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Biomedical subjects

G Chéron

Publications and source records attributed to G Chéron.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Smoking and sudden infant death syndrome].

Assessment of the causation relationship between two phenomena requires the demonstration of an epidemiological association, a temporal and asymmetric sequence, and a biological gradient and identification of the biological mechanism(s). All epidemiological studies on sudden infant death syndrome (SIDS) and smoking have encountered major bias and difficult data interpretation but they all have estimated that maternal smoking caused a 2 to 3-fold increased risk of SIDS. Nicotine may interact with non-neuronal nicotinic receptors in the lung, peripheral nicotinic cholinergic and adrenergic chemoreceptors, and brainstem nuclei and has been largely studied. More accurate knowledge concerning the biochemistry and specific features of nicotinic receptors will be useful to explain the way nicotine alters breathing at rest and during hypoxia. Uncertainty about the casual relationship in no way means the fight against smoking is not warranted.

Bias↗
PubMed2003

[Angelman syndrome: clinical and genetic model].

Angelman syndrome is a neurogenetic disorder characterized by developmental delay, absence of speech, motor impairment, epilepsy and a peculiar behavioural phenotype associated with abnormalities of chromosome 15q11-13. Precise diagnosis carries clinical and genetic counseling implications. However, many clinicians still seem unfamiliar with it despite the severity and typical aspects of presentation. Beyond individual situations, Angelman syndrome can serve as a model opening broad questioning of genetic and epigenetic influences in neurology, as well as of several concepts such as psychomotor development, cerebral palsy, behavioural phenotypes and epileptic syndromes. Recent advances in molecular biology and animal models of the syndrome provide new data which must be included in our interpretation of Angelman syndrome.

Angelman Syndrome↗
PubMed2002

[Benefits of ipratropium bromide in the management of asthmatic crises in the emergency department].

BACKGROUND: To determine if the addition of ipratropium bromide in the emergency department (ED) for the treatment of childhood asthma reduces rates of hospitalization and relapses for moderate and severe exacerbations. METHODS: Patients were given an oral corticosteroid treatment (2 mg/kg) and received every 20 minutes either three nebulizations with albuterol (0.15 mg/kg) and ipratropium bromide (250 micrograms) or six nebulizations with albuterol alone (control group). The primary end point was the need for hospitalization, additional nebulizations or a relapse during the following week. Secondary end point included the effect of age. RESULTS: One hundred and forty three children, two to 15 years old, were randomized to ipratropium or control groups and 121 were evaluated on day seven. As a whole, the control group was less often hospitalized or in relapse than those treated with three nebulizations of albuterol and ipratropium (17.5% vs 37.9%, p < 0.02). The ipratropium group reached the same result after three additional albuterol nebulizations. The benefit of anticholinergic therapy was observed for children less than six years of age who had a similar rate of success (73.5 vs 75.7%). CONCLUSION: The association of ipratropium bromide to the first three doses of the albuterol protocol for acute asthma did not act as well as six nebulizations of albuterol alone. The effect was age dependent and two to six years old children needed more attention. Nevertheless the hospitalization rate did not support the use of ipratropium compared with repeated albuterol nebulizations.

Adolescent↗
PubMed2002

[Effect of racecadotril in the management of acute diarrhea in infants and children].

BACKGROUND: The treatment of diarrhoea relies on the maintenance or restoration of hydration with maintenance of an adequate nutritional intake. Racecadotril has been shown to reduce the stools output during acute diarrhoea. The present work was aimed at measuring the number of emergency department visits for acute diarrhoea either the children received racecadotril or not. METHOD: Racecadotril and rehydration were compared with rehydration alone in children aged three months to three years who had acute diarrhoea and were evaluated in the emergency department (ED). The primary end point was the number of medical exams during the week after starting treatment. Secondary end points were the number of stools during the first 48 hours, the duration of the diarrhoea and the weight on day 7. RESULTS: One hundred and sixty-six children were alternatively randomized to the treated and the control groups. There was no difference for age, degree of dehydration and length of illness before the first visit between the groups. Whatever type of rehydration (oral or i.v.), the treated group had a significant lower number of stools (p < 0.001) and a faster recovery (p < 10(-9)). The children receiving racecadotril needed less additional ED visits for the same episode (p < 0.05). There was no difference for the weight-gain on day 7. CONCLUSIONS: This study demonstrates the efficacy of racecadotril as adjuvant therapy to oral and i.v. rehydration in the treatment of acute diarrhoea and a fewer emergency department second visit before recovery.

Acute Disease↗
PubMed2002

[Mucolytic agents for acute respiratory tract infections in infants: a pharmacoepidemiologic problem?].

OBJECTIVE: To study the use of mucolytics agents, i.e. acetylcystein and carbocystein, in infants. To evaluate their efficacy and safety for their main indications. METHODS: A prospective one-day survey of prescriptions among 95 office-based pediatricians. A systematic review of the literature. RESULTS: Among 1327 prescriptions regarding infants, 4.3% were mucolytics agents. Main indications were rhinopharyngitis, isolated cough, and acute bronchitis. Our review did not identify any study of rigorous methodological quality that supported the efficacy or safety of mucolytics agents in infants for their in-label (isolated cough, acute bronchitis) and off-label (rhinopharyngitis) indications. Six cases of infants, aged less than eight months, presenting paradoxical bronchial congestion during a treatment with mucolytics agents, have been reported to the French pharmacovigilance system. No causal relationship was established from these cases because of a possible protopathic bias. DISCUSSION: Our results concerning mucolytics agents use are similar to those reported by the French Health Care Funds. In addition to the lack of studies on efficacy, no studies on the dose-response relationship were available, leading to suggested dose regimens in the French license of acetylcystein ranging from 44.4 to 16.4 mg kg-1 j-1 between one to 24 months. These dose regimens could predispose to overdosing in the youngest infants as it seems observed in the six reported cases. CONCLUSION: In infants, mucolytics agents efficacy has never been demonstrated and some elements suggest poor safety (paradoxical bronchial congestion).

Acetylcysteine↗
PubMed2001

[Drugs for pediatric emergencies].

Drugs for pediatric emergencies are useful for respiratory (croup, asthma), cardiologic (hypertensive crisis, acute congestive heart failure, arrhythmias, hypoxic spells), neurologic (seizures), metabolic (dehydration, hypoglycaemia), infectious (meningococcemia) or allergic (anaphylaxis) distresses. Pain management is always important whether to relieve or to prevent the discomfort which would happen during diagnosis or therapeutic procedures.

Cardiovascular Diseases↗
PubMed2001

[Assessing the cost of the first episode of bronchiolitis].

BACKGROUND: Each year, a quarter of the children younger than 24 months has respiratory syncytial virus bronchiolitis. The morbidity among high-risk infants and the possible association with the development of asthma lead to propose preventive measures whose cost-effectiveness relationship is unknown. The present work was aimed at measuring costs of a first attack of bronchiolitis. METHOD: For children less than two years visited in the emergency department, direct and indirect costs were measured according to the 'Sécurité Sociale' prices. Associated morbidity, the management of care (inpatient versus outpatient), outpatients' outcome two weeks after the visit, socioeconomic data were recorded. RESULTS: One hundred eighty three children have been studied. The length of stay for 40 hospitalizations was 7.6 +/- 4.3 days. Direct costs were 37,200 +/- 22,000 FF for inpatients, and 1286 +/- 633 F for outpatients. For 113 outpatients' families, indirect costs were 49 working days lost. The way the child was looked after and the unemployment rate in the study were similar to data provided by the National Institute of Statistics and Economic Studies. CONCLUSION: Because of the variability of the hospitalization rate from one setting to another, overall costs of the epidemic cannot be evaluated. For the policymaker, the greatest costs come from the outpatient care. Others studies will be necessary to evaluate the price of future preventive measures.

Bronchiolitis↗
PubMed2000

[Infant diseases].

Apparent life-threatening events in an infant require: 1/ to determine the seriousness of the event; 2/ to identify its etiology; 3/ to evaluate the risk of recurrence and the need for appropriate preventive measures. Management mainly depends upon the determination of the etiology and the understanding of the pathogenetic mechanism. Gastroesophageal reflux is the main etiology. Therefore whenever symptoms of gastroesophageal reflux are present, this has to be considered as the first etiological hypothesis. Other etiologies will be searched for if orientating symptoms or anamnesis information is present, leading to specific investigations.

Bradycardia↗
PubMed2000

Off label and unlicensed drug use among French office based paediatricians.

AIMS: To determine the extent of off label and unlicensed drug use in French office based paediatric practice. METHODS: A prospective one day survey of all written prescriptions, for patients under 15 years, among 95 office based paediatricians in the Paris, France metropolitan area. Main outcome measures were: comparison of the use of each drug with its product licence for age, indication, dose, and route of administration. RESULTS: A total of 2522 prescriptions were administered to 989 patients; 844 (33%) were used either in an unlicensed (4%) or an off label (29%) manner. A total of 550 (56%) paediatric patients received one or more off label prescriptions. CONCLUSIONS: Off label prescriptions (that is, outside the terms of the Summary of Product Characteristics) are widespread in office based paediatric practice, while unlicensed drug use is rare in our study. New regulations in the licensing process in Europe are needed to allow children to receive drugs that have been fully evaluated in their specific age group.

Adolescent↗
PubMed2000

Ontogenesis of CYP2C-dependent arachidonic acid metabolism in the human liver: relationship with sudden infant death syndrome.

A modification of the human monooxygenase system have been previously associated with the sudden infant death syndrome (SIDS): the hepatic CYP2C content was markedly enhanced and resulted from an activation of CYP2C gene transcription. To determine the possible consequence of the up-regulation of CYP2C in SIDS, we examined the metabolism of arachidonic acid (AA) an endogenous substrate of CYP2C involved in the physiologic regulation of vascular tone. The overall AA metabolism was extremely low during the fetal period and rose after birth to generate 14,15 epoxyeicosatrienoic acid (EET), 11,12 EET and the sum of 5,6 dihydroxyeicosatrienoic acid (diHETE)+omega/omega-1 hydroxy AA. In SIDS, the accumulation of CYP2C proteins was associated with a significant increase in the formation of 14,15 and 11,12 diHETE, which were shown to be supported by individually expressed CYP2C8 and 2C9 and HETE1 (presumably 15 HETE). This increase was markedly inhibited by addition of sulfaphenazole, a selective inhibitor of CYP2C9. So, we propose that the higher CYP2C content in SIDS stimulates the production of EETs and diHETEs and might have severe pathologic consequences in children.

8,11,14-Eicosatrienoic Acid↗
PubMed1998

[Epidemiologic survey of infants hospitalized for bronchiolitis. Survey conducted by the ERBUS medical network].

BACKGROUND: Acute infant bronchiolitis is a frequent seasonal disease which peaks in December. It often requires hospital care in Paris and in its surroundings. The exceptional bronchiolitis epidemic of December 1991 brought about a temporary saturation of hospital bed space at the Assistance Publique-Hôpitaux de Paris (AP-HP). Hereafter, in order to organize care more efficiently, an epidemiological observation network called ERBUS was set up. METHODS: Thanks to daily reports of emergency pediatric admissions through the Minitel network, it has been possible to get real time information on the course of the past five epidemics in each of the 11 AP-HP hospitals with pediatric emergency units. RESULTS: Globally the results point to a similar situation every year: approximately 60% boys, 35% babies under 6 months; the ratio of very young patients who are admitted to hospital is multiplied by 1.5 at the mid-point of and at the end of the epidemic compared with the beginning; 70% of the babies under 3 months are admitted to hospital. The ratio of patients who come and are admitted to hospital has been on the decrease every year since 1991: globally from 36.8% down to 28.6% in five years (from 75.1% down to 65.3% among babies under 3 months). The rhythm and intensity of the epidemic have risen sharply: in five years, the number of patients has increased by 119% and that of patients admitted to hospital by 69%, while the epidemic peaks are earlier and higher. CONCLUSION: These statistics have actually been used to allocate additional resources in AP-HP hospitals during the epidemics. To avoid the saturation of bed space in the future, ambulatory care of patients not admitted to hospital should be favored.

Bronchiolitis↗