BACKGROUND Previous studies have shown that a profound suppression of immune function transiently occurs in patients who undergo surgery under general anesthesia. The decline in the absolute counts of peripheral blood lymphocytes constitutes a major factor accounting for this immune defect, and recent evidence indicates that apoptosis plays a crucial role in determining postsurgical lymphocytop...

The release of cytochrome c from mitochondria is a crucial step in apoptosis, resulting in the activation of the caspase proteases. A further consequence of cytochrome c release is the enhanced mitochondrial production of superoxide radicals (O2.), which are converted to hydrogen peroxide by manganese-superoxide dismutase. Recently, we showed that cytochrome c is a potent catalyst of 2',7'-dich...

The endothelium plays an important role in maintaining vascular homeostasis by synthesizing and releasing several mediators of vasodilation, which include prostacyclin (PGI(2)), nitric oxide, and endothelium-derived hyperpolarizing factor (EDHF). We have recently defined the role of nitric oxide and PGI(2) in the dilation of submucosal intestinal arterioles from patients with normal bowel funct...

The mechanism by which dipicolylamine (DPA) chelate-appended fluorophores respond to zinc was investigated by the synthesis and study of five new analogs of the 2′,7′-dichlorofluorescein-based Zn2+ sensor Zinpyr-1 (ZP1). With the use of absorption and emission spectroscopy in combination with potentiometric titrations, a detailed molecular picture has emerged of the Zn2+ and H+ binding properti...

The use of antioxidants to prevent intracellular free radical damage is an area currently attracting considerable research interest. The compound 2',7'-dichlorofluorescin diacetate (DCFH-DA) is a probe for intracellular peroxide formation commonly used in such studies. During our studies we unexpectedly found that incubation of Trolox, a water soluble vitamin E analog, with DCFH-DA in cell-free...

A reliable ultramicro modification of the Franco and Klein (1) determination for chloride, using 20 pi. of plasma, is described. A second procedure, requiring 0.2 ml. of plasma and substituting a titrating syringe for a buret, is suggested as a fast and adequate substitute in the absence of either extensive laboratory facilities or trained personnel. Data on reproducibility and recovery, and a ...

PURPOSE We investigated a potential hepatoprotective role of d-cis diltiazem, l-cis diltiazem, thiamine and the combination d-cis diltiazem and thiamine against lipid peroxidation in a piglet liver microsomal model. A modified in vitro dichlorofluorescein assay was developed to assess the extent of peroxidative damage induced by reactive oxygen species in the piglet liver microsomal fraction. ...

Coronatine (COR), a structural and functional mimic of jasmonates, is involved in wide array effects on plant development defense response. The present study aims to investigate the role COR, counteracting drought stress by modulating reactive oxygen species (ROS) homeostasis, water balance, antioxidant regulation detached maize plants. Our results showed that COR can markedly decrease loss rat...

One of the objectives of studying endothelial cells in vitro is to evaluate neutrophil-endothelial cell interactions including potential consequences of oxidant-mediated damage to the endothelial cell. Current understanding of endothelial cell oxidative function is derived primarily from the measurement of extracellular products. We utilized 2 dyes, 2',7'-dichlorofluorescein diacetate (DCFH-DA)...

BACKGROUND Alpha-adrenergic receptor (alphaAR)-stimulated hypertrophy in adult rat ventricular myocytes is mediated by reactive oxygen species-dependent activation of the Ras-Raf-MEK1/2-ERK1/2 signaling pathway. Because Ras is known to have redox-sensitive cysteine residues, we tested the hypothesis that alphaAR-stimulated hypertrophic signaling is mediated via oxidative modification of Ras thi...