Health briefs: How aspirin may stem cancer
- July 13, 2013 - 11:38 PM
The use of aspirin and other nonsteroidal anti-inflammatory drugs significantly reduces the risk for cancer, but no one has been able to explain why. Now researchers have found that these drugs slow the accumulation of a type of DNA change called somatic genome abnormalities, or SGAs, that lead to uncontrolled cell growth.
The scientists studied 13 people with Barrett’s esophagus, a condition in which cells in the esophagus become damaged, usually by acid reflux. Sometimes the cells become precancerous, and rarely the problem leads to esophageal cancer. The researchers tracked SGAs with periodic biopsies over an average of almost 12 years. Overall, the use of nonsteroidal anti-inflammatory drugs was associated with a 90 percent reduction in the rate of mutations.
The study, published last month in the journal PLoS Genetics, is very small, said the senior author, Carlo C. Maley, director of the Center for Evolution and Cancer at the University of California, San Francisco. But since most cancers take decades to develop, he added, “if you could just slow it down, you could slow it enough to have people die of something else.”
New York Times
Autism, maternal antibody link
An immune system that ensures survival is one of the earliest gifts from a mother to her child. But sometimes, that gift can be a Trojan horse, sending soldiers that are programmed to attack the body’s own antigens into the fetus, where they interfere with brain development. The result is maternal autoantibody related autism, which may account for as much as 23 percent of the cases of that spectrum of brain disorders.
Now researchers at the University of California, Davis, believe they have found the targets of these maternal autoantibodies, a potential step in the path toward preventive treatment for women contemplating pregnancy.
The researchers also demonstrated that these human autoantibodies can change the social behavior and brain mass of a close primate cousin, the rhesus monkey, in ways that are parallel to autism’s symptoms in humans. Though the effects of these immunoglobulin-G compounds on animal and human brains have become more clear in recent years, why they arise in the first place remains a mystery.
“You’re making antibodies to your own proteins, rather than foreign bodies; it’s when the immune system gets it wrong,” said UC Davis immunologist Judy Van de Water, lead author of one of the studies, published in the journal Translational Psychiatry.
Identifying the targets of these oddly programmed proteins has taken years. But through a complex series of lock-and-key experiments, the team identified seven fetal antigens that were attacked by the maternal autoantibodies. All but one have been linked with the creation and development of neurons, particularly in the hippocampus. That region, associated with memory and learning, has been tied to autism in numerous studies.
The neurological role of one antigen, however, known as LDH, remains somewhat mysterious. Although LDH has been found in rodent fetal brains, where it is associated with cellular metabolism, the autoantibodies that attack it have not been shown to have a direct role in interfering with neurological development, researchers said. Nonetheless, levels of LDH often are used to measure cell damage after exposure to toxins — an intriguing hint, perhaps, of an environmental factor in the rise of autoantibodies, the study suggested.
Los Angeles Times
Delaying clamp of umbilical cord may have benefits
Doctors routinely clamp and sever the umbilical cord less than a minute after an infant’s birth, a practice thought to reduce the risk of maternal hemorrhaging. But a new analysis has found that delaying clamping for at least a minute after birth, which allows more time for blood to move from the placenta, significantly improves iron stores and hemoglobin levels in newborns and does not increase the risks to mothers. Doctors usually clamp the umbilical cord in two locations, then cut it between the clamps. The timing of the procedure has been controversial for years, and the new analysis adds to a substantial body of evidence suggesting that clamping often occurs too quickly after delivery.
New York Times
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