排序方式: 共有119条查询结果,搜索用时 765 毫秒
41.
Manuele MG Ferraro G Barreiro Arcos ML López P Cremaschi G Anesini C 《Life sciences》2006,79(21):2043-2048
Some coumarins possess enhancing effects on lymphocyte mitogen responsiveness. In this investigation, the activity of scopoletin, a coumarin that has been isolated from different plants and in this case specifically from T. cordata Mill., was evaluated. For this purpose, normal T lymphocytes and a hyperproliferative T lymphoma cell line were used. Scopoletin was found to exert a dual action on tumoral lymphocytes exhibiting both a cytostatic and a cytotoxic effect. These effects varied with the concentrations analysed and the time of cell incubation (EC(50): 251+/-15 microg/ml) and were associated to the induction of apoptosis. Scopoletin induced cell proliferation on normal T lymphocytes (Proliferation stimulation index: 1 microg/ml scopoletin: 1.26+/-0.1; 10 microg/ml scopoletin: 3+/-0.25; 100 microg/ml scopoletin: 1.86+/-0.08); this stimulatory action was found to be due to the interaction with kinase C (PKC) protein. These results indicate that scopoletin could be a potential antitumoral compound to be used for cancer treatment. 相似文献
42.
Bjørn Anders Sim Sarah King Henry Patouillard Laure Margni Manuele Hauschild Michael Zwicky Ryberg Morten 《The International Journal of Life Cycle Assessment》2020,25(11):2241-2254
The International Journal of Life Cycle Assessment - The planetary boundaries framework contains regional boundaries in addition to global boundaries. Geographically resolved methods to assess... 相似文献
43.
Joseph B. Sempa Agnes N. Kiragga Barbara Castelnuovo Moses R. Kamya Yukari C. Manabe 《PloS one》2013,8(8)
Introduction
There is conflicting data on long-term CD4 immune recovery after combination antiretroviral therapy (ART) in resource-limited settings. Virologic suppression is rarely documented in cohorts from sub-Saharan Africa so objective evidence of adherence is biologically unsubstantiated. We sought to investigate long-term patterns of immune recovery in Ugandan patients on ART with sustained viral suppression.Methods
A prospective cohort of patients starting ART between April, 2004 and April, 2005 at the Infectious Diseases Institute with sustained viral suppression (viral load ≤400 copies/ml at month 6 and 12) while on first-line ART. Propensity scores were used to adjust for treatment allocation (nevirapine or efavirenz) at ART initiation. Data were analyzed using Kaplan Meier methods and cross-sectional time series regression.Results
Three hundred and fifty-six patients were included in the analysis.71.6% were female, 87% in WHO stage 3 or 4, median age was 37 years, (IQR:32–43), and median CD4 count was 108 cells/µL, (IQR:35–174) at ART start. At multivariable analysis, lower immune recovery (measured by change in CD4 from ART start at each time interval) was associated with male-gender (-59, 95% CI: 90, -28, P<0.001), baseline CD4 count of 101–200 cells/µL (-35, 95% CI: 62, -9, P=0.009) and >200 (-64, 95% CI: 101, -26, P=0.001), and use of AZT at baseline (-47, 95% CI: -74, -20, P=0.001). Median time to reach >400 cells/µL was longer in males (197.4 weeks, IQR:119.9–312.0), compared to females (144.7 weeks, IQR:96.6–219.7, P<0.001). The cumulative probability of attaining CD4 >400 cells/µL over 7 years was higher in females compared to males (P<0.001).Conclusions
There was long-term, continuous, immunologic recovery up to 7 years after ART initiation in an urban Ugandan cohort. Virologically suppressed women had better sustained immune recovery than men. Men take longer to immune reconstitute and have a lower probability of reaching a CD4 cell count >400 cells/µL. The biologic mechanisms of these gender differences need further exploration. 相似文献44.
45.
Agnes N. Kiragga Barbara Castelnuovo Rachel Musomba Jonathan Levin Andrew Kambugu Yukari C. Manabe Constantin T. Yiannoutsos Noah Kiwanuka 《PloS one》2013,8(12)
Background
In sub-Saharan Africa, a large proportion of HIV positive patients on antiretroviral therapy (ART) are lost to follow-up, some of whom are dead. The objective of this study was to validate methods used to correct mortality estimates for loss-to-follow-up using a cohort with complete death ascertainment.Methods
Routinely collected data from HIV patients initiating first line antiretroviral therapy (ART) at the Infectious Diseases Institute (IDI) (Routine Cohort) was used. Three methods to estimate mortality after initiation were: 1) standard Kaplan-Meier estimation (uncorrected method) that uses passively observed data; 2) double-sampling methods by Frangakis and Rubin (F&R) where deaths obtained from patient tracing studies are given a higher weight than those passively ascertained; 3) Nomogram proposed by Egger et al. Corrected mortality estimates in the Routine Cohort, were compared with the estimates from the IDI research observational cohort (Research Cohort), which was used as the “gold-standard”.Results
We included 5,633 patients from the Routine Cohort and 559 from the Research Cohort. Uncorrected mortality estimates (95% confidence interval [1]) in the Routine Cohort at 1, 2 and 3 years were 5.5% (4.9%–6.3%), 6.6% (5.9%–7.5%) and 7.4% (6.5%–8.5%), respectively. The F&R corrected estimates at 1, 2 and 3 years were 11.2% (5.8%–21.2%), 15.8% (9.9%–24.8%) and 18.5% (12.3% –27.2%) respectively. The estimates obtained from the Research Cohort were 15.6% (12.8%–18.9%), 17.5% (14.6%–21.0%) and 19.0% (15.3%–21.9%) at 1, 2 and 3 years respectively. Using the nomogram method in the Routine Cohort, the corrected programme-level mortality estimate in year 1 was 11.9% (8.0%–15.7%).Conclusion
Mortality adjustments provided by the F&R and nomogram methods are adequate and should be employed to correct mortality for loss-to-follow-up in large HIV care centres in Sub-Saharan Africa. 相似文献46.
Anna Kounina Manuele Margni Jean-Baptiste Bayart Anne-Marie Boulay Markus Berger Cecile Bulle Rolf Frischknecht Annette Koehler Llorenç Milà i Canals Masaharu Motoshita Montserrat Núñez Gregory Peters Stephan Pfister Brad Ridoutt Rosalie van Zelm Francesca Verones Sebastien Humbert 《The International Journal of Life Cycle Assessment》2013,18(3):707-721
47.
Calabresi L Baldassarre D Simonelli S Gomaraschi M Amato M Castelnuovo S Frigerio B Ravani A Sansaro D Kauhanen J Rauramaa R de Faire U Hamsten A Smit AJ Mannarino E Humphries SE Giral P Veglia F Sirtori CR Franceschini G Tremoli E 《Journal of lipid research》2011,52(8):1569-1574
Lecithin:cholesterol acyltransferase (LCAT) is the enzyme responsible for cholesterol esterification in plasma. LCAT is a major factor in HDL remodeling and metabolism, and it has long been believed to play a critical role in macrophage reverse cholesterol transport (RCT). The effect of LCAT on human atherogenesis is still controversial. In the present study, the plasma LCAT concentration was measured in all subjects (n = 540) not on drug treatment at the time of enrollment in the multicenter, longitudinal, observational IMPROVE study. Mean and maximum intima-media thickness (IMT) of the whole carotid tree was measured by B-mode ultrasonography in all subjects. In the entire cohort, LCAT quartiles were not associated with carotid mean and maximum IMT (P for trend 0.95 and 0.18, respectively), also after adjustment for age, gender, HDL-cholesterol (HDL-C), and triglycerides. No association between carotid IMT and LCAT quartiles was observed in men (P=0.30 and P=0.99 for mean and maximum IMT, respectively), whereas carotid IMT increased with LCAT quartiles in women (P for trend 0.14 and 0.019 for mean and maximum IMT, respectively). The present findings support the concept that LCAT is not required for an efficient reverse cholesterol transport and that a low plasma LCAT concentration and activity is not associated with increased atherosclerosis. 相似文献
48.
Massone S Vassallo I Castelnuovo M Fiorino G Gatta E Robello M Borghi R Tabaton M Russo C Dieci G Cancedda R Pagano A 《The Journal of cell biology》2011,193(5):851-866
Alternative splicing generates protein isoforms that are conditionally or differentially expressed in specific tissues. The discovery of factors that control alternative splicing might clarify the molecular basis of biological and pathological processes. We found that IL1-α-dependent up-regulation of 38A, a small ribonucleic acid (RNA) polymerase III-transcribed RNA, drives the synthesis of an alternatively spliced form of the potassium channel-interacting protein (KCNIP4). The alternative KCNIP4 isoform cannot interact with the γ-secretase complex, resulting in modification of γ-secretase activity, amyloid precursor protein processing, and increased secretion of β-amyloid enriched in the more toxic Aβ x-42 species. Notably, synthesis of the variant KCNIP4 isoform is also detrimental to brain physiology, as it results in the concomitant blockade of the fast kinetics of potassium channels. This alternative splicing shift is observed at high frequency in tissue samples from Alzheimer's disease patients, suggesting that RNA polymerase III cogenes may be upstream determinants of alternative splicing that significantly contribute to homeostasis and pathogenesis in the brain. 相似文献
49.
Kawai S Urban J Piccolis M Panchaud N De Virgilio C Loewith R 《Eukaryotic cell》2011,10(10):1367-1369
TORC1-dependent phosphorylation of Saccharomyces cerevisiae Sch9 was dramatically reduced upon exposure to a protonophore or in respiration-incompetent ρ(0) cells but not in respiration-incompetent pet mutants, providing important insight into the molecular mechanisms governing interorganellar signaling in general and retrograde signaling in particular. 相似文献
50.
Evaluating the variability of aquatic acidification and photochemical ozone formation characterization factors for Canadian emissions 总被引:1,自引:0,他引:1
Samuel Fréchette-Marleau Valérie Bécaert Manuele Margni Réjean Samson Louise Deschênes 《The International Journal of Life Cycle Assessment》2008,13(7):593-604
Background, aim, and scope The Canadian life cycle impact assessment method LUCAS proposes a characterization of the impact categories aquatic acidification
and photochemical ozone formation using a resolution scale based on 15 terrestrial ecozones. Each ecozone represents areas
of the country which can be identified easily by general living (biotic) and nonliving (abiotic) characteristics. The three
main purposes of this research are to improve the characterization models of both impact categories including regional exposure
and effect factors, to investigate what is the best resolution scale between Canadian provinces or ecozones, and to analyze
the extent of spatial variability.
Materials and methods A model framework accounting for variability in fate, exposure and effect factors has been elaborated. The same fate factor,
based on Advanced Statistical Trajectory Regional Air Pollution matrices, applies to both impact categories. For the aquatic
acidification impact category, the fate factor also accounts for the fraction of the deposition transferred to the aquatic
ecosystem. The exposure factor for this impact category is considered to be 1 and the effect factor is based on the critical
load exceedance, where the potential impacts are only considered in provinces or ecozones in which the critical load is exceeded.
For the photochemical ozone formation impact category, the exposure factor is considered to be proportional to the population
density in each province or ecozone, and the effect factor is represented by the chemical reactivity estimated with the maximum
incremental reactivity model. The calculation of the new characterization factors using both a province-based and ecozone
resolution scale was performed using a matrix which converts data from one resolution scale to another.
Results Results with the inclusion of the effect and the exposure factors show that the spatial variability between provinces remains
within a factor of 10 and 5 for aquatic acidification and photochemical ozone formation, respectively.
Discussion Analysis of the results show that regionalization by province is preferable to regionalization by ecozone. It is more accurate
in regard to atmospheric modeling and more representative of population distribution. However, averaging the fate factor and
the population density over a whole province results in a serious limitation.
Conclusions The spatial variability of characterization factors between provinces is in the same order of magnitude as the overall range
between chemicals for aquatic acidification while much smaller for photochemical ozone formation. Hence, at this stage of
knowledge, province-based regionalization seems to be more relevant for the aquatic acidification impact category than for
photochemical ozone formation.
Recommendations and perspectives Research must be pursued to integrate a better transport and deposition model with improved spatial capabilities and a successive
modeling step properly describing the cause–effect chain up to the damage level, such as the biotic environment and the human
population. 相似文献