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Nov 18, 2003 (United Press International via COMTEX) -- LEAD CAN AFFECT BRAIN DEVELOPMENT
Neuroscientists have shown even low levels of lead can affect the growth and development of embryonic stem cells in the brain. Jay Schneider, professor of neurology, pathology, anatomy and cell biology at Jefferson Medical College of Thomas Jefferson University, says lead exposure has been known to have potentially adverse effects on children's cognitive abilities. Such exposure is particularly dangerous to the fetus, he said. In animal tests, Schneider and colleagues found levels of lead lower than those deemed safe for humans by the Centers for Disease Control and Prevention can retard the growth and development of certain neural stem cells. These are cells that can become one of three cell types: a neuron, an oligodendrocyte or an astrocyte. The latter two cell types play supportive roles in the brain. In the experiments, lead was found to curtail the ability of stem cells to develop into either neurons or oligodendrocytes, but increased their ability to become astrocytes, he said. Women exposed to lead as youngsters can, when pregnant, pass the toxin to their unborn children, Schneider said.
ASTHMA HITS BOYS AS CHILDREN, WOMEN AS ADULTS
Nearly 2 out of 3 children with severe asthma are boys, yet women account for more than 2 out of 3 adults with severe asthma. The reasons remain unexplained, says Dr. Joseph Spahn of the National Jewish Medical and Research Center. He also reports in an article in the journal Chest his study of 275 patients showed children with severe asthma had surprisingly good airflow in and out of their lungs. This could lead to misdiagnosis and undertreatment, he said. "Our findings highlight many of the significant differences between severe asthma in children and adults," Spahn said. "We hope they will spur further research that can lead to a better understanding and better treatment of this disease."
MISCONCEPTION KEEPS PATIENTS FROM SURGERY
The widely held misconception that its exposure to air will cause lung cancer to spread may be keeping patients from undergoing needed surgery, doctors say. They say nearly 40 percent of patients have such a perception, which has no basis in scientific fact. "This belief is very prevalent, especially among African-Americans, and it may be used by many to avoid recommended surgical intervention," noted Dr. Mitchell Margolis, director of the pulmonary clinic at the Philadelphia Veterans Affairs Medical Center and lead author of the study published in the Annals of Internal Medicine. "Our findings may be helpful in suggesting appropriate action by physicians to address this belief."
DIETING MAY PROMOTE WEIGHT GAIN IN CHILDREN
Research indicates dieting to shed pounds may in fact produce the opposite effects in children. Studies show 30 percent of girls and 16 percent of boys try to limit their food intake to lose weight. Scientists at Brigham and Women's Hospital report in the journal Pediatrics frequent dieting among children ages 9 to 14 was not only ineffective but also appeared to result in weight gain long term. "Our nationwide study found that as many as 1 in 4 American children under the age of 14 were dieting," said researcher Alison Field. The prevalence of overweight and obese children has increased by 100 percent since the 1980s, she noted. Americans spend about $33 billion a year on weight loss products and services, but only about 1 in 5 adults follow recommended diet guidelines, possibly explaining why most people fail to take pounds off permanently. It now appears dieting may be equally unsuccessful in children, the scientists said.
(Editors: For more information about LEAD, contact Steve Benowitz at (215) 955-6300 or steven.benowitz@jefferson.edu. For ASTHMA, William Allstetter at (303) 398-1002 or allstetterw@njc.org. For SURGERY, James Blue at (212) 807-3424 or james.blue@mail.va.gov. For DIETING, Amy Dayton at (617) 534-1600)
Copyright 2003 by United Press International.