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)

The levels of protein C (PC) and other coagulation factors were monitored during endotoxin-induced disseminated intravascular coagulation (DIC) in the dog. Initial evaluation of the effectiveness of intradermal administration of bolus endotoxin quantities into the dog, demonstrated induction of DIC in the canine, without the severe side effects associated with bacterial sepsis. Quantitative determination of canine plasma protein C levels were performed using a multiple step amidolytic assay, that included a specific precipitation of the vitamin K-dependent proteins from citrated plasma, followed by thrombin activation (and neutralization) and subsequent measurement of the activated protein C (APC) by chromogen hydrolysis. This investigation demonstrated, that over a twenty-four hour interval, intradermal administration of endotoxin produces a gradual decrease in the PC activity levels, concomitant with a significant reduction in the Factor V, Factor VIII and fibrinogen levels and platelet count, and a prolongation of the Prothrombin Time and Partial Thromboplastin Time. During the first 6 hours, protein C levels fell below the pre-levels and remained significantly lower in the surviving dogs. Thus, this endotoxin-induced DIC animal model permits evaluation of various hemostatic parameters, yet diminishes the severe clinical findings associated with DIC.
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PMID:Protein C activity levels in endotoxin-induced disseminated intravascular coagulation in a dog model. 278 30

In order to determine the effect of bacterial proteinases on activation of the protein C system, a negative regulator of blood coagulation, two arginine-specific cysteine proteinases (gingipains R) from Porphyromonas gingivalis, a causative bacterium of adult periodontitis, were examined. Each enzyme activated human protein C in a dose- and incubation time-dependent manner. Interestingly, the form of enzyme being composed of a non-covalent complex containing both catalytic and adhesion domains (RgpA) produced activated protein C 14-fold more efficiently than RgpB which contained the catalytic domain alone. The kcat/Km value of RgpA was 18-fold higher than that of RgpB and comparable to that of the thrombin-thrombomodulin complex, the physiological activator of protein C. RgpA catalyzed protein C activation was augmented 1.4-fold by phospholipids, ubiquitous cell membrane components. Furthermore, RgpA, but not RgpB, could activate protein C in plasma and this resulted in a decrease of the protein C concentration in plasma, which is often observed in patients with sepsis during the development of disseminated intravascular coagulation (DIC). These data indicate that RgpA is a more potent activator of protein C than RgpB and suggest that only the former enzyme can cause protein C activation in vivo. The present study further suggests that bacterial proteinases may possibly contribute to the consumption of plasma protein C which predisposes to DIC and/or promotes a thrombotic tendency towards DIC in sepsis.
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PMID:Activation of protein C by arginine-specific cysteine proteinases (gingipains-R) from Porphyromonas gingivalis. 1006 39

Disseminated intravascular coagulation as associated to sepsis contributes to the development of clinical multiple organ failure by extensive thrombosis in microcirculation vessels. This condition commonly manifests itself in severe meningococcal sepsis. On the skin, its clinical manifestation is extensive purpura with necrotic lesions that usually progress to serious distal ischemia and may call for amputation. A common denominator in these events regarding hemostasis is a depletion of so-called natural anticoagulant proteins, particularly protein C. According to clinical observations replacement therapy with human plasma-derived protein C concentrates has been associated with significantly improved clinical outcome in patients with meningococcal sepsis and fulminant purpura. This paper reports a case of acquired protein C deficiency in a girl with meningococcal sepsis, fulminant purpura, disseminated intravascular coagulation, and septic shock. Fresh plasma therapy was intended to increase consumption coagulopathy-depleted coagulation factors and to provide small amounts of protein C. The inability to restore protein C concentrations above 30%, and the presence of severe thrombopenia in the setting of disseminated intravascular coagulation led to the onset of replacement therapy using a human protein C concentrate (Ceprotin), which increased plasma protein C concentrations and contributed to revert the existing hypercoagulability status. Finally, evidence available in the literature regarding fulminant meningococcal sepsis management using human protein C concentrates and recombinant activated protein C is discussed.
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PMID:[Replacement therapy with protein C for meningococcal sepsis and fulminant purpura in pediatric patients]. 1510 5

Decreased circulating protein C is a marker of a prothrombotic state that has been associated with poor clinical outcomes in sepsis. However, protein C has not been measured in patients with acute lung injury and acute respiratory distress syndrome (ALI/ARDS). In this study, we measured circulating and intra-alveolar concentrations of protein C in 45 patients with ALI/ARDS from septic and nonseptic causes. Plasma protein C levels were lower in ALI/ARDS compared with normal controls. Lower levels of plasma protein C were associated with worse clinical outcomes, including death, fewer ventilator-free days, and more nonpulmonary organ failures, even when only patients without sepsis were analyzed. In summary, the protein C system is markedly disrupted in patients with ALI/ARDS from both septic and nonseptic causes. The protein C system may be a therapeutic target in patients with ALI/ARDS.
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PMID:Plasma protein C levels in patients with acute lung injury: prognostic significance. 1511 23

The coagulation disturbance, typical of septic conditions, is associated to a reduction of clotting factors in plasma with an "acquired" deficiency (from consumption) of protein C. As observed with "purpura fulminans" in neonates affected by congenital protein C deficiency, administration of protein C concentrate has proved to reduce thrombotic manifestations and to improve morbidity and mortality of children with septic shock. The Protein C concentrate is presently utilized as a therapy for patients with a congenital deficiency of protein C and several papers in the literature support the efficacy of protein C concentrate in the treatment of children with meningococcus septicemia, with the aim of correcting the acquired protein C deficiency often seen in septic conditions and shown to be strongly correlated to a higher morbidity and mortality. Protein C, given as a plasma concentrate, can exert its therapeutic actions only after activation once in the blood stream: clinical trials with the use of protein C concentrate failed to show any increased risk of bleeding or related disorders. At our PICU 8 children, with sepsis, septic shock and purpura have been treated with protein C concentrate (Ceprotin); because the plasma protein C level was lower than the normal range (mean value 0.32 IU/ml, range 0.11-0.6 IU/ml). Six children have shown a rapid response to all therapeutic efforts and survived without sequelae and two are died. No adverse reaction was observed during and after Ceprotin administration to all patients.
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PMID:[Use of protein C concentrate in critical conditions: clinical experience in pediatric patients with sepsis]. 1518 16

Severe sepsis is a high prevalent disease at Intensive Care Units with no specific treatment till recently. Several clinical trials show low serum levels of activated protein C in this kind of patients. Recently, drotrecogin alfa (activated), a recombinant human activated protein C, has been approved in Spain for severe sepsis treatment in addition to the best patient care. Protein C (activated) has antithrombotic, profibrinolitic an antiinflamatory properties. So far, Prowess (phase 3 trial) is the most important clinical trial conducted with drotrecogin alfa (activated) at the moment. It demonstrates not only its efficacy and safety, but also a 19.4% reduction in the relative risk of death. Nevertheless, it is difficult to decide which patients would be candidate for this new therapy due to its lack of experience, high cost and the risk-benefit relationship. This review attempts to provide an overview about this new hospital drug.
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PMID:[Drotrecogin alfa (activated): specific treatment for serious sepsis]. 1577 3

Coagulation activation with intravascular fibrin formation is a general finding in patients with sepsis. Low coagulation factors may be caused by disseminated intravascular coagulation, as well as by loss of plasma and impaired hepatic synthesis in the course of sepsis. The leading clinical symptom in consumption coagulopathy is bleeding. Therefore, treatment mainly consists of substitution of coagulation factors and platelets. Meningococcal and pneumococcal, as well as some other infections may lead to sepsis-induced purpura fulminans, a condition associated with microvascular thrombosis, necrosis, and haemorrhage. A typical laboratory sign is a very low plasma protein C level. Treatment with protein C concentrate or recombinant activated protein C (Drotrecogin alfa, activated) has been shown to be beneficial in sepsis-induced purpura fulminans. Unfractionated heparin or low molecular weight heparin has been recommended for prophylaxis of venous thrombosis, but there are no clinical studies specifically on patients with sepsis. Antithrombin concentrate is used in patients with antithrombin deficiency treated with heparin for acute venous thrombosis or embolism, extracorporeal circulation procedures or other invasive procedures. There is no indication for general use of antithrombin concentrate in patients with sepsis even in patients with low plasma antithrombin levels. Drotrecogin alfa, activated, is used for treatment of patients with severe sepsis. Its use is not limited to patients with sepsis-induced disseminated intravascular coagulation, although these patients appear to benefit especially from this therapy.
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PMID:[Sepsis-associated coagulation disorders]. 1592 56

The protein C pathway serves as a modulating system with both anti-inflammatory and anticoagulant properties and is intimately involved in the pathophysiology of inflammation and sepsis. Treatment with recombinant human activated protein C (rhAPC) can reduce the mortality of severe sepsis. We investigated whether an elevation of plasma protein C levels to supra-normal levels by infusion of a protein C zymogen concentrate has an effect on coagulation, protein C activation or inflammation in a human endotoxemia model. Eleven healthy male volunteers were enrolled in a double-blind, placebo-controlled two-way cross-over trial. Ten minutes after infusion of 2ng/kg endotoxin each volunteer received either placebo or a plasma-derived protein C zymogen concentrate (Ceprotin, Baxter) (150 U/kg as a slow bolus infusion followed by 30 U/kg/h continuous infusion until 4 hours after LPS-infusion). Protein C antigen and activity increased 4- to 5-fold after infusion of the concentrate. APC was generated during endotoxin-induced inflammation in the placebo (1.6 fold increase) and the protein C period (4.0-fold increase). The increase of APC levels correlated with the TNF-alpha and IL-6 release in both periods (r = 0.65-0.68; p < 0.05) and paralleled the protein C antigen and activity levels in the period with supranormal protein C levels. Supra normal protein C levels resulted in slightly, although non-significant, lower tissue factor mRNA expression and thrombin generation (TAT, F1+2). Systemic inflammation (TNF-alpha, IL-6) was not influenced by protein C zymogen concentrate administration. Infusion of protein C zymogen was safe and no adverse effects occurred. The increase of protein C levels several fold above the normal range resulted in a proportional increase of the APC levels, but had no major anticoagulant, anti-inflammatory or profibrinolytic effects. Low grade endotoxemia itself induces significant protein C activation, which correlates with the TNF release.
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PMID:The effects of supra-normal protein C levels on markers of coagulation, fibrinolysis and inflammation in a human model of endotoxemia. 1673 92

The predictive value of plasma protein C level in sepsis has been demonstrated in a number of studies in which depressed protein C levels were associated with increased likelihood of negative outcome. Data from the PROWESS (Recombinant Human Activated Protein C Worldwide Evaluation in Severe Sepsis) trial indicate that administration of drotrecogin alfa (activated; DrotAA) leads to an increase in endogenous protein C levels in severe sepsis patients. In a group as heterogeneous as sepsis patients, the currently approved dose and duration of administration (24 mug/kg per hour for 96 hours) might not be optimal in some individuals. The RESPOND (Research Evaluating Serial Protein C levels in severe sepsis patients ON Drotrecogin alfa [activated]) trial is a phase II study being conducted to explore the use of endogenous protein C level as both a biomarker and a steering parameter for administration of DrotAA. Eligible patients will receive DrotAA either at the normal, currently approved dose and duration of administration ('standard therapy') or at a higher dose with variable infusion duration or variable infusion duration only ('alternative therapy'). The duration of DrotAA infusion in the alternative therapy arm depends on the individual response in terms of sustained increase in endogenous protein C. The ultimate aims of this and potential following studies are as follows: to establish serial plasma protein C measurement as a biomarker that will aid in the identification of severe sepsis patients who are most likely to benefit from DrotAA therapy, to enable adjustment of DrotAA therapy in individual patients (specifically, the possibility to use a higher dose and to adjust the infusion duration), and to provide guidance to the clinician regarding whether the patient is responding to DrotAA.
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PMID:The protein C pathway: implications for the design of the RESPOND study. 1826 91

A 13-month-old Japanese female with Haemophilus influenzae type b meningitis presented with unusually severe septic shock and cerebral infarction in half a day of fever. The initial therapy of plasma-derived activated protein C (Anact C) led to an impressive effect on the aggressive condition. However, purpura fulminans and the consistent decline of plasma protein C activity (<20%) required prolonged activated protein C therapy and gene analysis. The patient carried a novel heterozygous mutation of PROC (exon 4; 335 GAC>TAC, Asp46Tyr). This is the first report of infectious purpura fulminans in a protein C-deficient heterozygote. The clinical onset and treatment course adequately corroborated the aggravated immune/hemostatic reactions and the cytoprotective effects of activated protein C replacement in human heterozygous protein C deficiency. The monitoring of plasma protein C activity and sufficient administration of activated protein C product could improve the outcome of severe sepsis in children.
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PMID:Fulminant sepsis/meningitis due to Haemophilus influenzae in a protein C-deficient heterozygote treated with activated protein C therapy. 1875 23


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