Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036690 (sepsis)
 59,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

TNF is a major mediator in the pathogenesis of endotoxic shock, and its inhibition has a protective effect in various animal models of sepsis or endotoxin (lipopolysaccharide, LPS) toxicity. LPS treatment also induces an oxidative damage mediated by increased production of reactive oxygen intermediates. N-Acetylcysteine (NAC) is an antioxidant and a precursor of the synthesis of glutathione (GSH) and was reported to protect against LPS toxicity and LPS-induced pulmonary edema. In this study we investigated the effect of NAC on TNF production and LPS lethality in mice. The results indicated that oral administration of NAC protects against LPS toxicity and inhibits the increase in serum TNF levels in LPS-treated mice. The inhibition was not confined to the released form of TNF, since NAC also inhibited LPS-induced spleen-associated TNF. On the other hand, the inhibitor of GSH synthesis, DL-buthionine-(SR)-sulfoximine (BSO), had the opposite effect of potentiating LPS-induced TNF production, and this was associated with a decrease in liver GSH levels. Repletion of liver GSH with NAC reversed this effect. NAC was also active in inhibiting TNF production and hepatotoxicity in mice treated with LPS in association with a sensitizing dose of Actinomycin D. These data indicate that GSH can be an endogenous modulator of TNF production in vivo. On the other hand, NAC pretreatment did not inhibit other effects of LPS, particularly induction of serum IL-6, spleen IL-1 alpha, and corticosterone, in the same experimental model, suggesting that the observed effect could be specific for TNF.
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PMID:N-acetylcysteine and glutathione as inhibitors of tumor necrosis factor production. 154 68

Endotoxin in the form of a lipooligosaccharide (LOS) plays a key role in the development of shock in meningococcal sepsis. To examine hemodynamic and biochemical alterations during meningococcal endotoxic shock, we established a rabbit model. Thirty-nine rabbits, weighing 2.5-4.4 kg, were studied. After anesthesia with intramuscular ketamine (20 mg/kg) and xylazine (4 mg/kg), femoral venous and arterial catheters were inserted. Control animals received only saline, while rabbits in each of four additional groups were given LOS in 10-fold increments from 0.1 microgram/kg to 100 microgram/kg. Mean arterial pressure (MAP), heart rate (HR), respirations (RR), temperature (T), urine output, and arterial blood gases (pH, PCO2, PO2, and bicarbonate) were determined at baseline and hourly. Endotoxin levels and TNF levels were measured at 30, 60, 120, 180, 240, 300, and 360 min post-LOS. Survival was recorded. One-way analysis of variance (ANOVA) and the Scheffe procedure, paired samples t-test, two-tailed t-test, and Fisher's exact test were used. Pearson's coefficients were calculated. Animals receiving meningococcal LOS developed tachycardia and compensated metabolic acidosis with an initially normal pH and MAP. With progression of the shock state, the pH decreased and hypotension ensued. Maximal levels of endotoxin were measured 30 min after LOS injection and declined during the ensuing 6 hr. TNF rose from undetectable to markedly elevated levels and peaked at 60-120 min post-LOS. Increasing the amount of injected endotoxin produced more profound degrees of shock until a dose of 10.0 micrograms/kg was reached. There was no correlation between serum TNF at 60 min and survival at 6 hr or 24 hr.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of meningococcal endotoxin in a rabbit model of shock. 158 1

Endotoxemia in patients can lead to sepsis and shock by activation of cellular and plasmatic systems. Corticosteroids are described to have a beneficial effect on these phenomena. In this study of controlled endotoxic shock, we investigated the protective effects of prophylactic corticosteroid treatment against activation of cellular and plasmatic systems. In this respect, a low-dose methylprednisolone (1 mg/kg body wt) treatment was compared with that of a high-dose methylprednisolone (40 mg/kg body wt) treatment. Endotoxin infusion induced death of all rabbits, which was associated with leukopenia, thrombopenia, increased levels of beta-glucuronidase, and leukotriene B4 (LTB4) and decreased levels of complement total hemolytic activity (CH50) and tissue plasminogen activator (t-PA) activity. Both methylprednisolone regimens prevented death of the rabbits after endotoxin infusion, which correlated with a significant decrease of the granulocyte release product beta-glucuronidase (P less than 0.01). The early leukopenia and thrombopenia were not prevented; however, both cell numbers returned more rapidly to baseline values than in the placebo group (P less than 0.01, P less than 0.05). The LTB4 and CH50 concentration and t-PA activity did not differ significantly between the treated and placebo groups. These results indicate that although methylprednisolone has no inhibitory effect on the activation of the complement, arachidonic acid, and fibrinolytic systems, it protected the animals from the deleterious effects of endotoxin shock by inhibition of leukocyte activation. In this regard a low dosage of methylprednisolone is equally effective as the most often recommended high dose.
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PMID:Methylprednisolone prophylaxis protects against endotoxin-induced death in rabbits. 164 35

Gram-negative sepsis/septic shock causes significant mortality in newborns. However, there has been no established method for newborn endotoxic shock treatment. Prostaglandins play a role in endotoxic shock. Cepharanthine is a biscoclaurine alkaloid that primarily inhibits phospholipase A2. Therefore, the effects of cepharanthine have been studied on endotoxic shock in newborn rats. Cepharanthine decreased the 24 h mortality of endotoxic shock in a dose-related manner. At the dose of 0.2 mg kg-1 it effectively reduced the mortality from 90 to 21% in newborn rats. It also induced hyperglycaemia in control rats and blunted the hypoglycaemia of endotoxic shock. Cepharanthine did not suppress body weight gain nor did it delay death as seen with glucocorticoid treatment. We conclude that cepharanthine is beneficial in the treatment of newborn endotoxic shock.
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PMID:Cepharanthine (biscoclaurine alkaloid) treatment in endotoxic shock of suckling rats. 168 Oct 76

The newborn is very susceptible to gram-negative sepsis/septic shock. The mortality of newborn endotoxic shock continues to be high. Since lipid A is responsible for the toxic effects of lipopolysaccharide, anti-lipid A antibodies may prevent endotoxic shock in the newborn. This study showed that both anti-lipid A monoclonal IgG (A78S1) and anti-lipid A monoclonal IgM (A523) decreased the mortality of endotoxic shock in 10 day old rats. Prophylactic administration of A78S1 and A523 to the pregnant rat decreased the mortality of endotoxic shock in their 0-day-old offspring. Prophylaxis was due to transplacental passage of A78S1 treatment. The mechanism of prophylaxis remains unclear in A523 treatment.
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PMID:Prophylaxis and treatment of newborn endotoxic shock with anti-lipid A monoclonal antibodies. 174 61

Hemorrhagic shock and encephalopathy syndrome (HSES) is a devastating symptom complex that affects previously healthy infants and is associated with significant mortality and neurologic morbidity. The syndrome was first reported less than ten years ago, and there continues to be debate regarding whether HSES actually represents a distinct clinical entity or instead is a manifestation of heat illness, occult sepsis or endotoxic shock, or perhaps toxic ingestion. Nevertheless, the signs and symptoms described as HSES present in a typical fashion in the emergency department with sudden onset of shock, encephalopathy, seizures, and coagulopathy. Even with the initiation of intensive support in the ED, the outcome is probably dismal. We describe a case of HSES and review the presentation, proposed etiologies, and management of this catastrophic illness.
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PMID:Hemorrhagic shock and encephalopathy syndrome. 174 41

Newborns are susceptible to gram-negative sepsis/septic shock, but there is no established method of its treatment. This study was performed to evaluate the adjuvant effects of dopamine and dobutamine in the indomethacin treatment of newborn endotoxic shock. Endotoxic shock was induced in newborn dogs (2 to 10 days old; 300 to 800 g) by Escherichia coli lipopolysaccharide (LPS; 1.5 mg/kg, intravenously [IV]). Indomethacin (1.5 mg/kg, IV) was injected 5 minutes after LPS injection. Dopamine (5 micrograms/kg/min) or dobutamine (5 micrograms/mg/min) infusion started 5 minutes after LPS injection immediately following indomethacin injection. Hemodynamic parameters were monitored serially for 120 minutes. LPS induced bradycardia and hypotension, decreased the cardiac output and cardiac performance, and increased the total vascular resistance. When dopamine, dobutamine, or indomethacin were used alone, they attenuated the hemodynamic deterioration by LPS. Dopamine infusion following indomethacin administration improved the hemodynamics further, although dobutamine infusion did not. Therefore, we conclude that the adjuvant therapy of dopamine in the indomethacin treatment of newborn endotoxic shock is beneficial.
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PMID:Adjuvant effects of beta-adrenergic drugs on indomethacin treatment of newborn canine endotoxic shock. 177 23

Various beneficial effects of calcium channel blockers on cell and organ function following endotoxic shock, organ ischemia, and reperfusion have been reported; however, it is not known whether these agents have any salutary or deleterious effects on immune responses after low-flow conditions. Therefore, the aim of this study was to determine (a) the effect of hemorrhage on lymphocyte IL-2, IL-3, IL-6, and IFN-gamma synthesis, and (b) whether diltiazem has any salutary or adverse effects on these parameters when administered following hemorrhage and resuscitation. To study this, C3H/HeN mice were bled to a mean blood pressure of 35 mm Hg, maintained at that level for 60 min, and resuscitated with shed blood plus twice that volume of Ringer's lactate. Immediately following resuscitation mice received either diltiazem (2400, 800, or 400 micrograms/kg body wt), or an equivalent volume of saline. The mice were sacrificed 24 hr later, splenic lymphocytes were obtained, and their capacity to produce lymphokines was assessed. The results indicated that in the vehicle-treated animals, hemorrhage significantly decreased (P less than 0.05) IL-2, IL-3, IL-6, and IFN-gamma synthesis by 82 +/- 19%, 64 +/- 28%, 71 +/- 11%, and 86 +/- 14%, respectively. However, diltiazem (400 but not 2400 micrograms/kg) treatment after hemorrhage restored lymphocyte capacity to produce IL-2, IL-3, IL-6, and IFN-gamma (P less than 0.05). Additional groups of animals were subjected to sepsis by cecal ligation and puncture 3 days following hemorrhage.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Diltiazem restores IL-2, IL-3, IL-6, and IFN-gamma synthesis and decreases host susceptibility to sepsis following hemorrhage. 190 99

Endotoxin is composed of lipid A, the toxic moiety, of the core region, a conserved structure among Gram-negative bacteria, and of the O-side chains, a highly variable part responsible for the antigenic specificity. The concept of cross-protection afforded by antiserum raised against the core region of endotoxin is supported by the following data: experimentally antiserum protected against infections caused by a wide range of Gram-negative bacteria or endotoxins; in patients with Gram-negative bacteremia, survival was associated with high levels of anti-core antibodies, and mortality was reduced by the prophylactic or therapeutic use of immune serum or plasma. However, the proof that protection is afforded by cross-protective anti-core antibodies is still lacking. Furthermore, many experimental studies and clinical studies trials have shown controversial results. Ongoing experimental studies and recently completed clinical trials, using either polyclonal or monoclonal anti-core antibodies should help clarify the issues both of the clinical efficacy and of the mechanism of protection. Tumor necrosis factor/cachectin has been unequivocally shown, both in experimental animal models and in humans to be a pivotal mediator of the clinical and humoral manifestations of shock induced by endotoxin or by whole Gram-negative bacteria. In humans, TNF was been transiently detected in the blood of volunteers challenged with endotoxin, in a small proportion of patients with Gram-negative sepsis, but in the vast majority of patients with established septic shock. However, in patients the magnitude and the evolution of the blood concentration of TNF differed from that observed in animal models or in human volunteers after an acute challenge with either Gram-negative bacteria or endotoxin, probably reflecting differences in infectious stimuli. In children with meningococemia and in adults with Gram-negative septic shock, TNF was associated with the patient's outcome. Anti-TNF monoclonal antibodies are presently undergoing clinical investigation in patients with septic shock. However, one should keep in mind that TNF serves both beneficial and detrimental functions depending upon its concentration in body fluids.
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PMID:Anti-lipopolysaccharide and anti-tumor necrosis factor/cachectin antibodies for the treatment of gram-negative bacteremia and septic shock. 192 24

Recent studies in alcoholic hepatitis have proposed a role for the cytokine tumour necrosis factor-alpha (TNF-alpha) a mediator of endotoxic shock in sepsis. In this study plasma levels of the closely related cytokine interleukin-6 (IL-6) were assayed in 96 samples from 58 patients with severe alcoholic hepatitis, and 69 patients in control groups (21 normal, 10 alcoholic without liver disease, 10 inactive alcoholic cirrhosis, 18 chronic liver disease, 10 chronic renal failure). Plasma IL-6 levels were markedly elevated in patients with alcoholic hepatitis when compared with all control groups (P less than 0.001). IL-6 levels were higher in patients who died (P = 0.04) and correlated with the features of severe disease including: increased grade of encephalopathy, increased neutrophil count, increased prothrombin ratio, hypotension, increased serum creatinine and increased serum bilirubin. Surprisingly, no correlation was found between levels of plasma IL-6 and plasma TNF-alpha or endotoxin, or the presence of infection; an inverse correlation was found between plasma IL-6 and serum globulins. These findings provide further evidence that the IL-6/TNF cytokine system is activated in severe alcoholic hepatitis and may mediate hepatic or extra-hepatic tissue damage.
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PMID:Elevated plasma interleukin-6 and increased severity and mortality in alcoholic hepatitis. 204 24


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