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G Armitage

Publications and source records attributed to G Armitage.

10 recordsLinked to original sources
PubMed1991

Defective polymorphonuclear leukocyte formyl peptide receptor(s) in juvenile periodontitis.

Juvenile periodontitis (JP) is a disease characterized by severe gingival infections. PMN from some JP patients exhibit abnormal chemotactic responsiveness when challenged with the synthetic formyl peptide, FMLP. While investigating PMN function in JP, we found a patient in whom abnormal PMN chemotactic responses to FMLP were associated with a defective population of PMN formyl peptide receptor(s) (FPR). JP PMN failed to respond chemotactically when challenged with FMLP, but exhibited normal chemotactic responses upon exposure to purified human C5a. Furthermore, JP PMN were capable of degranulating and generating superoxide anion radicals as well as normal PMN upon exposure to FMLP. Binding studies demonstrated that JP PMN had a diminution in the number of high-affinity FPR. Studies in which FPR was radiolabeled by chemical cross-linking demonstrated that JP PMN FPR exhibited the same molecular weight and N-linked glycosylation as normal PMN FPR. JP PMN FPR, however, was more resistant to papain cleavage than normal PMN FPR. Autoradiograms obtained from 2D-PAGE of normal and JP PMN FPR demonstrated decreased amounts of FPR isoforms in JP PMN.

Adult↗
PubMed1989

Comparison of manual and power toothbrushing, with and without adjunctive oral irrigation, for controlling plaque and gingivitis.

We compared the effects of four oral hygiene methods (manual tooth-brushing, power toothbrushing, manual toothbrushing plus irrigation, and power toothbrushing plus irrigation) on plaque and periodontal disease. These methods were tested both when used alone and when used in conjunction with professional mechanical oral hygiene. 108 subjects were clinically assessed for plaque, stain, gingival inflammation, bleeding to probing, probing depth and attachment loss, and randomly assigned to one of the 4 oral hygiene groups. Subjects were carefully instructed in the use of their assigned method and asked to discontinue all other forms of oral hygiene. After 3-months, subjects returned for re-examination and full-month professional mechanical oral hygiene care. 3 months later, subjects returned for a final oral examination. All subjects kept a diary of use of their assigned method and were called every 2 weeks to monitor discomfort, provide reinforcement and answer questions. Results showed that all the oral hygiene methods were equally effective in reducing plaque and stain accumulation, gingival bleeding, bleeding to probing ratio and the % of pockets 4 mm or deeper. None of the oral hygiene methods was associated with injury to soft or hard tissues.

Adolescent↗
PubMed1988

Oral lesions in rhesus monkeys associated with infection by simian AIDS retrovirus, serotype-I (SRV-1).

Simian acquired immunodeficiency syndrome (SAIDS) is a retrovirus-induced immunodeficiency disease that affects certain nonhuman primates and has many parallels to human AIDS. We examined 72 rhesus monkeys (Macaca mulatta) exposed to SAIDS retrovirus serotype-1 (SRV-1) and 81 healthy control monkeys at the California Primate Research Center to determine the prevalence of oral lesions. At the time of examination, 69 of the 72 monkeys exposed to SRV-1 had serologic and/or virologic evidence of SRV-1 infection. None of the 81 control monkeys had any evidence of infection with SRV-1. Acute necrotizing ulcerative gingivitis (ANUG), oral yeast infections, and noma occurred in 10% (p less than 0.01), 4%, and 1%, respectively, of the study group of 72 animals but were found in none of the control animals. Thus, ANUG occurs rather frequently in rhesus monkeys with evidence of SRV-1 infection. The reproducible immunodeficiency that follows inoculation of SRV-1 in rhesus monkeys promises to be a useful model for studying the pathogenesis of ANUG associated with immunodeficiency.

Acquired Immunodeficiency Syndrome↗
PubMed1984

The relationship between energy expenditure and environmental temperature in congenitally obese and non-obese Zucker rats.

The energy expenditure of normal and congenitally obese adult female Zucker rats has been measured by continuous indirect calorimetry for periods of 3-10 days at ambient temperatures varied from 30 to 5 degrees C. Rectal temperatures were also recorded. Exposure to cold caused no ill-effects in normal or obese rats. The rectal temperatures of obese rats were about 1 degree C lower than those of normal rats. The rectal temperatures of normal rats did not change measurably with ambient temperature; in obese rats rectal temperature rose slightly as ambient temperature fell. In normal and obese rats, energy expenditure showed a smooth, steeply sloping, negative relationship to ambient temperature. Energy expenditure per rat was higher in obese than in normal rats at all temperatures. The two slightly curvilinear regressions were nearly 'parallel', with a separation of about 40 kJ/day per rat at the mid-point. This study therefore does not confirm suggestions that obese Zucker rats suffer from a defect in the level of energy expenditure, or in their capacity to increase it when exposed to cold. It is suggested that in both normal and obese rats the level of energy expenditure was determined by thermoregulatory control. The greater heat production of obese rats may have been a response to their lower core temperature. A steady state in which greater heat production is associated with lower core temperature implies lower insulation between body core and surface. This could be due to greater blood flow.

Animals↗
PubMed1984

Root caries.

Explore the source record for details and available documents.

Dental Caries↗
PubMed1983

The effects of supplementation of the diet with highly palatable foods upon energy balance in the rat.

Full energy balance studies have been performed for 9 weeks on four groups of four adult female rats housed in a continuously running indirect calorimeter; for four weeks two of the groups received highly palatable foods in addition to a standard pelleted diet. A further sixteen groups, of which eight received the palatable foods, provided additional carcass composition data. All practicable precautions were taken to measure energy exchange accurately. Comparison of 'start-to-finish' apparent energy balance with carcass composition changes showed a systematic error of approx. +3% of energy throughput. This was most probably caused by losses of energy in food and excreta, which led to over-estimation of energy intake. Variations among individual balance periods added a standard error of approx. +/- 1%: the source of error here was probably imperfect matching of animals analysed at intermediate stages. The rats offered the palatable foods increased their metabolizable energy (m.e.) intake by 106 kJ/day, 51% of the control groups' intake, in the first week of supplementation. Over the whole 4 weeks of supplementation the increase was 64 kJ/day, or 31%. Withdrawal of the palatable foods led to an immediate fall in intake to about two-thirds of control level, and a return to control level over the next 2-3 weeks. Energy expenditure rose more slowly than intake, reaching a fairly steady level ca. 5 days after introduction of the palatable foods. Expenditure was then ca. 22 kJ/day above control level; an increase of 12% above control expenditure or, allowing for systematic and random errors, 33-37% of the additional m.e. intake. Expenditure returned to control level over the 2 weeks after ceasing supplementation. The experimental groups gained weight at a declining rate throughout the period of supplementation. The gain in live body weight at the end was ca. 32 g, but this comprised a carcass weight gain of 37 g and a loss of 5 g gastrointestinal tract contents. The carcass weight gain comprised 27 g fat (i.e. ca. 70% of the weight gained), 9 g lean tissue and 1 g additional water. The gain of carcass energy was 1100 kJ. There was a small increase in body length, an increase in liver weight, and an increase in the weight of the interscapular brown adipose tissue pad. Regression analysis showed that the increase in the weight of the interscapular brown adipose tissue pad reflected the increase in total body fat.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1982

Chronic lymphocytic leukemia. A review of 745 cases and assessment of clinical staging.

Review of 745 cases of chronic lymphocytic leukemia show that clinical staging by either the Rai or Binet method is very valuable in assessment of patients at the time of diagnosis. There is a marked decrease in survival with advancing stage (19.9 years median survival for Rai Stage 0, and 2.5 years and 2.7 years for Rai Stages 3 and 4, respectively). The definition of anemia as Hb less than 11 g/dl as in the Rai staging method appears to give slightly better discrimination among the stages than the Binet staging procedure. Patients with splenomegaly alone (Binet stage 2), however, form a small but distinct group that should be recognized. These is little to be gained by subdividing further according to size of the lymph nodes.

Adult↗