A scientist at the Marine Biological Laboratory (MBL) has published the results of an EPA-funded clam embryo study that supports her hypothesis that, when combined, the pollutants bromoform, chloroform, and tetrachloroethylene--a chemical cocktail known as BCE--can act synergistically to alter a key regulator in nerve cell development. While scientists have previously studied the effects of these pollutants individually, this is the first time anyone has demonstrated that BCE's components can work together to adversely affect neuron growth in a model organism. The study, which is reported in the January 2005 issue of Environmental Toxicology and Pharmacology, is the first step toward understanding how exposure to BCE might affect human nerve cell development--knowledge that may one day provide clues about such neurological mysteries as autism spectrum disorder or attention deficit hyperactivity disorder.

The best method for preventing HIV patients from developing drug resistance is a careful, dedicated adherence to their prescribed drug regimen, according to a long-term, large-scale study presented today in New York City at the American Medical Association Media Briefing, HIV/AIDS, The Drug Resistance Epidemic. Other key predictors of resistance include measures of how much virus was present in a person's bloodstream at the start of therapy and how much their immune status was compromised.

A recently developed mouse model of brain tumors common in the genetic disorder neurofibromatosis 1 (NF1) successfully mimics the human condition and provides unique insight into tumor development, diagnosis and treatment, according to researchers at Washington University School of Medicine in St. Louis. After validating their animal model, the team made two important discoveries: New blood vessels and immune system cells may be essential to the initial formation of tumors and therefore may be promising drug targets; and brain images often used to determine the need for treatment may not actually be diagnostically informative.

B cell chronic lymphocytic leukemia (B-CLL) is the most common leukemia in adults and is characterized by the progressive accumulation of mature B lymphocytes in the blood, bone marrow, and lymphatic tissues. It is believed that in the early stages of disease, B-CLL is the result of an undefined defect in the programmed signals that trigger normal B cell death (apoptosis). Livio Trentin and colleagues from Padua University School of Medicine now demonstrate that high levels of expression and altered cellular location of an enzyme in B cells known as Lyn, contributes to the development of B-CLL.

In a project that already has benefited an important field of biomedical research, scientists have deciphered the genomes of two closely related strains of Cryptococcus neoformans, a fungus whose importance as a human pathogen has risen in parallel with the HIV/AIDS worldwide epidemic and the increased use of immunosuppressive therapies. The study, posted online January 13 in Science Express, revealed differences in the virulence strategies used by C. neoformans compared to other pathogenic fungi. Researchers also examined the genetic determinants of its pathogenicity by comparing the genomes of two closely related strains of significantly different virulence.

By impaling individual chromosomes with glass needles one thousandth the diameter of a human hair, a Duke University graduate student has tested their "stickiness" to one another during cell division. Her uncanny surgical skills have added a piece to the large and intricate puzzle of how one cell divides into two -- a process fundamental to all organisms. In the Dec. 14, 2004, issue of Current Biology, Leocadia Paliulis and Bruce Nicklas report their progress in understanding how the pairs of chromosomes in each cell manage to balance their adhesion to one another and their release during cell division. Their work was sponsored by the National Institutes of Health. Chromosomes are the tiny fiber structures in the cell that house its genes. They replicate and separate in the process of cell division.