Summary Three related patients are presented who show a congenital coagulation disorder with laboratory features intermediate between classical factor‐VII and factor‐X deficiencies. A woman and two men had suffered from bleeding since early childhood, with epistaxis, bleeding from the gums, post‐traumatic haemarthroses, bleeding after tooth extractions and other surgical procedures. Investigation demonstrated a prolonged prothrombin time, prolonged partial thromboplastin time, abnormal prothrombin consumption and abnormal thromboplastin generation corrected by normal serum. Platelet and vascular tests were normal and no hyperfibrinolysis was found. Factors I, II, V, VII, IX, XI and XII were within normal limits in all three patients. Mutual correction was demonstrated with a known factor‐VII‐deficient plasma but not with Stuart (X‐deficient) plasma. Factor‐X assay yielded low (4–9%) levels using tissue whole thromboplastin or tissue partial thromboplastin; but the results were normal with a Stypven‐cephalin mixture. In agreement with these results, the Stypven‐cephalin clotting time, the Stypven clotting time and the factor II + factor X level using a Stypven‐cephalin mixture were normal, ‘correction’ being attributable to the Russell's Viper venom. These results were thought to indicate an abnormal factor X rather than a real deficiency. The presence of abnormal factor X was demonstrated by the antibody neutralization technique and by the immunodiffusion studies. The defect, like classical factor X deficiency, is transmitted as an autosomal incompletely recessive trait. The heterozygote population has factor‐X levels varying from 32% to 55% of normal and are usually asymptomatic. The term ‘Factor X Friuli’ is proposed for the abnormality, due to a locally common mutant gene.
SummaryA case of severe congenital factor X deficiency is presented. The patient was a 5 month old child who had several episodes of melena since the first weeks of life. Other bleeding manifestations were subcutaneous hematomas and a massive brain hemorrhage. The prothrombin time was severely prolonged and was corrected by normal serum, aged normal plasma and by the plasma of patients with parahemophilia, congenital hypoprothrombinemia and factor VII deficiency. On the contrary adsorbed normal plasma and Mr. Stuart’s plasma failed to correct the abnormality.The partial thromboplastin time, prothrombin consumption and the thromboplastin generation test were abnormal too. The T.G.T. was corrected by the substitution of the patient’s serum with normal serum. The factor X level was less then 0.1% of normal. All other clotting factors were within normal limits.Both parents of the “propositus” showed slightly decreased levels of factor X in their plasmas and were considered to be heterozygotes for the defect.
Summary It is not yet clear whether some polymorphic variants of the Ha-ras-1 gene confer genetic predisposition to cancer. However, recent data on myelodysplasia and lung cancer are controversial. To clarify this point, 62 colorectal adenocarcinoma patients were examined for the Ha-ras-I gene restriction fragment length polymorphism and results were compared with those of 108 healthy blood donors. No Haras-1 polymorphic variants specifically associated with the cancer patients were detected. However, a specific genotype was significantly more frequent in the healthy donors than in the cancer patients (16% versus 5%), suggesting an interaction between the two alleles of the gene.Tumours of different histological types, both in human and blood donors (HBD) by restriction fragment length polyin animal systems, have been found to be associated with ras morphism (RFLP). proto oncogenes activated by mutation and/or overexpression. Activation by mutation has been demonstrated by the DNA Materials and methods transfection technique and ascribed to somatic single base mutations in the region of the 12th and/or 61st codons
A 23‐year‐old white male with a bleeding tendency since early childhood presented a congenital coagulation defect similar but not identical to factor X deficiency. A first and second stage defect were demonstrated, characterized by a prolonged prothrombin time, prolonged partial thromboplastin time, abnormal thromboplastin generation, abnormal prothrombin consumption. The Stypven clotting time was slightly prolonged on fresh plasma but was normal on frozen plasma. Factors I, II, V, VIII, IX, XI, and XII were all within normal limits; factor VII was at the lower limits of normally or slightly decreased. Mr. Stuart's plasma failed to correct the defect of the patients plasma; however, a known factor VII deficient plasma was able to correct the abnormality. Factor X levels showed low (3–13%) only when assayed using tissue whole thromboplastin or tissue partial thromboplastin; the factor X assay using a Stypven‐cephalin mixture yielded normal or near normal values. The factor II + factor X level using a Stypven‐cephalin mixture appeared normal also. The significance of the findings is discussed. The results are tentatively interpreted as being due to an abnormal factor X rather than to a real deficiency.
Hb Contaldo with a His----Arg substitution at position 103(G10) of the alpha chain is a newly discovered unstable Hb variant observed in an Italian child. Its instability is probably due to the disruption of the hydrogen bond between alpha 103(G10)His and beta 108(G10)Asn. The structural variation in the core segment was determined through analysis of tryptic peptides from digests of the alpha X and oxidized alpha X (with performic acid) chains, which were separated by HPLC. Similar analyses were made for the alpha X chain of the rare Hb Manitoba in which alpha 102(G9) Ser is replaced by Arg. This variant was observed for the first time in an Italian patient, and was also studied in a member of a previously described Canadian family.
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