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Query: UMLS:C0036690 (
sepsis
)
59,461
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Vibrio vulnificus is an estuarian bacterium that causes
septicemia
and serious wound infection. The cytolysin, one of the important virulence determinants in V. vulnificus infection, has been reported to have lethal activity primarily by increasing pulmonary vascular permeability. In the present study, we investigated the cytotoxic mechanism of V. vulnificus cytolysin in cultured pulmonary artery endothelial (CPAE) cells, which are possible target cells of cytolysin in vivo. V. vulnificus cytolysin caused the CPAE cell damages with elevation of the cytosolic free Ca2+, DNA fragmentation, and decrease of the cellular NAD+ and ATP level. These cytotoxic effects of V. vulnificus cytolysin were prevented by EGTA and aminobenzamide, but were not affected by verapamil or
catalase
. These results indicate that the elevation of cytosolic free Ca2+ induced by V. vulnificus cytolysin causes the increase of DNA fragmentation and the damaged DNA activates nuclear poly(ADP-ribose) synthetase, which depletes the cellular NAD+ and ATP, resulting in cell death.
...
PMID:Cytotoxic mechanism of Vibrio vulnificus cytolysin in CPAE cells. 1200 77
Nitric oxide (*NO) and its by-products modulate many physiological functions of skeletal muscle including blood flow, metabolism, glucose uptake, and contractile function. However, growing evidence suggests that an overproduction of nitric oxide contributes to muscle wasting in a number of pathologies including chronic heart failure,
sepsis
, COPD, muscular dystrophy, and extreme disuse. Limited data point to the potential of inhibition various enzymes by reactive nitrogen species (RNS), including (.)NO and its downstream products such as peroxynitrite, primarily in purified systems. We hypothesized that exposure of skeletal muscle to RNS donors would reduce or downregulate activities of the crucial antioxidant enzymes superoxide dismutase (SOD),
catalase
(
CAT
), and glutathione peroxidase (GPX). Diaphragm muscle fiber bundles were extracted from 4-month-old Fischer-344 rats and, in a series of experiments, exposed to either (a) 0 (control), 1, or 5 mM diethylamine NONOate (DEANO: *NO donor); (b) 0, 100, 500 microM, or 1 mM sodium nitroprusside (SNP: *NO donor); (c) 0 or 2 mM S-nitroso-acetylpenicillamine (SNAP: *NO donor); or (d) 0 or 500 microM SIN-1 (peroxynitrite donor) for 60 min. DEANO resulted in a 50% reduction in
CAT
, GPX, and a dose-dependent inhibition of Cu, Zn-SOD. SNP resulted in significantly lower activities for total SOD, Mn-SOD isoform, Cu, Zn-SOD isoform,
CAT
, and GPX in a dose-dependent fashion. Two millimolar SNAP and 500 microM SIN-1 also resulted in a large and significant inhibition of total SOD and
CAT
. These data indicate that reactive nitrogen species impair antioxidant enzyme function in an RNS donor-specific and dose-dependent manner and are consistent with the hypothesis that excess RNS production contributes to skeletal muscle oxidative stress and muscle dysfunction.
...
PMID:Specificity of antioxidant enzyme inhibition in skeletal muscle to reactive nitrogen species donors. 1207 89
Shock states induce the expression of inducible nitric oxide synthase (iNOS) in both Kupffer cells and hepatocytes in the liver, but little is known about its subcellular localization in these cells. Studies were undertaken to characterize the subcellular location of iNOS in hepatocytes in response to
sepsis
. By immunofluorescence analysis, intraperitoneal challenge with bacterial lipopolysaccharide induced cytosolic iNOS in Kupffer cells but punctate labeling in hepatocytes. Cultured rat hepatocytes exposed to interferon gamma, interleukin 1, and tumor necrosis factor alpha showed iNOS protein expression within peroxisomes as early as 4 hours after stimulation, as determined by colabeling for
catalase
or PMP70. To a lesser extent, iNOS was also observed associated with the plasma membrane and in undefined intracellular aggregates. The nitric oxide synthase (NOS) antagonist L-N-imino-ornithine (L-NIO) did not affect the expression of iNOS within peroxisomes, cytoplasmic aggregates, or cytosol but increased plasma membrane localization of iNOS. Human iNOS transduced into iNOS-null mouse hepatocytes using an adenoviral vector also localized to peroxisomes. The expression of iNOS often resulted in the disappearance of detectable
catalase
in many hepatocytes. In conclusion, these studies establish the peroxisome as a site of iNOS localization in hepatocytes and show a relationship between iNOS up-regulation and decreased expression of
catalase
.
...
PMID:Peroxisomal localization of inducible nitric oxide synthase in hepatocytes. 1208 52
A 32 years old female was admitted to hospital due to acute abdominal pain, nausea, vomiting and liquid stools. Physical examination was normal except for pain on her left inferior abdominal quadrant without peritoneal irritation signs. An abdominal
CAT
-scan suggested thrombosis at celiac trunk, although the echo Doppler showed no alterations except for signs of ischemia in the distal branch of the superior mesenteric artery. An exploratory laparotomy was performed disclosing a necrosis of the distal ileum and cecum, diffuse peritonitis and thrombosis of the ileocecoapendiculocolic artery. No vasculitis lesions were found in the arteries of medium size examined. A history of intermittent claudication for the past 3 years as well as acrocyanosis, asymmetry of pulses and blood pressure in the superior extremities was ascertained after the surgery. A MRI angiogram showed multiple stenoses and irregularities at the celiac trunk, hepatic, superior mesenteric and fibular arteries. No abnormalities at the aortic arch and its main branches were documented. A
sepsis
due to Candida sp complicated her postoperative period. After recovery, prednisone 1 mg/kg/day was started and the anticoagulation continued. The abdominal pain, intermittent claudication and superior limb acrocyanosis disappeared. This is an unusual case of type IV Takayasu's arteritis with acute abdominal signs as the first manifestation.
...
PMID:[Intestinal necrosis as clinical presentation of Takayasu arteritis]. 1249 34
An increased extracellular production of free radicals with bactericidal activity does not improve the efficacy of intracellular digestion of Staphylococci. The amount of intracellular oxygen reactive species generated by the neutrophils from patients with an infectious condition has been found considerably decreased as compared to healthy donors. On the other hand, the excess of secretion of free radicals into the extracellular space leads inevitably to the adaptive increase of antioxidant enzymes and, as a result, to an increase in the total antioxidant capacity of the blood plasma. Indeed, patients with
septicemia
at its highest peak (at the moment of hospitalization) showed a significant increase (more than twice) in the parameters of
catalase
and superoxide dismutase activity; the antioxidant capacity of the plasma was elevated as well. The patients of the other two groups in our study (with a localized infection) did not show any statistically significant rise in these parameters. On the second day after the initiation of an intensive treatment the activity of the enzymes and the total antioxidant capacity of the plasma dropped sharply below the normal level. Therefore, the staphylococcus infection, especially its generalized from, is characterized by an increased extracellular secretion of radicals together with a decreased generation of intracellular radicals. On one hand this leads to the failure of the intracellular killing, on the other--to the inflammatory free radical-mediated damage of the host cells and tissues. Cytokines, such as interleukins and interferons, can regulate the free radical-mediated processes during the staphylococcus infections. The effect of the two recombinant cytokines (IL-1 beta, IFN-gamma) on the character of free radical production and intracellular killing of Staphylococci by neutrophils isolated from the blood of patients and healthy donors has been studied. The analysis of the effect of cytokines on the radical production by phagocytes revealed a redistribution of the extracellular and intracellular fractions of free radicals rather than a general increase of the oxygen active metabolite production. As expected, the increment in the number of intracellular radicals improved significantly the process of phagocytosis.
...
PMID:Effect of cytokines on the level of free radicals in the blood of patients with systemic and local staphylococcus infection. 1267 35
Burn trauma produces significant fluid shifts that, in turn, reduce cardiac output and tissue perfusion. Treatment approaches to major burn injury include administration of crystalloid solutions to correct hypovolemia and to restore peripheral perfusion. While this aggressive postburn volume replacement increases oxygen delivery to previously ischemic tissue, this restoration of oxygen delivery is thought to initiate a series of deleterious events that exacerbate ischemia-related tissue injury. While persistent hypoperfusion after burn trauma would produce cell death, volume resuscitation may exacerbate the tissue injury that occurred during low flow state. It is clear that after burn trauma, tissue adenosine triphosphate (ATP) levels gradually fall, and increased adenosine monophosphate (AMP) is converted to hypoxanthine, providing substrate for xanthine oxidase. These complicated reactions produce hydrogen peroxide and superoxide, clearly recognized deleterious free radicals. In addition to xanthine oxidase related free radical generation in burn trauma, adherent-activated neutrophils produce additional free radicals. Enhanced free radical production is paralleled by impaired antioxidant mechanisms; as indicated by burn-related decreases in superoxide dismutase,
catalase
, glutathione, alpha tocopherol, and ascorbic acid levels. Burn related upregulation of inducible nitric oxide synthase (iNOS) may produce peripheral vasodilatation, upregulate the transcription factor nuclear factor kappa B (NF-kappaB), and promote transcription and translation of numerous inflammatory cytokines. NO may also interact with the superoxide radical to yield peroxynitrite, a highly reactive mediator of tissue injury. Free radical mediated cell injury has been supported by postburn increases in systemic and tissue levels of lipid peroxidation products such as conjugated dienes, thiobarbituric acid reaction products, or malondialdehyde (MDA) levels. Antioxidant therapy in burn therapy (ascorbic acid, glutathione, N-acetyl-L-cysteine, or vitamins A, E, and C alone or in combination) have been shown to reduce burn and burn/
sepsis
mediated mortality, to attenuate changes in cellular energetics, to protect microvascular circulation, reduce tissue lipid peroxidation, improve cardiac output, and to reduce the volume of required fluid resuscitation. Antioxidant vitamin therapy with fluid resuscitation has also been shown to prevent burn related cardiac NF-kappaB nuclear migration, to inhibit cardiomyocyte secretion of TNF-alpha, IL-1beta, and IL-6, and to improve cardiac contractile function. These data collectively support the hypothesis that cellular oxidative stress is a critical step in burn-mediated injury, and suggest that antioxidant strategies designed to either inhibit free radical formation or to scavage free radicals may provide organ protection in patients with burn injury.
...
PMID:Free radicals and lipid peroxidation mediated injury in burn trauma: the role of antioxidant therapy. 1282 Dec 84
Skeletal muscle disuse with space-flight and ground-based models (e.g., hindlimb unloading) results in dramatic skeletal muscle atrophy and weakness. Pathological conditions that cause muscle wasting (i.e., heart failure, muscular dystrophy,
sepsis
, COPD, cancer) are characterized by elevated "oxidative stress," where antioxidant defenses are overwhelmed by oxidant production. However, the existence, cellular mechanisms, and ramifications of oxidative stress in skeletal muscle subjected to hindlimb unloading are poorly understood. Thus we examined the effects of hindlimb unloading on hindlimb muscle antioxidant enzymes (e.g., superoxide dismutase,
catalase
, glutathione peroxidase), nonenzymatic antioxidant scavenging capacity (ASC), total hydroperoxides, and dichlorohydrofluorescein diacetate (DCFH-DA) oxidation, a direct indicator of oxidative stress. Twelve 6 month old Sprague Dawley rats were divided into two groups: 28 d of hindlimb unloading (n = 6) and controls (n = 6). Hindlimb unloading resulted in a small decrease in Mn-superoxide dismutase activity (10.1%) in the soleus muscle, while Cu,Zn-superoxide dismutase increased 71.2%. In contrast,
catalase
and glutathione peroxidase, antioxidant enzymes that remove hydroperoxides, were significantly reduced in the soleus with hindlimb unloading by 54.5 and 16.1%, respectively. Hindlimb unloading also significantly reduced ASC. Hindlimb unloading increased soleus lipid hydroperoxide levels by 21.6% and hindlimb muscle DCFH-DA oxidation by 162.1%. These results indicate that hindlimb unloading results in a disruption of antioxidant status, elevation of hydroperoxides, and an increase in oxidative stress.
...
PMID:Hindlimb unloading increases oxidative stress and disrupts antioxidant capacity in skeletal muscle. 1282 51
Although Haemophilus somnus causes
septicemia
and vasculitis in cattle, relatively little is known about how H. somnus affects endothelial cells in vitro. We previously reported that H. somnus lipooligosaccharide (LOS)-induced activation of caspases-3, -8 and -9, and apoptosis of bovine pulmonary artery endothelial cells (BPAEC) in vitro. Previous reports indicate that the generation of reactive oxygen species (ROS) or reactive nitrogen intermediates (RNI) can contribute to the induction of apoptosis. In the present study, we sought to determine whether ROS and RNI are involved in LOS-mediated apoptosis of BPAEC. We found that H. somnus LOS induced the generation of ROS in BPAEC, which was blocked by pretreatment with membrane permeable ROS scavengers, such as dimethylsulfoxide (DMSO) and allopurinol (AP). Addition of DMSO or AP significantly reduced H. somnus LOS-mediated caspase-3 activation. Addition of membrane impermeable ROS scavengers (e.g.
catalase
and superoxide dismutase), failed to block LOS-mediated caspase-3 activation, suggesting a role for intracellular generation of ROS in LOS-induced apoptosis of BPAEC. Addition of N(G)-nitro-L-arginine methyl ester (L-NAME) or aminoguanidine, which are selective inhibitors of nitric oxide synthase, blocked NO release and significantly reduced caspase-3 activation in LOS treated BPAEC. These data suggest H. somnus LOS triggers endogenous ROS and RNI production by endothelial cells, which contributes to apoptosis.
...
PMID:Reactive oxygen and nitrogen intermediates contribute to Haemophilus somnus lipooligosaccharide-mediated apoptosis of bovine endothelial cells. 1474 Nov 39
The aim of this study was to investigate effects of sesame oil on oxidative stress after the onset of
sepsis
in rats. Effects of sesame oil on lipid peroxidation, superoxide anion, superoxide dismutase,
catalase
, glutathione, and nitrite after the onset of endotoxin intoxication were determined. To further examine the protective effect of sesame oil on
sepsis
, a mortality study was also conduced in cecal ligation and puncture-induced
sepsis
in rats. Sesame oil was given orally 6 h after endotoxin administration and cecal ligation and puncture, and parameters were then measured in another 6 h. Data demonstrated that a single dose of sesame oil reduced lipid peroxidation 6 h after endotoxin intoxication. Superoxide anion counts were decreased, glutathione levels were increased, and activities of superoxide dismutase and
catalase
, as well as nitrite levels, were not altered in lipopolysaccharide plus sesame oil-treated groups compared with lipopolysaccharide-treated groups. Furthermore, sesame oil given 6 h after cecal ligation and puncture significantly increased survival rate. Thus, we suggested that sesame oil could be used as a potent antioxidant to reduce oxidative stress after the onset of
sepsis
in rats.
...
PMID:Effects of sesame oil on oxidative stress after the onset of sepsis in rats. 1554 32
We investigated the role of oxidative stress in the pathogenesis of septic ileus.
Sepsis
was induced by intraperitoneal (i.p.) injection of lipopolysaccharides (LPS, 20 mg kg(-1)) in mice. The effect of two i.p. injections of superoxide dismutase [polyethylene glycol (PEG)-SOD, 4000 U kg(-1)] and
catalase
(PEG-
CAT
, 15,000 U kg(-1)) was investigated on gastric emptying, intestinal transit and total nitrite plasma concentrations. We also performed immunohistochemical experiments on gastric and ileal tissue. LPS significantly delayed gastric emptying and intestinal transit while plasma nitrite levels increased. Polyethylene glycol (PEG)-SOD reversed the endotoxin-induced delay in gastric emptying and improved the delay in intestinal transit without effect on plasma nitrite levels. PEG-
CAT
slightly improved the delay in gastric emptying without effect on intestinal transit. Immunohistochemistry showed the presence of nitrotyrosine (NT) and 4-hydroxy-2-nonenal (HNE) in the gastric and ileal mucosa of LPS-treated mice. Treatment with PEG-SOD or PEG-
CAT
of LPS mice diminished the presence of NT or HNE in both tissues. In addition, LPS induced a significant increase in inducible nitric oxide synthase (iNOS)-positive residential macrophages in the external musculature of stomach and ileum, which significantly decreased after PEG-SOD or PEG-
CAT
treatment. The present results support a role for oxidative and nitrosative stress in the pathogenesis of septic ileus in mice.
...
PMID:Role of oxidative stress in the pathogenesis of septic ileus in mice. 1578 45
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