Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002874 (aplastic anemia)
 5,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We tested an in vitro system simulating bleeding time reported by Kratzer et al. Primary hemostasis was studied perfusing an artificial vessel with citrated blood under a constant pressure of 40 mmHg, measuring the blood volume perfused (bleeding volume) and the time until blood flow stopped (bleeding time). The artificial vessel consists of a glass capillary simulating arteriole and a filter covered with collagen type I to provide a surface for the adhesion of platelets. The bleeding volume (mean +/- SD microliters) was 317.7 +/- 93.8 in controls (n = 19), 487.3 +/- 242.1 in idiopathic thrombocytopenic purpura (n = 9), 666.8 +/- 224.1 in aplastic anemia and paroxysmal nocturnal hemoglobinuria (n = 4), greater than 820 in von Willebrand's disease (n = 3), 231.0 +/- 74.5 in hemophilia A (n = 3), 499.0 +/- 269.4 in liver cirrhosis (n = 6), and 457.7 +/- 229.0 in myeloproliferative disorders (n = 11). When citrated blood was applied to this system after incubation with monoclonal antibodies (MoAb) to von Willebrand factor or platelet membrane glycoprotein Ib (GPIb), bleeding volume was significantly increased while no effects were observed after incubation with MoAb to GPIIb/IIIa, factor VIII: CAg and factor XIIIa. These data suggest that in vitro model of primary hemostasis could be used for not only diagnosing bleeding disorders although 'time' is not reliable, but also investigating the mechanisms of hemostasis.
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PMID:[Bleeding time and volume in vitro by THROMBOSTAT]. 231 3

In some patients with thrombocytopenia, it is difficult to determine whether the condition is caused by underproduction of platelets (reduced numbers of megakaryocytes) or an increase in the rate of their destruction (normal or increased numbers of megakaryocytes). A non-invasive test to help distinguish between these two categories of thrombocytopenia would be useful. We related the plasma concentration of glycocalicin, a fragment of the platelet-membrane glycoprotein Ib, to the mechanism of thrombocytopenia by evaluating bone marrow megakaryocyte content and measuring platelet life span. Plasma glycocalicin was measured with a monoclonal antibody to the glycocalicin component of platelet glycoprotein Ib. The mean (+/- SD) plasma concentration of glycocalicin in 34 healthy controls was 87 +/- 20 percent of the level in pooled normal plasma (range, 52 to 127 percent). All of eight patients with aplastic anemia or amegakaryocytic thrombocytopenia confirmed by examining bone marrow (in all patients) and by determining the life span of autologous platelets (in six patients) had glycocalicin levels significantly below the normal range (5 to 27 percent). In contrast, each of 25 patients with thrombocytopenia thought to be caused by a reduction in platelet life span, whose bone marrow contained normal or increased numbers of megakaryocytes, had glycocalicin levels that fell within or above the normal range (48 to 261 percent). There was no overlap of values between the two patient populations. These studies indicate that the measurement of plasma glycocalicin may be a useful adjunct in classifying thrombocytopenic disorders.
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PMID:Plasma glycocalicin. An aid in the classification of thrombocytopenic disorders. 365 67

To aid in the rapid differential diagnosis of thrombocytopenia, the authors developed a latex agglutination test for glycocalicin, a proteolytic fragment of platelet membrane glycoprotein Ib. Plasma glycocalicin determinations were performed for 34 patients with thrombocytopenia. Plasma samples from four patients with aplastic anemia and ten patients with myelodysplastic syndromes, all with glycocalicin levels less than 0.6 mg/L by an enzyme-linked immunosorbent assay, all had negative results by the latex test. In contrast, positive latex agglutination titers were obtained for all 12 patients with idiopathic thrombocytopenic purpura. Eight patients with liver cirrhosis and splenomegaly had elevated levels of plasma glycocalicin, and all of their plasma samples produced agglutination. This latex agglutination test for glycocalicin allows a rapid discrimination of thrombocytopenia caused by impaired platelet production from that caused by increased platelet destruction; thus, it is suitable for use as a screening test in a routine clinical laboratory.
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PMID:Rapid detection of plasma glycocalicin by a latex agglutination test. A useful adjunct in the differential diagnosis of thrombocytopenia. 824 98

The aim of this study was to explore application value of detecting platelet associated antibody and platelet membrane glycoprotein in the diagnosis and prognosis for immune thrombocytopenia. The platelet associated immunoglobulin (PAIg) and platelet membrane glycoprotein (CD41, CD61, GPIIb/IIIa) in 76 cases of immune thrombocytopenia and 30 healthy subjects were determined by FCM. The results showed that PAIg level in ITP patients included PAIgG (31.25 +/- 18.06)%, PAIgM (32.41 +/- 15.51)%, PAIgA (23.39 +/- 16.67)% which were remarkedly higher than in health control (10.48 +/- 5.05)%, (9.40 +/- 4.42)% and (7.23 +/- 3.61)% (P < 0.001). In patients with secondary immune thrombocytopenia (chronic aplastic anemia, SLE, Evans syndrome, liver cirrhosis hypersplenism, etc), PAIg level was higher than that in control group, while the platelet membrane glycoprotein in the blood of these patients was lower than that in control group. The level of PAIg decreased (P < 0.05) after treatment, but platelet membrane glycoprotein increased (P < 0.01). The result suggested that measurements for platelet membrane glycoprotein and platelet associated antibody by FCM were practical with high sensitivity, rapidity and simplicity used as a routine method in diagnosis and evaluation of the therapeutic effects in immune thrombocytopenia patients.
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PMID:[Significance of detecting platelet associated antibody and platelet membrane glycoprotein for diagnosis of immune thrombocytopenia]. 1515 39