Biomedical subjects
Publications and source records attributed to D Denis.
To elucidate risk factors for congenital esotropia, this review reports on articles written on congenital esotropia during the past few years. The authors distinguish the significant risk factors of esotropia such as heredity, prematurity, perinatal difficulties, and minor risk factors such as ametropia, primary monofixation, and environmental factors.
Children's refraction and its progression are important because refractive errors can be precisely corrected. Some types of simple ametropia can generate reversible perturbations after optical correction and others are amblyogenic and strabogenic ametropia. Definition, epidemiology (frequency and risk factors), progression of refraction, evaluation and an optical correction method are described.
Potent and selective ligands for the human EP3 prostanoid receptor are described. Biaryl compounds bearing a tethered ortho substituted acidic moiety were identified as potent EP3 antagonists based on the SAR described herein. The binding affinity of key compounds on all eight human prostanoid receptors is reported.
The authors report a case of a 61-year-old man presenting bilateral exophthalmos and diabetes insipidus. A retro-orbital biopsy revealed nonspecific fibrocollagenic infiltration. The diagnosis of Erdheim-Chester disease was evoked when a multivisceral affection (retroperitoneal and mediastinal periaortic fibrosis) with specific bone localization became evident. The histopatholgical study of a bone biopsy showed xanthogranulomatous infiltration. The patient died a few months later of an intercurrent infection.
The authors report a case of de novo duplication 1q32-qter present in a patient with dysmorphic syndrome and developmental delay. This article describes the eighth case of partial trisomy 1q32-qter "pure", without chromosomal abnormalities. In the literature, a dysmorphic "syndrome" is described for trisomy 1q32-qter: hypertelorism, low set and malformed ears, prominent forehead, long philtrum, antimongoloid slanting, foot and digital malformations, cardiovascular abnormalities, urogenital abnormalities, and mental retardation. The ocular defects described in previously reported cases include: cataract, strabismus, hypoplasia of the optic disk, microphthalmia, epicanthal folds, ptosis, persistent tunica vasculosa lentis, and hyaloid vessels, but this seems to be nonspecific of this chromosomal abnormality.
PURPOSE: The aim of this work was to establish a clinical diagnostic flow chart for third nerve palsy. MATERIAL AND METHODS: [corrected] We report a series of 18 patients with third nerve palsy seen at the department of ophthalmology in the Marseille North Hospital between 1997 and 1999. All patients had a complete clinical examination and were classified into four clinic types. An etiological diagnosis was given in all cases after a systematic approach, including first intention MRI. RESULT: Three patients presented abnormal pupil reflex secondary to an aneurysm diagnosed by carotid angiography; the MRI was pathological in two cases. The 15 other patients had pupil sparing. Among them, eight patients had a total external involvement secondary to diabetes mellitus; the MRI suggested an ischelic origin in four cases (50%) showing nuclear infarctus. In seven cases the external involvement was incomplete secondary to multiple etiologies: demyelinating illness, traumatic lesions, orbital tumor, metastasis or myasthenia gravis. The MRI contributed to diagnosing four cases. CONCLUSION: The MRI must be systematically used in all the patients with isolated third nerve palsy, except for patients with pupil sparing associated with total external involvement. Ischemic etiology was the rule: simple clinical surveillance is proposed, total spontaneous regression being the norm.
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Potent and selective EP3 receptor ligands were found by making a library using solid-support chemistry. These compounds can be obtained by a Suzuki coupling reaction of a solid-supported benzyl bromide using various boronic acids. The yields obtained for this reaction were in the range of 24-95% of arylmethyl cinnamic acid 1 after cleavage from the Wang resin.
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Potent and selective antagonists of the human EP3 receptor have been identified. The structure-activity relationship of the chemical series was conducted and we found several analogues displaying sub-nanomolar K(i) values at the EP3 receptor and micromolar activities at the EP1, EP2 and EP4 receptors. The effect of added human serum albumin (HSA) on the binding affinity at the EP3 receptor was also investigated.
BACKGROUND: Patients who have experienced severe caustic injury to the gastrointestinal tract are at high risk of esophageal strictures. Early endoscopy is usually recommended systematically in children after caustic ingestion to assess the severity of the initial digestive lesions. The aim of this study was to determine the predictive value of clinical symptoms and ingested-substance types as markers of severe esophagogastric lesions and to define indications for endoscopy. METHODS: Ingested-product types, clinical symptoms, endoscopic data and outcome were prospectively recorded in 85 children admitted after accidental caustic ingestion. RESULTS: Forty-eight children (57%) had no symptoms; the others presented with vomiting, hematemesis, drooling, respiratory distress, and/or oropharyngeal lesions. Endoscopy showed no or minimal lesions in 63 cases (74%). None of the children developed digestive sequelae. Severe esophagogastric lesions were present in 22 cases (26%), mostly caused by lye ingestion (14 of 22) but also by strong acids (4 of 22); 9 of the 22 children (41%) developed esophageal stenosis. Vomiting, drooling, and oropharyngeal lesions did not predict severe endoscopic lesions. Hematemesis, respiratory distress, or presence of at least three of the symptoms was associated with severe lesions (positive predictive value = 1). The absence of symptoms was always associated with no or minimal lesions (negative predictive value = 1). CONCLUSIONS: In conclusion, endoscopy is not recommended for children living in developed countries who are asymptomatic after accidental caustic ingestion.
The structure-activity relationship (SAR) of prostaglandin (PG) E(2) at the human EP(1) prostanoid receptor (designated hEP(1)) was examined via the binding and activation of this receptor by a series of 55 prostanoids and analogs. Using clonal human embryonic kidney 293 cell lines expressing recombinant hEP(1), affinity (K(i)), potency (EC(50)), and efficacy data were obtained using a radioligand competitive binding assay and an aequorin-based calcium functional assay. All compounds behaved as full agonists (90-100% of the response elicited by PGE(2)) in this assay, and the correlation between the K(i) and EC(50) values was highly significant (R(2) = 0.86). The results from the SAR analysis can be summarized as follows: 1) the existence and configuration of hydroxyl groups at the 11 and 15 positions of PGE(2) and prostanoid analog structures play a critical role in agonist activity; 2) the carboxyl group is also important for activity and modification of the carboxylic acid to various esters results in greatly reduced affinity and potency; 3) the activity of structures with moderate or weak potency can be enhanced by modification of the omega-tail; and 4) modifications to the ketone at the 9-position are better tolerated, with 9-deoxy-9-methylene-PGE(2) being the most potent agonist tested in the functional assay. The impact of other modifications on agonist potency is also discussed. The results from this study have identified, for the first time, the key structural features of PGE(2) and related prostanoids and prostanoid analogs necessary for activation of hEP(1).
Bronchopulmonary dysplasia is the most common cause of chronic pulmonary disease in premature infants. Airway inflammation appears to play a major pathogenetic role together with barotrauma and oxygen toxicity. The aim of the present study was to determine the effect of a 15-d exposure to moderate hyperoxia (FiO2, 50%) on airway reactivity and inflammatory response in neonatal and adult rats. We studied in isolated tracheal rings the 1) isometric contraction to cumulative concentrations of carbachol (10(-8) to 10(-3) M); 2) epithelial, submucosal, smooth muscle, and connective tissue surface area; and 3) distribution of inflammatory cells (mastocytes, granulocytes, macrophages) by using MAb. Reactivity to carbachol was significantly increased in the hyperoxic pups, in which a 13% increase in tracheal smooth muscle surface area was observed. Type-I mast cells and macrophages (submucosa and connective tissue) and granulocytes (connective tissue) were increased in the neonatal hyperoxic group. Hyperoxia did not influence functional, morphometric, or cellular data in adult rats. In conclusion, exposure of newborn rats to moderate hyperoxia induces airway hyperresponsiveness and histologic changes similar to those reported in bronchopulmonary dysplasia. Hyperresponsiveness may be ascribed to an increase in smooth muscle related to the release of yet undetermined mediators by inflammatory cells infiltrating the airways. Lung immaturity definitely plays a role because similar alterations are not observed in adult rats.
Stable cell lines that individually express the eight known human prostanoid receptors (EP(1), EP(2), EP(3), EP(4), DP, FP, IP and TP) have been established using human embryonic kidney (HEK) 293(EBNA) cells. These recombinant cell lines have been employed in radioligand binding assays to determine the equilibrium inhibitor constants of known prostanoid receptor ligands at these eight receptors. This has allowed, for the first time, an assessment of the affinity and selectivity of several novel compounds at the individual human prostanoid receptors. This information should facilitate interpretation of pharmacological studies that employ these ligands as tools to study human tissues and cell lines and should, therefore, result in a greater understanding of prostanoid receptor biology.
The inhibition of PGE(2) synthesis resulting from sustained NSAIDs therapy has been linked to gastrointestinal irritations and ulceration. The multiple physiological effects of PGE(2) in the gut are mediated through the activation of four receptors termed EP(1-4). The aim of the study was to determine the precise distribution of the four prostaglandin E(2) receptors in the rat stomach, small intestine, and colon. We used non-radioactive in situ hybridization techniques on paraffin-embedded tissue. Mucous cells of the stomach and goblet cells of the small intestine and colon were found to express mRNA for all four EP subtypes. A positive hybridization signal for EP(1), EP(3), and EP(4) was detected in the parietal cells of the stomach whereas the chief cells expressed low levels of EP(1) and EP(3). The EP(1) and EP(3) receptor mRNA could also be detected in the muscularis mucosa, longitudinal muscle and enteric ganglias of the stomach and small intestine. However, close examination of the enteric ganglias indicated that most of the positive labeling was localized to the glial cells, although some neurons did express EP(3). In conclusion, we have detailed the distribution of prostanoid EP receptors in the gut at the cellular level, giving new insights to the role of prostaglandins in gastrointestinal functions.
Schizencephaly is an uncommon structural disorder of cerebral cortical development, characterized by congenital clefts spanning the cerebral hemispheres from the pial surface to the lateral ventricles and lined by cortical gray matter. Either an antenatal environmental incident or a genetic origin could be responsible for this lesion which occurs between the third and fourth month of gestation. We report the clinical and cranial imaging features of 30 children, of whom 15 had unilateral and 15 had bilateral lesions. Their ages at the time of the first presentation ranged from 1 month to 10 years. They were thoroughly studied from clinical, epileptical, imaging and electroencephalographic (EEG) viewpoints. Five patients were investigated by cranial computed tomography (CT), eight by cranial magnetic resonance (MR) imaging, and 17 by both methods. The clinical features consisted of mild hemiparesis in 17 cases (57%), 12/17 were related to a unilateral phenotype (80% of all unilateral forms) and 5/17 to a bilateral phenotype. A tetraparesis was present in nine cases, all of which were due to a bilateral cleft. Bilateral forms were significantly associated with tetraparesis, whereas unilateral forms were associated with hemiparesis. Mental retardation was observed in 17 cases (57%), and was observed significantly more often in bilateral clefts (80%). When both hemispheres are involved, an absence of reorganization of the brain function between the two hemispheres leads to severe mental deficits, in addition to the cerebral anomaly itself. Eleven patients had seizures (seven from unilateral and three from bilateral forms). The degree of malformation was not related to the severity of epilepsy. Migration disorders, such as dysplasia or heterotopia, were observed in 30% of cases and are also important etiopathogenetic factors. The septum pellucidum was absent in 13 cases (43%), with septo-optical dysplasia in two cases. Corpus callosum dysgenesis was noted in 30% of cases. Four cases of mega cisterna magna were noted. Although familial cases and environmental factors have been previously reported, schizencephaly appears to be, in the majority of cases, sporadic.
The first objective of this paper is to compare the observation procedures proposed to characterize physical work. The second objective is to examine the following 3 methodological issues: reliability, observer training, and internal validity. Seventy-two papers were reviewed, 38 of which proposed a new or modified observation grid. The observation variables identified were broken down into 7 categories as follows: posture, exertion, load handled, work environment, use of feet, use of hands, and activities or tasks performed. The review revealed the variability of existing procedures. The examination of methodological issues showed that observation data can be reliable and can present an adequate internal validity. However, little information about the conditions necessary to achieve good reliability was available.
To gain insight into the role of prostanoids in human kidney function, we examined the distribution of cyclooxygenase (COX) 1 and COX-2 by immunofluorescence and immunohistochemistry in human kidneys from adults of various age groups. COX-1 was detected in the collecting ducts, thin loops of Henle and portions of the renal vasculature. COX-2 was detected in the renal vasculature, medullary interstitial cells, and the macula densa. In addition, COX-2 immunoreactivity was noted in afferent arteries and the macula densa of the renal cortex and was more evident in the kidneys of older adults.