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C Olivier

Publications and source records attributed to C Olivier.

At least 19 recordsLinked to original sources
PubMed2006

Late-onset metachromatic leukodystrophy: genotype strongly influences phenotype.

BACKGROUND: P426L and I179S are the two most frequent mutations in juvenile and adult metachromatic leukodystrophy (late-onset MLD), which, in contrast to infantile MLD, show marked phenotypic heterogeneity. OBJECTIVE: To search for genotype-phenotype correlations in late-onset MLD. METHODS: The authors reviewed the clinical course of 22 patients homozygous for mutation P426L vs 20 patients heterozygous for mutation I179S, in which the second arylsulfatase A (ASA) mutation had also been determined. RESULTS: P426L homozygotes principally presented with progressive gait disturbance caused by spastic paraparesis or cerebellar ataxia; mental disturbance was absent or insignificant at the onset of disease but became more apparent as the disease evolved. In contrast, compound heterozygotes for I179S presented with schizophrenia-like behavioral abnormalities, social dysfunction, and mental decline, but motor deficits were scarce. Reduced peripheral nerve conduction velocities and less residual ASA activity were present in P426L homozygotes vs I179S heterozygotes. CONCLUSION: The characteristic clinical differences between homozygous P426L and compound heterozygous I179S patients establish a distinct genotype-phenotype correlation in late-onset metachromatic leukodystrophy.

Adolescent↗
PubMed2005

Semicarbazide-functionalized Si(111) surfaces for the site-specific immobilization of peptides.

The covalent attachment of semicarbazide-functionalized layers to hydrogen-terminated Si(111) surfaces is reported. The surface modification, based on the photoinduced hydrosilylation of a Si(111) surface with protected semicarbazide-functionalized alkenes, was investigated by means of X-ray photoelectron spectroscopy (XPS), contact angle measurements, and atomic force microscopy (AFM). The removal of the protecting group yielded a semicarbazide-terminated monolayer which was reacted with peptides bearing a glyoxylyl group for site-specific alpha-oxo semicarbazone ligation.

Diminazene↗
PubMed2005

Compensating strategies for impaired episodic memory and time orientation in a patient with Alzheimer's disease.

A dedicated training program for teaching a patient with Alzheimer's disease to independently use an agenda is presented. This training capitalises on preserved cognitive abilities and incorporates principles from learning theories. This case study reports the effective use of a memory book for daily life activities and of a digital clock for time reorientation.

Activities of Daily Living↗
PubMed2004

[Clinical effectiveness of seven-valent pneumococcal conjugate vaccine (Prevenar) against invasive pneumococcal diseases: prospects for children in France].

A seven-valent pneumococcal polysaccharide-CRM197 carrier protein conjugate vaccine (PNC7V; Prevenar, Wyeth, Paris) targets the serotypes (belonging to serogroups 14, 6, 19, 18, 23, 9, and 4) most often responsible for invasive pneumococcal disease (IPD) among children. A randomized, controlled, double-masked study among 37,868 children in northern California (Northern California Kaiser Permanente, USA) provided a per protocol vaccine efficacy value of 97.7% against invasive pediatric IPD due to the vaccine serotypes. The PNC7V vaccine was registered by the European Agency for the Evaluation of Medicinal Products (EMEA) in October 2000; a favorable "Community Marketing Decision" under the Centralized Procedure was granted in February 2001. PNC7V was recommended for most infants by the Conseil Supérieur d'Hygiène Publique de France in March 2002, on the advice of the Comité Technique des Vaccinations, as S. pneumoniae in children less than 2 years of age is the primary cause of bacterial meningitis and of mortality associated with community-acquired bacterial infections. The theoretical coverage of the vaccine towards pneumococcal invasive disease in France is about 80%, which represents one of the best serotype coverage estimates in Europe, and vaccines serotypes account for 90% of penicillin-nonsusceptible strains. Distinctive characteristics in France in terms of epidemiology, life style, and therapeutic attitudes justify a precise follow up of the consequences of the vaccination on a national level during the coming years. Hence, surveillance programs have been established: (i) to ascertain the future impact of large-scale PNC7V vaccination on invasive pneumococcal disease incidence, (ii) to follow the evolution of carriage and ecology of the pneumococcus, and (iii) to establish an active "vaccinovigilance".

Female↗
PubMed2003

[Inflammatory pathology in urology. Standardization].

The recognition, identification and management of the many events taking place in relation to an inflammatory response has become a rapidly growing field in medicine over the last few years. In this sense, the progress made in later years in the study of the molecular and cellular mechanisms of tissue inflammatory reactions in sites such as synovial membranes, gut mucosa, vascular endothelium etc, is considered highly relevant. A number of authors conscious of such events work on the standardization of clinical models of the inflammatory responses of genitourinary organs resulting from the action of a variety of harmful events. This review is warranted by the prevalence and morbidity and mortality of inflammatory conditions, as well as the complex work of incorporating to Urology the findings from other Biomedical Sciences.

Bacterial Infections↗
PubMed2003

[Tuberculosis: diagnosis of contact persons and chemoprophylaxis in children].

Every doctor must participate in each step of tuberculosis control including BCG vaccination and focused screening, diagnosis of contact subjects. The last is mandatory in children, due to rapid ongoing illness from primary infection (PI). The two strategies of management are the search for secondary cases around a recently diagnosed contagious tuberculosis and the search for a contaminator in front of a recent PI or illness in a child. To suppress the anonymity of notification helps. The screening relies on a "stone in the water" strategy, from close to more occasional contacts. The search for contaminators (family, collectivity) relies on chest radiography (CR) and if positive, is extended to the contaminated surroundings. The search for secondary cases relies on tuberculin intra-dermal test (IDR); if positive, a CR is asked for and always performed in aged or immunodepressed persons, and children under 5 years of age. For them, a thoracic scan is easily done because of small mediastinal adenopathies undiagnosed by plain CR. Despite imperfect sensitivity and specificity, IDR is pivotal for diagnosis in children. Any PI in children has to be treated. In France, bitherapy isoniazide-rifampicine is given before 3 years of age and often up to 10 years. A duration of 6 months is common. Patent forms receive a tri or quadri-therapy for the first 2 months followed by a 4 months bitherapy. A cornerstone of success is an adequate organisation and coordination of motivated health care workers.

Adolescent↗
PubMed2003

Challenges to HIV service provision: the commonalities for nurses and social workers.

Interdisciplinary collaboration can be enhanced through an understanding of the challenges and needs associated with service provision. This study explores the experiences of 192 service providers, with additional comparisons of nurses and social workers. Service providers reported fear of contracting HIV, feeling helpless, problems getting up-to-date information, grief and inadequate referral resources. Except for many more nurses expressing worry about contracting HIV, nurses and social workers shared many of the same problems. In addition, both groups were concerned with the comprehensive health needs of people living with HIV/AIDS. Moreover, they demonstrated shared professional values such as the importance of self-awareness and professional knowledge, positive and non-judgemental attitudes, and non-discriminatory treatment of client groups. This commonality makes nurses and social workers natural allies in responding to the many challenges associated with HIV service provision. Study findings support collaboration in the areas of service delivery, policy development, advocacy and professional development.

Adolescent↗
PubMed2002

[Staphylococcal toxic syndrome, atypical presentation of Kawasaki syndrome or staphylococcal skin syndrome?].

CASE REPORT: A three-year-old girl was admitted for persistent fever, erythermatous rash with subsequent desquamation, stomatitis, cheleitis and cervical lymphadenopathy following development of a buttock abscess secondary to an insect bite. A TSS-positive Staphylococcus aureus strain was isolated from the abscess. COMMENTS: Both clinical and bacteriological features led to discuss a "toxic shock syndrome without shock", an atypical form of Kawasaki syndrome without thrombocytosis and coronary arteritis or a staphylococcal skin syndrome. An early treatment with antibiotics could have limited the toxin production explaining both symptomatology and favourable course of the disease.

Abscess↗
PubMed2001

Sequence variability in the first internal transcribed spacer region within and among Cyclospora species is consistent with polyparasitism.

Cyclospora cayetanensis is a coccidian parasite which causes severe gastroenteritis in humans. Molecular information on this newly emerging pathogen is scarce. Our objectives were to assess genetic variation within and between human-associated C. cayetanensis and baboon-associated Cyclospora papionis by examining the internal transcribed spacer (ITS) region of the ribosomal RNA operon, and to develop an efficient polymerase chain reaction- (PCR)-based method to distinguish C. cayetanensis from other closely related organisms. For these purposes, we studied C. cayetanensis ITS-1 nucleotide variability in 24 human faecal samples from five geographic locations and C. papionis ITS-1 variability in four baboon faecal samples from Tanzania. In addition, a continuous sequence encompassing ITS-1, 5.8S rDNA and ITS-2 was determined from two C. cayetanensis samples. The results indicate that C. cayetanensis and C. papionis have distinct ITS-1 sequences, but identical 5.8S rDNA sequences. ITS-1 is highly variable within and between samples, but variability does not correlate with geographic origin of the samples. Despite this variability, conserved species-specific ITS-1 sequences were identified and a single-round, C. cayetanensis-specific PCR-based assay with a sensitivity of one to ten oocysts was developed. This consistent and remarkable diversity among Cyclospora spp. ITS-1 sequences argues for polyparasitism and simultaneous transmission of multiple strains.

Animals↗
PubMed2001

[Severe cutaneous Streptococcus pyogenes infections in the child: results of a multicenter survey].

UNLABELLED: To assess pediatric cases of severe cutaneous infections due to Streptococcus pyogenes. Since the beginning of 1980, the incidence of cellulitis and necrotizing fasciitis due to S. pyogenes has increased in adults. Serotyping of obtained isolates are in most cases M1, M3 or M5 protein. PATIENTS AND METHOD: A retrospective (1990-2000) survey was carried out in pediatric hospital centers. RESULTS: Three cases of necrotizing fasciitis and 15 of cellulitis were observed. In 30% of the cases, vancella lesions were associated; in the other cases, minor wounds were the site of the infection. Bacteriologic diagnosis was made by local samples in 14 cases; blood cultures were positive in four cases. In 11 cases, initial intravenous treatment consisted of third generation cephalosporin, in six cases of penicillin M or G and in one case of fusidic acid. In the second time, penicillin M was perfused in the majority of the cases. Mean duration of intravenous antibiotics perfusion was 15 days. There were no sequelae or death in this survey. CONCLUSIONS: Despite this study had limited epidemiological characteristics, it confirms that these two infections are rare. The frequency is probably underestimated, due to the difficulty in performing a diagnosis. The major site of infection was the varicella lesion. These two infections are so similar that it is frequent to mistake one infection for the other. Nonsteroidal anti-inflammatory drugs and site of infections did not influence prognosis. The treatment of cellulitis is penicillinotherapy whereas in necrotizing fasciitis early major surgery is often correlated with the rate of survival.

Cellulitis↗
PubMed2001

[Severe Streptococcus pyogenes cutaneous infections].

Streptococcus pyogenes is the first bacteria encountered in severe cutaneous infections in children. They enclose erysipela (papillar derma concerned more than hypoderma, lymphatic involvement) and necrotising fasciitis NF (focus on fascia and muscles with extension to hypoderma and reticular derma; venous thrombosis; hypodermic and aponevrotic necrosis). A skin lesion is the entrance of infection: varicella lesions are a major factor of NF. In France, sporadic cases in children are observed. The annual incidence of S. pyogenes invasive diseases is 1/100,000 children under 5 years of age and 0.6/100,000 children under 15 years of age. In North America, resurgence has been notified during the past ten years with mortality and morbidity due to NF and toxic shock syndromes. Interaction between bacteria and host, natural reservoir, explains the physiopathology. During the past ten years, some serotypes have become more invasive and virulent. Any cutaneous lesion interrupt the dermal barrier. Bacterial wall, proteins M and adhesins permit colonisation. Four pyrogenic exotoxins are superantigens; some facilitate inflammation, tissular lesions and shock; other participate to bacterial extension. In young children, immune response is immature. Albeit causal link between non-steroids anti-inflammatory drugs and NF in varicella children was not clearly demonstrated, caution should be kept in mind. Diagnosis of erysipela is clinical: sudden appearance of an inflammatory zone, most often on legs, with high fever and pain; sometime peripheral surelevation, lymphangitis, adenopathia. Other aspects open discussion with NF. In NF are in favour, added to high fever, huge pain, erythema and oedema: rapid extension of lesions, cutaneous hypoesthesia appearance, gap between intense severe general status (toxic shock syndrome) and paucity of local signs. NF is a medico-surgical emergency. Early surgery with complete excision of necrotic tissues permit survival. Magnetic resonance is useful in subacute NF. Microbiological diagnosis is possible in 20 to 80% of cases, using combined methods. Blood cultures identify the bacteria in 5 to 20%, skin lesion samples in 30%. Local samples are less useful even with modern techniques. Therapeutic strategy depends on initial diagnosis. Intra-venous antibiotics are necessary: penicillin (G, A or M) is first line therapy. In erysipela, ten days allow a rapid cure without sequellae. In NF, antibiotics are associated with intensive care and surgery. A late diagnosis, a too late surgery explain 16 to 36% of deaths encountered.

Adolescent↗
PubMed2001

The early steps of oligodendrogenesis: insights from the study of the plp lineage in the brain of chicks and rodents.

Oligodendrocytes are the myelin-forming cells of the central nervous system. Over the last decade, their development in the embryonic brain and spinal cord has been documented following the discovery of early oligodendroglial markers. These early expressed oligodendroglial genes nevertheless show differences in their spatiotemporal pattern of expression and it is not yet clear if their expression is linked in a linear way. This review highlights the common themes underlying the spatiotemporal aspects of oligodendrogenesis in chick and rodent brain and discusses some recent advances in the knowledge of the cell lineage expressing plp, one of the early oligodendroglial genes. We suggest a model of oligodendroglial commitment whereby definitive oligodendroglial progenitor formation is preceded by a primitive neuroglial progenitor stage and whereby different oligodendrocyte lineages might segregate from either plp-positive or plp-negative primitive progenitor cells.

Animals↗
PubMed2001

Monofocal origin of telencephalic oligodendrocytes in the anterior entopeduncular area of the chick embryo.

Oligodendrocytes are the myelin-forming cells in the central nervous system. In the brain, oligodendrocyte precursors arise in multiple restricted foci, distributed along the caudorostral axis of the ventricular neuroepithelium. In chick embryonic hind-, mid- and caudal forebrain, oligodendrocytes have a basoventral origin, while in the rostral fore-brain oligodendrocytes emerge from alar territories (Perez Villegas, E. M., Olivier, C., Spassky, N., Poncet, C., Cochard, P., Zalc, B., Thomas, J. L. and Martinez, S. (1999) Dev. Biol. 216, 98-113). To investigate the respective territories colonized by oligodendrocyte progenitor cells that originate from either the basoventral or alar foci, we have created a series of quail-chick chimeras. Homotopic chimeras demonstrate clearly that, during embryonic development, oligodendrocyte progenitors that emerge from the alar anterior entopeduncular area migrate tangentially to invade the entire telencephalon, whereas those from the basal rhombomeric foci show a restricted rostrocaudal distribution and colonize only their rhombomere of origin. Heterotopic chimeras indicate that differences in the migratory properties of oligodendroglial cells do not depend on their basoventral or alar ventricular origin. Irrespective of their origin (basal or alar), oligodendrocytes migrate only short distances in the hindbrain and long distances in the prosencephalon. Furthermore, we provide evidence that, in the developing chick brain, all telencephalic oligodendrocytes originate from the anterior entopeduncular area and that the prominent role of anterior entopeduncular area in telencephalic oligodendrogenesis is conserved between birds and mammals.

Animals↗
PubMed2001

Sonic hedgehog-dependent emergence of oligodendrocytes in the telencephalon: evidence for a source of oligodendrocytes in the olfactory bulb that is independent of PDGFRalpha signaling.

Most studies on the origin of oligodendrocyte lineage have been performed in the spinal cord. By contrast, molecular mechanisms that regulate the appearance of the oligodendroglial lineage in the brain have not yet attracted much attention. We provide evidence for three distinct sources of oligodendrocytes in the mouse telencephalon. In addition to two subpallial ventricular foci, the anterior entopeduncular area and the medial ganglionic eminence, the rostral telencephalon also gives rise to oligodendrocytes. We show that oligodendrocytes in the olfactory bulb are generated within the rostral pallium from ventricular progenitors characterized by the expression of PLP: We provide evidence that these Plp oligodendrocyte progenitors do not depend on signal transduction mediated by platelet-derived growth factor receptors (PDGFRs), and therefore propose that they belong to a different lineage than the PDGFRalpha-expressing progenitors. Moreover, induction of oligodendrocytes in the telencephalon is dependent on sonic hedgehog signaling, as in the spinal cord. In all these telencephalic ventricular territories, oligodendrocyte progenitors were detected at about the same developmental stage as in the spinal cord. However, both in vivo and in vitro, the differentiation into O4-positive pre-oligodendrocytes was postponed by 4-5 days in the telencephalon in comparison with the spinal cord. This delay between determination and differentiation appears to be intrinsic to telencephalic oligodendrocytes, as it was not shortened by diffusible or cell-cell contact factors present in the spinal cord.

Animals↗