Science News

NEWLY IDENTIFIED ROLE FOR ‘POWER PLANTS’ IN HUMAN CELLS COULD LEAD TO TARGETED THERAPIES

COLUMBUS, Ohio – Scientists have determined that human cells are able to shift important gene products into their own mitochondria, considered the power plants of cells. The finding could eventually lead to therapies for dozens of diseases.

The gene products, known as tRNAs, assemble amino acids for the production of proteins within mitochondria. If the mitochondrial tRNA genes are defective or missing, and proteins are not manufactured, the mitochondria are unable to generate adequate energy.

Defective tRNAs are believed to be the cause of about 60 percent of conditions traced to malfunctions in the mitochondria. The range of related conditions includes diabetes, hearing loss and a number of neurological disorders, depending on which kinds of cells are affected….


New study identifies occupations with highest suicide mortality

Suicide mortality in England and Wales is highest in skilled trades and elementary occupations, which include agricultural workers, construction workers, and plant and machine operators, a new study has found.

A higher proportion of deaths due to suicide was also recorded among health professionals compared to the population as a whole.

Published in the July 2008 issue of the British Journal of Psychiatry, the study used mortality data collected by the Office for National Statistics to examine suicide by occupation between 2001 and 2005. Howard Meltzer, Professor of Mental Health and Disability in the Department of Health Sciences, University of Leicester, was one of the authors of the study.

Among men, skilled trades and elementary occupations have the highest suicide mortality, with construction trades, agricultural trades, elementary construction and elementary process plant occupations contributing most to this result. This is consistent with previous Social Class studies of suicide, which show suicide risk to be higher in manual workers. Among women, those with any occupation have lower suicide mortality than those who do not have an occupation, suggesting a protective effect of employment.


MENDEL DIDN’T HAVE THE WHOLE PICTURE: OUR GENOME CHANGES OVER LIFETIME, JOHNS HOPKINS EXPERTS SAY

Contrary to conventional wisdom, it appears that while the overall health of our genomes is indeed inherited from our parents, chemical marks on our genomes’ DNA sequences actually change as we age, driving increased risk of disease susceptibility for us and similarly for our close family members.

Summarizing results of an international collaborative research project, Andrew Feinberg, M.D., M.P.H., concluded that “we’re beginning to see that changes wrought by these epigenetic marks may help explain why susceptibility to many diseases such as diabetes and cancer increases with age.”

Feinberg, a professor of molecular biology and genetics and director of the Epigenetics Center at the Johns Hopkins School of Medicine, added that they may also explain why diseases such as diabetes and cancer, in which we know the environment is important, might arise in part because the environment changes the genes themselves. “In this sense, epigenetics probably stands at the center of modern medicine because unlike our DNA sequences, which are the same in every cell, epigenetic changes can occur as a result of dietary and other environmental exposure,” he said….


Bird watchers, space technology come together in new MSU study

BOZEMAN — Almost every June for 30 years, Terry McEneaney drove around Yellowstone National Park and listed every bird he heard along three routes.

Park ornithologist at the time, he would drive to a designated spot and identify the birds there. Then he’d drive another half mile, repeat the process and continue until he had stopped 50 times in 24.5 miles for the North American Breeding Bird Survey. Trying to finish before the birds quit singing, he’d ignore the scenery as best he could and try not to let the traffic bother him.

“You have to start very early and have to be done about 9:30. Birds stop singing about 9:30,” McEneaney said. “You have to really hustle from point to point.”

McEneaney no longer works for the National Park Service. He retired in November. But the information he gathered is part of a new Montana State University study that looks at biodiversity across North America. Thousands of bird watchers and a satellite sensor developed at the University of Montana yielded data for the continental study….

Comments

  1. #1 Virgil Samms
    June 28, 2008

    The story about mitochondrial import of tRNA spurs many interesting thoughts. Mitochondria have subtle variations in their genetic code, compared to the nuclear genome. Mitochondria are thought to have arisen through endosymbiosis. Many mitochondrial proteins are encoded in the nucleus, and imported to the mitochondria. Horizontal gene transfer only makes sense to the degree that the sharer and sharee have the same genetic code.

  2. #2 sailor
    June 28, 2008

    Suicide was high among Doctors back when I was a student (don’t ask how long, but a very long time ago). One probable reason for high suicide rates among health professionals is that they have easy access to drugs and understand dosage. (Throwing yourself in front of train is takes a lot more work than downing a pill, so you may be more likely to think twice)
    This is easily testable. See how health pofessionals commit suicide compared with other groups. If there is no difference in the kind of method I am wrong.

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