Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0272170 (SDS)
 50,377 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A bleeding diathesis is described which is phenotypically indistinguishable from hemophilia A and which has been transmitted as a dominant trait in three generations of women in a North Carolina kindred. The abnormal phenotype is characterized by clinical mildness and slightly abnormal clotting time, prothrombin consumption, and partial thromboplastin time. Bleeding time, platelet count, clot retraction, tourniquet test, and prothrombin time are normal. Concentration of factors I, II, V, VII, IX, X, and XII are normal, while factor VIII activity is reduced to 2%-5% of control values. De novo synthesis of factor VIII does not occur after transfusion; factor VIII-related antigen is normal; patients' plasmas aggregate platelets normally in the presence of ristocetin, and a typical protein pattern is seen when a chymotryptic digest of cryoprecipitate of the proband is examined by SDS-polyacrylamide gel electrophoresis. Six possible genetic explanations are entertained. Balanced X-autosomal translocation of hemophilia A heterozygotes has been excluded by cytogenetic analysis of metaphase chromosomes. Classes von Willebrand's disease (vWd) is probably excluded on the basis of the laboratory data, and extreme lyonization of hemophilia A heterozygotes on probabilistic grounds. The genetic possibilities which cannot be excluded include a previously unrecognized variant mutation at the vWd locus, a dominant mutation at the hemophilia A locus on the X chromosome, and dominant mutation at a hypothetical fourth locus involved in factor VIII synthesis and control.
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PMID:Dominant inheritance of hemophilia A in three generations of women. 116 93

The von Willebrand disease (vWD) is the most severe coagulopathy. Because of the complex biochemical structure of the von Willebrand factor (vWF), a great number of types and subtypes of the vWD were found. A screening of vWD can only be done by examining the bleeding time, the ristocetin cofactor activity (risto) and by an immunological determination of the vWF concentration. Examinations of 200 patients with a bleeding tendency showed that the ratio vWF/risto < 0.7 indicates a high probability for an abnormal multimeric structure of vWF. The exact determination of the vWD subtype then has to be done by a SDS-agarose gel electrophoresis. In 16.8% of our patients we found a decreased vWF concentration in the platelets. These patients showed normal plasmatic coagulation factors, but a bleeding tendency and a prolonged bleeding time. For diagnosis of vWD the bleeding time, immunological determination of the vWF and the risto should be done first. If a ratio vWF/risto < 0.7 or a prolonged bleeding time with a bleeding tendency is found, the separation of the vWF multimers into plasma and platelets and the determination of the vWF concentration in platelets should be carried out for an exact diagnosis of vWD.
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PMID:[Diagnostic strategies for detection of the von Willebrand syndrome]. 128 14

A case of acquired von Willebrand's disease (AvWD) associated with an adrenal cortical carcinoma is reported. The circulating highest molecular weight multimers (HMWM) of von Willebrand factor (vWF) were decreased when assessed by SDS-agarose plasma electrophoresis, leading to the diagnosis of type II AvWD. No forms of inhibitor could be detected in the plasma of the patient. In contrast, indirect immunoperoxidase studies with a monoclonal antibody to vWF demonstrated an absorption of vWF into malignant cells. Infusion of a vWF-FVIII concentrate, containing significant amounts of HMWM of vWF, allowed surgical resection of the tumour. After the first infusion of the concentrate, the vWF-RCo recovery was found to be low (38%) compared to the vWF:Ag (75%) and FVIII:C (163%) recoveries. The resolution of all biological signs of vWD, including the abnormal multimeric pattern, in the post-operative period was prompt and permanent. Therefore, the absorption of the HMWM of vWF by carcinomatous cells appears to represent a likely pathophysiological mechanism responsible for the AvWD syndrome in this patient.
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PMID:Acquired type II von Willebrand's disease associated with adrenal cortical carcinoma. 158 Dec 33

We have identified a patient with von Willebrand's disease (vWD) resembling type IIB vWD, with increased ristocetin induced platelet aggregation (RIPA), the absence of the large multimers of von Willebrand factor (vWF) in plasma, and the presence of the large multimers in platelets in whom a family study indicated a probable double heterozygous inheritance pattern. The propositus was a 12-year-old boy with frequent epistaxis and bruising. Abnormal hemostatic findings included a prolonged bleeding time (BT), decreased levels of factor VIII coagulant activity (VIIIC), von Willebrand factor antigen (vWF:Ag), ristocetin cofactor (RCof), and an increased RIPA. In the presence of ristocetin, binding of the patient's plasma vWF to normal platelets was increased but binding of normal vWF to his platelets was normal. SDS-agarose gel (1.5%) electrophoresis revealed that plasma vWF lacked the large multimers, and 3.0% gel electrophoresis revealed that the multimers had a 5-band pattern similar to normal. The above findings were consistent with type IIB vWD, but 1-deamino[8-D-arginine]-vasopressin (DDAVP) infusion resulted in a shortened BT and the transient appearance of large multimers without a decrease in the platelet count. Family studies revealed that his mother has mild bleeding symptoms, decreased VIIIC, vWF:Ag, and RCof levels and normal to slightly reduced RIPA with a multimer pattern consistent with type I vWD. In contrast, the father, sister, and paternal grandfather were asymptomatic, with a slightly decreased VIIIC level but a normal BT and vWF:Ag and RCof levels. Their RIPA and vWF binding to normal platelets were increased, but unlike the propositus their plasma contained large multimers. We concluded that the propositus is a type IIB-like variant differing from previously reported IIB variants in two ways: 1) his response to DDAVP and 2) a possible double heterozygous mode of inheritance rather than the usual dominant route.
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PMID:A probable double heterozygous type II von Willebrand's disease with increased ristocetin induced platelet aggregation. 160 73

This study was carried out to assess the efficacy of NHS 8Y concentrate in the treatment of patients with von Willebrand's disease (vWD). Eight patients (two type I vWD, one type IIA vWD, two type IIB vWD, and three type III vWD) were treated on a total of 10 occasions with 8Y. Following each treatment episode there was a temporary correction of patients' bleeding time (BT) measurements. Other laboratory parameters--von Willebrand factor ristocetin cofactor activity (vWf:RiCo), vWf antigen (vWf:Ag) levels, and factor VIII coagulant activity (factor VIII:C)--were also corrected. Plasma vWf multimers temporarily reflected those present in the infused concentrate. An effective clinical response was observed in each case despite, as revealed by autoradiography and scanning densitometry of SDS-agarose electrophoresis gels, a reduction in the concentration of the largest vWf multimers in 8Y compared with normal plasma. Overall, the clinical effectiveness of 8Y in vWD was comparable to that seen with cryoprecipitate. We conclude that NHS 8Y concentrate may be used as an alternative to cryoprecipitate for the treatment of vWD.
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PMID:Clinical and laboratory evaluation of National Health Service factor VIII concentrate (8Y) for the treatment of von Willebrand's disease. 211 74

A case of acquired von Willebrand disease (AvWD) associated with an IgA lambda multiple myeloma is reported. No form of inhibitor could be detected. SDS-agarose gel electrophoresis patterns of von Willebrand factor (vWF) both in plasma and platelet lysates were normal but a decrease in all-sized multimers with a type IA pattern was seen. After 1-deamino-8-D arginine vasopressin (DDAVP) infusion, vWF multimers larger than those seen in the resting state appeared in patient plasma, which were progressively cleared. Indirect immunofluorescence studies with a monoclonal antibody to vWF showed that vWF was selectively absorbed into myelomatous cells. This is the first case of AvWD associated with multiple myeloma resulting from the selective absorption of vWF into abnormal plasma cells. This feature established a new pathophysiological mechanism of AvWD in multiple myeloma and probably in other lymphoproliferative diseases.
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PMID:Acquired von Willebrand disease in multiple myeloma secondary to absorption of von Willebrand factor by plasma cells. 220 95

A very rare case with coincidental idiopathic thrombocytopenic purpura (ITP) and familial von Willebrand disease (vWD) was reported. A 23-year-old female was admitted because of unusual bleeding tendency lasting still after the remission of thrombocytopenic state associated with ITP. Coagulation studies indicated the presence of a mild vWD, which was thought to be responsible for the bleeding tendency. The qualitative analysis of von Willebrand factor by crossed immunoelectrophoresis and SDS-1.2% agarose gel electrophoresis showed normal multimeric composition compatible with type I vWD. vWF-inhibitor was negative, and family study revealed that her mother was also affected with type I vWD. These results suggested that there was no immediate causal relation between the two disease states. The prevalence of concomitant disease states with ITP and vWD was discussed.
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PMID:[Coincidental occurrence of idiopathic thrombocytopenic purpura in a patient with familial von Willebrand disease]. 238 Oct 58

We reported a 33-year-old woman with thrombasthenia (type II) in whom 1-deamino-8-D-arginine vasopressin (DDAVP) was available for the hemostasis control during breast tumor resection. She has had recurrent nasal bleeding and purpura since 2 years old. On the first admission to our hospital because of hematuria at 18 years old, she was diagnosed as thrombasthenia (type II) from hemostatic studies. At 20 years old, she had a healthy baby by the cesarean section with transfusion of fresh blood and platelet concentrates. On the 5th admission for the breast tumor resection, defect of glycoprotein II b-III a of her platelets was confirmed by using SDS gel electrophoresis. Recently, there are some reports on availability of DDAVP for hemostatic control in platelet dysfunction of various etiologies as well as mild hemophilia and von Willebrand disease. So, DDAVP (0.4 microgram/kg) was used for hemostasis control. After 1 hour, the bleeding time was shortened from over 10 to 4 min, platelet adhesiveness to glass beads increased from 1.8 to 37%. Furthermore, the levels of Ristocetin cofactor and von Willebrand factor antigen (especially large multimer) also increased. But platelet aggregation with various inducers remained unchanged before and after infusion. Breast tumor (fibroadenoma) resection.
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PMID:[Availability of DDAVP in hemostasis control for the breast tumor resection in a patient with thrombasthenia (type II)]. 238 Oct 63

Two monoclonal antibodies (RFF-VIII:R/1 and RFF-VII:R/2) which recognise the same epitope on von Willebrand factor (vWF) have been used in a simple, two-site, solid-phase immunoradiometric (IRMA) or enzyme-linked assay (ELISA) to analyse vWF in plasma from normal individuals and from patients with von Willebrand's disease (vWD). Results obtained confirm our previous findings (using RFF-VIII:R/2 in a one-site, fluid-phase IRMA) that the MAbs detect the presence of an epitope on the vWF molecule that reflects its function. This epitope is involved in vWF binding to the GPIb protein on platelets. It is reduced in all types of vWD, including type II (or variant) vWD. It is present in normal plasma, in vWF released from normal platelets and from cultured umbilical cord vein endothelial cells. The epitope is, however, found to be reduced in serum. Studies on SDS-treated vWF prove that this GPIb-binding site is dependent on the conformation of the vWF multimers.
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PMID:A two-site, monoclonal antibody-based immunoassay for von Willebrand factor--demonstration that vWF function resides in a conformational epitope. 242 24

Von Willebrand factor (vWf) is the major component of the circulating factor VIII complex. The von Willebrand molecule includes factor VIII related antigen (VIIIR: Ag) which represents the molecular substrate of the von Willebrand activity expressed as Ristocetin cofactor (VIIIR:RCoF) activity. Several methods have been developed for VIIIR: Ag evaluation, among the first being the rocket-immunoelectrophoresis method of LAURELL. Radial immunodiffusion (MANCINI's method) was also used. Subsequently, radioimmunological assays, either as radioimmunoassay (RIA) or immunoradiometric assay (IRMA), were developed with improvements in sensitivity, so that levels of VIIIR: Ag lower than 0.1% of normal can be detected. More recently, an enzyme-linked immunosorbent assay (ELISA), characterized by the use of enzyme-conjugated antibody was proposed. This method shows a sensitivity similar to immunoradiometric methods but without using any dangerous reagent. Finally, a nephelometric method was proposed for factor VIII antigen evaluation. For a qualitative evaluation of von Willebrand factor crossed-immunoelectrophoresis and multimeric analysis can be used. In the first case, the use of precipiting antibodies against von Willebrand factor may demonstrate a peak with different characteristics related to the biochemical property of von Willebrand. Multimeric analysis in SDS-agarose gel electrophoresis followed by staining with labelled antifactor VIII antibodies gives information about different polymeric forms of circulating VIII/vW factor. Von Willebrand factor activity, expressed as its ability to induce platelet aggregation in the presence of the antibiotic Ristocetin, can be carried out using normal formalin fixed platelets, either with aggregometer or visual methods (glass slide test or tubes test and microtritation plate). The corrected evaluation of factor VIII complex by all these techniques together with the clotting activity assay allows a satisfactory study of factor VIII properties.
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PMID:A critical evaluation of the available methods for the determination of factor VIII von Willebrand. 243 33


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