Microbiology

Scientists at the University of Liverpool have found that field mice have evolved a unique way of ensuring faster fertilization, a phenomenon which could explain some cases of infertility in humans. The team, in collaboration with Charles University, Prague, found that field mice sacrifice some of their immunity protection in favor of a more rapid fertilization process. This occurs due to the absence of a protein, called CD46. Present in both animals and humans, it helps protect the body’s cells from attack by its immune system. Over time, field mice have lost the ability to produce this…

Tissue damage triggers an inflammatory response by white cells to protect skin from infection by killing microbes. The same white cells guide the production of layers of collagen. These layers of collagen help the wound heal but they stand out from the surrounding skin and result in scarring. New research from the University of Bristol shows that by suppressing one of the genes that normally switches on in wound cells, wounds can heal faster and reduce scarring. This has major implications not just for wound victims but also for people who suffer organ tissue damage through illness or…

Using embryonic stem cells from mice, UT Southwestern Medical Center researchers have prompted the growth of healthy – and more importantly, functioning – muscle cells in mice afflicted with a human model of Duchenne muscular dystrophy. The study represents the first time transplanted embryonic stem cells have been shown to restore function to defective muscles in a model of muscular dystrophy. The researchers’ newly developed technique, which involves stringent sorting to preserve all stem cells destined to become muscle, avoids the risk of tumor formation while improving the overall muscle…

Entamoeba histolytica, which causes inflammation of the colon (colitis), plays dirty. It attacks and kills human immune cells in seconds. Then the parasite hides the evidence by eating the cells’ corpses. While doing so, it kills nearly 100,000 people each year. Researchers from the University of Virginia and the University of Vermont have discovered a means of inhibiting this most voracious of parasites. The study targets a protein which aids the parasite in its ingestion of immune cell corpses. The research team, led by Dr. William Petri, hypothesized that identifying molecules involved in…

University of California, Irvine researchers have identified a gene that is specifically responsible for generating the cerebral cortex, a finding that could lead to stem cell therapies to treat brain injuries and diseases such as stroke and Alzheimer’s. Dr. Edwin Monuki, doctoral student Karla Hirokawa and their colleagues in the departments of Pathology & Laboratory Medicine and Developmental & Cell Biology found that a gene called Lhx2 serves as the long-sought cortical “creator” gene that instructs stem cells in the developing brain to form the cerebral cortex. This portion of the…

Most chromosomal abnormalities are inherited but researchers writing in the American Journal of Human Genetics found that seven percent of children with autism carry structural changes in the genome that are not found in their parents. The rate of such de novo changes in the general population is typically less than one percent. Structural variants in the chromosomes were found to influence ASD with sufficiently high frequency to suggest that genomic analyses be considered in routine clinical workup, according to the researchers. “Historical studies in identical twins and their families have…

One of the most common human parasites, Toxoplasma gondii, uses a hormone lifted from the plant world to decide when to increase its numbers and when to remain dormant, researchers at Washington University School of Medicine in St. Louis have found. The scientists report this week in Nature that they successfully blocked production of the molecule, known as abscisic acid (ABA), with a plant herbicide. Low doses of the herbicide prevented fatal T. gondii infection in mice. "As a target for drug development, this pathway is very attractive for several reasons," says author L. David Sibley, Ph.D…

When nerve damage occurs, there are a few treatment options; microsurgery to sew two ends of the nerve together, using a nerve from another part of the body to replace a damaged section, or placing an empty tube between the cut ends so that nerve fibers can grow through it and back into the muscle. Grafting a nerve from another part of the body is usually the most effective option, but it creates another injury site and isn’t possible in all patients. The tubes, known as nerve guidance conduits, cannot be used in gaps longer than three or four centimeters. In addition, nerve regeneration…

Fungi don't exactly come in boy and girl varieties, but they do have sex differences. In fact, a new finding from Duke University Medical Center shows that some of the earliest evolved forms of fungus contain clues to how the sexes evolved in higher animals, including that distant cousin of fungus, the human. A team lead by Joseph Heitman, M.D. has isolated sex-determining genes from one of the oldest known types of fungi, Phycomyces blakesleeanus, findings which appear in the Jan. 10 issue of Nature. Fungi do not have entire sex chromosomes, like the familiar X and Y chromosomes that…

Researchers at UT Southwestern Medical Center are uncovering how brain cells are affected in Fragile X syndrome, the most common cause of inherited mental retardation and the most common genetic cause of autism. “I think we’ve discovered a core mechanism underlying Fragile X syndrome," said Dr. Kimberly Huber, assistant professor of neuroscience and senior author of a study appearing in Wednesday’s edition of the Journal of Neuroscience. Dr. Huber’s research with mice focuses on how Fragile X syndrome affects communication between cells in the hippocampus, a region of the brain that is…