An important component of the antianginal efficacy of glyceryl trinitrate (GTN) is attributable to its selective venodilator effect, resulting in decreased cardiac preload and myocardial oxygen demand. Tolerance to nitrates occurs during chronic exposure, and the current study assessed whether this was due to increased phosphodiesterase (PDE) activity in the venous circulation. Tolerance was in...

BACKGROUND An hCG regression curve has been used to predict the natural history and response to chemotherapy in gestational trophoblastic disease. We constructed hCG regression curves in high-risk gestational trophoblastic neoplasia (GTN) treated with EMA/CO and identified an optimal hCG level to detect EMA/CO resistance in GTN. MATERIALS AND METHODS Eighty-one women with GTN treated with EMA...

OBJECTIVES The purpose of this study was to investigate whether therapy with nitroglycerin (GTN) would lead to abnormal coronary artery responses to the endothelium-dependent vasodilator acetylcholine. BACKGROUND Nitroglycerin therapy is associated with specific biochemical changes in the vasculature that may lead to increased vascular sensitivity to vasoconstrictors. METHODS Patients were ...

Mitochondrial aldehyde dehydrogenase (ALDH2) may be involved in the biotransformation of glyceryl trinitrate (GTN), and the inactivation of ALDH2 by GTN may contribute to the phenomenon of nitrate tolerance. We studied the GTN-induced inactivation of ALDH2 by UV/visible absorption spectroscopy. Dehydrogenation of acetaldehyde and hydrolysis of p-nitrophenylacetate (p-NPA) were both inhibited by...

Nitrate tolerance developed after persistent nitroglycerin (GTN) exposure limits its clinical utility. Previously, we have shown that the vasodilatory action of GTN is dependent on endothelial nitric oxide synthase (eNOS/NOS3) activity. Caveolin-1 (Cav-1) is known to interact with NOS3 on the cytoplasmic side of cholesterol-enriched plasma membrane microdomains (caveolae) and to inhibit NOS3 ac...

In this paper, four plastic instability criteria, which are based on the bifurcation theory, coupled with GTN damage model for prediction of diffuse and localized necking. General (GB) criterion limit-point (LPB) used to predict necking, while loss ellipticity (LOE) strong (LOSE) The resulting constitutive equations criteria implemented into finite element code ABAQUS/Standard. formulated withi...

OBJECTIVES This study was designed to assess the effect of oral L-arginine on the development of tolerance during continuous transdermal nitroglycerin (TD-GTN) therapy. BACKGROUND Continuous TD-GTN therapy leads to complete tolerance within 24 to 48 h. The mechanism(s) responsible for nitrate tolerance are unclear, but there is increasing evidence that nitroglycerin (GTN) leads to superoxide ...

Abstract We explore the acceleration effect on genuine tripartite nonlocality (GTN) for one or two accelerated detector(s) coupled to vacuum field with initial mixed states. show that Hawking radiation degrades physically accessible GTN, which suffers from “sudden death” at certain critical temperature. An novel phenomenon has been observed first time can generate inaccessible GTN fermion field...

In this paper, the initial and maximum load was studied using Finite Element Modeling (FEM) analysis during impact testing (CVN) of pipeline X70 steel. The Gurson-Tvergaard-Needleman (GTN) constitutive model has been used to simulate growth voids deformation steel at different temperatures. FEM simulations results study sensitivity with GTN parameters values proposed variation Finally, applied ...

The flavoprotein inhibitor, diphenyleneiodonium (DPI), inhibits the action of glyceryl trinitrate (GTN) and the D-enantiomer of isoidide dinitrate (IIDN), but not the L-enantiomer (L-IIDN), in isolated rat aorta via inhibition of the bioactivation of these prodrugs. Paradoxically, a vascular NAD(P)H oxidase, which also is inhibited by DPI, has been proposed to generate superoxide that quenches ...