Role of the L-citrulline/L-arginine cycle in iNANC nerve-mediated nitric oxide production and airway smooth muscle relaxation in allergic asthma.

Nitric oxide synthase (NOS) converts L-arginine into nitric oxide (NO) and L-citrulline. In NO-producing cells, L-citrulline can be recycled to L-arginine in a two-step reaction involving argininosuccinate synthase (ASS) and -lyase (ASL). In guinea pig trachea, L-arginine is a limiting factor in neuronal nNOS-mediated airway smooth muscle relaxation upon inhibitory nonadrenergic noncholinergic (iNANC) nerve stimulation.

Arginase strongly impairs neuronal nitric oxide-mediated airway smooth muscle relaxation in allergic asthma.

Background: Using guinea pig tracheal preparations, we have recently shown that endogenous arginase activity attenuates inhibitory nonadrenergic noncholinergic (iNANC) nerve-mediated airway smooth muscle relaxation by reducing nitric oxide (NO) production--due to competition with neuronal NO-synthase (nNOS) for the common substrate, L-arginine. Furthermore, in a guinea pig model of allergic asthma, airway arginase activity is markedly increased after the early asthmatic reaction (EAR), leading to deficiency of agonist-induced, epithelium-derived NO and subsequent airway hyperreactivity. In this study, we investigated whether increased arginase activity after the EAR affects iNANC nerve-derived NO production and airway smooth muscle relaxation.

Thrombosis and hemorrhage in heparin-induced thrombocytopenia in seriously ill patients.

Objective: Heparin-induced thrombocytopenia (HIT) is the most common form of drug-induced immune-mediated thrombocytopenia. HIT may be aggravated by life-threatening arterial and venous thrombosis and, to a lesser extent, hemorrhagic complications. We investigated the incidence of thromboembolic and hemorrhagic complications in critically ill patients with the multiple organ dysfunction syndrome and HIT.

No benefit of intraoperative whole blood sequestration and autotransfusion during coronary artery bypass grafting: results of a randomized clinical trial.

Objectives: In a randomized clinical trial of patients undergoing elective coronary artery bypass grafting, we evaluated the effect of intraoperative whole blood sequestration and autotransfusion on postoperative blood loss and the use of allogeneic blood products.

Methods: Male patients were included if it was possible to obtain at least 500 mL of autologous blood. For patients in group H (heparin autotransfusion, 50 patients; mean age 59 +/- 8 years), an average of 670 +/- 160 mL heparinized blood was drawn before bypass and reinfused after the period of the extracorporeal circulation.

S100 protein content of umbilical cord blood in healthy newborns in relation to mode of delivery.

Background: Early detection and quantification of brain damage in neonatal asphyxia is important. In adults, S100 protein in blood is associated with damage to the central nervous system.

Objective: To determine whether S100 protein can be detected in arterial and venous cord blood of healthy newborns and to relate S100 protein concentrations in cord blood to mode of delivery.