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41.
Alexandru Coman Daniel N. Maftei Whitney S. Krueger Gary L. Heil Razvan M. Chereches Emanuela Sirlincan Paul Bria Claudiu Dragnea Iosif Kasler Marissa A. Valentine Gregory C. Gray 《PloS one》2014,9(5)
Background
In this prospective study we sought to examine seroepidemiological evidence for acute zoonotic influenza virus infection among Romanian agricultural workers.Methods
Sera were drawn upon enrollment (2009) and again at 12 and 24 months from 312 adult agriculture workers and 51 age-group matched controls. Participants were contacted monthly for 24 months and queried regarding episodes of acute influenza-like illnesses (ILI). Cohort members meeting ILI criteria permitted respiratory swab collections as well as acute and convalescent serum collection. Serologic assays were performed against 9 avian, 3 swine, and 3 human influenza viruses.Results
During the two-year follow-up, a total of 23 ILI events were reported. Two subjects'' specimens were identified as influenza A by rRT-PCR. During the follow-up period, three individuals experienced elevated microneutralization antibody titers ≥1∶80 against three (one each) avian influenza viruses: A/Teal/Hong Kong/w312/97(H6N1), A/Hong Kong/1073/1999(H9N2), or A/Duck/Alberta/60/1976(H12N5). However, none of these participants met the criteria for poultry exposure. A number of subjects demonstrated four-fold increases over time in hemagglutination inhibition (HI) assay titers for at least one of the three swine influenza viruses (SIVs); however, it seems likely that two of these three responses were due to cross-reacting antibody against human influenza. Only elevated antibody titers against A/Swine/Flanders/1/1998(H3N2) lacked evidence for such confounding. In examining risk factors for elevated antibody against this SIV with multiple logistic regression, swine exposure (adjusted OR = 1.8, 95% CI 1.1–2.8) and tobacco use (adjusted OR = 1.8; 95% CI 1.1–2.9) were important predictors.Conclusions
While Romania has recently experienced multiple incursions of highly pathogenic avian influenza among domestic poultry, this cohort of Romanian agriculture workers had sparse evidence of avian influenza virus infections. In contrast, there was evidence, especially among the swine exposed participants, of infections with human and one swine H3N2 influenza virus. 相似文献42.
Anika Wranke Benjamin Heidrich Stefanie Ernst Beatriz Calle Serrano Florin Alexandru Caruntu Manuela Gabriela Curescu Kendal Yalcin Selim Gürel Stefan Zeuzem Andreas Erhardt Stefan Lüth George V. Papatheodoridis Birgit Bremer Judith Stift Jan Grabowski Janina Kirschner Kerstin Port Markus Cornberg Christine S. Falk Hans-Peter Dienes Svenja Hardtke Michael P. Manns Cihan Yurdaydin Heiner Wedemeyer HIDIT- Study Group 《PloS one》2014,9(7)
Background
Hepatitis delta frequently leads to liver cirrhosis and hepatic decompensation. As treatment options are limited, there is a need for biomarkers to determine disease activity and to predict the risk of disease progression. We hypothesized that anti-HDV IgM could represent such a marker.Methods
Samples of 120 HDV-infected patients recruited in an international multicenter treatment trial (HIDIT-2) were studied. Anti-HDV IgM testing was performed using ETI-DELTA-IGMK-2-assay (DiaSorin). In addition, fifty cytokines, chemokines and angiogenetic factors were measured using multiplex technology (Bio-Plex System). A second independent cohort of 78 patients was studied for the development of liver-related clinical endpoints (decompensation, HCC, liver transplantation or death; median follow up of 3.0 years, range 0.6–12).Results
Anti-HDV IgM serum levels were negative in 18 (15%), low (OD<0.5) in 76 (63%), and high in 26 (22%) patients of the HIDIT-2 cohort. Anti-HDV IgM were significantly associated with histological inflammatory (p<0.01) and biochemical disease activity (ALT, AST p<0.01). HDV replication was independent from anti-HDV IgM, however, low HBV-DNA levels were observed in groups with higher anti-HDV IgM levels (p<0.01). While high IP-10 (CXCL10) levels were seen in greater groups of anti-HDV IgM levels, various other antiviral cytokines were negatively associated with anti-HDV IgM. Associations between anti-HDV IgM and ALT, AST, HBV-DNA were confirmed in the independent cohort. Clinical endpoints occurred in 26 anti-HDV IgM positive patients (39%) but in only one anti-HDV IgM negative individual (9%; p = 0.05).Conclusions
Serum anti-HDV IgM is a robust, easy-to-apply and relatively cheap marker to determine disease activity in hepatitis delta which has prognostic implications. High anti-HDV IgM levels may indicate an activated interferon system but exhausted antiviral immunity. 相似文献43.
Modelled as finite homogeneous Markov chains, probabilistic cellular automata with local transition probabilities in (0, 1) always posses a stationary distribution. This result alone is not very helpful when it comes to predicting the final configuration; one needs also a formula connecting the probabilities in the stationary distribution to some intrinsic feature of the lattice configuration. Previous results on the asynchronous cellular automata have showed that such feature really exists. It is the number of zero-one borders within the automaton''s binary configuration. An exponential formula in the number of zero-one borders has been proved for the 1-D, 2-D and 3-D asynchronous automata with neighborhood three, five and seven, respectively. We perform computer experiments on a synchronous cellular automaton to check whether the empirical distribution obeys also that theoretical formula. The numerical results indicate a perfect fit for neighbourhood three and five, which opens the way for a rigorous proof of the formula in this new, synchronous case. 相似文献
44.
45.
Andrea Shafer Alexandru Iordan Roberto Cabeza Florin Dolcos 《Journal of visualized experiments : JoVE》2011,(51)
Emotional events tend to be better remembered than non-emotional events1,2. One goal of cognitive and affective neuroscientists is
to understand the neural mechanisms underlying this enhancing effect of emotion on memory. A method that has proven particularly influential in the
investigation of the memory-enhancing effect of emotion is the so-called subsequent memory paradigm (SMP). This method was originally used to investigate the
neural correlates of non-emotional memories3, and more recently we and others also applied it successfully to studies of emotional memory (reviewed in4, 5-7).
Here, we describe a protocol that allows investigation of the neural correlates of the memory-enhancing effect of emotion using the SMP in conjunction with
event-related functional magnetic resonance imaging (fMRI). An important feature of the SMP is that it allows separation of brain activity specifically
associated with memory from more general activity associated with perception. Moreover, in the context of investigating the impact of emotional stimuli,
SMP allows identification of brain regions whose activity is susceptible to emotional modulation of both general/perceptual and memory-specific processing.
This protocol can be used in healthy subjects8-15, as well as in clinical patients where there are alterations in the neural correlates of emotion perception
and biases in remembering emotional events, such as those suffering from depression and post-traumatic stress disorder (PTSD)16, 17. Download video file.(95M, mov) 相似文献
46.
47.
Alexandru Vasincu Christiana M. Neophytou Simon Vlad Luca Krystyna Skalicka‐Wo
niak Anca Miron Andreas I. Constantinou 《Journal of biochemical and molecular toxicology》2020,34(3)
The aim of this study was to evaluate the impact that 6‐O‐(3″, 4″‐di‐O‐trans‐cinnamoyl)‐α‐ l ‐rhamnopyranosylcatalpol (Dicinn) and verbascoside (Verb), two compounds simultaneously reported in Verbascum ovalifolium, have on tumor cell viability, apoptosis, cell cycle kinetics, and intracellular reactive oxygen species (ROS) level. At 100 µg/mL and 48 hours incubation time, Dicinn and Verb produced good cytotoxic effects in A549, HT‐29, and MCF‐7 cells. Dicinn induced cell‐cycle arrest at the G0/G1 phase and apoptosis, whereas Verb increased the population of subG1 cells and cell apoptosis rates. Furthermore, the two compounds exhibited time‐dependent ROS generating effects in tumor cells (1‐24 hours). Importantly, no cytotoxic effects were induced in nontumor MCF‐10A cells by the two compounds up to 100 µg/mL. Overall, the effects exhibited by Verb in tumor cells were more potent, which can be correlated with its structural features, such as the presence of phenolic hydroxyl groups. 相似文献
48.
Amr Ali Ahmed Ali Attia Daniela Cioloboc Alexandru Lupan Radu Silaghi-Dumitrescu 《Journal of biological inorganic chemistry》2013,18(1):95-101
It is generally accepted that the catalytic cycles of superoxide reductases (SORs) and cytochromes P450 involve a ferric hydroperoxo intermediate at a mononuclear iron center with a coordination sphere consisting of four equatorial nitrogen ligands and one axial cysteine thiolate trans to the hydroperoxide. However, although SORs and P450s have similar intermediates, SORs selectively cleave the Fe–O bond and liberate peroxide, whereas P450s cleave the O–O bond to yield a high-valent iron center. This difference has attracted the interest of researchers, and is further explored here. Meta hybrid DFT (M06-2X) results for the reactivity of the putative peroxo/hydroperoxo reaction intermediates in the catalytic cycle of SORs were found to indicate a high-spin preference in all cases. An exploration of the energy profiles for Fe–O and O–O bond cleavage in all spin states in both ferric and ferrous models revealed that Fe–O bond cleavage always occurs more easily than O–O bond cleavage. While O–O bond cleavage appears to be thermodynamically and kinetically unfeasible in ferric hydrogen peroxide complexes, it could occur as a minor (significantly disfavored) side reaction in the interaction of ferrous SOR with hydrogen peroxide. 相似文献
49.
Endogenous circadian rhythms in pigment composition induce changes in photochemical efficiency in plant canopies 下载免费PDF全文
José Ignacio García‐Plazaola Beatriz Fernández‐Marín Juan Pedro Ferrio Josu G. Alday Günter Hoch Damien Landais Alexandru Milcu David T. Tissue Jordi Voltas Arthur Gessler Jacques Roy Víctor Resco de Dios 《Plant, cell & environment》2017,40(7):1153-1162
There is increasing evidence that the circadian clock is a significant driver of photosynthesis that becomes apparent when environmental cues are experimentally held constant. We studied whether the composition of photosynthetic pigments is under circadian regulation, and whether pigment oscillations lead to rhythmic changes in photochemical efficiency. To address these questions, we maintained canopies of bean and cotton, after an entrainment phase, under constant (light or darkness) conditions for 30–48 h. Photosynthesis and quantum yield peaked at subjective noon, and non‐photochemical quenching peaked at night. These oscillations were not associated with parallel changes in carbohydrate content or xanthophyll cycle activity. We observed robust oscillations of Chl a/b during constant light in both species, and also under constant darkness in bean, peaking when it would have been night during the entrainment (subjective nights). These oscillations could be attributed to the synthesis and/or degradation of trimeric light‐harvesting complex II (reflected by the rhythmic changes in Chl a/b), with the antenna size minimal at night and maximal around subjective noon. Considering together the oscillations of pigments and photochemistry, the observed pattern of changes is counterintuitive if we assume that the plant strategy is to avoid photodamage, but consistent with a strategy where non‐stressed plants maximize photosynthesis. 相似文献
50.
Christelle Elia Alexis Karamanos Alexandru Dregan Majella OKeeffe Ingrid Wolfe Jane Sandall Craig Morgan J. Kennedy Cruickshank Reeta Gobin Rainford Wilks Seeromanie Harding 《PLoS medicine》2020,17(12)
BackgroundAdolescents and young people (10–24 years old) in the Latin America and the Caribbean (LAC) region represent approximately 25% of the region’s population. Since the 2008 global economic crisis, the pace of reduction in poverty and income inequality in the LAC region has stalled. The region is characterised by high levels of inequities and is also vulnerable to many natural disasters. Food systems are changing with increased availability and marketing of packaged and fast foods and sugar-sweetened drinks. Adolescence is a formative phase of the life course with multiple physical, emotional and social changes which can make them vulnerable to health problems. We assess the potential impact of macro-determinants, human and economic development as well as income inequality, on 2 top-ranking regional priorities for adolescent nutrition and mental health, using measures of overweight and suicidal ideation and planning which some have shown to be associated.Methods and findingsThe Global School-based Health Survey (GSHS) is a nationally representative self-administered, school-based survey. We examined overweight/obesity and suicidal ideation with planning by gross domestic product (GDP) per capita or human development index (HDI) in 10–19-year-old adolescents from 21 LAC countries between 2009 and 2013. Sample sizes varied from 943 in Anguilla to 27,988 in Argentina. A total of 55,295 adolescents had a measure of overweight/obesity status, and 59,061 adolescents reported about suicidal ideation with planning. There was equal representation by sex in the surveys (52% girls and 48% boys). A total of 28.8% of boys and 28.1% of girls had overweight/obesity, and 7.5% of boys and 17.5% of girls reported suicidal ideation with planning over the last 12 months. Adjusted for individual socioeconomic and risk behaviours, and relative to the highest GDP per capita tertile, the middle tertile was associated with 42% (95% confidence interval (CI) 59% to 17%, p = 0.003) and 32% (95% CI 60% to 5%, p = 0.023), and the lowest tertile with 40% (95% CI 55% to 19%, p = 0.001) and 46% (95% CI 59% to 29%, p < 0.001) lower chances of overweight/obesity for girls and boys, respectively. A similar positive effect was seen with HDI, with lowest chances of overweight in the lowest tertile compared with the highest tertile for both sexes. Overweight/obesity was positively related with suicidal ideation with planning for girls (odds ratio (OR) 1.12, 95% CI 1.02 to 1.22, p = 0.009) and weakly related for boys (OR 1.09, 95% CI 0.96 to 1.24, p = 0.182). In contrast to overweight/obesity status, suicidal ideation with planning was not related to macro-level indices despite both outcomes sharing common individual socioeconomic and risk behaviour correlates. Limitations include the dominance of Argentinians in the sample (40%), the exclusion of vulnerable adolescents who dropped out of school, and reporting bias due to stigma of mental health–related issues.ConclusionsThis study shows that economic and human development were positively associated with adolescent overweight/obesity but not with suicidal ideation with planning. We also observed an interconnectedness between overweight/obesity and suicide ideation with planning among girls. These findings highlight the importance of strategies that engage with both upstream and downstream determinants to improve adolescent nutrition and mental health. 相似文献