422 research outputs found

    Land use regression modelling of NO2 in São Paulo, Brazil

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    BACKGROUND: Air pollution is a major global public health problem. The situation is most severe in low- and middle-income countries, where pollution control measures and monitoring systems are largely lacking. Data to quantify the exposure to air pollution in low-income settings are scarce. METHODS: In this study, land use regression models (LUR) were developed to predict the outdoor nitrogen dioxide (NO2) concentration in the study area of the Western Region Birth Cohort in Sao Paulo. NO2 measurements were performed for one week in winter and summer at eighty locations. Additionally, weekly measurements at one regional background location were performed over a full one-year period to create an annual prediction. RESULTS: Three LUR models were developed (annual, summer, winter) by using a supervised stepwise linear regression method. The winter, summer and annual models explained 52 %, 75 % and 66 % of the variance (R(2)) respectively. Cross-holdout validation tests suggest robust models. NO2 levels ranged from 43.2 mug/m(3) to 93.4 mug/m(3) in the winter and between 28.1 mug/m(3) and 72.8 mug/m(3) in summer. Based on our annual prediction, about 67 % of the population living in the study area is exposed to NO2 values over the WHO suggested annual guideline of 40 mug/m(3) annual average. CONCLUSION: In this study we were able to develop robust models to predict NO2 residential exposure. We could show that average measures, and therefore the predictions of NO2, in such a complex urban area are substantially high and that a major variability within the area and especially within the season is present. These findings also suggest that in general a high proportion of the population is exposed to high NO2 levels

    Influence of lithium in neuron-glia interaction in hippocampal neurons: preliminary study

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    Recentemente, especial atenção foi dada aos possíveis efeitos neuroprotetores do lítio, especialmente pela descoberta de seus efeitos regulatórios sobre proteínas pró e anti-apoptóticas. O lítio aumenta substancialmente a expressão de proteínas citoprotetoras no sistema nervoso central, tanto no córtex de ratos quanto em células humanas de origem neuronal. Além de ações neuroprotetoras, auxilia na regeneração de axônios no sistema nervoso central de mamíferos. O lítio regula negativamente a expressão e a atividade de enzimas que exercem funções importantes na homeostase cerebral: plasticidade sináptica, neurogênese e fosforilação da proteína tau. Microglia é conhecida por sua importância na neuropatologia. No entanto, sob condições fisiológicas, tais células imunes interagem ativamente com os neurônios, sendo capazes de modular o destino e as funções das sinapses. Essa capacidade das células microgliais sugere as conseqüências de mudanças no fenótipo microglial sob condições patológicas, o que torna relevante o entendimento da interação entre micróglia e outras células cerebrais em desenvolvimento e sua influência na formação de redes neuronais e sinápticas. O presente trabalho tem como objetivo identificar a principal via de integração neurônio-glia ativada pelo tratamento crônico com lítio em neurônios, explorando o uso de ferramentas de bioinformática em dados de microarray. O tratamento de neurônios hipocampais com lítio alterou os genes relacionados a diferentes vias de neuroproteção na dose terapêutica mais alta. Houve dissociação entre a dose terapêutica e sub-terapêutica de lítio na neuroproteção. Portanto, o tratamento em doses terapêuticas (2mM) modificou diferentes vias de sinalização quando comparado com as doses sub-terapêuticas (0,02 e 0,2mM).Recently, special attention has been given to the possible neuroprotective effects of lithium, especially by the discovery of its regulatory effects on pro and anti-apoptotic proteins. Lithium substantially increases the cytoprotective proteins expression in the central nervous system, both in rat cortex and in human cells of neuronal origin. In addition to neuroprotective actions, it aids in the regeneration of axons in the central nervous system of mammals. Lithium negatively regulates the expression and activity of enzymes that exert important functions in cerebral homeostasis: synaptic plasticity, neurogenesis, and phosphorylation of tau protein. Microglia is known for its importance in neuropathology. However, under physiological conditions, such immune cells interact actively with neurons, being able to modulate the fate and functions of the synapses. Such ability of microglial cells suggests the consequences of changes in microglial phenotype under pathological conditions, which makes it relevant to understand the interaction between microglial and other developing brain cells and their influence on the formation of neuronal and synaptic networks. The current work aims to identify the main pathway of neuronal-glia integration activated by chronic treatment with lithium in neurons, exploring the use of bioinformatics tools in microarray data. Treatment of primary hippocampal neurons with lithium changed the genes related to different neuroprotection pathways at the highest therapeutic dose. There was dissociation between the therapeutic and sub-therapeutic dose of lithium in neuroprotection. Therefore, treatment at therapeutic doses (2mM) modified different signaling pathways when compared to the sub-therapeutic dose (0.02 and 0.2mM)

    Land use regression modelling of community noise in São Paulo, Brazil

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    Noise pollution has negative health consequences, which becomes increasingly relevant with rapid urbanization. In low- and middle-income countries research on health effects of noise is hampered by scarce exposure data and noise maps. In this study, we developed land use regression (LUR) models to assess spatial variability of community noise in the Western Region of Sao Paulo, Brazil.We measured outdoor noise levels continuously at 42 homes once or twice during one week in the summer and the winter season. These measurements were integrated with various geographic information system variables to develop LUR models for predicting average A-weighted (dB(A)) day-evening-night equivalent sound levels (Lden) and night sound levels (Lnight). A supervised mixed linear regression analysis was conducted to test potential noise predictors for various buffer sizes and distances between home and noise source.Noise exposure levels in the study area were high with a site average Lden of 69.3 dB(A) ranging from 60.3 to 82.3 dB(A), and a site average Lnight of 59.9 dB(A) ranging from 50.7 to 76.6 dB(A). LUR models had a good fit with a R(2) of 0.56 for Lden and 0.63 for Lnight in a leave-one-site-out cross validation. Main predictors of noise were the inverse distance to medium roads, count of educational facilities within a 400 m buffer, mean Normalized Difference Vegetation Index (NDVI) within a 100 m buffer, residential areas within a 50 m (Lden) or 25 m (Lnight) buffer and slum areas within a 400 m buffer. Our study suggests that LUR modelling with geographic predictor data is a promising and efficient approach for noise exposure assessment in low- and middle-income countries, where noise maps are not available

    Association between community noise and children's cognitive and behavioral development: a prospective cohort study

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    BACKGROUND: Noise exposure has been associated with adverse cognitive and behavioral outcomes in children, but evidence on longitudinal associations between community noise and child development in low- and middle-income countries is rare. We investigated associations between community noise and behavioral and cognitive development in preschool children in Sao Paulo. METHODS: We linked child development data from the Sao Paulo Western Region Birth Cohort with average (Lden) and night-time (Lnight) community noise exposure at children's home, estimated by means of a land use regression model using various predictors (roads, schools, greenness, residential and informal settlements). Outcomes were the Strengths and Difficulties Questionnaire (SDQ) and Regional Project on Child Development Indicators (PRIDI) at 3 years of age and the Child Behavior Checklist (CBCL) and International Development and Early Learning Assessment (IDELA) at 6 years of age. We investigated the relationship between noise exposure and development using cross-sectional and longitudinal regression models. RESULTS: Data from 3385 children at 3 years of age and 1546 children at 6 years of age were analysed. Mean Lden and Lnight levels were 70.3 dB and 61.2 dB, respectively. In cross-sectional analyses a 10 dB increase of Lden above 70 dB was associated with a 32% increase in the odds of borderline or abnormal SDQ total difficulties score (OR = 1.32, 95% CI: 1.04; 1.68) and 0.72 standard deviation (SD) increase in the CBCL total problems z-score (95% CI: 0.55; 0.88). No cross-sectional association was found for cognitive development. In longitudinal analyses, each 10 dB increase was associated with a 0.52 SD increase in behavioral problems (95% CI: 0.28; 0.77) and a 0.27 SD decrease in cognition (95%-CI: 0.55; 0.00). Results for Lnight above 60 dB were similar. DISCUSSION: Our findings suggest that community noise exposure above Lden of 70 dB and Lnight of 60 dB may impair behavioral and cognitive development of preschool children

    Measuring early childhood development in Brazil: validation of the Caregiver Reported Early Development Instruments (CREDI)

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    The present study aims to analyze the psychometric properties and general validity of the Caregiver Reported Early Development Instruments (CREDI) short form for the population-level assessment of early childhood development for Brazilian children under age 3.; The study analyzed the acceptability, test-retest reliability, internal consistency and discriminant validity of the CREDI short-form tool. The study also analyzed the concurrent validity of the CREDI with a direct observational measure (Inter-American Development Bank's Regional Project on Child Development Indicators; PRIDI). The full sample includes 1,265 Brazilian caregivers of children from 0 to 35 months (678 of which comprising an in-person sample and 587 an online sample).; Results from qualitative interviews suggest overall high rates of acceptability. Most of the items showed adequate test-retest reliability, with an average agreement of 84%. Cronbach's alpha suggested adequate internal consistency/inter-item reliability (α>0.80) for the CREDI within each of the six age groups (0-5, 6-11, 12-17, 18-23, 24-29 and 30-35 months of age). Multivariate analyses of construct validity showed that a significant proportion of the variance in CREDI scores could be explained by child gender and family characteristics, most importantly caregiver-reported cognitive stimulation in the home (p<0.0001). Regarding concurrent validity, scores on the CREDI were significantly correlated with overall PRIDI scores within the in-person sample at r=0.46 (p<0.001).; The results suggested that the CREDI short form is a valid, reliable, and acceptable measure of early childhood development for children under the age of 3 years in Brazil

    Success factors for service innovation: a meta-analysis

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    Service sectors form a considerable part of the world economy. Contrary to the logical assumption that service innovation research should represent a significant share of all innovation research, the vast majority of innovation studies focus on products as opposed to services. This research presents a meta-analysis of the antecedents of service innovation performance conducted on 92 independent samples obtained from 114 articles published between 1989 and 2015. This research contributes to our understanding of service innovation in three major ways. First, this is the first meta-analysis that specifically assesses the relative importance of antecedents of service innovation performance, while also pinpointing the differences in meta-analytic findings between antecedents of service and product innovation performance. Whilst there are some universal success factors that transcend the boundaries between services and products, the presence of marked differences implies that it would be wrong to treat the development of new services and new products as the same. Second, the meta-analysis demonstrates that the antecedents of service innovation performance are contingent on the sector context (i.e., explicit versus tacit services). Comparing results between products and services, and between tacit and explicit services, there appears to be a continuum where explicit services sit interstitial between tacit services on one side and products on the other. Third, the meta-analysis compares and contrasts the antecedents of two dimensions of service innovation performance (i.e., commercial success and strategic competitive advantage). Previous meta-analyses treated these two dependent variables collectively, which falls short of identifying issues that may affect management decisions when faced with different objectives. Additionally, this research investigates the effect of several other moderators (i.e., culture, unit of analysis, journal quality, and year of publication) on the relationships between the antecedents and service innovation performance. The results are discussed in relation to their implications for research and managerial practice

    Simcluster: clustering enumeration gene expression data on the simplex space

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    Transcript enumeration methods such as SAGE, MPSS, and sequencing-by-synthesis EST &#x22;digital northern&#x22;, are important high-throughput techniques for digital gene expression measurement. As other counting or voting processes, these measurements constitute compositional data exhibiting properties particular to the simplex space where the summation of the components is constrained. These properties are not present on regular Euclidean spaces, on which hybridization-based microarray data is often modeled. Therefore, pattern recognition methods commonly used for microarray data analysis may be non-informative for the data generated by transcript enumeration techniques since they ignore certain fundamental properties of this space.&#xd;&#xa;&#xd;&#xa;Here we present a software tool, Simcluster, designed to perform clustering analysis for data on the simplex space. We present Simcluster as a stand-alone command-line C package and as a user-friendly on-line tool. Both versions are available at: http://xerad.systemsbiology.net/simcluster.&#xd;&#xa;&#xd;&#xa;Simcluster is designed in accordance with a well-established mathematical framework for compositional data analysis, which provides principled procedures for dealing with the simplex space, and is thus applicable in a number of contexts, including enumeration-based gene expression data

    Innate immune response is differentially dysregulated between bipolar disease and schizophrenia

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    Articles in PressSchizophrenia (SZ) and bipolar disorder (BD) are severe psychiatric conditions with a neurodevelopmental component. Genetic findings indicate the existence of an overlap in genetic susceptibility across the disorders. Also, image studies provide evidence for a shared neurobiological basis, contributing to a dimensional diagnostic approach. This study aimed to identify the molecular mechanisms that differentiate SZ and BD patients from health controls but also that distinguish both from health individuals. Comparison of gene expression profiling in post-mortem brains of both disorders and health controls (30 cases), followed by a further comparison between 29 BD and 29 SZ revealed 28 differentially expressed genes. These genes were used in co-expression analysesthat revealed the pairs CCR1/SERPINA1, CCR5/HCST, C1QA/CD68, CCR5/S100A11 and SERPINA1/TLR1 as presenting the most significant difference in co-expression between SZ and BD. Next, a protein-protein interaction (PPI) network using the 28 differentially expressed genes as seeds revealed CASP4, TYROBP, CCR1, SERPINA1, CCR5 and C1QA as having a central role in the diseases manifestation. Both co-expression and network topological analyses pointed to genes related to microglia functions. Based on this data, we suggest that differences between SZ and BP are due to genes involved with response to stimulus, defense response, immune system process and response to stress biological processes, all having a role in the communication of environmental factors to the cells and associated to microglia.Stanley Medical Research Institute for providing the tissue samples and the patients for donating the samplesinfo:eu-repo/semantics/publishedVersio
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