SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
A "new" antithrombin III abnormality is described in four members of a family. The proposita is a 38 years old female who showed no thrombotic disease and the following laboratory pattern: normal routine clotting tests, normal or near normal AT III activity (chromogenic substrates S-2238 and Chromozym Th) both in plasma and in serum and in the presence or absence of heparin, slightly decreased antifactor Xa activity (chromogenic substrate S-2222), normal progressive antithrombin, normal AT III antigen but abnormal migration in the agarose-heparin bidimensional system. In the latter test, one major abnormal peak, less anodal than the normal counterpart, and a smaller, apparently normal peak, were seen. In agarose without heparin the pattern was similar to normal both in plasma and in serum. Heparin tolerance to heparin in vivo and in vitro was slightly increased but still within normal limits. The two sons and a paternal aunt showed the same pattern. The hereditary pattern seems therefore autosomal dominant. The abnormality described appears different from AT III Budapest. The toponym of antithrombin III Padua is proposed to define this peculiar abnormality.
Explore the source record for details and available documents.
Rats infected with Trypanosoma brucei rhodesiense developed anemia, thrombocytopenia, and hypocomplementemia. Anemia, thrombocytopenia, and sharp reductions in parasitemia were associated with elevated titers of cold-active hemagglutinin, antibody to fibrinogen/fibrin-related products, and immunoconglutinin. Depletion of lytic complement, prolonged partial thromboplastin times, and presence of fibrin monomers in the blood occurred at the time anemia and significant elevations in precipitable immune complexes were observed. Terminally, consumption of immunologic factors coincided with accelerated partial thromboplastin times. At death, convulsions and hemoptysis with labored breathing suggested that the animals died of respiratory failure and that disseminated intravascular coagulation may have occurred. It is suggested that microthrombiosis might have resulted from the immunologic interaction of complex-coated blood cells with immunoconglutinin and contributed to the terminal disease signs.
Explore the source record for details and available documents.
In this work we analyse the information about one group of young patients with cerebrovascular disease, studying the association between haematological pathology and cerebrovascular disease. The objective is to establish a comparison between our results and those previously reported in the medical literature.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
In studies conducted about 8 years ago, the author and her colleagues raised a monoclonal antibody that recognized an uncharacterized human platelet protein with a reduced molecular mass of 155 kDa. Investigations of this protein's nonreduced structure yielded surprising findings: in its native state, it exists as massive disulfide-linked multimers millions of daltons in size, making it one of the largest proteins found in the human body. This feature led the author to designate this protein "multimerin." Multimerin is found in endothelial cells as well as in platelets. It originates from a single subunit protein, promultimerin, that undergoes extensive N-glycosylation, proteolytic processing and polymerization during biosynthesis. Recent data from the cloning and sequencing of its complementary DNA indicate that multimerin is a unique protein. Like von Willebrand factor, it has a massive repeating structure, but these proteins are unrelated. Multimerin's sequence contains the adhesive motif Arg-Gly-Asp-Ser, central coiled-coil sequences, several epidermal growth-factor-like motifs, and a globular domain that is similar to a protein-binding domain found in complement C1q and in collagens type VIII and X. Investigations of multimerin's function indicate that it binds the coagulation protein factor V and its activated form, factor Va. In platelets, but not in plasma, all of the biologically active factor V is complexed with multimerin. Multimerin may also have functions as an extracellular matrix or adhesive protein. Recently, members of 2 Canadian families with puzzling autosomal-dominant bleeding disorders were found to have a deficiency of platelet multimerin. Studies of these patients may provide a unique opportunity to evaluate the functions of multimerin.
Less common than acquired bleeding disorders in the perinatal period, congenital deficiencies of the clotting proteins, particularly the hemophilias A and B, can be just as devastating. Detection of these disorders may be delayed because a suspect family history is lacking in up to one third of the cases of hemophilia, and parents are usually asymptomatic in the other congenital factor deficiencies. Physiologically low levels of the liver-dependent and contact factors can make the interpretation of the common hemostasis screens difficult. Hence, the use of age-adjusted tables such as those presented here is essential. Congenital deficiencies of clotting proteins should be suspected when serious CNS bleeding occurs in an otherwise healthy baby generally after a day or two. Factor XIII or other less common factor deficiencies should be sought when there is prolonged bleeding from the umbilical stump. Bleeding after circumcision is a rare early indicator nowadays with better techniques. The availability of bedside ultrasound to detect CNS hemorrhage early and of fresh frozen plasma for treatment preceding the results of specific factor assays should prevent serious sequelae. Elective cesarean section is currently recommended when an unborn infant is known to have hemophilia.
Resistance to activated protein C is a newly described genetic coagulation disorder previously only reported in patients with venous thromboembolism or central arterial embolism (cerebral or coronary). We report this defect in association with digital artery thrombosis and describe the pathophysiology of this disorder.
The aim of the present study was to determine plasma levels of protein C antigen (PC:Ag) and activity (PC:Act), tissue factor pathway inhibitor (TFPI), protein S (PS), antithrombin (AT), heparin cofactor II (HCII), and resistance to activated protein C (APCR) before, during and after elective gastric surgery in order to compare patients with and without gastric malignancy. Blood was collected from a forearm vein of two age-matched patient groups undergoing elective gastric surgery, 9 patients with and 9 patients without gastric malignancy. The plasma levels of the parameters were determined preoperatively, intraoperatively, and on days 1 and 7 postoperatively. On the 1st and 7th postoperative day, plasma levels of HCII were significantly lower in patients operated for gastric malignancy than in those operated for benign disorders, but levels of TFPI, PC:Act, PC:Ag, AT, PS and APCR did not differ in the postoperative period. The day-to-day variation was also rather similar in the two patient groups.
Congenital and acquired hemostatic disorders present during childhood. An accurate diagnosis is critically important in order to implement optimal therapy. Over the last century, several investigators have measured plasma concentrations of hemostatic components in newborns and compared the results to adult values. Clinically significant differences exist for many hemostatic components. Recently, three large studies in more than 400 healthy children have provided reference ranges for hemostatic components throughout childhood. Together, these studies provide insight into the regulation of coagulation and fibrinolysis in children in physiologic and pathologic states. Some examples of the influence of age on hemostasis are: (1) the diagnosis of some congenital factor deficiencies, based on plasma levels, can be difficult due to physiologically low values; (2) despite very low levels of many inhibitors of hemostasis, thrombotic complications are rare; (3) the interaction of anti-coagulants and thrombolytic agents is profoundly influenced by the relative immaturity of hemostasis at birth; and (4) in contrast to the risk of thrombosis, healthy infants are at risk for vitamin K deficiency bleeding due to poor transport of vitamin K across the placenta and plasma concentrations of the vitamin K dependent proteins of less than 50% of adults values. The following review discusses the age dependency of hemostasis during childhood and the effect of the physiologically immature system on the diagnosis and treatment of hemostatic disorders.
Explore the source record for details and available documents.