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Biomedical subjects

R Willoughby

Publications and source records attributed to R Willoughby.

24 records · Page 2Linked to original sources
PubMed1982

T-cell function in chronic lymphocytic leukaemia.

Fifteen patients with chronic lymphocytic leukaemia (CLL) were studied. The diagnosis was made by a combination of clinical findings, peripheral blood morphology and cell surface markers. The Rai clinical staging (Rai et al, 1975) was used to classify all patients. Serum immunoglobins, B and T cell lymphocytes, TG and TM cell populations were evaluated in all patients before commencing treatment. No correlation was found between clinical staging and the presence or absence of hypogammaglobulinaemia. The ratios of TG to TM cells were abnormal in all patients and this abnormality paralleled the stage of the disease. While there was significant difference in the proliferative responses of highly purified T cells from patients and controls at 1 micrograms and 2 micrograms/ml of Concanavalin A (Con A) (P values = P less than 0.005 and P less than 0.01 respectively). There was no significant difference at dose 5 micrograms/ml. The ability of T cells to suppress allogeneic PBMC responses to Con A was dependent on T cell purification procedures. The significance of the results and the possible role of T cells in the pathogenesis of CLL is discussed.

Cell Division↗
PubMed1982

Incidence of squamous cell carcinoma in hairless mice irradiated with ultraviolet light in relation to intake of ascorbic acid (vitamin C) and of D, L-alpha-tocopheryl acetate (vitamin E).

We have carried out a study of large malignant skin tumours (squamous-cell carcinomas) and other lesions in "hairless" mice (in groups of 45 or 60 mice) intermittently exposed to ultraviolet light over a period of 15 weeks, beginning when the mice were about 8 weeks old. Various groups were given a standard diet (Wayne Lab-Blox) or the same food with added vitamin C or vitamin E throughout the study. Lesions, classified by histopathologic study as atypical squamous-cell proliferations varying from early actinic keratoses to invasive poorly differentiated squamous-cell carcinomas, had begun to develop by the end of the period of irradiation. They were counted twice a month for five months. The observed fraction of mice that developed lesions during successive time periods was analyzed by the statistical method recommended by a committee of the International Agency for Research on Cancer. A pronounced effect of vitamin C in decreasing the incidence of the malignant lesions was observed with very high statistical significance. No significant effect of vitamin E was observed. We conclude that vitamin C should be given special attention with respect to the relation between diet and cancer.

Animals↗
PubMedDate not supplied

Characterization of genetic markers for in vitro cell line identification of the marine sponge Axinella corrugata.

The marine sponge Axinella corrugata is being developed as a model organism for in vitro marine invertebrate research. Molecular genetics methods such as DNA fingerprinting [amplified fragment length polymorphism (AFLP) and single-stranded conformation polymorphism (SSCP)] and single-locus DNA sequence analyses were applied to this model to meet the primary objective of identifying positive A. corrugata-specific molecular markers that will aid in verifying cell identity in vitro and distinguish sponge cells from potential microbial contaminants. The extent of intra- and interspecific variation in these markers from geographically distinct samples of A. corrugata and closely related sponge taxa was also assessed. Two novel nuclear loci along with intervening transcribed spacer (ITS) regions of nuclear rRNA were characterized, although the latter appeared to better meet primary marker criteria, such as taxonomic specificity and high frequency of detection (via polymerase chain reaction [PCR]) from different individuals (n > 40) and cell cultures. Phylogenetic and phylogeographic analyses of ITS DNA sequences helped clarify taxonomies and also suggested species boundaries between and among western Atlantic and eastern Atlantic/Indian Ocean A. corrugata and Axinellidae samples. Patterns of genetic variation have important implications for the systematics, evolution, and chemical ecology of A. corrugata and related axinellids and are discussed.

Animals↗
PubMedDate not supplied

Partial sleep deprivation reduces natural killer cell activity in humans.

Sleep disturbance, measured by either subjective report or electroencephalographic (EEG) assessment of sleep, correlates with a reduction of natural killer (NK) cell activity in major depression. To test whether sleep loss independent of mood disturbance alters daytime values of cellular immune function, the effect of late-night partial sleep deprivation on NK cell activity was studied in 23 medically and psychiatrically healthy male volunteers. After a night of sleep deprivation between 3 and 7 AM, NK cell activity was reduced in 18 of the 23 subjects with average lytic activity reduced significantly (p < .01) to a level 72% of the mean of three separate baseline values. After a night of resumed nocturnal sleep, NK cell activity had returned to baseline levels. These data implicate sleep in the modulation of natural immunity and demonstrate that even modest disturbances of sleep produce a reduction of NK cell activity.

Adult↗