Medi watch

PUBLISHED : Monday, 17 December, 2007, 12:00am
UPDATED : Monday, 17 December, 2007, 12:00am

Body clock switch pinpointed

The chemical switch that activates the genetic mechanism regulating the body's internal clock has been identified. The discovery, by University of California researchers, paves the way for new drugs to treat sleep disorders and related problems. 'Because the triggering action is so specific, it appears to be a perfect target for compounds that could regulate this activity,' says study author Paolo Sassone-Corsi in Nature magazine. The research pinpoints a single amino acid that triggers the genes that regulate circadian rhythms. Because of the complex genes involved, the researchers say they're surprised to find that a single amino acid switches on the body clock mechanism, HealthDay reports.

Risks of early elective C-section

Babies born by elective C-section before the 39th week of pregnancy have a three- to four-fold higher risk of breathing trouble than babies born in a normal vaginal delivery, say researchers at Denmark's Aarhus University Hospital. Data analysis on 34,458 babies born in Aarhus, Denmark, from 1998 to 2006 showed nearly 2,700 of the infants were delivered via elective C-section. The researchers compared these infants to infants from women who tried to have a vaginal delivery, including women who ended up having a C-section, WebMD reports. After adjusting for factors that might affect breathing, they found that babies delivered by elective C-section at 37 weeks' gestation had a 3.7-fold higher risk - and at 38 weeks, a 3-fold higher risk - of transitory tachypnea (wet lung), respiratory distress syndrome or persistent pulmonary hypertension (high blood pressure in the lungs).

Newborns benefit from vitamin A

Vitamin A supplements given in the early newborn period can reduce the risk of infant deaths from diarrhoea, fever and respiratory infections, but doesn't reduce the occurrence of these problems. These were the findings of a trial in Madurai, South India, by researchers from Johns Hopkins University in Baltimore, who published their results in the Journal of Nutrition. Vitamin A supplements were randomly assigned to 5,786 babies within 48 hours of birth and 5833 newborns were given inactive placebos, Reuters reports. Death rates due to diarrhoeal diseases and fever were markedly lower among vitamin A-treated infants compared with those given the placebo.

Cholesterol levels healthy in US

Americans may be too fat, but at least their cholesterol is low. A national study by the US Centres for Disease Control and Prevention has found that, for the first time in nearly 50 years, the average cholesterol level for US adults is in the ideal range. Assessments that included blood tests found the total average cholesterol level dropped to 199 last year - 200 and lower is considered ideal. The improvement is put down to the growing use of cholesterol-lowering pills in middle-aged and older people, AP reports. When the survey began in 1960, the average cholesterol was at 222. The new results are based on a national sample of about 4,500 people age 20 and older from 2005-06.