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Minggu, 07 Juni 2009

Kisspeptin Hormon baru untuk kesuburan

Tim peneliti dari imperial college London baru-baru ini menemukan hormone yang dapat membentuk basis pengobatan kesuburan yang efektif dan tanpa resiko. Penemuan yang disebut dengan kisspeptin itu dapat memperbarui fungsi reproduksi pada wanita, dengan level hormone seks rendah yang sistemnya telah ditutup. Hormone tersebut melahirkan peran penting dalam menstimulasi pelepasan hormone yang mengotrol siklus menstruasi.
Sebelumnya para peneliti ini menunjukkan pengobatan kisspeptin untuk mendorong produksi hormone seks pada wanita subur. Kini merekan memperluas penelitian untuk melihat efek kisspeptin pada wanita ketika periode menstruasi telah berhenti karena ketidakseimbangan hormone.
Penelitian terakhir melibatkan kelompok terdiri dari 10 wanita yang tidak menstruasi dan tidak subur. Para wanita itu disuntik dengan kisspeptin. Kemudian sample darah 10 wanita diteliti untuk diukur level dua hormone kunci mereka. Kedua hormone yang dikenal dengan nama luteinizing hormone (LH) dan follicle stimulating hormone (FSH) itu sangat berperan penting dalam ovulasi dan kesuburan.
Jika dibandingkan dengan pengobata placebo, kisspeptin menunjukkan peningkatan 48 kali lipat pada LH dan 16 kali lipat pada FSH. Pimpinan peneliti Dr. waljit Dhilo menjelaskan pengobatan kisspeptin bisa menstimulasi penambahan yang lebih hebat pada produksi LH wanita yang tidak menstruasi jika dibandingkan dengan wanita subur pada penelitian sebelumnya. Menurutnya, ketidaksuburan adalah kondisi rusak yang mempengaruhi jutaan pasangan di seluruh dunia. Terbukti bahwa pengobatan kisspeptin dapat memperbarui fungsi reproduksi wanita dengan lovel hormone seks rendah.


Sumber : Harian Media Indonesia, Minggu 22 maret 2009

Sabtu, 14 Maret 2009

Vitamin D dan Remaja

Hasil penelitian terbaru mengungkapkan bahwa remaja yang kekurangan vitamin D berisiko terkena gangguan jantung, diabetes,

Dan tekanan darah tinggi. Hal itu disampaikan para peneliti pada pertemuan tahunan American heart association baru-baru ini ( 2009).

Peneliti juga menemukan remaja berkulit putih di AS memiliki vitamin D yang lebih tinggi dua kali lipat jika dibandingkan dengan remaja Afrika-amerika dan sekitar 30% lebih tinggi ketimbang remaja amerika-meksiko.

“Data menunjukkan bahwa serum vitamin D pada anak muda meningkatkan perhatian mengenai pilihan makan mereka dan jumlah waktu yang mereka habiskan untuk terpapar sinar matahari,” kata Robert eckel, mantan direktur American heart association.

Tubuh akan memproduksi Vitamin D ketika terpapar sinar matahari. Selain itu, vitamin D dapat ditemukan pada sejumlah makanan dan minuman, di antaranya ikan, telur, dan susu.

Hasil penelitian tesebut melengkapi fungsi vitamin D yang sudah familier, yakni membantu melindungi tulang yang kuat dari penyerapan kalsium.

Sumber : Harian Media Indonesia

Low Vitamin D Hurts Teens' Hearts

Low Vitamin D Raises Teens' Risk of Diabetes, Heart Disease

By Daniel J. DeNoon
WebMD Health News

Reviewed By Elizabeth Klodas, MD, FACC

March 11, 2009 -- Low vitamin D levels greatly increase a teenager's risk of diabetes and heart disease, Johns Hopkins researchers find.

It is becoming clear that adults who get too little vitamin D are at higher risk for diabetes and heart disease. Now, it appears vitamin D levels also affect these risks earlier in life, say Johns Hopkins researchers Jared P. Reis, PhD, and colleagues.

The researchers analyzed data from 3,577 adolescents aged 12 to 19 enrolled in National Health and Nutrition Examination surveys from 2001 through 2004.

Compared to the 25% of teens with the highest levels of vitamin D in their blood (more than 26 nanograms per milliliter), the 25% of teens with the lowest vitamin D levels (less than 15 ng/mL) had:

Black teens averaged about half the vitamin D levels seen in white teens (15.5 ng/mL vs. 28.0 ng/mL).

Although the findings suggest that vitamin D supplements would be helpful, Reis warns that it remains to be proven whether this would reduce diabetes and heart disease risk.

"We believe clinical trials designed to determine the effects of vitamin D supplementation on heart disease risk factors in adolescents should be conducted before recommendations can be made for vitamin D in the prevention of cardiovascular disease," Reis says in a news release.

And supplements may not be the best way to get vitamin D, suggests American Heart Association past president Robert H. Eckel, MD.

"The AHA recommends an overall healthy diet and lifestyle, and that people get their nutrients primarily from food sources rather than supplements," Eckel says in the news release.

How much vitamin D is enough? That's still being debated. The American Academy of Pediatrics recently suggested a daily intake of 400 IU. But some experts say children and teens need more than 1,000 IU of vitamin D every day.

People who are obese are more likely to have vitamin D deficiency than normal-weight people. Reis suggests this may be because vitamin D is fat soluble and gets tucked away in fat tissue.

"We are just now starting to understand the role that vitamin D may play in cardiovascular health," Reis says.

Reis reported the findings at this week's American Heart Association meeting in Palm Harbor, Fla.

SOURCES: American Heart Association Scientific Conferences, Palm Harbor, Fla., March 10-14, 2009. News release, American Heart Association. WebMD Health News: " Kids May Need 10 Times More Vitamin D," May 28, 2008. WebMD Health News: " Supplement Your Knowledge of Vitamin D," May 19, 2008.

©2009 WebMD, LLC. All Rights Reserved.

sunber : Emedicinehealth.com

Rabu, 11 Maret 2009

Vitamin C May Help Prevent Gout


Study Shows Vitamin C From Food or Supplements May Reduce the Risk of Gout

By Jennifer Warner
WebMD Health News

Reviewed By Louise Chang, MD

March 9, 2009 -- Boosting vitamin C intake may be a simple way to help prevent one of the most common forms of arthritis.

A new study shows the vitamin better known for fighting colds may also prevent gout.

Researchers found men who had the highest vitamin C intake from supplements and food were up to 45% less likely to develop the painful condition than those who had the lowest.

Vitamin C is found naturally in citrus fruit, broccoli, and other fruits and vegetables; it is often taken in supplement form.

Researcher Hyon K. Choi, MD, formerly of the University of British Columbia, Vancouver, and now of the Boston University School of Medicine, and colleagues say other studies have suggested that vitamin C appears to prevent gout by reducing levels of uric acid in the blood. Buildup of uric acid can lead to the formation of crystals, which can deposit in the body, leading to the pain, inflammation, and swelling associated with gout.

In the study, published in the Archives of Internal Medicine, researchers analyzed the relationship between vitamin C intake and gout among 46,994 healthy men from 1986 to 2006. The men answered questionnaires detailing vitamin C intake through diet and/or vitamin C supplements every four years.

During the study period, 1,317 new cases of gout were diagnosed among the participants.

The results showed that those with higher vitamin C intake had a consistently lower risk of developing gout than others. For example, men with a vitamin C intake of 1,500 milligrams or more per day had a 45% lower risk of gout compared with those who had a vitamin C intake of less than 250 milligrams per day.

Nearly all the men who had vitamin C intakes over 500 milligrams per day took vitamin C supplements. Researchers found that for every 500 milligrams of vitamin C the men took, the risk of gout was reduced by an additional 15%.

Researchers say the results suggest that taking vitamin C supplements at the levels in the study (less than 2,000 milligrams per day) may be a safe and effective way to prevent gout.

SOURCES: Choi, H. Archives of Internal Medicine, March 9, 2009; vol 169: pp 502-507. News release, American Medical Association.

©2009 WebMD, LLC. All Rights Reserved.

Jumat, 06 Maret 2009

High Blood Sugar Linked to Memory Loss


Taking Steps to Lower Blood Sugar May Protect Against Age-Related Memory Loss

By Salynn Boyles
WebMD Health News

Reviewed By Louise Chang, MD

Dec. 30, 2008 -- Maintaining normal blood sugar levels as we age may protect against more than diabetes. It may also help prevent age-related memory loss, a new study shows.

Using high-resolution brain imaging, researchers showed that rising blood sugar levels selectively target a key area of the brain linked to memory decline.

The finding suggests that interventions to improve blood sugar, such as getting regular exercise and eating a healthy diet, may help both the body and the brain as it ages.

"We have known that exercise improves blood sugar and that it helps prevent age-related memory loss," says lead researcher Scott Small, MD, of Columbia University Medical Center. "In this study, we were able to show the specific area of the brain that is impacted by rising blood sugar."

Blood Sugar and Memory

Focusing on the hippocampus -- the area of the brain associated with memory and learning -- Small and colleagues previously identified a section that was most associated with age-related memory decline.

In their newly published study, the researchers looked at how this area, known as the dentate gyrus, is affected by changes typically seen with aging, such as rising cholesterol, body weight, and blood sugar.

Human and animal imaging studies confirmed that rising blood sugar was the only change directly associated with decreased activity in the dentate gyrus.

Because blood sugar levels tend to rise with age, the finding suggests that monitoring and taking steps to lower blood sugar as we grow older may be an important strategy for preventing age-related cognitive decline for everyone, not just people with diabetes, Small tells WebMD.

The study was funded by the National Institute on Aging, the American Diabetes Association, and the McKnight Brain Research Foundation. It appears in the December issue of the journal Annals of Neurology.

"Beyond the obvious conclusion that preventing late-life disease would benefit the aging hippocampus, our findings suggest that maintaining blood sugar levels, even in the absence of diabetes, could help maintain aspects of cognitive health," Small says in a news release.

Exercise Lowers Blood Sugar

Because exercise improves the ability of the muscles to process glucose, it makes sense that it helps protect cognitive function as we age, Small says.

Linda Nichol, PhD, of the National Institute on Aging, tells WebMD that the research may help explain why diabetic people are at increased risk of developing Alzheimer's disease.

She says studies are under way to determine if drugs that regulate blood sugar can help slow cognitive declines in people with early evidence of the disease.

It is far too soon to say if people who don't have diabetes might benefit from taking the drugs as they get older, she says.

"We already know that physical exercise can help people stay cognitively sharp as they age," she adds. "This study may help explain why."

SOURCES: Small, S.A. Annals of Neurology, December 2008; online edition. Scott A. Small, MD, associate professor of neurology, Sergievsky Center, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York. Linda Nichols, PhD, program director, Alzheimer's Clinical Trials, Division of Neuroscience, National Institute on Aging.

©2008 WebMD, LLC. All Rights Reserved.

Sabtu, 21 Februari 2009

Top Health Risks for Young Adults

Accidents Are the Leading Cause of Death; Long-Term Health Risks Include Smoking, Obesity, Inactivity

By Miranda Hitti
WebMD Health News

Reviewed By Louise Chang, MD

Feb. 18, 2009 -- Youth is often painted as a time of picture-perfect health, but that's not necessarily reality, a new CDC report shows.

The CDC today released its latest roundup of U.S. health statistics, with a special focus on young adults 18-29.

Highlights of the findings on young adults include:

  • Top cause of death: Unintentional injuries, which killed about 40 per 100,000 young adults in 2005.
  • Smoking: 29% of men and 21% of women 18-29 smoke cigarettes as of 2006.
  • Obesity: 24% of young adults are obese, and 28% more are overweight but not obese as of 2005-2006. Obesity rates for young adults tripled between 1971-1974 and 2005-2006.
  • Regular physical activity: Only 36% of young adults get regular physical activity in their spare time as of 2005-2006. That's better than the rate for older adults but below national goals.
  • Strength training at least twice per week: Done by only 26% of young adults in 2005-2006.
  • No health insurance: About a third of young adults 20-24 were uninsured in 2006.

The new CDC report, which is more than 600 pages long, isn't only about young adults. Here's a quick look at some of the health stats for the nation as a whole:

  • Life expectancy is up. As the CDC first reported last year, life expectancy for babies born in 2006 is 78.1 years, a record high. Life expectancy is still lower for men than for women and for African-Americans than for whites, but those gaps are narrowing. And among 37 countries and territories that submitted life expectancy data in 2004, the U.S. ranked 23rd for men and 25th for women (Hong Kong was No. 1 for men and Japan was No. 1 for women.)
  • Top causes of death: Deaths from heart disease, stroke, and cancer continue to drop but are still the nation's top three causes of death.
  • Obesity: Still rising, but more slowly than in past decades. More than one-third of adults aged 20 and older are obese as of 2005-2006.
  • Aging: People aged 75 and older made up 6% of the national population in 2006 and their ranks will double by 2050, the CDC predicts.

SOURCES: CDC: "Health, United States, 2008." News release, CDC.

©2009 WebMD, LLC. All Rights Reserved.

Heart Attack Care: Drugs vs. Stents

Analysis Shows Drugs After Heart Attack Are Effective and Reduce Costs

By Salynn Boyles
WebMD Health News

Reviewed By Elizabeth Klodas, MD, FACC

Feb. 18, 2009 -- Opening blocked arteries with balloon angioplasty and stents can save lives during a heart attack, but the invasive treatment offers little added value over heart drugs alone in patients first treated days and even weeks later.

Now a new analysis shows that avoiding stenting in stable late-presenting patients could result in a yearly savings of around $700 million in health care costs.

"What we have here is one of those cases where less is more," says researcher Daniel B. Mark, MD, MPH, of Duke University Medical Center.

Stents Most Useful Early

Clearing blocked arteries in the early stages of a heart attack can restore blood flow before heart muscle is permanently damaged.

But as many as a third of the roughly 1 million Americans who have heart attacks each year are treated more than 12 hours after their first symptoms appear, when heart damage is likely to have already occurred, Mark tells WebMD.

Clot-busting drugs are not an option when treatment is delayed, but bare metal or drug-coated metal stents were often implanted to prop open and clear blocked arteries in late-presenting patients, even when they had no angina (chest pain) or other physical symptoms.

In the Occluded Artery Trial (OAT), a major, federally funded study published two years ago, Mark and colleagues reported that late-presenting heart attack patients with blocked arteries had no better long-term outcomes when they were treated with balloon angioplasty and stents than when treated with drugs alone. These results led to major changes in the management of such patients by many cardiologists.

All of the patients enrolled in OAT were clinically stable with no chest pain, and all received appropriate medical treatment with drugs like aspirin, beta-blockers, ACE inhibitors, and statins.

Quality of Life and Treatment Costs

In a new report, published in the Feb. 19 issue of the New England Journal of Medicine, Mark and colleagues further analyzed the OAT data.

They examined quality-of-life measurements and treatment costs among the two treatment groups.

Quality of life was determined through standardized questionnaires administered either face-to-face or by telephone at enrollment and at 4, 12, and 24 months.

Four months after enrollment, the stent patients did report less chest pain and scored higher on quality-of-life assessments. But the differences were small and they had disappeared altogether within a year, Mark says.

"We saw no discernable differences in what patients said they were able to do or in any other major measure of quality of life and well-being," he says.

The average cost of hospital and physician care during the first 30 days of treatment was calculated to be $22,859 per patient treated with balloon angioplasty and stenting vs. $12,683 for the medical therapy group.

Over two years of treatment, medical costs among patients treated with angioplasty and stents were an average of $7,000 higher than patients who did not get angioplasty and stents.

It should be emphasized again that the patients enrolled in the OAT trial were all stable and without symptoms. Balloon angioplasty and stenting "does not appear beneficial for this highly selected group ... but that doesn't mean that patients who are very impaired or have poor quality of life and angina will not benefit," study researcher Judith S. Hochman, MD, of New York University School of Medicine, tells WebMD.

National Heart Lung and Blood Institute senior cardiologist George Sopko, MD, tells WebMD that the OAT trial highlights the importance of seeking treatment early when heart attack symptoms occur.

"When someone is having a heart attack, time is of the essence," he says. "We know that if we can reopen blocked arteries and provide adequate blood flow within the first hour or so the patient will usually have minimal damage."

SOURCES: Mark, D.B. New England Journal of Medicine, Feb. 19, 2009; manuscript received ahead of print. Daniel B. Mark, MD, MPH, director, Outcomes Research Group, Duke University Medical Center, Durham, N.C. Judith S. Hochman, MD, New York University School of Medicine. George Sopko, MD, MPH, senior cardiologist, National Heart Lung and Blood Institute.

©2009 WebMD, LLC. All Rights Reserved.