PubMed Health⌕ Search

Biomedical subjects

B Lévy

Publications and source records attributed to B Lévy.

At least 19 recordsLinked to original sources
PubMed2003

[Topical methylprednisolone vs lidocaïne for the prevention of postoperative sore throat].

OBJECTIVE: We assessed the efficacy of topical methylprednisolone or lidocaine for prevention of postoperative sore throat. STUDY DESIGN: Randomised, prospective in single blind study. PATIENTS AND METHODS: Sixty patients ASA 1 or 2 undergoing tracheal intubation for dental surgery received before intubation either topical lidocaine 5% (15 puffs) or aerosolized methylprednisolone (80 mg). Postoperative pain was assessed by the patients using a VAS and a specific scoring system for sore throat, cough and hoarseness. Evaluations were performed immediately after emergence from anaesthesia, 1 h later, at time of the first postoperative drink, at time of the first postoperative meal and 24 h after surgery. RESULTS: Patients receiving methylprednisolone showed slightly better scores for sore throat and cough 1 h after surgery. CONCLUSION: Topical methylprednisolone may therefore be a useful adjuvant in the prevention of sore throat after intubation.

Adult↗
PubMed2003

Cutaneous microvascular effects of mid-term hormone replacement therapy in healthy postmenopausal women: a prospective placebo controlled trial.

OBJECTIVE: To study the mid-term effects of Hormone Replacement Therapy (HRT) on cutaneous microcirculatory blood flow and reactivity in healthy postmenopausal women. DESIGN: In a double-blind placebo controlled randomized study, 16 healthy postmenopausal women received either placebo or HRT (micronized estradiol: 1 mg/day, day 1-28, promegestrone: 0.25 mg/day, day 14-28). This regimen was completed 6 times. Cutaneous microcirculatory blood flow was recorded by laser-Doppler velocimetry on the foot dorsum, in the supine and then dependent positions, and after post-ischemic hyperemia. RESULTS: At day 0, the two groups were similar and none of the following data differed significantly between treated and placebo group: (supine flux: 11.8 +/- 1.8 u vs. 13.2 +/- 3.9, venoarteriolar reflex: 5.6 +/- 1.3 vs. 6 +/- 3.3, and post-ischemic hyperemia: 35.2 +/- 3.9 vs.48.3+/-11). At the end of the study (day 26-28 of 6th cycle), the supine flux was 9.8 +/- 2.1 in the HRT group vs.12.9 +/- 6 in the placebo group (NS), the venoarteriolar reflex, 1.2 +/- 2 vs. 7+/-1.7 (p=0.04), and post ischemic hyperemia, 31.8 +/- 5.4 vs. 39.5 +/- 4.6 (NS). Intragroup values did not change significantly for any of the microcirculatory parameters measured, which remained stable throughout the 6 months of the study. Intergroup values for these parameters did not change either, except for the venoarteriolar reflex, which was lower at the end of the study in the HRT (EP period, cycle 6 day 26-28) than placebo group (p=0.04). CONCLUSIONS: HRT does not impair the resting supine cutaneous microcirculation blood flow or post-ischemic hyperemia.

Double-Blind Method↗
PubMed2001

[Mechanical and functional predictive factors for restenosis and arterial remodeling after experimental angioplasty].

Arterial remodelling plays an important part in post-angioplasty restenosis but the physiopathology of this process is not fully understood. Abundant collagen synthesis and endothelial dysfunction have been demonstrated after angioplasty, but their role in restenosis and remodelling has not been studied. The aim of this study was therefore to assess endothelial function and collagen with respect to the severity of restenosis and the type of arterial remodelling. Atherosclerosis was induced by an association of endothelial abrasion and a high cholesterol diet in the femoral arteries of 22 white New Zealand rabbits. Four weeks later, angioplasty was performed. The acetylcholine endothelium-dependant vasomotricity (expressed as % inhibition of contraction to phenylephrine), collagen and morphology were assessed 28 days after angioplasty. The change in acetylcholine endothelium-dependant vasomotricity was greater in severe restenosis (r = 0.61, p = 0.02). Endothelium-dependant relaxation was not significantly altered when remodelling was expansive and very abnormal when it was constrictive (35.5 +/- 13.0 vs 3.7 +/- 7.9%; p = 0.04). Restenosis was associated with an increase in collagen (r = 0.69, p = 0.004). The density of collagen was significantly higher in constrictive remodelling than in expansive remodelling (34.5 +/- 4.5 vs 18.2 +/- 4.7%; p = 0.03). Endothelial dysfunction and collagen accumulation are correlated with the severity of restenosis and with constrictive remodelling after angioplasty in an experimental model.

Angioplasty↗
PubMed1995

Acute hemodynamic effects of combined inhibition of neutral endopeptidase and angiotensin converting enzyme in spontaneously hypertensive rats.

Neutral endopeptidase inhibitors (NEPI) potentiate the hypotensive effect of converting enzyme inhibitors (CEI) in conscious spontaneously hypertensive rats (SHR) but the mechanism of this potentiation remains unknown. The present study assesses the hemodynamic effects of a CEI (enalaprilat 1 mg/kg; n = 9), a NEPI (retrothiorphan 25 mg/kg + 25 mg/kg/h; n = 9) and the combination (CEI+NEPI; n = 9) versus a control group (n = 9) in anesthetized spontaneously hypertensive rats. CEI alone induced a significant hypotensive effect due to a decrease (-35.1%) in total peripheral resistance (TPR), with no significant increase in cardiac output (CO). NEPI alone had a slight hypotensive effect due to a small decrease in CO. CEI+NEPI decreased the mean arterial pressure to the same extent (-26.7%) as the CEI-induced hypotensive effect, decreased TPR (-44.4%) and induced an increase in CO (+38.2%) with an increase in heart rate. In summary, NEPI combined with CEI induces large decreases in blood pressure and in TPR which do not significantly differ from the CEI-induced effects. It also induces increases in heart rate and in cardiac output in anesthetized SHR.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1993

Spontaneously hypertensive rats and platelet Ca(2+)-ATPases: specific up-regulation of the 97 kDa isoform.

The use of platelets instead of smooth muscle cells (SMC) to study the abnormal Ca2+ handling found in hypertension was investigated using spontaneously hypertensive rats (SHR). We studied the regulation of platelet Ca(2+)-ATPases, as we have recently demonstrated that human platelets, like SMC, contain the Ca(2+)-ATPase isoform termed SERCA2-b (sarco-endoplasmic reticulum Ca(2+)-ATPase). In mixed membranes isolated from platelets of normotensive Wistar-Kyoto (WKY) rats and SHR, total Ca(2+)-ATPase activity was found to be 43% higher in SHR than in WKY rats. By the use of autophosphorylation of rat platelet Ca(2+)-ATPases with [gamma-32P]ATP, followed by SDS/PAGE and Western blotting, we found that rat platelets express two distinct Ca(2+)-ATPases: a 100 kDa isoform, recognized by a SERCA2-b-specific anti-peptide antibody, and a 97 kDa isoform, specifically recognized by a polyclonal anti-SERCA antibody. Comparative analysis of platelet membrane Ca(2+)-ATPases from WKY rats and SHR demonstrated that the expression of the SERCA2-b isoform did not change significantly (128 +/- 22%), whereas that of the 97 kDa isoform reached 300 +/- 35% in SHR when compared with WKY rats. We concluded that the upregulation of total platelet Ca(2+)-ATPases in SHR is not due to the 100 kDa SERCA2-b isoform found in SMC, but is specific to the 97 kDa Ca(2+)-ATPase isoform which is not present in SMC. Therefore platelets should be used with extreme caution as a surrogate model of vascular smooth muscle Ca2+ homeostasis.

Animals↗
PubMed1993

[Malaise in teachers].

A lot is said about present days sense of disarray in teachers. How real is the fact? How come the debate on education is so passionate? Why such shortsightedness in society's vision of its educational system? There truly is happiness in teaching, and this happiness can evolve out of the worst hardships. Nevertheless that happiness is fragile. It is threatened by situational factors and some may be tempted to adopt identity assertive behaviors. Moreover, achieving that happiness might be costly to the individual: situations area often hard on the narcissism, and frequently provoke deceptions proportionate to the moments of complicity shared with the children and adolescents, who reflect passing illusions of what teachers themselves were.

Adaptation, Psychological↗
PubMed1992

[Continuous venovenous hemofiltration after cardiac surgery. A retrospective study in 16 patients with multiple organ failure].

As intermittent haemodialysis in critically ill patients is often associated with circulatory instability and hypotension, pumped continuous veno-venous haemofiltration (CVVH) has been proposed as an alternative. This technique was used postoperatively in 16 cardiac surgery patients with cardiogenic shock (cardiac index < 2.2 l.min-1.m-2), anuria and multiple organ failure. A mean haemofiltration rate of 0.5 to 1 l.h-1 was used. Average length of treatment was 57 +/- 38 h. Two patients were improved and weaned from CVVH after 96 and 144 h respectively. The other fourteen died. A mean 200 +/- 50 ml of liquid were removed every hour. The technique was well tolerated by the cardiovascular system. The systolic arterial pressure, heart rate and cardiac index remained unchanged. Body weight had decreased by 3 +/- 1 kg after 48 h of use. Similarly, serum creatinine concentration was lowered from 337 +/- 32 mmol.l-1 to 252 +/- 27 mmol.l-1 (p < 0.001). At that time, urea and creatinine clearances were 18 +/- 2 ml.min-1, and 15 +/- 1 ml.min-1 respectively. After 24 h of CVVH, both serum sodium and potassium concentrations had been decreased, from 148 +/- 3 mmol.l-1 to 142 +/- 2 mmol.l-1 (p < 0.001), and from 5.7 +/- 0.3 to 4.2 +/- 0.15 mmol.l-1 (p < 0.001) respectively. In addition, pH increased significantly from 7.13 +/- 0.1 to 7.30 +/- 0.04 (p < 0.001). These results were comparable with these of other authors regarding safety and efficiency of CVVH. The low patient survival rate (12.5%) was due to the severity of cardiac impairment.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗
PubMed1990

Non-mammalian "big" neurophysins--complete amino acid sequence of a two-domain MSEL-neurophysin from goose.

Vasotocin-associated neurophysin (MSEL-neurophysin) has been purified from goose neurohypophysis through molecular sieving and high-pressure reverse-phase liquid chromatography (HPLC). The protein has a molecular mass (measured by SDS-polyacrylamide gel electrophoresis) of 17 kDa in contrast to 10 kDa found for the mammalian MSEL-neurophysins. Complete amino acid sequence (131 residues) has been determined mainly through tryptic or staphylococcal proteinase peptides derived from carboxyamidomethylated neurophysin, isolated by HPLC and microsequenced. N- and C-terminal sequences have been established by Edman degradation or action of carboxypeptidase Y, respectively, applied on the native protein. Goose MSEL-neurophysin is homologous to the two-domain "big" MSEL-neurophysin previously identified in the frog. It appears that in non-mammalian tetrapods, namely birds and amphibians, the proteolytic processing of the pro-vasotocin involves only one cleavage, releasing the hormone moiety and a "big" neurophysin with two domains homologous to mammalian MSEL-neurophysin and copeptin, respectively. Comparison of the avian protein with its mammalian and amphibian counterparts reveals that the first half of the polypeptide chain is evolutionarily much less variable than the second and that the goose protein resembles the frog protein much more than the mammalian one.

Amino Acid Sequence↗
PubMed1990

Complete amino acid sequence of goose VLDV-neurophysin. Traces of a putative gene conversion between promesotocin and provasotocin genes.

Goose VLDV-neurophysin (mesotocin-associated neurophysin) has been purified from posterior pituitary glands through molecular sieving on Sephadex G-75 and high-pressure reverse-phase liquid chromatography on Nucleosil C-18 columns. Despite apparent molecular mass of unreduced VLDV-neurophysin measured by polyacrylamide gel electrophoresis with sodium dodecylsulfate appeared near 17 kDa, this value fell to 11 kDa after reduction with mercaptoethanol, suggesting the existence of a homodimer. Complete amino acid sequence (93 residues) of goose VLDV-neurophysin has been determined. N- and C-terminal sequences of the protein have been established by Edman degradation (microsequencing) and use of carboxypeptidase Y, respectively. Peptides derived from oxidized or carboxamidomethylated neurophysin by trypsin or staphylococcal proteinase hydrolyses have been isolated by high-pressure liquid chromatography and microsequenced, allowing determination of the complete sequence. Comparison within the vertebrate VLDV-neurophysin lineage, namely goose VLDV-neurophysin to mammalian VLDV-neurophysins and to deduced toad VLDV-neurophysin, reveals a residue insertion between positions 66 and 67 in the nonmammalian VLDV-neurophysins. When goose MSEL-neurophysin (vasotocin-associated neurophysin) and goose VLDV-neurophysin are compared to their bovine counterparts, identical substitutions are found in positions 17 (Asn in both goose neurophysins instead of Gly in both ox neurophysins), 18 (Arg instead of Lys), 35 (Tyr instead of Phe), and 41 (Thr instead of Ala). Identity of the sequences 10-74 in both ox neurophysins has been explained by partial gene conversion between oxytocin and vasopressin genes, and identical substitutions in both goose neurophysins might reveal a similar gene conversion between mesotocin and vasopressin genes in birds.

Alkylation↗
PubMed1990

[Non-invasive study of hemodynamics in peripheral arteries by pulsed Doppler associated with bidimensional echography. A preliminary study].

The purpose of this study is the validation of a 2D-echography and range-gated system to measure internal diameter, and instantaneous blood flow velocity, and to calculate the blood flow, in peripheral arteries (i.e. common carotid artery, femoral artery, and humeral artery). The artery is first visualized using the echographic array probe, its internal diameter (D) is determined and its cross sectional area (S) calculated; the array of the ultrasonic system and the doppler probe are attached and forme a fixed angle. The range-gated doppler system allows the measurement of instantaneous blood flow velocity, with a position of the sample volume covering the internal diameter. Instantaneous velocities are integrated on several cardiac cycles to calculate the mean velocity (Vm). (S. Vm) measures the blood flow. The echographic array probe allows a control of the doppler beam position. In vitro velocities have been measured (N = 20). The fixed angle is 38 degrees 30'; there is an obvious relationship between the calculated and the measured velocities (r = 0.982; p less than 0.0001). The intra-observer reproducibility of measures on common carotid arteries (CCA), femoral arteries (FA), and humeral arteries (HA). In 7 normal patients is, respectively: diameters: (4.9%, 4.12%, 10.2%); velocities: (8.9%, 10.6%, 10.2%). The inter-observers reproducibility is respectively: diameters: (5.6%, 5.4%, 11.4%); velocities: (6.5%, 5.7%, 6.3%). The comparison of 11 measures of diameters and velocities with 20 range-gated doppler gives an obvious relationship (respectively, r = 0.99 p less than 0.0001, r = 0.996, p less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Isolation of neurosecretory granules containing vasotocin, mesotocin, MSEL- and VLDV-neurophysins from goose neurohypophysis.

Neurosecretory granules have been isolated from goose posterior pituitaries and their contents have been analyzed by reverse-phase high-pressure liquid chromatography and polyacrylamide gel electrophoresis. Vasotocin and mesotocin have been identified by their biological activities and their retention times compared with those of synthetic peptides. MSEL- and VLDV-neurophysins have been characterized by their N-terminal sequences, their electrophoretic migrations and their retention times, compared with those of purified goose neurophysins. In contrast to the two-step processing of mammalian provasopressin, processing of the vasotocin - MSEL-neurophysin precursor appears to involve only one cleavage giving the hormone and a "big" MSEL-neurophysin homologous to mammalian MSEL-neurophysin extended by copeptin.

Animals↗
PubMed1989

[Function and structure of the vascular wall in experimental arterial hypertension. Effect of treatment].

The effects of converting enzyme inhibitor have been studied on the functions and structure of the arterial wall, and in both models of renovascular and spontaneously hypertensive rats. The arterial wall functions have been studied in terms of active vasomotricity, passive elasticity and transparietal convexion transport of proteins. Whatever the model used, hypertension was associated with significant changes in arterial wall functions: increase in smooth muscle cell tone, decrease in compliance, and decrease in transparietal filtration rate of proteins. These modifications could be reported to the increase in thickness of the media secondary to hypertrophy and hyperplasia of smooth muscle cell and to the increase in collagen network density. The effects of converting enzyme inhibitors on these phenomenons could depend on the experimental model used and the duration of treatment. In renovascular hypertensive animals, one month of treatment with perindopril normalized blood pressure and active compliance of the arterial wall. This functional benefit could be easily reported to the complete regression of the smooth muscle cell hypertrophy observed after treatment. By contrast, the increase in collagen network density was not regressed by treatment. By contrast, the increase in collagen network density was not regressed by treatment. By contrast, the increase in collagen network density was not regressed by treatment with trandolapril and thus the transparietal filtration rate of proteins remained decreased. In spontaneously hypertensive rats a perindopril treatment of long duration (3 months) partially regressed the functional change in compliance. This effect, once again, could be easily reported to the partial regression of medial hypertrophy which was associated, in this experimental condition, with a significant decrease in collagen network density.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1988

[Non-invasive measurement by Doppler pulse of cardiac output and maximal aortic acceleration in essential arterial hypertension].

Three groups of 11 male subjects with the same mean age were studied: normotensives (group I), patients with sustained essential hypertension (group II) and patients with borderline hypertension (group III). M-mode echocardiography provided a measure of aortic root systolic diameter (D) and left ventricular mass index (LVMi, g/m2). We have used a 4 MHz pulsed doppler velocity meter with spectral analysis to measure instantaneous ascending aortic blood velocity. Measurements values were averaged during 10 s and included: stroke volume (SV, cm3 = integrated velocity over one cardiac cycle.aortic cross sectional area (3.14D2/4)), cardiac output (CO, cm3 = SV.heart rate), systemic vascular resistance (SVR, mmHg/cm3.s-1 = MAP/co) and maximal aortic acceleration (MA, cm/s2). (Table: see text). Stroke volume and cardiac output were similar in three groups. SVR was higher in group II than in group I. The myocardial contractility appreciated from the maximal aortic acceleration (Bennett et al, Cardiovasc Res 1984; 18: 632-8) was increased in patients with borderline hypertension and remained within the normal range in patients with sustained essential hypertension despite and increase in cardiac mass.

Adult↗