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Biomedical subjects

M L Wiesel

Publications and source records attributed to M L Wiesel.

66 records · Page 4Linked to original sources

Biological and clinical heterogeneity of lupus and lupus-like anticoagulant in fifty-seven patients.

A lupus or lupus-like inhibitor was detected in 57 patients: 24 systemic lupus erythematosus, 9 autoimmune diseases, 10 lymphoproliferative disease, 11 miscellaneous diseases and 3 asymptomatic patients. No hemorrhagic diathesis was observed in spite of major surgery. Thromboembolism occurred in 19 patients. Among them, 5 patients had recurrent abortions. An extensive study of coagulation profile compared different assays to investigate lupus-like inhibitor: the most sensitive assay was the partial thromboplastin time performed without activator. When performed with kaolin, it was the only assay detecting the lupus cofactor. Prothrombin time was prolonged in only 53% of the patients. Factors VIII, IX, XI and XII were in the normal range in 40% of the patients. When decreased, apparent deficiencies were usually not detectable on further dilutions of the test samples. In 7 patients factor XII antigen and activity were both decreased, suggesting an apparent factor XII deficiency. No relationship was observed between thromboembolic events, underlying disease or biological pattern.

Adolescent↗

An IgM lupus anticoagulant that neutralizes the enhancing effect of phospholipid on purified endothelial thrombomodulin activity--a mechanism for thrombosis.

An anticoagulant activity was isolated from the plasma of a patient with a strong lupus-like anticoagulant using gel filtration by high performance liquid chromatography. IgM were detected in this anticoagulant fraction which exhibited specificity towards 50% phosphatidylcholine - 50% phosphatidylserine vesicles and cardiolipin. These phospholipids were able to produce an apparent 3-fold enhancement of purified human protein C activation by human alpha-thrombin in the presence of purified human placenta thrombomodulin. In the absence of phospholipid, the anticoagulant fraction had no effect on thrombomodulin activity. The anticoagulant fraction could neutralize the enhancement of thrombomodulin activity by phospholipid in a dose-dependent manner. This study suggests that the neutralization of phospholipid might result in a reduced activation of protein C which could be responsible for the occurrence of thrombotic complications in a proportion of patients with lupus anticoagulants.

Aged↗

[Hereditary antithrombin III deficiency causing recurrent thrombo-embolic problems (author's transl)].

A marked deficiency in antithrombin III (AT III) was demonstrated in a 39-year-old man suffering from recurrent thrombo-embolic problems. The patient's father had died following a thrombo-embolic disorder. A certain number of members of the family also showed evidence of a marked decrease in AT III levels. Although it was not possible to study the patient's parents, it would seem reasonable to conclude that the diagnosis was one of hereditary deficiency in AT III. The various aspects of this disorder discovered by Egeberg are reviewed: early onset, in several members of the same family, or recurrent thrombo-embolic problems, accompanied by a decrease in functional activity of one of the principal inhibitors of thrombin (AT III), with autosomal dominant transmission and treatment based upon anti-vitamin K agents.

Adult↗

[Cerebromeningeal hemorrhages and their sequelae in congenital deficiencies of plasma hemostasis factors. Apropos of a case of Stuart factor deficiency with early cerebromengeal hemorrhage leading to hydrocephalus with considerable psychomotor retardation].

We have taken an interest in cerebro meningeal haemorrhages in congenital plasmatic coagulation Factor deficiency with out obvious traumatic origin. We have observed such accidents in a new born child with congenital Stuart factor deficiency and in four cases of haemophilia A. It seems from our experience and from the literature that such haemorragic accidents are not particularly frequent in congenital coagulation deficiency and contribute only for a few to creation of a psychomotor inadapted population.

Cerebral Hemorrhage↗

[Antiphospholipid antibodies (aPL): detection and clinical significance].

Phospholipid-binding antibodies are heterogeneous immunoglobulins of G and/or M and/or A class which can be detected in association with a variety of pathologies. However they can also occur in the absence of any clinical manifestations. Despite their paradoxical in vitro anticoagulant activity, phospholipid-binding antibodies, either primary or secondary, are frequently associated with venous and/or arterial thrombotic events. Hence, their detection has to be performed in several major clinical situations, cerebral attack, myocardial infarction, recurrent fetal loss, deep vein thrombosis ... Their course has to be controlled at least every six months. Since the incidence of phospholipid-binding antibodies in auto-immune pathologies is high, immunological disorders should also be considered. As yet there is no standardized assay of phospholipid-binding antibodies, either functional with respect to their anticoagulant activity, or immunological (ELISA). It is not established whether they possess an own pathogenic potential or appear as a secondary response following cellular alterations known to be thrombogenic. However it has been suggested that they could participate in the disruption of the hemostatic balance towards procoagulant tendency resulting in thrombosis.

Antibodies, Anticardiolipin↗

[Congenital deficiencies of natural anticoagulant systems responsible for recurrent thromboembolism].

The main characteristics of the blood coagulation system is its high potential of autoamplification. Cascade reactions consisting of successive activations of zymogens into their respective serine-proteinase active form culminate in the generation of thrombin, the central enzyme of the system. Blood coagulation is under control of two major natural regulatory mechanisms limiting the extension of the thrombus. The first one with antithrombin III as the central element, directly inhibits thrombin and other activated clotting factors in cooperation with heparans synthetized by the vascular wall. The second one, the protein C pathway, limits thrombin generation, through its ability to block the amplification potential of feedback reactions. The physiological significance of these regulatory mechanisms is clearly emphasized by the frequency of recurrent thrombotic episodes affecting subjects presenting an inherited deficiency of one of these components, estimated between 50 and 70%. Patients with protein S deficiency, the essential cofactor of activated protein C, exhibit a surprisingly high tendency to arterial thrombosis. The biological investigation of thromboembolic disease must be focused on antithrombin III, protein C and protein S deficiency using functional assays when available or feasible in order to detect both qualitative and quantitative defects.

Antithrombins↗

[Gray platelet syndrome].

BACKGROUND: Gray platelet syndrome is a rare (about 40 cases published), inherited disorder characterized by a marked decrease or absence of platelet alpha-granules and platelet specific alpha-granule proteins. CASE REPORT: A boy, aged 4 years, presented with frequent ecchymoses. Acute idiopathic thrombocytopenia purpura was diagnosed because of his reduced platelet count (36,000/mm3) and recent viral infection. Intravenous gammaglobulin infusion was followed by a small rise in the platelet count (125,000/mm3). The patient was reinvestigated a few months later because of persistent thrombocytopenia and the failure of the immunologic treatment. The bleeding time was long and the platelets on blood smears appeared gray. Electron microscopy revealed numerous vacuoles and very few or no alpha-granules. Platelet aggregation and adhesion were normal, but stimulated platelets failed to liberate factor 4 and beta-thromboglobulin, while the plasma levels of beta-thromboglobulin were elevated. CONCLUSION: The frequency of gray platelet syndrome is probably underestimated in those diseases resulting in thrombocytopenia and this will continue until blood smears are thoroughly examined. Synthesis of platelet specific alpha-granule proteins seems normal; but these proteins cannot be stored as there are very few, or no alpha-granules. This abnormality could lead to increased levels of such proteins in the plasma.

Blood Platelet Disorders↗

[Importance of disorders of primary hemostasis in the occurrence of upper digestive hemorrhage in cirrhosis].

In order to assess the true incidence of haemostatic disorders in cirrhotic gastro-intestinal haemorrhage, a comparative prospective study of primary haemostasis, coagulation and fibrinolysis was carried out in 37 patients distributed into two groups: cirrhotics with gastro-oesophageal varices that had never bled (Group A = 22), and cirrhotics who had had an intestinal bleed from "ruptured" gastro-oesophageal varices (Group B = 15). Combination of thrombocytopenia (less than 100 10(9)/l) and a bleeding time greater than 8 mn was more frequent in Group B (80%) than in Group A (45%) (p = less than 0.05). On the other hand, no significant difference between the two groups was found in the activated cephalin time, thrombin time, prothrombin complex factors (II, V, VII-X), fibrinogen, antithrombin III, Factor VIII complex factors, FDP levels or plasminogen. In conclusion, these results suggest that disorders of primary haemostasis may be involved in bleeding from gastro-intestinal varices in cirrhosis. However, coagulation disorders and anomalies of fibrinolysis would not seem to play a determining role.

Bleeding Time↗

[Surgical correction of interventricular communication with pulmonary stenosis in a hemophiliac].

Open heart surgery was performed in a 5 year-old boy with severe hemophilia A and large ventricular septal defect with pulmonary stenosis. High doses of Factor VIIIC superconcentrates delivered as small transfusion volumes allowed the use of extracorporeal circulation with heparin. Transfusions began 5 hours before surgery and were stopped 21 days later. No adverse reaction was observed. Thus major surgery is possible in severe hemophiliacs provided strict rules for replacement therapy are followed.

Child, Preschool↗