PubMed Health⌕ Search

Biomedical subjects

P Geslin

Publications and source records attributed to P Geslin.

At least 37 records · Page 2Linked to original sources
PubMed1999

In-vitro bacteriostatic activity of levofloxacin and three other fluoroquinolones against penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae.

The purpose of this study was to investigate the in-vitro bacteriostatic activity of levofloxacin in comparison with that of ofloxacin, sparfloxacin and ciprofloxacin against 205 strains of Streptococcus pneumoniae (101 penicillin-susceptible, 51 penicillin-intermediate and 53 penicillin-resistant). The isolates were provided between September 1996 and October 1996 by French hospitals participating in the National Co-operative Survey of Pneumococcal Infections. The determination of MICs (mg/L) was made by the agar dilution method. The MIC50 and MIC90 values of the four fluoroquinolones for the three classes of S. pneumoniae (penicillin-susceptible, penicillin-intermediate and penicillin-resistant) were not significantly different. In contrast, the differences in in-vitro activity observed among the four fluoroquinolones against the 205 strains allowed them to be separated into three groups: sparfloxacin (MIC50/90 0.25 mg/L); ciprofloxacin and levofloxacin (MIC50 0.5 and 1 mg/L respectively, MIC90 1 mg/L); and ofloxacin (MIC50 1 mg/L, MIC90 2 mg/L). A total of 204 of the strains had a levofloxacin MIC between 0.25 mg/L and 1 mg/L, and only one of the 205 strains was highly resistant (MIC 16 mg/L). Whatever the level of susceptibility to penicillin, the relative bacteriostatic activity was, in descending order of activity, sparfloxacin, levofloxacin/ciprofloxacin and ofloxacin. These results suggest levofloxacin has potential for the treatment of pneumococcal infections.

Anti-Infective Agents↗
PubMed1999

Global left ventricular cardiac function: comparison between magnetic resonance imaging, radionuclide angiography, and contrast angiography.

RATIONALE AND OBJECTIVES: Cardiac magnetic resonance imaging (MRI) has been shown to be a robust and noninvasive method to assess left ventricular (LV) cardiac function. This study sought to assess volumes and mass calculated with MRI using fast techniques for acquisition and postprocessing, and to compare results in terms of cost-effectiveness with those of radionuclide angiography (RNA) or contrast angiography (CA). METHODS: Thirty-five patients and 15 healthy volunteers were studied. All patients underwent an MRI examination during the same period that they underwent ventriculography (26 patients) or radiography (25 patients). From 7 to 11 short-axis slices were acquired with a breath-hold fast-gradient echo-segmented sequence from apex to base. Contours were drawn with an automated border detection software. RESULTS: Ejection fraction (EF) correlated well between modalities (r = 0.77, P<0.001, for MRI and RNA; r = 0.72, P< 0.001, for MRI and CA). CONCLUSIONS: Cardiac MRI is a fast and accurate technique for estimation of LV volumes, EF, and mass.

Adult↗
PubMed1999

One dose ceftriaxone vs. ten days of amoxicillin/clavulanate therapy for acute otitis media: clinical efficacy and change in nasopharyngeal flora.

OBJECTIVE: To compare the efficacy and the safety of a single intramuscular dose of ceftriaxone, 50 mg/kg, vs. a 10-day course of amoxicillin/clavulanate (amox/clav) therapy, 80 mg/kg/day of amoxicillin: 10 mg/kg/day of clavulanate in three divided doses, in children with acute otitis media (AOM) and to evaluate the changes in nasopharyngeal flora after treatment. METHODS: In a prospective, comparative, open randomized, multicenter trial, children were scheduled to return for visits on Days 12 to 14 (main end point) and Days 28 to 42 after the beginning of treatment for AOM. A nasopharyngeal swab for bacterial culture was obtained before the treatment and at Days 12 to 14. RESULTS: Between February, 1995, and May, 1996, 513 children with a mean age of 14.2 +/- 6.7 months were enrolled. All the patients were evaluable for the safety and intent-to-treat analyses and 463 for the per protocol efficacy. At Days 12 to 14 clinical success was obtained in 186 of the 235 children (79%) given ceftriaxone and in 188 of the 228 children (82.5%) treated with amox/clav. Among the patients with clinical success on Days 12 to 14, the success was maintained at Days 28 to 42 for 108 of 183 (59%) patients in the ceftriaxone group and 103 of 187 (55%) patients in the amox/clav group. Before the antibiotic treatment the percentages of children carrying Streptococcus pneumoniae (59.1%), Haemophilus influenzae (39.4%), Moraxella catarrhalis (55.7%) and the rate of penicillin-resistant S. pneumoniae (52.2%) were comparable between the 2 groups. At Days 12 to 14 the carriage of S. pneumoniae and M. catarrhalis was significantly different between the patients treated with ceftriaxone, 43.9 and 42.2, respectively, and the patients treated with amox/clav, 17.4 and 11.1%, respectively. Among the children carrying S. pneumoniae at Days 12 to 14, the percentage of penicillin-resistant strains reached 63.4% in the ceftriaxone treatment group and 83.0% in the amox/clav treatment group, (P = 0.02). Adverse events (mainly diarrhea) related to the study medication were reported more frequently (P < 0.0001) in the amox/clav treatment group. CONCLUSIONS: In an area with a high rate of penicillin-resistant S. pneumoniae, a single dose of ceftriaxone is as efficient as a 10-day course of amox/clav in the treatment of AOM in young children. There was for the two regimens an increased rate of penicillin-resistant strains among the pneumococci carried, whereas the chance for a child to carry a penicillin resistant S. pneumoniae did not increase after treatment.

Acute Disease↗
PubMed1999

Killing activities of trovafloxacin alone and in combination with beta-lactam agents, rifampin, or vancomycin against Streptococcus pneumoniae isolates with various susceptibilities to extended-spectrum cephalosporins at concentrations clinically achievable in cerebrospinal fluid.

The killing activities of trovafloxacin alone and in combination with beta-lactam agents (extended-spectrum cephalosporins, meropenem), rifampin, or vancomycin were evaluated against 20 genotypically characterized Streptococcus pneumoniae isolates for which amoxicillin MICs were >/=4 microg/ml (cefotaxime MICs, >/=4 microg/ml for six strains) at concentrations clinically achievable in cerebrospinal fluid. At 6 h the mean killing activity of trovafloxacin alone (range, 2.6 to 2.9 log(10) CFU/ml) did not vary significantly according to the susceptibility of the strains to beta-lactam agents. The activities of trovafloxacin or vancomycin added to the beta-lactam agents and the combination trovafloxacin-vancomycin were additive or indifferent. Against the ceftriaxone-resistant isolates, the killing activity of the combination of a beta-lactam agent and trovafloxacin did not differ significantly from that of a beta-lactam agent and vancomycin.

Anti-Bacterial Agents↗
PubMed1999

Regional assessment of wall curvature and wall stress in left ventricle with magnetic resonance imaging.

Left ventricular functional abnormalities are associated with regional increases of wall stress and modifications of wall curvature. This study describes the integration of the short-axis and long-axis wall curvatures for determining peak systolic wall stress. Quantification was realized with cine magnetic resonance imaging (MRI) from the location of the endocardial and epicardial borders of the left ventricle on pairs of consecutive short-axis sections. Fifteen normal volunteers were subjected to cine MRI, and different methods of calculating peak systolic wall stress were compared. A short-axis analysis showed a 55 +/- 13% increase of the circumferential mean of the peak systolic wall stress between apical and basal sections. Regarding the curvature, no significant increase of wall stress was observed except on the septal wall (31 +/- 18%). Short-axis studies proved to be insufficient for determining the regional variations of left ventricular wall stress and for providing normal reference values for the location of abnormal regions in patients.

Adult↗
PubMed1999

[Variations of coronary blood flow measured by intracoronary doppler in the acute phase of myocardial infarction before and after revascularization by angioplasty].

The authors studied the changes in coronary blood flow before, during and after reperfusion by angioplasty of the disease coronary vessel responsible for myocardial infarction using intracoronary Doppler. Forty patients aged 60.2 +/- 15.4 years, admitted for primary myocardial infarction (inferior: 22, anterior: 18) were included. Before reperfusion, the peak velocity of the collateral coronary circulation was 14.8 +/- 8.1 cm/s. The flow was bidirectional, mainly retrograde (N = 32), negative (N = 1) or positive (N = 5). The five Rentrop 0 patients had velocities similar to Rentrop 1, 2 or 3 patients (Rentrop 0: 14.9 +/- 6.4 cm/s; Rentrop 1: 12.3 +/- 9.9 cm/s; Rentrop 2: 15.2 +/- 8.2 cm/s; Rentrop 3: 17.5 +/- 6.3 cm/s). Patients with TIMI 3 reperfusion flow had the highest APV Doppler velocities (average peak velocities during the cardiac cycle) (APV TIMI 3 = 20.2 cm/s versus APV TIMI 1 and 2 = 10.9 cm/s, p = 0.05). After angioplasty, the APV was 18.7 +/- 10.4 cm/s (p < 0.001). Diastolic flow was dominant. Seventeen patients had retrograde systolic flow, 12 had minimal systolic flow and 17 had a steep diastolic deceleration slope. Intracoronary Doppler demonstrates the wide range of coronary flow in TIMI 3 flow patients, both from the morphological and the quantitative points of view, which seems to be independent of the presence of residual stenosis and could be related to abnormalities of the microcirculation. This could allow identification of a subgroup of patients at high risk and candidates for a complementary therapeutic intervention (intra-aortic balloon pumping...).

Adult↗
PubMed1999

[MRI quantification of regional variations of left ventricular parietal stress in normal subjects].

The object of this study was to analyse regional variations in end systolic left ventricular wall stress in normal subjects using three-dimensional magnetic resonance imaging (MRI) with excellent spatial resolution. Eight to 12 contiguous short axis sections of the left ventricle were acquired from the apex to the base in apnoea with a rapid echo-gradient sequence in 15 healthy volunteers. The end systolic wall stress was calculated by three methods: Grossman's formula (CR) using the wall thickness and radius of curvature, Janz's formula (CS) using the surfaces, and a three-dimensional approach (C3D) providing a precise calculation of the radius of curvature. The values of wall stress obtained by CS and CR were lower (p < 0.001) at the apex (3.2 and 3.3 10(3) newton/m2 respectively) than at the base (6.9 and 7.1 10(3) newton/m2). There was no difference between the base and apex with the C3D method (8.0 and 9.0 10(3) newton/m2 respectively, NS). The same results were observed at the inferior, lateral, anterior and septal segments with an increase at the base using the CS and CR formulae, the C3D remaining homogeneous in the left ventricle except for the interventricular septum. The lateral wall stress was significantly lower with respect to the interventricular septum in all sections from the apex to the base, irrespective of the method of calculation used. The differences in regional wall stress from the base to the apex reported in healthy subjects seem to be related to an underestimation of left ventricular wall thickness and an underestimation of the radius of curvature rather than to a physiological phenomenon.

Adult↗
PubMed1999

[Plasma homocysteine is not a predictive factor of restenosis after coronary angioplasty].

Hyper-homocysteinaemia is a cardiovascular risk factor. In parallel, anatomopathological studies of post-angioplasty coronary restenosis show histological appearances similar to those observed in patients with severe hyper-homocysteinaemia. Based on these histological observations, the authors tried to assess the predictive value of raised plasma homocysteine levels for coronary restenosis after angioplasty. Two hundred and twenty-two patients treated by coronary angioplasty were followed up clinically for 6 months. Thallium 201 myocardial scintigraphy was performed in 179 patients and coronary angiography in 74 patients. Seventy-nine patients had coronary restenosis diagnosed by coronary angiography in 55 cases, by myocardial scintigraphy in 23 cases and strongly suspected clinically in only one patient. No significant differences in homocysteine levels were observed between patients with multiple restenosis or requiring revascularisation, and those without restenosis and not requiring revascularisation. Plasma homocysteine does not therefore seem to be a predictive factor of post-angioplasty coronary restenosis.

Aged↗
PubMed1999

Bacteriological eradication of Streptococcus pneumoniae from patients with acute exacerbations of chronic bronchitis: cefuroxime axetil versus cefixime.

The bacteriological eradication rates of Streptococcus pneumoniae from sputum of patients experiencing acute exacerbations of chronic bronchitis (WHO definition) have been compared following therapy with either cefuroxime axetil 250 mg b.d. or cefixime 200 mg b.d. All patients were hospitalised for an acute exacerbation of chronic bronchitis. The study design was a multicentre, double-blind, randomised, parallel group with patients giving written informed consent initially. Patients were recruited to the study if they met the WHO definition of chronic bronchitis, were aged 30-75 years and had a high probability of S. pneumoniae infection based on initial sputum Gram stain. All S. pneumoniae isolates were serotyped and susceptibility tested at the National Reference Centre, Paris. S. pneumoniae was eradicated more rapidly following cefuroxime axetil administration than after cefixime and this difference was statistically significant (p = 0.002) at 2-4 days post-treatment. Clinical endpoints showed a similar trend--94% response to cefuroxime axetil compared with 71% response to cefixime (RR 6.39:1). Cefuroxime eradicated S. pneumoniae significantly more rapidly than cefixime and patients in the cefuroxime axetil arm had favourable clinical criteria. The data suggest that focused antibacterial studies may be helpful in evaluating antibiotics in acute exacerbation of chronic bronchitis.

Adult↗
PubMed1998

Low dosage and long treatment duration of beta-lactam: risk factors for carriage of penicillin-resistant Streptococcus pneumoniae.

CONTEXT: The spread of drug-resistant Streptococcus pneumoniae in the community is a public health problem in developed and developing nations, but whether antibiotic use is responsible for the increase in drug resistance is not known. OBJECTIVE: To analyze the relationship between penicillin-resistant S pneumoniae (PRSp) pharyngeal carriage and characteristics of beta-lactam use. DESIGN: Observational study of children attending 20 randomly sampled schools. SETTING: The Loiret, in the center of France. PARTICIPANTS: A total of 941 children, 3 to 6 years old. MAIN OUTCOME MEASURE(S): Pharyngeal carriage of S pneumoniae, antibiotic use, and medical events during the preceding 30 days. Pneumococcal penicillin G sodium minimal inhibitory concentrations and serotyping were performed. RESULTS: Medical illnesses and the use of antibiotics were not associated with PRSp carriage. However, oral beta-lactam use was associated with an increased risk of PRSp carriage (odds ratio [OR], 3.0; 95% confidence interval [CI], 1.1-8.3; P=.03). Children treated by low daily doses of an oral beta-lactam (defined as lower than clinical recommendations) had an increased risk of PRSp carriage, as compared with children who did not (OR, 5.9; 95% CI, 2.1-16.7; P=.002). A treatment of long duration (>5 days) with a beta-lactam was associated with an increased risk of PRSp carriage (OR, 3.5; 95% CI, 1.3-9.8; P=.02). CONCLUSIONS: Our results suggest that a low daily dose and a long duration of treatment with an oral beta-lactam contribute to the selective pressure in promoting pharyngeal carriage of PRSp.

Anti-Bacterial Agents↗
PubMed1998

[Development of resistance to beta-lactams and other antibiotics of pneumococci isolated from acute otitis media in France: statement of the National Reference Center 1995-1996].

POPULATION AND METHODS: During 1995 and 1996, 393 and 566 strains of Streptococcus pneumoniae, isolated from acute otitis media, were respectively sent to the National Reference Center for Pneumococci by its corresponding centers. RESULTS: The resistance rates for 1995 and 1996 were respectively: for penicillin: 65.4 and 70.3% (18.6 and 24.9% of intermediately resistant strains, 46.8 and 45.4% of fully resistant strains), for erythromycin: 57.5 and 68.5%, for tetracycline: 43.2 and 42.6%, for trimethoprim-sulfamethoxazole: 47.5 and 50.9%. Minimal inhibitory concentrations (MICs) of various betalactams were determined against a representative sample of strains (n = 99). CONCLUSION: Amoxicillin, cefpodoxime and cefuroxime MICs remained low against numerous penicillin resistant strains, indicating that these three oral antibiotics (in combination with clavulanate for amoxicillin) have a useful potential for the treatment of acute otitis media when risk factors for pneumococcal penicillin-resistant infections are detected.

Acute Disease↗
PubMed1998

Once-daily sparfloxacin versus high-dosage amoxicillin in the treatment of community-acquired, suspected pneumococcal pneumonia in adults. Sparfloxacin European Study Group.

The objective of this randomized, double-blind, multicenter study of 329 adult patients requiring hospitalization was to compare the safety and efficacy of sparfloxacin at a dosage of 200 mg once daily (following a 400-mg loading dose on day 1) with those of amoxicillin given as a 1-g oral dose three times daily for treatment of community-acquired pneumonia suspected to be due to Streptococcus pneumoniae. Success of treatment was determined by a combination of clinical assessment and chest radiography. Pneumococcal pneumonia was the confirmed diagnosis for 177 patients (54%). Overall rates of success among evaluable patients were equivalent between drugs, both at the end of treatment (sparfloxacin, 92%; amoxicillin, 87%) and at follow-up (sparfloxacin, 89%; amoxicillin, 84%). Sparfloxacin was well-tolerated and produced fewer gastrointestinal effects than amoxicillin. In conclusion, sparfloxacin is a safe and effective alternative to high-dose amoxicillin for the treatment of suspected pneumococcal community-acquired pneumonia.

Adult↗
PubMed1998

Effects of cefixime or co-amoxiclav treatment on nasopharyngeal carriage of Streptococcus pneumoniae and Haemophilus influenzae in children with acute otitis media.

A multicentre, open-label, randomized study was performed in 501 out-patients with acute otitis media, aged 6-36 months, to study the impact of treatment with either cefixime suspension 8 mg/kg/day bd or co-amoxiclav suspension 80 mg/kg/day tds for 10 days on nasopharyngeal carriage of Streptococcus pneumoniae and Haemophilus influenzae. Of 426 patients with nasopharyngeal cultures at entry to the trial, end of treatment and at follow-up visit (35 days after inclusion), significant changes in carriage of S. pneumoniae were observed. The proportion of penicillin-resistant S. pneumoniae was higher in the samples taken at the end of treatment and follow-up than in those taken at inclusion, while the total number of children with this microorganism was lower. The difference at the end of treatment was greater with co-amoxiclav than with cefixime. For H. influenzae the resistance rate remained steady while the number of children with this microorganism decreased. At follow-up there was no significant difference between the two groups in terms of nasopharyngeal positive culture for S. pneumoniae or H. influenzae. Despite these differences, successful clinical responses were similar at the end of treatment and at follow-up.

Amoxicillin-Potassium Clavulanate Combination↗