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41.
Illigens BM Yamada A Fedoseyeva EV Anosova N Boisgerault F Valujskikh A Heeger PS Sayegh MH Boehm B Benichou G 《Human immunology》2002,63(10):912-925
In this study, we measured direct and indirect T-cell alloresponses mediated by CD4(+) and CD8(+) T cells in three mouse transplantation models: skin, cornea, and retina. We show that the contribution of direct and indirect antigen recognition pathways to the alloresponse to fully allogeneic grafts varies depending upon the nature of the tissue/organ transplanted. The implications of this finding for understanding the cellular mechanisms by which rejection is mediated in different transplant models are discussed. 相似文献
42.
Colombet I Aguirre-Junco AR Zunino S Jaulent MC Leneveut L Chatellier G 《International journal of medical informatics》2005,74(7-8):597-604
Despite initiatives to standardize methods for the development of clinical guidelines, several barriers hinder their integration in daily clinical practice: failure to fulfil quality criteria, poor effectiveness of their dissemination. Computerization of guidelines can favor their dissemination. The initial step of computerization is the knowledge specification from the text of the guideline. We describe the method of knowledge specification, which is used in EsPeR (Personalized Estimate of Risks), a web-based decision support system in preventive medicine, which allows, for a given person, to estimate risks and access recommendations, based on clinical profile. This method is based on a structured and systematic analysis of text allowing detailed specification of a decision tree. We use decision tables to validate the decision algorithm and decision trees to specify this algorithm, along with elementary messages of recommendation. Editing tools are used to facilitate the process of validation and the workflow between expert physicians and computer scientists. Applied to eleven different guidelines, the method allows a quick and valid computerization and integration in the EsPeR system. The method used for computerization could help to define a framework usable at the initial step of guideline development in order to produce guidelines ready for electronic implementation. 相似文献
43.
TaqMan amplification system with an internal positive control for HCV RNA quantitation. 总被引:6,自引:0,他引:6
44.
Descamps D Flandre P Joly V Meiffrédy V Peytavin G Izopet J Tamalet C Zeng AF Harel M Lastère S Aboulker JP Yéni P Brun-Vézinet F;NOVAVIR 《Journal of acquired immune deficiency syndromes (1999)》2002,31(5):464-471
The authors studied the effect of zidovudine (ZDV) resistance mutation on virologic response to treatment with ZDV or stavudine (d4T) each in combination with lamivudine and indinavir. Viral genotyping was performed on plasma HIV-1 RNA at study entry and concerned 155 patients previously treated with ZDV, didanosine, or zalcitabine and enrolled in the NOVAVIR (Agence National de Recherche sur le SIDA [ANRS] 073) trial. Three virologic responses were investigated: early response (<50 copies/mL at week 24), late response (<500 copies/mL at week 80), and virologic failure (two HIV-1 RNA >5000 copies/mL). Patients were classified as resistant or susceptible to ZDV according to the ANRS algorithm. Plasma viral RNA from 123 of 155 patients had two or more ZDV resistance mutations. The number of ZDV resistance mutations was positively correlated with the duration of prior antiviral therapy (p <.001). At week 24, 74% and 77% of patients with virus classified as resistant were responders in the d4T and ZDV arm, respectively. Similar results were found at week 80. Virologic failure was reached in 7 of 24 patients with virus classified as susceptible and in 26 of 131 patients with resistant virus (p =.29). In the ZDV arm, patients classified as resistant had longer times to virologic failure than those classified as susceptible (p =.003). In conclusion, sustained virologic response despite presence of ZDV resistance mutations implies that these mutations do not preclude an early and durable response to treatment with a potent three-drug regimen in these patients. Patients susceptible to ZDV had lower median mean corpuscular volumes and lower random indinavir levels, suggesting that adherence was the main reason for failure. 相似文献
45.
Moore ST Clément G Raphan T Cohen B 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,137(3-4):323-335
During the 1998 Neurolab mission (STS-90), four astronauts were exposed to interaural centripetal accelerations (Gy centrifugation)
of 0.5g and 1g during rotation on a centrifuge, both on Earth and during orbital space flight. Subjects were oriented either left-ear out
or right-ear out, facing or back to motion. Binocular eye movements were measured in three dimensions using a video technique.
On Earth, tangential centrifugation that produces 1g of interaural linear acceleration combines with gravity to tilt the gravitoinertial acceleration (GIA) vector 45° in the
roll plane relative to the head vertical, generating a summed vector of 1.4g. Before flight, this elicited mean ocular counterrolling (OCR) of 5.7°. Due to the relative absence of gravity during flight,
there was no linear acceleration along the dorsoventral axis of the head. As a result, during in-flight centrifugation, gravitoinertial
acceleration was strictly aligned with the centripetal acceleration along the interaural axis. There was a small but significant
decrease (mean 10%) in the magnitude of OCR in space (5.1°). The magnitude of OCR during postflight 1g centrifugation was not significantly different from preflight OCR (5.9°). Findings were similar for 0.5g centrifugation, but the OCR magnitude was approximately 60% of that induced by centrifugation at 1g. OCR during pre- and postflight static tilt was not significantly different and was always less than OCR elicited by centrifugation
on Earth for an equivalent interaural linear acceleration. In contrast, there was no difference between the OCR generated
by in-flight centrifugation and by static tilt on Earth at equivalent interaural linear accelerations. These data support
the following conclusions: (1) OCR is generated predominantly in response to interaural linear acceleration; (2) the increased
OCR during centrifugation on Earth is a response to the head dorsoventral 1g linear acceleration component, which was absent in microgravity. The dorsoventral linear acceleration could have activated
either the otoliths or body-tilt receptors that responded to the larger GIA magnitude (1.4g), to generate the increased OCR during centrifugation on Earth. A striking finding was that magnitude of OCR was maintained
throughout and after flight. This is in contrast to most previous postflight OCR studies, which have generally registered
decreases in OCR. We postulate that intermittent exposure to artificial gravity, in the form of the centripetal acceleration
experienced during centrifugation, acted as a countermeasure to deconditioning of this otolith-ocular orienting reflex during
the 16-day mission.
Electronic Publication 相似文献
46.
Eric Hergon Jean-Yves Py Stéphanie Jullien Jean-Fran?ois Quaranta Gilles Folléa Georges Andreu Jean-Jacques Cabaud Pascal Staccini Philippe Rouger 《Transfusion Clinique et Biologique》2007,14(3):371-377
The evaluation of the professional practices (EPP) is obligatory for all the physicians since July 1, 2005 for a first five-year period. It represents one of the components of the continuous medical training (CMT). The French Society of Blood Transfusion and National Institute of Blood Transfusion are the promoters of the EPP in transfusion technology and medicine. Initially, the programs of EPP will be conceived and controlled by experts and will relate to their basic activities. During a five years cycle, the physician taking part in a program must validate a specific action and take part in a rolling programme. At the end of the programme, the physician will receive a certificate issued by National Institute of Blood Transfusion and will have to submit it to a committee placed under the responsibility of the regional physicians' committee. 相似文献
47.
Christine Gilles Myriam Polette Philippe Birembaut Nils Brünner Erik W Thompson 《Clinical & experimental metastasis》1997,15(5):519-526
We have previously observed in vitro that some stromal proteinases (MMP-2, MT1-MMP) were expressed or activated by invasive carcinoma cell lines exhibiting mesenchymal features, presumably acquired through an epithelial to mesenchymal transition (EMT). To examine the potential contribution of c-ets-1 to this phenotype, we have compared here the expression of c-ets-1 with invasiveness in vitro and expression of vimentin, E-cadherin, uPA, MMP-1 and MMP-3 in a panel of human breast cancer cell lines. Our results clearly demonstrate an association between c-ets-1 expression and the invasive, EMT-derived phenotype, which is typified by the expression of vimentin and the lack of E-cadherin. While absent from the two non-invasive, vimentin-negative cell lines, c-ets-1 was abundantly expressed in all the four vimentin-positive lines. However, we could not find a clear quantitative or qualitative relationship between the expression of c-ets-1 and the three proteinases known to be regulated by c-ets-1, except that when they were expressed, it was only in the invasive c-ets-1-positive lines. UPA mRNAs were found in three of the four vimentin-positive lines, MMP-1 in two of the four, and MMP-3 could not be detected in any of the cell lines. Intriguingly, MDA-MB-435 cells, which exhibit the highest metastatic potential of these cell lines in nude mice, expressed vimentin and c-ets-1, but lacked expression of these three proteinases, at least under the culture conditions employed. Taken together, our results show that c-ets-1 expression is associated with an invasive, EMT-derived phenotype in breast cancer cells, although it is apparently not sufficient to ensure the expression of uPA, MMP-1 or MMP-3, in the vimentin-positive cells. Such proteases regulation is undoubtedly qualified by the cellular context. This study therefore advances our understanding of the molecular regulation of invasiveness in EMT-associated carcinoma progression, and suggests that c-ets-1 may contribute to the invasive phenotype in carcinoma cells. 相似文献
48.
Identification of iduronate sulfatase gene alterations in 70 unrelated Hunter patients 总被引:4,自引:0,他引:4
Roseline Froissart Irène Maire Gilles Millat Stéphane Cudry Anne-Marie Birot Véronique Bonnet Olivier Bouton Dominique Bozon 《Clinical genetics》1998,53(5):362-368
We studied 70 unrelated Hunter patients and found a gene alteration in every patient. The molecular heterogeneity was very important. Large gene rearrangements were identified in 14 patients. Forty-three different mutations were identified in the 56 other patients and 31 were not previously described. Deletions and insertions, splice site mutations were associated with a severe phenotype as nonsense mutations except Q531X. Only a few mutations were present in several patients making difficult genotype-phenotype correlations. Mutation identification allows accurate carrier detection improving prenatal diagnosis. The mother was not found to be a carrier in five cases among the 44 sporadic cases. Haplotype analysis demonstrated a higher frequency of mutations in male meiosis. 相似文献
49.
Equine arteritis virus (EAV) is the etiological agent of equine viral arteritis, a contagious viral disease of equids. EAV is the prototype virus of the arteriviruses, a group of small enveloped viruses with positive single-stranded RNA genomes. Because apoptosis or programmed cell death is believed to play an important role in the biogenesis of several cytopathogenic viruses, we examined whether EAV was able to induce cell apoptosis in vitro. To do this, Vero cells were infected with EAV at a multiplicity of infection of 0.1 tissue culture infectious dose (TCID50) per cell, and analyzed at various time intervals for the appearance of apoptotic signs. Fragmentation of chromosomal DNA into nucleosomal oligomers and caspase activation were observed in the infected cells at the time (e.g. 24 h postinfection) where a noticeable cytopathic effect was observed. The kinetics of the DNA fragmentation correlated with that of the production of progeny virus, so that viral multiplication was not interrupted by the apoptotic cell damage. All these data provide evidence that EAV is able to induce apoptotic cell death in vitro. 相似文献
50.
Der-Sarkissian H Vergnaud G Borde YM Thomas G Londoño-Vallejo JA 《Genome research》2002,12(11):1673-1678
The subtelomeric domains of chromosomes are probably the most rapidly evolving structures of the human genome. The highly variable distribution of large duplicated subtelomeric segments has indicated that frequent exchanges between nonhomologous chromosomes may have been taking place during recent genome evolution. We have studied the extent and variability of such duplications using in situ hybridization techniques and a set of well-defined subtelomeric cosmid probes that identify discrete regions within the subtelomeric domain. In addition to reciprocal translocation and illegitimate recombination events that could explain the observed mosaic pattern of subtelomeric regions, it is likely that homology-based recombination mechanisms have also contributed to the spread of distal subtelomeric sequences among particular groups of nonhomologous chromosome arms. The frequency and distribution of large-scale subtelomeric polymorphisms may have direct implications for the design of chromosome-specific probes that are aimed at the identification of cryptic subtelomeric deletions. Furthermore, our results indicate that the relevance of some of the telomere closures proposed within the present Human Genome Sequence draft are restricted to specific allelic variants of unknown frequencies. 相似文献