Biomedical subjects

E Lesaffre

Publications and source records attributed to E Lesaffre.

At least 73 records · Page 4Linked to original sources

PubMed1995

Epidemiological data of patients treated with fluvoxamine: results from a 12 week non-comparative multicentre study.

In an open multicentre study designed to closely reflect the clinical situation, 315 out-patients diagnosed by their psychiatrist as having depression and/or obsessive-compulsive disorder (OCD), and/or panic disorder, were treated for 12 weeks with fluvoxamine (100-300 mg/day). Twelve weeks of fluvoxamine therapy was completed by 229 (73%) patients. Longer illness duration prior to treatment was associated with a significantly reduced rate of treatment withdrawal, whereas a diagnosis of OCD was predictive of treatment withdrawal. The main reasons patients discontinued fluvoxamine therapy were adverse effects experienced before Week 8, and clinical improvement thereafter. Age, sex, and diagnosis had no predictive value for treatment outcome; however, psychiatric antecedents and duration and severity of illness at baseline were significant predictors of disease severity at endpoint. Fluvoxamine decreased both the frequency and severity of baseline symptoms, with improvement continuing for the duration of the study. Nausea was the only symptom to show an initial increase in frequency and severity, but this subsided after 4 weeks to levels below baseline frequency and severity.

Adult↗

PubMed1994

An evaluation of a light-curing composite for bracket placement.

In this study the clinical usefulness of a light-curing (Heliosit) and a chemically-curing composite (Concise) for orthodontic bracket bonding were compared. A sample of 37 patients to be treated with full Edgewise (FE) appliance in one or both arches (in total 52 dental arches) were randomly selected to have brackets on the left or right side of the dental arch bonded either with Concise or with Heliosit. In 12 patients, two teeth were extracted before orthodontic treatment and 25 patients were treated non-extraction. Impressions (Impregum) of the tooth surface and the bracket were made immediately after bracket loss. Frequency scores of bracket loss were noted for both composites and scanning microscopic evaluation of the tooth/composite surface was performed. Significant differences in bracket loss could be demonstrated between the two composites as a whole, and between the anterior and posterior parts of the dentition. For Heliosit bracket loss was observed predominantly in the posterior region, while for Concise it was distributed more equally over the dental arches. It was, however, demonstrated that in the clinical situation of bracket bonding the chemically-cured Concise failed significantly less than Heliosit in the overall frequency score.

Bicuspid↗

PubMed1994

Early and late exercise capacity after acute myocardial infarction treated with recombinant tissue-plasminogen activator.

Thrombolytic therapy salvages jeopardized myocardium and preserves left ventricular function. Therefore, a beneficial effect on exercise tolerance and haemodynamic adaptation to exercise can be anticipated. In the present study the results of bicycle exercise tests, performed at 10 to 14 days and at more than 1 year after infarction, were compared between patients randomized double blindly to recombinant tissue plasminogen activator (rt-PA) or placebo. At 2 weeks, the maximal heart rate (140 vs 130 beats.min-1 P = 0.017), systolic blood pressure (169 vs 161 mmHg, P = 0.018) and pressure-rate product (22907 vs 20865 beats.min-1.mmHg, P = 0.0025) were higher in rt-PA treated patients (n = 145) than in controls (n = 142). At a mean follow-up of 16 months, rt-PA patients (n = 126) performed a higher total and peak work load (733 vs 600 Watts.min, P = 0.027 and 133 vs 100 Watts, P = -0.036, respectively) than control patients (n = 122). During both exercise tests the incidence of clinical or electrocardiographic signs of ischaemia was similar. Multiple regression analysis indicated that age and end-systolic volume were predictors of peak pressure-rate product at 2 weeks (R2 = 0.11, P = 0.0001). Age, sex and left ventricular ejection fraction at discharge were independent predictors of peak work load at 2 weeks (R2 = 0.32, P = 0.0001) and the square root of peak work load at 16 months (R2 = 0.39, P = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Double-Blind Method↗

PubMed1994

At equipotent doses, isradipine is better tolerated than amlodipine in patients with mild-to-moderate hypertension: a double-blind, randomized, parallel-group study.

1. The objective of this double-blind parallel-group study was to compare the tolerability of isradipine and amlodipine, specifically, the side-effects known to be related to the use of dihydropyridine calcium antagonists. 2. A total of 205 patients with mild-to-moderate essential hypertension were randomized to receive either the sustained-release (SRO) formulation of isradipine (n = 103) or amlodipine (n = 102), both at dosages of 5 mg once daily. Blood pressure measurements were taken at the end of the dosing interval to assess the antihypertensive efficacy of the two drugs. 3. Adverse reactions were assessed in two ways: a) spontaneously reported adverse events were recorded and investigated in depth for severity, duration, relation to the study drug, and outcome; b) a questionnaire was used to elicit specific adverse reactions known to be related to the use of dihydropyridine calcium antagonists which were evaluated for severity, duration, relation to the study drug, and outcome. 4. After 6 weeks of active treatment, both isradipine and amlodipine reduced mean sitting systolic/diastolic blood pressure: from 165.1/100.1 to 145.2/89.7 mm Hg with isradipine; and from 164.1/100.6 to 145.7/90.5 mm Hg with amlodipine. There was no difference in antihypertensive effect between isradipine and amlodipine (95% CI: -3.73 to 4.73 and -1.89 to 3.49 for differences in systolic and diastolic blood pressure, respectively). 5. The number of patients spontaneously reporting adverse events was significantly higher (P = 0.02; 95% CI: 3.1 to 26.7%) with amlodipine (33.3%) than with isradipine (18.4%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

Suppression of gonadotropin secretion in the hospitalized postmenopausal female as an effect of acute critical illness.

Plasma gonadotropins were measured in 126 postmenopausal women (age range 69-90 years) admitted to a geriatric ward. After clinical examination, patients were classified as 'acutely or severely ill' or as 'not ill'. Plasma gonadotropins were compared between both groups. Logistic regression was used to select clinical and/or biochemical parameters which differentiated patients with abnormal, low gonadotropins from patients with high gonadotropin concentrations. Plasma gonadotropins were significantly lower in the 'acutely or severely ill' than in the 'healthy' patient group. By logistic regression, blood sedimentation rate, total protein concentration, and serum thyrotropin concentration were significantly correlated with low gonadotropins. Linear regression analysis showed a significant linear relationship between plasma gonadotropins and age (at least for ages over 80 years), blood sedimentation rate (at values more than 65 mm) and total protein concentration. Marked suppression of plasma gonadotropins was frequently found to occur in acutely ill postmenopausal women, in relation to biochemical parameters of acute illness such as blood sedimentation rate, total protein concentration, and serum thyrotropin. In addition, ageing per se seems characterized by a progressive attenuation of the high postmenopausal gonadotropin levels.

Acute Disease↗

PubMed1994

An application of maximum likelihood and generalized estimating equations to the analysis of ordinal data from a longitudinal study with cases missing at random.

Data are analysed from a longitudinal psychiatric study in which there are no dropouts that do not occur completely at random. A marginal proportional odds model is fitted that relates the response (severity of side effects) to various covariates. Two methods of estimation are used: generalized estimating equations (GEE) and maximum likelihood (ML). Both the complete set of data and the data from only those subjects completing the study are analysed. For the completers-only data, the GEE and ML analyses produce very similar results. These results differ considerably from those obtained from the analyses of the full data set. There are also marked differences between the results obtained from the GEE and ML analysis of the full data set. The occurrence of such differences is consistent with the presence of a non-completely-random dropout process and it can be concluded in this example that both the analyses of the completers only and the GEE analysis of the full data set produce misleading conclusions about the relationships between the response and covariates.

Age Factors↗

PubMed1994

The Monostrut versus Medtronic Hall prosthesis: a prospective randomized study.

A prospective randomized study, comparing the clinical results between two groups of patients undergoing valve replacement with the Monostrut (MS) and Medtronic-Hall (MH) heart valve prosthesis was carried out between January 1985 and December 1988. A MS valve was implanted in 205, the MH in 198 patients selected randomly. Statistical analysis showed a perfect match between the two groups regarding preoperative and operative variables, including implantation site. All patients were given life-long anticoagulant therapy after operation. Follow up was 5.06 years (median) with a total of 1971.1 patient-years (pty) and 96.6% complete. The two groups showed no significant difference in the incidence of the following postoperative events: 30-day mortality, late mortality, reoperation, anticoagulant related bleeding, paravalvular leak, prosthetic valve endocarditis and thromboembolism (TE). Multivariate analysis indicated a borderline increased hazard of TE (2.1 +/- 0.4%/pty versus 0.7 +/- 0.2%/pty) (p = 0.0087, Bonferoni corrected significance) in the MS group. It is concluded that long term outcome is excellent with these two tilting disc valves. The marginally lower incidence of thromboembolism, however, favors the Medtronic Hall prosthesis.

Adolescent↗

PubMed1994

Prediction of event-free survival after hospital discharge in acute myocardial infarction treated with tissue-plasminogen activator.

The incidence of recurrent ischemia, congestive heart failure and death during the first year after discharge were analysed prospectively in a group of 312 patients randomized double blindly to rt-PA (n = 156) or placebo within 5 hours after the onset of acute myocardial infarction. The in-hospital mortality was 4.4% in the rt-PA and 6.4% in the placebo group; the total-mortality after a follow-up of 16 months was respectively 7.6 and 9.6%. During 16 months follow-up reinfarction occurred in 5.4% of the rt-PA treated patients versus 0.0% in controls (p = 0.004). Revascularization was required in 17% of the population (24% in rt-PA versus 16% in controls, N.S.), angina at rest and congestive heart failure, demanding hospitalization developed in 5.1% of the patients (5.3% in rt-PA versus 4.7% in controls, N.S.) and 3.4% of the patients in each group died after discharge. A logistic model constructed to predict event-free survival showed that enzymatic infarct size, exercise capacity and the hemodynamic response at a predischarge bicycle exercise test and end-systolic volume at 2 weeks were predictors of new events. Considerable overlapping between patients with and without a new event was observed.

Double-Blind Method↗

PubMed1994

The Inter-regional Belgian Bank Employee Nutrition Study (IBBENS).

OBJECTIVE: This study compares the dietary intake in different geographical areas in Belgium. DESIGN: Food habits were examined by the 3-day food record with additional intervieW. SETTING: The study was performed in the head offices of one bank situated in seven Dutch-speaking cities (spread over two districts) in the north and one French-speaking city in the south of Belgium. SUBJECTS: 371 male and 192 female healthy employees participated in the survey. RESULTS: The results show a difference in fat consumption between north and south. Men in the French-speaking district consumed on average 18.8 E% (SD = 3.2) of saturated fat, compared to 16.2 (2.8) and 16.7 (2.9) E% for the two Dutch-speaking districts (P < 0.001). For women the respective data are 18.9 (3.2), 16.4 (3.0) and 17.1 (3.1) E% (P < 0.01). The E% of polyunsaturated fat in the three districts equals respectively 5.2 (1.8), 7.2 (2.4) and 6.7 (2.5) (P < 0.001) for men; 4.9 (1.8), 7.2 (2.7) and 6.6 (2.2) (P < 0.001) for women. A significantly lower P/S ratio (P < 0.001, for both sexes) and U/S ratio (P < 0.001, for both sexes) was found in the south. The intake of cholesterol (mg per 4.18 MJ) was significantly higher in the south (P = 0.01, for both sexes). The differences between the Dutch-speaking centres were relatively small. For men significant differences in P/S ratio, 0.48 (0.22) in the east versus 0.43 (0.20) in the west (P < 0.001), and in E% of monounsaturated fat, 15.2 (2.7) versus 16.3 (3.1) (P < 0.01), could be established. CONCLUSION: Differences in fat intake exist between the north and the south of Belgium. Within the north significant differences exist in P/S ratio and in intake of monounsaturated fat.

Adult↗

PubMed1993

Calculation of power and sample size with bounded outcome scores.

The two-sample Wilcoxon rank sum test is the most popular non-parametric test for the comparison of two samples when the underlying distributions are not normal. Although the underlying distributions need not be known in detail to calculate the null distribution of the test statistic, parametric assumptions are often made to determine the power of the test or the sample size. We encountered difficulties with this approach in the planning of a recent clinical trial in stroke patients. It is shown that, for power and sample size estimation, it can be dangerous to apply the classical formulae routinely, especially with outcome scores having a U-shaped or a J-shaped distribution. As an example we have taken the Barthel index, a quality-of-life outcome measure in stroke patients. Further, we have investigated alternative methods by means of Monte Carlo simulation. The distributional characteristics of the estimated powers were compared. Our findings suggest more appropriate computer software is necessary for the calculation of power and sample size when efficacy is measured by a non-parametric method.

Cerebrovascular Disorders↗

PubMed1993

A new quantitative method for the analysis of cardiac perfusion tomography (SPET): validation in post-infarct patients treated with thrombolytic therapy.

In this study a new method for assessment of perfusion defects (PDs) derived from myocardial perfusion tomograms was evaluated in patients treated with thrombolytic therapy. Using global constraints and dynamic programming, a model-based delineation algorithm defined myocardial borders, the basal plane and absolute and relative PD size in 49 thallium-201 chloride (201TL CL) and 60 technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) tomograms. Tomographic (single-photon emission tomography: SPET) and planar quantification of PDs was compared to enzymatic infarct size as well as to global (LVEF) and regional ventricular function (RWM) obtained by contrast angiography. The algorithm delineated the myocardium and the valve plane in most cases, even when large PDs were present. Manual correction of the automatic delineation of the basal plane was necessary in less than 20% of the studies. Using 201Tl Cl, LVEF correlated better with tomographic PD (r = -0.67) than with planar PD (r = -0.54). Comparing planar to tomographic imaging using 99mTc-MIBI, a higher correlation with enzymatic infarct size (r = 0.73 vs 0.57) and with global ventricular function (r = 0.64 vs -0.52) was found when tomographic techniques were used. No close correlation between PD and RWM was found. The beneficial effect of thrombolysis was shown by a significant difference of PD in patients with open versus occluded infarct-related vessels. It can be concluded that this new automated algorithm for quantification of SPET perfusion defect size provides a useful tool in evaluating thrombolytic therapy.

Algorithms↗

PubMed1993

Three-year follow-up of five posterior composites: SEM study of differential wear.

Assessing the wear of both enamel and composite at a shared occlusal contact area offers the opportunity to determine the differential wear between enamel and composite on the same tooth. Differential wear measurements were carried out on five posterior composite materials with an accurate 3D-measuring technique. The distinct wear step between enamel and composite was visualized by means of scanning electron photomicrographs. Both investigated ultrafine midway-filled and fine compact-filled composites (Willems et al., 1992a) have a considerably higher differential wear value and are, therefore, less suitable for rehabilitation of posterior teeth than are the ultrafine compact-filled composites, which have, in this study, a very satisfactory differential wear rate and appear to be highly wear resistant materials suitable for use in stress-bearing areas.

Adult↗

PubMed1993

Short-term effects of early intravenous treatment with a beta-adrenergic blocking agent or a specific bradycardiac agent in patients with acute myocardial infarction receiving thrombolytic therapy.

OBJECTIVES: This study was conducted to explore mechanisms that could explain the possible clinical benefit of early administration of a beta 1-selective adrenoreceptor blocking agent or a bradycardiac drug as adjunct to thrombolysis in acute myocardial infarction. BACKGROUND: The effects of beta-blockers given concomitantly with thrombolytic therapy in patients with acute myocardial infarction have not been fully examined. The potential role of specific bradycardiac agents lacking negative inotropism as an alternative to beta-blockers in this setting has never been studied in humans. METHODS: In a double-blind study, we examined the effects of early intravenous and continued oral administration of a beta-blocker (atenolol), a specific bradycardiac agent (alinidine) or placebo on left ventricular function, late coronary artery patency, infarct size, exercise capacity and incidence of arrhythmias. RESULTS: A total of 292 patients with acute myocardial infarction of < or = 5 h duration and without contraindications to thrombolytic or beta-blocker therapy were studied. Of these, 100 were allocated to treatment with atenolol (5 to 10 mg intravenously followed by 25 to 50 mg orally every 12 h), 98 to alinidine (20 to 40 mg intravenously followed by 20 to 40 mg orally every 8 h) and 94 to placebo. All patients received 100 mg of alteplase over 3 h and full intravenous heparinization. No significant differences in coronary artery patency, global ejection fraction or regional wall motion were observed at 10 to 14 days among the three groups. Likewise, enzymatic and scintigraphic infarct size were also very similar. Neither atenolol nor alinidine was associated with a significant reduction in the incidence of arrhythmias during the 1st 24 h. No significant differences in clinical events were observed, with the exception of a greater incidence of nonfatal pulmonary edema in the atenolol group (6% vs. 1% in the alinidine group and 0% in the placebo group, p = 0.021). CONCLUSIONS: In the absence of contraindications, the administration of a beta-blocker or a specific bradycardiac agent together with thrombolytic therapy was safe. In this limited number of patients, these agents did not appear to enhance myocardial salvage or preservation of left ventricular function or to reduce the incidence of major arrhythmias in the early phase of infarction.

Adult↗

PubMed1993

Serum erythropoietin levels in elderly inpatients with anemia of chronic disorders and iron deficiency anemia.

OBJECTIVE: To analyze the relationship between serum erythropoietin levels and hemoglobin levels in elderly patients with anemia of chronic disorders related to cancer or acute infection when compared with anemic patients with iron deficiency. DESIGN: Prospective survey with comparison groups. SETTING: Tertiary care center. PATIENTS: An elderly group aged 70 and above (mean 84, range 70-96) was divided into subgroups of 45 with anemia of chronic disorders (23 with cancer and 22 with acute infection), 24 with iron-deficiency anemia, and 27 with no anemia. Thirty non-anemic younger adults were also studied. MEASUREMENTS: Serum erythropoietin (radioimmunoassay), complete blood count, serum iron, B12, folate and ferritin, liver and kidney function tests, blood gas analyses, and bacteriological and radiological tests. RESULTS: The serum erythropoietin levels were significantly lower in the elderly non-anemic hospitalized group than in the healthy younger group. A significant negative relationship between the log serum erythropoietin and hemoglobin levels was found in patients with iron deficiency, but not in the other groups. For any given hemoglobin level, the response of erythropoietin was significantly higher in anemic patients with iron deficiency when compared with the neoplastic and infectious group. CONCLUSION: Erythropoietin response to anemia is blunted in elderly patients with anemia of chronic disorders related to cancer or acute infection. Erythropoietin level is lower in non-anemic elderly inpatients than in healthy younger persons.

Acute Disease↗

PubMed1993

Cobalamin absorption and serum homocysteine and methylmalonic acid in elderly subjects with low serum cobalamin.

We prospectively studied 41 consecutive elderly patients with serum cobalamin (vitamin B12) levels lower than 125 pmol/l. The protein-bound cobalamin absorption test (PBAT) was performed in 34 of them and in 27 selected elderly control patients. The lower decision limit was 0.18% and an abnormal test was detected in only 9 (26%) of the 34 patients with low serum cobalamin level. When the PBAT was compared to the Schilling (Dicopac method) test, a concordant result was found in 80%. Serum methylmalonic acid and/or total homocysteine concentrations were elevated in 75% (26/35) of the patients with low serum cobalamin levels but also in 30% (5/17) of the control patients. Of the 12 and 9 cobalamin-deficient patients with elevated serum levels of methylmalonic acid and homocysteine, normalization after cobalamin therapy was obtained in 11 and 5 respectively. In conclusion, determination of serum metabolites and their response to cobalamin therapy are a sensitive index of significant cobalamin deficiency and a useful means of distinguishing between cobalamin and folate deficiency. The PBAT offers little advantage over the Schilling test in diagnosing cobalamin malabsorption in elderly patients.

Aged↗

PubMed1993

The Björk-Shiley Monostrut valve. Clinical experience in 647 patients.

A total of 647 consecutive patients underwent valve replacement with a Björk-Shiley Monostrut valve (Shiley, Inc., Irvine, Calif.) from January 1, 1984, through December 31, 1988. A total of 135 patients (20.8%) had had a previous cardiac correction. Overall hospital mortality was 6.8%. Preoperative functional class, cardiopulmonary bypass time, aortic crossclamping time, and cause of valve replacement influenced in-hospital mortality significantly (univariate analysis). The median follow-up was 30 months. Overall actuarial survival was 81% +/- 4% at 6 years. Univariate and multivariate regression analysis showed that preoperative functional class, total cardiopulmonary bypass time, size of mitral prosthesis, and pure mitral insufficiency significantly influenced total mortality after valve replacement. Additional coronary bypass grafting and redo valve replacement did not. The actuarial rate of freedom from thromboembolism was 86% +/- 4% at 6 years. There were no cases of valve thrombosis. Patients having a thromboembolic event showed a higher probability of late death after native valve replacement.

Actuarial Analysis↗

PubMed1993

Early and late effects of rt-PA vs placebo on left ventricular function measured by nuclear ventriculography.

The aim of the study was the functional re-evaluation of 296 patients 12 to 18 months after a double-blind trial evaluating the effect of tissue plasminogen activator (rt-PA) versus placebo given within 5 h of onset of symptoms caused by an acute myocardial infarction. All patients underwent rest-stress radionuclide angiography (Egna). For each exercise level the global left ventricular ejection fraction (LVEF) was calculated together with an estimate of regional wall motion abnormalities (RWMA). A clear difference of the total workload and the peak workload was found between both therapeutic groups. Discriminant analysis evaluating four parameters (LVEF at peak exercise and at the endpoint and the workload at those levels) revealed a beneficial therapeutic effect. The RWM at rest showed only a difference in the apico-inferior region. There were less wall motion abnormalities in the treated group. Radionuclide analysis demonstrated a larger functional capacity and a better coordination of myocardial contractility during stress RNA one year after thrombolytic therapy. At rest, no major differences were found between the hospital stage and the follow-up in both therapeutic groups one year later.

Adult↗

PubMed1992

Synergistic antithrombotic properties of G4120, a RGD-containing synthetic peptide, and argatroban, a synthetic thrombin inhibitor, in a hamster femoral vein platelet-rich thrombosis model.

The synergistic antithrombotic properties of G4120, a synthetic Arg-Gly-Asp (RGD) containing peptide which strongly inhibits platelet aggregation, and of Argatroban, a synthetic thrombin inhibitor, were examined in a reproducible quantitative hamster femoral vein platelet-rich mural thrombosis model. Bolus injections of G4120 and Argatroban inhibit thrombus formation in a dose-dependent way; 50% inhibition (ID50) is obtained with 11 micrograms/kg G4120 and with 2 mg/kg Argatroban. Combined bolus injections of 3 micrograms/kg G4120 with 0.5, 0.75 or 1 mg/kg Argatroban and of 1 mg/kg Argatroban with 1.5 or 3 micrograms/kg G4120 caused linear dose-dependent inhibition of thrombus formation, whereas 3 micrograms/kg G4120 or 1 mg/kg Argatroban alone had very little effect (less than 20% inhibition). ID50 was obtained with the combination of 3 micrograms/kg G4120 and 0.5 mg/kg Argatroban, corresponding to an equi-effective fractional combination of 0.62 with a 95% confidence interval of 0.50 to 0.74. Alternatively the ID50 was obtained with the combination of 1 mg/kg Argatroban and 1.3 micrograms/kg G4120, corresponding to an equi-effective fractional combination of 0.52 with a 95% confidence interval of 0.18 to 0.86. In both instances these results are indicative of a significant synergistic interaction. Bolus injection of 10 mg/kg aspirin, 100 U/kg heparin or the combination did not inhibit thrombus formation. The synergistic effect of the combination of platelet inhibiting RGD-peptides and synthetic thrombin inhibitors could be useful in the prevention of arterial occlusion with platelet-rich thrombus in patients with ischemic heart disease following thrombolytic therapy or angioplasty, although this combination is not expected to reverse platelet thrombus formation.

Animals↗