摘要:

Abstract:The foetal haemoglobin (HbF) levels and the haplotypes of βschromosomes in sickle cell anaemia patients in Nigeria were evaluated. The mean HbF level was 5.9 ± 3.8% with a range of 0.9–16.7%. 80% of the patients had HbF values below 8% and 94% had HbF levels below 10%. No significant difference in haematological parameters was seen between those with less than 2% HbF and those with greater than 8% HbF. The presence (+) or absence (−) of eight restriction endonuclease enzyme sites within the βsglobin gene cluster (haplotype) on chromosome 11 were mapped. The common haplotype (− − − − + + − +) in 97% of the chromosomes examined closely correlates with the low levels of foetal haemoglobin generally observed in sickle cell patients in the

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00405.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:The circadian and seasonal variations of pretreatment proliferative activity of peripheral blood (PB) as PB S + G2/M‐phase size was determined by flow cytometry in 61 adult patients with acute myeloid leukaemia (AML). Pretreatment PB S‐phase (p<0.002), G2 + M‐phase (p<0.008) and S + G2/M‐phase size are statistically correlated to the time of sampling, with the highest phase size at the end of the day. Time‐variations of the blast cell count are slightly significant (p = 0.049). Cytological diagnosis‐related differences in S + G2/M‐phase (p<0.003) and white blood cell count (p<0.04) time‐variations are observed. For all patients, no seasonal variations can be drawn, but in AML 1 (p<0.029) and AML 4–5 patients (p<0.003), the circadian variations of S + G2/M are affected by the seasons. The present results suggest that time may be taken into account in the monitoring of chemotherapy i

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00406.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:There were 100 patients with pancytopenia notified to the Swedish part of an international study of aplastic anemia (Aa) (1983–1986). Aa was the cause in 16 patients and 50 patients had different conditions explaining their pancytopenia, whereas in 34 patients no obvious explanation was found at the time of discovery of their pancytopenia. A follow‐up study in 1987 comprised the patients with Aa (n = 16) and the patients with uncharacterized pancytopenia (n = 34.3 additional patients had then been diagnosed as having Aa whereas 3 patients had a diagnosis of a low‐grade NHL and 8 patients a diagnosis of MDS. No (or an inadequate) bone marrow sample had been taken in 9 of the 34 patients. This study shows that pancytopenia may be found in many serious conditions. Patients with pancytopenia should be carefully followed as Aa can develop slowly and as the MDS diagnosis can be difficult to establish at an early

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00407.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:We have demonstrated that the intracellular processing of transferrin to effect iron removal involves two pathways, one sensitive to rotenone and the other not. We have also found that the effect of the rotenone is dependent on the transferrin concentration: iron uptake was suppressed with concentrations of transferrin in the micromolar range, and was not suppressed at physiologic concentrations of transferrin. Rotenone does not disturb transferrin's interaction with its extracellular receptor, indicating that its action must be intracellular. The following model is suggested: that separate pathways are entered by transferrin in the cell. The first pathway is preferentially utilized when transferrin is in short supply. It begins with an intracellular site which has a high affinity (and low capacity) for either iron or transferrin. The second pathway begins with an intracellular site which has a high capacity (but low affinity) for either iron or transferrin and is utilized when transferrin is in physiologic concentration (and the low‐capacity, high‐affinity site is saturated); the pathway it initiates is dominant when transferrin is abundant. We speculate that the high‐affinity low‐capacity pathway may serve to direct intracellular iron to sites which would be critically injured by iron

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00408.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:In a retrospective study, 10 patients with smouldering leukaemia (SML) were examined between 1982 and 1987. These patients typically showed the morphological criteria of acute myelogenous leukaemia (>30% blasts in the bone marrow) in most cases together with a long survival time (median 16 months; 5 patients more than 22 months; 5 patients between 2.3 and 6.3 months) without the use of aggressive chemotherapy. At initial diagnosis the blast cell populations of patients with SML were characterized by significantly reduced cytosolic thymidine kinase activity (TK), thymidine‐incorporation (dTR) and deoxyuridine incorporation (dUR) into DNA as well as reduced amounts of DNA‐synthesizing S‐phase‐cells (%S) in the bone marrow (BM), compared to those patients with a rapidly proliferating acute myelogenous leukaemia (AML) and to healthy individuals. None of the SML‐patients showed clinical symptoms such as night‐sweat, weight‐loss, hepato‐ and splenomegaly or lymphadenopathy at initial diagnosis. For characterization of SMLvsAML we recommend the use of the biochemical parameter TK activity and the observed absence of the above‐mentioned clinical symptoms. The transition to the rapidly proliferating type of AML can be recognized by an increase in the values of the biochemical and cytokinetic parameters. The blast count in the bone marrow is not suitable as a diagnostic criterion for the definition of SMLvsAML or its transition to the rapidly prolifer

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00409.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:Congenital heterozygous dysfibrinogenemia was diagnosed in a young woman with bleeding tendency. 3 other asymptomatic members of her family (mother and the 2 sisters) had abnormal fibrinogen. The proposita's plasma exhibited prolonged thrombin and reptilase times. Plasma fibrinogen concentration determined by functional assay was 0.3 g/l, whereas immunologic assay revealed normal fibrinogen levels. Turbidity curves, representing the rate of thrombin‐induced fibrin formation, were markedly delayed both in the presence and absence of Ca2+. Isoelectric focusing and SDS electrophoresis of reduced fibrinogen showed normal charge and size of the subunit chains. Release of fibrinopeptide B by thrombin was normal, whereas HPLC elution diagrams of fibrinopeptide A showed an abnormal peak A* with a slightly shorter retention time than the normal fibrinopeptide A. The amino acid analysis showed that the arginine in peak A* is replaced by histidine (Aα 16 Arg →

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00410.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:The iron‐binding glycoprotein lactoferrin binds to specific receptors on human monocytes as an initial step implicated in monocytic iron deposition. In this study, the properties of lactoferrin were studied after its interaction with human monocytes. Rebinding of lactoferrin to its monocytic receptor was grossly impaired and a small decrease in isoelectric point from 8.9 to 8.8 was observed. In contrast, antigenic and iron‐binding properties of lactoferrin were preserved, the molecular weight by SDS‐polyacrylamide gel electrophoresis was unchanged and no low‐molecular fragments were detected by gel‐filtration. These findings indicate that lactoferrin molecules cannot operate in a cyclic manner to deposit iron. Furthermore, these results might contribute towards explaining the complex disappearence kinetics observed for lactoferrin

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00411.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:Our study shows that the thrombocytopenia described in type IIB von Willebrand's disease (vWd) after 1‐desamino‐8‐D‐arginine vasopressin (DDAVP) infusion is, at least partially, a pseudothrombocytopenia. There was a discrepancy in platelet counts in blood anticoagulated with EDTA (<10 times 103/μl) or citrate (55 times 103/μl) in one patient with type IIB vWd and chronic thrombocytopenia (80 times 103/μl) after DDAVP infusion. Furthermore, DDAVP induced a normalization of patient's prolonged bleeding time. Spontaneous platelet aggregation (SPA) observed in platelet‐rich plasma before DDAVP infusion was inhibited completely by monoclonal antibodies which block binding of fibrinogen, vWf and fibronectin to GPIIb‐IIIa. SPA was partially inhibited by a monoclonal antibody which blocks the binding of vWf to GPIb. After DDAVP, in contrast, SPA partially persisted in the presence of anti‐GPIIb‐IIIa monoclonal antibodies but was completely inhibited by anti‐GPIb monoclonal antibody. Therefore GPIb and GPIIb‐IIIa complex seem to play a different role in SPA before and after DDAVP infu

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00412.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:To help understand the pathogenesis of megaloblastic anaemia, we have studied folate‐deprived HL60 cells. Cells grown with no added folic acid developed macrocytosis, a prolonged doubling time, a grossly increased deoxyuridine‐suppressed value, and markedly reduced thymidylate synthetase activity. Cells in medium containing 50 nmol/l added folic acid became macrocytic with similar biochemical changes, but their doubling time was only marginally prolonged. In 100 nmol/l added folic acid, there was slight macrocytosis and a normal doubling time, but marked biochemical alterations were still present. The findings demonstrate that folate deficiency causes diminished thymidylate synthetase activity and macrocytosis in human myeloid cells, but that such cells may nevertheless demonstrate no prolongation of their doubling time, indicating either that their supply of thymidine triphosphate (TTP) is sufficient, or that mis‐incorporation of deoxyuridine triphosphate (dUTP) is occurring. This suggests that the ineffectiveness of haemopoiesis in folate deficiency may result from damage to bone marrow cells in some way other than arrest in S‐phase by a reduced delivery of TTP to the DNA replicati

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00413.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:The plasma level of tissue plasminogen activator antigen (t‐PA‐Ag) was examined in 86 patients with polycythemia (29 polycythemia vera, 11 secondary polycythemia and 46 with spurious polycythemia) and 24 healthy volunteers. Tissue plasminogen activator antigen was significantly decreased in patients with polycythemia vera in comparison with healthy controls. On the other hand, in patients with spurious polycythemia and secondary polycythemia t‐PA‐Ag concentration was significantly increased. There was no significant difference in t‐PA‐Ag levels in polycythemic patients with or without thromboembolic disease. A significant correlation was detected between t‐PA‐Ag level and hemoglobin or hematocrit concentration in patients with polycythemia vera (p = 0.02, r = 0.43). However, in patients with secondary polycythemia and spurious polycythemia, no significant correlation between t‐PA‐Ag and hemoglobin level was found. Plasminogen activator inhibitor (PAI) levels in patients with polycythemia vera and healthy volunteers did not d

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00414.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY