摘要:

Preliminary epidemiological data showed a high but varying prevalence of factor V Leiden mutation in various European populations. To analyze population differences statistically and generate reliable evaluation criteria for morbidity estimates, large numbers of unselected probands from different populations have to be tested. A convenient, efficient, reliable and cost efficient method for large-scale screening of factor V Leiden mutation has been developed using capillary blood samples soaked onto filter paper cards for the detection of mutations by heteroduplex analysis. Screening 1,628 alleles of a north-eastern German population by this procedure revealed an allele frequency of 3.56% (carrier rate 7.12%) which is significantly higher than those published for Italy and the Netherlands. Differences in allele frequencies compared to other European populations could statistically not be proved based on the small size of the published samples.

ISSN:1424-8832    

DOI:10.1159/000217213

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Despite adjunctive therapy with heparin and aspirin, patients undergoing percutaneous transluminal coronary angioplasty (PTCA) continue to be at risk of abrupt vessel closure and acute ischaemic events. In an attempt to overcome the limitations of traditional antithrombotics, more potent agents have been developed, including direct thrombin inhibitors (e.g., hirudin and hirulog) and new antiplatelet agents [e.g., the gly-coprotein Ilb/IIIa receptor inhibitor c7E3 Fab (ReoProTM)]. Initial phase-III trials of hirudin in patients with acute coronary syndromes identified an excess incidence of major bleeding complications. Some of these trials have been recommenced using lower doses. Reports on phase-III trials of hirulog should be forthcoming soon. Of the new agents, the chimeric monoclonal antibody fragment c7E3 Fab has the most extensive available data. In the phase-III evaluation of 7E3 for the Prevention of Ischemic Complications trial, the administration of a c7E3 Fab bolus plus c7E3 Fab infusion reduced the rate of major ischaemic events by 35% at 30 days (p = 0.008) in patients undergoing high-risk PTCA. Major bleeding episodes occurred more frequently with this regimen than with placebo, although rates of intracranial haemorrhage or surgery for bleeding did not differ between groups. The findings suggest that the risk of bleeding complications might be reduced, without compromising efficacy, by administering heparin on a weight-adjusted basis in patients treated with c7E3 Fab.

ISSN:1424-8832    

DOI:10.1159/000217214

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

The aim of the present study was to gain clinical experience with different dose levels of dalteparin, a low-molecular-weight heparin, following thrombolytic therapy in acute myocardial infarction. Compared to heparin, dalteparin has a longer half-life and a greater and highly predictable bioavailability, which would suggest dalteparin to be a convenient alternative. Twenty patients with ECG signs of acute transmural myocardial ischemia received streptokinase (1.5 million IU for 60 min) and were allocated to a control group or to open treatment with 50, 75 or 100 IU of dalteparin/kg b.w. s.c. b.i.d., starting 4 h later, for 6 days. Each group consisted of 5 patients. Except for the control group, aspirin was withheld during dalteparin treatment. Anti-factor-Xa (anti-FXa) values increased dose-dependently during the first 24 h and were maintained throughout the study period. On day 6, anti-FXa levels after 100 IU/kg b.w. were 0.79 (0.59-1.00) IU/ml (median, min.-max.) 4 h after administration of dalteparin, and 0.51 (0.34-0.82) IU/ml before the subsequent dose of dalteparin. In conclusion, our results indicate that a dalteparin dose slightly higher than 100 IU/kg b.w. is required in order to obtain the presumed therapeutic range of anti-FXa (0.6-1.0 IU/ml).

ISSN:1424-8832    

DOI:10.1159/000217215

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Hydroxyethyl starch (HES) with a high or medium molecular weight (MW) and a high degree of substitution is difficult to degrade and leads to an accumulation of large molecules. These molecules have a negative effect on hemostasiological parameters. In 10 patients with cerebrovascular diseases, a hemodilution therapy was carried out with low MW HES for 10 days. Due to the low MW of the HES used (56-61 kD), the rheological parameters erythrocyte aggregation and plasma viscosity were significantly lowered (p < 0.01). No coagulation parameters studied were affected beyond the dilution effect, which was measured using the decline in hematocrit. Low MW starch is a volume substitute that is well-suited for repeated infusion or hemodilution therapy, particularly for patients with increased hemorrhagic diathesis, because it does not affect hemostasis. The disadvantage of a relatively short volume effect can be compensated through a continuous infusion of a larger volume.

ISSN:1424-8832    

DOI:10.1159/000217216

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

The standardization of prothrombin time (PT) assays needs two steps: (1) calibration of PT assays towards a reference assay or reference thromboplastin, (2) correction of PT assays according to the calibration. The present recommended calibration by clotting times is favored for the linearity between assays; the clotting times of abnormal plasma are partly prolonged due to the protein induced by vitamin K absence (Pivka) inhibitor. Calibration by coagulation activities also demonstrated linearity between PT assays; the regression line for abnormal plasma deviated from the line of identity due to differences in sensitivity of assays for the Pivka inhibitor. The corrected PT assays demonstrated similar results using calibration by clotting time or coagulation activities, but the correction was simpler for coagulation activities. Patient plasma was the preferable material in calibration by clotting times as well as by coagulation activities. The corrections between the reference assay and other PT assays were equal to the differences in sensitivities for the Pivka inhibitor. The corrected PT assays did not differ from the reference assay by statistical analysis; any of the six PT assays tested might be used as reference assay.

ISSN:1424-8832    

DOI:10.1159/000217217

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Automatized platelet parameters were evaluated in 23 unselected patients undergoing a bone marrow examination for diagnostic purposes, both in medullary and in peripheral blood, with the aim of investigating the biological significance of platelet volume heterogeneity. In the marrow blood the platelet count was 10.07 ± 21.25% (p < 0.05) lower and the platelet volume 7.93 ± 6.88% (p < 0.001) higher compared to peripheral venous blood: 275,173 ± 108,079 versus 296,652 ± 104,814/mm3 (p < 0.05) and 8.93 ± 1.46 versus 8.23 ± 1.57 f1 (p < 0.001), respectively. The same behavior was observed between the marrow and the arterial blood collected from 12 out of the 23 patients, while no significant difference was observed between arterial and venous blood. The differences observed might be attributable to a platelet population replacement under homeostatical regulation and seem to support the concept that the large platelets are younger ele

ISSN:1424-8832    

DOI:10.1159/000217218

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Alterations in the plasma levels of tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI-1) as observed in various liver disorders are attributed to deranged liver function. Status of these parameters in patients with Budd-Chiari syndrome (BCS) has not been reported so far. In the present study 27 patients with BCS with hepatic and/or inferior vena cava occlusion were investigated for any defect in the fibrinolytic system. Mild to moderately deranged liver function tests were observed in all (except 2) patients. Three patients each showed mildly increased levels of t-PA (3/27) and PAI-1 (3/27). The levels of t-PA and PAI-1 however did not show any correlation with liver function parameters.

ISSN:1424-8832    

DOI:10.1159/000217219

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:1424-8832    

DOI:10.1159/000217220

出版商:S. Karger AG    

年代:1996

数据来源: Karger