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M F Roudaut

Publications and source records attributed to M F Roudaut.

11 recordsLinked to original sources
PubMed2003

Effect of metformin on fibrinolytic parameters in insulin-treated, type 2 diabetic patients.

OBJECTIVE: In the present study, we measured fibrinolytic parameters, including PAI-1 antigen and activity in a group of type 2 diabetic patients in secondary oral anti-diabetic failure treated with insulin alone or with insulin plus metformin. RESEARCH DESIGN AND METHODS: 12 type 2 diabetic patients in secondary oral anti-diabetic failure were randomly allocated into two groups receiving insulin alone or insulin plus metformin 1000 mg twice a day; six weeks later, the treatments were swapped over. At the end of each treatment period, blood samples were withdrawn for metabolic and fibrinolytic analysis. RESULTS: There were no significant differences in fasting blood glucose, fructosamine or fibrinogen; LDL cholesterol, PAI-1 antigen and activity, insulin needs were reduced by the inulin plus metformin regimen (LDL cholesterol: 1.59 +/- 0.62 versus 1.28 +/- 0.5 mmol/l, PAI-1 antigen: 28.3 +/- 17.4 versus 23.9 +/- 18 ng/ml, PAI-1 activity: 23.8 +/- 9.6 versus 21.9 +/- 10 IU/ml, insulin needs: 64 +/- 18 versus 52 +/- 15 U/day (p<0.05). CONCLUSION: In type 2 diabetic patients with secondary oral treatment failure, insulin alone controlled blood glucose but had no effect on the levels of PAI-1; addition of metformin improved the fibrinolytic parameters.

Aged↗
PubMed2002

[Fibrinolysis and thrombosis of mechanical valvular prosthesis: risk stratification by transesophageal echocardiography].

The place of fibrinolysis in the treatment of mechanical valvular prostheses is still much discussed. The aim of this work is to define the role of transoesophageal echocardiography in risk stratification. This monocentric study draws on 49 cases of thrombolysis preceded by transoesophageal echocardiography (average age 62.1 years, 37 mitral, 11 aortic, 1 tricuspid, 1 mitro-tricuspid). There were 41 obstructive thromboses (OT) and 8 non-obstructive thromboses (NOT). Clinical events and the effectiveness of fibrinolysis were studied as a function of the obstructive or non-obstructive character of the thrombosis and the size of the thrombus < 10 mm (n = 33) or > or = 10 mm (n = 16). Complete success was observed in 34 patients (69.4%). Follow up revealed 2 early cerebral haemorrhages (4.1%) of which one was in the NOT group, and six systemic emboli (12.2%) of which one was in the NOT group. There was a relationship between the size of the thrombus and embolus at the limit of significance in favour of an increased risk of embolus for a voluminous thrombus. Furthermore, the mobility of the thrombi went in hand with an increased rate of systemic emboli (p < 0.01). The rate of failure of fibrinolysis and/or complications correlated with the size of thrombus (complete success in 88% of the < 10 mm thrombus group, versus 35% in the > or = 10 mm; p < 0.01). This work underlines the significance of trans-oesophageal echocardiography in the therapeutic choice for valvular prosthesis thrombosis and suggests that the existence of a voluminous thrombus especially if mobile is a contra-indication for fibrinolysis.

Adult↗
PubMed2001

[Anticoagulation in mechanical valve prostheses. A difficult situation].

Although long-term anticoagulant therapy in patients with mechanical valve prostheses is well codified, a number of difficult situations persists because of the high thromboembolic risk. The protocols of anticoagulation suggested in these situations are controversial as there are no large scale prospective therapeutic trials. However, modern protocols take more and more into account the thromboembolic risk in each individual case. The authors review the most common situations: the early postoperative period for which no precise consensus exists in the literature; anticoagulation in extra-cardiac surgery, a common situation for which the protocols remain very debatable; anticoagulation in pregnancy, a special situation because of the risk of embryopathy with oral anticoagulant therapy and the risk of thromboembolism with heparin; anticoagulation in cases of thromboembolic complications; anticoagulation during infectious endocarditis; anticoagulation during serious haemorrhage.

Anticoagulants↗
PubMed1995

Fibrinolysis and hemorheology in chronic venous insufficiency: a double blind study of troxerutin efficiency.

Abnormal increase of erythrocyte aggregation and reduction of profibrinolytic activity are the two most frequent biological perturbations found in chronic venous insufficiency (CVI). A randomised, controlled, double blind trial was undertaken on 85 patients suffering from grade 1 and 2 CVI, to compare troxerutin with placebo. Two types of biological parameters were measured after 15 days of treatment. Erythrocyte aggregation as evaluated with a Myrenne erythroaggregometer by the indices M (stasis) and M1 (3s-1) progressed favorably in the troxerutin group. The values of M1 at D15 (p < 0.05), and the progression of M (p < 0.001) and M1 (p < 0.01) from D0 to D15, are significantly better in the troxerutin group. Progression of fibrinolytic activity at rest was not significantly different between the 2 groups. Conversely, the progression from D0 to D15 of the values after occlusion of euglobulin lysis time (p < 0.01), tPA (p < 0.01), and PAI activity (p < 0.05) are significantly better in the troxerutin group. The fibrinolysis capacity estimated by euglobulin lysis time (p < 0.01) and tPA (p < 0.05) also progressed favorably in the troxerutin group. These results confirm the anti-erythrocyte aggregation effect of troxerutin, and suggest a favorable effect on blood fibrinolytic activity. They could explain the positive action of this drug on stasis, capillary perfusion and trophic complications of CVL.

Aged↗
PubMed1991

Standard heparin but not LMW heparin induces a concomitant increase of t-PA and PAI-1 without modification of global fibrinolysis: study after 60 days treatment.

The relationship between heparin and fibrinolysis is strongly suggested. We have studied the influence on fibrinolysis of standard heparin (SH), Calciparin and low molecular weight heparin (LMWH), Fraxiparin, given preventively in an elderly population. Patients were randomized into two groups (SH, LMWH). We investigated fibrinolytic parameters (ECLT, t-PA antigen, PAI-1 activity and antigen, t-PA/PAI-1 complexes) before treatment (D0) and at D30 and D60, before and after venous occlusion (VO). Values at D0, D30 and D60 were compared within each group. A significant and marked increase in t-PA and t-PA/PAI-1 complexes at D30 and D60 before and after VO was noted only in the SH group. The mechanism and clinical relevance of this increase remains to be established.

Aged↗
PubMed1987

Thrombolytic treatment of acute thrombotic obstruction with disk valve prostheses: experience with 26 cases.

Twenty-eight episodes of prosthetic valve thrombosis occurred in 26 patients, and all were treated by thrombolytic drugs. The treatment consisted of UK (4500 IU/kg/hr for 12 hours) or SK (2,000,000 IU over 10 hours). The results were followed clinically and in the laboratory and by the same methods that are used for the diagnosis (echocardiography, fluoroscopy) of these problems. Immediate complete regression was seen in 23 cases. These cases did not undergo cardiac surgery. In three cases, in which clear clinical improvement was obtained while both the echocardiography and cinefluoroscopy showed persistent valve dysfunction, the patients were treated medically in two cases (second thrombolysis) and by surgery in one case. In two other cases thrombolysis was ineffective and the patients underwent emergency valve replacement. There were no significant hemorrhagic complications, but emboli from the thrombolysis occurred in five patients. Laboratory data illustrated changes in the success and improvement groups. There were no changes in the failure group.

Adolescent↗
PubMed1986

Soluble fibrinogen derivatives generated by thrombin: affinity for elastin.

When human citrated plasma is dialysed against a phosphate buffer containing Ca++, citrate anions are removed, thrombin is generated and soluble fibrinogen derivatives (fibrin monomers and/or soluble fibrin polymers) are formed. These derivatives are able to combine with human or bovine elastin to form a very stable addition product or adduct. The formation of the adduct is dependent on time, Ca++ and thrombin concentrations.

Animals↗
PubMed1982

[Comparison of platelets frozen with different cryoprotective agents].

A comparative study was performed on platelets frozen with dimethyl-sulfoxide (D.M.S.O.), glycérol and dimethyl-acetamide (D.M.A.C.). The results of tests realized in vitro (platelet yields after thawing platelet aggregation, hypotonic stress, release of enzymes and ultrastructure), and in vivo (life span and recoveries after transfusion) have clearly shown that D.M.S.O. is the best cryoprotective agent. The results obtained with glycerol were less interesting and more clinical data are needed in order to study the hemostatic effectiveness of platelets preserved with this agent. Dimethyl-acetamide gave the worse results and in our opinion, must not be used for the cryopreservation of platelets.

Acetamides↗
PubMedDate not supplied

Multicenter study of an erythro-aggregometer: quality control and standardization.

There is a need for quality assurance procedures in hemorheology, especially for clinical and pharmacological studies, which require reliable and well-calibrated instruments to be interpretable and comparable. Preliminary investigations allowed preparation of standardized SM (normal NS and hyperaggregable HS), and checking of storage conditions (in accordance with the guidelines of the SSC of ISTH) of RBC in nutritive SAG mannitol for at least 2 or 3 weeks with subsequent washings and resuspension in SM. In our study, we compared erythro-aggregometers of the same brand in 6 laboratories, using the same red blood cells (RBC) and suspending media (SM) for each series of tests. EA was measured by laser backscattering with determination of aggregation time (AT), partial dissociation threshold (PDT) and aggregation index (AI). Prior to the study, devices were set up on the same day with the same standardized blood, and calibration data were then analyzed. Within-assay precision (WAP) was assessed on 3 days for the 2 types of SM (n = 18 x 2). Between-assay precision (BAP) was assessed on 6 occasions, once every month (n = 6 x 2 x 6). Accuracy was studied with 3 series of RBC resuspended in 10 SM of "unknown" aggregability. Good agreement was observed between 5/6 centers for the 3 parameters of EA. WEP was good: CV of AT ranging from 1.4 to 2.5% for the NS and from 1.4 to 2.4% for the HS. In each center, BAP was slightly lower than WEP (CV: 8-11.8% for the NS and 3.8-4.7% for the HS over the 6-month study), with no drift, except for one center. Precision was always better with the HS than with the NS which seemed a better tool to assess it. As to accuracy, non-significant differences were generally found between centers, with similar data to the reference values. This work also stressed the importance of the RBC parameter itself in rheological data. For the first time, a protocol for standardization of EA has been developed and evaluated, permitting the Quality Control of this technique.

Analysis of Variance↗