Search PubMed⌕ Search

Biomedical subjects

D J Anderson

Publications and source records attributed to D J Anderson.

At least 433 records · Page 24Linked to original sources
PubMed1982

Immunosuppressive effects of mouse seminal plasma components in vivo and in vitro.

Mouse seminal plasma (SP), a mixture of aqueous extracts of prostate, seminal vesicle, and epididymis, exerts potent immunosuppressive effects in vivo. The SP mixture completely suppressed both primary and secondary humoral immune responses in mice to low immunizing doses of antigen (bovine serum albumin or washed epididymal sperm), and also significantly suppressed the antibody response to high doses of immunizing antigen. The humoral immune response to epididymal sperm was also suppressed when sperm were incubated in SP and then washed before immunization and when SP was administered at a secondary site (i. p.) at the time of sperm immunization (subcutaneous). When SP components were tested individually in in vitro assays, all of them (prostate, seminal vesicle, and epididymis) suppressed mitogen-induced lymphocyte transformation. Prostatic fluid also inhibited complement-mediated hemolysis in a standard immune hemolytic assay. These data indicate that potent immunosuppressive factors are present at several locations within the male reproductive tract; these factors may serve to protect sperm from immunologic damage and prevent sensitization of females to sperm antigens after insemination.

Animals↗
PubMed1981

In vitro synthesis, glycosylation, and membrane insertion of the four subunits of Torpedo acetylcholine receptor.

We have characterized the early biosynthetic forms of the Torpedo electroplax acetylcholine receptor by using a cell-free protein synthesizing system. We obtained primary translation products of approximately 38, 50, 49, and 60 kilodaltons for the alpha, beta, gamma, and delta polypeptides, respectively, by using immunoprecipitation with subunit-specific antisera. These chains could each be labeled by the formylated initiator [35S]Met-tRNA. On cotranslational incubation with pancreatic rough microsomes, glycosylated forms of each subunit were obtained that had molecular weights close to those of their mature authentic counterparts. Extensive trypsinization reduced the glycosylated forms of the receptor subunits to glycosylated membrane-protected fragments of approximately 35 (alpha), 37 (beta), 45 (gamma), and 44 (delta) kilodaltons. In this system, then, each receptor chain spans the membrane at least once. This in vitro-synthesized material apparently exhibited neither oligomeric assembly nor alpha-bungarotoxin binding.

Animals↗
PubMed1980

Designing a better postural measurement system.

For more than a century the phenomenon of postural sway has attracted the attention of neurologists, control engineers, and otoneurologists, because body sway provides a global assessment of the sensorimotor systems involved in postural control. This article presents an overview of the history of body sway studies, highlighting some of the shortcomings of past techniques. Spurred on by these shortcomings, we specified design criteria for a better postural measurement system. The system has been implemented, and some of the preliminary applications are detailed that demonstrate the utility of our approach.

Aged↗
PubMed1979

Electrocochleography and experimentally induced loudness recruitment.

The relationship between changes in loudness and the cochlear whole-nerve potential following experimentally produced deafness was studied in an animal model. Reaction time of a subject's response to an auditory stimulus has been shown to be an index of loudness in human experiments and has been adapted to nonhuman primates. In a series of experiments, four macaque monkeys were operantly conditioned to respond to 8-kHz tones over a range of 3--80 dB SPL, and their reaction times to pure tone stimuli were measured. Whole-nerve cochlear action potentials were recorded from chronic inner-ear electrodes. The relationship between behavioral and electrical measures of loudness recruitment were examined in animals with both temporary and permanent noise-induced hearing loss. Loudness recruitment was demonstrated experimentally after a 1-h exposure to a high-intensity 8-kHz octave band of noise. Excellent agreement was observed between the reaction time function and the action potential input-output function at intervals of 0.5, 12, 24, 48, and 84 h after exposure. Permanent hearing loss was produced in some of these animals by a much longer duration of exposure to the 8-kHz octave band of noise. Recruitment was observed in both the behavioral and the electrical measures. Histological studies of these damaged cochleas revealed primarily outer hair cell destruction, with a relative sparing of inner hair cells and nerve supply. The findings of this study are interpreted as strong support for the clinical electrocochleogram as an objective indicator of the presence of loudness recruitment.

Action Potentials↗
PubMed1979

Delivery of essential services to alcoholics through the "continuum of care".

To provide for the delivery of essential and comprehensive services for alcoholics, a well-developed continuum of care encompasses the following services: an information and referral, or diagnostic, center; detoxification or receiving center; primary rehabilitation; extended rehabilitation; residential intermediate care; outpatient care; a family program; and an after-care program. All of these services are geared toward the ultimate goal of assisting the alcoholic to live independently in the community and to utilize a variety of positive coping devices while remaining abstinent from beverage alcohol.

Aftercare↗