Category: Ajit Varki
Irvine, Calif. -- Researchers have identified what they believe is the original source of malignant malaria: a parasite found in chimpanzees in equatorial Africa.
Group B Streptococcus (GBS), a bacterial pathogen that causes sepsis and meningitis in newborn infants, is able to shut down immune cell function in order to promote its own survival, according to researchers at the University of California, San Diego School of Medicine and the Skaggs School of Pharmacy and Pharmaceutical Sciences.
Currently available lines of human embryonic stem cells have been contaminated with a non-human molecule that compromises their potential therapeutic use in human subjects, according to research by investigators at the University of California, San Diego (UCSD) School of Medicine and the Salk Institute in La Jolla, California.
In a study published online January 23, 2005 in the journal Nature Medicine, the researchers found that human embryonic stem cells, including those currently approved for study under federal funding in the U.S., contain a non-human, cell-surface sialic acid called N-glycolylneuraminic acid (Neu5Gc), even though human cells are genetically unable to make it. In a related paper published November 29, 2004 by the Journal of Biological Chemistry (JBC), the Varki group has also discovered the exact cellular mechanism by which this occurs.
Genes that control the size and complexity of the brain have undergone much more rapid evolution in humans than in non-human primates or other mammals, according to a new study by Howard Hughes Medical Institute researchers. The accelerated evolution of these genes in the human lineage was apparently driven by strong selection. In the ancestors of humans, having bigger and more complex brains appears to have carried a particularly large advantage, much more so than for other mammals.
A non-human, cellular molecule is absorbed into human tissues as a result of eating red meat and milk products, according to a study by researchers at the University of California, San Diego (UCSD) School of Medicine, published online the week of September 29, 2003 in Proceedings of the National Academy of Sciences. The researchers also showed that the same foreign molecule generates an immune response that could potentially lead to inflammation in human tissues.