Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0243026 (sepsis)
 52,417 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The ability of the vascular endothelium to elaborate cytokines in response to gram-positive sepsis has received limited attention. This study examined cytokine expression by human umbilical vein endothelial cells (EC) following infection with a gram-positive bacterial pathogen, Staphylococcus aureus. S. aureus infection of EC resulted in the production of interleukin-6 (IL-6) and IL-1 beta. For IL-6, message was detected at 3 h after infection, protein was present at 24 h, and both message and protein persisted for 72 h. IL-1 beta message was detected at 12 h, IL-1 beta protein was detected at 24 h, and both persisted for 72 h. Message for colony-stimulating factor 1 remained unaltered. UV-killed S. aureus also elicited IL-1 beta and IL-6 message and protein expression at 24 and 48 h. Twenty-one clinical isolates of S. aureus were tested, and all induced IL-6 release by 48 h. However, the laboratory strain 8325-4 did not induce cytokine expression at any time point and was internalized by EC 1,000-fold less than other strains were. Internalization of latex beads by EC did not induce IL-6 gene expression. Furthermore, cytochalasin D treatment of the EC prevented IL-1 and IL-6 induction by S. aureus but not by tumor necrosis factor alpha or lipopolysaccharide. These results indicate that S. aureus is a potent inducer of IL-1 and IL-6 in EC and that internalization of S. aureus by EC is necessary for their cytokine expression. Thus, our data suggest that the vascular endothelium may play an important role in the pathogenesis of septicemia caused by gram-positive organisms.
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PMID:Internalization of Staphylococcus aureus by endothelial cells induces cytokine gene expression. 772 92

Thirteen patients (median age, 20 years) with life-threatening primary septic shock (10 meningococcal, 3 pneumococcal infections) were studied prospectively. All had a short history of sepsis (< or = 24 h) and no severe underlying disease. Two (15%) died. The logarithm of the initial plasma levels of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1 beta, IL-6, IL-1 receptor antagonist (ra), and plasminogen activator inhibitor (PAI)-1 correlated significantly with APACHE II scores (r2 = .67, .57, .68, .81, and .68, respectively). The plasma levels of endotoxin, TNF-alpha, IL-1 beta, and PAI-1 decreased toward normal levels within the first 24 h of treatment, but IL-6 and IL-1ra levels remained high until clinical recovery. On admission, the molar excess of IL-1ra to IL-1 beta was > 2000-fold in 11 of the 13 patients. Acute plasmapheresis in 11 of the 13 patients significantly increased the plasma clearance of TNF-alpha (P = .02).
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PMID:Plasma levels of cytokines in primary septic shock in humans: correlation with disease severity. 779 35

Acute necrotizing pancreatitis (ANP), which often progresses to infection, sepsis, and multisystem organ failure, runs a course remarkably similar to that seen frequently after severe burns, massive physical trauma, or major surgery. There is extensive evidence that the development of the sepsis response is mediated by immunocytes, particularly activated polymorphonuclear leukocytes (PMNLs) and their secretions (reactive oxygen species, lysosomal hydrolases, cytokines, and so on). Some years ago it was suggested that the high mortality of ANP may be related to an overaggressive immunological defense system of the host rather than to autodigestion of the gland. Recent investigations of the immunoregulatory responses following surgery or other trauma have not only furnished additional support for this concept, but also revealed some genetic factors that may critically influence the outcome of posttraumatic illness including ANP. The prognostic significance of abnormal, early polymorphonuclear leukocyte (PMNL) activation in the development of sepsis, high neutrophil expression of certain receptor molecules, low monocyte and lymphocyte expression of major histocompatibility antigen MHC-class II, and the influence of the genetically encoded TNF and IL-1 secretion on the course of the illness are discussed and related to ANP. Evidence is presented for the potential usefulness of some of these parameters in the prognosis and future treatment of ANP.
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PMID:Genetic determinants of mortality in acute necrotizing pancreatitis. 780 9

Tumour necrosis factor-alpha (TNF) and interleukin-1 beta (IL-1 beta) are the central mediators in the genesis of sepsis. The proinflammatory effects of these cytokines are counteracted in vivo by natural inhibitors. Soluble TNF receptors (sTNFR) are shed upon inflammatory stimuli such as IL-1 beta and TNF itself. Circulating TNF can be complexed by these receptors, thus preventing TNF from binding to effector cells. The binding of IL-1 beta to its receptor can be blocked by high concentrations of interleukin-1 receptor antagonist (IL-1Ra), which is produced and released upon nearly the same stimuli as IL-1 beta. This review presents some aspects of the kinetic behaviour of native sTNFR and of the production of native IL-1Ra during severe infections. It appears that in fulminant septicaemia, the plasma concentration of TNF is increased only transiently, during the very early stage of the infection. The concentration of sTNFR, in contrast, remains elevated much longer, probably due to a slower clearance. During the acute stage of severe infectious diseases, peripheral blood cells cannot be stimulated to produce IL-1 beta. The production of IL-1 Ra, in contrast, is not affected. Thus, the kinetic behaviour and regulation of TNF and IL-1 beta, is different from that of their antiinflammatory counterparts.
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PMID:Kinetics of tumour necrosis factor-alpha, soluble tumour necrosis factor receptors, interleukin 1-beta and its receptor antagonist during serious infections. 782 Dec 99

Major trauma and consecutively associated infectious complications have a major impact on the mechanisms of the specific immune response and the nonspecific inflammatory reaction. The trauma-induced host defense abnormalities become strikingly evident with the analysis of cytokine synthesis patterns. The dissociation of cell-mediated immune responses following trauma is based upon an overrepresentation of suppressor-active monocytes and inadequate T-cell help in parallel. Corresponding dysregulation of cytokine production appears within many facets. Complement, endotoxin and antigen antibody complexes cause a massive activation of monocytes with an abnormal release of essential mediators, like PGE2, IL-1, IL-6, IL-8, TGF-beta and TNF-alpha. The regulation of cytokine synthesis under stressful conditions is differentially regulated for the individual mediators, either on a transcriptional or a posttranscriptional level. In our opinion, the endogenous provisions of the organism for survival following major injury are inadequate and from this hypothesis we derive the necessity for a substantial exogenous therapeutic intervention. The primary target of modern immunotherapy must be to inhibit the conversion of a systemic inflammatory reaction in immunocompromised patients towards a status of bacterial sepsis. Different approaches appear to be feasible to avoid the development of late multiorgan failure. These interventions have to be utilized preventively in a controlled manner as early as possible after trauma has occurred, and they must effectively protect different cell systems (lymphocytes, monocytes, PMNs and endothelial cells).
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PMID:[Immune mechanisms of post-traumatic hyperinflammation and sepsis]. 782 50

Heat treatments administered prior to the onset of sepsis or endotoxemia markedly increase survival. A potential mechanism for the beneficial effect of heat could be effects on IL-1 alpha and TNF-alpha, important mediators of sepsis and endotoxemia. Administration of IL-1 or TNF prior to development of sepsis and endotoxemia increases survival; thus, prophylactic heat treatments may protect by releasing IL-1 or TNF. Paradoxically, an alternative mechanism of protection of prophylactic heat treatments could be to decrease the amount of IL-1 and TNF released during sepsis or endotoxemia. Cells pretreated with heat do not produce as much IL-1 or TNF in response to endotoxin as cells that have not been pretreated with heat. The purpose of this investigation was to determine if hyperthermia caused release of cytokines and/or blunted the rise in cytokines occurring after endotoxin. Mice were anesthetized with ketamine/xylazine and immersed in a water bath at 37.0 or 42.0 degrees C for sham or heat treatments. At 6-7 h after recovery from anesthesia and immersion, sham and heat-treated mice were injected with Escherichia coli endotoxin. Both heat-treated and sham mice had elevated plasma IL-1 alpha 2 h after anesthesia and immersion but IL-1 alpha was approximately 3-fold greater in the heated mice, 732 +/- 50 vs. 256 +/- 76 pg/ml (p < 0.01). Blood samples obtained after endotoxin revealed no difference in levels of TNF-alpha (5477 +/- 742 vs. 6514 +/- 652 pg/ml) or IL-1 alpha (546 +/- 72 vs. 603 +/- 121 pg/ml) in the sham vs. heated mice.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hyperthermia induces IL-1 alpha but does not decrease release of IL-1 alpha or TNF-alpha after endotoxin. 785 59

Macrophage inflammatory proteins 1 alpha and beta (MIP-1 alpha and beta) and macrophage inflammatory protein 2 (MIP-2) are approximately 6-8 kd, heparin binding proteins that exhibit a number of inflammatory and immunoregulatory activities. The MIP proteins are members of a superfamily of cytokines called chemokines, many of which have been shown to possess chemotactic activity for inflammatory and immune effector cells. While MIPs were originally identified as secretory products of endotoxin-stimulated mouse macrophages, these chemokines are produced by a variety of cell types including neutrophils, fibroblasts, and epithelial cells. In addition, proteins with a high degree of structural and functional homology to murine MIP-1 alpha and beta and MIP-2 have been identified in other species including humans. MIP-1 alpha and beta are chemotactic for monocytes and lymphocytes and MIP-2 is a potent chemotactic factor for neutrophils. MIPs likely also play a role in regulating hematopoiesis and stimulating production of other inflammatory mediators such as IL-1, TNF alpha, and histamine. Studies using animal models of lung injury and inflammation have implicated MIPs as important mediators of lung defense. Increased MIP expression has been observed in models of bacterial sepsis, silicosis, and oxidant-induced lung injury. Studies in humans indicate MIP-1 alpha contributes to the inflammatory cell response associated with sarcoidosis and idiopathic pulmonary fibrosis. Given the bioactivities of MIP-1 alpha and beta and MIP-2 and the recent studies demonstrating their association with lung inflammation, it is likely these chemokines play a significant role in respiratory tract defenses and may contribute to the pathogenesis of inflammatory lung disease.
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PMID:Macrophage inflammatory proteins: biology and role in pulmonary inflammation. 788 2

This study explored the relationship between cytokines (TNF, IL-1, IL-6), coagulation and fibrinolytic factors in the early stage of sepsis syndrome and the relation between these factors with the severity of inflammatory illness as measured by the Simplified Acute Physiology Score (SAPS). Twenty-one normal controls were compared to 34 patients divided into three categories ranging from uncomplicated postoperative patients, to patients with severe infectious conditions including septic shock. A major hemostatic imbalance was demonstrated with particularly marked reduction in fibrinolytic activity [drop of antithrombin III (ATIII) and protein C with an increase of plasminogen activator inhibitor (PAI-1) levels] which were directly correlated with the severity of the inflammatory state. Both ATIII and PAI-1 levels were correlated with the levels of TNF and IL-6 and the severity of illness as measured by SAPS. We established an index, ATIII/PAI-1 antigen that is significantly different among the four groups (p < 0.001) and strongly correlated with the SAPS (p < 0.001). As PAI-1 could be secreted not only by TNF activating endothelial cells but also by hepatocytes activated by insulinemia, treatment of sepsis with cytokine-specific agents might be of limited effect.
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PMID:Coagulation/fibrinolysis balance in septic shock related to cytokines and clinical state. 795 54

Sepsis is the most important cause of mortality in the Intensive Care Units. At present, sepsis is understood to be the inflammatory response of the host to infection, rather than a direct effect of microbial aggression. From the clinical standpoint, this inflammatory response is known as systemic inflammatory response syndrome (SIRS). Pathophysiologically, SIRS is characterized by the activation of several groups of cell (monocytes/macrophages, PMNs, and endothelial cells) and by the release of inflammatory mediators (cytokines and others). Tumor necrosis factor (TNF) is the first cytokine released by endotoxin action over monocyte/macrophage. TNF secretion, modulated by interferon gamma (IFN gamma) and interleukin 10 (IL-10), is followed by release of other cytokines such as interleukins (IL) (IL-1, IL-6 and IL-8). These mediators are able to act over hemostasis activating the extrinsic pathway through tissue factor expression. The action of the mediators over endothelial cells induces an increase in plasminogen activator inhibitor type 1 (PAI-1) levels with inhibition of fibrinolysis. Both coagulation activation and fibrinolysis blockade result in fibrin deposit in the microvascular system. The complexity of the mechanisms implicated in systemic inflammatory response make a general rule so difficult to establish, because patient response is highly individualized and it is not possible to know which moment of this dynamic process is being analyzed.
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PMID:Inflammatory mediators and their influence on haemostasis. 795 61

Mild infection or sublethal dose of endotoxin elicits a brief elevation of GH and PRL in the serum. These hormones have proinflammatory and immunostimulatory effect. In severe trauma, sepsis and shock, GH and PRL are suppressed, whereas glucocorticoids and catecholamines are elevated. Under these conditions an acute phase response is initiated by tissue derived (cytokine) hormones, namely IL-1, IL-6, TNF alpha, and several others, which elicit a neuroendocrine response and initiate major metabolic alterations. There is fever and catabolism prevails, whereas the synthesis of acute phase proteins in the liver, cell proliferation in the bone marrow, and protein synthesis by leukocytes is elevated. This is an emergency reaction to save the organism after the local immune/inflammatory response has failed to contain and eliminate the infectious agent. During sepsis and endotoxin shock the systemic activation of the complement system and of leukocytes releasing enzymes and highly toxic cytokines seriously threaten survival. Glucocorticoids suppress proinflammatory cytokine production and potentiate the secretion of acute phase proteins. Some of these proteins, such as C reactive protein, or LPS binding protein, are designed to combine with microorganisms and trigger their destruction by the activation of complement system and of phagocytes. The increased production of some complement components also helps host resistance. The rise in serum fibrinogen promotes blood clotting which can serve to isolate the invading agent by triggering thrombosis in infected tissues. A number of enzyme inhibitors are produced as acute phase proteins, which are likely to serve to curb the nonspecific damage inflicted by enzymes released from activated phagocytes and from damaged cells into the circulation during sepsis and shock. Catecholamines are also elevated, which serve to inhibit inflammatory responses and to promote, even initiate, the acute phase response. If the acute phase reaction fails to protect the host, shock will develop. Patients with subclinical adrenal insufficiency succumb to septic shock almost invariably if glucocorticoid therapy is not given. However, glucocorticoid treatment of septic patients with normal adrenal function has not been helpful. The use of antibiotics to control infection did not lead to spectacular success either because of the emergence of resistant bacterial strains or the enhanced release of endotoxin by this therapy. The new approaches to prevent and treat septic shock involve the use of antibodies capable of neutralizing LPS and of cytokines and the inhibition of cytokine action by antagonist agents.
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PMID:Neuroendocrine defence in endotoxin shock (a review). 797 6


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