PubMed Health⌕ Search

Biomedical subjects

E Uro-Coste

Publications and source records attributed to E Uro-Coste.

At least 19 recordsLinked to original sources
PubMed2006

Time course of COX-1 and COX-2 expression during ischemia-reperfusion in rat skeletal muscle.

The aim of this study was to assess cyclooxygenase (COX)-1 and COX-2 expression in skeletal muscle after an ischemia-reperfusion (I/R). Male Sprague-Dawley rats were subjected to unilateral hindlimb ischemia for 2 h and then euthanized after 0, 1, 2, 4, 6, 10, 24, and 72 h of reperfusion. The COX protein and mRNA were assessed in control and injured gastrocnemius muscle. Muscle damage was indirectly determined by plasma creatine kinase activity and edema by weighing wet muscle. Creatine kinase activity in plasma increased as early as 1 h after reperfusion and returned to control levels by 72 h of reperfusion. Edema was observed at 6 and 10 h of reperfusion, but histological investigations showed an absence of tissular inflammatory cell infiltration. COX-1 mRNA was expressed in control muscle and was increased at 72 h of reperfusion, but the levels of associated COX-1 protein detected in control and injured gastrocnemius muscle were similar. COX-2 mRNA was not, or only slightly, detectable in control muscle and after I/R. In contrast, I/R induced major overexpression of COX-2 immunoreactivity at 6 and 10 h of reperfusion with a maximum at 10 h, whereas COX-2 protein was undetectable in control muscle. In conclusion, hindlimb I/R induced a large overexpression of COX-2 but not COX-1 protein between 6 and 10 h after injury. These results suggest a role for COX-2 enzyme in such pathophysiological conditions of the skeletal muscle.

Animals↗
PubMed2005

Detection of human cytomegalovirus genome and gene products in central nervous system tumours.

Human cytomegalovirus (HCMV) genome and related proteins have been reported in a great proportion of malignant gliomas. However, these results are unexpected since HCMV is not known as an oncogenic virus. By immunohistochemistry (with an anti-IE1 monoclonal antibody) and in situ hybridisation (with biotinylated DNA probes) on tissue microarrays and frozen sections, we investigated a French series of central nervous system (CNS) tumours, including 97 glioblastomas. In 10 cases of glioblastoma, rare astrocyte-like cells, admixed with tumour cells, stained positively for HCMV and in one case a doubtful staining of rare cells was noticed. This may indicate a reactivation of the virus under local immunosuppression but none of the cases of CNS tumours (n=132) contained HCMV genomes and/or proteins in a significant proportion of tumour cells. Our results strongly suggest that HCMV is unlikely to be implicated in the development of human malignant gliomas, at least in French cases.

Adult↗
PubMed2005

Immunodetection of SV40 large T antigen in human central nervous system tumours.

BACKGROUND/AIMS: DNA sequences from Simian virus 40 (SV40) have been previously isolated from various human tumours of the central nervous system (CNS). This study aimed to investigate a series of tumours of the CNS for the expression of the SV40 large T antigen (Tag), which is an oncogenic protein of the virus. METHODS: A French series of 82 CNS tumours was investigated for Tag expression using a monoclonal antibody and immunohistochemistry. A Tag positive hepatocellular carcinoma cell line from transgenic mice and a kidney biopsy from a patient infected by SV40 were used as positive controls. RESULTS: None of the tumours (20 ependymomas, 20 glioblastomas, 12 oligodendrogliomas, three plexus choroid adenomas, two plexus choroid carcinomas, 15 meningiomas, and 10 medulloblastomas) contained SV40 Tag positive cells. CONCLUSIONS: The lack of SV40 Tag in 82 CNS tumours of various types is at variance with previous studies from different countries, and suggests that the virus may not be an important factor in CNS tumorigenesis, at least in French cases.

Adolescent↗
PubMed2004

Intracellular ferritin accumulation in neural and extraneural tissue characterizes a neurodegenerative disease associated with a mutation in the ferritin light polypeptide gene.

Abnormal accumulation of ferritin was found to be associated with an autosomal dominant slowly progressing neurodegenerative disease clinically characterized by tremor, cerebellar ataxia, parkinsonism and pyramidal signs, behavioral disturbances, and cognitive decline. These symptoms may appear sequentially over a period of 4 decades. Pathologically, intranuclear and intracytoplasmic bodies were found in glia and subsets of neurons in the central nervous system as well as in extraneural tissue. Biochemical analyses of these bodies isolated from the striatum and cerebellar cortex revealed that ferritin light polypeptide (FTL) and ferritin heavy polypeptide (FTH1) were the main constituents. Molecular genetic studies revealed a 2-bp insertion mutation in exon 4 of the FTL gene. The resulting mutant polypeptide is predicted to have a carboxy terminus that is altered in amino-acid sequence and length. In tissue sections, the bodies were immunolabeled by anti-ferritin and anti-ubiquitin antibodies and were stained by Perls' method for ferric iron. Synthetic peptides homologous to the altered and wild-type carboxy termini were used to raise polyclonal antibodies. These novel antibodies as well as an antibody recognizing FTH1 immunolabeled the bodies. This study of this disorder has provided additional knowledge and insights in the growing area of ferritin-related neurodegeneration.

Adult↗
PubMed2003

[Rhino-cerebral fungal infection successfully treated with supplementary hyperbaric oxygen therapy].

Rhino-cerebral fungal infections are rare and difficult disorders to cure. We report the case of a woman presenting a left trigeminal neuralgia complicated by ophthalmoplegia and blindness. MRI demonstrated a lesion of the left orbital apex with extension into the cavernous sinus. Fungal infiltration (aspergillosis or mucormycosis), was seen on biopsy. High-dose liposomal Amphotericin B (5mg/kg/day) for six weeks was unsuccessful. Adjunctant hyperbaric oxygen therapy led to clinical and radiological improvement. Hyperbaric oxygen therapy is discussed in the medical management of rhino-cerebral yeast abscesses.

Brain Abscess↗
PubMed2002

[Value of interventional video-endoscopy in the assessment of cancer of the upper airways and digestive system].

INTRODUCTION: The aim of our study was to evaluate the video fiberoscope with operator canal (FOC) in he diagnosis of head and neck carcinoma compared to direct laryngoscopy (DL). METHODOLOGY: From August 2000 to May 2001, 82 patients were included in a prospective study. They were examined for pharyngolaryngeal cancer with the FOC, DL and a CAT-SCAN. The compared elements were the visualization of the different regions of the pharyngolarynx. A three dimensional description of the lesion, the presence of secondary localisations as well as the anatomo pathological results were obtained with FOC and DL. RESULTS: Although the pharyngolarynx is less well visualized in FOC than in DL (p = 0.04), no statistically significant difference was found between the two methods in terms of visual diagnosis and assessment of the extent of the lesion. The sensitivity of the biopsies made with FOC is lower than those performed with DL (66% FOC, 97% DL). Moreover, we have noted that FOC is highly reliant on the experience and ability of the surgeon. CONCLUSION: DL remains the most reliable technique for the exploration and diagnosis of the pharyngolarynx. If it is not possible to perform a DL or if it is not indicated (trismus, contra-indication to general anaesthesia) FOC should be considered as the examination of choice.

Adolescent↗
PubMed2001

Value of investigation in the diagnosis of allergic fungal rhinosinusitis: results of a prospective study.

The authors report a prospective study in which the aim was to analyse the usefulness of different criteria in optimizing the diagnosis of allergic fungal rhinosinusitis. From 1995 to 1998, 165 patients were operated on for chronic rhinosinusitis. Investigations used in this study for the diagnosis of allergic Aspergillus rhinosinusitis consisted of an analysis of clinical, radiological, immuno-allergic criteria. Fourteen patients presented with allergic Aspergillus rhinosinusitis. One hundred and fifty-one patients did not present any of the necessary criteria for the diagnosis of allergic Aspergillus rhinosinusitis. The results show that the characteristic macroscopic appearance, the maxillary sinus localization, and the presence of positive specific IgE to Aspergillus fumigatus are arguments that reinforce the diagnostic certitude of allergic fungal sinusitis. No specific clinical or radiological criteria orients a diagnosis of chronic rhinosinusitis toward that of allergic fungal rhinosinusitis. The other immuno-allergic tests do not contribute to the diagnosis of allergic fungal rhinosinusitis. pathological, mycological, and

Adolescent↗
PubMed2001

[Anaplastic temporal ganglioglioma with spinal metastasis].

We report the case of a 26-year-old male who was operated on after an acute episode complicating a long history of seizures. The resected temporal lesion was an anaplastic ganglioglioma. Ganglioglioma is a tumor of children and young adults, characterized by two cell components, neuronal and glial. It is usually a benign lesion. The present case is remarkable in several aspects. Hemorrhage led to the discovery of a supra-tentorial tumour. Microscopic examination revealed anaplastic foci in an otherwise typical lesion. There was a long past medical history but outcome was rapidly unfavorable after surgical resection and associated with dissemination along the spinal cord.

Adult↗
PubMed2000

Lysosomal sphingomyelinase is not solicited for apoptosis signaling.

Stress-induced activation of an acidic sphingomyelinase leading to generation of ceramide, an important lipid mediator, has been associated with apoptosis; however, the implication of this hydrolase has been questioned. The present study aimed at re-evaluating the role of this lysosomal enzyme in apoptosis initiated by different apoptotic inducers. The sensitivity of a series of acid sphingomyelinase-deficient cell lines derived from Niemann-Pick disease patients to stress-induced apoptosis was investigated. We have now shown that stress stimuli, such as anthracyclines, ionizing radiation, and Fas ligation trigger similar apoptotic hallmarks in normal and acid sphingomyelinase-deficient cell lines. Retrovirus-mediated gene correction of enzyme deficiency in Niemann-Pick cells does not modify response to apoptosis. Ceramide production is comparable in normal and Niemann-Pick cells, and increased activity of neutral sphingomyelinase is observed. Thus, our findings cast serious doubts that lysosomal sphingomyelinase activation is responsible for stress-induced apoptosis of cultured cells.

Apoptosis↗
PubMed2000

Stress-induced apoptosis is not mediated by endolysosomal ceramide.

A major lipid-signaling pathway in mammalian cells implicates the generation of ceramide from the ubiquitous sphingolipid sphingomyelin (SM). Hydrolysis of SM by a sphingomyelinase present in acidic compartments has been reported to mediate, via the production of ceramide, the apoptotic cell death triggered by stress-inducing agents. In the present study, we investigated whether the ceramide formed within or accumulated in lysosomes indeed triggers apoptosis. A series of observations strongly suggests that ceramide involved in stress-induced apoptosis is not endolysosomal: 1) Although short-chain ceramides induced apoptosis, loading cells with natural ceramide through receptor-mediated endocytosis did not result in cell death. 2) Neither TNF-alpha nor anti-CD95 induced the degradation to ceramide of a natural SM that had been first introduced selectively into acidic compartments. 3) Stimulation of SV40-transformed fibroblasts by TNF-alpha or CD40 ligand resulted in apoptosis equally well in cells derived from control individuals and from patients affected with Farber disease, having a genetic defect of acid ceramidase activity leading to lysosomal accumulation of ceramide. Also, induction of apoptosis using anti-CD95 (Fas) or anti-CD40 antibodies, TNF-alpha, daunorubicin, and ionizing radiation was similar in control and Farber disease lymphoid cells. In all cases, apoptosis was preceded by a comparable increase of intracellular ceramide levels. 4) Retroviral-mediated gene transfer and overexpression of acid ceramidase in Farber fibroblasts, which led to complete metabolic correction of the ceramide catabolic defect, did not affect the cell response to TNF-alpha and CD40 ligand.

Apoptosis↗
PubMed2000

[Neurodegenerative disease associated with a mutation of codon 279 (N279K) in exon 10 of Tau protein].

Frontotemporal dementia and Parkinsonism linked to chromosome 17 (FTDP-17) are related to pathogenic mutations of the Tau gene. One of these, located at codon 279, results in an asparagine to lysine substitution. It was detected in three unrelated families from different origins. This mutation affects splicing, allowing exon 10 to be incorporated more frequently in the Tau transcripts, causing an abnormal preponderance of three-over four-repeat isoforms in soluble tau and the presence of the four-repeat isoforms in the insoluble tau. To better understand this newly described pathology, we analysed data from the three previously reported families. The American family, described as "pallido-ponto-nigral degeneration" is a large family which has been extensively studied (13 neuropathological studies). The Japanese family was initially presented as "pallidonigroluysian degeneration with iron deposition" and recently found to be related to N279 K mutation. We reported clinical, pathological and genetic data from the French family. Clinical particularities are ocular movements alterations with vertical supranuclear palsy, extrapyramidal signs (rigidity, dyskinesia, with atypical resting and postural tremor) and progressive dementia. Partial or no L-DOPA responsiveness is noted. These features led to discuss progressive supranuclear palsy, in some cases. There is no amyotrophy, nor any sensibility to neuroleptics, both signs being observed in other FTDP-17 syndromes. Neuropathology and immunohistochemistry confirm the presence of Tau immunolabeled inclusions, affecting mainly neurons in brain stem nuclei and glial cells in supratentorial white matter. Neuronal loss, which is moderate in frontal and temporal cortex, is severe in substantia nigra and globus pallidum. It is variable in other subcortical structures. In these structures, it is associated with iron deposition. This latter may participate in the degenerative process of cells and led to death in some specific neurons. The selectivity of neuronal death in hereditary diseases, when compared to data concerning sporadic neurodegenerative diseases which share similar clinical signs and neuropathological lesions, reinforces the hypothesis of an increased vulnerability of some neuronal populations which express specific sets of tau isoforms. Neurons particularly involved in these diseases express exclusively exon 10 + tau isoforms.

Exons↗
PubMed2000

[Lysosomal disorders. Diagnostic role of extra-cerebral biopsy].

Lysosomal disorders are related to dysfunctions of lysosomes which may affect enzymes, transporters or activators. Their clinical features are varied. This is due to several mechanisms, the metabolism of nervous tissue explaining its particular involvement in sphingolipidosis. The classifications are still changing and, recently, some ceroid-lipofuscinosis were included in this group. Biological diagnosis relies on biochemical study of accumulated substrate or on enzymatic assays. It remains sometimes difficult. The analysis of tissue is then a useful tool. Biopsies from extraneural tissues, essentially skin and conjunctival biopsies, are nowadays preferred to brain biopsies. However, the location of the biopsy varies according to the suspected disease. The specimen must be adequately prepared and electron microscopy is necessary. Results of this examination are summarized. The interest of the biopsy is not restricted to diagnosis, it is useful in follow-up of treated patients and for understanding the underlying pathophysiology.

Biopsy↗
PubMed1999

[Central neurocytoma. Immunohistochemical study: MIB1, p53 and bcl-2. Report of 5 cases].

To further characterize central neurocytoma, a rare intraventricular tumour described in 1982, we analyzed six tumours by immunohistochemistry for MIB1, p53 and bcl-2. bcl-2, an inhibitor of p53-mediated apoptosis is frequently expressed in gliomas, especially in tumors with wild-type p53. Its expression in peripheral neuroblastomas suggests a down-regulation during final terminal differentiation. Six tumors from five patients (one female/four males, age ranged from 18 to 63 years) were examined. All patients were alive from 2 to 88 months after initial surgical resection. On histological sections, tumours demonstrated a typical pattern. Synaptophysin staining was seen in all cases. Proliferation index was low (< 4.5%). bcl-2 was never expressed. p53 expression varied but within low values (< 10% of cells). These latter antibodies were rarely analyzed until now in this usually benign neoplasm which represents a well differentiated variant of neuron derived tumors.

Adolescent↗
PubMed1999

[Does allergic fungal sinusitis exist? Preliminary results of a prospective study].

Allergic aspergillar sinusitis is a very controversial clinical feature. We present results of a prospective study aimed at evaluating the reality of allergic aspergillar sinusitis in a nosologic and clinical point of vue. During a 5 months period, 31 patients underwent surgery: 21 sino-nasal polyposis, 5 chronic sinusitis without polyposis, 5 chronic sinusitis with radiologic images evocative of mycosis. The study was carried out using clinical criteria (per-operative discovery of glue-like, thickened and viscous aspect of the secretions), pathologic criteria (the presence of elements consitutive of allergic mucin), mycological criteria (direct examination and culture), and immunoallergic criteria (specific IgE for Aspergillus fumigatus, serology for Aspergillus fumigatus and Aspergillus flavus (IgM, IgG), skin tests for Aspergillus fumigatus). In three cases we suspect an allergic aspergillar sinusitis (one patient presenting a bilateral chronic sinusitis and two patients presenting a sinonasal polyposis). In two patients presenting a sinonasal polyposis, a allergic fungal sinusitis was suspected, fungal identification was not possible.

Adult↗
PubMed1999

[Fatal familial insomnia].

Since its description in 1986, Fatal Familial Insomnia (FFI) became the third most common inherited prion diseases (23 described families, 3 isolated cases). It is characterized by a mutation at codon 178 of the prion protein gene cosegregating with the methionine polymorphism at codon 129 of the mutated allele. Insomnia, dysautonomia, disruption of circadian rhythms and motor dysfunctions (myoclonus, ataxia, dysarthria, spasticity) are the main clinical symptoms in the homozygote patients (met/met at codon 129). Heterozygotes have motor dysfunctions from onset and cognitive changes. Pheno-typic variability does not appear to be strictly related to codon 129 polymorphism as recently stressed in some reports. Neuropathology shows marked neuronal loss and gliosis in the thalamus, especially in the medio-dorsal and antero-ventral nuclei, without any amyloïd deposits. Some spongiosis may be seen essentially in the cerebral cortex, in patients with longer duration disease. The D178N mutation coupled with the 129 valine codon is linked to a subtype of Creutzfeldt-Jakob disease. However, in these two phenotypically different diseases, two protease resistant fragments of the pathogenic PrP (PrPres) are accumulated. They differ in molecular mass. In FFI PrPres, the unglycosylated form is underrepresented. This particularity does not result from the preferential conversion of the glycosylated forms but from an inaccessibility of non glycosylated form to conversion. PrPres has been shown to be form allelic origin. Neuronal apoptosis was found to contribute to neuronal loss in FFI. Its presence correlates with neuronal loss, being invariably noticed in the thalamus and medullary nuclei. It is not correlated with PrPres accumulation. The quantity of deposits is globally low in FFI brains and rarely immunohistochemically detected. Pathogenesis of lesions and clinical signs remain to be assessed. Protein dysfunction could be hypothesized according to some clinical and experimental data as well as to the discordance between protein accumulation and programmed cell death. Neurotoxicity is also postulated. Studies on this pathology led to consider the existence of "strains" in human prion diseases. Despite remarkable advances, many issues remain unsolved in this non spongiform prion disease.

Amino Acid Substitution↗
PubMed1998

The cell cycle gene SKP1 is regulated by light in postnatal rat brain.

During the early postnatal phase of high neuronal plasticity, an altered visual input leads to great modifications of visual cortex organization [Y. Frégnac, M. Imbert, Development of neuronal selectivity in primary visual cortex of cat, Physiol. Rev., 64 (1984) 375-434; D.H. Hubel, T.N. Wiesel, S. LeVay, Plasticity of ocular dominance columns in monkey striate cortex, Philos. Trans. R. Soc. London, Ser. B, 278 (1977) 377-409.]. We used refined differential screening of an organized cDNA library to identify the genes that may participate in this plasticity. We isolated a candidate plasticity gene encoding for a 163 aa protein that is closely related to the human and yeast Skp1p, a key factor in cell cycle progression [C. Baï, K. Hofman, L. Ma, M. Goebl, J.W. Harper, S.J. Elledge, SKP1 connects cell cycle regulators to the ubiquitin proteolysis machinery through a novel motif, the F-box, Cell, 86 (1996) 263-274; C. Connelly, P. Hieter, Budding yeast SKP1 encodes an evolutionary conserved kinetochore protein required for cell cycle progression, Cell, 86 (1996) 275-285; H. Zhang, R. Kobayashi, K. Galaktionov, D. Beach, p19Skp1 and p45Skp2 are essential elements of the cyclin A-CDK2 S phase kinase, Cell, 82 (1995) 915-925.]. Northern blot analysis showed that the expression of SKP1 (Skp1p gene) dramatically decreased after 2 h of light stimulation in the visual cortex of young dark-reared rats. This down regulation lasted at least 72 h. It was specific for the critical period as we did not observe any significant regulation of SKP1 mRNA by light in adult dark-reared rat brain. The down regulation was observed in the superior colliculus but also in the frontal cortex and in the hippocampus. The fact that this down regulation was not restricted to the visual system, suggested that it could be produced by dark rearing-induced hormonal changes. The significance of SKP1 expression in the brain and its regulation are discussed.

Animals↗