摘要:

AbstractProstacyclin (PGI2) is a well‐known potent inhibitor of platelet aggregation. Its role has been implicated in physiological and pathological states of hemostasis. Heparin blocks the prostacyclin‐mediated antiaggregatory activity on platelets. Prior treatment of heparin with heparinase as well as with protamine destroyed heparin's ability to neutralize PGI2. Studies on the mechanism of heparin blocking of PGI2activity suggested that heparin interacted directly with PGI2, as shown by the loss of PGI2mobility on thin layer chromatography concomitant with the loss of PGI2‐mediated inhibition of platelet aggregation. PGI2in this combination with heparin, nevertheless, retained its time‐dependent ability to be hydrolyzed to 6‐keto‐PGF1α. Findings of these studies may have implications in thrombosis and hemostasis, particularly in heparin‐mediated abnormalities of circula

ISSN:0361-8609    

DOI:10.1002/ajh.2830200202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe effect of parenteral calcium on altering the activity of factor VIII inhibitors has been studied in three patients, two nonhemophiliacs and one hemophiliac. The patients were studied during both intravenous calcium infusion, factor VIII replacement, and combinations thereof. When compared to factor VIII replacement alone, a greater diminution of inhibitory activity was noted whenever calcium was infused prior to and during factor VIII replacement. This was demonstrated by both conventional coagulation assays and an agarose gel method. These observations could have therapeutic implications and may aid in further understanding the relationship of calcium to factor VIII and its inhibitor.

ISSN:0361-8609    

DOI:10.1002/ajh.2830200203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractPeripheral blood mononuclear cells from 11 patients with remission Hodgkin disease and 20 normal controls were incubated with irradiated allogeneic lymphocytes in oneway mixed lymphocyte cultures. Simultaneously, modified assays were performed by adding supplemental irradiated PBM, T lymphocytes, or adherent cells autologous to the responders. Baseline allogeneic responsiveness of patients and controls was not different. However, significant suppression (p<.01) was demonstrated when the cultures were supplemented with patient mononuclear cells or adherent cells, an effect not found with similar supplemental cells from controls. Conversely, T‐cell supplementation of control cultures produced more than twofold increases in proliferation but significantly less augmentation in the patients' cultures (p<.01). T‐cell subset analysis in six patients showed decreased helper:suppressor cell ratios. Hodgkin disease patients have adherent suppressor cells, which persist during remission, as well as a defect in T‐cell helper fun

ISSN:0361-8609    

DOI:10.1002/ajh.2830200204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractHuman T‐cell leukemia virus (HTLV‐I) is known to be associated with certain hematologic malignancies, and a related virus, HTLV‐III/LAV, might be the cause of AIDS. Some persons with AIDS have had evidence of HTLV‐I infection. Unrelated to these findings, it has been suggested that HTLV‐I is transmitted via blood products. We therefore evaluated the serologic status to the HTLV‐I core antigen p24 of 48 persons with hemophilia (Hem A) receiving factor concentrate therapy (a group at risk for AIDS), 49 persons with β‐thalassemia major (Thal) receiving frozen packed red blood cells therapy (FPRC), 26 patients with sickle cell anemia (SCA) receiving FPRC, and 18 persons not receiving any blood products. All participants were clinically well; only one had a risk factor other than hemophilia for AIDS, and all were from New York City, an area with a high incidence of AIDS. No Hem A or nontransfused persons had serum antibody to HTLV core p24 antigen; three with Thal and one with SCA were antibody‐positive. These results were confirmed by both radioimmunoprecipitation and Western blot techniques. Positive serology did not correlate with any immune findings or quantity of blood products used. These data support that HTLV‐I is preferentially transmitted through cellular blood products and that it is an infection for which cellular blood product recipients in at least some areas of the United States are at risk. Concentrate products appear free of transmission risk relative to cellular blood products, but we cannot be certain that this safety is absolute. The public health implications of blood product transmission of HTLV‐I merit active, lon

ISSN:0361-8609    

DOI:10.1002/ajh.2830200205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe incidence of deficiency of the enzyme pyruvate kinase (PK) in Chinese infants was determined. Both the standard assay of erythrocyte pyruvate kinase enzyme activity and a fluorescent screening test (standardized) were used. The results of these two tests were compared. Of 1,159 infant cord blood samples studied, 26 (or 2.2%) had abnormally low levels of PK activity using the screening test, as did 24 of the samples tested by the enzyme assay. The results indicate that the frequency of a defective PK gene in the population of Guangzhou is significantly lower (p<.05) than the previously reported defective gene frequency of 3.4% in Hong Kong. They also demonstrate the critical importance of standardization of the screening test, if most accurate estimates of gene frequency are to be derived by using this test.

ISSN:0361-8609    

DOI:10.1002/ajh.2830200206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe enzyme activities of cultured early erythroid progenitor cells (burst‐forming unit erythroid, BFU‐E) were measured and were compared with the activities of mature erythrocytes. The enzyme activity of acetylcholinesterase was not detectable in the erythroblasts. The ratios of phosphofructokinase and glutathione peroxidase were low due to low enzyme activities in both the erythroblasts and erythrocytes. The ratios of triose phosphate isomerase, phosphoglycerate kinase, and adenylate kinase were low due to high enzyme activities in both the erythroblasts and erythrocytes. The ratios of hexokinase, glucose phosphate isomerase, monophosphoglyceromutase, pyruvate kinase, and adenosine deaminase were high due to high enzyme activities in the erythroblasts.The isozyme of erythroblast hexokinase was of the prototype isozyme I, while pyruvate kinase was predominantly of the prototype M2, with two hybrid isozymes to the anodal side by electrophoresis. These facts suggest that there is a greatly different metabolic pattern during the maturation of the erythroid ce

ISSN:0361-8609    

DOI:10.1002/ajh.2830200207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe use of volatile butylnitrite in place of sodium nitrite for the in vitro production of methemoglobin was explored in studies of G6PD‐deficient red cells and for measurements of the red cell methemoglobin reductase activity. It was found that butylnitrite vapor caused a more rapid oxidation of intracellular hemoglobin than sodium nitrite and required fewer washes for removal. Hence a more rapid preparation of the cells was possible. Both cytochemical detection of G6PD‐deficient cells in a female heterozygote for G6PD deficiency and the screening test for a methemoglobin reductase deficiency could be performed with butylnitrite as well as with sodium nitrite. This small modification of these standard procedures promises to save time and facilitate processing of many samples during genetic screening of relevant populati

ISSN:0361-8609    

DOI:10.1002/ajh.2830200208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractA patient with thrombotic thrombocytopenic purpura (TTP) responded transiently to four courses of plasma exchange therapy, then subsequently had a sustained completed remission following splenectomy. The von Willebrand factor multimeric pattern during remission following each plasma exchange and during the entire postsplenectomy period showed abnormally large forms that were not present on presentation and with each clinical relapse. These findings support prior observations regarding the presence of abnormal von Willebrand factor multimers in relapsing TTP and suggest that the multimers contribute to platelet aggregation and the thrombotic lesions. The association of sustained remission and persistence of the abnormally large plasma multimers after splenectomy suggests that this response was not coincidental. This supports the concept that a subgroup of patients with TTP may exist in which the pathophysiology of disease is significantly modulated by the spleen and in which splenectomy may induce long‐lasting remissio

ISSN:0361-8609    

DOI:10.1002/ajh.2830200209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe effect of infusing DDAVP and cryoprecipitate either singly or in combination was studied in a patient with variant von Willebrand disease. Both DDAVP and cryoprecipitate caused only partial correction in the hemostatic defect when used as a single agent. A combination of DDAVP and cryoprecipitate induced a complete correction of the hemostatic defect as well as factor VIII related properties.

ISSN:0361-8609    

DOI:10.1002/ajh.2830200210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractA case study is presented of a leukemic patient whose cells express markers of both myeloid and lymphoid cells. Cells were identified from bone marrow which expressed either myeloid antigens, lymphoid antigens, or both myeloid and lymphoid antigens, indicating a possible common stem cell capable of differentiating along either a lymphoid or myeloid cell lineage. Using specific monoclonal antibodies, 40‐70% of the cells were reactive with anti‐T‐cell antibodies, 50% of the cells were reactive with antibodies to the common ALL antigen (CALLA), and 80‐90% of the cells were reactive with antibodies directed against myeloid antigens. Using double staining techniques, some cells were found to demonstrate only myeloid markers; others, only lymphoid markers; and others, both myeloid and lymphoid markers. These results suggest that a common stem cell is capable of differentiating along both lymphoid and myeloid l

ISSN:0361-8609    

DOI:10.1002/ajh.2830200211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY