ISSN:1424-8832    

DOI:10.1159/000215128

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Preincubation of rabbit platelet-rich plasma with cocaine hydrochloride, at low and high concentrations, increased the platelet responsiveness to arachidonic acid, in terms of the aggregating response and the thromboxane production. The thromboxane levels released by collagen-stimulated platelets were increased after incubation with low concentrations of cocaine, while marked decreases were observed after incubation with high doses of cocaine. No effects on platelet aggregation induced by collagen and ADP were observed when low concentrations of cocaine were added; on the other hand, high doses of the anaesthetic were found to block the aggregating effects of these two agents. Specific studies showed cocaine to have an inhibitory activity on prostacyclin release when the aortic tissue was mechanically and thermically stimulated. By contrast, the prostacyclin synthesis by ‘exhausted’ aortic rings incubated with arachidonic acid appeared to be enhanced after addition of cocaine. These results lead us to believe that cocaine modifies both the Ca++ membrane binding and the extent of Ca++ influx, thereby increasing the permeability to arachidonic acid and altering the affinity of the membrane binding sites for the aggregating age

ISSN:1424-8832    

DOI:10.1159/000215129

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

We developed a simple technique for the measurement of the procoagulant activity exposed on the surface of macrophages. The cells are isolated, adhered to plastic surfaces, and assayed in the same device. This approach allows us to study the microcoagulation on the surface of intact macrophages by sensitive and specific clotting tests.

ISSN:1424-8832    

DOI:10.1159/000215130

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

The ex vivo effect of oral administration of ticlopidine on rat neutrophil chemotaxis was evaluated. Rats received either 3 oral doses (100 mg/kg body weight) of the drug, within a period of 48 h, via a gastric tube, or the drug was administered in drinking water for 14 days at a dosage of 75 mg/kg/day. Absorption of the drug was manifested by significant inhibition of adenosine diphosphate- (ADP-)induced platelet aggregation. No impairment of neutrophil chemotaxis toward zymosan-activated serum was observed in the ticlopidine-treated animals. These results indicate that concentrations of ticlopidine that significantly inhibit platelet function in rats are without effect on neutrophil chemotaxis toward zymosan-activated serum.

ISSN:1424-8832    

DOI:10.1159/000215131

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

3 individuals from 2 unrelated families with recurrent thromboses and quantitative deficiencies of antithrombin III (AT-III) were treated with danazol, 600 mg daily for 4 months. Significant increases of AT-III (p < 0.025) measured as heparin cofactor activity were noted in 1 female and 1 male patient. Failure to augment levels in the other male patient may have been due to poor absorption of the drug following small bowel resection for mesenteric infarction. Side effects of estrogen deficiency necessitated dosage reduction in the female patient. The 2 males experienced no adverse side effects except for prolongation of the prothrombin time in 1 who was receiving oral anticoagulants. We conclude that danazol causes a significant increase in some individuals with familial AT-III deficiency. Additional studies are necessary to determine whether this form of therapy may prove to be a suitable alternative to long-term anticoagulation and to assess the long-term clinical benefits in individuals with recurrent thrombosis.

ISSN:1424-8832    

DOI:10.1159/000215132

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

On daunomycin treatment of a patient with promyelocytic leukemia, leukocyte elastase appeared in large amounts in the patient’s blood. Also, the plasma fibrinogen was found to be partially degraded to early, X-like, fibrinogen degradation products. These early fibrinogen fragments were isolated and showed a low anticoagulant activity in a thrombin time test. Early fibrinogen degradation products, produced with leukocyte elastase in vitro, have a similar low anticoagulant activity. In contrast, plasmic degradation products inhibit clotting of fibrinogen to a large extent. Although α2-antiplasmin and plasminogen levels were low, antithrombin III levels were not decreased. The low anticoagulant activity of the isolated fibrinogen fragments, the presence of elastase activity in the plasma – both immunological and amidolytical – and the normal levels of antithrombin III suggest that granulocytic enzymes, whose release was enhanced by the cytostatic treatment, were responsible for degradation of fibrinogen in this p

ISSN:1424-8832    

DOI:10.1159/000215133

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Plasma samples from mice bearing the BCL1 leukemia were shown to express elevated levels of neutral proteinase activity when assayed with radioiodinated casein as a substrate. Increased plasma proteinase activity reached levels 3–4-fold higher than controls. The increased levels of activity did not correlate with the degree of hepatosplenomegaly or the number of tumor cells in the blood. The onset of the increase in plasma activity correlated with the onset of the leukemic phase of the disease. These findings with the murine leukemia may be analogous to recent findings of abnormal proteinase activity in plasma from patients with acute leukemi

ISSN:1424-8832    

DOI:10.1159/000215134

出版商:S. Karger AG    

年代:1985

数据来源: Karger

ISSN:1424-8832    

DOI:10.1159/000215135

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Euglobulin fractionation is a frequently employed pretreatment of plasma for the determination of fibrinolytic activity. The fractionation procedure suffers from possible in vitro artifacts, e.g., variable precipitation of C1-inactivator. This is illustrated by the following two situations. It is shown that increased amounts of C1-inactivator not related to an increased plasma concentration are present in euglobulin fractions in cases of classic rheumatoid arthritis. Similarly, postoperatively, a disproportional increase in C1-inactivator in euglobulin fractions occurs. In both cases, an artifically reduced fibrinolytic activity is recorded due to increased inhibition by C1-inactivator. This is circumvented and recognized by adding sodium flufenamate or C1s-esterase to euglobulin fractions to uniformly eliminate C1-inactivator. Two specific assays for tissue-type plasminogen activator activity in euglobulin fractions (as C1-inactivator-resistant activator activity and a parabolic rate assay on a synthetic substrate) correlate excellently (r = 0.8728; p < 0.001; n = 108). The first mentioned is corrected for variable endogenous C1-inactivator; the latter assay is found to be insensitive to inhibition by C1-inactivator. It is concluded that with euglobulin methods a misinterpretation of blood fibrinolytic activity is possible in rheumatoid arthritis patients. In the postoperative period, the fibrinolytic shutdown concerns tissue-type plasminogen activator activity; the pattern of the shutdown can be misjudged in using traditional euglobulin methods.

ISSN:1424-8832    

DOI:10.1159/000215136

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

The response of the fibrinolytic system to hypophysectomy in the rat was studied. 4 and 6 weeks after hypophysectomy the tissue plasminogen activator activity (PAA) was significantly increased in the intima of the aorta, slightly but significantly increased in the renal medulla, and significantly decreased in the vessels of the testis. No change in the PAA of the caudal vena cava, heart, lung and renal cortex was noted. Also, the tissue plasmin inhibition remained unchanged. No effect on the PAA in plasma euglobulin fractions was observed, whereas F VIII was slightly but not significantly decreased 6 weeks after hypophysectomy.

ISSN:1424-8832    

DOI:10.1159/000215137

出版商:S. Karger AG    

年代:1985

数据来源: Karger