Pulmonary complications after bone marrow transplantation: high-resolution CT and pathologic findings

The explosion of new knowledge about the complex mechanisms mediating high blood pressure is providing new targets for drug therapy of hypertension and other cardiovascular disorders. This article reviews the current status of several new approaches in the management of hypertension, including vasopressin antagonists, natriuretic peptide clearance inhibitors, endothelin antagonists, renin inhibitors, angiotensin receptor antagonists, and selective T-type calcium ion channel antagonists.     

Tailed. New options in therapy of bronchial asthma

A correct access opening is the key to endodontics. An adequate anatomical access preparation maximizes cleaning, shaping, and obturation. The major objectives of access preparation are straight line access to the apical area, conservation of tooth structure, and unroofing of the pulp chamber. The safe-ended diamond bur technique provides an efficient and rapid means to obtain the objective of access preparation in posterior teeth.     

Crystal structure of the S-nitroso form of liganded human hemoglobin

Although numerous reports have documented that the S-nitrosylation of cysteine residues by NO alters the activities of a wide variety of proteins, the direct visualization and the structural consequences of this reversible modification have not yet been reported for any protein. Here we describe the crystal structure of S-nitroso-nitrosylhemoglobin determined at a resolution of 1.8 A. The specific reaction of NO with Cys93beta is confirmed in this structure, and a large S-nitrosylation-induced change in the tertiary structure of the COOH-terminal dipeptides of the beta subunits provides additional insight into the stereochemical mechanism by which blood flow is regulated by the interaction of NO with hemoglobin.     

Increased response to antigen and histamine release in smaller sensitized canine bronchi

Presynaptic alpha 2-autoreceptors in mouse atria were characterized in terms of the alpha 2A, alpha 2B, alpha 2C and alpha 2D subtypes. Segments of the atria were preincubated with 3H-noradrenaline and then superfused and stimulated electrically. The affinity of up to 16 antagonists for the autoreceptors was assessed as (1) pEC30% values. i.e. concentrations that increased previously autoinhibited release of 3H-noradrenaline (120 pulses, 3 Hz) by 30%, and (2) pKd values against the release-inhibiting effect of 5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline (UK 14,304) under conditions of no or little autoinhibition (2 trains of 20 pulses, 50 Hz, train interval 120 s). The pKd values correlated well with the pEC30% values (r = 0.98; P < 0.001; slope of regression line 0.93), indicating that UK 14,304 and released noradrenaline modulated the release of noradrenaline through pharmacologically identical receptors. Comparison with antagonist affinities for (1) prototypic native alpha 2 radioligand binding sites, (2) radioligand binding sites in COS cells transfected with alpha 2 subtype genes, and (3) previously classified presynaptic alpha 2-autoreceptors-all taken from the literature-indicated that the mouse atrial autoreceptors corresponded to the alpha 2D subtype. For example, the pKd values at mouse atrial auto-receptors correlated closely with pKd values at native alpha 2D binding sites in the bovine pineal gland (r = 0.96; P < 0.001); with pKd values at alpha 2D binding sites in COS cells transfected with the rat alpha 2D gene (r = 0.85; P < 0.01); and with pKd values at guinea-pig cerebral and atrial and mouse cerebral alpha 2D-autoreceptors (r = 0.96-0.98; P < 0.001). The antagonist pKd values at mouse atrial autoreceptors correlated less with pKd values at alpha 2A, alpha 2B and alpha 2C sites. It is concluded that the presynaptic alpha 2-autoreceptors in mouse atria are alpha 2D. This identification supports the hypothesis that at least the majority of alpha 2-autoreceptors belong to the alpha 2A/D pair of orthologous alpha 2-adrenoceptors.