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Biomedical subjects

T Gibson

Publications and source records attributed to T Gibson.

At least 145 records · Page 8Linked to original sources
PubMed1983

Methylthioadenosine phosphorylase activity in human erythrocytes.

An enzyme capable of degrading 5'-methylthioadenosine to adenine was found in the human erythrocyte. A rapid assay for this enzyme, 5'-methylthioadenosine phosphorylase, was developed using high pressure liquid chromatography. The specific activity in 24 normal subjects was 8.9 +/- 2.0 nmol . mg-1 Hb . h-1. Levels within this range were also found in erythrocyte lysates from gouty subjects and patients with a variety of inborn errors of purine metabolism, including patients with a complete deficiency of the adenine salvage enzyme--adenine phosphoribosyltransferase. Erythrocyte lysates from the latter however, were unable to convert the adenine produced to AMP in a linked assay system, in contrast to controls and other patients. These results support the suggestion that adenine, which is excreted in quantity by patients with adenine phosphoribosyltransferase deficiency is derived endogenously from 5'-methylthioadenosine as a by-product of polyamine biosynthesis.

Adenine↗
PubMed1983

A comparison of conventional and low dose sodium aurothiomalate treatment in rheumatoid arthritis.

Forty-one patients were given sodium aurothiomalate either in the conventional dose of 50 mg weekly for five months or in a small dose of 10 mg weekly for the same period. Monthly maintenance injections of 50 mg and 20 mg, respectively, were continued for a further seven months. A high incidence of toxicity and the subsequent withdrawal of 15 patients from the study prevented any analysis of results beyond five months. Statistically significant clinical improvements occurred with both treatment regimes. Although there were no significant differences between the clinical measurements of the treatment groups at any stage, a significant reduction of ESR and serum IgM occurred only with the higher dose. Side-effects were more frequent and occurred earlier with conventional treatment. However, severe toxicity, demanding withdrawal from the study, was slightly more common in the low-dose group. Thus, at least in the short term, conventional- and low-dose regimes appeared equally effective. A small dose did not lesson the hazards of toxicity.

Arthritis, Rheumatoid↗
PubMed1983

Cyclofenil treatment of scleroderma--a controlled study.

A double-blind cross-over study of cyclofenil and placebo treatments was conducted in 11 scleroderma patients. Each treatment period was for four months. A range of subjective and objective measurements failed to reveal any consistent or obvious response to cyclofenil. One patient died of his disease during active treatment. Four were withdrawn because of liver dysfunction which was attributed to cyclofenil. It remains to be seen whether treatment over longer periods will exert a clinically significant effect.

Adult↗
PubMed1983

A controlled study of diet in patients with gout.

To determine whether patients with gout have a diet which is distinctive in quality or quantity a careful dietary questionnaire was posed over 7 days to 61 men with gout and 52 control subjects. The average daily intake of most nutrients, including total purine nitrogen, was similar except that the patients with gout drank significantly more alcohol. Beer was the most popular beverage, and 25 (41%) of those with gout consumed more than 60 g alcohol daily (equivalent to 2 . 5 litres of beer). The heavy drinkers had a significantly higher intake of purine nitrogen, half of which was derived from beer. Though the effect of ingested purine on the blood uric acid is difficult to estimate, it probably was sufficient to have a clinical effect, augmenting the hyperuricaemic effect of alcohol itself.

Alcoholic Beverages↗
PubMed1982

World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guidelines for evaluating the efficacy of anthelmintics in ruminants (bovine and ovine).

During the 8th International Conference of the World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) held in Sydney, Australia, in 1977, President S. Gaafr appointed a committee to prepare international guidelines for evaluating the efficacy of anthelmintic products. The goal was to develop uniform testing standards and registration requirements to expedite the testing and approval of effective products with a minimum of labor, money, and experimental animals without sacrificing scientific validity. Achievement of such a goal would mean that data from investigators in one country could be used in registering drugs in another country. These guidelines, which were approved by the membership at the general meeting of the 9th International Conference of the W.A.A.V.P. on July 16, 1982 in Budapest, Hungary, are only a beginning in the development of uniform international methods for testing the efficacy of anthelmintics. We now propose that they be used by the scientific community recognizing that, at this time, these guidelines have not been officially reviewed or accepted by any government regulatory authority. Investigators are encouraged to evaluate this document critically and to recommend modifications promptly to the Committee so that they may be incorporated in these guidelines before the 10th International Conference to be held in Perth, Australia in 1983.

Animals↗
PubMed1982

Allopurinol treatment and its effect on renal function in gout: a controlled study.

Fifty-nine patients with primary gout were treated with either a combination of colchicine and allopurinol or colchicine alone. Assessments of renal function over 2 years revealed a statistically significant fall of glomerular filtration rate an urine concentrating ability in those receiving only colchicine. The renal function of patients given allopurinol did not change. Treatment with allopurinol resulted ina significant reduction of ammonium excretion, a phenomenon which could not be readily explained. Urate clearance also declined during allopurinol treatment, and the impaired urate clearance associated with gout became more evident. The most important observation was that allopurinol retarded an apparent decline of renal function. Presumably this was achieved through its hypouricaemic effect and implies that the hyperuricaemia of gouty patients is deleterious to the kidneys.

Adult↗
PubMed1982

Scleroderma and erosive polyarthritis: a disease entity?

We describe 4 patients with scleroderma in whom a major clinical feature was a deforming, erosive polyarthritis accompanied by positive tests for rheumatoid factor. In all but 1 case the skin involvement preceded joint symptoms, and in some cases there was evidence of systemic involvement. This destructive arthritis may represent the coexistence of 2 diseases or an extreme form of the inflammatory arthritis seen in scleroderma. Alternatively, the clinical presentation may represent an 'overlap syndrome' with features of both scleroderma and rheumatoid arthritis.

Aged↗
PubMed1982

Lymphocyte studies in rheumatoid arthritis. V. Suppressor cell function in peripheral blood.

Peripheral blood lymphocytes from 30 patients with rheumatoid arthritis and 14 controls were examined for suppressor activity by two different assays. These were the Concanavalin-A-induced and the short-lived suppressor cell assays. There was no difference in suppressor activity between patients and controls, the suppressor activity of HLA-DR3 positive patients was no less than that of non-DR3 patients. However, patients with nodules showed reduced suppression in the short-lived suppressor cell assay when compared with patients without nodules.

Adult↗
PubMed1981

Familial gout and renal failure.

Clinical gout and renal failure was seen in a 9-year-old girl. The family tree showed that 9 out of 11 young females in three generations suffered from hyperuricaemia and normal (n = 1), or impaired (n = 8), renal function. One set of twins occurred in each generation and there is only one living male subject. In members with renal failure there was no improvement in renal function after treatment of hyperuricaemia, and in 2 sisters oral contraceptives appeared to precipitate hypertension. This clinical picture may be more common than is generally realised because of failure to compare blood uric acid values with suitable age- and sex-matched controls. The evidence from this family suggests that hyperuricaemia preceded the development of renal failure.

Adult↗
PubMed1981

Maintenance chrysotherapy in rheumatoid arthritis: a comparison of 2 dose schedules.

Maintenance treatment with chrysotherapy was given to 44 rheumatoid patients after a total of 1.0 g weekly injections of sodium aurothiomalate. 21 patients continued with 50 mg injections every 2 weeks, and 23 patients received the same dose at 4-week intervals. Their progress was followed over 1 year, after which time their clinical improvements were equally well sustained. Toxicity was greater in those patients receiving fortnightly injections. Five patients suffered a relapse after 8 months. These were not related to the frequency of injections nor to the serum gold levels. There appeared to be no advantage in maintenance injections at fortnightly intervals.

Adult↗
PubMed1981

Changes in immune function in patients with rheumatoid arthritis following treatment with sodium aurothiomalate.

The mitogenic response of peripheral blood lymphocytes from 21 patients with rheumatoid arthritis to concanavalin-A (con--A), phytohaemagglutinin (PHA), and pokeweed mitogen (PWM) was significantly lower than in 30 normal subjects. After 15--24 weeks' treatment with sodium aurothiomalate (GST) the response to these mitogens rose to within the normal range. Improvement over pretreatment values was significant for con-A and PWM measured as area under the dose response curve but only for con--A if response at optimal mitogen concentration is the sole criterion. The improvement in PHA response was not significant with either method of measurement. There was an improvement in disease activity by 15--24 weeks as measured by a fall in serum C-reactive protein (CRP), IgM rheumatoid factor (RF), Clq binding activity (ClqBA), and Ritchie articular index. Con--A lymphocyte responsiveness was inversely related to serum CRP levels, but measurements of disease activity were otherwise unrelated to lymphocyte mitogen responsiveness. The observed improvement in peripheral blood lymphocyte responsiveness during gold treatment contrasts with the suppressive effect of gold in vitro. We suggest that the improvement in lymphocyte function is due to the lessening of rheumatoid disease activity during gold treatment, and that the low serum gold levels in our patients were insufficient to mask this effect. Sera from some of our patients were capable of suppressing the function of normal lymphocytes, and this was less apparent after treatment. The suppressive effect of sera correlated with ClqBA. Suppressive factors in serum, including possibly immune complexes, may be one factor leading to suppression of lymphocyte function during rheumatoid arthritis. Such an inverse relationship between humoral and cellular immune mechanisms might influence the clinical expression of rheumatoid arthritis.

Arthritis, Rheumatoid↗
PubMed1981

Synovial histopathology of behçet's syndrome.

Synovial tissue obtained from 7 patients with Behçet's syndrome and 7 patients with early rheumatoid arthritis could not be distinguished under ordinary light microscopy when examined blind. A wide spectrum of features was seen in both diseases, and it is suggested that these may reflect severity and duration as much as the nature of the arthritis. Electron microscopy also failed to illustrate any distinct features of Behçet's syndrome, but immunofluorescent studies indicated consistent deposition of IgG.

Adult↗