Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: HUMANGGP:009512 (tumor necrosis factor)
 58,417 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In vitro plasma perfusion experiments were performed using small columns containing either resin or charcoal adsorbents to assess the removal of cytokines and endotoxin. 125I-labelled tumor necrosis factor-alpha (TNF-alpha; 500 pg/ml) and interleukin-6 (IL-6; 10 ng/ml) were added individually to human plasma. Over 4 hr of perfusion, Amberlite XAD-7 resin removed 32.5% +/- 3.3% (n = 5) of the initial amount of TNF-alpha and 71.4% +/- 3.8% (n = 5) of the initial amount of IL-6. DHP-1 polyhema-coated activated charcoal removed 17.2% +/- 6.2% (n = 5) of TNF-alpha and 48.5% +/- 7.4% (n = 5) of IL-6. Preliminary experiments were performed with lipopolysaccharide (LPS; 100 ng/ml) and interleukin-1 alpha (IL-1 alpha; 500 pg/ml), which showed that, over 4 hr, Amberlite XAD-7 removed 10.3% of the initial LPS and 29.1% of IL-1 alpha, whereas DHP-1 charcoal removed 23.2% of the initial LPS and 65.3% of IL-1 alpha. In vitro plasma ultrafiltration with either polysulfone or polyacrylonitrile membranes, as used clinically in haemodialysis, was performed with recirculation of plasma containing LPS or TNF-alpha. Neither of the substances was filtered to a significant degree. In conclusion, direct removal of these inflammatory mediators from the circulation of patients with multiorgan failure due to fulminant hepatic failure or sepsis would be possible by perfusion of plasma through adsorbents but not by haemodialysis.
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PMID:In vitro plasma perfusion through adsorbents and plasma ultrafiltration to remove endotoxin and cytokines. 129 81

We investigated plasma levels of cytokines and endotoxin in septic shock to clarify the roles of various cytokines in this type of shock. Endotoxemia was observed in 16 of 22 septic shock patients. Plasma levels of tumor necrosis factor-alpha (TNF-alpha), interleukin 1 beta (IL-1 beta) IL-2, and IL-6 were significantly higher in septic shock than in sepsis without shock. Strong correlations were noted between TNF-alpha and IL-2 levels and between IL-1 beta and IL-6 levels. Patients with high TNF-alpha and IL-2 levels also showed endotoxemia. We defined two types of septic shock from these data, i.e., endotoxin+TNF-alpha + IL-2 shock and IL-beta + IL-6 shock. In the former type, high TNF-alpha and IL-2 levels were present before the onset of shock, and shock itself was associated with endotoxemia. The second type showed simultaneous elevation of IL-1 beta and IL-6 levels at the onset of septic shock, and endotoxin was detected in some of them. These results suggest that endotoxin and extremely high levels of TNF-alpha and IL-2, or the simultaneous elevation of IL-1 beta and IL-6, are related to the onset of septic shock.
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PMID:Two types of septic shock classified by the plasma levels of cytokines and endotoxin. 129 90

Endotoxin (lipopolysaccharide [LPS])-induced cytokine release has been implicated in the pathogenesis of sepsis. Sublethal doses of LPS induce tolerance to a septic insult. This study evaluated pretreatment with interleukin 1 (IL-1) against an LPS challenge and examined its relationship to endotoxin tolerance. C3H/HeN mice (N = 100) were injected intraperitoneally with phosphate-buffered saline (control group), IL-1 (200 micrograms/kg), or LPS (1 mg/kg) for 3 days. On day 5, peritoneal macrophages were harvested and assayed for antimicrobial activity (superoxide anion production and Candida albicans phagocytosis). Serum cytokine levels and survival after an LPS challenge on day 5 were also assessed. Pretreatment with IL-1 or LPS significantly increased superoxide anion production, C albicans phagocytosis, and survival compared with pretreatment with phosphate-buffered solution. Interleukin 6 levels significantly decreased in the IL-1 and LPS groups. Peak levels of tumor necrosis factor significantly decreased only in the LPS group. Thus, pretreatment with IL-1 or low doses of LPS may exert protective effects by decreasing levels of interleukin 6 while increasing antimicrobial activity. Mice pretreated with IL-1 were protected from endotoxin despite elevated peak levels of tumor necrosis factor, suggesting a different mechanism for endotoxin tolerance than for tolerance to tumor necrosis factor.
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PMID:Interleukin 1 and its relationship to endotoxin tolerance. 131 50

This study was undertaken to evaluate the effect of a cyclooxygenase inhibitor, ibuprofen, at various time intervals in a live Escherichia coli model of canine septic shock. Group I (control) animals (n = 5) received a LD100 dose of 10(9) live E. coli per kilogram were given no further treatment. Group II animals (n = 5) received a 10 mg/kg bolus of ibuprofen 10 min prior to bacterial infusion. Group III animals (n = 5) received ibuprofen 15 min after the bacterial infusion. Statistical analysis revealed the following: Group II animals had significantly higher MABP and significantly lower levels of serum fluorescent products (superoxide radical activity), plasma thromboxane B2, prostaglandin E2, and endotoxin levels compared to Group I animals (P less than 0.05). Plasma levels of tumor necrosis factor (TNF) and interleukin-6 (IL-6) were significantly elevated (P less than 0.05) from baseline in all animals (Groups I, II, and III), but ibuprofen treatment failed to either increase or decrease these levels. This study demonstrates that ibuprofen treatment can significantly reverse the deleterious hemodynamic and metabolic effects commonly seen in live E. coli septic shock without depressing the endogenous production of TNF or IL-6. These data support the hypothesis that sepsis initiates a cascade of mediators with the cytokines TNF and IL-6 being proximal events which in turn stimulate the next level, with ibuprofen probably exerting its inhibitory effect distal to this point in the cascade.
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PMID:Ibuprofen intervention in canine septic shock: reduction of pathophysiology without decreased cytokines. 132 83

Several studies in human patients and in laboratory animals have revealed a correlation between serum interleukin (IL)-6 levels and outcome in clinical sepsis and in related animal models, respectively. In the present study, two monoclonal antibodies were used to investigate the contribution of IL-6 in the lethal action of tumor necrosis factor (TNF) and of lipopolysaccharide (LPS) in mice. We studied the potential protective properties of an anti-murine (m) IL-6 antibody and of an anti-mIL-6 receptor antibody. In controlled experiments, we observed that both monoclonal antibodies conferred a dose-dependent protection to a lethal dose of mTNF. Detailed studies with the monoclonal antibodies indicate, however, that protection was no longer observed when the mTNF dose was slightly higher than the lethal dose. Likewise, the anti-IL-6 monoclonal antibody protected against injections of LPS at a lethal-dose concentration, but here too failed to protect against higher doses of LPS. The anti-IL-6 monoclonal antibody was unable to protect against mTNF in mice sensitized by galactosamine, the corticoid receptor antagonist RU38486 or human (h) IL-1 beta. Protection did not correlate with the serum concentrations of IL-6. Finally, we demonstrate that hIL-6 injection did not change the sensitivity of mice towards mTNF. We conclude that, although IL-6 levels may be of value as a marker for the outcome in septic shock, this cytokine contributes only marginally in the pathogenesis leading to death. The small, but real, contribution of IL-6 in some situations might be due to its ability to up-regulate the level of TNF receptors.
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PMID:Limited involvement of interleukin-6 in the pathogenesis of lethal septic shock as revealed by the effect of monoclonal antibodies against interleukin-6 or its receptor in various murine models. 132

Cytokines are polypeptides which possess various biological properties affecting host defense function and response to disease. Two cytokines, interleukin-1 (IL-1) and tumor necrosis factor (TNF) induce fever, hypotension and inflammation when injected into animals or human subjects. In humans injected with either IL-1 or TNF, sleepiness, generalized myalgias and headache are commonly reported. Therefore, the production of IL-1 and TNF as a consequence of hemodialysis was hypothesized to explain, in part, the signs and symptoms of the dialysis patient. Laboratory studies confirmed that the activation of complement and the passage of microbial products from the dialysate into the blood compartment induces the synthesis of IL-1 and TNF. Although elevated production of IL-1 and TNF in the mononuclear cells and in the circulation of patients during and after hemodialysis have been reported, these levels have not been a consistent finding and are low compared to the amount of dialysis related symptoms. Recent studies, however, demonstrate that IL-1 and TNF have naturally occurring antagonists which specifically block the biological activities of these two cytokines. The IL-1 receptor antagonist blocks IL-1 binding to cells but has no IL-1 activity of itself. Soluble TNF receptors prevent TNF from binding to its cellular receptors and hence serve as anti-TNF mechanisms. These inhibitors are currently in clinical trials for sepsis where efficacy has been demonstrated; however, the IL-1 receptor antagonist (IL-1Ra) and soluble TNF receptors (sTNFR) are likely candidates for use in dialysis patients with symptomatic hypotension. Although levels of IL-1Ra and sTNFR are elevated in patients on HD, these levels reflect the host response to inflammation. It is unclear whether acute or chronic administration of IL-1Ra or sTNFR will be beneficial in treating some of the acute or chronic changes seen in dialysis patients.
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PMID:Interleukin-1 and tumor necrosis factor and their naturally occurring antagonists during hemodialysis. 132 57

Listeriosis is a not uncommon infection in humans, usually associated with immunodeficient states and with newborns. However, relatively few cases have been reported in HIV-infected patients. This scarcity of reported cases has aroused interest in the association of listeriosis and AIDS. In this paper we present a case of meningitis and septicemia caused by Listeria monocytogenes in a female patient with AIDS. A review of recent medical literature indicates that association of listeriosis and AIDS may be more common than it seems. Recent research in host-parasite interaction in listerial infection suggests an important role for tumor necrosis factor (TNF) and for integralin, a bacterial protein, in modulating listerial disease in AIDS patients. Inadequate diagnosis may be in part responsible for the scarcity of reports.
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PMID:Listeriosis and AIDS: case report and literature review. 134 13

Acute respiratory failure in pregnancy is an important cause of maternal and fetal morbidity and mortality. Causes include: ARDS, venous air embolism, beta-adrenergic tocolytic therapy, asthma, thromboembolic disease, pneumothorax, and pneumomediastinum. The most common predisposing diseases for ARDS complicating pregnancy are sepsis, pneumonia, aspiration of gastric contents, and amniotic fluid embolism. Knowledge of normal maternal-fetal physiology and determinants of fetal oxygen delivery (uterine blood flow, placental transfer, fetal circulation) can help sustain normal fetal development, usually without compromising maternal care. The increased microvascular permeability seen in ARDS is likely mediated by neutrophils, proinflammatory mediators (e.g., tumor necrosis factor, interleukin-1, arachidonic acid metabolites) and activation of the complement cascade. Treatment of respiratory failure in pregnancy is largely supportive, including mechanical ventilation, hemodynamic support, nutrition, and prophylaxis against thromboembolism. No specific therapy has as yet been proven effective for ARDS, other than treating the underlying cause. Respiratory failure from status asthmaticus is treated with vigorous bronchodilator therapy, high-dose glucocorticosteroids, magnesium sulfate, and careful ventilator management. Occasionally, more experimental therapies (e.g., isoproterenol infusion, halothane anesthesia) are indicated. Certain strategies can help prevent respiratory failure from aspiration of gastric contents, beta-adrenergic tocolytic therapy, and thromboembolic disease.
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PMID:Acute respiratory failure in pregnancy. 136 44

There is an increasing incidence of sepsis among hospitalized patients. Also, high mortality associated with sepsis and septic shock persists despite appropriate antibiotic therapy. Recent investigations have demonstrated that bacterial antigens stimulate a cascade of cellular mediators or cytokine release. In sepsis and septic shock the response of these cytokines often exceeds natural downregulation and leads to multisystem organ failure and even death in an unacceptably high number of patients. Many investigative studies have shown that tumor necrosis factor (TNF) is the prime mediator of the inflammatory response seen in sepsis and septic shock. Sepsis management in the future will include immune modulating therapy directed against the deleterious effects of cytokines, specifically TNF. This article reviews the current problem of sepsis and the evidence to support the role of TNF in sepsis. also, recent studies employing monoclonal antibodies against TNF as well as considerations for future studies are discussed.
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PMID:The role of tumor necrosis factor in sepsis. 137 Feb 62

Patients suffering from serious bacterial infection present to the hospital after early inflammatory events, such as release of tumor necrosis factor (TNF), have been initiated. The role of other cytokines, such as interleukin-8 (IL-8), a neutrophil chemoattractant and activator, in the pathophysiology of human sepsis is not well characterized, and there are only limited data on IL-6. We studied serial concentrations of TNF, IL-6 (involved in the acute-phase response), and IL-8 in plasma and leukocyte levels of mRNA for these cytokines in patients with localized and septicemic Pseudomonas pseudomallei infection on admission to the hospital and during a prolonged recovery phase (up to 30 days). Of 18 patients, 8 had detectable plasma IL-8 and all had raised plasma IL-6 concentrations. In patients who died median initial concentration of IL-8 (167 pg/ml; range, 97 to 362 pg/ml) and IL-6 (4,800 pg/ml; range, 60 to 9,245 pg/ml) in plasma were higher than those in survivors (P less than 0.008 and P = 0.007, respectively). Septic patients who survived and patients with localized disease had similar cytokine levels. Plasma IL-8 and IL-6 concentrations were elevated throughout the inpatient period of recovery. Circulating leukocytes contained mRNA for IL-8 but not for IL-6 and TNF, and they may secrete IL-8. An elevated plasma IL-6 concentration (greater than 1,000 pg/ml) had 75% mortality) was the best predictor of mortality in P. pseudomallei sepsis. Fifty percent of patients with detectable plasma IL-8 concentrations died. In contrast, plasma TNF bioactivity did not relate to outcome; 75% of patients who did never had detectable plasma TNF activity.
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PMID:Prolonged elevation of interleukin-8 and interleukin-6 concentrations in plasma and of leukocyte interleukin-8 mRNA levels during septicemic and localized Pseudomonas pseudomallei infection. 137 98


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