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21.
Besides the newly developed positron emission tomography scanners (microPET) dedicated to the in vivo functional study of small animals, autoradiography remains the reference technique widely used for functional brain imaging and the gold standard for the validation of in vivo results. The analysis of autoradiographic data is classically achieved in two dimensions (2D) using a section-by-section approach, is often limited to few sections and the delineation of the regions of interest to be analysed is directly performed on autoradiographic sections. In addition, such approach of analysis does not accommodate the possible anatomical shifts linked to dissymmetry associated with the sectioning process. This classic analysis is time-consuming, operator-dependent and can therefore lead to non-objective and non-reproducible results. In this paper, we have developed an automated and generic toolbox for processing of autoradiographic and corresponding histological rat brain sections based on a three-step approach, which involves: (1) an optimized digitization dealing with hundreds of autoradiographic and histological sections; (2) a robust reconstruction of the volumes based on a reliable registration method; and (3) an original 3D-geometry-based approach to analysis of anatomical and functional post-mortem data. The integration of the toolbox under a unified environment (in-house software BrainVISA, http://brainvisa.info) with a graphic interface enabled a robust and operator-independent exploitation of the overall anatomical and functional information. We illustrated the substantial qualitative and quantitative benefits obtained by applying our methodology to an activation study (rats, n=5, under unilateral visual stimulation).  相似文献   
22.
Introduction Failure to enter the coronary sinus (CS) with a guiding catheter and entering its tributaries remains challenging in left ventricle (LV) pacing lead implants for cardiac resynchronization therapy (CRT). A dual telescoping catheter system (8F outer/6F inner) is designed to provide the ability to adjust the catheter curve size, shape and/or reach to the patients’ anatomy avoiding the need for catheter change. Methods Five different designs for CS cannulation were randomly tested in 64 patients scheduled for CRT device implant. Results In 33 consecutive patients three adaptable telescoping guiding catheter systems were tested per patient, the adaptable catheters had higher overall cannulation success rates (68, 63 and 62%) compared to the fixed shape catheter (46%) and an greater cannulation success rate when the CS location was not known (70, 53 and 72% vs 33% for the fixed shape). In a second group of 31 CRT patients the two telescoping catheters had similar high levels of success (71–80%), with or without using the inner catheter. Conclusions The telescopic system is adaptable to a wide range of anatomical variations in patients and can result in a higher CS cannulation success rate due to its adjustability in the RA in search for the CS ostium. On top of this the inner catheter allows for sub-selecting the CS tributaries.  相似文献   
23.
Aims: The inversion of melatonin circadian rhythm secretionin some alcoholics during both intake and acute withdrawal hasbeen widely reported. In the same way, what happens to thisinversion when these patients are in long-term withdrawal isnot known. To document this abnormality in alcoholics afterwithdrawal we investigated melatonin secretion observed duringchronic alcoholization and after withdrawal. Methods: We measuredthe urinary 6-sulfatoxymelatonin (6SM) (6SM/creatinine ratio),main metabolite of the hormone, in two fractions, one diurnaland the other nocturnal, in seven alcohol-dependent patientspresenting with this abnormality during alcoholization at twotimes: in acute withdrawal phase (under benzodiazepines) and15 days after beginning of withdrawal (free of any psychotropictreatment). Results: Our results show that this reversed rhythmof melatonin secretion as seen by the diurnal excretion of 6SM(6SM/creatinine ratio) persists during acute withdrawal in morethan half of the patients and is still present 15 days afterwithdrawal in three patients. Conclusion: It is remarkable thatthe inversion of the melatonin rhythms gets corrected in fourout of seven patients after withdrawal. But, the circadian disorganizationof melatonin secretion in three patients could underline a desynchronizationin some alcoholic patients and may indicate more widespreadcircadian temporal structure disturbances in these patients.  相似文献   
24.
A number of cytolytic T lymphocyte (CTL) clones derived from several melanoma patients have been found to recognize a majority of melanomas from HLA-A2 patients. We have reported previously that two such CTL clones recognize a product of the tyrosinase gene that is presented by HLA-A2. Here we show that one of these CTL clones recognizes a peptide encoded by the first nine amino acids of the putative signal sequence of tyrosinase. The other CTL clone recognizes a different tyrosinase peptide corresponding to amino acids 368–376. Both peptides contain consensus motifs of HLA-A2 binding peptides.  相似文献   
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In this study, a replicative fowl adenovirus serotype 1 (CELO) recombinant expressing chicken interferon-gamma (ChIFN-gamma) was constructed. In the engineered recombinant, the ChIFN-gamma gene was placed under the control of cytomegalovirus (CMV) promoter. The ChIFN-gamma expression cassette was inserted in the right end of the CELO genome (D fragment), which was able to carry the largest insertion of foreign DNA without affecting the replication functions of the vector. The recombinant ChIFN-gamma (rChIFN-gamma) produced in the CELO-virus expression system was characterized by comparing its biologic activities with that of rChIFN-gamma produced via the baculovirus expression system (Bac-ChIFN-gamma). CELO-ChIFN-gamma inhibited the replication of cytolytic virus in chicken embryo fibroblasts (CEFs) and activated macrophages in a better manner than did Bac-ChIFN-gamma . Moreover, the in vitro and in vivo stability of the CELO-derived rChIFN-gamma was considerably higher than that of the Bac-ChIFN-gamma. The CELO-ChIFN-gamma recombinant vector was able to replicate in vitro in the loghorn male hepatoma (LMH) hepatocyte cell line and to produce detectable levels of recombinant cytokine in supernatant as early as 90 min post-infection. Therefore, the CELO-virus expression system is an appropriate system for high-level expression of biologically active and stable ChIFN-gamma.  相似文献   
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A subunit approach to the development of a respiratory syncytial virus (RSV) vaccine was investigated. It involved the production, inEscherichia coli,of an RSV (Long) G protein fragment (G2Na) as a C-terminal fusion partner to an albumin binding region (BB) of streptococcal protein G. G2Na incorporated amino acid residues 130–230 and was specifically recognized by murine anti-RSV-A polyclonal serum. In mice, intraperitoneal immunization with BBG2Na induced high anti-RSV-A serum ELISA titers and low to moderate neutralization activity. The immune response induced by BBG2Na demonstrated a potent protective efficacy against upper and lower respiratory tract RSV-A infection. The immunogenicity and protective efficacy of BBG2Na was maintained for at least 47 and 48 weeks, respectively, and was as potent and durable as live RSV-A administered in a similar fashion. Intramuscular immunization of cotton rats with BBG2Na protected lungs from both homologous and heterologous virus challenge. In contrast to mice, however, cotton rat nasal tracts were not protected after BBG2Na immunization. Consistent with antibody-mediated protection, virus was cleared within 24 hr from the lungs of BBG2Na-immunized mice. The anti-RSV-A antibodies induced in mice were exclusively of the IgG1 isotype and were detected in the serum, lungs, and nasal tracts. Passive transfer of these antibodies prevented acute, and eliminated chronic, RSV-A lung infection in normal and immunodeficient mice, respectively, confirming that such antibodies are important and sufficient for BBG2Na-induced pulmonary protection. Our results clearly demonstrate that BBG2Na contains an important immunogenic domain of the RSV G protein. The prokaryotic origin of this protein indicates that glycosylation of the RSV G protein is not necessary for protective efficacy. Thus, BBG2Na has potential as an RSV subunit vaccine.  相似文献   
30.
Summary The purpose of this study was to compare two ways of estimating both fatigue and fitness indicators from systems model of the effects of training on performance. The model was applied to data concerning the training of a hammer thrower. The variations in performance were mathematically related to the successive amounts of training. The model equation was composed of negative (NF) and positive (PF) functions. The NF and PF were associated with the fatigue and fitness estimated in previous studies. Using another method, fatigue and fitness indicators were estimated from a combination of NF and PF. The influence of training on performance was negatively associated with fatigue (NI), and positively to fitness (PI). The changes in performance were well described by the model in the present study (r = 0.96,N = 19,P<0.001). Significant correlations were observed between NF and NI (r = 0.93,P < 0.001) on the one hand and between PF and PI (r = 0.90,P < 0.001) on the other. The absolute values and the time variations of PI and NI were closer to the change in performance than NF and PF. The NF and PF were accounted for mainly by the accumulation of amounts of training. On the other hand, NI and PI were accounted for rather by the impact of these amounts of training on performance.  相似文献   
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