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)

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

In patients with disseminated intravascular coagulation (DIC), hyperfibrinolysis was observed in patients with leukaemia, but hypofibrinolysis was seen in those with sepsis. Although the plasma tissue plasminogen activator (t-PA) level was higher in patients with DIC than in those without DIC, there was no significant difference in t-PA level between the patients with leukaemia and sepsis. Hyperfibrinolysis might not be caused by t-PA derived from leukaemic cells, although the PA antigen level in leukaemic cell homogenates was significantly higher in patients with DIC than in those without DIC. The activation of t-PA by leukaemic cell homogenates in the absence of bromocyan fibrinogen fragments suggested that leukaemic cell homogenates had t-PA stimulator activity. The t-PA stimulator activity was high in both acute myeloblastic leukaemia (AML) and acute lymphoblastic leukaemia (ALL), especially in DIC, but this activity was not detected in chronic myelocytic leukaemia (CML) or normal cells. Since fibrinogen and soluble fibrin monomer complex levels in leukaemic cells were also high in patients with DIC, fibrinogen degradation products might be the major t-PA stimulator in leukaemic cells. This might be one of the causes of hyperfibrinolysis in leukaemia.
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PMID:Stimulation of tissue type plasminogen activator by leukaemic cell homogenates. 821 56

Aiming to know the coagulation disorders that occur in patients with sepsis, a retrospective study of 75 such patients hospitalized in an Intensive Care Unit was performed. The coagulation profile requested by the attending physician, that included platelet count, prothrombin time, partial thromboplastin time, thrombin time, protamine sulphate test, fibrinogen and euglobin lysis time, was analyzed. Fourteen patients that were receiving prophylactic subcutaneous heparin were excluded from further analysis. Of the 61 remaining patients, 23 had hemorrhagic manifestations and 94.4% of these had multiple alterations in coagulation parameters. Eighty one percent of patients had abnormal prothrombin time and 73% thrombocytopenia. Isolated alterations were infrequent and consisted in thrombocytopenia (3.7%) and fibrinogen elevation (1.9%). Fifty two percent of patients had shock and they had significantly lower platelet counts and higher prothrombin and thrombin times than patients without hemodynamic disturbances. Global mortality was 63.9%. No relation between coagulation disturbances and mortality was observed. Likewise, no differences in mortality between patients with or without shock was observed. It is concluded that coagulation is frequently disturbed in patients with sepsis, even without clinical hemorrhagic symptoms, that these abnormalities are more marked in patients in shock and that 53% of these are consistent with intravascular coagulation.
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PMID:[Changes in coagulation in patients with sepsis]. 827 35

Disseminated intravascular coagulation (DIC) is a common complication in sepsis, and may result from endotoxin-induced exposure of tissue factor on the surface of monocytes and endothelial cells. Tissue factor pathway inhibitor (TFPI) is a factor Xa-dependent feedback inhibitor of the tissue factor-factor VIIa complex. In the present study the effect on DIC of a two-domain TFPI analogue (2D-TFPI), consisting of the first two Kunitz domains of TFPI but lacking the third domain, was tested. DIC was induced in rabbits by two intravenous bolus injections of endotoxin from Escherichia coli (10 and 50 micrograms/kg) 24 h apart. Simultaneously with the last endotoxin injection an infusion of 2D-TFPI (0, 0.3, 1.0 or 3.0 mg/kg/h) was given. Blood samples were obtained at 0 h, 24 h and 31 h. At 31 h the animals were sacrificed and the kidneys were submitted to histological examination. The degree of fibrin deposition in glomeruli was scored blindly using an arbitrary scale from 0 to 3. Between 24 and 31 h the group receiving endotoxin alone showed a significant decrease in platelet count (65%), plasma fibrinogen (41%), antithrombin III (25%), and factor VIII (63%), and a significant prolongation of the aPTT (14%). Furthermore, massive fibrin deposition was detected in the renal glomeruli at 31 h. Infusions of 2D-TFPI inhibited all the endotoxin-induced changes in a dose-dependent manner. In conclusion, the data demonstrate that inhibition of the TF/FVIIa complex by infusion of 2D-TFPI significantly counteracts endotoxin-induced coagulopathy in rabbits, and might thus be an attractive drug for treatment of endotoxin-induced DIC in humans.
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PMID:The effect of two-domain tissue factor pathway inhibitor on endotoxin-induced disseminated intravascular coagulation in rabbits. 829 19

There is no satisfactory assay procedure of PAF in human whole blood in terms of sensitivity, reproducibility and simplicity. This is due to coexisting lipids from plasma and cellular membranes which inhibit measurement of PAF in various assay procedures, including bioassay. In the present study, an attempt was made to eliminate these interfering lipid inhibitors from blood samples. Lipids in human whole blood were extracted according to the method of Bligh & Dyer and the organic layer was dried under a stream of nitrogen. Then, the dried organic layer was dissolved in diethyl-ether and the solution was kept at -20 degrees C which was then centrifuged. The resulting supernatant was then applied to an anion-exchange column and the PAF fraction was obtained by step-wise gradient elution. The fraction was further purified by normal phase HPLC. Then PAF in the final sample was determined by sensitive bioassay using rabbit platelets containing fibrinogen and epinephrine. The recovery rate of PAF throughout this procedure was constant and satisfactory (37.4 +/- 9.7%), which was confirmed using [3H]-PAF. The lower limit of the present assay was estimated to be 5pg in 1 ml of blood and it was sensitive enough to detect PAF in blood samples from healthy volunteers and patients with sepsis or liver cirrhosis. Furthermore, attempts were made to compare the sensitivity and the recovery of our method with these of a commercially available radioimmunoassay (RIA) kit for PAF. However, it was not possible to detect any amount of authentic PAF added to whole blood.
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PMID:A new method of purification and sensitive bioassay of platelet-activating factor (PAF) in human whole blood. 829 90

The possible involvement of platelet activating factor (PAF) in the pathogenesis of endotoxin-induced disseminated intravascular coagulation (DIC) was investigated in rats using a novel potent PAF antagonist, TCV-309. TCV-309 (> 1 mg/kg, i.v.) showed beneficial effects in rats with experimental DIC induced by a 4-hour sustained infusion of endotoxin (1 mg/kg) in a dose-dependent manner. TCV-309 (1 mg/kg) significantly ameliorated the decrease in platelet count and plasma fibrinogen, the prolongation of prothrombin time (PT) and activated partial thromboplastin time (APTT) and the increase in fibrin and fibrinogen degradation products (FDP) and inhibited glomerular fibrin deposition. Furthermore, plasma tissue factor (TF) activity was greatly increased in the DIC rats, and this was also significantly decreased by TCV-309 (1 mg/kg). TCV-309 (1 mg/kg) did not affect these parameters in normal rats. A 4-hour sustained infusion of PAF (60 micrograms/kg) caused mild but significant changes in some DIC parameters such as PT, fibrinogen and FDP concentration and increased the plasma TF activity. TCV-309 (1 mg/kg) inhibited all these PAF-induced changes. TCV-309 (0.1 mM) itself had no direct in vitro effects on the blood coagulation system including TF activity. These results strongly suggest that PAF plays a role in the pathogenesis of endotoxin-induced DIC via the generation of TF. Prophylactic use of PAF antagonists may therefore be useful for the treatment of DIC with sepsis.
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PMID:Inhibitory effect of TCV-309, a novel platelet activating factor (PAF) antagonist, on endotoxin-induced disseminated intravascular coagulation in rats: possible role of PAF in tissue factor generation. 833 59

Experimental gram-negative sepsis was induced in the rat by Klebsiella pneumoniae. Although bacteria are susceptible to the treatment with the antibiotic Tobramycin, DIC could not be prevented. DIC was manifested by a leuko- and thrombocytopenia, decreases in fibrinogen and AT III and an increase of the aPTT. In this model the therapeutic treatment with human AT III was evaluated. To determine the optimal concentration of AT III a prestudy in a LPS induced DIC in the rat was performed. It was shown that a bolus i.v. injection of 500 U/kg improved survival and DIC, and was thus chosen for the Klebsiella sepsis model. The infectious load was adjusted to yield a mortality rate of 90-100% in the untreated Klebsiella group and a reduction to about 40-50% of the mortality rate by Tobramycin. It was found that AT III reduced mortality in the Klebsiella induced sepsis not only when given prophylactically but was effective even when administrated in a late stage of the DIC, i.e. 3 or 5 h post infection.
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PMID:Reduction of mortality with antithrombin III in septicemic rats: a study of Klebsiella pneumoniae induced sepsis. 845 37

Trauma favors the development of adult respiratory distress syndrome (ARDS). Adherence of polymorphonuclear leukocytes (PMN) to endothelial cells (EC) with subsequent EC damage by the respiratory burst products and proteases of the PMN is thought to be one of the basic mechanisms in the pathogenesis of ARDS. Recent studies have shown that there might also be PMN-independent mechanisms of EC damage. It would speak for PMN-independent EC damage if in the state of risk for this damage factors were found which decrease PMN activity or if EC damage appeared without PMN. Because in trauma and sepsis pathologic coagulation with high levels of fibrinogen degradation products (FDP) is often diagnosed, we investigated whether FDP-D and FDP-E might influence PMN adherence to EC. We also investigated whether serum of traumatized patients might provoke EC damage in a PMN-independent system in vitro. To achieve this we evaluated the viability of EC using a fluorescence staining method. We found that both FDP-D and FDP-E decreased PMN adherence to human EC significantly (p < 0.01) at a concentration of 50 micrograms/ml. Furthermore we found that EC membrane integrity can be disturbed by serum of trauma patients. These results suggest that in trauma also PMN-independent mechanisms are important for EC damage.
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PMID:In vitro studies on PMN-independent endothelial cell damage in trauma: decrease of PMN-endothelial cell adherence by fibrinogen degradation products and disturbance of endothelial cell membrane integrity by trauma serum. 848 13

Although the low molecular weight degradation products of fibrinogen (FgDP) and fibrin (FbDP) are known to inhibit lymphocyte blastogenesis, the effect of purified macro-molecular FgDP and FbDP (molecular weight, 90 to 200 Kd) is unclear. We have examined the effect of these latter FgDP and FbDP and find that products that contain the D domain inhibit lymphocyte proliferation in response to T-cell mitogens, allogeneic mononuclear leukocytes, and anti-CD3 in vitro. Plasmic digestion of D1 in the absence of calcium with removal of the C-terminal end of the gamma chain or disruption of the gamma-gamma C-terminal cross-link site of D-dimer (DD) by puffadder venom (PAV-D) abrogates their inhibitory potential. Prior incubation of monocytes with DD or D1 inhibits subsequent lymphocyte transformation. Binding studies with radiolabeled DD and PAV-D confirm that monocytes interact only with DD. This specific binding may be competitively inhibited by monoclonal antibodies to CD11b/CD18 or by peptide analogues of the C-terminal gamma chain of fibrinogen that mimic the adhesion recognition site of integrins. We postulate that DD and D1 bind to CD11b/CD18 on adherent monocytes and modulate lymphocyte activation. These products are typically present in the plasma of patients with disseminated intravascular coagulation with sepsis and could therefore influence inflammatory processes in vivo.
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PMID:Fibrin and fibrinogen degradation products with an intact D-domain C-terminal gamma chain inhibit an early step in accessory cell-dependent lymphocyte mitogenesis. 849 35

This study was designed to test the hypothesis that tissue factor pathway inhibitor (TFPI) plays a significant role in vivo in regulating coagulation that results from exposure of blood to tissue factor after vascular injury as in the case of gram negative sepsis. Highly purified recombinant TFPI (6 mg/kg) was administered either 30 min or 4 h after the start of a lethal intravenous Escherichia coli infusion in baboons. Early posttreatment of TFPI resulted in (a) permanent seven-day survivors (5/5) with significant improvement in quality of life, while the mean survival time for the controls (5/5) was 39.9 h (no survivors); and (b) significant attenuations of the coagulation response and various measures of cell injury, with significant reductions in pathology observed in E. coli sepsis target organs, including kidneys, adrenals, and lungs. TFPI administration did not affect the reduction in mean systemic arterial pressure, the increases in respiration and heart rate, or temperature changes associated with the bacterial infusion. TFPI treated E. coli infected baboons had significantly lower IL-6 levels than their phosphate buffered saline-treated controls, however tumor necrosis factor levels were similarly elevated in both groups. In contrast to the earlier 30-min treatment, the administration of TFPI at 4 h, i.e., 240 min, after the start of bacterial infusion resulted in prolongation of survival time, with 40% survival rate (2/5) and some attenuation of the coagulopathic response, especially in animals in which fibrinogen levels were above 10% of normal at the time of TFPI administration. Results provide evidence for the significance of tissue factor and tissue factor pathway inhibitor in bacterial sepsis, and suggest a role for blood coagulation in the regulation of the inflammatory response.
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PMID:Tissue factor pathway inhibitor reduces mortality from Escherichia coli septic shock. 851 93


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