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N J Gilmore

Publications and source records attributed to N J Gilmore.

9 recordsLinked to original sources
PubMed1977

Airway mucosal permeability in the Ascaris suum-sensitive rhesus monkey.

The permeability of the airways to technetium 99m-labeled albumin was measured in Ascaris suum-sensitive rhesus monkeys. All 8 animals were skin-sensitive to Ascaris suum (AA) antigen, 4 being respiratory responders (R) and 4 nonresponders (NR) to aerosolized antigen. In the absence of antigen challenge there were no differences in the accumulation in the blood of radioactive material from the tracheobranchial tree between the R and NR animals. After a five-minute challenge with aerosolized AA, there was a threefold increase in the rate of accumulation of radioactive material in the blood over control for the R group with no effect noted in the NR group. Gel filtration data indicated that the radioactivity in the blood most likely represented low molecular weight albumin fragments, resulting from spontaneous degradation of Tc-albumin, that crossed the mucosa and partially bound to circulating albumin. It is concluded that hyperpermeability of the airway mucosa probably is not a factor that contributes to the selective responsiveness of the R group to aerosolized antigen, and that airway permeability is increased consequent to the allergic reaction mediating acute bronchoconstriction.

Aerosols↗
PubMed1976

Fibrinolysis in normal plasma and blood: evidence for significant mechanisms independent of the plasminogen-plasmin system.

Fibrinolytic activity of normal plasma and blood has been measured by 125l-fibrin solid phase assay. Activity of plasma is not affected by removal of plasminogenplasmin by affinity chromatography. Activities of euglobulin and pseudoglobulin fractions are approximately equal. epsilon-aminocaproic acid (EACA) (10 mM), tranexamic acid (10 mM), diisopropylfluorophosphate (DFP, 50 mM), and soybean and lima bean trypsin inhibitors (100 mug/ml) do not inhibit plasma activity at concentrations that inhibit pure plasmin and urokinase-activated plasma. Activity is not affected by glass contact and is not inhibited by inhibitors of contact or enzymatic activation of Hageman factor (hexadimethrine bromide, 100 mug/ml; cytochrome C, 250 mug/ml; spermidine, 2 mM; phenylmethylsulfonylfluoride, 1 mM). It is inhibited partially (30%-40%) by heating (56 degrees C, 30 min) and by zymosan (2.5 mg/ml; 40%-90% inhibition), and is increased by hydrazine (20 mM), salicylaldoxime (20 mM), DFP (50 mM), and tosyl-L-arginine methyl ester (TAMe, 10 mM)-the latter two at concentrations known to inhibit Cls of the classic, and factor D of the alternate complement pathways. Increase fibrinolytic activity with TAMe is associated with reciprocal decrease in classic and alternate complement pathway activity. It is concluded that normal plasma fibrinolytic activity is relatively independent of plasmin as the ultimate fibrinolytic enzyme, that Hageman factor-dependent pathways are of minor importance, and that significant heat-stable and heat-labile nonplasmin fibrinolytic activities are operative. These may include proteinases involved in complement activation, and in common control of classic and alternate complement pathways, as well as other nonplasmin proteinases.

Aminocaproates↗
PubMed1976

Mechanisms involved in enhancement of plasma fibrinolytic activity by chloroform.

The effects of a single 1-min extraction with chloroform (CHCl3) on plasma fibrinolytic activity has been examined by 125I-fibrin solid phase assay, using normal plasma and plasma depleted of plasminogen (PLG) by lysine-Sepharose affinity chromatography. Fibrinolytic activity of normal plasma is increased (40%-175%), and more than 95% of antiplasmin activity is removed. The increase is demonstrable in PLG-depleted plasma, and is not inhibited by tranexamic acid (0.01 M). Purified PLG is not activated to plasmin by ChCl3 treatment. Bio-Gel A 0.5 m fractionation of CHCl3-extracted, PLG-depleted plasma reveals fractions with the following activities: (1) streptokinase-activatable, PLG-independent fibrinolytic activities; (2) PLG activator activities; and (3) plasmin-stimulated but PLG-independent fibrinolytic activities, which include activities inhibited by hexadimethrine bromide and which cofractionate in part with plasmin-stimulated procoagulant activities. In addition, similar fractionation of nonextracted plasma reveals two non-plasmin fibrinolytic activities (approximately 30,000 and 13,000 daltons) activated by streptokinase and plasmin, respectively. The findings indicate that the enhanced fibrinolytic activity resulting from CHCl3 treatment is independent of plasmin as the ultimate fibrinolytic enzyme, although activities stimulated by plasmin may contribute, and that such treatment is a useful maneuver for study of PLG-dependent and PLG-independent fibrinolytic mechanisms, and their interactions.

Blood Coagulation↗
PubMed1975

A rapid and sensitive 125I-fibrin solid-phase fibrinolytic assay for plasmin.

125I-fibrinogen, adsorbed to polystyrene tubes at low ionic strength and treated with thrombin, serves as a substrate for a rapid, convenient, and sensitive test tube assay for plasmin and activators and inhibitors of this enzyme. 125I-labeled digestion products released from the 125I-fibrin-polystyrene matrix are readily separated and quantitated and behave, on gel permeation, in the same manner as plasmin-generated degradation products from an unlabeled conventional fibrin clot. The 125I-fibrin, in probable non-cross-linked form, is firmly bound to the polystyrene and is resistant to nonspecific release, with control (no enzyme) values equivalent to 15.2 ng +/- 1.2 (SD) fibrin (1% of the total bound 125I-fibrin). This fact permits consistent detection of lysis of 30-50 ng 125I-fibrin, which exceeds published sensitivities (1000-5000 ng) using 125I- or fluorochrome-labeled fibrin clots as substrate. The sensitivity for plasmin (0.2 mug/ml) is tenfold greater than that of the fibrin-plate method (2.0-2.5 mug/ml), while sensitivities for streptokinase and urokinase activation of plasmin are 0.02 U/ml and 0.04 CTA U/ml, respectively (sensitivity of fibrin-plate method, 0.5 U/ml for both). The method provides a reasonable analogue of the solid-phase nature of fibrin under physiologic conditions, and the ease of preparation of large batches of tubes makes the method suitable for large-scale screening of factors modulating the plasminogen-plasmin system.

Aminocaproates↗