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排序方式: 共有542条查询结果,搜索用时 15 毫秒
71.
72.
Niu L Termini JM Kanagavelu SK Gupta S Rolland MM Kulkarni V Pavlakis GN Felber BK Mullins JI Fischl MA Stone GW 《Vaccine》2011,29(11):2110-2119
Background
Dendritic cell (DC) therapy is a promising technology for the treatment of HIV infected individuals. HIV-1 Gag- and Nef RNA-loaded DC have previously been shown to induce immune responses ex vivo following coculture with autologous lymphocytes. However, polyfunctionality and memory responses following coculture have not been evaluated. In addition, little is known regarding whether specific HIV-1 proteome components, such as highly conserved regions of the HIV-1, could enhance clinical responses following DC therapy.Methodology and principal findings
To determine the breadth of the immune responses to antigen loaded DC, we analyzed polyfunctional T cell response ex vivo to Gag RNA loaded DC. Blood samples were used to generate monocyte derived DC, which were then matured and cocultured with autologous lymphocytes. We found that cytokine-matured DC loaded with Gag RNA was able to induce Gag-specific IFN-γ and IL-2 responses after a 12-day coculture. We characterized these responses by polyfunctional intracellular cytokine staining and evaluation of T cell memory phenotypes. Central memory CD8+ T cells were induced ex vivo after DC coculture from each of 3 patients, and the effector memory pool was increased by DC coculture from 2 patients. We also observed a decrease in the terminal effector and intermediate CD8+ T cell pool and an increase in the naïve/other population. There was a reduction in terminal effector and intermediate CD4+ T cells, and a corresponding increase in naïve/other CD4+ T cells. Finally, we evaluated conserved regions of Gag as a novel DC therapy immunogen and found that a conserved element (CE) p24 Gag antigen elicited IFN-γ and IL-2 responses comparable to those induced by a full-length Gag antigen.Conclusions
We showed that RNA-loaded DC therapy induced a polyfunctional T cell response ex vivo, supporting the use of such DC-therapy for HIV infection. However, the central and effector memory phenotypes of T cells did not appear to be enhanced during coculture with Gag RNA-loaded DC. Furthermore, comparable antigen-specific responses were induced in HIV infected individuals using full-length Gag or only conserved elements of the Gag p24 protein. This indicates that immune responses can be focused onto the conserved elements of Gag in the absence of other Gag components. 相似文献73.
74.
Morgane Nudel Fanny Baran-Marszak Jean-Baptiste Bossard Romain Dubois Héloïse Dapvril Jehan Dupuis Kamel Laribi Jacques-Olivier Bay Cécile Tomowiak Brigitte Dreyfus Stéphane Lepretre Hélène Demarquette Frédéric Wallyn Lidwine Wemeau Mathieu Wemeau Stéphanie Poulain Franck Morschhauser Florence Cymbalista Charles Herbaux 《British journal of haematology》2019,186(5):e126-e130
75.
Bougeard M Le Saux JC Teillon A Belloir J Le Mennec C Thome S Durand G Pommepuy M 《Journal of water and health》2011,9(3):467-482
The present study sought to identify Escherichia coli sources in a small catchment and to use the agro-hydrological model soil and water assessment tool (SWAT) to estimate their impact on river water quality. The innovative aspects of this research are to assess the hourly variations of fecal contamination and to take these variations into account in the model to provide a better evaluation of river quality. Thus, water samples were taken weekly at the river outlet (n = 4) and 24-h monitoring sessions were performed during low and high-flow periods (n = 74). E. coli variations were found to be primarily linked to rainfall and not to resuspension mechanisms. Subdaily fluctuations and deviations were ±0.33 log10 cfu/100 mL and ±0.70 log10 cfu/100 mL for dry (<3 mm/day) and wet (>3 mm/day) weather, respectively. After river flow calibration, all known pollution sources (septic systems, manure spreading, farm discharges) were introduced into SWAT. The model reproduced the fecal contamination in the river and the use of subdaily deviations allowed us to evaluate the simulation quality and compare grab samplings with simulated daily E. coli concentration, thus confirming that the performance of the model is better when additional information on hourly concentration variations is used. 相似文献
76.
Elizabeth C. Hair Jeff Niederdeppe Jessica M. Rath Morgane Bennett Alexa Romberg Lindsay Pitzer 《Journal of health communication》2020,25(3):223-231
Mass media campaigns are one of the most effective population-level interventions for the prevention of tobacco use. However, accurately evaluating the effectiveness of these campaigns presents several challenges, particularly as campaign delivery becomes increasingly fractured across media platforms. There are a number of weaknesses associated with traditional, individual-level measures of campaign exposure in an increasingly socially networked, digital media ecosystem. This study evaluated the national truth® campaign using a novel method to measure campaign exposure through an aggregate weekly exogenous measure of awareness. We generated this exogenous measure from a continuous, cross-sectional tracking survey to predict intentions to smoke and current tobacco use among youth in the United States. Results from multi-level models indicated that weeks with aggregate campaign awareness greater than 65% were associated with lower odds of current tobacco use. We conclude with a discussion of implications and practical considerations for using this method for media campaign evaluation. 相似文献
77.
78.
Spontaneous neuronal activity was recorded extracellularly from isolated single units in frontal neocortex and caudate nucleus of young and aged F344 rats anesthetized with urethane. Average firing rates, mean interspike intervals (ISI)±standard deviations, and ISI frequency histograms were computed and analyzed by microprocessor. For frontal cortex cells (N=226), there was a nonsignificant trend toward slower average discharge rates in the old group. However, a significantly longer mean ISI and proportionally more very slow firing cells (<I Hz) were observed in old rats. A laminar analysis of frontal cortex unit activity in young animals showed average discharge rates to be distributed somewhat evenly throughout the cortical mantle with the exception of the zone 1200–1400 μ beneath brain surface. This depth corresponds approximately to layer V where a 50% increase in mean firing rate in young animals was observed. In aged animals, this increased cell firing in layer V was absent, while mean discharge rates in other laminae remained essentially the same in the young and old rat groups. Caudate nucleus cells (n=70) showed a significant shift towards fewer fast discharging cells in old rats, with the average firing rate diminished by one-third. Although more brain regions need to be examined in a similar fashion, the consistency of the present results with those previously reported for the brainstem and cerebellum suggests that slower firing rates and longer ISIs are likely to be wide-spread throughout the brains of aged rats. 相似文献
79.
Karima Hammas Jacqueline Yaouanq Morgane Lannes Gilles Edan Jean-François Viel 《International journal of health geographics》2017,16(1):35
Background
Despite intensive research over several decades, the etiology of multiple sclerosis (MS) remains poorly understood, although environmental factors are supposedly implicated. Our goal was to identify spatial clusters of MS incident cases at the small-area level to provide clues to local environmental risk factors that might cause or trigger the disease.Methods
A population-based and multi-stage study was performed in the French Brittany region to accurately ascertain the clinical onset of disease during the 2000–2004 period. The municipality of residence at the time of clinical onset was geocoded. To test for the presence of MS incidence clusters and to identify their approximate locations, we used a spatial scan statistic. We adjusted for socioeconomic deprivation, known to be strongly associated with increased MS incident rates, and scanned simultaneously for areas with either high or low rates. Sensitivity analyses (focusing on relapsing-remitting forms and/or places of residence available within the year following clinical onset) were performed.Results
A total of 848 incident cases of MS were registered in Brittany, corresponding to a crude annual incidence rate of 5.8 per 100,000 inhabitants. The spatial scan statistic did not find a significant cluster of MS incidence in either the primary analysis (p value ≥ 0.56) or in the sensitivity analyses (p value ≥ 0.16).Conclusion
The findings of this study indicate that MS incidence is not markedly affected across space, suggesting that in the years preceding the first clinical expression of the disease, no environmental trigger is operative at the small-area population level in the French Brittany region.80.
Lebreton Morgane Malgouyres Jean-Michel Carayon Jean-Luc Bonnafé Elsa Géret Florence 《Ecotoxicology (London, England)》2021,30(9):1880-1892
Ecotoxicology - Psychoactive drugs have emerged as contaminants over the last few decades. These drugs are frequently prescribed and poorly eliminated by wastewater treatment plants, and many are... 相似文献