Search results for "Complement C1"
showing 10 items of 125 documents
C1-esterase inhibitor reduces infarct volume after cortical vein occlusion.
1999
In order to clarify the role of complement as a mediator of cerebral infarct growth, we inhibited the classical complement activation pathway in a photochemical cortical vein occlusion model. Immediately after occlusion, rats were infused with either 0.9% saline (vehicle), or C1-esterase inhibitor (C1-INH) over 30 min. Regional cerebral blood flow (rCBF) decreased after occlusion, and was about 50% of baseline after 2 h. No difference was noted between experimental groups. Mean arterial blood pressure (MABP) and arterial blood gases were likewise unaffected by the treatment. However, administration of C1-INH had significantly reduced infarct volume by 72%, as evaluated after 5 days survival…
Proteome analysis of myocardial tissue following ischemia and reperfusion--effects of complement inhibition.
2006
Myocardial ischemia-reperfusion injury can be related to complement activation with generation of chemotactic mediators, release of cytokines, leukocyte accumulation, and subsequent severe tissue injury. In this regard, activation of transcription factors (i.e., NFkappaB) and de novo protein synthesis or inflammatory protein degradation seems to play an important role. In the present study, we analyzed the cardiac protein expression following myocardial ischemia (60 min) and reperfusion (180 min) in a rabbit model utilizing two-dimensional electrophoresis and nanoHPLC/ESI-MS/MS for biochemical protein identification. To achieve cardioprotective effects, we used a novel highly selective smal…
Beneficial effects of C1 esterase inhibitor in ST-elevation myocardial infarction in patients who underwentsurgical reperfusion: a randomized double-…
2007
Background: The inflammatory cascade has been hypothesized to be an important mechanism of post-ischaemic myocardial reperfusion injury and several studies demonstrated that C1 esterase inhibitor (C1 -INH) is effective in post-ischaemia myocardial protection. Therefore, we aimed to investigate prospectively in a randomised double-blind study the cardioprotective effects of C1-INH in ST segment elevation myocardial infarction (STEMI) in patients who underwent emergent reperfusion with coronary artery bypass grafting (CABG). Methods: In this study, we enrolled 80 patients affected with STEMI who underwent emergent CABG. Patients were assigned in two groups (C1-INH group: receive 1000 Ul of C1…
Molecular Basis of Hereditary C1q Deficiency
1998
Abstract Complete selective deficiencies of the complement component C1q are rare genetic disorders which are associated with recurrent infections and a high prevalence of lupus erythematosus-like symptoms. The improvements in molecular biology techniques have facilitated the analysis of such genetic defects to a great extend. To date the basis of C1q deficiencies from 13 families have been studied at the genetic level. In each case single base mutations leading to either termination codons, frame shift or amino acid exchanges were thought to be responsible for these defects as no other aberrations were found. In addition to DNA analysis, conventional immunochemical and biochemical methods …
Disulfide bridge formation between C1q and IgG in vitro.
1990
The globular heads of C1q are known to possess free-SH groups. Here we show that these groups, which are concealed in the native molecule, are exposed by interaction of C1q with dialysis membrane. During iodination, I+ and I2 oxidize these sulfhydryls to produce disulfide-linked C1q aggregates. Approximately 15% of C1q bound to immunoglobulin aggregates is resistant to high conductivity elution and reducing agent is required to release it. These data show that dialysis, adsorption to Ig and iodination of C1q result in structural and functional changes in the molecule, and suggest a mechanism by which these changes occur. Disulfide bridging between C1q and IgG in vitro suggests that this may…
C1-Esterase-Inhibitor Treatment at Early Reperfusion of Hemorrhagic Shock Reduces Mesentery Leukocyte Adhesion and Rolling
2001
Objective: Complement activation probably plays a pathogenic role in multiple organ failure in shock. This study evaluates the effects of C1-esterase-inhibitor treatment on leukocyte-endothelial interaction in the mesenteric microcirculation in hemorrhagic shock. Methods: Rats underwent median laparotomy and exteriorization of an ileal loop for intravital microscopy of the mesenteric microcirculation. Volume controlled hemorrhagic shock was provoked by arterial blood withdrawal (2.5 mL/ 100 g body wt. for 60 minutes) followed by a 4-hour reperfusion period. C1-INH (100 IU/kg body wt. i.v.) or 0.9% NaCl i.v. were administered as a bolus at the beginning of reperfusion. Reperfusion time mimic…
Evidence that C1q, a Subcomponent of the First Component of Complement, is an Fc Receptor of Peritoneal and Alveolar Macrophages
1980
Abstract Guinea pig peritoneal macrophages were cultured for 24 h in the presence of two inhibitors of the biosynthesis of collagen-like molecules such as C1q : 10 -3 M 3,4-dehydroproline or 10 -4 M 2,2′-dipyridyl. Their Fc-receptor activity was measured by rosette formation, using sheep erythrocytes (E) coated with rabbit anti-sheep IgG (EA IgG ). The Fc-receptor activity was decreased by 40 to 70% of control cultures depending on the amount of IgG on the E. The activity of a second receptor on the macrophages, mediating the binding of C3b coated E, was not altered by this treatment. Rat alveolar macrophages were depleted of their Fc-receptor activity by pronase treatment (1.5 mg/ml) in th…
Molecular, Genetic and Epidemiologic Studies on Selective Complete C1q Deficiency in Turkey
2000
Selective complete C1q deficiencies (SCDC1q) of the complement component C1q are rare genetic disorders with high prevalence of lupus-erythematosus-like symptoms and recurrent infections. Among the 41 published cases from 23 families, 10 derive from 6 Turkish families. One particular mutation leading to a stop codon in the C1q A gene was first identified in members of a Gypsy family from the Slovac Republic. Later the same mutation has been found in all cases in four SCDC1q families from Turkey suggesting that one particular defective allele may be present in the populations of Southeastern Europe and Turkey. This study was undertaken to investigate the frequency of C-->T mutation in exon I…
Complement Activation in Peritoneal Dialysis–Induced Arteriolopathy
2017
Cardiovascular disease (CVD) is the leading cause of increased mortality in patients with CKD and is further aggravated by peritoneal dialysis (PD). Children are devoid of preexisting CVD and provide unique insight into specific uremia- and PD-induced pathomechanisms of CVD. We obtained peritoneal specimens from children with stage 5 CKD at time of PD catheter insertion (CKD5 group), children with established PD (PD group), and age-matched nonuremic controls (n=6/group). We microdissected omental arterioles from tissue layers not directly exposed to PD fluid and used adjacent sections of four arterioles per patient for transcriptomic and proteomic analyses. Findings were validated in omenta…
Coagulation factors and proteinase inhibitors in the plasma of children with acute lymphoblastic leukoses. Behaviour before and during treatment acco…
1984
The thrombocyte count, the factor XIII (F XIII) activity, the concentration of fibrinogen (F I), prothrombin (F II), fibronectin (CIG), albumin and the proteinase inhibitors antithrombin III (AT III), alpha 2-macroglobulin (A2M), alpha 1-antitrypsin (A1A) and Cl-esterase inactivator (Cl-INA) were determined in ten children with acute lymphoblastic leukaemia (ALL). Changes due to the disease and to therapy were observed. Before the start of treatment the patients had thrombocytopenia secondary to the disease, and the proteinase inhibitors--especially Cl-INA and A1A--were raised. During the induction phase the thrombocyte count rose but there was also a marked increase in the concentration of…