Biomedical subjects

S Gates

Publications and source records attributed to S Gates.

27 records · Page 2Linked to original sources

PubMed1986

Abnormal calcium metabolism caused by increased circulating 1,25-dihydroxyvitamin D in a patient with rheumatoid arthritis.

A 35-year-old white male with rheumatoid arthritis who had developed hypercalcemia, hypercalciuria, and nephrolithiasis was found to be abnormally sensitive to vitamin D as a result of lack of regulation of circulating 1,25-dihydroxyvitamin D (1,25-(OH)2D). An increase in daily intake of vitamin D from 10 micrograms (400 units) per day to 50 micrograms (2000 units) per day produced an abnormal elevation in serum 1,25-(OH)2D, hypercalcemia, and hypercalciuria which were corrected by prednisone. Serum 25-hydroxyvitamin D initially was abnormally low, and increased with vitamin D to values which were in the low normal range. There were significant positive correlations between serum 1,25-(OH)2D (p less than .05) and serum calcium and between serum 1,25-(OH)2D and urinary calcium (p less than .05). Serum immunoreactive parathyroid hormone, initially in the lower range of normal, decreased further during hypercalcemia. A radiograph of the chest, gallium scan, and serum angiotensin-converting enzyme activity were normal. No granulomas or evidence of lymphoma were found in biopsies of the liver and of several lymph nodes. It is concluded that the abnormal calcium metabolism in this patient resulted from increased circulating 1,25-(OH)2D and that the defect in vitamin D metabolism was not related to sarcoidosis, other granulomatous disease, Hodgkin's disease, or lymphoma. The relationship, if any, of the abnormal metabolism of vitamin D and calcium to rheumatoid arthritis remains to be established.

Adult↗

PubMed1983

Effects of methylprednisolone on resolution of acid-aspiration pneumonitis.

We studied the effects of methylprednisolone sodium succinate on the pulmonary function of unanesthetized dogs for four days after aspiration of 1.5 to 2.0 mL/kg of 0.1N hydrochloric acid. Methylprednisolone sodium succinate (30 mg/kg) was administered to nine dogs at 2, 8, and 24 hours after acid aspiration. Nine animals were untreated after aspiration and served as controls. Acid aspiration caused significant increases in venous admixture and reductions in Pao2 in both groups of animals. These changes persisted for 96 hours after aspiration. There were no differences in cardiac output, venous admixture, and blood gas values between treated and untreated animals at any time. At death there were no differences between groups in amounts of lung water or histologic characteristics. We concluded that methylprednisolone administered after hydrochloric acid aspiration does not affect resolution of the injury.

Animals↗

PubMed1983

Habitual physical activity and high-density lipoprotein cholesterol in men with primary hypercholesterolemia. The Lipid Research Clinics Coronary Primary Prevention Trial.

The association of habitual physical activity with plasma high-density lipoprotein (HDL) cholesterol and total triglyceride (TG) was examined in 7106 asymptomatic 35-59-year-old white men with primary type II hyperlipoproteinemia who attended the second screening visit of the Lipid Research Clinics Coronary Primary Prevention Trial. Subjects were rated by usual level of physical activity at work and outside of work and the frequency of strenuous physical labor or exercise. By each of these three criteria, physical activity was monotonically related to HDL cholesterol and TG: the most physically active men had the highest HDL cholesterol and lowest TG levels. With respect to physical activity outside of work, for example, mean HDL cholesterol and TG were 46.4 and 152.1 mg/dl, respectively, in the most active group, and 41.4 and 186.7 mg/dl in the most sedentary group. Physical activity remained significantly predictive of HDL cholesterol and TG when other known correlates of these plasma constituents--age, Quetelet index, plasma total cholesterol, cigarette smoking, alcohol intake, and clinic--were controlled individually by two-way analyses of variance or jointly by analysis of covariance. The association of physical activity with very low density lipoprotein cholesterol was parallel to but weaker than its association with TG. Low-density lipoprotein and total cholesterol were not significantly related to physical activity.

Adult↗

PubMed1982

The effect of antithrombotic therapy on patency rates of saphenous vein coronary artery bypass grafts.

In an attempt to improve upon the reported long-term patency rates of 65% to 85% for saphenous vein coronary artery bypass grafts (CABG), a prospective randomized trial comparing warfarin, aspirin, and placebo treatment in post-CABG patients was carried out. From an initial group of 216 patients, 161 patients remained in the study, and vein graft patency was determined in 111 patients (220 grafts) from 1 to 47 months postoperatively. There was a trend toward better cumulative graft patency in patients given warfarin, but the results did not achieve statistical significance. Improved results with warfarin were most marked among patients who were restudied within 24 months of CABG operation, in most instances because of the development of recurrent angina pectoris. There were four major bleeding complications of warfarin therapy, including one death, over 2,108 patient-months. Since most of the occlusive changes in vein grafts appear in the first 6 to 12 months, any effect of antithrombotic therapy will be most evident in the early postoperative period, with greatly reduced impact with long-term administration. Results of this study suggest that short-term antithrombotic therapy deserves further assessment in prevention of vein graft occlusion in the first year or two following a CABG operation. This potential benefit must be evaluated in the context of the recognized bleeding complications of warfarin therapy.

Adult↗

PubMed1975

An evaluation of a high resolution closed-circuit television link in a hospital radiology department.

We have installed and developed a high resolution closed-circuit television system for transmission of radiographic film images from the emergency room in our hospital to the reading room in our radiology department. Using this system, the radiologist can consult promptly on all films and he has increased efficiency. To transmit high detail images, our television system uses a high resolution vidicon camera with a scan rate of 1029 lines and with a limiting resolution of 1200 TV lines. To further increase the overall diagnostic value of our system, we have added remote controls for changing the magnification, illumination and position of the film. In a preliminary clinical trial, seven radiologists were each shown 27 patient film sets transmitted through the television system and then viewed directly on a conventional view box. An analysis of variance of the accuracy rates in each method showed a statistical difference in methods. Even though the error rate was slightly higher using closed-circuit system, radiologist performance was of acceptable accuracy when considering the advantages of the system. In addition, many of the factors reducing the TV system performance have been eliminated or controlled, and further experiments should reflect an even smaller difference between the two methods.

False Positive Reactions↗

PubMed1966