Friday, December 15, 2006

Health Headlines - December 15

Unfertilized Mouse Eggs Produce Stem Cells

U.S. scientists have found a way to get stem cells from unfertilized mouse eggs, but still need to solve several problems before they try the method on human eggs, the Associated Press reported.

If it is successful in humans, this approach isn't likely to raise the same kinds of ethical concerns surrounding current stem cell production, which requires a fertilized embryo that's killed as stem cells are harvested.

The research with mouse eggs, led by Dr. George Q. Daley of the Children's Hospital of Boston, involved a procedure (parthenogenesis) that uses a series of chemical treatments to prompt an unfertilized egg to begin embryonic development, the AP reported.

The study was published online Thursday by the journal Science.

Stem cells, which can grow into many kinds of tissue, hold promise for treating many kinds of diseases and injuries.


Proteins May Help Predict Toxoplasmosis Threat: Study

Two proteins that enable the common parasite Toxoplasma gondii to thrive and that could help predict when it can be deadly have been identified by Stanford University School of Medicine researchers.

T. gondii infects hundreds of species of warm-blooded animals and is present in about 50 percent of humans. Most of the time, it causes no symptoms. But it can cause severe infections in people with weakened immune systems and birth defects in fetuses of women infected with the parasite.

In mice, the Stanford researchers identified two proteins that the parasite introduces into the cells of hosts it infects. The researchers also found that certain changes in either of the proteins (called kinases) increased by 10,000-fold the harm that the parasite caused in the mice.

The findings, published in the Dec. 15 issue of the journal Science, have implications for treating people infected with toxoplasmosis.


Pain Cells Linked to Type 1 Diabetes

Irregularities in pain-related nerve endings in insulin-producing pancreatic cells may play a role in the development of type 1 diabetes, says a Canadian study in this week's issue of Cell.

The finding could lead to new ways of treating and even preventing the disease, said the researchers at Toronto's Hospital for Sick Children and the University of Calgary.

Most type 1 diabetes research has looked at the immune system as the major cause of the disease. But this study of mice that are prone to diabetes identified a control circuit between insulin-producing pancreatic cells and their associated pain nerves, the Canadian Press reported.

Removing these nerve cells prevented the destruction of cells that produce insulin. Most of the mice did not develop diabetes after these nerve cells were removed, the study said.

The researchers plan to conduct studies of people with a family history of diabetes in order to determine if they have abnormal pain sensitivity that may be associated with the onset of diabetes, the CP reported.


FDA Issuing Fewer Warnings About Drug Ads: Report

In recent years, the U.S. Food and Drug Administration has issued fewer warnings to drug companies for false and misleading direct-to-consumer advertising and is taking longer to act on such infractions, says a Government Accountability Office (GAO) report released Thursday.

Between 1997 and 2001, the FDA took an average of two weeks to issue warning letters to drug companies about ads that violate federal rules. Between 2002 and 2005, it took an average of four months to issue such letters, the report said.

The GAO also found that the number of warning letters issued by the FDA fell by about half between those two time periods, the Associated Press reported.

According to the GAO report, the FDA also does not have an effective method of screening, reviewing and tracking drug ads and Web sites.

The FDA has only six reviewers who are unable to check everything, so they focus on ads with the greatest potential to affect public health, said the U.S. Health and Human Services Department, the FDA's parent agency.

In a letter to be sent Thursday, Sen. Herb Kohl (D-Wisc.) asks the Whit e House to provide the FDA with more money to review and regulate direct-to-consumer drug advertising, the AP reported.


Neural Stem Cells Repair Brain Damage in Mice

Research in mice suggests that neural stem cells may be more effective in repairing damaged brain tissue than previously believed, a finding that could lead to new treatments for stroke and other brain trauma in humans.

University of California, San Francisco researchers found that neural stem cells from the brain's subventricular zone quickly repaired damaged cerebral tissue in newborn mice, Agence France Presse reported.

The study appears in the journal Cell.

"The results were very surprising," research team member Chay Kuo told AFP. "If we can figure out how this happens, and determine that it occurs in human neural stem cells, we may be able to increase the effect and harness it for therapeutic uses."

It took just six weeks for neural stem cells to make repairs in newborn mice whose brains were intentionally damaged by the loss of certain proteins.


More Young U.S. Kids Need Flu Vaccine: Report

More needs to be done to boost the number of U.S. children aged 6 months to 23 months who should be fully vaccinated against influenza, says a report in the new Morbidity and Mortality Weekly Report, published by the Centers for Disease Control and Prevention.

Beginning with the 2004-05 influenza season, the Advisory Committee on Immunization Practices recommended that all children aged 6-23 months receive flu vaccinations each year. Previously unvaccinated children younger than age 9 need two doses administered at least one month apart to be considered fully vaccinated.

The report authors analyzed 2005-06 flu season data from six immunization information system (IIS) sentinel sites in Arizona, Michigan, Minnesota, Montana, Oregon and the District of Columbia.

They found a wide variation in coverage with one or more doses of flu vaccine, ranging from 6.6 percent to 60.4 percent, for children ages 6-23 months. At four of the six sites, vaccination coverage for this age group did increase from the previous flu season.

However, fewer than 23 percent of children at five of the six sites were fully vaccinated, the report said.

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