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Biomedical subjects

J F Stoltz

Publications and source records attributed to J F Stoltz.

At least 199 records · Page 11Linked to original sources
PubMed1980

[Anti-varicella-zona immunoglobulins. Discovery of antibodies and method of formation].

The screening of zoster's antibodies has been performed in blood donors population and persons convalescing from herpes zoster. The results show that 25% of blood donors and 83,5% of convalescents have respectively a titer of CF antibody of 8. Plasma units were pooled and the pool had a final titer of CF antibody of 16. Varicella zoster immunoglobulin prepared by alcohol fractionation had a fluorescent antibody titer of 1 024 and a CF antibody of 512. These results are discussed and compared with those of literature.

Adult↗
PubMed1980

[Influence of microaggregate transfusion filters on the rheological properties of blood].

Micro-aggregate transfusion filters have been suggested in order to prevent pulmonary complications in cases of shock after massive transfusions and cerebral complications after ECC. It is important to have prior knowledge of performance, in particular with regard to perfusion flow rate and the efficacy of filtration. Eight filters have been thoroughly studied: Bentley PF 127, Bentley PFF 100, Biotest, Fenwal 4C2417, Fenwal 4C 2423, Intersept, X Pall Ultipor SQ 40 S, Swank IL 40 S. For each of them, study included the following: perfusion flow rate, filtration pressure (Swank technique) of whole blood distal or proximal to the filter, viscosity and various haematological parameters (CBC, free haemoglobin, red cell ATP). Finally, the deposit retained by the filter must be studied morphologically by sweep electron microscopy. It would seem that good aggregate elimination power (decrease in filtration pressure of 75 to 95 per 100) often coincides with a poor flow rate and the need to rapidly change the filter. Efficacy is virtually the same for all filters with the exception of Pall filter where it seems to be less. The Bentley PF 100 and Fenwal 4C 2423 filters combine this efficacy with an adequate flow rate, resulting in easy use in practice. By contrast, the Pall filter with a very satisfactory flow rate is less effective than the other with regard to the retention of aggregates. Other parameters are only very slightly modified by filtration. The deposit collected on the filters consists of fibrinogen, deformed red cells (echniocytes), leucocytes and platelets.

Blood Transfusion↗
PubMed1980

[Determination of the level of plasma beta-thromboglobulin in diabetes].

Plasma beta-TG was measured radioimmunoassay on 23 controls and 84 diabetics. The diabetic patients were divided in three groups: I. Patients without complications, insulin-dependants or not. II. Patients with retinopathy, without severe complications. III. Patients with retinopathy and distal arteritis. beta-TG level in control group is 23,4 +/- 7,6 ng/ml and is comparable with literature. An important increase of beta-TG average level was observed for the three diabetic groups. The almost equal increase between groups I and II could be explained by a comparable hyperagregability, as previously described in diabetes. There could be an increase of hyperagregability with arteritis appearance, and a increase of beta-TG release. Correlation between these two parameters remains to be demonstrated.

Adolescent↗
PubMed1980

[Modifications in hemorheological parameters following acute medical emergencies (author's transl)].

Various hemorheological parameters were studied in venous blood samples taken during the initial stages of acute medical emergencies in patients admitted to the Intensive Care Unit. These included more particularly: cerebrovascular accidents, recent acute arterial or venous thrombosis, pulmonary embolism, acute renal failure, pregnancy toxemia and emergencies occurring during pregnancy or in the puerperium, coagulation disorders, gas embolism... The examinations conducted were:--measurement of apparent--blood viscosity (eta a) and plasma viscosity--platelet aggregate fixation after fixing in formalin according to the method described by Wu and Hoak--blood filterability through filters with pores 5 microns in diameter. The principal modifications observed, often correlated were raised blood and plasma viscosity, reduction in the aggregation index, and diminution in filterability. It should be noted that the increase in viscosity, constant in all groups, is significant at low shearing speeds in the thrombosis cases, and that this significance is present in nearly all the pathological groups with high shearing speeds. Variations in the aggregation index are very dispersed and of low significance.

Blood Viscosity↗
PubMed1979

Analytical study of ionized or ionizable groups of platelet membrane.

The knowledge of the molecular surface groups of the human blood platelets present a particular interest especially in some thrombotic processes or thrombocytopathies. The aim of this study was to approach quantitatively ionized or ionizable groups of the platelet membrane using liquid phase electrophoresis or physicochemical and analytical methods with specific reagents. A mean repartition of the principal groups (carboxyl, SH, amino and phosphate) on the membrane is obtained by cell electrophoresis.

Blood Platelets↗
PubMed1979

Evaluation of a biochemical method for measuring platelet life-span.

Acetylsalicylic Acid (Aspirin) inhibits the formation of Malonaldehyde, a degradation product of the proaggregating Prostaglandins, during the life-span platelets in the circulating blood. After ingestion of 1.5 g of aspirin, there is a blockage of the formation of Malonaldehyde, followed by a progressive return to normal values, after an average of 8 days, in a healthy person. This fact is applied to the determination of half-life, found to be 3.7 +/- 1.3 days; a value in accord with those found by the isotopic method using 51Cr. The reproductibility of this method indicates a clinical application.

Aspirin↗
PubMed1979

[The effect of different plasma substitutes on the viscoelastic properties of blood. Comparison with human albumin].

In a previous study the authors proposed a law of visco-elasticity with three parameters to describe the influence on blood of a forced test according Couette's schedule. The changes produced by different plasma substitutes are studied under equilibrium conditions and under altered conditions. Marked changes were noted in the various parameters. It would appear that these changes are related to the cohesion of erythrocyte rouleaux.

Algorithms↗
PubMed1979

[Compared study of micro-aggregates filters (output, filtration pressure and study of the deposit with scanning electron microscopy) (author's transl)].

Special filters for the elimination of cellular aggregates were conceived especially to prevent pulmonary complications in patients shocked particularly after massive transfusions as well as to prevent cerebral complications after extra-corporeal circulation. The performances and the conditions of use of these filters (perfusion output, change of the filter) were considered. Four filters were carefully studied: the Fenwal filter, the Swank filter, the Biotest filter and the intersep Johnson and Johnson filter. The following studies were carried out for each filter: the perfusion output (of three bottles filtered one after another with or without pressure); the filtration pressure (Swank technique) of the whole blood up-and-down filter; the viscosity and various hematologic parameters (NF, hemoglobin and gobular ATP); finally, the deposit was studied morphologically with scanning electron microscopy. It appeared that a good capacity of aggregates elimination (decrease of the filtration pressure of 95%) was often linked to a feeble output and the necessity of replacing the filter. The efficacy of the Fenwal filter, the Swank filter, the Biotest filter and the intersept filter was practically the same, but the Intersept filter provided the best output with an equal filtration capacity. The other parameters remained about the same. The deposits included fibrinogen, deformed red blood corpuscules (echinocytes), leucocytes and platelets.

Blood Transfusion↗
PubMed1979

Dynamic study of the blood viscosity of insulin-dependent diabetics by means of an artificial pancreas.

The blood viscosity of 15 insulin-dependent, poorly controlled, diabetic subjects was determined by using a microviscosimeter at low shear rates, with cylindrical cuvettes of the Couette type. It was found that the blood viscosity of these diabetics was more elevated than that of control patients (p less than 0.001). In ten diabetics, the return to a strict metabolic control over a period of more than 24 h by means of an artificial pancreas resulted in a significant systematic lowering of blood viscosity. These results suggest that the metabolic control of diabetes influences blood viscosity, and they underline the importance of an artificial pancreas for the dynamic study of the factors affecting blood viscosity during the course of diabetes.

Adolescent↗
PubMed1979

Electrophoretic mobility of Sézary syndrome lymphoid cells.

The variations in electrophoretic mobilities found in different lymphocyte populations present in circulating blood of three patients with Sézary syndrome have been studied. Evidence is given for variations in electrophoretic mobilities being a function of the cytological type of the pathological cells found. The existence of a significant increase of "null" cells is shown, which seem to correspond to Sézary cells.

Electrophoresis↗
PubMed1979

[Variations in blood viscosity of insulin-dependent diabetic subjects controlled by artificial pancreas (author's transl)].

A study of blood viscosity at 3 rates of determination (0.232-0.348 and 1.16 sec-1) in insulin-dependent diabetic subjects controlled by artificial pancreas, shows a reduction in this parameter after 30 hours of feed back control. The relationship between these variations, the mechanical cohesion of the agglutinated red cells, and the deformability of these structures are discussed.

Artificial Organs↗
PubMed1978

Study of amino groups of the human platelet membrane.

The authors attempted to evaluate different reagents in order to quantify the amino groups of the platelet membrane. The study was carried out by the action of different aldehydes and acid anhydrides. The use of 2,4,6-trinitrobenzenesulfonic acid made possible an approach by electrophoresis and chemical assay. The results showed an increase in the surface charge corresponding to a mean number of amino groups varying from 1.86.10(5) groups with citraconic acid to 3.94.10(5) groups with acetaldehyde.

Aldehydes↗
PubMed1978

Physico-chemical interpretation with cells electrophoresis of some antigen -- antibodies reactions in immuno-hematology.

The authors report the action of different antibodies of complete or incomplete type on the electrophoretic mobility of red-blood cells. They try to explain the results in terms of physicochemical stability. They make a distinction between three main possible classes concerning the mechanisms of action: a. direct diminution of the Zeta potential due to the antibody which in this case, is agglutinant. b. diminution of electrocinetic potential by "etching" of ionized groups responsible of the charge. To this mechanism, we could link the increase of the ionic force. c. Artificial increase of the dielectric constant by macromolecules.

ABO Blood-Group System↗