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

The hypotension in septicemia is believed to be mediated by the combined action of many mediators including cytokines, prostaglandins, and complement components. To evaluate the contribution of the contact/kinin-forming system to hypotension, the authors used an established experimental baboon model of bacteremia in which two concentrations of Escherichia Coli (E. coli) were used to produce lethal and nonlethal hypotension. The lethal group (n = 5) developed irreversible hypotension that significantly correlated with the decline in levels of high molecular weight kininogen (HK) and an increase in alpha 2 macroglobulin-kallikrein complexes (alpha 2M-kal). The nonlethal group (n = 9) experienced reversible hypotension, a less striking decline in HK, and only slight elevation in alpha 2M-kal. No significant changes were found in levels of factor XII, prekallikrein, and factor XI in either group. A significant change in the contact system, which reflects the fatal outcome, is the rise in alpha 2M-kal. This study suggests that irreversible hypotension correlates with prolonged activation of the contact system.
 ...
PMID:Activation of the contact system in lethal hypotensive bacteremia in a baboon model. 137 71

Alpha 2-macroglobulin (alpha 2 M) in vitro inhibits numerous proteinases that are generated during inflammatory reactions and therefore, probably plays an important role in diseases such as sepsis. To monitor the state of alpha 2 M in sepsis, we developed novel assays for functional and inactive alpha 2M. Functional alpha 2M in plasma was measured by quantitating the binding of alpha 2M to solid-phase trypsin. Inactive alpha 2M (i alpha 2M) was assessed with a monoclonal antibody, mcAb M1, that specifically reacts with a neodeterminant exposed on i alpha 2M. This mcAb in combination with chromogenic substrates was used to detect alpha 2M-proteinase complexes. Functional alpha 2M was reduced in plasma from 48 patients with clinical sepsis compared to healthy controls (p less than 0.0001). Levels of functional alpha 2M on admission and the lowest levels encountered in 23 patients with shock were lower than in 25 normotensive patients (p = 0.023 and p = 0.009, respectively). Increased levels of i alpha 2M (greater than 30 nM) at least on one occasion were found in only 4 of the 48 patients, being not different in hypotensive compared with normotensive patients, and not in patients who died compared with those who survived. Levels of functional alpha 2M correlated significantly with levels of factor XII and prekallikrein suggesting that decreases in alpha 2M at least in part were due to contact activation. Indeed, in two patients with increased i alpha 2M, complexes between alpha 2M and kallikrein were demonstrated in addition to plasmin- and thrombin-alpha 2M complexes.
 ...
PMID:Quantification of functional and inactivated alpha 2-macroglobulin in sepsis. 170 20

Patients treated with high doses of interleukin-2 (IL-2) because of cancer, develop hemodynamic and vasopermeability changes, that resemble those observed in sepsis. These patients thus provide a unique opportunity to study the early events in the development of septic shock. We analysed the changes that occurred in the contact system of coagulation in plasma from 4 patients, who together received seven 12-day cycles of high doses of IL-2. Levels of factor XII and prekallikrein during the cycles progressively fell to 50 and 30% of their initial levels, respectively, whereas significant increases in plasma factor XIIa- and kallikrein-C1-inhibitor complexes were not observed (in 3 out of 211 samples slightly increased levels of both complexes were found). The reductions in factor XII and prekallikrein were only in part due to protein leakage, since levels were still significantly lower, i.e., 80 and 50%, respectively, when corrected for albumin decreases. Levels of high molecular weight kininogen (HMWK) also decreased during IL-2 therapy, however, this decrease paralleled that of albumin. SDS-PAGE analysis of plasma HMWK did not reveal increased cleavage of this protein. The reduction of factor XII and prekallikrein, corrected for protein leakage, significantly correlated with albumin levels and inversely with daily cumulative weight gain in the patients. Thus, we demonstrate that factor XII and prekallikrein decrease during IL-2 therapy. As these decreases, already observed after 1 day treatment, were disproportional to that of albumin, a negative acute phase reactant, and correlated with signs of the vascular leak syndrome, we favor the explanation that they reflected activation rather than a decreased synthesis of the contact system proteins.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Studies on the contact system of coagulation during therapy with high doses of recombinant IL-2: implications for septic shock. 187 10

Tumor necrosis factor has been implicated in the activation of blood coagulation in septicemia, a condition commonly associated with intravascular coagulation and disturbances of hemostasis. To evaluate the early dynamics and the route of the in vivo coagulative response to tumor necrosis factor, we performed a controlled study in six healthy men, monitoring the activation of the common and intrinsic pathways of coagulation with highly sensitive and specific radioimmunoassays. Recombinant human tumor necrosis factor, administered as an intravenous bolus injection (50 micrograms per square meter of body-surface area), induced an early and short-lived rise in circulating levels of the activation peptide of factor X, reaching maximal values after 30 to 45 minutes (mean +/- SEM increase after 45 minutes, 34.2 +/- 18.2 percent; tumor necrosis factor vs. saline, P = 0.015). This was followed by a gradual and prolonged increase in the plasma concentration of the prothrombin fragment F1+2, peaking after four to five hours (mean increase after five hours, 348.0 +/- 144.8 percent; tumor necrosis factor vs. saline, P less than 0.0001). These findings signify the formation of factor Xa (activated factor X) and the activation of prothrombin. Activation of the intrinsic pathway could not be detected by a series of measurements of the plasma levels of factor XII, prekallikrein, factor XIIa-C1 inhibitor complexes, kallikrein-C1 inhibitor complexes, and the activation peptide of factor IX. The delay between the maximal activation of factor X and that of prothrombin amounted to several hours, indicating that neutralization of factor Xa activity was slow. We conclude that a single injection of tumor necrosis factor elicits a rapid and sustained activation of the common pathway of coagulation, probably induced through the extrinsic route. Our results suggest that tumor necrosis factor could play an important part in the early activation of the hemostatic mechanism in septicemia.
 ...
PMID:Activation of coagulation after administration of tumor necrosis factor to normal subjects. 221 25

Previously we studied levels of the cytokine IL-6 and activation of the complement and contact system and of neutrophils in a group of 48 patients with sepsis. Some of these inflammatory parameters appeared to be associated with a poor prognosis. Here we report on the relationships of C4a and C3a (complement activation products), of factor XII and prekallikrein (contact system proteins), of elastase (a protease released by activated neutrophils) and of the cytokine IL-6 to hemodynamic and biochemical parameters measured in those 48 patients at the time of admission to the Intensive Care Unit. No significant correlations between any inflammatory parameter and either systemic vascular resistance or cardiac index were found. Mean arterial pressure significantly correlated with both factor XII and prekallikrein levels. Lactate correlated with C3a and C4a, with elastase, and in particular, with IL-6, whereas it did not correlate with either factor XII or prekallikrein. Platelet numbers inversely correlated with both C3a and C4a, as well as with elastase and IL-6, whereas they positively correlated with factor XII and prekallikrein. Based on these findings we propose a model for the interplay of these inflammatory mediators in the pathogenesis of sepsis. This model takes into consideration the occurrence of capillary leakage, shock, disseminated intravascular coagulation, thrombocytopenia and of acute phase reactions in sepsis.
 ...
PMID:A model for the interplay of inflammatory mediators in sepsis--a study in 48 patients. 228 88

High molecular weight kininogen (HMWK) is a multifunctional protein that is a parent molecule for bradykinin, a cofactor for coagulation, and an inhibitor of cysteine proteases. On immunoblot, nonreduced plasma HMWK is usually two bands at 140 kd and 120 kd; reduced plasma HMWK is a single band at 120 kd. In both concentration-dependent and time-dependent experiments kaolin-activated normal plasma HMWK becomes cleaved in an ordered sequence. When nonreduced, HMWK on immunoblot in kaolin-activated plasma changes in size from a 140 kd band through a 120 kd intermediate to result in a stable 100 kd protein. When reduced, HMWK on immunoblot in kaolin-activated plasma changes from a single 120 kd band through a 56 kd intermediate to result in a stable 46 kd protein. A similar sequence of cleavage of plasma HMWK occurs when the soluble activator dextran sulfate is used to stimulate the system. Cleavage of plasma HMWK after kaolin activation occurs similarly in factor XI-deficient plasma as in normal plasma but is decreased in prekallikrein-deficient plasma. Prolonged kaolin activation of prekallikrein-deficient plasma results in HMWK cleavage to bands below 120 kd. No band of plasma HMWK below 120 kd appears in prolonged kaolin-activated factor XII-deficient plasma. In some patients with sepsis, detectable cleavage of plasma HMWK to bands below 120 kd may not be seen, even though the patient has other evidence for contact system activation. In conclusion, these studies indicate that certain cleaved patterns of plasma HMWK on immunoblot indicate prior activation of the contact system. However, the absence of these cleaved forms of plasma HMWK in a single plasma does not exclude the occurrence of contact activation.
 ...
PMID:Structural changes of plasma high molecular weight kininogen after in vitro activation and in sepsis. 245 60

Fatal multiple organ failure after severe infection may be related to an early activation of protease cascade systems. This study aimed to relate changes in coagulation, fibrinolysis, and kallikrein to shock and outcome. Of 53 patients with severe infection, 30 did not develop shock, 12 survived septic shock, and 11 died from organ failure after septic shock. No patient had overt disseminated intravascular coagulation. We measured 17 components of the coagulation/fibrinolysis/kallikrein pathways on admission and on the next 2 days. High values for fibrinogen, factor VIII:C, von Willebrand factor antigen, and D-dimer were seen in all patients; factor XII, prekallikrein, factor VII, antithrombin, protein C, and fibronectin were low. The patients thus appeared to be hypercoagulable. These disturbances were more pronounced in septic shock survivors, who also had low plasminogen and antiplasmin, indicating ongoing fibrinolysis. Nonsurvivors of sepsis were distinguished mainly by high plasminogen activator inhibitor values; this suggests an impaired functional fibrinolysis in fatal sepsis, with possible therapeutic implications. Cryoprecipitate infusion increased the fibronectin concentration, but did not influence the other factors studied.
 ...
PMID:Coagulation, fibrinolysis, and kallikrein systems in sepsis: relation to outcome. 250 62

Considerable evidence indicates that activation of the contact system of intrinsic coagulation plays a role in the pathogenesis of septic shock. To monitor contact activation in patients with sepsis, we developed highly sensitive radioimmunoassays (RIAs) for factor XIIa-Cl(-)-inhibitor (Cl(-)-Inh) and kallikrein-Cl(-)-Inh complexes using a monoclonal antibody (MoAb Kok 12) that binds to a neodeterminant exposed on both complexed and cleaved Cl(-)-Inh. Plasma samples were serially collected from 48 patients admitted to the intensive care unit because of severe sepsis. Forty percent of patients on at least one occasion had increased levels of plasma factor XIIa-Cl(-)-Inh (greater than 5 x 10(-4) U/mL) and kallikrein-Cl(-)-Inh (greater than 25 x 10(-4) U/mL), that correlated at a molar ratio of approximately 1:3. Levels of factor XII antigen in plasma and both the highest as well as the levels on admission of plasma factor XIIa-Cl(-)-Inh in 23 patients with septic shock were lower than in 25 normotensive patients (P = .015: factor XII on admission; P = .04: highest factor XIIa-Cl(-)-Inh; P = .01: factor XIIa-Cl(-)-Inh on admission). No significant differences in plasma kallikrein-Cl(-)-Inh or prekallikrein antigen were found between these patients' groups. Elevated Cl(-)-Inh complex levels were measured less frequently in serial samples from patients with septic shock than in those from patients without shock (P less than .0001). Based on these results, we conclude that plasma Cl(-)-Inh complex levels during sepsis may not properly reflect the extent of contact activation.
 ...
PMID:Quantification of plasma factor XIIa-Cl(-)-inhibitor and kallikrein-Cl(-)-inhibitor complexes in sepsis. 326 90

Adult respiratory distress syndrome (ARDS) is a complex pulmonary clinicopathologic condition associated with pulmonary endothelial injury and blood coagulation activation. In patients with ARDS from all causes, factor VII levels were significantly reduced. Patients with ARDS caused by sepsis had more evidence of intravascular coagulation and fibrinolysis than did patients with trauma-related ARDS by having significantly (p less than or equal to 0.05) increased prothrombin times, activated partial thromboplastin times, and fibrin degradation products, and decreased antithrombin III concentration. We sought to determine whether the proteins of the contact system of plasma proteolysis (factor XII, prekallikrein, high molecular weight kininogen, and C1 inhibitor) were also activated after acute lung injury. Patients with ARDS caused by either trauma or sepsis had significantly (p less than or equal to 0.01) reduced factor XII levels, high molecular weight kininogen functional activity, prekallikrein activity, and prekallikrein antigen levels compared with controls. In both the sepsis-related and trauma-related ARDS groups, C1 inhibitor activity was significantly reduced but C1 inhibitor antigen levels were significantly elevated from control. These findings showed that the proteins of the contact system were more extensively activated in ARDS than were the proteins that contribute to later reactions in intravascular coagulation and fibrinolysis. Activation of the contact system proteins could be the result of endothelial injury occurring as part of ARDS. Intravascular coagulation and fibrinolysis in patients with ARDS also arise from components independent from contact system activation.
 ...
PMID:Activation of the contact system of plasma proteolysis in the adult respiratory distress syndrome. 339 29

Posttraumatic acute cholecystitis is an often unrecognized and potentially fatal complication seen among patients hospitalized for trauma, and differs in etiology from cholecystitis which develops de novo. The cause, although not yet clearly defined, is believed to be related to bile stasis, ischemia, bacterial infection, sepsis, the activation of factor XII, and the Shwarzman reaction. A case is described in which a 53-year-old man with pelvic fractures developed acute acalculous cholecystitis and died of multiple organ failure 3 weeks following cholecystectomy. The histopathological findings are also reported; these are most likely attributed to the Shwarzman reaction or the activation of the factor XII pathways. There has been a tendency to regard posttraumatic acute acalculous cholecystitis as induced by trauma, and calculous as mere coincidence. We believe, however, that it is not calculous but histopathological findings that determine whether acute cholecystitis following trauma was more than coincidence or just mere coincidence. Although progress in clinical care has improved the chances of survival of severely traumatized patients, posttraumatic acute cholecystitis has been increasing in frequency. We cannot be careful enough in judging the relationship of this fatal complication to the initial trauma.
 ...
PMID:Posttraumatic acute cholecystitis. Relationship to the initial trauma. 360 14


1 2 3 4 Next >>