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171.
172.
Ana Freitas Ribeiro Alessandra Cristina Guedes Pellini Beatriz Yuko Kitagawa Daniel Marques Geraldine Madalosso Gerrita de Cassia Nogueira Figueira Jo?o Fred Ricardo Kerti Mangabeira Albernaz Telma Regina Marques Pinto Carvalhanas Dirce Maria Trevisan Zanetta 《PloS one》2015,10(3)
This case-control study aimed to assess the risk factors for death from influenza A(H1N1)pdm09 in patients with laboratory confirmation, who had severe acute respiratory illness-SARI and were hospitalized between June 28th and August 29th 2009, in the metropolitan regions of São Paulo and Campinas, Brazil. Medical charts of all the 193 patients who died (cases) and the 386 randomly selected patients who recovered (controls) were investigated in 177 hospitals. Household interviews were conducted with those who had survived and the closest relative of those who had died. 73.6% of cases and 38.1% of controls were at risk of developing influenza-related complications. The 18-to-59-year age group (OR = 2.31, 95%CI: 1.31–4.10 (reference up to 18 years of age)), presence of risk conditions for severity of influenza (OR = 1.99, 95%CI: 1.11–3.57, if one or OR = 6.05, 95%CI: 2.76–13.28, if more than one), obesity (OR = 2.73, 95%CI: 1.28–5.83), immunosuppression (OR = 3.43, 95%CI: 1.28–9.19), and search for previous care associated with the hospitalization (OR = 3.35, 95%CI: 1.75–6.40) were risk factors for death. Antiviral treatment performed within 72 hours of the onset of symptoms (OR = 0.17, 95%CI: 0.08–0.37, if within 48hours, and OR = 0.30, 95%CI: 0.11–0.81, if between 48 and 72 hours) was protective against death. The identification of high-risk patients and early treatment are important factors for reducing morbi-mortality from influenza. 相似文献
173.
IntroductionThe allostatic load (AL) index is a multi-systemic measure of physiologic dysregulation known to be associated with chronic exposure to stress and adverse health outcomes. We examined the relationship between AL and serum 25-hydroxyvitamin D (25(OH)D) concentration in non-institutionalized US adults.MethodsData from the Third National Health and Nutrition Examination Survey (NHANES III, 1988–94) were used to calculate two versions of AL including 9 biomarkers and another two with 14 biomarkers (systolic and diastolic blood pressure, pulse rate, serum cholesterol, serum HDL-cholesterol, glycated hemoglobin, sex-specific waist-to-hip ratio, serum albumin, and serum C-reactive protein for AL1, and, additionally body mass index, serum triglyceride, serum creatinine, and serum herpes I & II antibodies for AL2), each set defined by predefined cut-offs or by quartiles. Serum vitamin D concentration was ranked into quartiles. Logistic regression, Poisson regression and linear regression were used to examine the association of serum 25(OH)D concentrations on AL, after adjusting for biological, physiological, socioeconomic, lifestyle, and health variables.ResultsOdds Ratios (OR) for high AL of the lowest 25(OH)D serum quartile were between 1.45 (95% CI: 1.28, 1.67) and 1.79 (95% CI: 1.39, 2.32) for the fully adjusted model, depending on AL version. Inverse relationships between vitamin D serum concentrations were observed for all AL versions and every adjustment. This relationship was consistent after stratification by sex, age or ethnic background. Sensitivity to low 25(OH)D concentrations was highest among the youngest group (20–39 years) with an OR of 2.11 (95% CI: 1.63, 2.73) for the lowest vitamin D quartile Q1.ConclusionsVitamin D had a consistent and statistically significant inverse association with all tested models of high AL, which remained consistent after adjusting for biological, socioeconomic, lifestyle and health variables. Our study adds evidence linking low 25(OH)D concentrations with poorer health, further-reaching than bone health. 相似文献
174.
Magna C. Paiva Marcelo P. ávila Mariana P. Reis Patrícia S. Costa Regina M. D. Nardi Andréa M. A. Nascimento 《PloS one》2015,10(6)
Bacteria are assumed to efficiently remove organic pollutants from sewage in sewage treatment plants, where antibiotic-resistance genes can move between species via mobile genetic elements known as integrons. Nevertheless, few studies have addressed bacterial diversity and class 1 integron abundance in tropical sewage. Here, we describe the extant microbiota, using V6 tag sequencing, and quantify the class 1 integron-integrase gene (intI1) in raw sewage (RS) and activated sludge (AS). The analysis of 1,174,486 quality-filtered reads obtained from RS and AS samples revealed complex and distinct bacterial diversity in these samples. The RS sample, with 3,074 operational taxonomic units, exhibited the highest alpha-diversity indices. Among the 25 phyla, Proteobacteria, Bacteroidetes and Firmicutes represented 85% (AS) and 92% (RS) of all reads. Increased relative abundance of Micrococcales, Myxococcales, and Sphingobacteriales and reduced pathogen abundance were noted in AS. At the genus level, differences were observed for the dominant genera Simplicispira and Diaphorobacter (AS) as well as for Enhydrobacter (RS). The activated sludge process decreased (55%) the amount of bacteria harboring the intI1 gene in the RS sample. Altogether, our results emphasize the importance of biological treatment for diminishing pathogenic bacteria and those bearing the intI1 gene that arrive at a sewage treatment plant. 相似文献
175.
Current molecular methods to characterize microalgae are time-intensive and expensive. Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) may represent a rapid and economical alternative approach. The objectives of this study were to determine whether MALDI-TOF MS can be used to: 1) differentiate microalgae at the species and strain levels and 2) characterize simple microalgal mixtures. A common protein extraction sample preparation method was used to facilitate rapid mass spectrometry-based analysis of 31 microalgae. Each yielded spectra containing between 6 and 56 peaks in the m/z 2,000 to 20,000 range. The taxonomic resolution of this approach appeared higher than that of 18S rDNA sequence analysis. For example, two strains of Scenedesmus acutus differed only by two 18S rDNA nucleotides, but yielded distinct MALDI-TOF mass spectra. Mixtures of two and three microalgae yielded relatively complex spectra that contained peaks associated with members of each mixture. Interestingly, though, mixture-specific peaks were observed at m/z 11,048 and 11,230. Our results suggest that MALDI-TOF MS affords rapid characterization of individual microalgae and simple microalgal mixtures. 相似文献
176.
Temporal Patterns and Environmental Correlates of Macroinvertebrate Communities in Temporary Streams
Paul K. Botwe Leon A. Barmuta Regina Magierowski Paul McEvoy Peter Goonan Scott Carver 《PloS one》2015,10(11)
Temporary streams are characterised by short periods of seasonal or annual stream flow after which streams contract into waterholes or pools of varying hydrological connectivity and permanence. Although these streams are widespread globally, temporal variability of their ecology is understudied, and understanding the processes that structure community composition in these systems is vital for predicting and managing the consequences of anthropogenic impacts. We used multivariate and univariate approaches to investigate temporal variability in macroinvertebrate compositional data from 13 years of sampling across multiple sites from autumn and spring, in South Australia, the driest state in the driest inhabited continent in the world. We examined the potential of land-use, geographic and environmental variables to predict the temporal variability in macroinvertebrate assemblages, and also identified indicator taxa, that is, those highly correlated with the most significantly associated physical variables. Temporal trajectories of macroinvertebrate communities varied within site in both seasons and across years. A combination of land-use, geographic and environmental variables accounted for 24% of the variation in community structure in autumn and 27% in spring. In autumn, community composition among sites were more closely clustered together relative to spring suggesting that communities were more similar in autumn than in spring. In both seasons, community structure was most strongly correlated with conductivity and latitude, and community structure was more associated with cover by agriculture than urban land-use. Maintaining temporary streams will require improved catchment management aimed at sustaining seasonal flows and critical refuge habitats, while also limiting the damaging effects from increased agriculture and urban developments. 相似文献
177.
Giulliana T. Almeida Regina C. G. Lage Leticia Anderson Thiago M. Venancio Helder I. Nakaya Patrícia A. Miyasato Henrique K. Rofatto Adhemar Zerlotini Eliana Nakano Guilherme Oliveira Sergio Verjovski-Almeida 《PLoS neglected tropical diseases》2015,9(9)
BackgroundTreatment and morbidity control of schistosomiasis relies on a single drug, praziquantel (PZQ), and the selection of resistant worms under repeated treatment is a concern. Therefore, there is a pressing need to understand the molecular effects of PZQ on schistosomes and to investigate alternative or synergistic drugs against schistosomiasis.MethodologyWe used a custom-designed Schistosoma mansoni expression microarray to explore the effects of sublethal doses of PZQ on large-scale gene expression of adult paired males and females and unpaired mature females. We also assessed the efficacy of PZQ, omeprazole (OMP) or their combination against S. mansoni adult worms with a survival in vitro assay.ConclusionsFunctional analysis of gene interaction networks is an important approach that can point to possible novel synergistic drug candidates. We demonstrated the potential of this strategy by showing that PZQ in combination with OMP displayed increased efficiency against S. mansoni adult worms in vitro when compared with either drug alone. 相似文献
178.
Milton Maciel Jr. Fábia da Silva Pereira Cruz Marli Tenório Cordeiro Márcia Archer da Motta Klécia Marília Soares de Melo Cassemiro Rita de Cássia Carvalho Maia Regina Célia Bressan Queiroz de Figueiredo Ricardo Galler Marcos da Silva Freire Joseph Thomas August Ernesto T. A. Marques Rafael Dhalia 《PLoS neglected tropical diseases》2015,9(4)
Attenuated yellow fever (YF) virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE) or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE), aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies. 相似文献
179.
Marcelo Moura Linhares Renato José Affonso Jr Luciano de Souza Viana Sandra Regina Morini Silva Marcos Vinicius Araujo Denadai Silvia Regina Caminada de Toledo Delcio Matos 《PloS one》2015,10(12)
Objective
To evaluate the relationship between the expression profiles of 84 extracellular matrix (ECM) genes and the prognosis of patients with colorectal cancer (CRC).Methods
This retrospective study included 114 patients with stage I–IV CRC who underwent primary tumour resection. Quantitative real-time PCR and immunohistochemistry assays were conducted using primary tumour samples. Kaplan-Meier survival curves were also generated to identify differences in global survival (GS) and disease-free survival (DFS) for the hypo- or hyperexpression status of each marker. The log-rank test was used to verify whether the differences were significant. Stepwise Cox regression models were also used to identify the risk factors associated with GS and DFS in a multivariate mode, and then were used to score the risk of death associated with each marker, either independently or in association.Results
In the univariate analyses, significant differences in GS in relation to the expression profiles of ITGAV (p = 0.001), ITGA3 (p = 0.002), ITGA6 (p = 0.001), SPARC (p = 0.036), MMP9 (p = 0.034), and MMP16 (p = 0.038) were observed. For DFS, significant differences were observed in associated with ITGAV (p = 0.004) and ITGA3 (p = 0.001). However, only the ITGAV and ITGA6 gene markers for GS (hazard ratio (HR) = 3.209, 95% confidence interval (CI) = 1.412–7.293, p = 0.005 and HR = 3.105, 95% CI = 1.367–7.055, p = 0.007, respectively), and ITGA3 for DFS (HR = 3.806, 95% CI = 1.573–9.209, p = 0.003), remained in the final Cox regression models. A scoring system was developed to evaluate the risk of patient death based on the number of markers for the components of the final GS model. Scores of 0, 1, or 2 were associated with the following mean survival rates [CI]: 47.162 [44.613–49.711], 39.717 [35.471–43.964], 30.197 [24.030–36.327], respectively.Conclusions
Multivariate mathematical models demonstrated an association between hyperexpression of the ITGAV and ITGA6 integrins and GS, and also between the ITGA3 integrin and DFS, in patients with colorectal tumours. A risk scoring system based on detected hyperexpression of 0, 1, or 2 markers (e.g., ITGAV and/or ITGA6) was also found to accurately correlate with the GS curves generated for the present cohort. 相似文献180.
Arsenic Exposure Increases Monocyte Adhesion to the Vascular Endothelium,a Pro-Atherogenic Mechanism
Maryse Lemaire Luis Fernando Negro Silva Catherine A. Lemarié Alicia M. Bolt Manuel Flores Molina Regina M. Krohn Judit E. Smits Stéphanie Lehoux Koren K. Mann 《PloS one》2015,10(9)
Epidemiological studies have shown that arsenic exposure increases atherosclerosis, but the mechanisms underlying this relationship are unknown. Monocytes, macrophages and platelets play an important role in the initiation of atherosclerosis. Circulating monocytes and macrophages bind to the activated vascular endothelium and migrate into the sub-endothelium, where they become lipid-laden foam cells. This process can be facilitated by platelets, which favour monocyte recruitment to the lesion. Thus, we assessed the effects of low-to-moderate arsenic exposure on monocyte adhesion to endothelial cells, platelet activation and platelet-monocyte interactions. We observed that arsenic induces human monocyte adhesion to endothelial cells in vitro. These findings were confirmed ex vivo using a murine organ culture system at concentrations as low as 10 ppb. We found that both cell types need to be exposed to arsenic to maximize monocyte adhesion to the endothelium. This adhesion process is specific to monocyte/endothelium interactions. Hence, no effect of arsenic on platelet activation or platelet/leukocyte interaction was observed. We found that arsenic increases adhesion of mononuclear cells via increased CD29 binding to VCAM-1, an adhesion molecule found on activated endothelial cells. Similar results were observed in vivo, where arsenic-exposed mice exhibit increased VCAM-1 expression on endothelial cells and increased CD29 on circulating monocytes. Interestingly, expression of adhesion molecules and increased binding can be inhibited by antioxidants in vitro and in vivo. Together, these data suggest that arsenic might enhance atherosclerosis by increasing monocyte adhesion to endothelial cells, a process that is inhibited by antioxidants. 相似文献