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Biomedical subjects

R P Goodman

Publications and source records attributed to R P Goodman.

27 records · Page 2Linked to original sources
PubMed1982

Assessment of the extent to exogenous prostaglandin I2 is converted to 6-keto-prostaglandin E1 in human subjects.

6-Keto-prostaglandin (PG) E1 has been suggested as a possible active metabolite of PGI2. The objective of this study was to evaluate whether 6-keto-PGE1 might mediate the biological responses of exogenous PGI2 in man. Toward this end, a novel gas chromatographic-mass spectrometric assay for 6-keto-PGE1, was developed. Selective ion monitor traces from human plasma detected levels that were at the lower limit of sensitivity for this assay and positive mass spectral identification was not possible. An infusion of PGI2 (8 ng/kg/min) which caused systemic hemodynamic changes did not alter plasma levels of 6-keto-PGE1. We conclude that exogenous PGI2 is not converted to an appreciable extent to 6-keto-PGE1 in man and, therefore, 6-keto-PGE1 biosynthesis is unlikely to be responsible for the biological effects of infused PGI2.

Adult↗
PubMed1981

Measurement of 5,8,11, 14-icosatetraynoic acid in plasma by gas-liquid chromatography.

A gas-liquid chromatography-flame ionization detection method is described for measuring plasma levels of eicosatetraynoic acid using eicosatriynoic acid as an internal standard. The technique is simple, rapid, and reproducible. Eicosatetraynoic acid and eicosatriynoic acid behave similarly in the extraction system chosen, yet can be easily resolved by gas-liquid chromatography. Under the conditions of our assay, most plasma fatty acids have a short retention time and are found near the solvent front, whereas, eicosatetraynoic acid and eicosatriynoic acid are retained for 6.9 and 3.75 minutes, respectively.

5,8,11,14-Eicosatetraynoic Acid↗
PubMed1977

Malignant chondromyxoid fibroma of the scapula.

A rare case of malignant chondromyxoid fibroma developed in the scapula of a woman who was treated with interscapulothoracic resection. When a biopsy specimen was submitted for study, difficulty was encountered in establishing the histologic diagnosis. A large dose of radiation was given before surgery, based on an original biopsy diagnosis of osteosarcoma; in retrospect, preoperative irradiation probably was contraindicated. Two years and four months after surgery, the patient was working with no evidence of recurrence or metastasis.

Adult↗
PubMedDate not supplied

The effect of ranitidine and cimetidine on single-dose diltiazem pharmacokinetics.

The effects of two histamine 2-receptor antagonists, cimetidine and ranitidine, on the single-dose pharmacokinetics of diltiazem were studied in 6 healthy subjects. A single 60-mg oral dose of diltiazem was administered alone, after ranitidine 150 mg twice daily for 7 days, and after cimetidine 300 mg 4 times a day for 7 days. Plasma samples were obtained over a 10-hour period and analyzed for the parent drug and one of its metabolites, deacetyldiltiazem (DAD). Concurrent cimetidine produced a significant (p less than 0.05) increase in diltiazem levels at most time points, in peak concentration and area under the concentration-time curve. These variables were also increased during concurrent ranitidine administration but did not reach statistical significance. The DAD plasma concentration was below measurable levels during the control phase but increased during concurrent cimetidine and ranitidine administration. Caution should be exercised when diltiazem is administered concurrently with cimetidine and possibly, ranitidine.

Adult↗
PubMedDate not supplied

The effect of low-dose hydrochlorothiazide on blood pressure, serum potassium, and lipoproteins.

Recent clinical trials in hypertension suggest that thiazide diuretics may increase coronary heart deaths in selected patients, possibly through adverse effects on serum potassium, lipids, lipoproteins, and/or apolipoproteins. Administration of smaller doses of diuretics has been recommended to decrease this risk. We evaluated 12.5-mg and 112.5-mg daily doses of hydrochlorothiazide (HCTZ) administered for 1 month to nine postmenopausal black female hypertensives using a double-blind, randomized, crossover design. Both regimens produced significant reductions in sitting diastolic blood pressure, a mean of 11 mm Hg with the high dose and 8 mm Hg with the low dose. The high dose produced a mean 0.7 mEq/L reduction in serum potassium while the low dose caused no change. Both doses produced similar changes in serum lipoproteins. Statistically significant elevations were seen in total cholesterol (approximately 12%), LDL cholesterol (approximately 20%), cholesterol: HDL ratio (approximately 15%), and apolipoprotein B (approximately 20%). Apolipoprotein A1 was significantly reduced (approximately 6%). These results support the use of low doses of HCTZ in mild hypertension to avoid hypokalemia, but suggest that adverse changes in serum lipids will occur.

Apolipoproteins↗
PubMedDate not supplied

Use of antihypertensive agents in patients with glucose intolerance.

The selection, use, and potential adverse effects of antihypertensive agents in patients with glucose intolerance are reviewed. Thiazide diuretics frequently impair glucose tolerance, but this deterioration is usually modest and should not preclude use of these agents in most patients with glucose intolerance. The loop diuretics furosemide and ethacrynic acid have also been associated with decreased glucose tolerance. The beta-adrenergic blocking agents may inhibit insulin secretion, but few patients will experience clinically important elevations in blood glucose. Rather than producing glucose intolerance, these agents may delay recovery from hypoglycemic episodes and may mask catecholamine-induced symptoms of hypoglycemia. In certain cases, use of cardioselective beta blockers or avoidance of beta-blocker therapy may be indicated, especially in insulin-dependent diabetics. The calcium-channel blocking agents nifedipine and verapamil have been reported to produce diabetogenic effects in a few studies, but further investigations are needed to define the extent of these effects. Available evidence indicates that sympatholytic agents such as guanethidine and reserpine, alpha 2-adrenergic agonists such as methyldopa and clonidine, the alpha 1-blocking agent prazosin, and the vasodilators captopril and hydralazine produce few, if any, clinically important changes in glucose tolerance. While no antihypertensive agents are absolutely contraindicated in patients with glucose intolerance, patients with glucose intolerance who are receiving thiazide diuretics, beta blockers, and calcium-channel blocking agents should be monitored with extra care for hyperglycemia or deterioration in glucose tolerance.

Adrenergic alpha-Agonists↗