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31.
David G Biron Cécile Joly Laurent Marché Nathalie Galéotti Vincent Calcagno Andreas Schmidt-Rhaesa Lionnel Renault Frédéric Thomas 《Infection, genetics and evolution》2005,5(2):167-175
The proteome of most parasite species is currently unknown. Hairworms (Nematomorpha), 300 species distributed around the world, are parasitic in arthropods (mainly terrestrial species) when juveniles, but they are free-living in aquatic environments when adult. Most aspects of their systematics and biology are currently unknown. The aim of this paper was (i) to report a novel and reproducible protocol for the analysis of the proteome of hairworms using two-dimensional gel electrophoresis (2-DGE) and mass spectrometry (matrix laser desorption ionization-time of flight mass spectrometry (MALDI-TOF)) and (ii) to determine the level of proteomic divergence between two sympatric but taxonomically unrelated nematomorph species in the adult stage, Paragordius tricuspidatus Dufour (Nematomorpha, Gordiidae) and Spinochordodes tellinii Camerano (Nematomorpha, Gordiidae). In total, 689 protein spots were observed for P. tricuspidatus, 575 for S. tellinii. Only 36.2% spots were shared between the two species. Quantitative analysis of the proteins which are common to both parasite species reveals substantial differences in the pattern of protein expression. These results suggest a rapid evolutionary divergence between these two nematomorph families. Also, to test the value of our MALDI-TOF protocol, we used Actin-2 (Act-2), a protein highly conserved in the course of evolution. Peptide mass fingerprint (PMF) data obtained for Act-2 of P. tricuspidatus and S. tellinii suggest a very high homology with Act-2 of different worms species belonging to the Bilateria phylum (Annelida and Nematoda) and more specifically to Lumbricus terrestris (Annelida, Lumbricidae) and Caenorhabditis elegans (Nematoda, Rhabditidae). We discuss our results in relationship with current ideas concerning the use of proteomics in systematics. 相似文献
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B Croisile B Laurent D Michel D Le Bars L Cinotti F Mauguière 《Revue neurologique》1991,147(3):192-199
The authors report 3 cases of slowly progressive aphasia with different language disturbances: anomia, pure word deafness and Broca's aphasia. All patients were independent in daily life activities. Insight, judgement and overall behaviour were intact. There was no major disturbance of other cognitive functions, but psychometric tests showed mild deficits suggesting widespread involvement. CT scans and magnetic resonance imaging showed focal dilatation of the left sylvian fissure. A positron emission tomographic study showed left perisylvian hypometabolism. A review of the literature yielded an increasing number of cases of this degenerative syndrome affecting dominant hemisphere language areas. Our cases confirm the clinical heterogeneity of degenerative aphasia. Postmortem neuropathological examinations are rare and many causes are found: Pick's disease, Alzheimer's disease or aspecific gliosis. 相似文献
35.
Laurent Garel Josée Dubois Fran?oise Rypens Alain Ouimet Salam Yazbeck 《Journal l'Association canadienne des radiologistes》2004,55(1):39-44
OBJECTIVE: To report on the high incidence of anatomical variants of the origin and course of the internal spermatic vein (ISV) discovered at the time of percutaneous embolization of left varicoceles in a pediatric population. METHODS: We reviewed retrospectively the 65 cases of left varicocele treated by percutaneous embolization (grade II and III) in our institution between 1990 and 2000. The course of the left renal vein (LRV), the origin of the ISV, and the number of ISVs and their pathway were recorded in all cases, according to the B?hren classification. RESULTS: In 37/65 (57%), the ISV was single and arose from a normal LRV (type I). The following variants were encountered: type V--circumaortic LRV 9/65 (14%); type IVb--intrarenal origin of ISV 8/65 (12%); type II--multiple ISV 5/65 (8%); and pelvic collaterals 6/65 (9%). CONCLUSION: Venous anatomical variants are frequently encountered (43%) at the time of left varicocele embolization in children. Such variants often impose some adjustments to the technique of embolization and, at times, hamper the procedure. 相似文献
36.
Hongbo Wang Songyun Li Laurent Givalois & Georges Pelletier 《Journal of neuroendocrinology》1998,10(3):193-198
Recently, an 86-amino acid polypeptide with high affinity for diazepam binding sites, termed diazepam-binding inhibitor (DBI), has been found in the rat brain. DBI, as well as a peptide derived from DBI, the octadecaneuropeptide DBI[33–50] (ODN), interacts with the GABAA receptor complex. To investigate the role of these endogenous ligands for GABAA receptors on prolactin gene expression, we studied the effects of acute intracerebroventricular administration (4 h before sacrifice) of ODN on prolactin mRNA levels in the male rat. Because, in some neuropeptidergic systems, glucocorticoids play a role in the response to ODN, we also studied the influence of adrenal glands and the effect of dexamethasone administration in the response of prolactin gene expression to ODN. ODN injection produced an increase in prolactin mRNA levels. Adrenalectomy performed 5 days before sacrifice resulted in an increase in prolactin gene expression and also potentiated the stimulating effect of ODN. Because castration has been shown to decrease prolactin gene expression in the male rat, we used castrated and adrenalectomized animals to study the role of dexamethasone in the response of lactotrophs to ODN. In these steroid-deprived animals, dexamethasone treatment (for 4 days) decreased prolactin mRNA levels but did not modify the response to ODN. These data indicate that an endogenous neuropeptide interacting with the GABAA receptor complex can stimulate prolactin gene expression and suggest that the adrenal glands may produce factor(s) capable of decreasing prolactin mRNA. On the other hand, it does not appear that glucocorticoid hormones play a role in the effect of ODN on lactotroph activity. 相似文献
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Polymorphisms in DNA repair genes as risk factors for spina bifida and orofacial clefts 总被引:2,自引:0,他引:2
Olshan AF Shaw GM Millikan RC Laurent C Finnell RH 《American journal of medical genetics. Part A》2005,135(3):268-273
Repairing DNA damage is critical during embryogenesis because development involves sensitive periods of cell proliferation, and abnormal cell growth or death can result in malformations. Knockout mouse experiments have demonstrated that disruption of DNA repair genes results in embryolethality and structural defects. Studies using mid-organogenesis rat embryos showed that DNA repair genes were variably expressed. It is hypothesized that polymorphisms that alter the functionality of DNA repair enzymes may modify the risk of malformations. We conducted a case-control analysis to investigate the relationship between DNA repair gene polymorphisms and the risk of spina bifida and oral clefts. Newborn screening blood spot DNA was obtained for 250 cases (125 spina bifida, 125 oral clefts) identified by the California Birth Defects Monitoring Program, and 350 non-malformation controls identified from birth records. Six single nucleotide polymorphisms of five DNA repair genes representing three distinct repair pathways were interrogated including: XRCC1 (Arg399Gln), APE1 (Asp148Glu), XRCC3 (Thr241Met), hOGG1(Ser326Cys), XPD (Asp312Asn, Lys751Gln). Elevated or decreased odds ratios (OR, adjusted for race/ethnicity) for spina bifida were found for genotypes containing at least one copy of the variant allele for XPD [751Gln, OR = 1.62; 95% confidence interval (CI) = 1.05-2.50] and APE 148 (OR = 0.58; CI = 0.37-0.90). A decreased risk of oral clefts was found for XRCC3 (OR = 0.62; CI = 0.39-0.99) and hOGG1 (326 Cys/Cys, OR = 0.22; CI = 0.06-0.78). This study suggested that polymorphisms of DNA repair genes, representing different major repair pathways, may affect risk of two major birth defects. Future, larger studies, examining additional repair genes, birth defects, and interaction with exposures are recommended. 相似文献
39.
The atheroprotective effect of 17beta-estradiol depends on complex interactions in adaptive immunity
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Elhage R Gourdy P Jawien J Brouchet L Castano C Fievet C Hansson GK Arnal JF Bayard F 《The American journal of pathology》2005,167(1):267-274
Estradiol prevents fatty streak formation in chow-fed atherosclerosis-prone apolipoprotein E (ApoE)-deficient mice. We previously reported that fatty streak development of immunodeficient ApoE(-/-)/recombination activating gene 2 (RAG-2(-/-)) double-deficient mice was insensitive to estradiol. In the present work, we demonstrate that the reconstitution of ApoE(-/-)/RAG-2(-/-) with bone marrow from immunocompetent ApoE(-/-)/RAG-2(+/+) mice restores the protective effect of estradiol on fatty streak constitution. We extended this demonstration to the model of low-density lipoprotein receptor-deficient mice, establishing the obligatory role of mature lymphocytes in this process. We then investigated whether the protective effect of estradiol was mediated by a specific lymphocyte subpopulation by studying the hormonal effect on fatty streak constitution in recently developed models of ApoE(-/-) mice deficient in selective T-lymphocyte subsets (either TCRalphabeta+, CD4+, CD8+, or TCRgammadelta+ lymphocytes) or B lymphocytes. In all these specifically immunodeficient mice, estradiol administration to ovariectomized mice conferred protection as in immunocompetent ApoE(-/-) mice, clearly demonstrating that no single lymphocyte subpopulation was specifically required for this effect. These results point to additional lymphocyte-dependent mechanisms such as modulating the interactions among lymphocytes and between lymphocytes and endothelial and/or antigen-presenting cells. 相似文献
40.
Voluntary HIV counseling and testing: experience among the sexually active population in Bangui,Central African Republic 总被引:4,自引:0,他引:4
Grésenguet G Séhonou J Bassirou B Longo Jde D Malkin JE Brogan T Bélec L 《Journal of acquired immune deficiency syndromes (1999)》2002,31(1):106-114
OBJECTIVES: In July 1997, the National Reference Center for Sexually Transmitted Diseases of Bangui, Central African Republic (CAR), was expanded by the creation of an anonymous and voluntary counseling and testing (VCT) unit for HIV infection, the Anonymous Surveillance Unit (Unité de Dépistage Anonyme [UDA]). The goal of the UDA was to initiate and promote voluntary HIV testing in the general adult population of Bangui. We carried out an observational and comprehensive survey over a 4-year period to document and analyze the experience of VCT in the UDA, with special attention to risk factors associated with HIV infection. METHODS: All clients for VCT were given adequate pretest counseling by trained counselors focused on knowledge about HIV infection and sexually transmitted infections, individual risks of acquiring HIV, and anticipation of the client's attitude about test results. After consent was obtained, a blood sample was drawn and tested for HIV by two ELISAs in parallel. The client paid a standard cost of $1.20 at the initial visit. After a week, test results were given to the client during the posttest visit, at which time HIV-seropositive individuals received emotional support and were referred to specific social or medical structures. Seronegative clients received reinforcement of prevention messages and were asked to come back for serologic follow-up free of charge after 3 (M3) and 12 (M12) months. RESULTS: From July 1997 to March 2001, 5686 individuals aged 14 to 65 years (mean age, 27 years) had an initial visit for VCT (V1). Peaks of UDA visitation (250-450 clients) were observed on the annual AIDS Day in the CAR, at which time HIV serologic testing was offered free of charge. A total of 5060 (89%) clients came back for a second visit (V2) to receive test results. Among those, 18.3% were infected with HIV type 1. Multivariate analysis of risk factors demonstrated marked association of HIV seropositivity with age, female gender, widowed/divorced women, poor or low education level, occupations such as civil servants or merchants, presence of symptoms of sexually transmitted infections, and lack of systematic condom use. Single young women were at higher risk for HIV infection compared with men of the same age (OR = 7.7 for women aged 15-24 years, 95% CI: 4.0-14.0; OR = 2.8 for women aged 25-34 years, 95% CI: 1.7-4.5). Widowed women older than 44 years of age were more likely to be HIV-seropositive than men (OR = 10.0; 95% CI: 1.7-83.6). A total of 885 (21%) HIV-seronegative individuals returned for follow-up at 3 months (M3; 0.45% rate of seroconversion). Seventy-nine (9%) individuals returned at 12 months (M12), without any new cases of HIV infection. HIV-negative clients consulting at M3 and M12 showed a significant reduction in unprotected intercourse with occasional sexual partners. CONCLUSION: This experience demonstrates that VCT for HIV infection is feasible in Central Africa. 相似文献