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E Chevalier

Publications and source records attributed to E Chevalier.

18 recordsLinked to original sources
PubMed2003

[Infections by Candida sp. in intensive care. Survey of French practices].

OBJECTIVE: The isolation of Candida sp in nosocomial infections is on the increase and over the past 10 years many guidelines for "good" practices and recommendations have been published on the modalities for the management of systemic candidiasis. The aim of this paper was to assess the habits in the intensive care units in this domain in France. METHOD: A transversal survey on the habits was conducted from March to May 2001, using a questionnaire mailed to 200 intensive care units. RESULTS: One hundred eighty questionnaires (surgical reanimation: 12%, medical: 18%, medico-surgical: 70%) out of 200 (92.5%) were returned. The indirect diagnostic examinations: serology, search for antigenemia and PCR (Polymerase Chain Reaction) were never used in 21, 35 and 65% of cases. The systematic search for colonisation (a mean of 4 areas sampled) was conducted in all the patients by 19% of the investigators, in some patients by 53%, and never by 28%. An antifungal treatment was prescribed: in the presence of a positive haemoculture alone, once out of twice if the sample had been taken from a central catheter and in 2 cases out of 3 when the sample was peripheral. It was prescribed 6 times out of 10 after isolation of Candida sp following surgery or on needle aspiration of an intra-abdominal abscess, varyingly in the case of cadiduria, isolation of a Candida sp in a broncho-pulmonary sample or in abdominal draining and positive culture of a catheter, depending on the intensity of the colonisation, the severity of the clinical picture and the presence of factors of risk for Candida infection. It is still prescribed empirically depending on the same elements and the absence of explanation for worsening. When faced with candidemia in a non-neutropenic patient, a central catheter is not changed in 18% of cases. Depending on the microbiology, fluconazole is prescribed in: the identification of yeast without further precision (78% of cases), Candida sp without further precision (86% of cases), Candida non albicans without further precision (57% of cases), C. albicans (93% of cases), Candida non albicans other than C. krusei and C. glabrata (62% of cases), C. glabrata (36% of cases) with an increase in dose in 1 out of 2 cases. In the presence of C. glabrata or C. krusei, amphotericin B is the choice in respectively 51 and 75% of cases. To adapt the treatment.

Adult↗
PubMed1999

Excitatory granule cells of the dentate gyrus exhibit a double inhibitory neurochemical content after intrahippocampal administration of kainate in adult mice.

We have previously demonstrated that, in the adult mouse, injection of kainate/AMPA receptors agonists into the dorsal hippocampus induces major structural modifications of the dentate gyrus granule cells. Such changes are mediated by the brain-derived neurotrophic factor (BDNF). Considering previous involvements of BDNF in activity-linked regulations of hippocampal neuronal phenotype, changes of neurochemical contents were further investigated. It is shown that excitatory granule cells rapidly acquire a strong immunoreactivity for the inhibitory neurotransmitters GABA and neuropeptide-Y, with different patterns for both molecules. GABA immunoreactivity appeared first in mossy fibers, before extending to cell bodies and dendrites. Analysis of glutamic acid decarboxylase revealed slight increases in mossy fibers and no somatic labeling. In contrast to GABA, neuropeptide-Y labeling was observed first in granule cell soma and then in mossy fibers, with a centrifugal gradient. All labelings were transient, but slight amounts of GABA and NPY were kept in some cell bodies for at least 6 months. Confocal microscope analysis of double GABA/NPY labelings revealed colocalization of both mediators in the same neurons. The specificity of kainate-linked changes was suggested by lack of immunoreactivity for somatostatin. These results show that the capacities of mature granule cells to adapt environmental modifications can concern neurochemical contents, by synthesis and/or uptake of specific molecules. The fact that adaptive changes are rapid and transient suggests a direct response to kainate, in order to limit its potentially deleterious effects. Colocalization of GABA and neuropeptide-Y indicates that the dentate gyrus granule cells can use several pathways to this aim.

Age Factors↗
PubMed1999

Reduction of ischemic damage in NGF-transgenic mice: correlation with enhancement of antioxidant enzyme activities.

If permanent focal ischemia is induced by middle cerebral artery occlusion (MCAO), neurons within the infarcted territory die by necrosis and apoptosis (or programmed cell death). We have previously shown, using a mouse strain transgenic (tg) for the nerve growth factor (NGF) gene, that tg mice have consistently smaller infarcted areas than wild-type (wt) animals, correlated with upregulated NGF synthesis and impaired apoptotic cell death. We studied, in wt and tg mice subjected to MCAO, the activities of several antioxidant enzymes and the synthesis of the proteins of the Bcl-2 family. Our results show that the antiapoptotic Bcl-2 protein and glutathione peroxidase are recruited after MCAO. NGF-tg mice also had an intrinsic resistance to oxidative stress because their basal copper zinc superoxide dismutase (SOD) and glutathione transferase activities were high. Additionally, manganese SOD activity increased in NGF-tg mice after MCAO, correlating strongly with the resistance of these mice to apoptosis.

Animals↗
PubMed1998

[Atypical involvement of undifferentiated carcinomas of the nasopharyngeal type. Apropos of 3 cases].

We report 3 cases of undifferentiated carcinomas of nasopharyngeal type (UCNT) found in unusual sites and compare them with histologically identical tumors found in the nasopharynx. Using viral serology and viral marquers found in the tumor cells, we looked for a link with the Epstein Barr Virus (EBV) which exists in the nasopharyngeal site. It appears that UCNT found in unusual sites have a poorer prognostic than the same nasopharyngeal tumors; no link was found with EBV. The number of published cases is too small to form a conclusion, therefore, we propose a systematic search for EBV, presenting our protocol, each time is discovered UCNT in an unusual site.

Aged↗
PubMed1998

[Use of endoscopy in pituitary surgery].

Endoscopy has changed many of surgical procedures concerning nasal and paranasal cavities. It has been proposed for transnasal removal of pituitary adenomas. The authors report their experience concerning four pituitary macroadenomas operated with the neurosurgical team of Sainte-Anne hospital. The endonasal trans-septal route seemed to be more anatomical and less traumatic than the rhinoseptal sublabial route. The 30 degrees rigid Hopkins endoscope was a good help for controlling the absence of any tumor remnant in the supra and parasellar regions after complete removal of the tumor performed through the endoscope or with the operating microscope. The authors discuss the advantages and limitations of such endoscopic procedures in the light of recent literature.

Adenoma↗
PubMed1998

[Atelectasis of the maxillary sinus. Analysis of progression stages. Apropos of 4 cases].

We analyzed atelectasic processes occurring in the maxillary sinus. Several publications in the literature have tempted to analyze the pathogenesis. Clinically the processes are often silent and only revealed when the major opthalmological complication, enophthalmia, becomes patent. In other cases there is a long history of chronic sinusitis. There is a spectacular retraction of the maxillary sinus walls leading to collapse of the orbital floor and enophthalmia. We report four cases of maxillary sinusitis with atelectasia of the sinus walls at different stages of progression. These observations and data in the literature emphasize the importance, whatever the state of development, of endoscopic osteal decompression to avoid ophthalmological complications.

Adolescent↗
PubMed1997

Involvement of prostaglandins and CGRP-dependent sensory afferents in peritoneal irritation-induced visceral pain.

This study investigates the contribution of prostaglandins (PG) and calcitonin gene-related peptide (CGRP) pathways in visceral pain induced by peritoneal irritation in rats. Peritoneal irritation was produced by i.p. administration of acetic acid (AA: 0.06-1.0%, 10 ml/kg). Visceral pain was scored by counting abdominal contractions. The effect of CGRP (3-100 microg/kg, i.p.) was also evaluated. Like AA, CGRP induced abdominal pain. Neonatal pretreatment with capsaicin reduced abdominal contractions produced by AA (0.6%) and CGRP (20 microg/kg) with 64.6% and 45.6%, respectively. Abdominal contractions induced by AA and CGRP were blocked by two antinociceptive drugs, mu-and kappa-opioid agonists, morphine and (+/-)-U-50,488H, respectively. Indomethacin (3 mg/kg, s.c.) reduced the number of abdominal contractions produced by AA by 78.1%+/-6.4% but did not inhibit abdominal contractions produced by CGRP. The CGRP, receptor antagonist, hCGRP(8-37) (300 microg/kg, i.v.) inhibited AA- and CGRP-induced abdominal contractions with 57.5%+/-12.4% and 51.6%+/-11.3%, respectively. Concomitant i.p. administration of PGE1 and PGE2 (0.3 mg/kg of each) produced abdominal contractions which were inhibited 45.6%+/-9.3% by hCGRP(8-37) (300 microg/kg i.v.). Taken together, these results suggest that peritoneal irritation is likely to trigger the release of prostaglandins, which in turn produces a release of CGRP from primary sensory afferents.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗
PubMed1997

Reversal by kappa-agonists of peritoneal irritation-induced ileus and visceral pain in rats.

Peritoneal irritation in rats induced by i.p. administration of acetic acid produces abdominal contractions reflecting visceral pain, and gastrointestinal ileus characterized by inhibition of gastric emptying and small intestine transit. In this study, gastric emptying (GE) and intestinal transit, calculated by the geometric center (GC) method, were estimated using a test meal labeled with 51Cr-EDTA. Visceral pain was assessed by counting abdominal contractions. Acetic acid produced abdominal contractions (80.8 +/- 3.3) and inhibition of GE (-54%) and GC (-63%) during the test-period. The kappa-opioid receptor agonists, CI-977 (+/-)-U-50,488H, (+/-)-bremazocine, PD-117,302, (-)-cyclazocine, and U-69,583, reversed abdominal contractions and inhibitions of gastrointestinal transit in a dose-related manner. The mu-opioid receptor agonists and potent analgesics, morphine and fentanyl did not restore normal gastric emptying and intestinal transit. These data suggest that selective kappa-opioid receptor agonists might be used to treat abdominal pain associated with motility and transit impairment during postoperative ileus.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗
PubMed1996

[Osteoma of the naso-sinusal cavities. Surgical indications and role of endonasal endoscopic surgery].

Osteoma of the para-nasal sinuses is a rare and benign tumor that develops slowly. When therapy becomes mandatory, it is necessarily surgical and requires a standard external approach. This report analyses seven cases of operated osteomas, using different surgical techniques, adapted to different indications. Three patients underwent exclusive endonasal endoscopic surgery, and four patients had external surgery coupled with endonasal surgery. Results have proven successful with a four-year median follow-up. Epidemiological, clinical, histological and therapeutic considerations as well as the value of the endoscopic endonasal surgical approach are discussed. Endonasal endoscopic surgery can be used alone in naso-ethmoidal osteomas. It must, though, be associated with external standard procedure when the osteoma involves important extension to the frontal sinuses. In isolated frontal osteomas, external standard approach is mandatory for resection, endonasal technique being in this case contributive to the repermeabilisation of the infundibulum.

Adult↗
PubMed1994

[Ear dressings].

Explore the source record for details and available documents.

Bandages↗
PubMed1994

Fedotozine reversal of peritoneal-irritation-induced ileus in rats: possible peripheral action on sensory afferents.

Two kappa agonists, fedotozine and trans-(+/-)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolydinyl)-cyclohexyl ]- benzeneacetamide methanesulfonate [(+/-)U-50,488H] were used to reverse the gastrointestinal transit inhibition induced by either peritoneal irritation (PI) or intracisternal (i.c.) administration of corticotropin releasing factor (CRF). PI was induced by acetic acid given i.p. Gastric emptying and intestinal transit were estimated with a 51Cr-labeled test meal. PI inhibited both gastric emptying (-50.9%) and intestinal transit (-48.8%). These inhibitions were prevented in a dose-dependent manner by the CRF antagonist, alpha-helical-CRF9-41 at doses (1-10 nmol/rat i.c.) that had no effect in control animals. CRF (300 pmol/rat i.c.) reproduced the gastrointestinal transit inhibitions seen under PI. The CRF effects were blocked by alpha-helical-CRF9-41 (10 nmol/rat) given i.c. but not i.v. Fedotozine (1-10 mg/kg s.c. but not 300 micrograms/rat i.c.v. or intrathecally) and (+/-)U-50,488H (0.3-3 mg/kg s.c. but not 100 micrograms/kg i.c.v.) reversed PI- but not CRF-induced ileus. Neither PI-induced ileus nor the fedotozine response was affected by perivagal capsaicin treatment. It was concluded that the PI-induced ileus depends on central CRF receptors. This result is consistent with the activation of an extrinsic inhibitory reflex. The reversal by kappa agonists of PI- but not CRF-induced ileus suggests that kappa agonists do not act after but before the CRF receptors. A possible peripheral action on nonvagal sensory afferents is suggested.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗
PubMed1993

Effects of a new sigma ligand, JO 1784, on cysteamine ulcers and duodenal alkaline secretion in rats.

BACKGROUND: The ulceroprotective effects of JO 1784 [(+)-N-cyclopropyl-methyl-N-methyl-1,4-diphenyl-1-ethyl-but-3-en-1-yl amine, hydrochloride], a new specific and highly selective sigma ligand, were examined in rats. METHODS: Different models of gastric ulcers (4-hour restraint stress, aspirin, ethanol, and taurocholate) and cysteamine-induced duodenal ulcers were used. The gastric acid secretion (4-hour Shay rat preparation) and the duodenal bicarbonate secretion were also studied. RESULTS: JO 1784 elicited a potent protection against duodenal ulcers but had a weaker protective effect on any of the gastric ulceration models tested. It displayed no gastric antisecretory activity but induced a dose-dependent stimulation of duodenal bicarbonate secretion. Haloperidol, hexamethonium, tetrodotoxin, bivagotomy (but not atropine), and the intravenous but not intracerebroventricular administration of devazepide, a cholecystokinin A antagonist, inhibited the stimulatory effect of JO 1784. CONCLUSION: These results show that JO 1784, a selective sigma ligand, is a potent protector of the duodenal mucosa. This activity may be related to its stimulating effect on bicarbonate secretion, which is driven through a complex nervous mechanism involving muscarinic synapses, vagal afferent fibers, and peripheral cholecystokinin receptors. This drug might open a new specific way in the treatment of duodenal ulcers.

Animals↗
PubMed1993

Fedotozine reverses ileus induced by surgery or peritonitis: action at peripheral kappa-opioid receptors.

BACKGROUND: Fedotozine is a peripheral opioid agonist. Its effects were assessed in experimental ileus in rats. METHODS: Ileus was induced by abdominal surgery (laparotomy and cecum palpation) or peritonitis (acetic acid, intraperitoneally). Digestive motility was recorded by electromyography and gastrointestinal transit estimated using a 51Cr-labeled test meal. RESULTS: Surgery or peritonitis inhibited motility and migrating myoelectrical complexes for 2-3 hours. In both models, fedotozine (3 mg/kg, intravenously; 10 mg/kg, subcutaneously) restored a normal motility pattern. This action was reproduced by the kappa-agonist, U-50, and 488H and was blocked by subcutaneous naloxone, naloxone-methiodide, or nor-binaltorphimine, a selective kappa-antagonist. Peritonitis induced a 57% inhibition of gastric emptying and intestinal transit that was reversed by fedotozine (1-10 mg/kg, subcutaneously) or kappa-agonists (U-50, 488H, bremazocine) but not delta-agonists (DPDPE, [D-Ala2]-deltorphin-II), whereas mu-agonists (morphine, fentanyl) potentiated ileus. Fedotozine restoration of transit was blocked by subcutaneous naloxone, naloxone-methiodide, or norbinaltorphimine but not by intracerebroventricular naloxone. Fedotozine was inactive up to 300 micrograms/rat when given intracerebroventrically or intrathecally. CONCLUSION: Fedotozine reverses experimental ileus via an action at peripheral kappa-opioid receptors.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗
PubMed1993

[Aspergillosis of the sphenoid sinus. Apropos of 4 cases].

Aspergillosis of the sphenoid sinus is a rare entity. The authors report four cases of non invasive aspergillosis sinusitis, three isolated cases and one with nasal polyps. All cases were treated by functional endoscopic surgery. Good results were noted with a mean follow-up of 18 months. Frequency, clinical features, treatment, and etiopathogenesis of sphenoidal aspergillosis are discussed.

Aged↗