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D Beeler

Publications and source records attributed to D Beeler.

3 recordsLinked to original sources
PubMed1987

Fish-oil fatty acid supplementation in active rheumatoid arthritis. A double-blinded, controlled, crossover study.

STUDY OBJECTIVE: to determine the efficacy of fish-oil dietary supplements in active rheumatoid arthritis and their effect on neutrophil leukotriene levels. DESIGN: nonrandomized, double-blinded, placebo-controlled, crossover trial with 14-week treatment periods and 4-week washout periods. SETTING: academic medical center, referral-based rheumatology clinic. PATIENTS: forty volunteers with active, definite, or classical rheumatoid arthritis. Five patients dropped out, and two were removed for noncompliance. INTERVENTIONS: treatment with nonsteroidal anti-inflammatory drugs, slow-acting antirheumatic drugs, and prednisone was continued. Twenty-one patients began with a daily dosage of 2.7 g of eicosapaentanic acid and 1.8 g of docosahexenoic acid given in 15 MAX-EPA capsules (R.P. Scherer, Clearwater, Florida), and 19 began with identical-appearing placebos. The background diet was unchanged. MEASUREMENTS AND MAIN RESULTS: the following results favored fish oil placebo after 14 weeks: mean time to onset of fatigue improved by 156 minutes (95% confidence interval, 1.2 to 311.0 minutes), and number of tender joints decreased by 3.5 (95% Cl, -6.0 to -1.0). Other clinical measures favored fish oil as well but did reach statistical significance. Neutrophil leukotriene B4 production was correlated with the decrease in number of tender joints (Spearman rank correlation r=0.53; p less than 0.05). There were no statistically significant differences in hemoglobin level, sedimentation rate, or presence of rheumatoid factor or in patient-reported adverse effects. An effect from the fish oil persisted beyond the 4-week washout period. CONCLUSIONS: fish-oil ingestion results in subjective alleviation of active rheumatoid arthritis and reduction in neutrophil leukotriene B4 production. Further studies are needed to elucidate mechanisms of action and optimal dose and duration of fish-oil supplementation.

Adult↗
PubMed1979

Fractionation of low molecular weight heparin species and their interaction with antithrombin.

Preparations of low molecular weight porcine heparin with an average specific anticoagulant activity of 94 units/mg were fractionated into "active" and "relatively inactive" forms of the mucopolysaccharide of approximately 6000 daltons each. The active fraction was further subdivided into various species with descending but significant affinities for the protease inhibitor as well as decreasing but substantial anticoagulatn potencies. "Highly active" heparin (approximately 8% of the low molecular weight pool) possesses a specific anticoagulant activity of 350 +/- 10 units/mg. The relatively inactive fraction (67% of the low molecular weight pool) exhibits a specific anticoagulant activity of 4 +/- 1 units/mg. The binding of highly active heparin to antithrombin is accurately described by a single-site binding model with a KHep-ATDISS of approximately 1 X 10(-7) M. Variations in this binding parameter secondary to changes in environmental variables indicate that charge-charge interactions as well as an increase in entropy are critical to the formation of the highly active heparin-antithrombin complex. The interaction of relatively inactive heparin with the protease inhibitor is characterized by an apparent KHep-ATDISS of 1 X 10(-4) M. In large measure, this is due to small amounts of residual active mucopolysaccharide (0.5%). The ability of the highly active heparin to accelerate the thrombin-antithrombin interaction was also examined. We were able to demonstrate that the mucopolysaccharide acts as a catalyst in this process and is able to initiate multiple rounds of enzyme-inhibitor complex formation. The rate of enzyme neutralization is increased to a maximum of 2300-fold as the concentration of heparin is raised until the inhibitor is saturated with mucopolysaccharide. Further increases in heparin concentration result in a reduction in the speed of enzyme neutralization. This appears to be due to the formation of thrombin-heparin complexes. A mathematical model is given which provides a relationship between the initial velocity of enzyme neutralization and reactant concentrations.

Antithrombins↗