1/27. Bleeding disorder with abnormal wound healing, acid-soluble clots and normal factor XIII.An unusual bleeding disorder clinically resembling factor xiii deficiency is presented. The only detectable coagulation abnormality was rapid clot dissolution in 1% monochloroacetic acid. This abnormality was ascribed to the sustained increase of a pepsin-like plasma protease which is activated at low pH. Asystematic search for similar phenomena revealed that massive blood transfusion may also enhance plasma-clot solubility in acid, possibly by release of a red cell protease. We conclude that the acid clot solubility test is not a specific indicator of factor xiii deficiency, but this simple assay is recommended for further studies of acid plasma protease activity. The diagnostic relevance and pathophysiologic importance of increased pepsin-like activity in plasma remain to be elucidated.- - - - - - - - - - ranking = 1keywords = coagulation (Clic here for more details about this article) |
2/27. Maternal blood coagulation factor XIII is associated with the development of cytotrophoblastic shell.We analysed the early implantation tissues of normal women and of a patient with congenital factor xiii deficiency in order to study the role of maternal subunit A of factor XIII (XIIIA) in the development of extravillous cytotrophoblast. The patient had received adequate administration of factor xiiia concentrate only up to 7 weeks of gestation (wG). Her pregnancy was maintained until the latter half of 8 wG, but was terminated by intrauterine fetal death at 9 wG. Immunohistochemical staining of cytokeratin, XIIIA and subunit S of factor XIII was performed in the early implantation tissues of normal women and of this patient. Numerous well-formed cytotrophoblastic shells and Nitabuch's layers were detected in implantation tissues at 7-8 wG in normal women, and XIIIA was present in the intercellular space in well-formed cytotrophoblastic shells, while the cytotrophoblastic shells and Nitabuch's layers in this patient's implantation tissue were poorly-formed. Furthermore, XIIIA was not detected around them. It is suggested that when the maternal plasma activity of factor XIII is low, the concentration of XIIIA at the placental bed is also low, leading to the insufficient formation of cytotrophoblastic shell and therefore an increased probability of miscarriage in patients with congenital factor xiii deficiency.- - - - - - - - - - ranking = 4keywords = coagulation (Clic here for more details about this article) |
3/27. Identification of a new mutation (Gly420Ser), distal to the active site, that leads to factor xiii deficiency.The molecular defects of the factor XIII A subunit gene were studied in a patient with factor xiii deficiency. Mutation analysis was performed on amplified dna from each exon of this gene by single-strand conformation polymorphism (SSCP) and dna sequencing techniques. A substitution of guanine by adenine at nucleotide 1258 in exon 10 of the coagulation factor XIII A subunit gene has been identified in the patient. The mutation results in the replacement of Gly420 by Ser in the core domain of the enzyme. Restriction enzyme analysis of amplified exon 10 dna confirmed that the patient was homozygous for this mutation. A family study revealed that the mutation was inherited from both parents, who were first cousins. The potential effects of the mutation were predicted by molecular modeling of the amino acid substitution within the coordinates of the crystal structure. The substitution occurred within the core domain of the enzyme at a residue completely conserved among all known members of the transglutaminase family. The model of the mutant protein suggests that although the substitution of Gly420 by Ser causes only minor readjustment of the residues and does not appear to be particularly deleterious in terms of structure, the mutation is, however, likely to decrease the molecule's ability to undergo the conformational change that is thought to be required for full transglutaminase activity. Our data strongly support the previously published information about the functional significance of the residues surrounding, but not forming, the catalytic pocket in the A subunit of factor XIII.- - - - - - - - - - ranking = 1keywords = coagulation (Clic here for more details about this article) |
4/27. Novel Y283C mutation of the A subunit for coagulation factor XIII: molecular modelling predicts its impaired protein folding and dimer formation.In an Italian patient with severe factor xiii deficiency, a novel mutation, Y283C (TAT to TGT), was identified heterozygously by nucleotide sequencing analysis in exon VII of the gene for the A subunit. The presence of this mutation was confirmed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in the proband and his brother. Molecular modelling predicts that the mutant molecule would be misfolded. It is probable that the impaired folding of the mutant Y283C A subunit led to its instability, which is at least in part responsible for the factor xiii deficiency of this patient.- - - - - - - - - - ranking = 4keywords = coagulation (Clic here for more details about this article) |
5/27. Mutations in coagulation factor XIII A gene in three Turkish patients: two novel mutations and a known insertion.Molecular analysis of factor XIII A gene on three unrelated Turkish families identified two novel and one known mutations. One novel mutation is a substitution of cytidine by guanine at codon 541 in exon 12, beta barrel 1 domain of the coagulation factor XIII A subunit gene resulting in the conversion of asparagine to lysine. The mutation alters the restriction site of the enzyme MboII. The second novel mutation, a 4 bp (-CAAA) deletion located in a direct repetitive sequence (CAAACAAA) between codons 466-469, results in premature termination of translation at codon 474. The third mutation is a previously reported single nucleotide (cytidine) insertion at codon 400 in exon 9 of the factor XIII gene.- - - - - - - - - - ranking = 5keywords = coagulation (Clic here for more details about this article) |
6/27. Identification of a point mutation in factor XIII A subunit deficiency.Oligonucleotide primers have been designed for the amplification of all 15 exons of the human coagulation factor XIII A subunit gene. Each exon and its intron flanking regions has been amplified and sequenced from a patient with severe A subunit deficiency. A single G to A transition in the last base of exon 14 has been identified in the homozygous proband and in his heterozygous parents. The mutation would result in the substitution 681 Arg to His in the mature protein product. However, because the mutation is at a splice junction, the deficiency may result from a defect in pre-messenger rna splicing.- - - - - - - - - - ranking = 1keywords = coagulation (Clic here for more details about this article) |
7/27. Congenital factor xiii deficiency.Clinical and hematological data of 9 cases with factor xiii deficiency is highlighted. The age at first bleed ranged from 3 days of life to 1 year. Seven of these 9 cases had bleeding from the umbilicus, 3 had recurrent subcutaneous and muscle hematomas, while 4 cases had CNS bleeds of which 3 expired. Routine coagulogram was normal, while clot solubility in 5 molar urea solution was abnormal in all cases. Factor XIII assay was not done in any. patients were treated with plasma transfusion during episodes of bleeding. No patient received plasma transfusion as prophylactic therapy. The cumulative Indian data so far documented, inclusive of this series, shows a very high incidence of CNS bleeds (33%) in patients with this inherited coagulation disorder.- - - - - - - - - - ranking = 1keywords = coagulation (Clic here for more details about this article) |
8/27. factor xiii deficiency associated with valproate treatment.PURPOSE: We present two children who developed a deficiency of factor XIII with valproate (VPA) treatment. This coagulation disorder has not been described in association with VPA treatment in children, and only very recently in one adult patient. RESULTS: Both patients showed recurrent epistaxis as major clinical sign of a combination of decreased coagulation parameters (factor xiii deficiency with thrombocytopenia and decreased von willebrand factor, respectively). A few days after reduction or withdrawal of VPA treatment, clinical symptoms disappeared, and laboratory findings were within normal range. CONCLUSIONS: VPA is known to influence the synthetic function of the liver and the number and function of megakaryocytes. Therefore an alteration of the factor XIII level by VPA is conceivable. Our case reports suggest that bleeding symptoms during VPA treatment may be caused or aggravated by a decreased factor XIII activity. A determination of factor XIII activity should be considered before surgical procedures during VPA treatment to minimize the risk of (severe) postsurgical bleeding complications.- - - - - - - - - - ranking = 2keywords = coagulation (Clic here for more details about this article) |
9/27. Spontaneous chronic subdural hematomas in young adults with a deficiency in coagulation factor XIII. Report of three cases.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 unexplained chronic SDH all coagulation parameters and factors should be screened to identify an eventual coagulative disorder.- - - - - - - - - - ranking = 6keywords = coagulation (Clic here for more details about this article) |
10/27. Deficiency of coagulation factor XIII A subunit caused by the dinucleotide deletion at the 5' end of exon III.A congenital deficiency of the coagulation Factor XIII A subunit (F XIII A) is a rare autosomal recessive disorder that is characterized by a life-long bleeding tendency complicated by a difficulty in healing. Thus far, no molecular genetic analysis of this disorder has been reported. In this study, we demonstrate the molecular abnormalities in a family with this disorder. We performed Northern blot analysis of peripheral blood monocytes obtained from the propositus and found a 4-kb single band of F XIII A mRNA whose size was identical with that of normal subjects. exons II-XV, which encode all the amino acids, were individually amplified by a polymerase chain reaction (PCR). All PCR products from the propositus had lengths indistinguishable from those of the wild type on agarose gel, suggesting that this defect results from either a point mutation or a short deletion/insertion. The sequencing of F XIII A cDNA from the propositus revealed a deletion of the dinucleotide AG within the AGAG repeat at the position of 210 to 213. Concerning the genomic sequence, a deletion of dinucleotide AG was also demonstrated in the intron B-exon III boundary. This deletion appeared to cause a frameshift mutation making a new stop codon shortly thereafter, and leading to a deficiency of plasma F XIII A. The heterozygosity of the F XIII A deficiency in the patient's offspring was documented by the nucleotide sequences of their exon III.- - - - - - - - - - ranking = 5keywords = coagulation (Clic here for more details about this article) |
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