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Biomedical subjects

R Dennis

Publications and source records attributed to R Dennis.

8 recordsLinked to original sources

Insect glial cells show differential expression of a glycolipid-derived, glucuronic acid-containing epitope throughout neurogenesis: detection during postembryogenesis and regeneration in the central nervous system of Tenebrio molitor L.

The monoclonal antibody CAF-1 recognises a glucuronic acid-containing epitope present on insect acidic glycolipids. Immunohistochemical analysis of the CAF-1 epitope has revealed its differential, temporal and spatial expression during postembryogenesis of the midbrain of Tenebrio molitor. Electron microscopic resolution demonstrated, that the CAF-1 epitope is expressed on glial cells that ensheath the glomeruli of the central body. Concomitantly, a differential pattern of expression was observed in the ventral nerve cord, exhibiting a serially homologous display on glial cells that ensheath neuronal somata in the cell body layer of the thoracic ganglia and ventral associative neuropil. Prominent, topologically restricted CAF-1 immunoreactivity was monitored in termination areas of sensory neurons in the ventral associative neuropil and corresponding nerves 6-48 h after extirpation of the respective sensory neuron somata. CAF-1 expression is correlated with structural reorganisation in postembryonic nervous tissue of T. molitor.

Animals

Demonstration of an ecdysteroid receptor in a cultured cell line of Drosophila melanogaster.

Incubation of the high-speed supernatant from the Kc cell line of Drosophila melanogaster with [3H]ponasterone A results in significant binding of the ligand as determined by gel filtration and dextran-coated charcoal binding assays. In vivo exposure of the Kc line to [3H]ponasterone A for 30 min results in a marked binding of the ligand by a KCl-soluble nuclear extract. With both the cytosol and nuclear preparations the binding has specificity and a low dissociation constant (3 X 10(-9) M). In addition the labeling of the nuclear preparation exhibits a saturation at approximately 7 X 10(-10) M which probably reflects the molar concentration of cytoplasmic receptors.

Binding, Competitive

Evidence of respiratory tract infection induced by equine herpesvirus, type 2, in the horse.

Five horses were experimentally exposed to equine herpesvirus 2 strain LK. Two young foals developed chronic pharyngitis (98 and 232 days, respectively). Growth characteristics, cytopathic effects (CPE), inclusion body formation, ether sensitivity, and immunofluorescent analysis indicated that the virus recovered from infected animals was a herpesvirus serologically identical with, or at least antigenically related to EHV-2 strain LK. No significant complement-fixing (CF) or virus-neutralizing (VN) antibody responses were observed in adult horses while both foals demonstrated a rise in CF antibody titer. One of the two foals demonstrated a rise in VN antibody only. The results suggest that EHV-2 virus induced chronic pharyngitis, primarily the result of lymphoid proliferation, with no overt clinical signs.

Animals

On the decrease in the life expentancy of black males in Michigan.

The 1970 census reported that there were slightly more than 1 million nonwhites among Michigan's 8,875,000 residents. Ninety-five percent of these nonwhites are black, and 75 percent live within the city limits of Detroit, compared with 10 percent of the State's white residents. Between 1959-61 and 1969-71, life expectancy at birth increased about 1 year for black and white females, essentially remained unchanged for white males, and decreased more than 3 years for black males. In 1969-71, life expectancy was 61 years for black males, 68 years for white males, 69 years for black females, and 75 years for white females. Much of this growing disparity noted resulted from a dramatic rise in deaths of black males in the 15-44 year age group. Two-thirds of this increase was caused by a major rise in mortality from two causes--accidents and homicides. While death rates for black males decreased for a number of other leading causes, these generally remained higher than similar figures for each of the other three race-sex groups. Given current rates, one of eight black males in Michigan ultimately will die from an accident or from homicide. This probability is 1 of 17 for white males, 1 of 30 for white females, and 1 of 26 for nonwhite females. Homicides reduced the life expectancy of black males by 2.3 years, compared with 0.2 year for white males, less than 0.005 year for white females, and 0.5 year for black females. More than three-quarters of all homicides of black males in Michigan in 1973 were caused by handguns.

Accidents