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F Leclerc

Publications and source records attributed to F Leclerc.

At least 73 records · Page 4Linked to original sources
PubMed1997

[Characteristics of patients and use of resource in French pediatric intensive care units. Le groupe francophone de Rèanimation et urgences pédiatriques].

UNLABELLED: Evaluation of case-mix and resource consumption in pediatric intensive care units (ICU) is required. AIMS: This study describes the patterns of pediatric ICU resource consumption, determines the impact of primary clinical characteristics (particularly severity of illness) on resource utilization, and analyses medical efficiency with the frequency of inappropriate stays in French pediatric ICU. METHODS: Prospective study in nine French volunteer multidisciplinary pediatric ICUs from December 1993 to April 1994. Premature neonates were excluded. Resource consumption was expressed using the Omega system and length of stay, from which total Omega per admission, and average daily Omega (total Omega/length of stay) were obtained. RESULTS: Seven hundred and twelve patients were eligible. Twenty-five percent were full-term neonates, 30% infants (1 month to 1 year), and 45% children. Surgical patients constituted 22% of the population. A chronic disease was present in 45% of infants and children. Immunodeficiency was present in 10% of patients. The median length of stay was 4 days (range: 1-155). The mean Omega scores per admission were: total Omega = 92 +/- 124, Omega/day = 14 +/- 9. Sixty-four percent required mechanical ventilation and 37% during more than 2 days. Forty-two percent had a central venous access, and 23% an arterial line. The resource consumption was greater in non-survivors, surgical patients, neonates, and immunosuppressed patients. The mean PRISM score was 9 +/- 9. Mortality was 13%. The Omega/day and the PRISM score correlated. The frequency of inappropriate stays was 7.6% and accounted for 1.0% of the overall Omega activity. CONCLUSIONS: The results of this study can be used for interinstitutional comparison and a broader appraisal of pediatric intensive care. They illustrate the relationship between severity of illness and resource consumption. French pediatric ICU efficiency seems to be high, as compared to North American and Dutch results.

Adolescent↗
PubMed1997

[Evaluation of the ambulatory treatment of acute diarrhea in infants. Réseau interhospitalier d'evaluation des pratigues médicales dans les affections courantes de l'enfant].

BACKGROUND: Gastroenteritis remains a common and expensive illness. Oral rehydration solutions (ORS) have been shown to be effective in the prevention and treatment of dehydration, the prime cause for diarrhea-related morbidity and mortality. OBJECTIVE: To evaluate the ambulatory management of acute gastroenteritis in infants, and particularly practices concerning oral fluid therapy. METHODS: This prospective, multicenter study included 326 infants (mean age: 10 +/- 6 months), examined in a hospital for acute gastroenteritis, with or without dehydration. RESULTS: Before admission, 81% had previously been examined by a practitioner, and 89% of these practitioners had written a prescription. This prescription included ORS in 35% and was not different according to the age of the infant. Pediatricians prescribed ORS more frequently than general practitioners (respectively 58% vs 29%; P < 0.001). The failure rate of ORS prescription was 25% (two parents did not observe, ten children refused to drink, and eight stopped treatment because of vomiting). Lactose-free milks were prescribed in 46% of infants and the observance was 82%. At least one drug was prescribed in 94% of infants, with a mean of 2.6 drugs per infant; one antibiotic was prescribed in 33% of infants. Infants were admitted to hospital without any previous consultation in 18%, on the parents' initiative but after at least one previous medical examination in 52%, and on the physician's initiative in 30%. Thirty-three percent were dehydrated; one infant died and two had sequellae. CONCLUSION: The use of ORS remains insufficient. Efforts to improve use of ORS should be expanded beyond physician education.

Acute Disease↗
PubMed1997

[Acute respiratory insufficiency revealing myasthenia gravis: apropos of 3 cases].

BACKGROUND: Myasthenia gravis is usually revealed by a ptosis or a diplopia. A respiratory muscle weakness often occurs during the course but an acute respiratory failure as initial feature is unusual. CASE REPORTS: Three girls, aged 8, 10 and 14 years, were hospitalised in an intensive care unit, along a 15 year-period, for an acute respiratory distress. The first two children suffered from skeletal and bulbar muscle weakness. The third, admitted with the diagnosis of unexplained pneumonia, was complaining of skeletal and bulbar muscle weakness for the last 18 months. Myasthenia gravis was confirmed with electromyography, and detection of the acetylcholine-receptors antibodies in all three cases. CONCLUSION: Any unexplained acute respiratory distress must lead to search for skeletal and bulbar muscle weakness, specially after muscular exercise or at the end of day, manifestations which characterize myasthenia gravis.

Acute Disease↗
PubMed1997

Predicting RNA structures: the model of the RNA element binding Rev meets the NMR structure.

BACKGROUND: How accurate are the predictions of RNA three-dimensional structures? Assessing this accuracy requires the detailed comparison of the prediction with the experimentally determined structure. Previously, sequence variation in RNA aptamers that bind the Rev protein was used to infer a three-dimensional model of the Rev-binding element (RBE) RNA. Although much of this model has been substantiated by subsequent experimental data, its validity remains to be determined by confronting it with the structure determined by NMR spectroscopy. RESULTS: A series of different criteria such as geometric parameters (root mean square deviation, interproton distances, torsions and puckering), helicoidal parameters (base pairing and base stacking) and stability considerations (conformational energies) have been evaluated to identify common and distinguishing structural characteristics of the model and the NMR structure. CONCLUSIONS: The detailed comparison of the two structures reveals striking structural similarities at both the global and local level that validate the RNA modeling approach that we have used. Analysis of the structural differences and the precision of the model suggest that the limitations of the method are related to the amount of structural information available for modeling.

Binding Sites↗
PubMed1997

Laryngotracheal stenosis in children after intubation. Report of five cases.

Acquired laryngotracheal stenosis is a serious long term complication of tracheal intubation with an incidence of 0.7 to 8% in intubated children. We report five cases of subglottic stenosis over a 4.5-year period and review the pathology and pathogenesis of the condition. A diagnosis of subglottic stenosis was suspected when extubation failed due to the onset of dyspnoea or laryngeal stridor. An incidence of 0.9% of all intubated children was observed. We conclude that the main components contributing to stenosis are pathologies with decreased mucosal capillary perfusion pressure and intubation conditions.

Child, Preschool↗
PubMed1997

Indications for flexible versus rigid bronchoscopy in children with suspected foreign-body aspiration.

Diagnostic indications for flexible bronchoscopy in the initial investigation of children with suspected foreign-body (FB) aspiration have not been evaluated prospectively. We prospectively collected history, clinical, and radiologic findings at prebronchoscopic examination of all children referred for suspected FB aspiration between February 1993 and September 1995. Children with asphyxiating FB aspiration, requiring immediate rigid bronchoscopy, were excluded. If there was clear evidence of FB aspiration from the physical and radiographic findings, rigid bronchoscopy was directly performed. If the evidence was not convincing, children underwent diagnostic flexible bronchoscopy under local anesthesia. If an FB was found, rigid bronchoscopy was always performed for extraction. Eighty-three consecutive children (median age: 24 mo) were included. Among 28 who underwent rigid bronchoscopy first, 23 had an FB. Among the 55 children who underwent flexible bronchoscopy first, 17 had an FB. Predictive signs of a bronchial FB were a radiopaque FB, and associated unilaterally decreased breath sounds and obstructive emphysema (positive predictive value = 0.94). We propose the following management algorithm: Rigid bronchoscopy is performed first in case of asphyxia, a radiopaque FB, or association of unilaterally decreased breath sounds and obstructive emphysema. In any other case, flexible bronchoscopy is performed first for diagnostic purposes. If applied retrospectively to the 83 children in our study, this algorithm would have decreased the negative first rigid bronchoscopy rate to 4%. Flexible bronchoscopy is a safe and cost-saving diagnostic procedure in children with suspected FB aspiration.

Algorithms↗
PubMed1996

[Bronchial mucoepidermoid carcinoma: apropos of 3 cases].

BACKGROUND: Mucoepidermoïd carcinomas (MEC) are very rare (less than 20 cases reported in the literature) and potentially malignant bronchial gland carcinomas. PATIENTS: Three children, two boys (11 and 7 years old) and one girl (5 years old) suffered from respiratory symptoms such as cough, recurrent pneumonia and/or hemoptysis for 2 to 12 months. Bronchial endoscopy showed a mass into the left (two cases), or the right main bronchus (one case). Chest CT scan identified local extension, and lung-associated lesions. Histopathological study concluded to MEC in the three cases. The patients were treated by segmental bronchial resection, completed with left upper lobectomy (two cases), bronchotomy (one case). All the tumor could be removed; there was no metastasis. The outcome was uneventful with a 8 to 24 months follow-up. CONCLUSION: Bronchial tumors of children must be considered in patients with chronic cough, recurrent pneumonia and/or hemoptysis and require bronchial endoscopy for their diagnosis.

Bronchial Neoplasms↗
PubMed1996

Using SAR and QSAR analysis to model the activity and structure of the quinolone-DNA complex.

A set of 78 quinolone derivatives were used in a structure-activity study to identify structural features correlating with antibacterial activity. Distinct combinations of functional properties were identified for Gram-negative and Gram-positive bacteria. 3-D Quantitative structure-activity relationship (QSAR) studies identified specific hydrophobic, topologic and electronic properties of the molecules for both in vitro and in vivo activities. From these results, a three-dimensional model of a DNA-quinolone complex was built using molecular modeling techniques. It was based on the intercalation of quinolone into the double helix of DNA. We conclude that the intercalation model is consistent with most available data on the structure of the quinolone complex. This predicted structure is stabilized by the binding of magnesium ion with the sp2 oxygens present in quinolone, a phosphate and a purine base of the DNA. Substituents R1 and R7 are predicted to make hydrophobic interactions in the major and minor groove of DNA, respectively. R7 could also form hydrogen bonds with amino groups of guanines and the aspartic acid residue at position 87 in DNA gyrase subunit A.

DNA Topoisomerases, Type II↗
PubMed1996

Spondylodiscitis and mediastinitis after esophageal perforation owing to a swallowed radiolucent foreign body.

A 6-year-old boy with aphagia presented with a radiolucent foreign body, esophageal perforation, mediastinitis, and a C6-C7 spondylodiscitis. A rigid plastic gear wheel was removed via thoracotomy, and the mediastinal abscess was drained through the esophagomediastinal fistula. Treatment included antibiotics as well as nonsurgical orthopedic management of the spondylodiscitis. The recovery period was uneventful, and the patient has remained asymptomatic for 2 years. Physicians must be aware of radiolucent foreign bodies. Computed tomography is very helpful in establishing the diagnosis of radiolucent foreign body, mediastinal abscess, and spondylodiscitis.

Abscess↗
PubMed1996

A docking and modelling strategy for peptide-RNA complexes: applications to BIV Tat-TAR and HIV Rev-RBE.

BACKGROUND: In spite of the great interest in the interaction between RNAs and proteins, no general protocol for modelling these complexes is presently available. This methodological vacuum is particularly acute because the structure of few such complexes is known. RESULTS: A general strategy for docking and modelling RNA-protein complexes has been developed. The docking procedure involves minimizing electrostatic and van der Waals' interaction energies of conformationally rigid structures during docking. After docking, libraries of amino acid sidechain conformations are searched to obtain the best interactions between the peptide and the RNA. Using this method, we have reproduced the structure of a bovine immunodeficiency virus (BIV) Tat peptide bound to BIV TAR RNA and have developed a model for the structure of the arginine-rich HIV-1 Rev peptide (Rev34-50) interacting with the Rev-binding element (RBE). CONCLUSIONS: The resulting model of the Rev34-50-RBE complex predicts that although no single arginine sidechain is responsible for complex formation, residues Arg2, Arg5 and Arg11 are more important for binding than the other arginine residues in the peptide. One model is supported by binding measurements performed on wild-type and mutant RBE molecules with the peptide.

Animals↗