Search results for "Factor XII"

Spontaneous chronic subdural hematomas in young adults with a deficiency in coagulation factor XIII. Report of three cases

2005

✓ Chronic subdural hematomas (SDHs) generally occur in elderly patients. Its pathogenesis is usually related to head trauma with tearing and rupture of the bridging veins, although in some cases a history of trauma is not recognizable. There are many reports regarding the association between spontaneous chronic SDHs and an alteration in coagulative parameters. A coagulative disorder should be suspected when an unexplained hemorrhage occurs, especially in a young patient. The authors report on three young men with a deficiency in coagulation factor XIII (FXIII) who underwent surgery for chronic SDHs. The role of FXIII in the pathogenesis of chronic SDH is emphasized. In patients with unexpla…

Antibody-mediated inhibition of FXIIa blocks downstream bradykinin generation.

2018

Analysis of cold activation of the contact system in hereditary angioedema with normal C1 inhibitor.

2021

Hereditary angioedema (HAE) attacks are caused by excessive activation of the contact system. Understanding how the contact system is activated in HAE, especially in patients with normal C1 inhibitor (HAEnCI), is essential to effectively treat this disease. Contact system activation involves the cleavage of several proteins including Factor XII (FXII), high molecular weight kininogen (HK), prekallikrein, sgp120 (ITIH4) and C1 inhibitor (C1-INH) before the subsequent generation of bradykinin that mediates HAE. In this study, we evaluated the fragmentation and enzymatic activity of contact system proteins in HAEnCI plasma samples before and after contact system activation induced by incubatio…

Mutations in the Factor XII Gene in Solitary Cases of Recurrent Angioedema with Normal C1 Inhibitor Induced or Worsened by Oral Contraceptives or Hor…

2012

An Evaluation of Fibrin(ogen) Determinants of Thromboelastography

2011

Abstract Abstract 2251 Thromboelastography (TEG) was used in ∼200 studies published in 2009, is mainly used for global blood coagulation assessment, and is thrombin and fibrinogen concentration-dependent. Reflecting the time course of fibrin polymerization, TEG measures lag time, rate, and maximum amplitude (MA) of clot stiffness, and is substantially enhanced by platelets. To identify more specific fibrin(ogen) determinants potentially relevant to interpretation we investigated MA under different TEG conditions. The procedure utilizes a polymethylmethacrylate (hydrophobic surface) cup and pin set, the cup oscillating through 4° 45' (6 cycles/minute). The pin (sensor) is suspended via a tor…

Characterization of a partial exon 9/intron 9 deletion in the coagulation factor XII gene (F12) detected in two Turkish families with hereditary angi…

2014

Blood coagulation factor XII drives adaptive immunity during neuroinflammation via CD87-mediated modulation of dendritic cells

2016

Aberrant immune responses represent the underlying cause of central nervous system (CNS) autoimmunity, including multiple sclerosis (MS). Recent evidence implicated the crosstalk between coagulation and immunity in CNS autoimmunity. Here we identify coagulation factor XII (FXII), the initiator of the intrinsic coagulation cascade and the kallikrein–kinin system, as a specific immune cell modulator. High levels of FXII activity are present in the plasma of MS patients during relapse. Deficiency or pharmacologic blockade of FXII renders mice less susceptible to experimental autoimmune encephalomyelitis (a model of MS) and is accompanied by reduced numbers of interleukin-17A-producing T cells.…

Increased Activity of Coagulation Factor XII (Hageman Factor) Causes Hereditary Angioedema Type III

2006

International audience; Hereditary angioedema (HAE) is characterized clinically by recurrent acute skin swelling, abdominal pain, and potentially life-threatening laryngeal edema. Three forms of HAE have been described. The classic forms, HAE types I and II, occur as a consequence of mutations in the C1-inhibitor gene. In contrast to HAE types I and II, HAE type III has been observed exclusively in women, where it appears to be correlated with conditions of high estrogen levels--for example, pregnancy or the use of oral contraceptives. A recent report proposed two missense mutations (c.1032C-->A and c.1032C-->G) in F12, the gene encoding human coagulation factor XII (FXII, or Hageman factor…

Measurement of Bradykinin Formation and Degradation in Blood Plasma: Relevance for Acquired Angioedema Associated With Angiotensin Converting Enzyme …

2020

Bradykinin (BK)-mediated angioedema (AE) states are rare acquired or hereditary conditions involving localized edema of the subcutaneous and submucosal tissues. Citrated plasma from healthy volunteers or patients with hereditary angioedema (HAE) with normal level of C1-inhibitor (C1-INH) was used to investigate pathways of BK formation and breakdown relevant to AE physiopathology. The half-life of BK (100 nM) added to normal plasma was 34 s, a value that was increased ~12-fold when the angiotensin converting enzyme (ACE) inhibitor enalaprilat (130 nM) was added (enzyme immunoassay measurements). The BK half-life was similarly increased ~5-fold following 2 daily oral doses of enalapril malea…

Hereditary angioedema caused by missense mutations in the factor XII gene: clinical features, trigger factors, and therapy.

2009

Background Hereditary angioedema caused by mutations in the factor XII gene is a recently described disease entity that occurs mainly in women. It differs from hereditary angioedema caused by C1 inhibitor deficiency. Objective To assess the clinical symptoms, factors triggering acute attacks, and treatments of this disease. Methods Thirty-five female patients with hereditary angioedema and the factor XII mutations p.Thr309Lys and p.Thr309Arg who came from 13 unrelated families were studied. The observation period was 8.4 years on average (range, 2-26 years). Results Patients had on average 12.7 ± 7.9 angioedema attacks per year. Recurrent facial swellings occurred in all patients; skin swel…