda anak
Tanyakan kepada anak aktivitas apa yang mereka sukai. Kemudian tanyakanlah kepada diri Anda sendiri, apakah Anda lebih menyukai anak melakukan kegiatan-kegiatan tersebut dibanding anak Anda sendiri.
Berilah anak waktu untuk bermain dan menikmati masa kecil mereka
Sisihkan paling sedikit 1 jam setiap hari dan beberapa jam di akhir pekan agar anak-anak dapat bermain.
1 di antara 4 anak usia sekolah menderita stres akibat aktivitas yang berlebihan. Anak-anak perlu agar mereka dapat bereksperimen dengan aktivitas yang dimilikinya, kemudian dibebaskan untuk memilih mana yang disukainya. Pakar berpendapat agar anak tidak memiliki 3 kegiatan pada suatu waktu, seperti 1 kegiatan sosial, 1 kegiatan olahraga, dan 1 kegiatan untuk meningkatkan keterampilan yang dimilikinya.
Namun jika Anda menemukan anak merasa tertekan, lakukan :
Monitor tingkah laku anak Perhatikan setiap tingkah laku anak Anda. Sikap kasar, perubahan perasaan yang mencolok (sebentar ia akan merasa murung, kemudian gembira, lalu kembali murung), prestasi menurun, perubahan pola makan, sulit tidur merupakan tanda-tanda anak stres.
Susun kembali agenda anak
Tanyakan kepada anak aktivitas apa yang mereka sukai. Kemudian tanyakanlah kepada diri Anda sendiri, apakah Anda lebih menyukai anak melakukan kegiatan-kegiatan tersebut dibanding anak Anda sendiri.
Berilah anak waktu untuk bermain dan menikmati masa kecil mereka
Sisihkan paling sedikit 1 jam setiap hari dan beberapa jam di akhir pekan agar anak-anak dapat bermain.
Jumat, 18 Juli 2008
Biologi Hati & Kandung Empedu
Hati dan kandung empedu terletak di perut kanan bagian atas, dan keduanya dihubungkan oleh suatu saluran yang dikenal sebagai duktus biliaris (saluran empedu). Hati merupakan organ kompleks yang melaksanakan berbagai fungsi vital, mulai dari mengatur kadar zat kimia dalam tubuh sampai menghasilkan zat-zat pembekuan darah. Sedangkan kandung empedu merupakan tempat penyimpanan empedu, yaitu cairan pencernaan yang dihasilkan oleh hati.
HATI
Hati merupakan organ tubuh yang paling besar dan paling kompleks. Salah satu fungsinya adalah menghancurkan zat-zat yang berbahaya yang diserap dari usus atau bagian tubuh lainnya, kemudian membuangnya sebagai zat yang tidak berbahaya ke dalam empedu atau darah. Zat di dalam empedu akan masuk ke dalam usus lalu dibuang melalui tinja. Zat di dalam darah disaring oleh ginjal dan dibuang melalui air kemih.
Hati menghasilkan separuh dari kolesterol tubuh, sisanya berasal dari makanan. Sekitar 80% kolesterol yang dibuat di hati digunakan untuk membuat empedu. Kolesterol juga diperlukan untuk membuat hormon-hormon tertentu, seperti hormon estrogen, testosteron, dan adrenal.
Hati juga merubah zat-zat di dalam makanan menjadi karbohidrat, protein, dan lemak. Gula disimpan di dalam hati sebagai glikogen dan kemudian dipecah serta dilepaskan ke dalam aliran darah sebagai glukosa, sesuai dengan kebutuhan tubuh (misalnya ketika kadar gula darah terlalu rendah).
Fungsi lain dari hati adalah membuat berbagai senyawa penting, terutama protein, yang digunakan tubuh untuk menjalankan fungsinya.
Ada dua macam kelainan fungsi hati yang utama, yaitu:
Kelainan yang disebabkan oleh gangguan fungsi sel-sel di dalam hati (misalnya sirosis atau hepatitis)
Kelainan yang disebabkan oleh adanya penyumbatan aliran empedu dari hati melalui saluran empedu (misalnya batu empedu atau kanker)
KANDUNG EMPEDU
Kandung empedu merupakan kantong otot kecil yang berfungsi untuk menyimpan empedu, yaitu cairan pencernaan berwarna kuning kehijauan yang dihasilkan oleh hati. Jika kita makan, kandung empedu akan berkontraksi dan mengosongkan empedu ke dalam usus untuk membantu pencernaan lemak dan vitamin-vitamin tertentu.
Empedu itu sendiri terdiri dari:
Garam-garam empedu
Elektrolit
Pigmen empedu (misalnya bilirubin)
Kolesterol
Lemak
Fungsi empedu adalah untuk membuang limbah tubuh tertentu (terutama pigmen hasil pemecahan sel darah merah dan kelebihan kolesterol) serta membantu pencernaan dan penyerapan lemak.
Garam empedu dapat meningkatkan kelarutan kolesterol, lemak, dan vitamin yang larut dalam lemak, sehingga membantu penyerapannya dari usus. Hemoglobin yang berasal dari penghancuran sel darah merah akan diubah menjadi bilirubin (pigmen utama dalam empedu) dan dibuang ke dalam empedu. Berbagai protein yang memegang peranan penting dalam fungsi empedu juga disekresi dalam empedu.
HATI
Hati merupakan organ tubuh yang paling besar dan paling kompleks. Salah satu fungsinya adalah menghancurkan zat-zat yang berbahaya yang diserap dari usus atau bagian tubuh lainnya, kemudian membuangnya sebagai zat yang tidak berbahaya ke dalam empedu atau darah. Zat di dalam empedu akan masuk ke dalam usus lalu dibuang melalui tinja. Zat di dalam darah disaring oleh ginjal dan dibuang melalui air kemih.
Hati menghasilkan separuh dari kolesterol tubuh, sisanya berasal dari makanan. Sekitar 80% kolesterol yang dibuat di hati digunakan untuk membuat empedu. Kolesterol juga diperlukan untuk membuat hormon-hormon tertentu, seperti hormon estrogen, testosteron, dan adrenal.
Hati juga merubah zat-zat di dalam makanan menjadi karbohidrat, protein, dan lemak. Gula disimpan di dalam hati sebagai glikogen dan kemudian dipecah serta dilepaskan ke dalam aliran darah sebagai glukosa, sesuai dengan kebutuhan tubuh (misalnya ketika kadar gula darah terlalu rendah).
Fungsi lain dari hati adalah membuat berbagai senyawa penting, terutama protein, yang digunakan tubuh untuk menjalankan fungsinya.
Ada dua macam kelainan fungsi hati yang utama, yaitu:
Kelainan yang disebabkan oleh gangguan fungsi sel-sel di dalam hati (misalnya sirosis atau hepatitis)
Kelainan yang disebabkan oleh adanya penyumbatan aliran empedu dari hati melalui saluran empedu (misalnya batu empedu atau kanker)
KANDUNG EMPEDU
Kandung empedu merupakan kantong otot kecil yang berfungsi untuk menyimpan empedu, yaitu cairan pencernaan berwarna kuning kehijauan yang dihasilkan oleh hati. Jika kita makan, kandung empedu akan berkontraksi dan mengosongkan empedu ke dalam usus untuk membantu pencernaan lemak dan vitamin-vitamin tertentu.
Empedu itu sendiri terdiri dari:
Garam-garam empedu
Elektrolit
Pigmen empedu (misalnya bilirubin)
Kolesterol
Lemak
Fungsi empedu adalah untuk membuang limbah tubuh tertentu (terutama pigmen hasil pemecahan sel darah merah dan kelebihan kolesterol) serta membantu pencernaan dan penyerapan lemak.
Garam empedu dapat meningkatkan kelarutan kolesterol, lemak, dan vitamin yang larut dalam lemak, sehingga membantu penyerapannya dari usus. Hemoglobin yang berasal dari penghancuran sel darah merah akan diubah menjadi bilirubin (pigmen utama dalam empedu) dan dibuang ke dalam empedu. Berbagai protein yang memegang peranan penting dalam fungsi empedu juga disekresi dalam empedu.
Mengelola Diabetes
Tujuan kita mengelola Diabetes adalah peningkatan kualitas hidup para penyandang Diabetes dan untuk jangka pendek menghilangkan keluhan atau gejala, mempertahankan rasa nyaman dan tercapainya target pengendalian glukosa darah. Sedangkan tujuan jangka panjangnya adalah untuk mencegah dan menghambat terjadinya komplikasi. Semua ini akan menurunkan angka kesakitan dan resiko kematian akibat Diabetes. Konsep penanganan penyakit kardiometabolik yang saat ini dianut, menyarankan pengendalian glukosa darah bersama-sama dengan pengendalian tekanan darah dan lemak darah.
Studi terbesar dan terlama yang dilakukan di Inggris, yaitu United Kingdom Prospective Diabetes Study (UKPDS), menunjukkan bahwa mengendalikan kadar glukosa darah dapat menurunkan risiko terjadinya komplikasi pada retina (selaput jala) mata yang dapat berakhir dengan kebutaan, komplikasi ginjal, dan komplikasi syaraf. Studi ini juga mendapatkan bahwa mengendalikan tekanan darah akan menurunkan risiko terjadinya stroke, kematian, gagal jantung, komplikasi ginjal, retina. Menurutnya kadar lipid darah) istilah awamnya: kolesterol) akan mengurangi risiko terjadinya serangan jantung, stroke, dan amputasi kaki.
Target parameter dari kadar / keadaan yang diharapkan :
Glukosa darah puasa (80 - 99 mg/dL)
Glukosa darah 2 jam sesudah makan (80 - 144 mg/dL)
Hemoglobin A1C (< 6.5 %)
Kolesterol total (< 200 mg/dL)
Kolesterol LDL (< 100 mg/dL)
Kolesterol HDL (wanita : > 50 mg/dL, pria : > 40 mg/dL)
Trigliserida (< 150 mg/dL)
Indeks massa tubuh (18.5 - 22.9 kg/m2)
Tekanan Darah (< atayu sama dengan 130 / 80 mmHg)
Indeks massa tubuh (IMT) adalah hasil pembagian berat badan dalam kilogram dengan kuadrat dari tinggi badan dalam meter (BB / (TB)2)
Sumber : www.kalbenutritionals.com
Studi terbesar dan terlama yang dilakukan di Inggris, yaitu United Kingdom Prospective Diabetes Study (UKPDS), menunjukkan bahwa mengendalikan kadar glukosa darah dapat menurunkan risiko terjadinya komplikasi pada retina (selaput jala) mata yang dapat berakhir dengan kebutaan, komplikasi ginjal, dan komplikasi syaraf. Studi ini juga mendapatkan bahwa mengendalikan tekanan darah akan menurunkan risiko terjadinya stroke, kematian, gagal jantung, komplikasi ginjal, retina. Menurutnya kadar lipid darah) istilah awamnya: kolesterol) akan mengurangi risiko terjadinya serangan jantung, stroke, dan amputasi kaki.
Target parameter dari kadar / keadaan yang diharapkan :
Glukosa darah puasa (80 - 99 mg/dL)
Glukosa darah 2 jam sesudah makan (80 - 144 mg/dL)
Hemoglobin A1C (< 6.5 %)
Kolesterol total (< 200 mg/dL)
Kolesterol LDL (< 100 mg/dL)
Kolesterol HDL (wanita : > 50 mg/dL, pria : > 40 mg/dL)
Trigliserida (< 150 mg/dL)
Indeks massa tubuh (18.5 - 22.9 kg/m2)
Tekanan Darah (< atayu sama dengan 130 / 80 mmHg)
Indeks massa tubuh (IMT) adalah hasil pembagian berat badan dalam kilogram dengan kuadrat dari tinggi badan dalam meter (BB / (TB)2)
Sumber : www.kalbenutritionals.com
Selasa, 15 Juli 2008
Tips Mengurangi Nyeri Tumbuh Gigi Pada Batita Anda
Tumbuh gigi seringkali sering disertai oleh rasa nyeri. Hal ini menjadikan anak menjadi rewel. Bagaimana cara menguranginya? Simak saja tips berikut di bawah ini.
Gosok dan pijat gusi bayi dengan kain halus yang dililitkan pada jari Anda. Pada umumnya bayi menyukai jika Anda melakukan hal ini.
Dinginkan gigi dengan memberikannya teether atau dot yang sudah didinginkan sebelumnya di dalam lemari es. Atau Anda dapat membasuh gigi dengan menggunakan kain basah yang telah direndam di dalam air es. Dengan begitu, maka rasa gatal dan nyeri di giginya akan berkurang.
Mainan yang digigit-gigit anak dapat membuat anak merasa nyaman, karena rasa nyeri di gusi teralihkan.
Jika anak merasa kesakitan selama 3 atau 4 hari, segeralah periksakan ia pada dokter. Mungkin saja kerewelannya disebabkan oleh hal lain, bukan karena gigi yang tidak mau keluar.
Gosok dan pijat gusi bayi dengan kain halus yang dililitkan pada jari Anda. Pada umumnya bayi menyukai jika Anda melakukan hal ini.
Dinginkan gigi dengan memberikannya teether atau dot yang sudah didinginkan sebelumnya di dalam lemari es. Atau Anda dapat membasuh gigi dengan menggunakan kain basah yang telah direndam di dalam air es. Dengan begitu, maka rasa gatal dan nyeri di giginya akan berkurang.
Mainan yang digigit-gigit anak dapat membuat anak merasa nyaman, karena rasa nyeri di gusi teralihkan.
Jika anak merasa kesakitan selama 3 atau 4 hari, segeralah periksakan ia pada dokter. Mungkin saja kerewelannya disebabkan oleh hal lain, bukan karena gigi yang tidak mau keluar.
Keringat
Keringat tak selamanya memalukan. Siapa sangka, si bau selama ini tak diinginkan justru bisa jadi senjata untuk memikat lawan jenis. Ya, bau keringat pria terbukti merupakan pembangkit gairah yang tak kalah ampuh dari coklat atau afrodisiak lainnya.
Kehabisan untuk memikat lawan jenis? Bagi para pria, tak usah jauh-jauh mencari ’love potion’ ampuh untuk membuat wanita bertekuk lutut. Andalkan senjata yang melekat ditubuh Pria. Jangan salah sangka dahulu karena kita tidak sedang berbicara mengenai ’ senjata’ yang satu itu. Bau keringatlah yang dimaksud disini.
Para peneliti di University of Calivornia, Berkely, AS memastikan, menghirup bau keringat pria bisa membuat gairah seksual wanita meningkat. Diiringi peningkatan produksi hormon tertentu serta percepatan detak jantung.
Pada studi ini, 48 orang wanita usia rata-rata 21 tahun diminta menghirup 1 tabung berisi zat androstadienone, salah satu komponen dalam keringat, air ludah maupun sperma pria. Mereka diminta menghirupnya sebanyak 20 kali. Hasilnya, dalam waktu 15 menit saja terjadi lonjakan hormon kortisol di dalam tubh wanita. Hormon kortisol di dalam tubuh wanita. Hormon kortisol adalah hormon yang berperan dalam membuat perasaan sigap dan senang. Hormon ini juga berperan dalam membatu manusia merespons stres. Lonjakan yang terjadi bahkan bertahan hingga satu jam.
Para wanita juga dilaporkan mengalami peningkatan rangsangan seksual, perbaikan suasana hati juga peningkatan tekanan darah, denyut jantung pernapasan. Bagaimana bau zat ini? Sulit dilukiskan. Tapi yang jelas bernuansa musky atau tajam dan ’jantan’.
Mereka yang ambil bagian dalam studi ini adalah wanita heteroseksual. Ini memang disenggaja, karena para ahli khawatir wanita penyuka sesama jenis akan merespons keringat pria secara berbeda.
Studi yang dipublikasikan di Journal of Neuroscience edisi Maret 2007 ini untuk pertama kalinya memberi bukti nyata bahwa tubuh manusia mengeluarkan bau yang dapat mempengaruhi hormon lawan jenis.
Ada manfaat lain dari temuan ini selain dalam urusan rangsang-merangsang. Menghirup kortisol bisa jadi alternatif bagi pasien yang menderita penyakit akibat kekurangan hormon kortisol, seperti pasien Addison’s disease ( penyakit berciri lemah tubuh, tekanan darah rendah dan perubahan kulit menjadi kecokelatan). Selama ini, kortisol diberikan dalam bentuk pil yang memiliki efek samping seperti osteoporosis, pertambahan berat badan dan gangguan mood
Kehabisan untuk memikat lawan jenis? Bagi para pria, tak usah jauh-jauh mencari ’love potion’ ampuh untuk membuat wanita bertekuk lutut. Andalkan senjata yang melekat ditubuh Pria. Jangan salah sangka dahulu karena kita tidak sedang berbicara mengenai ’ senjata’ yang satu itu. Bau keringatlah yang dimaksud disini.
Para peneliti di University of Calivornia, Berkely, AS memastikan, menghirup bau keringat pria bisa membuat gairah seksual wanita meningkat. Diiringi peningkatan produksi hormon tertentu serta percepatan detak jantung.
Pada studi ini, 48 orang wanita usia rata-rata 21 tahun diminta menghirup 1 tabung berisi zat androstadienone, salah satu komponen dalam keringat, air ludah maupun sperma pria. Mereka diminta menghirupnya sebanyak 20 kali. Hasilnya, dalam waktu 15 menit saja terjadi lonjakan hormon kortisol di dalam tubh wanita. Hormon kortisol di dalam tubuh wanita. Hormon kortisol adalah hormon yang berperan dalam membuat perasaan sigap dan senang. Hormon ini juga berperan dalam membatu manusia merespons stres. Lonjakan yang terjadi bahkan bertahan hingga satu jam.
Para wanita juga dilaporkan mengalami peningkatan rangsangan seksual, perbaikan suasana hati juga peningkatan tekanan darah, denyut jantung pernapasan. Bagaimana bau zat ini? Sulit dilukiskan. Tapi yang jelas bernuansa musky atau tajam dan ’jantan’.
Mereka yang ambil bagian dalam studi ini adalah wanita heteroseksual. Ini memang disenggaja, karena para ahli khawatir wanita penyuka sesama jenis akan merespons keringat pria secara berbeda.
Studi yang dipublikasikan di Journal of Neuroscience edisi Maret 2007 ini untuk pertama kalinya memberi bukti nyata bahwa tubuh manusia mengeluarkan bau yang dapat mempengaruhi hormon lawan jenis.
Ada manfaat lain dari temuan ini selain dalam urusan rangsang-merangsang. Menghirup kortisol bisa jadi alternatif bagi pasien yang menderita penyakit akibat kekurangan hormon kortisol, seperti pasien Addison’s disease ( penyakit berciri lemah tubuh, tekanan darah rendah dan perubahan kulit menjadi kecokelatan). Selama ini, kortisol diberikan dalam bentuk pil yang memiliki efek samping seperti osteoporosis, pertambahan berat badan dan gangguan mood
Kegunaan Air Kelapa
Air kelapa memang banyak manfaatnya. Selain untuk kesehatan, air kelapa juga bermanfaat sebagai ramuan untuk kecantikan.
Menghilangkan jerawat
Tuang segelas air kelapa dalam wadah berisi parutan 3 ruas kunyit. Biarkan semalam dalam lemari es. Setelah itu, bubuhkan tiga sendok teh bubuk cendana ke dalamnya. Simpan lagi selama tiga hari, kemudian saring ramuan dengan kain kasa. Oleskan sari larutan tersebut pada wajah yang berjerawat dua kali sehari sampai jerawat lenyap.
Mencegah kerutan wajah dini
Wajah Anda berkerut? Basuhlah wajah dengan air kelapa, sesering Anda suka. Niscaya wajah Anda akan kencang.
Mencegah ubanan
Anda berusia muda namun rambut banyak ditumbuhi uban? Coba larutkan satu sendok teh garam dapur dalam air kelapa hijau segar. Gunakan setelah keramas. Setelah itu, biarkan selama beberapa menit di kepala sambil dipijat-pijat. Bilas dengan air bersih.
Meningkatkan gairah seksual
Kurang bergairah? Campurkan air kelapa muda dengan sedikit madu alam, lalu minum. Ramuan ini berkhasiat merangsang pusat-pusat seksual tubuh.
Suara merdu
Agar suara Anda lebih merdu, coba minum segelas air kelapa muda yang telah diembunkan selama semalam. Lakukan selama seminggu.
Menghilangkan jerawat
Tuang segelas air kelapa dalam wadah berisi parutan 3 ruas kunyit. Biarkan semalam dalam lemari es. Setelah itu, bubuhkan tiga sendok teh bubuk cendana ke dalamnya. Simpan lagi selama tiga hari, kemudian saring ramuan dengan kain kasa. Oleskan sari larutan tersebut pada wajah yang berjerawat dua kali sehari sampai jerawat lenyap.
Mencegah kerutan wajah dini
Wajah Anda berkerut? Basuhlah wajah dengan air kelapa, sesering Anda suka. Niscaya wajah Anda akan kencang.
Mencegah ubanan
Anda berusia muda namun rambut banyak ditumbuhi uban? Coba larutkan satu sendok teh garam dapur dalam air kelapa hijau segar. Gunakan setelah keramas. Setelah itu, biarkan selama beberapa menit di kepala sambil dipijat-pijat. Bilas dengan air bersih.
Meningkatkan gairah seksual
Kurang bergairah? Campurkan air kelapa muda dengan sedikit madu alam, lalu minum. Ramuan ini berkhasiat merangsang pusat-pusat seksual tubuh.
Suara merdu
Agar suara Anda lebih merdu, coba minum segelas air kelapa muda yang telah diembunkan selama semalam. Lakukan selama seminggu.
Kekurangan Asupan Gizi Pada Anak Akan Menyebabkan Tingkat Kecerdasan Anak menurun
Sebuah penelitian membuktikan adanya keterkaitan antara tubuh pendek dan tingkat kecerdasan. Bila sejak awal sudah tidak ada keseimbangan antara berat dan tinggi badan, maka akan berpengaruh pada pembentukan otak. Oleh sebab itu, kebutuhan gizi bayi sejak janin sampai usia lima tahun harus terpenuhi secara baik.
Anak yang perkembangannya sangat lambat disebabkan oleh pembentukan otak dan tubuhnya tidak baik akibat gizi yang buruk. Berarti hal paling penting adalah pemenuhan gizi bayi sejak dalam kandungan sampai berusia lima tahun dan bila tidak terpenuhi, pertumbuhan otak dan tubuhnya tidak baik. Anak dengan tubuh pendek menunjukkan status gizi pada masa lalunya sudah kronis. Namun begitu, sampai usia 18 tahun pun asupan gizi masih penting untuk pertumbuhan fisik anak. Jadi jika tubuh seseorang kurus, hal ini dipengaruhi oleh keadaan gizi pada saat itu.
Sekitar 62% anak di perkotaan memiliki tinggi badan normal dari segi umur, sedangkan anak di pedesaan hanya 49%. Maka disimpulkan bahwa anak di perkotaan memiliki keadaan gizi yang lebih baik dibandingkan anak di pedesaan. Meskipun demikian, obesitas (gemuk sekali) pada anak di perkotaan cenderung lebih tinggi dibanding anak di pedesaan. Namun, masalah itu mulai meningkat bukan saja di perkotaan, melainkan juga di pedesaan.
Atas dasar tersebut, program perbaikan gizi sekarang harus diubah dengan memperhatikan faktor yang terkait dengan pola hidup penduduk di perkotaan maupun pedesaan.
Sejumlah studi di Filipina, Jamaika, dan negara lainnya membuktikan adanya hubungan yang sangat bermakna antara tinggi badan dan kemampuan belajar. Bahkan, pemberian makanan tambahan pada anak bertubuh pendek berusia 9-24 bulan akan mampu meningkatkan kemampuan belajar anak ketika berusia 7-8 tahun. Dibuktikan pula dari beberapa studi bidang ekonomi di Ghana maupun Pakistan mengenai pentingnya gizi untuk mendukung pembangunan.
Anak yang perkembangannya sangat lambat disebabkan oleh pembentukan otak dan tubuhnya tidak baik akibat gizi yang buruk. Berarti hal paling penting adalah pemenuhan gizi bayi sejak dalam kandungan sampai berusia lima tahun dan bila tidak terpenuhi, pertumbuhan otak dan tubuhnya tidak baik. Anak dengan tubuh pendek menunjukkan status gizi pada masa lalunya sudah kronis. Namun begitu, sampai usia 18 tahun pun asupan gizi masih penting untuk pertumbuhan fisik anak. Jadi jika tubuh seseorang kurus, hal ini dipengaruhi oleh keadaan gizi pada saat itu.
Sekitar 62% anak di perkotaan memiliki tinggi badan normal dari segi umur, sedangkan anak di pedesaan hanya 49%. Maka disimpulkan bahwa anak di perkotaan memiliki keadaan gizi yang lebih baik dibandingkan anak di pedesaan. Meskipun demikian, obesitas (gemuk sekali) pada anak di perkotaan cenderung lebih tinggi dibanding anak di pedesaan. Namun, masalah itu mulai meningkat bukan saja di perkotaan, melainkan juga di pedesaan.
Atas dasar tersebut, program perbaikan gizi sekarang harus diubah dengan memperhatikan faktor yang terkait dengan pola hidup penduduk di perkotaan maupun pedesaan.
Sejumlah studi di Filipina, Jamaika, dan negara lainnya membuktikan adanya hubungan yang sangat bermakna antara tinggi badan dan kemampuan belajar. Bahkan, pemberian makanan tambahan pada anak bertubuh pendek berusia 9-24 bulan akan mampu meningkatkan kemampuan belajar anak ketika berusia 7-8 tahun. Dibuktikan pula dari beberapa studi bidang ekonomi di Ghana maupun Pakistan mengenai pentingnya gizi untuk mendukung pembangunan.
Tinggi Badan Anak
Bayi pada umumnya memiliki berat badan normal antara 2500 hingga 3000 gram, dengan panjang badan antara 48 hingga 50 cm. Selanjutnya, pertumbuhan tinggi dan berat badan bayi tidak akan sama. Menurut seorang dokter dari divisi Endokrinologi, pertumbuhan terbagi menjadi tiga tahap.
Pertama, dimulai dari bayi lahir hingga ia berusia tiga tahun. Pada tahun pertama, pertambahan tinggi badan mencapai 1, 5 kali panjang lahir. Usia dua tahun, rata-rata anak tumbuh sebanyak 6 hingga 10 cm per tahunnya. Tahap kedua adalah tahap anak-anak yang akan berakhir ketika anak memasuki pubertas (usia 6 hingga 12 tahun). Pada tahap ini penambahan tinggi badan anak mencapai 5 hingga 7 cm per tahunnya. Di tahap ini anak akan kelihatan memanjang, mengurus, dan perutnya tidak buncit lagi. Tahap terakhir adalah tahap pubertas (12 hingga 18 tahun) yang ditandai dengan percepatan dalam pertumbuhan karena pengaruh hormon seksual. Pertumbuhan tinggi badan anak remaja akan melaju dengan cepat, dan kemudian secara perlahan akan terhenti. Pada anak perempuan yang masa pubertasnya terjadi lebih awal, tinggi badannya akan mencapai 8 cm per tahun. Sedangkan pada anak laki-laki akan mencapai 10 cm per tahun. Bila tahap ini berakhir, maka berakhir pula proses pertumbuhan anak.
Jika tinggi anak berada pada atau melebihi 97 per seratus dari batas garis maksimal tinggi seseorang pada kurva pertumbuhan yang berlaku pada populasi tertentu, maka anak dapat dikatakan memiliki perawakan yang tinggi. Tinggi badan rata-rata anak Indonesia mulai dari ia lahir hingga berusia 5 tahun, adalah 48 hingga 120 cm.
Faktor genetik adalah elemen dasar penenti tinggi seseorang. Seorang anak akan mencapai tinggi badannya dengan gen penentu tinggi badan yang diwarisinya. Jika orang tuanya memiliki perawakan yang tinggi, maka secara genetis anak cenderung memiliki perawakan yang tinggi pula. Namun sering kita jumpai, anak lebih tinggi dari orang tuanya. Hal ini bisa saja terjadi karena dari kedua orang tua kita mengenal konsep Potensi Tingi Genetik (seorang anak dilahirkan berpotensi atau akan mencapai tinggi dewasa tertentu yang berada dalam rentang waktu tertentu).
Selain faktor genetik, faktor gizi juga harus diperhatikan, terutama sejak dalam kandungan. Beberapa zat gizi yang penting, seperti protein, lemak, vitamin (vitamin A dan D), mineral (zat besi, kalsium, seng, dan yodium) turut membantu dalam proses pertumbuhan anak.
Beberapa jenis hormon yang berperan penting dalam proses pertumbuhan tinggi dan berat anak, antara lain hormon pertumbuhan, hormon tiroid, dan hormon seks.Hormon pertumbuhan berfungsi untuk merangsang pertumbuhan tulang. Hormon tiroid dibutuhkan untuk membantu melancarkan proses metabolisme dalam tubuh. Sedangkan hormon seks terdiri dari hormon estrogen, progesteron, dan androgen, bertugas dalam proses pematangan seksual.
Faktor lingkungan, seperti imunisasi, kasih sayang yang cukup, dan kebutuhan ekonomi juga sangat mendukung pertumbuhan tinggi seseorang. Imunisasi sangat penting untuk melindungi anak dari berbagai penyakit yang dapat menghambar pertumbuhan fisiknya. Kasih sayang yang kurang akan memberi dampak kehilangan nafsu makan pada anak. Demikian pula halnya dengan kekurangan dalam kebutuhan ekonomi akan berdampak pada ketersediaan pangan yang mengandung gizi seimbang.
Pertama, dimulai dari bayi lahir hingga ia berusia tiga tahun. Pada tahun pertama, pertambahan tinggi badan mencapai 1, 5 kali panjang lahir. Usia dua tahun, rata-rata anak tumbuh sebanyak 6 hingga 10 cm per tahunnya. Tahap kedua adalah tahap anak-anak yang akan berakhir ketika anak memasuki pubertas (usia 6 hingga 12 tahun). Pada tahap ini penambahan tinggi badan anak mencapai 5 hingga 7 cm per tahunnya. Di tahap ini anak akan kelihatan memanjang, mengurus, dan perutnya tidak buncit lagi. Tahap terakhir adalah tahap pubertas (12 hingga 18 tahun) yang ditandai dengan percepatan dalam pertumbuhan karena pengaruh hormon seksual. Pertumbuhan tinggi badan anak remaja akan melaju dengan cepat, dan kemudian secara perlahan akan terhenti. Pada anak perempuan yang masa pubertasnya terjadi lebih awal, tinggi badannya akan mencapai 8 cm per tahun. Sedangkan pada anak laki-laki akan mencapai 10 cm per tahun. Bila tahap ini berakhir, maka berakhir pula proses pertumbuhan anak.
Jika tinggi anak berada pada atau melebihi 97 per seratus dari batas garis maksimal tinggi seseorang pada kurva pertumbuhan yang berlaku pada populasi tertentu, maka anak dapat dikatakan memiliki perawakan yang tinggi. Tinggi badan rata-rata anak Indonesia mulai dari ia lahir hingga berusia 5 tahun, adalah 48 hingga 120 cm.
Faktor genetik adalah elemen dasar penenti tinggi seseorang. Seorang anak akan mencapai tinggi badannya dengan gen penentu tinggi badan yang diwarisinya. Jika orang tuanya memiliki perawakan yang tinggi, maka secara genetis anak cenderung memiliki perawakan yang tinggi pula. Namun sering kita jumpai, anak lebih tinggi dari orang tuanya. Hal ini bisa saja terjadi karena dari kedua orang tua kita mengenal konsep Potensi Tingi Genetik (seorang anak dilahirkan berpotensi atau akan mencapai tinggi dewasa tertentu yang berada dalam rentang waktu tertentu).
Selain faktor genetik, faktor gizi juga harus diperhatikan, terutama sejak dalam kandungan. Beberapa zat gizi yang penting, seperti protein, lemak, vitamin (vitamin A dan D), mineral (zat besi, kalsium, seng, dan yodium) turut membantu dalam proses pertumbuhan anak.
Beberapa jenis hormon yang berperan penting dalam proses pertumbuhan tinggi dan berat anak, antara lain hormon pertumbuhan, hormon tiroid, dan hormon seks.Hormon pertumbuhan berfungsi untuk merangsang pertumbuhan tulang. Hormon tiroid dibutuhkan untuk membantu melancarkan proses metabolisme dalam tubuh. Sedangkan hormon seks terdiri dari hormon estrogen, progesteron, dan androgen, bertugas dalam proses pematangan seksual.
Faktor lingkungan, seperti imunisasi, kasih sayang yang cukup, dan kebutuhan ekonomi juga sangat mendukung pertumbuhan tinggi seseorang. Imunisasi sangat penting untuk melindungi anak dari berbagai penyakit yang dapat menghambar pertumbuhan fisiknya. Kasih sayang yang kurang akan memberi dampak kehilangan nafsu makan pada anak. Demikian pula halnya dengan kekurangan dalam kebutuhan ekonomi akan berdampak pada ketersediaan pangan yang mengandung gizi seimbang.
Ethics take center stage at fertility conference
By Michael Kahn
updated 2:08 p.m. ET July 7, 2008
BARCELONA - A U.S. researcher's argument that twins should be the goal of in vitro fertilization drew opposition from many researchers on Monday who warned of the risks of multiple pregnancies.
Presenting a study at the annual meeting of the European Society of Human Reproduction and Embryology, Norbert Gleicher said twins are a solution for infertile couples who want more than one child.
His review of previous studies found that it is cheaper for couples to have twins because it can cut the number of treatments and the risk is not significantly greater for mother and child
updated 2:08 p.m. ET July 7, 2008
BARCELONA - A U.S. researcher's argument that twins should be the goal of in vitro fertilization drew opposition from many researchers on Monday who warned of the risks of multiple pregnancies.
Presenting a study at the annual meeting of the European Society of Human Reproduction and Embryology, Norbert Gleicher said twins are a solution for infertile couples who want more than one child.
His review of previous studies found that it is cheaper for couples to have twins because it can cut the number of treatments and the risk is not significantly greater for mother and child
New test can help spot best embryos: researchers
By Michael Kahn
updated 1:00 p.m. ET July 8, 2008
BARCELONA - The same infrared technology that measures fat content in milk can more accurately predict which embryos have the best chance of resulting in a pregnancy, fertility experts said on Tuesday.
Speaking at the European Society of Human Reproduction and Embryology, the researchers estimated their new technique for couples attempting in vitro fertilization could help boost pregnancy rates by about 10 percent to 15 percent.
In vitro fertilization or IVF is the procedure commonly known as the test-tube baby treatment.
updated 1:00 p.m. ET July 8, 2008
BARCELONA - The same infrared technology that measures fat content in milk can more accurately predict which embryos have the best chance of resulting in a pregnancy, fertility experts said on Tuesday.
Speaking at the European Society of Human Reproduction and Embryology, the researchers estimated their new technique for couples attempting in vitro fertilization could help boost pregnancy rates by about 10 percent to 15 percent.
In vitro fertilization or IVF is the procedure commonly known as the test-tube baby treatment.
Babies from frozen embryos are just as healthy
BARCELONA, Spain - More evidence is emerging that babies conceived in test tubes might be just as healthy as those conceived naturally, researchers said Tuesday.
Two studies presented at a meeting of the European Society of Human Reproduction and Embryology found that in-vitro fertilization and the freezing of embryos did not significantly increase the babies' chances of medical problems.
"These procedures are relatively safe and patients shouldn't be overly concerned," said Dr. Christopher Barratt, a professor of reproductive medicine at the University of Dundee in Britain.
Two studies presented at a meeting of the European Society of Human Reproduction and Embryology found that in-vitro fertilization and the freezing of embryos did not significantly increase the babies' chances of medical problems.
"These procedures are relatively safe and patients shouldn't be overly concerned," said Dr. Christopher Barratt, a professor of reproductive medicine at the University of Dundee in Britain.
Sabtu, 12 Juli 2008
Kegunaan Buah Mahkota Dewa
PARA pakar phitopharmaka ( ahli tanaman obat ) sepakat bahwa Indonesia memang kaya potensi tanaman obat-obatan. Kekayaan plasma nuftah kita kedua terbesar di dunia setelah Brasil. Namun anehnya, dalam perkembangan percaturan bisnis phitofharmaka, kita malah kalah terkenal dibandingkan dengan Cina. Negara "Tirai Bambu" ini telah membangun citra bisnis obat-obatan herbal ini, konon sudah berumur lebih dari 6.000 tahun.
Hal ini dibuktikan dengan adanya buku-buku pengobatan kuno yang telah berumur ribuan tahun. Salah satu buku pengobatan kuno yang terkenal dan terlengkap adalah Huang Ti Nei Ching ( Pengobatan internal Kaisar Kuning ). Buku pengobatan kuno ini diperkirakan dibuat pada abad ke-3 sebelum masehi.
Para pakar mengatakan, dari sejumlah 40.000 jenis tanamana di dunia, 30.000 jenis di antaranya terdapat di Indonesia. Dari sejumlah itu sampai sejauh ini tidak kurang dari 1.375 jenis tanaman terdeteksi sebagai tanaman obat-obatan. Namun, yang sudah dimanfaatkan baru sekira 400 jenis dan yang masih diteliti hanya 10 jenis saja.
Melihat angka yang tertera itu, kita sangat prihatin sekali. Karena kendati kita kaya dengan sumber daya tanaman obat-obatan, penggunaannya kecil sekali. Di Indonesia, penggunaannya masih setengah-setengah. Sementara itu, di negara Eropa dan AS saat ini justru sedang gencar-gencarnya mengadakan penelitian dan langsung ke tingkat pemakain.
Tampaknya back to nature oleh orang-orang Barat sudah bukan semboyan lagi. Mereka justru melihat bahwa pemakaian bahan kimia sintetik untuk obat banyak menimbulkan masalah dan biayanya pun lebih tinggi. Untuk memasok kebutuhan bahan baku, mereka mengimpor dari Indonesia, Cina, Thailand, dan Malaysia yang cukup luas hutan-hutannya.
Hal lain yang menarik untuk diungkapkan dalam tulisan ini adalah terdapat banyak bahan-bahan obat alami asli Indonesia yang entah bagaimana mulanya, malah lebih terkenal di negara lain. Untuk ini, saya sebut satu saja, yaitu tanaman "Mahkota Dewa", di negeri "Tirai Bambu" banyak dijadikan sebagai bahan dasar obat tradisional mereka. Di Cina tanaman, yang habitat alamnya berasal dari Papua (Irian Jaya) ini dikenal dengan nama lain yaitu "Shian Thno".
Racun untuk pengobatan
Menurut H. Sarah Kriswanti, penduduk KPAD Geger Kalong Bandung, yang banyak mengoleksi tanaman obat-obatan mengungkapkan, Mahkota Dewa adalah tanaman aperduk yang bisa mencapai ketinggian lima meter. Ia dapat tumbuh dari ketinggian 10 m dpl ( di atas permukaan laut ) hingga 1.200 m dpl.
Bahan yang dapat dimanfaatkan untuk obat adalah bagian buahnya yang apabila telah tua benar-benar sangat menarik untuk dimakan. Padahal, buah itu sungguh sangat beracun apabila tidak diolah dahulu. Setelah diolah dikeringkan, buah irisan keringan itu bisa ditambah dengan campuran lain untuk memperkuat pengobatannya. Misalnya saja, agar tidak menjadi beser (kencing terus-menerus) bisa dicampur dengan daun mimba, dsb.
Diungkapkan Ny. Sarah, banyak peminat racikan "Mahkota Dewa" yang sudah divonis dokter setelah mencoba racikannya malah jadi sembuh total. "Dalam hubungan ini, saya sendiri selalu menganjurkan agar setelah meminum ramuannnya selalu konsultasi dengan dokter untuk memantau perkembangan kesehatannya. Dahulu, pada awalnya saya hanya hobi saja mengumpulkan tanaman obat-obatan untuk kebutuhan keluarga. Namun, setelah satu dua orang memohon pertolongannya untuk memberikan racikan tanaman obatnya. Eeeehhh, ternyata dia sembuh oleh tanaman obat itu.
Atas pertanyaan, ia juga mengungkapkan banyak pasien-pasien yang telah sembuh ahirnya membeli bibit tanaman obat hasil koleksinya. Selain membeli tanaman bibit, mereka juga memberi obat herbal yang sudah dikeringkan. "Karena banyak juga orang yang datang, tidak sabar menunggu tumbuh besarnya koleksi tanaman mereka. Untuk ini, mereka membeli langsung racikan koleksi tanaman obat saya," katanya serius.
Di rumahnya yang munggil, dari sejak halaman muka hingga ke belakang, dikoleksi tanaman obat, selain Mahkota Dewa, ada sambiloto, Kunyit putih, Jahe Merah, Pegagan atau antatan, dan Mimba. Namun, di atara tanaman-tanaman itu yang sangat dibanggakan adalah tanaman "Mahkota Dewa". Tanaman ini memang jadi andalannya karena fungsi penyembuhannya sangat luas dan banyak.
Beberapa jenis penyakit yang telah disembuhkan a.l. penyakit kanker ( bermacam-macam ). Banyak komentar dari para pasien penyakit ganas ini, mereka lebih memilih pangobatan dengan "Mahkota Dewa" dibandingkan dengan menggunakan bahan kimia. Hasilnya ternyata lebih baik dan cespleng.
Selain kanker, juga penyakait jantung, lever, diabetes, darah tinggi, rematik, atau asam urat tinggi, penyakit ginjal. Bahkan untuk penambah stamina, tidak kalah dengan obat-obat suplemen yang sudah ada sekarang. Ramuan "Mahkota Dewa" dicampur dengan ramuan jahe merah ternyata mampu membangkitkan "si Tole" yang telah lama tidur lelap. Banyak lagi jenis penyakit yang berhasil dilawan "Mahkota Dewa" ini, tapi bila ditulis di halamam koran kita ini mungkin tidak akan termuat.
Itulah sedikit gambaran bahwa ternyata tanaman liar yang ada di Bumi Pertiwi ini ternyata bisa mendunia dan lebih manjur dari obat-obat kimia yang jauh lebih berbahaya. Semoga bermanfaat. (Dedi Riskomar)***
Sumber :Sumber : http://www.pikiran-rakyat.com/cetak/0103/07/0603.htm
Mahkota Dewa atau Phaleria macrocarpa adalah tanaman asli Indonesia yang terbukti empiris menyembuhkan segala penyakit, dari yang ringan sampai berat.
Masyarakat sadar akan pentingnya “Back To Nature”, terlihat banyaknya penelitian tanaman pusaka para dewa ini. Tim peneliti Cancer Research Group Fak.Farmasi UGM dibawah naungan Dr. Edy Meiyanto, MSi, Apt. membuktikan ekstrak air daging buah Mahkota Dewa menghambat pertumbuhan kanker (pendekatan DNA supercoil).
Tidak mengherankan tanaman ini mulai diburu masyarakat guna menjaga kesehatan dan penyembuhan penyakit.
Khasiat Mahkota Dewa :
Secara empiris mampu menyembuhkan lever, kanker, jantung, lemah syahwat, rhematik, diabetes mellitus, ketagihan narkoba, asam urat, darah tinggi, dan penyakit ringan (seperti EKSIM, JERAWAT, DAN LUKA GIGITAN SERANGGA) bisa disembuhkan dengan pohon ini.
Mahkota dewa adalah tanaman asli Indonesia. Habitat asalnya di tanah Papua. Namun, entah bagaimana caranya, tanaman ini masuk ke Keraton Mangkunegara di Solo dan Keraton Yogyakarta. Di kedua tempat itu mahkota dewa dikenal sebagai tanaman obat. Dulu memang hanya kedua keraton itu yang mengenal khasiat mahkota dewa untuk keperluan pengobatan.
Ukuran :
Sosoknya berupa pohon perdu. Tajuk pohon bercabang-cabang. Ketinggiannya sekitar 1,5 - 2,5 meter. Namun, jika dibiarkan, bisa mencapai lima meter. Mahkota dewa bisa sampai berumur puluhan tahun. Tingkat produktivitasnya mampu dipertahankan sampai usia 10 hingga 20 tahun. Pohon mahkota dewa terdiri dari akar, batang, daun, bunga, dan buah. Akarnya berupa akar tunggang. Panjang akarnya bisa sampai 100 cm. Akar ini belum terbukti bisa digunakan untuk pengobatan.
Kandungan & Manfaat : Masalah yang mengganjal terhadap pemakaian mahkota dewa sebagai tanaman obat adalah terbatasnya pembuktian-pembuktian ilmiah akan kegunaan pohon ini. Selama ini pembuktian yang ada sebagian terbesar masih berupa pembuktian empiris, pembuktian yang hanya berdasarkan pada pengalaman pengguna.
Literatur-literatur yang membahasnya pun sangat terbatas. R. Broto Sudibyo, Kepala Bidang Pelayanan Sentra Pengembangan dan Penerapan Pengobatan Tradisional (SP3T) Rumah Sakit Bethesda, Yogyakarta, menguatkan keterbatasan literatur ini. Dalam literatur kuno pun, keterangan mengenai mahkota dewa sangat terbatas. Hanya kegunaan biji buah yang bermanfaat sebagai bahan baku obat luar, misalnya untuk obat kudis, yang dibahas.
Dari penelitian ilmiah yang sangat terbatas itu diketahui bahwa mahkota dewa memiliki kandungan kimia yang kaya. Itu pun belum semuanya terungkap. Dalam daun dan kulit buahnya terkandung ALKALOID, SAPONIN, dan FLAVONOID. Selain itu, di dalam daunnya juga terkandung POLIFENOL.
Seorang ahli farmakologi dari Fakultas Kedokteran UGM, dr. Regina Sumastuti, berhasil membuktikan bahwa mahkota dewa mengandung ZAT ANTIHISTAMIN. Zat ini merupakan penangkal alergi. Dengan begitu, dari sudut pandang ilmiah, mahkota dewa bisa menyembuhkan aneka penyakit alergi yang disebabkan histamin, seperti biduren, gatal-gatal, selesma, dan sesak napas. Penelitian dr. Regina juga membuktikan bahwa mahkota dewa mampu berperan seperti oxytosin atau sintosinon yang dapat memacu kerja otot rahim sehingga persalinan berlangsung lebih lancar. Pembuktian empiris yang ada cukup banyak. Kasusnya juga berbeda-beda, dari yang berat sampai yang sepele. Kasus Tuti di atas hanyalah salah satu contoh.
Sampai saat ini banyak penyakit yang berhasil disembuhkan dengan mahkota dewa. Beberapa penyakit berat (seperti SAKIT LEVER, KANKER, SAKIT JANTUNG, KENCING MANIS, ASAM URAT, REUMATIK, SAKIT GINJAL, TEKANAN DARAH TINGGI, LEMAH SYAHWAT DAN KETAGIHAN NARKOBA) dan penyakit ringan (seperti EKSIM, JERAWAT, DAN LUKA GIGITAN SERANGGA) bisa disembuhkan dengan pohon ini.
Pembuktian empiris juga dapat ditemui di sebuah pesantren yang getol menangani korban obat-obat psikotropika. Bahkan, beberapa orang dokter yang mengidap penyakit cukup gawat pun sudah membuktikan khasiat mahkota dewa.
PERHATIAN:
IBU-IBU YANG HAMIL MUDA DILARANG MENGKONSUMSI MAHKOTA DEWA. KARENA, MAHKOTA DEWA DAPAT MENINGKATKAN KONTRAKSI OTOT RAHIM SEHINGGA SANGAT BERBAHAYA BAGI KONDISI KEHAMILAN
Hal ini dibuktikan dengan adanya buku-buku pengobatan kuno yang telah berumur ribuan tahun. Salah satu buku pengobatan kuno yang terkenal dan terlengkap adalah Huang Ti Nei Ching ( Pengobatan internal Kaisar Kuning ). Buku pengobatan kuno ini diperkirakan dibuat pada abad ke-3 sebelum masehi.
Para pakar mengatakan, dari sejumlah 40.000 jenis tanamana di dunia, 30.000 jenis di antaranya terdapat di Indonesia. Dari sejumlah itu sampai sejauh ini tidak kurang dari 1.375 jenis tanaman terdeteksi sebagai tanaman obat-obatan. Namun, yang sudah dimanfaatkan baru sekira 400 jenis dan yang masih diteliti hanya 10 jenis saja.
Melihat angka yang tertera itu, kita sangat prihatin sekali. Karena kendati kita kaya dengan sumber daya tanaman obat-obatan, penggunaannya kecil sekali. Di Indonesia, penggunaannya masih setengah-setengah. Sementara itu, di negara Eropa dan AS saat ini justru sedang gencar-gencarnya mengadakan penelitian dan langsung ke tingkat pemakain.
Tampaknya back to nature oleh orang-orang Barat sudah bukan semboyan lagi. Mereka justru melihat bahwa pemakaian bahan kimia sintetik untuk obat banyak menimbulkan masalah dan biayanya pun lebih tinggi. Untuk memasok kebutuhan bahan baku, mereka mengimpor dari Indonesia, Cina, Thailand, dan Malaysia yang cukup luas hutan-hutannya.
Hal lain yang menarik untuk diungkapkan dalam tulisan ini adalah terdapat banyak bahan-bahan obat alami asli Indonesia yang entah bagaimana mulanya, malah lebih terkenal di negara lain. Untuk ini, saya sebut satu saja, yaitu tanaman "Mahkota Dewa", di negeri "Tirai Bambu" banyak dijadikan sebagai bahan dasar obat tradisional mereka. Di Cina tanaman, yang habitat alamnya berasal dari Papua (Irian Jaya) ini dikenal dengan nama lain yaitu "Shian Thno".
Racun untuk pengobatan
Menurut H. Sarah Kriswanti, penduduk KPAD Geger Kalong Bandung, yang banyak mengoleksi tanaman obat-obatan mengungkapkan, Mahkota Dewa adalah tanaman aperduk yang bisa mencapai ketinggian lima meter. Ia dapat tumbuh dari ketinggian 10 m dpl ( di atas permukaan laut ) hingga 1.200 m dpl.
Bahan yang dapat dimanfaatkan untuk obat adalah bagian buahnya yang apabila telah tua benar-benar sangat menarik untuk dimakan. Padahal, buah itu sungguh sangat beracun apabila tidak diolah dahulu. Setelah diolah dikeringkan, buah irisan keringan itu bisa ditambah dengan campuran lain untuk memperkuat pengobatannya. Misalnya saja, agar tidak menjadi beser (kencing terus-menerus) bisa dicampur dengan daun mimba, dsb.
Diungkapkan Ny. Sarah, banyak peminat racikan "Mahkota Dewa" yang sudah divonis dokter setelah mencoba racikannya malah jadi sembuh total. "Dalam hubungan ini, saya sendiri selalu menganjurkan agar setelah meminum ramuannnya selalu konsultasi dengan dokter untuk memantau perkembangan kesehatannya. Dahulu, pada awalnya saya hanya hobi saja mengumpulkan tanaman obat-obatan untuk kebutuhan keluarga. Namun, setelah satu dua orang memohon pertolongannya untuk memberikan racikan tanaman obatnya. Eeeehhh, ternyata dia sembuh oleh tanaman obat itu.
Atas pertanyaan, ia juga mengungkapkan banyak pasien-pasien yang telah sembuh ahirnya membeli bibit tanaman obat hasil koleksinya. Selain membeli tanaman bibit, mereka juga memberi obat herbal yang sudah dikeringkan. "Karena banyak juga orang yang datang, tidak sabar menunggu tumbuh besarnya koleksi tanaman mereka. Untuk ini, mereka membeli langsung racikan koleksi tanaman obat saya," katanya serius.
Di rumahnya yang munggil, dari sejak halaman muka hingga ke belakang, dikoleksi tanaman obat, selain Mahkota Dewa, ada sambiloto, Kunyit putih, Jahe Merah, Pegagan atau antatan, dan Mimba. Namun, di atara tanaman-tanaman itu yang sangat dibanggakan adalah tanaman "Mahkota Dewa". Tanaman ini memang jadi andalannya karena fungsi penyembuhannya sangat luas dan banyak.
Beberapa jenis penyakit yang telah disembuhkan a.l. penyakit kanker ( bermacam-macam ). Banyak komentar dari para pasien penyakit ganas ini, mereka lebih memilih pangobatan dengan "Mahkota Dewa" dibandingkan dengan menggunakan bahan kimia. Hasilnya ternyata lebih baik dan cespleng.
Selain kanker, juga penyakait jantung, lever, diabetes, darah tinggi, rematik, atau asam urat tinggi, penyakit ginjal. Bahkan untuk penambah stamina, tidak kalah dengan obat-obat suplemen yang sudah ada sekarang. Ramuan "Mahkota Dewa" dicampur dengan ramuan jahe merah ternyata mampu membangkitkan "si Tole" yang telah lama tidur lelap. Banyak lagi jenis penyakit yang berhasil dilawan "Mahkota Dewa" ini, tapi bila ditulis di halamam koran kita ini mungkin tidak akan termuat.
Itulah sedikit gambaran bahwa ternyata tanaman liar yang ada di Bumi Pertiwi ini ternyata bisa mendunia dan lebih manjur dari obat-obat kimia yang jauh lebih berbahaya. Semoga bermanfaat. (Dedi Riskomar)***
Sumber :Sumber : http://www.pikiran-rakyat.com/cetak/0103/07/0603.htm
Mahkota Dewa atau Phaleria macrocarpa adalah tanaman asli Indonesia yang terbukti empiris menyembuhkan segala penyakit, dari yang ringan sampai berat.
Masyarakat sadar akan pentingnya “Back To Nature”, terlihat banyaknya penelitian tanaman pusaka para dewa ini. Tim peneliti Cancer Research Group Fak.Farmasi UGM dibawah naungan Dr. Edy Meiyanto, MSi, Apt. membuktikan ekstrak air daging buah Mahkota Dewa menghambat pertumbuhan kanker (pendekatan DNA supercoil).
Tidak mengherankan tanaman ini mulai diburu masyarakat guna menjaga kesehatan dan penyembuhan penyakit.
Khasiat Mahkota Dewa :
Secara empiris mampu menyembuhkan lever, kanker, jantung, lemah syahwat, rhematik, diabetes mellitus, ketagihan narkoba, asam urat, darah tinggi, dan penyakit ringan (seperti EKSIM, JERAWAT, DAN LUKA GIGITAN SERANGGA) bisa disembuhkan dengan pohon ini.
Mahkota dewa adalah tanaman asli Indonesia. Habitat asalnya di tanah Papua. Namun, entah bagaimana caranya, tanaman ini masuk ke Keraton Mangkunegara di Solo dan Keraton Yogyakarta. Di kedua tempat itu mahkota dewa dikenal sebagai tanaman obat. Dulu memang hanya kedua keraton itu yang mengenal khasiat mahkota dewa untuk keperluan pengobatan.
Ukuran :
Sosoknya berupa pohon perdu. Tajuk pohon bercabang-cabang. Ketinggiannya sekitar 1,5 - 2,5 meter. Namun, jika dibiarkan, bisa mencapai lima meter. Mahkota dewa bisa sampai berumur puluhan tahun. Tingkat produktivitasnya mampu dipertahankan sampai usia 10 hingga 20 tahun. Pohon mahkota dewa terdiri dari akar, batang, daun, bunga, dan buah. Akarnya berupa akar tunggang. Panjang akarnya bisa sampai 100 cm. Akar ini belum terbukti bisa digunakan untuk pengobatan.
Kandungan & Manfaat : Masalah yang mengganjal terhadap pemakaian mahkota dewa sebagai tanaman obat adalah terbatasnya pembuktian-pembuktian ilmiah akan kegunaan pohon ini. Selama ini pembuktian yang ada sebagian terbesar masih berupa pembuktian empiris, pembuktian yang hanya berdasarkan pada pengalaman pengguna.
Literatur-literatur yang membahasnya pun sangat terbatas. R. Broto Sudibyo, Kepala Bidang Pelayanan Sentra Pengembangan dan Penerapan Pengobatan Tradisional (SP3T) Rumah Sakit Bethesda, Yogyakarta, menguatkan keterbatasan literatur ini. Dalam literatur kuno pun, keterangan mengenai mahkota dewa sangat terbatas. Hanya kegunaan biji buah yang bermanfaat sebagai bahan baku obat luar, misalnya untuk obat kudis, yang dibahas.
Dari penelitian ilmiah yang sangat terbatas itu diketahui bahwa mahkota dewa memiliki kandungan kimia yang kaya. Itu pun belum semuanya terungkap. Dalam daun dan kulit buahnya terkandung ALKALOID, SAPONIN, dan FLAVONOID. Selain itu, di dalam daunnya juga terkandung POLIFENOL.
Seorang ahli farmakologi dari Fakultas Kedokteran UGM, dr. Regina Sumastuti, berhasil membuktikan bahwa mahkota dewa mengandung ZAT ANTIHISTAMIN. Zat ini merupakan penangkal alergi. Dengan begitu, dari sudut pandang ilmiah, mahkota dewa bisa menyembuhkan aneka penyakit alergi yang disebabkan histamin, seperti biduren, gatal-gatal, selesma, dan sesak napas. Penelitian dr. Regina juga membuktikan bahwa mahkota dewa mampu berperan seperti oxytosin atau sintosinon yang dapat memacu kerja otot rahim sehingga persalinan berlangsung lebih lancar. Pembuktian empiris yang ada cukup banyak. Kasusnya juga berbeda-beda, dari yang berat sampai yang sepele. Kasus Tuti di atas hanyalah salah satu contoh.
Sampai saat ini banyak penyakit yang berhasil disembuhkan dengan mahkota dewa. Beberapa penyakit berat (seperti SAKIT LEVER, KANKER, SAKIT JANTUNG, KENCING MANIS, ASAM URAT, REUMATIK, SAKIT GINJAL, TEKANAN DARAH TINGGI, LEMAH SYAHWAT DAN KETAGIHAN NARKOBA) dan penyakit ringan (seperti EKSIM, JERAWAT, DAN LUKA GIGITAN SERANGGA) bisa disembuhkan dengan pohon ini.
Pembuktian empiris juga dapat ditemui di sebuah pesantren yang getol menangani korban obat-obat psikotropika. Bahkan, beberapa orang dokter yang mengidap penyakit cukup gawat pun sudah membuktikan khasiat mahkota dewa.
PERHATIAN:
IBU-IBU YANG HAMIL MUDA DILARANG MENGKONSUMSI MAHKOTA DEWA. KARENA, MAHKOTA DEWA DAPAT MENINGKATKAN KONTRAKSI OTOT RAHIM SEHINGGA SANGAT BERBAHAYA BAGI KONDISI KEHAMILAN
Jumat, 11 Juli 2008
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(Reference : Healthy School Campaign
Your contribution can make a real impact on our ability to continue to raise issues, raise standards and raise awareness of school environmental health and wellness.
The Healthy Schools Campaign is a not-for-profit, tax-exempt organization. (FEIN # 36-4308068.) Gifts are tax deductible to the extent allowed by law.
Make a donation!
Your contribution will help make schools healthier places to learn and work. Click here to donate now »
Honor someone with a donation!
We will send your honoree(s) a card letting them know that a gift has been made in their honor.For a gift of $25 or more, we will send your honoree a copy of Fresh Choices, a cookbook written by HSC founder Rochelle Davis. Click here to honor someone with a donation »
(Reference : Healthy School Campaign
Kamis, 10 Juli 2008
Stem cell
Stem cells are cells found in most, if not all, multi-cellular organisms. They are characterized by the ability to renew themselves through mitotic cell division and differentiating into a diverse range of specialized cell types. Research in the stem cell field grew out of findings by Canadian scientists Ernest A. McCulloch and James E. Till in the 1960s.[1][2] The two broad types of mammalian stem cells are: embryonic stem cells that are found in blastocysts, and adult stem cells that are found in adult tissues. In a developing embryo, stem cells can differentiate into all of the specialized embryonic tissues. In adult organisms, stem cells and progenitor cells act as a repair system for the body, replenishing specialized cells, but also maintain the normal turnover of regenerative organs, such as blood, skin or intestinal tissues.
As stem cells can be grown and transformed into specialized cells with characteristics consistent with cells of various tissues such as muscles or nerves through cell culture, their use in medical therapies has been proposed. In particular, embryonic cell lines, autologous embryonic stem cells generated through therapeutic cloning, and highly plastic adult stem cells from the umbilical cord blood or bone marrow are touted as promising candidates.[3]
Contents [hide]
1 Properties of stem cells
1.1 Potency definitions
1.2 Identifying stem cells
2 Embryonic stem cells
3 Adult stem cells
4 Lineage
5 Treatments
6 Controversy surrounding human embryonic stem cell research
7 Key stem cell research events
8 Stem cell funding & policy debate in the US
9 See also
10 References
11 External links
[edit] Properties of stem cells
The classical definition of a stem cell requires that it possess two properties:
Self-renewal - the ability to go through numerous cycles of cell division while maintaining the undifferentiated state.
Potency - the capacity to differentiate into specialized cell types. In the strictest sense, this requires stem cells to be either totipotent or pluripotent - to be able to give rise to any mature cell type, although multipotent or unipotent progenitor cells are sometimes referred to as stem cells.
[edit] Potency definitions
Pluripotent, embryonic stem cells originate as inner mass cells within a blastocyst. The stem cells can become any tissue in the body, excluding a placenta. Only the morula's cells are totipotent, able to become all tissues and a placenta.Potency specifies the differentiation potential (the potential to differentiate into different cell types) of the stem cell.
Totipotent stem cells are produced from the fusion of an egg and sperm cell. Cells produced by the first few divisions of the fertilized egg are also totipotent. These cells can differentiate into embryonic and extraembryonic cell types.
Pluripotent stem cells are the descendants of totipotent cells and can differentiate into cells derived from any of the three germ layers.
Multipotent stem cells can produce only cells of a closely related family of cells (e.g. hematopoietic stem cells differentiate into red blood cells, white blood cells, platelets, etc.).
Unipotent cells can produce only one cell type, but have the property of self-renewal which distinguishes them from non-stem cells (e.g. muscle stem cells).
[edit] Identifying stem cells
The practical definition of a stem cell is the functional definition - the ability to regenerate tissue over a lifetime. For example, the gold standard test for a bone marrow or hematopoietic stem cell (HSC) is the ability to transplant one cell and save an individual without HSCs. In this case, a stem cell must be able to produce new blood cells and immune cells over a long term, demonstrating potency. It should also be possible to isolate stem cells from the transplanted individual, which can themselves be transplanted into another individual without HSCs, demonstrating that the stem cell was able to self-renew.
Properties of stem cells can be illustrated in vitro, using methods such as clonogenic assays, where single cells are characterized by their ability to differentiate and self-renew.[4][5] As well, stem cells can be isolated based on a distinctive set of cell surface markers. However, in vitro culture conditions can alter the behavior of cells, making it unclear whether the cells will behave in a similar manner in vivo. Considerable debate exists whether some proposed adult cell populations are truly stem cells.
[edit] Embryonic stem cells
Main article: Embryonic stem cell
Embryonic stem cell lines (ES cell lines) are cultures of cells derived from the epiblast tissue of the inner cell mass (ICM) of a blastocyst or earlier morula stage embryos.[6] A blastocyst is an early stage embryo—approximately four to five days old in humans and consisting of 50–150 cells. ES cells are pluripotent and give rise during development to all derivatives of the three primary germ layers: ectoderm, endoderm and mesoderm. In other words, they can develop into each of the more than 200 cell types of the adult body when given sufficient and necessary stimulation for a specific cell type. They do not contribute to the extra-embryonic membranes or the placenta.
Nearly all research to date has taken place using mouse embryonic stem cells (mES) or human embryonic stem cells (hES). Both have the essential stem cell characteristics, yet they require very different environments in order to maintain an undifferentiated state. Mouse ES cells are grown on a layer of gelatin and require the presence of Leukemia Inhibitory Factor (LIF).[7] Human ES cells are grown on a feeder layer of mouse embryonic fibroblasts (MEFs) and require the presence of basic Fibroblast Growth Factor (bFGF or FGF-2).[8] Without optimal culture conditions or genetic manipulation,[9] embryonic stem cells will rapidly differentiate.
A human embryonic stem cell is also defined by the presence of several transcription factors and cell surface proteins. The transcription factors Oct-4, Nanog, and SOX2 form the core regulatory network that ensures the suppression of genes that lead to differentiation and the maintenance of pluripotency.[10] The cell surface antigens most commonly used to identify hES cells are the glycolipids SSEA3 and SSEA4 and the keratan sulfate antigens Tra-1-60 and Tra-1-81. The molecular definition of a stem cell includes many more proteins and continues to be a topic of research.[11]
After nearly ten years of research[12], there are no approved treatments or human trials using embryonic stem cells. ES cells, being totipotent cells, require specific signals for correct differentiation - if injected directly into another body, ES cells will differentiate into many different types of cells, causing a teratoma. Differentiating ES cells into usable cells while avoiding transplant rejection are just a few of the hurdles that embryonic stem cell researchers still face.[13] Many nations currently have moratoria on either ES cell research or the production of new ES cell lines. Because of their combined abilities of unlimited expansion and pluripotency, embryonic stem cells remain a theoretically potential source for regenerative medicine and tissue replacement after injury or disease.
[edit] Adult stem cells
Main article: Adult stem cell
Stem cell division and differentiation. A - stem cell; B - progenitor cell; C - differentiated cell; 1 - symmetric stem cell division; 2 - asymmetric stem cell division; 3 - progenitor division; 4 - terminal differentiationThe term adult stem cell refers to any cell which is found in a developed organism that has two properties: the ability to divide and create another cell like itself and also divide and create a cell more differentiated than itself. Also known as somatic (from Greek Σωματικóς, "of the body") stem cells and germline (giving rise to gametes) stem cells, they can be found in children, as well as adults.[14]
Pluripotent adult stem cells are rare and generally small in number but can be found in a number of tissues including umbilical cord blood.[15] A great deal of adult stem cell research has focused on clarifying their capacity to divide or self-renew indefinitely and their differentiation potential.[16] In mice, pluripotent stem cells are directly generated from adult fibroblast cultures.[17]
Most adult stem cells are lineage-restricted (multipotent) and are generally referred to by their tissue origin (mesenchymal stem cell, adipose-derived stem cell, endothelial stem cell, etc.).[18][19]
Adult stem cell treatments have been successfully used for many years to treat leukemia and related bone/blood cancers through bone marrow transplants.[20] Adult stem cells are also used in veterinary medicine to treat tendon and ligament injuries in horses.[21] The use of adult stem cells in research and therapy is not as controversial as embryonic stem cells, because the production of adult stem cells does not require the destruction of an embryo. Additionally, because in some instances adult stem cells can be obtained from the intended recipient, (an autograft) the risk of rejection is essentially non-existent in these situations. Consequently, more US government funding is being provided for adult stem cell research.[22]
[edit] Lineage
Main article: Stem cell line
To ensure self-renewal, stem cells undergo two types of cell division (see Stem cell division and differentiation diagram). Symmetric division gives rise to two identical daughter cells both endowed with stem cell properties. Asymmetric division, on the other hand, produces only one stem cell and a progenitor cell with limited self-renewal potential. Progenitors can go through several rounds of cell division before terminally differentiating into a mature cell. It is possible that the molecular distinction between symmetric and asymmetric divisions lies in differential segregation of cell membrane proteins (such as receptors) between the daughter cells.[23]
An alternative theory is that stem cells remain undifferentiated due to environmental cues in their particular niche. Stem cells differentiate when they leave that niche or no longer receive those signals. Studies in Drosophila germarium have identified the signals dpp and adherins junctions that prevent germarium stem cells from differentiating.[24][25]
Main article: Induced Pluripotent Stem Cell
The signals that lead to reprogramming of cells to an embryonic-like state are also being investigated. These signal pathways include several transcription factors including the oncogene c-Myc. Initial studies indicate that transformation of mice cells with a combination of these anti-differentiation signals can reverse differentiation and may allow adult cells to become pluripotent.[26] However, the need to transform these cells with an oncogene may prevent the use of this approach in therapy.
[edit] Treatments
Main article: Stem cell treatments
Medical researchers believe that stem cell therapy has the potential to dramatically change the treatment of human disease. A number of adult stem cell therapies already exist, particularly bone marrow transplants that are used to treat leukemia.[27] In the future, medical researchers anticipate being able to use technologies derived from stem cell research to treat a wider variety of diseases including cancer, Parkinson's disease, spinal cord injuries,Amyotrophic lateral sclerosis and muscle damage, amongst a number of other impairments and conditions.[28][29] However, there still exists a great deal of social and scientific uncertainty surrounding stem cell research, which could possibly be overcome through public debate and future research, and further education of the public.
Stem cells, however, are already used extensively in research, and some scientists do not see cell therapy as the first goal of the research, but see the investigation of stem cells as a goal worthy in itself.[30]
[edit] Controversy surrounding human embryonic stem cell research
Main article: Stem cell controversy
There exists a widespread controversy over human embryonic stem cell research that emanates from the techniques used in the creation and usage of stem cells. Human embryonic stem cell research is controversial because, with the present state of technology, starting a stem cell line requires the destruction of a human embryo and/or therapeutic cloning. However, recently, it has been shown in principle that adult stem cell lines can be manipulated to generate embryonic-like stem cell lines using a single-cell biopsy similar to that used in preimplantation genetic diagnosis that may allow stem cell creation without embryonic destruction.[31] It is not the entire field of stem cell research, but the specific field of human embryonic stem cell research that is at the centre of an ethical debate.
Opponents of the research argue that embryonic stem cell technologies are a slippery slope to reproductive cloning and can fundamentally devalue human life. Those in the pro-life movement argue that a human embryo is a human life and is therefore entitled to protection.
Contrarily, supporters of embryonic stem cell research argue that such research should be pursued because the resultant treatments could have significant medical potential. It is also noted that excess embryos created for in vitro fertilization could be donated with consent and used for the research.
The ensuing debate has prompted authorities around the world to seek regulatory frameworks and highlighted the fact that stem cell research represents a social and ethical challenge.
[edit] Key stem cell research events
1960s - Joseph Altman and Gopal Das present scientific evidence of adult neurogenesis, ongoing stem cell activity in the brain; their reports contradict Cajal's "no new neurons" dogma and are largely ignored.
1963 - McCulloch and Till illustrate the presence of self-renewing cells in mouse bone marrow.
1968 - Bone marrow transplant between two siblings successfully treats SCID.
1978 - Haematopoietic stem cells are discovered in human cord blood.
1981 - Mouse embryonic stem cells are derived from the inner cell mass by scientists Martin Evans, Matthew Kaufman, and Gail R. Martin. Gail Martin is attributed for coining the term "Embryonic Stem Cell".
1992 - Neural stem cells are cultured in vitro as neurospheres.
1997 - Leukemia is shown to originate from a haematopoietic stem cell, the first direct evidence for cancer stem cells.
1998 - James Thomson and coworkers derive the first human embryonic stem cell line at the University of Wisconsin-Madison.
2000s - Several reports of adult stem cell plasticity are published.
2001 - Scientists at Advanced Cell Technology clone first early (four- to six-cell stage) human embryos for the purpose of generating embryonic stem cells.[32]
2003 - Dr. Songtao Shi of NIH discovers new source of adult stem cells in children's primary teeth.[33]
2004-2005 - Korean researcher Hwang Woo-Suk claims to have created several human embryonic stem cell lines from unfertilised human oocytes. The lines were later shown to be fabricated.
2005 - Researchers at Kingston University in England claim to have discovered a third category of stem cell, dubbed cord-blood-derived embryonic-like stem cells (CBEs), derived from umbilical cord blood. The group claims these cells are able to differentiate into more types of tissue than adult stem cells.
August 2006 - Rat Induced pluripotent stem cells: the journal Cell publishes Kazutoshi Takahashi and Shinya Yamanaka, "Induction of Pluripotent Stem Cells from Mouse Embryonic and Adult Fibroblast Cultures by Defined Factors".
October 2006 - Scientists in England create the first ever artificial liver cells using umbilical cord blood stem cells.[34][35]
January 2007 - Scientists at Wake Forest University led by Dr. Anthony Atala and Harvard University report discovery of a new type of stem cell in amniotic fluid.[5] This may potentially provide an alternative to embryonic stem cells for use in research and therapy.[36]
June 2007 - Research reported by three different groups shows that normal skin cells can be reprogrammed to an embryonic state in mice.[37] In the same month, scientist Shoukhrat Mitalipov reports the first successful creation of a primate stem cell line through somatic cell nuclear transfer[38]
October 2007 - Mario Capecchi, Martin Evans, and Oliver Smithies win the 2007 Nobel Prize for Physiology or Medicine for their work on embryonic stem cells from mice using gene targeting strategies producing genetically engineered mice (known as knockout mice) for gene research.[39]
November 2007 - Human Induced pluripotent stem cells: Two similar papers released by their respective journals prior to formal publication: in Cell by Kazutoshi Takahashi and Shinya Yamanaka, "Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by Defined Factors", and in Science by Junying Yu, et al., from the research group of James Thomson, "Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells": pluripotent stem cells generated from mature human fibroblasts. It is possible now to produce a stem cell from almost any other human cell instead of using embryos as needed previously, albeit the risk of tumorigenesis due to c-myc and retroviral gene transfer remains to be determined.
January 2008 - Human embryonic stem cell lines were generated without destruction of the embryo[40]
January 2008 - Development of human cloned blastocysts following somatic cell nuclear transfer with adult fibroblasts[41]
February 2008 - Generation of Pluripotent Stem Cells from Adult Mouse Liver and Stomach: these iPS cells seem to be more similar to embryonic stem cells than the previous developed iPS cells and not tumorigenic, moreover genes that are required for iPS cells do not need to be inserted into specific sites, which encourages the development of non-viral reprogramming techniques. [42][43]
[edit] Stem cell funding & policy debate in the US
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Please improve the article by adding information on neglected viewpoints, or discuss the issue on the talk page.
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1993 - As per the National Institutes of Health Revitalization Act, Congress and President Bill Clinton give the NIH direct authority to fund human embryo research for the first time.[44]
1995 - The U.S. Congress enacts into law an appropriations bill attached to which is the Dickey Amendment which prohibited federally appropriated funds to be used for research where human embryos would be either created or destroyed. This predates the creation of the first human embryonic stem cell lines.
1999 - After the creation of the first human embryonic stem cell lines in 1998 by James Thomson of the University of Wisconsin, Harriet Rabb, the top lawyer at the Department of Health and Human Services, releases a legal opinion that would set the course for Clinton Administration policy. Federal funds, obviously, could not be used to derive stem cell lines (because derivation involves embryo destruction). However, she concludes that because human embryonic stem cells "are not a human embryo within the statutory definition," the Dickey-Wicker Amendment does not apply to them. The NIH was therefore free to give federal funding to experiments involving the cells themselves. President Clinton strongly endorses the new guidelines, noting that human embryonic stem cell research promised "potentially staggering benefits." And with the guidelines in place, the NIH begins accepting grant proposals from scientists.[45]
02 November, 2004 - California voters approve Proposition 71, which provides $3 billion in state funds over ten years to human embryonic stem cell research.
2001-2006 - U.S. President George W. Bush signs an executive order which restricts federally-funded stem cell research on embryonic stem cells to the already derived cell lines. He supports federal funding for embryonic stem cell research on the already existing lines of approximately $100 million and $250 million for research on adult and animal stem cells.
5 May, 2006 - Senator Rick Santorum introduces bill number S. 2754, or the Alternative Pluripotent Stem Cell Therapies Enhancement Act, into the U.S. Senate.
18 July, 2006 - The U.S. Senate passes the Stem Cell Research Enhancement Act H.R. 810 and votes down Senator Santorum's S. 2754.
19 July, 2006 - President George W. Bush vetoes H.R. 810 (Stem Cell Research Enhancement Act), a bill that would have reversed the Gingrich-era appropriations amendment which made it illegal for federal money to be used for research where stem cells are derived from the destruction of an embryo.
07 November, 2006 - The people of the U.S. state of Missouri passed Amendment 2, which allows usage of any stem cell research and therapy allowed under federal law, but prohibits human reproductive cloning.[46]
16 February, 2007 – The California Institute for Regenerative Medicine became the biggest financial backer of human embryonic stem cell research in the United States when they awarded nearly $45 million in research grants.[47]
[edit] See also
The American Society for Cell Biology
California Institute for Regenerative Medicine
Genetics Policy Institute
Cancer stem cells
Induced Pluripotent Stem Cell (iPS Cell)
Odontis
[edit] References
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^ Siminovitch L, McCulloch EA, Till JE (1963). "The distribution of colony-forming cells among spleen colonies". Journal of Cellular and Comparative Physiology 62: 327–36. doi:10.1002/jcp.1030620313. PMID 14086156.
^ Tuch BE (2006). "Stem cells--a clinical update". Australian family physician 35 (9): 719–21. PMID 16969445.
^ Friedenstein AJ, Deriglasova UF, Kulagina NN, Panasuk AF, Rudakowa SF, Luria EA, Ruadkow IA (1974). "Precursors for fibroblasts in different populations of hematopoietic cells as detected by the in vitro colony assay method". Exp Hematol 2 (2): 83–92. PMID 4455512.
^ Friedenstein AJ, Gorskaja JF, Kulagina NN (1976). "Fibroblast precursors in normal and irradiated mouse hematopoietic organs". Exp Hematol 4 (5): 267–74. PMID 976387.
^ FOXNews.com - New Stem-Cell Procedure Doesn't Harm Embryos, Company Claims - Biology | Astronomy | Chemistry | Physics
^ [1] , Mouse Embryonic Stem (ES) Cell Culture-Current Protocols in Molecular Biology
^ [2], Culture of Human Embryonic Stem Cells (hESC) NIH
^ Chambers I, Colby D, Robertson M, et al (2003). "Functional expression cloning of Nanog, a pluripotency sustaining factor in embryonic stem cells". Cell 113 (5): 643–55. doi:10.1016/S0092-8674(03)00392-1. PMID 12787505.
^ Boyer LA, Lee TI, Cole MF, et al (2005). "Core transcriptional regulatory circuitry in human embryonic stem cells". Cell 122 (6): 947–56. doi:10.1016/j.cell.2005.08.020. PMID 16153702.
^ Adewumi O, Aflatoonian B, Ahrlund-Richter L, et al (2007). "Characterization of human embryonic stem cell lines by the International Stem Cell Initiative". Nat. Biotechnol. 25 (7): 803–16. doi:10.1038/nbt1318. PMID 17572666.
^ Thomson J, Itskovitz-Eldor J, Shapiro S, Waknitz M, Swiergiel J, Marshall V, Jones J (1998). "Embryonic stem cell lines derived from human blastocysts.". Science 282 (5391): 1145–7. doi:10.1126/science.282.5391.1145. PMID 9804556.
^ Wu DC, Boyd AS, Wood KJ (2007). "Embryonic stem cell transplantation: potential applicability in cell replacement therapy and regenerative medicine". Front. Biosci. 12: 4525–35. doi:10.2741/2407. PMID 17485394.
^ Jiang Y, Jahagirdar BN, Reinhardt RL, et al (2002). "Pluripotency of mesenchymal stem cells derived from adult marrow". Nature 418 (6893): 41–9. doi:10.1038/nature00870. PMID 12077603.
^ Ratajczak MZ, Machalinski B, Wojakowski W, Ratajczak J, Kucia M (2007). "A hypothesis for an embryonic origin of pluripotent Oct-4(+) stem cells in adult bone marrow and other tissues". Leukemia 21 (5): 860–7. doi:10.1038/sj.leu.2404630. PMID 17344915.
^ Gardner RL (2002). "Stem cells: potency, plasticity and public perception". Journal of Anatomy 200 (3): 277–82. doi:10.1046/j.1469-7580.2002.00029.x. PMID 12033732.
^ Takahashi K, Yamanaka S (2006). "Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors". Cell 126 (4): 663–76. doi:10.1016/j.cell.2006.07.024. PMID 16904174.
^ Barrilleaux B, Phinney DG, Prockop DJ, O'Connor KC (2006). "Review: ex vivo engineering of living tissues with adult stem cells". Tissue Eng. 12 (11): 3007–19. doi:10.1089/ten.2006.12.3007. PMID 17518617.
^ Gimble JM, Katz AJ, Bunnell BA (2007). "Adipose-derived stem cells for regenerative medicine". Circ. Res. 100 (9): 1249–60. doi:10.1161/01.RES.0000265074.83288.09. PMID 17495232.
^ [3], Bone Marrow Transplant
^ Kane, Ed (2008-05-01). "Stem-cell therapy shows promise for horse soft-tissue injury, disease", DVM Newsmagazine. Retrieved on 2008-06-12.
^ [4],USDHHS Stem Cell FAQ 2004
^ Beckmann J, Scheitza S, Wernet P, Fischer JC, Giebel B (2007). "Asymmetric cell division within the human hematopoietic stem and progenitor cell compartment: identification of asymmetrically segregating proteins". Blood 109 (12): 5494–501. doi:10.1182/blood-2006-11-055921. PMID 17332245.
^ Xie T, Spradling A (1998). "decapentaplegic is essential for the maintenance and division of germline stem cells in the Drosophila ovary". Cell 94 (2): 251–60. doi:10.1016/S0092-8674(00)81424-5. PMID 9695953.
^ Song X, Zhu C, Doan C, Xie T (2002). "Germline stem cells anchored by adherens junctions in the Drosophila ovary niches.". Science 296 (5574): 1855–7. doi:10.1126/science.1069871. PMID 12052957.
^ Takahashi K, Yamanaka S (2006). "Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors". Cell 126 (4): 663–76. doi:10.1016/j.cell.2006.07.024. PMID 16904174.
^ Gahrton G, Björkstrand B (2000). "Progress in haematopoietic stem cell transplantation for multiple myeloma". J Intern Med 248 (3): 185–201. doi:10.1046/j.1365-2796.2000.00706.x. PMID 10971785.
^ Lindvall O (2003). "Stem cells for cell therapy in Parkinson's disease". Pharmacol Res 47 (4): 279–87. doi:10.1016/S1043-6618(03)00037-9. PMID 12644384.
^ Goldman S, Windrem M (2006). "Cell replacement therapy in neurological disease". Philos Trans R Soc Lond B Biol Sci 361 (1473): 1463–75. doi:10.1098/rstb.2006.1886. PMID 16939969.
^ Wade N (2006-08-14). "Some Scientists See Shift in Stem Cell Hopes". New York Times. Retrieved on 2006-12-28.
^ Firm Creates Stem Cells Without Hurting Embryos : NPR
^ The First Human Cloned Embryo: Scientific American
^ Shostak S (2006). "(Re)defining stem cells". Bioessays 28 (3): 301–8. doi:10.1002/bies.20376. PMID 16479584.
^ Good News for Alcoholics | Biotechnology | DISCOVER Magazine
^ Scotsman.com News
^ Amniotic fluid yields stem cells, Harvard researchers report - Boston.com
^ Cyranoski D (2007). "Simple switch turns cells embryonic". Nature 447 (7145): 618–9. doi:10.1038/447618a. PMID 17554270.
^ Mitalipov SM, Zhou Q, Byrne JA, Ji WZ, Norgren RB, Wolf DP (2007). "Reprogramming following somatic cell nuclear transfer in primates is dependent upon nuclear remodeling". Hum Reprod 22 (8): 2232–42. doi:10.1093/humrep/dem136. PMID 17562675.
^ "The Nobel Prize in Physiology or Medicine 2007". Nobelprize.org. Retrieved on 8 October 2007.
^ Cell Stem Cell - Chung et al
^ http://stemcells.alphamedpress.org/cgi/reprint/2007-0252v1.pdf
^ Generation of Pluripotent Stem Cells from Adult Mo...[Science. 2008] - PubMed Result
^ The Niche: Adult cell types besides skin are reprogrammed
^ Dispatches: The Politics of Stem Cells PBS
^ Dispatches: The Politics of Stem Cells PBS
^ Full-text of Missouri Constitution Amendment 2
^ Calif. Awards $45M in Stem Cell Grants Associated Press, Feb. 17, 2007.
[edit] External links
General
Tell Me About Stem Cells: Quick and simple guide explaining the science behind stem cells
Stem Cell Basics
Nature Reports Stem Cells: Introductory material, research advances and debates concerning stem cell research.
Understanding Stem Cells: A View of the Science and Issues from the National Academies
Scientific American Magazine (June 2004 Issue) The Stem Cell Challenge
Scientific American Magazine (July 2006 Issue) Stem Cells: The Real Culprits in Cancer?
National Institutes of Health
Stem Cell Research Forum of India
Ethics of Stem Cell Research entry at the Stanford Encyclopedia of Philosophy by Andrew Siegel
Peer-reviewed journals
STEM CELLS®
Cytotherapy
Cloning and Stem Cells
Stem Cells and Development
Regenerative Medicine
Isolation of amniotic stem cell lines with potential for therapy
As stem cells can be grown and transformed into specialized cells with characteristics consistent with cells of various tissues such as muscles or nerves through cell culture, their use in medical therapies has been proposed. In particular, embryonic cell lines, autologous embryonic stem cells generated through therapeutic cloning, and highly plastic adult stem cells from the umbilical cord blood or bone marrow are touted as promising candidates.[3]
Contents [hide]
1 Properties of stem cells
1.1 Potency definitions
1.2 Identifying stem cells
2 Embryonic stem cells
3 Adult stem cells
4 Lineage
5 Treatments
6 Controversy surrounding human embryonic stem cell research
7 Key stem cell research events
8 Stem cell funding & policy debate in the US
9 See also
10 References
11 External links
[edit] Properties of stem cells
The classical definition of a stem cell requires that it possess two properties:
Self-renewal - the ability to go through numerous cycles of cell division while maintaining the undifferentiated state.
Potency - the capacity to differentiate into specialized cell types. In the strictest sense, this requires stem cells to be either totipotent or pluripotent - to be able to give rise to any mature cell type, although multipotent or unipotent progenitor cells are sometimes referred to as stem cells.
[edit] Potency definitions
Pluripotent, embryonic stem cells originate as inner mass cells within a blastocyst. The stem cells can become any tissue in the body, excluding a placenta. Only the morula's cells are totipotent, able to become all tissues and a placenta.Potency specifies the differentiation potential (the potential to differentiate into different cell types) of the stem cell.
Totipotent stem cells are produced from the fusion of an egg and sperm cell. Cells produced by the first few divisions of the fertilized egg are also totipotent. These cells can differentiate into embryonic and extraembryonic cell types.
Pluripotent stem cells are the descendants of totipotent cells and can differentiate into cells derived from any of the three germ layers.
Multipotent stem cells can produce only cells of a closely related family of cells (e.g. hematopoietic stem cells differentiate into red blood cells, white blood cells, platelets, etc.).
Unipotent cells can produce only one cell type, but have the property of self-renewal which distinguishes them from non-stem cells (e.g. muscle stem cells).
[edit] Identifying stem cells
The practical definition of a stem cell is the functional definition - the ability to regenerate tissue over a lifetime. For example, the gold standard test for a bone marrow or hematopoietic stem cell (HSC) is the ability to transplant one cell and save an individual without HSCs. In this case, a stem cell must be able to produce new blood cells and immune cells over a long term, demonstrating potency. It should also be possible to isolate stem cells from the transplanted individual, which can themselves be transplanted into another individual without HSCs, demonstrating that the stem cell was able to self-renew.
Properties of stem cells can be illustrated in vitro, using methods such as clonogenic assays, where single cells are characterized by their ability to differentiate and self-renew.[4][5] As well, stem cells can be isolated based on a distinctive set of cell surface markers. However, in vitro culture conditions can alter the behavior of cells, making it unclear whether the cells will behave in a similar manner in vivo. Considerable debate exists whether some proposed adult cell populations are truly stem cells.
[edit] Embryonic stem cells
Main article: Embryonic stem cell
Embryonic stem cell lines (ES cell lines) are cultures of cells derived from the epiblast tissue of the inner cell mass (ICM) of a blastocyst or earlier morula stage embryos.[6] A blastocyst is an early stage embryo—approximately four to five days old in humans and consisting of 50–150 cells. ES cells are pluripotent and give rise during development to all derivatives of the three primary germ layers: ectoderm, endoderm and mesoderm. In other words, they can develop into each of the more than 200 cell types of the adult body when given sufficient and necessary stimulation for a specific cell type. They do not contribute to the extra-embryonic membranes or the placenta.
Nearly all research to date has taken place using mouse embryonic stem cells (mES) or human embryonic stem cells (hES). Both have the essential stem cell characteristics, yet they require very different environments in order to maintain an undifferentiated state. Mouse ES cells are grown on a layer of gelatin and require the presence of Leukemia Inhibitory Factor (LIF).[7] Human ES cells are grown on a feeder layer of mouse embryonic fibroblasts (MEFs) and require the presence of basic Fibroblast Growth Factor (bFGF or FGF-2).[8] Without optimal culture conditions or genetic manipulation,[9] embryonic stem cells will rapidly differentiate.
A human embryonic stem cell is also defined by the presence of several transcription factors and cell surface proteins. The transcription factors Oct-4, Nanog, and SOX2 form the core regulatory network that ensures the suppression of genes that lead to differentiation and the maintenance of pluripotency.[10] The cell surface antigens most commonly used to identify hES cells are the glycolipids SSEA3 and SSEA4 and the keratan sulfate antigens Tra-1-60 and Tra-1-81. The molecular definition of a stem cell includes many more proteins and continues to be a topic of research.[11]
After nearly ten years of research[12], there are no approved treatments or human trials using embryonic stem cells. ES cells, being totipotent cells, require specific signals for correct differentiation - if injected directly into another body, ES cells will differentiate into many different types of cells, causing a teratoma. Differentiating ES cells into usable cells while avoiding transplant rejection are just a few of the hurdles that embryonic stem cell researchers still face.[13] Many nations currently have moratoria on either ES cell research or the production of new ES cell lines. Because of their combined abilities of unlimited expansion and pluripotency, embryonic stem cells remain a theoretically potential source for regenerative medicine and tissue replacement after injury or disease.
[edit] Adult stem cells
Main article: Adult stem cell
Stem cell division and differentiation. A - stem cell; B - progenitor cell; C - differentiated cell; 1 - symmetric stem cell division; 2 - asymmetric stem cell division; 3 - progenitor division; 4 - terminal differentiationThe term adult stem cell refers to any cell which is found in a developed organism that has two properties: the ability to divide and create another cell like itself and also divide and create a cell more differentiated than itself. Also known as somatic (from Greek Σωματικóς, "of the body") stem cells and germline (giving rise to gametes) stem cells, they can be found in children, as well as adults.[14]
Pluripotent adult stem cells are rare and generally small in number but can be found in a number of tissues including umbilical cord blood.[15] A great deal of adult stem cell research has focused on clarifying their capacity to divide or self-renew indefinitely and their differentiation potential.[16] In mice, pluripotent stem cells are directly generated from adult fibroblast cultures.[17]
Most adult stem cells are lineage-restricted (multipotent) and are generally referred to by their tissue origin (mesenchymal stem cell, adipose-derived stem cell, endothelial stem cell, etc.).[18][19]
Adult stem cell treatments have been successfully used for many years to treat leukemia and related bone/blood cancers through bone marrow transplants.[20] Adult stem cells are also used in veterinary medicine to treat tendon and ligament injuries in horses.[21] The use of adult stem cells in research and therapy is not as controversial as embryonic stem cells, because the production of adult stem cells does not require the destruction of an embryo. Additionally, because in some instances adult stem cells can be obtained from the intended recipient, (an autograft) the risk of rejection is essentially non-existent in these situations. Consequently, more US government funding is being provided for adult stem cell research.[22]
[edit] Lineage
Main article: Stem cell line
To ensure self-renewal, stem cells undergo two types of cell division (see Stem cell division and differentiation diagram). Symmetric division gives rise to two identical daughter cells both endowed with stem cell properties. Asymmetric division, on the other hand, produces only one stem cell and a progenitor cell with limited self-renewal potential. Progenitors can go through several rounds of cell division before terminally differentiating into a mature cell. It is possible that the molecular distinction between symmetric and asymmetric divisions lies in differential segregation of cell membrane proteins (such as receptors) between the daughter cells.[23]
An alternative theory is that stem cells remain undifferentiated due to environmental cues in their particular niche. Stem cells differentiate when they leave that niche or no longer receive those signals. Studies in Drosophila germarium have identified the signals dpp and adherins junctions that prevent germarium stem cells from differentiating.[24][25]
Main article: Induced Pluripotent Stem Cell
The signals that lead to reprogramming of cells to an embryonic-like state are also being investigated. These signal pathways include several transcription factors including the oncogene c-Myc. Initial studies indicate that transformation of mice cells with a combination of these anti-differentiation signals can reverse differentiation and may allow adult cells to become pluripotent.[26] However, the need to transform these cells with an oncogene may prevent the use of this approach in therapy.
[edit] Treatments
Main article: Stem cell treatments
Medical researchers believe that stem cell therapy has the potential to dramatically change the treatment of human disease. A number of adult stem cell therapies already exist, particularly bone marrow transplants that are used to treat leukemia.[27] In the future, medical researchers anticipate being able to use technologies derived from stem cell research to treat a wider variety of diseases including cancer, Parkinson's disease, spinal cord injuries,Amyotrophic lateral sclerosis and muscle damage, amongst a number of other impairments and conditions.[28][29] However, there still exists a great deal of social and scientific uncertainty surrounding stem cell research, which could possibly be overcome through public debate and future research, and further education of the public.
Stem cells, however, are already used extensively in research, and some scientists do not see cell therapy as the first goal of the research, but see the investigation of stem cells as a goal worthy in itself.[30]
[edit] Controversy surrounding human embryonic stem cell research
Main article: Stem cell controversy
There exists a widespread controversy over human embryonic stem cell research that emanates from the techniques used in the creation and usage of stem cells. Human embryonic stem cell research is controversial because, with the present state of technology, starting a stem cell line requires the destruction of a human embryo and/or therapeutic cloning. However, recently, it has been shown in principle that adult stem cell lines can be manipulated to generate embryonic-like stem cell lines using a single-cell biopsy similar to that used in preimplantation genetic diagnosis that may allow stem cell creation without embryonic destruction.[31] It is not the entire field of stem cell research, but the specific field of human embryonic stem cell research that is at the centre of an ethical debate.
Opponents of the research argue that embryonic stem cell technologies are a slippery slope to reproductive cloning and can fundamentally devalue human life. Those in the pro-life movement argue that a human embryo is a human life and is therefore entitled to protection.
Contrarily, supporters of embryonic stem cell research argue that such research should be pursued because the resultant treatments could have significant medical potential. It is also noted that excess embryos created for in vitro fertilization could be donated with consent and used for the research.
The ensuing debate has prompted authorities around the world to seek regulatory frameworks and highlighted the fact that stem cell research represents a social and ethical challenge.
[edit] Key stem cell research events
1960s - Joseph Altman and Gopal Das present scientific evidence of adult neurogenesis, ongoing stem cell activity in the brain; their reports contradict Cajal's "no new neurons" dogma and are largely ignored.
1963 - McCulloch and Till illustrate the presence of self-renewing cells in mouse bone marrow.
1968 - Bone marrow transplant between two siblings successfully treats SCID.
1978 - Haematopoietic stem cells are discovered in human cord blood.
1981 - Mouse embryonic stem cells are derived from the inner cell mass by scientists Martin Evans, Matthew Kaufman, and Gail R. Martin. Gail Martin is attributed for coining the term "Embryonic Stem Cell".
1992 - Neural stem cells are cultured in vitro as neurospheres.
1997 - Leukemia is shown to originate from a haematopoietic stem cell, the first direct evidence for cancer stem cells.
1998 - James Thomson and coworkers derive the first human embryonic stem cell line at the University of Wisconsin-Madison.
2000s - Several reports of adult stem cell plasticity are published.
2001 - Scientists at Advanced Cell Technology clone first early (four- to six-cell stage) human embryos for the purpose of generating embryonic stem cells.[32]
2003 - Dr. Songtao Shi of NIH discovers new source of adult stem cells in children's primary teeth.[33]
2004-2005 - Korean researcher Hwang Woo-Suk claims to have created several human embryonic stem cell lines from unfertilised human oocytes. The lines were later shown to be fabricated.
2005 - Researchers at Kingston University in England claim to have discovered a third category of stem cell, dubbed cord-blood-derived embryonic-like stem cells (CBEs), derived from umbilical cord blood. The group claims these cells are able to differentiate into more types of tissue than adult stem cells.
August 2006 - Rat Induced pluripotent stem cells: the journal Cell publishes Kazutoshi Takahashi and Shinya Yamanaka, "Induction of Pluripotent Stem Cells from Mouse Embryonic and Adult Fibroblast Cultures by Defined Factors".
October 2006 - Scientists in England create the first ever artificial liver cells using umbilical cord blood stem cells.[34][35]
January 2007 - Scientists at Wake Forest University led by Dr. Anthony Atala and Harvard University report discovery of a new type of stem cell in amniotic fluid.[5] This may potentially provide an alternative to embryonic stem cells for use in research and therapy.[36]
June 2007 - Research reported by three different groups shows that normal skin cells can be reprogrammed to an embryonic state in mice.[37] In the same month, scientist Shoukhrat Mitalipov reports the first successful creation of a primate stem cell line through somatic cell nuclear transfer[38]
October 2007 - Mario Capecchi, Martin Evans, and Oliver Smithies win the 2007 Nobel Prize for Physiology or Medicine for their work on embryonic stem cells from mice using gene targeting strategies producing genetically engineered mice (known as knockout mice) for gene research.[39]
November 2007 - Human Induced pluripotent stem cells: Two similar papers released by their respective journals prior to formal publication: in Cell by Kazutoshi Takahashi and Shinya Yamanaka, "Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by Defined Factors", and in Science by Junying Yu, et al., from the research group of James Thomson, "Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells": pluripotent stem cells generated from mature human fibroblasts. It is possible now to produce a stem cell from almost any other human cell instead of using embryos as needed previously, albeit the risk of tumorigenesis due to c-myc and retroviral gene transfer remains to be determined.
January 2008 - Human embryonic stem cell lines were generated without destruction of the embryo[40]
January 2008 - Development of human cloned blastocysts following somatic cell nuclear transfer with adult fibroblasts[41]
February 2008 - Generation of Pluripotent Stem Cells from Adult Mouse Liver and Stomach: these iPS cells seem to be more similar to embryonic stem cells than the previous developed iPS cells and not tumorigenic, moreover genes that are required for iPS cells do not need to be inserted into specific sites, which encourages the development of non-viral reprogramming techniques. [42][43]
[edit] Stem cell funding & policy debate in the US
This article or section may be inaccurate or unbalanced in favor of certain viewpoints.
Please improve the article by adding information on neglected viewpoints, or discuss the issue on the talk page.
The examples and perspective in this article or section may not represent a worldwide view of the subject.
Please improve this article or discuss the issue on the talk page.
1993 - As per the National Institutes of Health Revitalization Act, Congress and President Bill Clinton give the NIH direct authority to fund human embryo research for the first time.[44]
1995 - The U.S. Congress enacts into law an appropriations bill attached to which is the Dickey Amendment which prohibited federally appropriated funds to be used for research where human embryos would be either created or destroyed. This predates the creation of the first human embryonic stem cell lines.
1999 - After the creation of the first human embryonic stem cell lines in 1998 by James Thomson of the University of Wisconsin, Harriet Rabb, the top lawyer at the Department of Health and Human Services, releases a legal opinion that would set the course for Clinton Administration policy. Federal funds, obviously, could not be used to derive stem cell lines (because derivation involves embryo destruction). However, she concludes that because human embryonic stem cells "are not a human embryo within the statutory definition," the Dickey-Wicker Amendment does not apply to them. The NIH was therefore free to give federal funding to experiments involving the cells themselves. President Clinton strongly endorses the new guidelines, noting that human embryonic stem cell research promised "potentially staggering benefits." And with the guidelines in place, the NIH begins accepting grant proposals from scientists.[45]
02 November, 2004 - California voters approve Proposition 71, which provides $3 billion in state funds over ten years to human embryonic stem cell research.
2001-2006 - U.S. President George W. Bush signs an executive order which restricts federally-funded stem cell research on embryonic stem cells to the already derived cell lines. He supports federal funding for embryonic stem cell research on the already existing lines of approximately $100 million and $250 million for research on adult and animal stem cells.
5 May, 2006 - Senator Rick Santorum introduces bill number S. 2754, or the Alternative Pluripotent Stem Cell Therapies Enhancement Act, into the U.S. Senate.
18 July, 2006 - The U.S. Senate passes the Stem Cell Research Enhancement Act H.R. 810 and votes down Senator Santorum's S. 2754.
19 July, 2006 - President George W. Bush vetoes H.R. 810 (Stem Cell Research Enhancement Act), a bill that would have reversed the Gingrich-era appropriations amendment which made it illegal for federal money to be used for research where stem cells are derived from the destruction of an embryo.
07 November, 2006 - The people of the U.S. state of Missouri passed Amendment 2, which allows usage of any stem cell research and therapy allowed under federal law, but prohibits human reproductive cloning.[46]
16 February, 2007 – The California Institute for Regenerative Medicine became the biggest financial backer of human embryonic stem cell research in the United States when they awarded nearly $45 million in research grants.[47]
[edit] See also
The American Society for Cell Biology
California Institute for Regenerative Medicine
Genetics Policy Institute
Cancer stem cells
Induced Pluripotent Stem Cell (iPS Cell)
Odontis
[edit] References
^ Becker AJ, McCulloch EA, Till JE (1963). "Cytological demonstration of the clonal nature of spleen colonies derived from transplanted mouse marrow cells". Nature 197: 452–4. doi:10.1038/197452a0. PMID 13970094.
^ Siminovitch L, McCulloch EA, Till JE (1963). "The distribution of colony-forming cells among spleen colonies". Journal of Cellular and Comparative Physiology 62: 327–36. doi:10.1002/jcp.1030620313. PMID 14086156.
^ Tuch BE (2006). "Stem cells--a clinical update". Australian family physician 35 (9): 719–21. PMID 16969445.
^ Friedenstein AJ, Deriglasova UF, Kulagina NN, Panasuk AF, Rudakowa SF, Luria EA, Ruadkow IA (1974). "Precursors for fibroblasts in different populations of hematopoietic cells as detected by the in vitro colony assay method". Exp Hematol 2 (2): 83–92. PMID 4455512.
^ Friedenstein AJ, Gorskaja JF, Kulagina NN (1976). "Fibroblast precursors in normal and irradiated mouse hematopoietic organs". Exp Hematol 4 (5): 267–74. PMID 976387.
^ FOXNews.com - New Stem-Cell Procedure Doesn't Harm Embryos, Company Claims - Biology | Astronomy | Chemistry | Physics
^ [1] , Mouse Embryonic Stem (ES) Cell Culture-Current Protocols in Molecular Biology
^ [2], Culture of Human Embryonic Stem Cells (hESC) NIH
^ Chambers I, Colby D, Robertson M, et al (2003). "Functional expression cloning of Nanog, a pluripotency sustaining factor in embryonic stem cells". Cell 113 (5): 643–55. doi:10.1016/S0092-8674(03)00392-1. PMID 12787505.
^ Boyer LA, Lee TI, Cole MF, et al (2005). "Core transcriptional regulatory circuitry in human embryonic stem cells". Cell 122 (6): 947–56. doi:10.1016/j.cell.2005.08.020. PMID 16153702.
^ Adewumi O, Aflatoonian B, Ahrlund-Richter L, et al (2007). "Characterization of human embryonic stem cell lines by the International Stem Cell Initiative". Nat. Biotechnol. 25 (7): 803–16. doi:10.1038/nbt1318. PMID 17572666.
^ Thomson J, Itskovitz-Eldor J, Shapiro S, Waknitz M, Swiergiel J, Marshall V, Jones J (1998). "Embryonic stem cell lines derived from human blastocysts.". Science 282 (5391): 1145–7. doi:10.1126/science.282.5391.1145. PMID 9804556.
^ Wu DC, Boyd AS, Wood KJ (2007). "Embryonic stem cell transplantation: potential applicability in cell replacement therapy and regenerative medicine". Front. Biosci. 12: 4525–35. doi:10.2741/2407. PMID 17485394.
^ Jiang Y, Jahagirdar BN, Reinhardt RL, et al (2002). "Pluripotency of mesenchymal stem cells derived from adult marrow". Nature 418 (6893): 41–9. doi:10.1038/nature00870. PMID 12077603.
^ Ratajczak MZ, Machalinski B, Wojakowski W, Ratajczak J, Kucia M (2007). "A hypothesis for an embryonic origin of pluripotent Oct-4(+) stem cells in adult bone marrow and other tissues". Leukemia 21 (5): 860–7. doi:10.1038/sj.leu.2404630. PMID 17344915.
^ Gardner RL (2002). "Stem cells: potency, plasticity and public perception". Journal of Anatomy 200 (3): 277–82. doi:10.1046/j.1469-7580.2002.00029.x. PMID 12033732.
^ Takahashi K, Yamanaka S (2006). "Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors". Cell 126 (4): 663–76. doi:10.1016/j.cell.2006.07.024. PMID 16904174.
^ Barrilleaux B, Phinney DG, Prockop DJ, O'Connor KC (2006). "Review: ex vivo engineering of living tissues with adult stem cells". Tissue Eng. 12 (11): 3007–19. doi:10.1089/ten.2006.12.3007. PMID 17518617.
^ Gimble JM, Katz AJ, Bunnell BA (2007). "Adipose-derived stem cells for regenerative medicine". Circ. Res. 100 (9): 1249–60. doi:10.1161/01.RES.0000265074.83288.09. PMID 17495232.
^ [3], Bone Marrow Transplant
^ Kane, Ed (2008-05-01). "Stem-cell therapy shows promise for horse soft-tissue injury, disease", DVM Newsmagazine. Retrieved on 2008-06-12.
^ [4],USDHHS Stem Cell FAQ 2004
^ Beckmann J, Scheitza S, Wernet P, Fischer JC, Giebel B (2007). "Asymmetric cell division within the human hematopoietic stem and progenitor cell compartment: identification of asymmetrically segregating proteins". Blood 109 (12): 5494–501. doi:10.1182/blood-2006-11-055921. PMID 17332245.
^ Xie T, Spradling A (1998). "decapentaplegic is essential for the maintenance and division of germline stem cells in the Drosophila ovary". Cell 94 (2): 251–60. doi:10.1016/S0092-8674(00)81424-5. PMID 9695953.
^ Song X, Zhu C, Doan C, Xie T (2002). "Germline stem cells anchored by adherens junctions in the Drosophila ovary niches.". Science 296 (5574): 1855–7. doi:10.1126/science.1069871. PMID 12052957.
^ Takahashi K, Yamanaka S (2006). "Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors". Cell 126 (4): 663–76. doi:10.1016/j.cell.2006.07.024. PMID 16904174.
^ Gahrton G, Björkstrand B (2000). "Progress in haematopoietic stem cell transplantation for multiple myeloma". J Intern Med 248 (3): 185–201. doi:10.1046/j.1365-2796.2000.00706.x. PMID 10971785.
^ Lindvall O (2003). "Stem cells for cell therapy in Parkinson's disease". Pharmacol Res 47 (4): 279–87. doi:10.1016/S1043-6618(03)00037-9. PMID 12644384.
^ Goldman S, Windrem M (2006). "Cell replacement therapy in neurological disease". Philos Trans R Soc Lond B Biol Sci 361 (1473): 1463–75. doi:10.1098/rstb.2006.1886. PMID 16939969.
^ Wade N (2006-08-14). "Some Scientists See Shift in Stem Cell Hopes". New York Times. Retrieved on 2006-12-28.
^ Firm Creates Stem Cells Without Hurting Embryos : NPR
^ The First Human Cloned Embryo: Scientific American
^ Shostak S (2006). "(Re)defining stem cells". Bioessays 28 (3): 301–8. doi:10.1002/bies.20376. PMID 16479584.
^ Good News for Alcoholics | Biotechnology | DISCOVER Magazine
^ Scotsman.com News
^ Amniotic fluid yields stem cells, Harvard researchers report - Boston.com
^ Cyranoski D (2007). "Simple switch turns cells embryonic". Nature 447 (7145): 618–9. doi:10.1038/447618a. PMID 17554270.
^ Mitalipov SM, Zhou Q, Byrne JA, Ji WZ, Norgren RB, Wolf DP (2007). "Reprogramming following somatic cell nuclear transfer in primates is dependent upon nuclear remodeling". Hum Reprod 22 (8): 2232–42. doi:10.1093/humrep/dem136. PMID 17562675.
^ "The Nobel Prize in Physiology or Medicine 2007". Nobelprize.org. Retrieved on 8 October 2007.
^ Cell Stem Cell - Chung et al
^ http://stemcells.alphamedpress.org/cgi/reprint/2007-0252v1.pdf
^ Generation of Pluripotent Stem Cells from Adult Mo...[Science. 2008] - PubMed Result
^ The Niche: Adult cell types besides skin are reprogrammed
^ Dispatches: The Politics of Stem Cells PBS
^ Dispatches: The Politics of Stem Cells PBS
^ Full-text of Missouri Constitution Amendment 2
^ Calif. Awards $45M in Stem Cell Grants Associated Press, Feb. 17, 2007.
[edit] External links
General
Tell Me About Stem Cells: Quick and simple guide explaining the science behind stem cells
Stem Cell Basics
Nature Reports Stem Cells: Introductory material, research advances and debates concerning stem cell research.
Understanding Stem Cells: A View of the Science and Issues from the National Academies
Scientific American Magazine (June 2004 Issue) The Stem Cell Challenge
Scientific American Magazine (July 2006 Issue) Stem Cells: The Real Culprits in Cancer?
National Institutes of Health
Stem Cell Research Forum of India
Ethics of Stem Cell Research entry at the Stanford Encyclopedia of Philosophy by Andrew Siegel
Peer-reviewed journals
STEM CELLS®
Cytotherapy
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Astrocytomas
Astrocytomas are tumors that arise from astrocyle cells, which is part of the supportive (neuroepithelial) tisue of the brain.
These cells are named for their starlike shape. These are the most common primary CNS tumors, representing about half of brain and spinal cord tumors.
The most frequent types of astrocytma, in increasing degress of grade, are the pilocytic astrocytoma (grade I), astrocytoma (grade II). anaplastic astrocytoma (grade III.) and glioblastonia miltiforme(grade IV). If the tumor also contains oligodendrogltoma and/or ependymoma cells, it is called a mixed glioma.
Low-Grade Astrocytoma
Pilocytic astrocytomas and subependymal giant cell astrocytomas are grade I tumors. These non-infiltrating tumors occasionally form cysts or are enclosed in a cyst. Metastasis or a secondary malignant tumor is rare. Although they are slow-growing, these tumors can become very large. Grade I tumors are often effectively treated by surgery alone.
Radiation therapy may be given for incompletely removed tumors. If the tumor recurs, reoperation and some form of radiation are options. Pilocytic astrocytomas occur mainly in children. They are the most benign of the astrocytonias. Cerebellar astrocytomas and optic tract gliomas are often pilocytic tumors.
Grade II tumors include low-grade astrocytoma, fibrillary or protoplasmic astrocytoma and some pleomorphic xanthoastrocytonias. They are usually infiltrating tumors but grow relatively slowly.
A tumor's location often determines its treatment. Complete surgical removal is sometimes possible for accessible tumors, although they can be locally invasive. If total surgical removal is thought to have been achieved, periodic follow-up with MRI or CT scans may be the only additional care required.
External beam whole brain radiation therapy is often used in addition to surgery (partial resection) or for inoperable low-grade astrocytomas. If necessary, Gamma Knife may be utilized as a boost to surgery and radiation where total removal of the tumor was not accomplished. European studies and our own experience has shown good results using implanted seeds of irradiation with permanent implants. Children younger than 3 years old may receive chemotherapy so that radiation or radiation seed implants can be delayed.
Again, stereotactic radiosurgery or Ganima Knife may be assessed as an alternative.
Anaplastic Astrocytoma
Anaplastic astrocytoma, sometimes called grade III malignant tumors, are tumors that grow more rapidly than low grade tumors and tend to invade nearby healthy tissue. They recur more frequently and more quickly than some lower grade tumors because their tendency to spread into surrounding tissue makes it difficult to completely remove them during surgery. An Anaplastic Astrocytonia can be a reoccurrence from a lower grade of an already treated astro-Cytonia tumor.
Treatment recommendations for these types of tumors are based on the tumor's location, if the tumor has spread. how far it has spread and the patient's general health and age. Surgery followed by conventional external beam radiation therapy is the primary treatment for accessible mid-grade astrocytomas. Boost radiation using interstitial or radiation seeds implanted directly into the tumor site has shown promising results in our experience. Chemotherapy-may be recommended after surgery and/or radiation therapy. Gamma Knife has been increasingly shown to be beneficial as a boost to conventional radiation in the control of these tumors.
BCNU, a commonly used drug, or the combination of procarbazine, CCNU and vincristine (PCV) have also shown promising results.
Glioblastoma multiforme
By definition, a glioblastoma multiforme (GBM) tumor is considered a grade IV tumor. This high-grade astrocytoma group is represented by the glioblastoma multiforme and variants. the gliosarcoma and giant cell glioblastoma. A malignant astrocytoma that contains areas of dead tumor cells (necrosis) is called a glioblastoma multiforme. GBM represents about 30 percent of all primary brain tumors and about-50 percent of the astrocytomas. It is more common in older adults and it affects more men than women. Nine percent of childhood brain tumors are glioblastomas.
Because of its aggressive nature and fast growing ability, the first symptoms are usually due to increased pressure in the brain. Headaches, seizures, memory loss and behavioral changes are the most common presenting symptoms. The first procedure for most GBMs is either surgery to remove the tumor, or a biopsy for diagnosis. Surgery alone rarely controls the GBM because of its aggressive nature whereby its cells quickly infiltrate throughout the brain. Thus, radiation therapy almost always follows surgery or biopsy to attempt to control the spread of the cells.
These cells are named for their starlike shape. These are the most common primary CNS tumors, representing about half of brain and spinal cord tumors.
The most frequent types of astrocytma, in increasing degress of grade, are the pilocytic astrocytoma (grade I), astrocytoma (grade II). anaplastic astrocytoma (grade III.) and glioblastonia miltiforme(grade IV). If the tumor also contains oligodendrogltoma and/or ependymoma cells, it is called a mixed glioma.
Low-Grade Astrocytoma
Pilocytic astrocytomas and subependymal giant cell astrocytomas are grade I tumors. These non-infiltrating tumors occasionally form cysts or are enclosed in a cyst. Metastasis or a secondary malignant tumor is rare. Although they are slow-growing, these tumors can become very large. Grade I tumors are often effectively treated by surgery alone.
Radiation therapy may be given for incompletely removed tumors. If the tumor recurs, reoperation and some form of radiation are options. Pilocytic astrocytomas occur mainly in children. They are the most benign of the astrocytonias. Cerebellar astrocytomas and optic tract gliomas are often pilocytic tumors.
Grade II tumors include low-grade astrocytoma, fibrillary or protoplasmic astrocytoma and some pleomorphic xanthoastrocytonias. They are usually infiltrating tumors but grow relatively slowly.
A tumor's location often determines its treatment. Complete surgical removal is sometimes possible for accessible tumors, although they can be locally invasive. If total surgical removal is thought to have been achieved, periodic follow-up with MRI or CT scans may be the only additional care required.
External beam whole brain radiation therapy is often used in addition to surgery (partial resection) or for inoperable low-grade astrocytomas. If necessary, Gamma Knife may be utilized as a boost to surgery and radiation where total removal of the tumor was not accomplished. European studies and our own experience has shown good results using implanted seeds of irradiation with permanent implants. Children younger than 3 years old may receive chemotherapy so that radiation or radiation seed implants can be delayed.
Again, stereotactic radiosurgery or Ganima Knife may be assessed as an alternative.
Anaplastic Astrocytoma
Anaplastic astrocytoma, sometimes called grade III malignant tumors, are tumors that grow more rapidly than low grade tumors and tend to invade nearby healthy tissue. They recur more frequently and more quickly than some lower grade tumors because their tendency to spread into surrounding tissue makes it difficult to completely remove them during surgery. An Anaplastic Astrocytonia can be a reoccurrence from a lower grade of an already treated astro-Cytonia tumor.
Treatment recommendations for these types of tumors are based on the tumor's location, if the tumor has spread. how far it has spread and the patient's general health and age. Surgery followed by conventional external beam radiation therapy is the primary treatment for accessible mid-grade astrocytomas. Boost radiation using interstitial or radiation seeds implanted directly into the tumor site has shown promising results in our experience. Chemotherapy-may be recommended after surgery and/or radiation therapy. Gamma Knife has been increasingly shown to be beneficial as a boost to conventional radiation in the control of these tumors.
BCNU, a commonly used drug, or the combination of procarbazine, CCNU and vincristine (PCV) have also shown promising results.
Glioblastoma multiforme
By definition, a glioblastoma multiforme (GBM) tumor is considered a grade IV tumor. This high-grade astrocytoma group is represented by the glioblastoma multiforme and variants. the gliosarcoma and giant cell glioblastoma. A malignant astrocytoma that contains areas of dead tumor cells (necrosis) is called a glioblastoma multiforme. GBM represents about 30 percent of all primary brain tumors and about-50 percent of the astrocytomas. It is more common in older adults and it affects more men than women. Nine percent of childhood brain tumors are glioblastomas.
Because of its aggressive nature and fast growing ability, the first symptoms are usually due to increased pressure in the brain. Headaches, seizures, memory loss and behavioral changes are the most common presenting symptoms. The first procedure for most GBMs is either surgery to remove the tumor, or a biopsy for diagnosis. Surgery alone rarely controls the GBM because of its aggressive nature whereby its cells quickly infiltrate throughout the brain. Thus, radiation therapy almost always follows surgery or biopsy to attempt to control the spread of the cells.
Acoustic Neuroma
Definition: This is an intra-cranial (within the head but outside the brain) tumor that arises from the superior vestibular nerve (a nerve for balance). The more accurate term is therefore vestibular schwannoma.
Histopathology: They are firm and encapsulated and classified as benign. Antoni A and Antoni B biphasic patterns are found. They can be cystic, hemorrhagic or entirely solid tumors. Malignancy is rare.
Location: It starts in the internal acoustic meatus but can grow medially towards the brainstem and occupy space in the cerebellopontine angle.
Related tumors: Trigeminal schwannoma and the rare facial nerve schwannoma can occur in the same location (CP angle).
Symptoms / Presentation: This includes tinnitus (ringing in the ears), hearing loss, imbalance, numbness of the face (caused by compressing nerves, brainstem and cerebellum in the CP angle as the tumor grows). Large tumors may cause hydrocephalus by obstructing CSF circulation and this may cause symptoms related to this condition.
Diagnosis: It can be overlooked in the early stages and the diagnosis missed as tinnitus and mild hearing loss are often not investigated with MRI scanning. The best single test is MRI of the brain and IAM (internal acoustic meatus) with contrast (gadolinium). Hearing and balance tests can document the effects of the tumor.
Treatment: There are in general, three options: Monitoring of small tumors (< 1cm in size) if hearing is still intact is an option in older patients and in younger patients with bilateral tumors associated with NF (Neurofibromatosis, NF-2). This includes clinical and hearing tests supplemented with regular MRI scans. If the tumor increases in size and significant hearing loss occurs treatment is recommended.
Surgery and tumor excision was once the only treatment option for most of the 20th century. Microsurgery, improved anesthesiology, Image-guidance , better microsurgical tools and nerve monitoring have improved the results of surgery. Microsurgery may still be the best treatment option for large tumors (>3.5cm) in selected patients who have symptoms from the mass effect of the tumor.
Radiosurgery is now an accepted treatment modality for acoustic neuromas as there is overall a lower risk than surgery in terms of anesthesia risks, bleeding and infection. Mortality which is a possibility with any brain surgery is extremely rare and even exceptional with modern radiosurgery/stereotactic radiotherapy. In addition numerous centers and clinical papers have documented the safety and effectiveness of Radiosurgery. Newer forms of radiosurgery include Micro-MLC radiosurgery, fractionated radiosurgery (also referred to as Stereotactic Radiotherapy and vice versa) and NeuroTomotherapy.
Combined Microsurgery and Radiosurgery (CMR) is an option that can work well with large acoustic neuromas. Microsurgery is used to remove tumor in a safe way without damaging near by nerves (especially the facial nerve and trigeminal nerve and the brainstem) and any remaining smaller volume tumor is then treated subsequently with radiosurgery / SRT / FSR / NeuroTomotherapy.
by.http://www.drprempillay.com/ind/services_acoustic_neuroma.htm
Histopathology: They are firm and encapsulated and classified as benign. Antoni A and Antoni B biphasic patterns are found. They can be cystic, hemorrhagic or entirely solid tumors. Malignancy is rare.
Location: It starts in the internal acoustic meatus but can grow medially towards the brainstem and occupy space in the cerebellopontine angle.
Related tumors: Trigeminal schwannoma and the rare facial nerve schwannoma can occur in the same location (CP angle).
Symptoms / Presentation: This includes tinnitus (ringing in the ears), hearing loss, imbalance, numbness of the face (caused by compressing nerves, brainstem and cerebellum in the CP angle as the tumor grows). Large tumors may cause hydrocephalus by obstructing CSF circulation and this may cause symptoms related to this condition.
Diagnosis: It can be overlooked in the early stages and the diagnosis missed as tinnitus and mild hearing loss are often not investigated with MRI scanning. The best single test is MRI of the brain and IAM (internal acoustic meatus) with contrast (gadolinium). Hearing and balance tests can document the effects of the tumor.
Treatment: There are in general, three options: Monitoring of small tumors (< 1cm in size) if hearing is still intact is an option in older patients and in younger patients with bilateral tumors associated with NF (Neurofibromatosis, NF-2). This includes clinical and hearing tests supplemented with regular MRI scans. If the tumor increases in size and significant hearing loss occurs treatment is recommended.
Surgery and tumor excision was once the only treatment option for most of the 20th century. Microsurgery, improved anesthesiology, Image-guidance , better microsurgical tools and nerve monitoring have improved the results of surgery. Microsurgery may still be the best treatment option for large tumors (>3.5cm) in selected patients who have symptoms from the mass effect of the tumor.
Radiosurgery is now an accepted treatment modality for acoustic neuromas as there is overall a lower risk than surgery in terms of anesthesia risks, bleeding and infection. Mortality which is a possibility with any brain surgery is extremely rare and even exceptional with modern radiosurgery/stereotactic radiotherapy. In addition numerous centers and clinical papers have documented the safety and effectiveness of Radiosurgery. Newer forms of radiosurgery include Micro-MLC radiosurgery, fractionated radiosurgery (also referred to as Stereotactic Radiotherapy and vice versa) and NeuroTomotherapy.
Combined Microsurgery and Radiosurgery (CMR) is an option that can work well with large acoustic neuromas. Microsurgery is used to remove tumor in a safe way without damaging near by nerves (especially the facial nerve and trigeminal nerve and the brainstem) and any remaining smaller volume tumor is then treated subsequently with radiosurgery / SRT / FSR / NeuroTomotherapy.
by.http://www.drprempillay.com/ind/services_acoustic_neuroma.htm
Gene Activity May Explain Deadlier Breast Cancers Among Younger Women
Study finds more than 350 common sets of genes in patients under 45
By Amanda Gardner
HealthDay Reporter
WEDNESDAY, July 9 (HealthDay News) -- Genetic activity in breast cancer cells from younger patients could explain why tumors tend to more aggressive when they strike at a younger age.
"We haven't had a good reason why younger women do worse than older women," said senior study author Dr. Kimberly Blackwell, director of the clinical trials program in breast cancer at Duke University. "This study offers some insight into why younger women do worse."
"This is a real testament that we're beginning to define, from a molecular basis, why certain patients do so poorly," said Dr. Jay Brooks, chairman of hematology/oncology at Ochsner Health System in Baton Rouge, La. "I think this will go a long way to helping define a population that, hopefully, would have more aggressive treatments."
The results are in the July 10 issue of the Journal of Clinical Oncology.
Breast cancer tends to be more aggressive in younger women, responds less well to existing treatments such as radiation, surgery and chemotherapy, and has higher recurrence and lower survival rates.
"You think of breast cancer as sort of like a mosaic pattern with certain patterns that are very bad and certain patterns that are very good," said Dr. Otis Brawley, chief medical officer of the American Cancer Society. "You're talking about 600 different genes in the mosaic patterns, and you end up with certain cancers that are very aggressive and some cancers that are not so aggressive. We tend to see more aggressive cancers in younger women versus older women."
"We've known for 60 or 70 years that cancers tended to be more aggressive in younger women," Brawley said. "Now we're actually looking at the genetics."
For this study, Duke researchers analyzed samples of almost 800 early-stage breast tumors in two groups of women: those aged 45 and under and those aged 65 or older.
More than 350 sets of genes were activated only in the younger women. Tumors in older patients did not share any common gene sets, the authors stated.
The gene sets activated in younger women regulated such things as immune function, breast cancer-related gene mutations such as BRCA1, stem cell biology, cell death and various cancer signaling pathways.
Younger women were less likely to have estrogen-receptor-positive tumors (71 percent versus 80 percent in older women); more likely to have tumors which overexpress the protein HER2neu (52 percent versus 24 percent); more likely to have higher-grade tumors (56 percent versus 26 percent) and larger tumor size; more likely to have positive lymph nodes (38 percent versus 25 percent); and higher recurrence rates.
Women under 40 had even higher recurrence rates than women aged 40 to 45, although there appeared to be no differences in subgroups of women under the age of 40.
Compounds already in development may hold promise for treating younger women, the authors said, although the actual benefit for patients may be some years away.
"This doesn't mean anything for a young woman who has breast cancer [now], like the one that I saw yesterday afternoon," Brawley said. "It does mean that perhaps in five years, perhaps in 10, we will have more drugs like Herceptin. A study like this gives you the target."
Herceptin targets tumors which overexpress the HER2neu protein.
More information
The American Cancer Society has more on breast cancer.
By Amanda Gardner
HealthDay Reporter
WEDNESDAY, July 9 (HealthDay News) -- Genetic activity in breast cancer cells from younger patients could explain why tumors tend to more aggressive when they strike at a younger age.
"We haven't had a good reason why younger women do worse than older women," said senior study author Dr. Kimberly Blackwell, director of the clinical trials program in breast cancer at Duke University. "This study offers some insight into why younger women do worse."
"This is a real testament that we're beginning to define, from a molecular basis, why certain patients do so poorly," said Dr. Jay Brooks, chairman of hematology/oncology at Ochsner Health System in Baton Rouge, La. "I think this will go a long way to helping define a population that, hopefully, would have more aggressive treatments."
The results are in the July 10 issue of the Journal of Clinical Oncology.
Breast cancer tends to be more aggressive in younger women, responds less well to existing treatments such as radiation, surgery and chemotherapy, and has higher recurrence and lower survival rates.
"You think of breast cancer as sort of like a mosaic pattern with certain patterns that are very bad and certain patterns that are very good," said Dr. Otis Brawley, chief medical officer of the American Cancer Society. "You're talking about 600 different genes in the mosaic patterns, and you end up with certain cancers that are very aggressive and some cancers that are not so aggressive. We tend to see more aggressive cancers in younger women versus older women."
"We've known for 60 or 70 years that cancers tended to be more aggressive in younger women," Brawley said. "Now we're actually looking at the genetics."
For this study, Duke researchers analyzed samples of almost 800 early-stage breast tumors in two groups of women: those aged 45 and under and those aged 65 or older.
More than 350 sets of genes were activated only in the younger women. Tumors in older patients did not share any common gene sets, the authors stated.
The gene sets activated in younger women regulated such things as immune function, breast cancer-related gene mutations such as BRCA1, stem cell biology, cell death and various cancer signaling pathways.
Younger women were less likely to have estrogen-receptor-positive tumors (71 percent versus 80 percent in older women); more likely to have tumors which overexpress the protein HER2neu (52 percent versus 24 percent); more likely to have higher-grade tumors (56 percent versus 26 percent) and larger tumor size; more likely to have positive lymph nodes (38 percent versus 25 percent); and higher recurrence rates.
Women under 40 had even higher recurrence rates than women aged 40 to 45, although there appeared to be no differences in subgroups of women under the age of 40.
Compounds already in development may hold promise for treating younger women, the authors said, although the actual benefit for patients may be some years away.
"This doesn't mean anything for a young woman who has breast cancer [now], like the one that I saw yesterday afternoon," Brawley said. "It does mean that perhaps in five years, perhaps in 10, we will have more drugs like Herceptin. A study like this gives you the target."
Herceptin targets tumors which overexpress the HER2neu protein.
More information
The American Cancer Society has more on breast cancer.
Secretary's Advisory Committe On National Health Promotion & Desease Prevention Objectivies 2020
The Secretary’s Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 will hold its fourth meeting July 30, 2008 on the Internet via WebEx. The purpose of the meeting is to allow the full committee to continue its deliberations and to hear reports from its various subcommittees. An agenda will be posted before the meeting. This meeting will be open to the public for listening. Please select the "Register to Attend" icon for more information and to register for the meeting.
To attend the July 30 meeting via WebEx, individuals must officially register online. Advance registration is now open and will close July 29 at 5:00 P.M. EDT.
First Meeting
The first meeting of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 was held on January 31 and February 1, 2008. The meeting agenda areand a list of Committee members are available online. A meeting summary will be posted soon. Please check back.
The 2-day meeting took place at:
The U.S. Department of Health and Human ServicesHubert H. Humphrey Building, Room 800200 Independence Avenue, S.W.Washington, D.C. 20201Thursday, January 31, 2008: 9:00 A.M. to 5:30 P.M. Friday, February 1, 2008: 8:30 A.M. to 5:00 P.M.
Second Meeting
The second meeting of the Advisory Committee was held May 1, 2008 on the Internet via WebEx. Read the meeting minutes.
Third Meeting
The third meeting of the Advisory Committee was held June 5-6, 2008 in Arlington, VA. A meeting summary will be posted soon. Please check back.
Federal Register Notice: July 9, 2008Announcement of the Fourth Meeting of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 [PDF version - 52k]
Federal Register Notice: May 19, 2008Announcement of Third Meeting of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 [PDF version - 44k]
Federal Register Notice: April 14, 2008Announcement of Second Meeting of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 [PDF version - 52k]
Press Release: February 1, 2008HHS Secretary Leavitt Announces Members of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020
Federal Register Notice: January 15, 2008Announcement of First Meeting of the Secretary’s Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 [PDF version - 54k]
Federal Register Notice: August 21, 2007Announcement of Establishment of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 and Solicitation of Nominations for Membership [PDF version - 51k]
Note: Documents in PDF format require the Adobe Acrobat Reader®. If you experience problems with PDF documents, please download the latest version of the Reader®.
Content for this site is maintained by the Office of Disease Prevention & Health Promotion, U.S. Department of Health and Human Services.
To attend the July 30 meeting via WebEx, individuals must officially register online. Advance registration is now open and will close July 29 at 5:00 P.M. EDT.
First Meeting
The first meeting of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 was held on January 31 and February 1, 2008. The meeting agenda areand a list of Committee members are available online. A meeting summary will be posted soon. Please check back.
The 2-day meeting took place at:
The U.S. Department of Health and Human ServicesHubert H. Humphrey Building, Room 800200 Independence Avenue, S.W.Washington, D.C. 20201Thursday, January 31, 2008: 9:00 A.M. to 5:30 P.M. Friday, February 1, 2008: 8:30 A.M. to 5:00 P.M.
Second Meeting
The second meeting of the Advisory Committee was held May 1, 2008 on the Internet via WebEx. Read the meeting minutes.
Third Meeting
The third meeting of the Advisory Committee was held June 5-6, 2008 in Arlington, VA. A meeting summary will be posted soon. Please check back.
Federal Register Notice: July 9, 2008Announcement of the Fourth Meeting of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 [PDF version - 52k]
Federal Register Notice: May 19, 2008Announcement of Third Meeting of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 [PDF version - 44k]
Federal Register Notice: April 14, 2008Announcement of Second Meeting of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 [PDF version - 52k]
Press Release: February 1, 2008HHS Secretary Leavitt Announces Members of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020
Federal Register Notice: January 15, 2008Announcement of First Meeting of the Secretary’s Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 [PDF version - 54k]
Federal Register Notice: August 21, 2007Announcement of Establishment of the Secretary's Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020 and Solicitation of Nominations for Membership [PDF version - 51k]
Note: Documents in PDF format require the Adobe Acrobat Reader®. If you experience problems with PDF documents, please download the latest version of the Reader®.
Content for this site is maintained by the Office of Disease Prevention & Health Promotion, U.S. Department of Health and Human Services.
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