Monday, April 30, 2007

Health Headlines - April 30

Chinese Herbal Compound May Treat Kidney Cysts

A compound derived from a traditional Chinese medicine may reduce the incidence of kidney-destroying cysts in people prone to the illness, researchers report.

A Yale University team led by Dr. Craig Crews tested the compound, called triptolide, in mice bred to have a disease similar to human polycystic kidney disease. Triptolide is found naturally in Lei Gong Teng, a medicinal herb used for centuries in China to fight cancer, inflammation and auto-immune disorders.

In polycystic kidney disease, genetic signals that normally inhibit cell growth are turned off, leading to the proliferation of organ-destroying cysts. Patients often lose one or both kidneys and are forced to wait for transplant or go on dialysis.

In the study, Crews' team found that triptolide prevented cyst formation in mice. "If we were able to slow the rate of cyst formation by even 10 percent a year, compounded annually, patients would not die from this disease," he said in a statement. "A relatively small effect would have an enormous clinical benefit."

The findings were scheduled to be presented Sunday at the Experimental Biology 2007 meeting in Washington, D.C.

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Transplanted Marrow Stem Cells Give Local Stem Cells a Boost

Two new studies suggest that transplanted adult bone marrow stem cells do more than just proliferate on their own. They also enhance the proliferative powers of stem cells naturally residing at the transplant site, researchers say.

The finding, from Dr. Darwin Prockop, director of the Center for Gene Therapy at Tulane University, New Orleans, sheds new light on marrow stem cells, which can be taken from a patient's own bone to repair damaged tissues. Prockop was to present the findings Sunday at the Experimental Biology 2007 meeting in Washington, D.C.

In one study, Pockop's team injected human stem/progenitor cells into the hippocampal region of the brains of immunodeficient mice. And in a second experiment, they infused the stem cells into mice with an illness similar to diabetes. Those cells migrated to the pancreas, which produces insulin.

In both cases, the transplanted marrow stem cells began to proliferate as expected, and they also prompted local stem cells to multiply and differentiate. For example, in the diabetes experiment, the transplanted stem cells boosted the number of insulin-producing cells in the pancreas while repairing microscopic damage to the kidneys.

In a statement, Prockop said the results suggest that autologous (from the patient) marrow stem cell transplant could become a safe, effective treatment for diabetics and for people threatened by kidney failure.

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Mouse Study May Explain Why Alcohol Increases Breast Cancer Risk

U.S. researchers say studies with mice may help to explain the link between alcohol consumption and breast cancer risk.

For the first time, researchers at the University of Mississippi Medical Center used a laboratory mouse model to mimic the development of human alcohol-induced breast cancer.

Drinking even moderate amounts of alcohol is an established risk factor for breast cancer in women. A recent study showed that 60 percent of breast cancers worldwide were attributable to alcohol consumption. But, the biology behind alcohol-induced breast cancer was poorly understood, the study authors said.

Possible causes have included alcohol's impact on estrogen metabolism and response, cell mutation and oxidative damage.

Until the new study, there hadn't been an animal model that faithfully mimicked the characteristics of alcohol-induced breast cancer. So the study authors bioengineered female mice that, at six weeks of age, were fed the equivalent of two drinks per day in humans. Control mice received regular drinking water only.

The researchers found that:

  • moderate alcohol consumption significantly increased the tumor size of breast cancer in mice -- a 1.96-fold increase in tumor weight compared to the control mice;
  • alcohol intake caused a 1.28-fold increase in tumor microvessel density compared to the control group;
  • alcohol intake did not cause significant changes in the body weight of the mice.

The researchers are to present their findings at the American Physiological Society annual meeting, which is being held as part of the Experimental Biology (EB 07) meeting. April 28 through May 2, in Washington, D.C.

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FDA Approves New Treatment for Bleeding Disorder

The U.S. Food and Drug Administration approved on Friday a new therapy to prevent excessive bleeding during and after surgery in certain patients with von Willebrand disease (vWD). The disease is the most common inherited bleeding disorder, affecting about 1 percent of the U.S. population.

Humate-P is the second biological product to be approved for surgery and invasive procedures in patients with vWD who don't respond to the medication desmopressin. The first biological product, Aphanate, was approved by the FDA earlier this year. But, Humate-P is the first product specifically for patients with severe vWD who are undergoing major surgery, the agency said.

"This is an important advance for patients with vWD, including those who are severely affected by the disorder," said Dr. Jesse Goodman, director of FDA's Center for Biologics Evaluation and Research. "Humate-P provides a preventive therapy that can make needed surgery not only possible, but also safer."

Men and women are equally affected by vWD, which is caused by a deficiency or defect in certain plasma proteins critical to blood clotting.

Humate-P is manufactured by CSL Behring GmbH, in Marburg, Germany.

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AMA: Tobacco Makers Spend Too Much on Advertising

Despite a two-year decline in the amount of money tobacco makers spend on marketing and advertising, the American Medical Association says too much is still spent on promoting cigarettes and other forms of smoking.

Spending on marketing and advertising among the five largest U.S. tobacco firms fell to $13.1 billion in 2005 from $14.15 billion in 2004 and $15.15 billion in 2003, the U.S. Federal Trade Commission said in a report issued Thursday.

But anti-smoking advocates said promotional spending was still double the amount spent in 1998, the year the tobacco firms entered into a landmark multi-state settlement, the Associated Press reported.

The AMA added its voice to those who called the amount spent by cigarette makers to promote smoking excessive.

"In 2004 and 2005 alone, the tobacco industry spent an exorbitant $27.7 billion to market their deadly products to the American people," the association said in a statement. "That same money could pay for virtually every smoker in America to receive a full course of nicotine treatment to help them quit."

Noting that the effects of smoking kill some 1,200 Americans daily, the group called for giving the U.S. Food and Drug Administration the authority to "regulate the manufacture, sale, distribution, and marketing of tobacco products."

The U.S. Congress is considering legislation giving the FDA such authority, the AP reported. The bill may have a better chance of passing than similar legislation proposed in 2004, the wire service said, since Democrats now control both chambers of Congress.

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