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61.
62.
Linda Wittkop Daniel Commenges Isabelle Pellegrin Dominique Breilh Didier Neau Denis Lacoste Jean-Luc Pellegrin Geneviève Chêne François Dabis Rodolphe Thiébaut 《BMC medical research methodology》2008,8(1):68
Background
Principal component analysis (PCA) and partial least square (PLS) regression may be useful to summarize the HIV genotypic information. Without pre-selection each mutation presented in at least one patient is considered with a different weight. We compared these two strategies with the construction of a usual genotypic score. 相似文献63.
Anne Marie-Cardine Isabelle Maridonneau-Parini Siegmund Fischer 《European journal of immunology》1994,24(6):1255-1261
Relationships between CD45 and p56Ick have been suggested by co-immunoprecipitation of both proteins and by dephosphorylation of the p56lck regulatory site, Tyr 505, by CD45 in vitro. We investigated whether the kinase activity of p56lck is modulated in T cells triggered via CD45. We showed that incubation of Jurkat cells with a combination of two anti-CD45 monoclonal antibodies (mAb) (MC5/2 + D3/9) induced an increase in p56lck kinase activity, while a single mAb did not. Under these conditions, p56lck underwent two consecutive waves of activation. This was accompanied by internalization of the kinase and by a time-dependent increased accessibility of CD45 phosphatase at the plasma membrane. Similarly, activation and internalization of p56lck were observed using a combination of anti-CD45 (MC5/2) and anti-CD2(T112) mAb, suggesting that a functional complex consisting of CD45, CD2 and p56lck was formed upon cell triggering. Taken together, these results suggests that: (i) CD45 participates in the regulation of p56lck kinase activity in vivo and that (ii) CD45 could play a mediator role in the stimulation and endocytosis of p56lck through the CD2 pathway. 相似文献
64.
A PCR assay targeting the tpi gene was developed to detect and to genotype Giardia lamblia in human feces. Our assay was specific and discriminated between G. lamblia assemblages A and B. G. lamblia cysts isolated from human feces were also analyzed with two previously described PCR-restriction fragment length polymorphism (RFLP) assays, which are based on the detection of tpi or gdh genes. These RFLP analyses distinguished groups I and II within assemblage A or groups III and IV within assemblage B. Among 26 fecal samples from patients with sporadic giardiasis diagnosed by hospital laboratories, the tpi gene was amplified from 25 (96%) with our PCR assay, whereas only 21 (81%) samples were positive when the gdh gene was targeted. Of the 25 positive samples, nine (36%) contained assemblage A and 16 (64%) contained assemblage B. Thus, RFLP analysis classified eight samples (32%) in assemblage A group II, eight (32%) in assemblage B group III, and five (20%) in assemblage B group IV. The group could not be specified for four samples. The tpi and gdh genes of G. lamblia assemblage B were amplified from 14 (93%) of 15 samples collected only from French soldiers coming back from the Ivory Coast. All of these contained assemblage B group III. The PCR method developed is sensitive, simple, and specific and shows that the tpi gene is well adapted for G. lamblia genotyping. 相似文献
65.
Mourra N de Chaisemartin C Goubin-Versini I Parc R Flejou JF 《Archives of pathology & laboratory medicine》2005,129(3):403-406
Malignant deciduoid mesothelioma, a rare phenotype of epithelioid mesothelioma, arises more commonly from the peritoneum of young women, but it is also reported in the pleura of elderly people. We report a case of malignant deciduoid mesothelioma that occurred in a 41-year-old woman after cesarean section and was initially misdiagnosed as pseudotumoral deciduosis. Microscopically, the tumor was entirely composed of deciduoid areas, and only scattered tumor cells were positive for calretinin and keratin 5/6. The patient died 14 months after the first operation. This observation confirms the poor prognosis of this entity and the importance of the differential diagnosis of pseudotumoral deciduosis. 相似文献
66.
Comparison of the QUANTIPLEX HIV-1 RNA 2.0 Assay with the AMPLICOR HIV-1 MONITOR 1.0 Assay for Quantitation of Levels of Human Immunodeficiency Virus Type 1 RNA in Plasma of Patients Receiving Stavudine-Didanosine Combination Therapy 总被引:1,自引:4,他引:1 下载免费PDF全文
Michel Segondy Jacques Izopet Isabelle Pellegrin Brigitte Montes Beatrice Dumon Christophe Pasquier Martine Peeters Herve J. A. Fleury Jacqueline Puel Jacques Reynes 《Journal of clinical microbiology》1998,36(11):3392-3395
We compared the QUANTIPLEX HIV-1 RNA 2.0 assay with the AMPLICOR HIV-1 MONITOR 1.0 assay for quantitation of human immunodeficiency virus type 1 (HIV-1) RNA in plasma in the Stadi trail, which evaluated a stavudine plus didanosine combination therapy in 52 patients. HIV-1 RNA baseline values measured with AMPLICOR HIV-1 MONITOR 1.0 were significantly higher than those measured with QUANTIPLEX HIV-1 RNA 2.0, and decreases in HIV-1 RNA levels from baseline were also found to be significantly higher when measured with the AMPLICOR HIV-1 MONITOR 1.0 assay. The frequency of HIV-1 RNA levels below the lower limit of quantitation was significantly higher with QUANTIPLEX HIV-1 RNA 2.0 than with AMPLICOR HIV-1 MONITOR 1.0. Reanalysis of these results by an ultrasensitive procedure of AMPLICOR HIV-1 MONITOR 1.0 or by a modified version of the test that included additional primers adapted for non-B HIV-1 clades yielded greater differences between the QUANTIPLEX HIV-1 RNA 2.0 assay and the AMPLICOR HIV-1 MONITOR 1.0 assay. Our results indicate that a valid comparison of the virological efficacies obtained with different antiretroviral drug regimens requires the use of the same viral load quantitation procedure; further standardization between the different HIV-1 RNA quantitation kits is therefore needed. 相似文献
67.
Philippe Hup Cline Rouveirol Isabel Brito Pierre Neuvial Philippe La Rosa Eric Viara Nicolas Stransky Gaëlle Pierron Elodie Mani Caroline Brennetot Isabelle Jannoueix Nadge Gruel Alain Aurias Olivier Delattre Franois Radvanyi Emmanuel Barillot 《European journal of medical genetics》2005,48(4):467-468
68.
Giulia Barcia Marlne Rio Zahra Assouline Coralie Zangarelli Charles-Joris Roux Pascale de Lonlay Julie Steffann Isabelle Desguerre Arnold Munnich Jean-Paul Bonnefont Nathalie Boddaert Agns Rtig Metodi D. Metodiev Benedetta Ruzzenente 《European journal of human genetics : EJHG》2021,29(3):533
Mitochondrial translation is essential for the biogenesis of the mitochondrial oxidative phosphorylation system (OXPHOS) that synthesizes the bulk of ATP for the cell. Hypomorphic and loss-of-function variants in either mitochondrial DNA or in nuclear genes that encode mitochondrial translation factors can result in impaired OXPHOS biogenesis and mitochondrial diseases with variable clinical presentations. Compound heterozygous or homozygous missense and frameshift variants in the FARS2 gene, that encodes the mitochondrial phenylalanyl-tRNA synthetase, are commonly linked to either early-onset epileptic mitochondrial encephalopathy or spastic paraplegia. Here, we expand the genetic spectrum of FARS2-linked disease with three patients carrying novel compound heterozygous variants in the FARS2 gene and presenting with spastic tetraparesis, axial hypotonia and myoclonic epilepsy in two cases.Subject terms: Metabolic disorders, Mutation 相似文献
69.
The response of NG2-expressing oligodendrocyte progenitors to demyelination in MOG-EAE and MS 总被引:11,自引:0,他引:11
Reynolds R Dawson M Papadopoulos D Polito A Di Bello IC Pham-Dinh D Levine J 《Journal of neurocytology》2002,31(6-7):523-536
Remyelination of primary demyelinated lesions is a common feature of experimental models of multiple sclerosis (MS) and is also suggested to be the normal response to demyelination during the early stages of MS itself. Many lines of evidence have shown that remyelination is preceded by the division of endogenous oligodendrocyte precursor cells (OPCs) in the lesion and its borders. It is suggested that this rapid response of OPCs to repopulate the lesion site and their subsequent differentiation into new oligodendrocytes is the key to the rapid remyelination. Antibodies to the NG2 chondroitin sulphate proteoglycan have proved exceedingly useful in following and quantitating the response of endogenous OPCs to demyelination. Here we review the literature on the response of NG2-expressing OPCs to demyelination and provide some new evidence on their response to the chronic inflammatory demyelinating environment seen in recombinant myelin oligodendrocyte glycoprotein (MOG) induced experimental allergic encephalomyelitis (EAE) in the DA rat. NG2-expressing OPCs responded to the inflammatory demyelination in this model by becoming reactive and increasing in number in a very focal manner. Evidence of NG2+OPCs in lesioned areas beginning to express the oligodendrocyte marker CNP was also seen. The response of OPCs appeared to occur following successive relapses but did not always lead to remyelination, with areas of chronic demyelination observed in the spinal cord. The presence of OPCs in the adult human CNS is clearly of vital importance for repair in multiple sclerosis (MS). As in rat tissue, the antibody labels an evenly distributed cell population present in both white and grey matter, distinct from HLA-DR+microglia. NG2+cells are sparsely distributed in the centre of chronic MS lesions. These cells apparently survive demyelination and exhibit a multi-processed or bipolar morphology in the very hypocellular environment of the lesion. 相似文献
70.
Estrogen effects on object memory and cholinergic receptors in young and old female mice. 总被引:5,自引:0,他引:5
Elvire Vaucher Isabelle Reymond Robert Najaffe Satyabrata Kar Rémi Quirion Marilyn M Miller Keith B J Franklin 《Neurobiology of aging》2002,23(1):87-95
We investigated whether object recognition memory is modulated by estrogen in young (5 month) and aged (24 month) female C57Bl/6J mice, and if cholinergic muscarinic receptors might contribute to this response. Mice that were ovariectomized, or ovariectomized plus estradiol-treated three weeks before behavioral testing or quantitative autoradiography were compared to intact mice. Memory for a previously encountered object deteriorated significantly between 3 and 6h after initial exposure, regardless of animal age. In both young and aged mice, estradiol-treated mice showed significantly greater recall than did ovariectomized mice. In both age groups, the apparent number of [(3)H]pirenzepine/M(1)-like and [(3)H]AFDX384/M(2)-like muscarinic receptor binding sites was reduced in the basal forebrain as well as its projection areas following ovariectomy, but this decrease was not alleviated by estrogen. Aging poorly affected object memory, but reduced muscarinic binding in some cortical subregions and in the caudate nucleus. These findings suggest that estrogen effects on memory in C57Bl/6J mice are not due to changes in the number of muscarinic receptors. 相似文献