20 research outputs found
Determinantes Nacionais e Setoriais da Estrutura de Capital na América Latina
This study identified the role of the national environment (the Macroeconomy, Financial Development and
Institutional Quality) and industry characteristics (Munificence, Dynamism, Concentration, Life Cycle,
Technological Efficiency Dispersion, Product Quality Dispersion, Customer Bargaining Power and Supplier
Bargaining Power) on debt of 612 listed companies from 7 Latin American countries (Argentina, Brazil, Chile,
Colombia, Mexico, Peru and Venezuela). For comparison purposes, the analysis is also extended to 847 U.S.
companies. The period of study is 1996-2009 and the analysis employed a Hierarchical Linear Model, which
controls the effects according to the level of the variables (country, industry, time and firm). The results suggest
that Financial Development eases access to external funds and Institutional Quality is negatively related to firm
Leverage. The research also finds evidence that institutional quality can promote asymmetrical development
between stock markets and credit markets
Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans
Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have
fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in
25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16
regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of
correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP,
while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in
Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium
(LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region.
Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant
enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the
refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa,
an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of
PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent
signals within the same regio
Sedentary behavior in Brazilian children and adolescents: a systematic review
ABSTRACT OBJECTIVE To describe the methodological characteristics of the studies selected and assess variables associated with sedentary behavior in Brazilian children and adolescents. METHODS For this systematic review, we searched four electronic databases: PubMed, Web of Knowledge, LILACS, SciELO. Also, electronic searches were applied in Google Scholar. A supplementary search was conducted in the references lists of the included articles and in non-indexed journals. We included observational studies with children and adolescents aged from three to 19 years developed in Brazil, presenting analyses of associations based on regression methods and published until September 30, 2014. RESULTS Of the 255 potential references retrieved by the searches, 49 met the inclusion criteria and composed the descriptive synthesis. In this set, we identified a great number of cross-sectional studies (n = 43; 88.0%) and high methodological variability on the types of sedentary behavior assessed, measurement tools and cut-off points used. The variables most often associated with sedentary behavior were “high levels of body weight” (in 15 out of 27 studies; 55.0%) and “lower level of physical activity” (in eight out of 16 studies; 50.0%). CONCLUSIONS The findings of this review raise the following demands to the Brazilian agenda of sedentary behavior research geared to children and adolescents: development of longitudinal studies, validation of measuring tools, establishment of risk cut-offs, measurement of sedentary behavior beyond screen time and use of objective measures in addition to questionnaires. In the articles available, the associations between sedentary behavior with “high levels of body weight” and “low levels of physical activity” were observed in different regions of Brazil
Síntese de biodiesel etílico de tungue utilizando catalisadores alcalinos
A grande diversidade de plantas oleaginosas distribuída por todo o território nacional e a auto-suficiência brasileira na produção de etanol, impulsiona a pesquisa de produção de biodiesel etílico. Deste modo, o desenvolvimento de metodologia para a síntese de biodiesel etílico de tungue (Aleuritis fordii) é bastante favorável, pois o cultivo desta oleaginosa se faz em pequenas propriedades rurais, com colheita manual e sem mecanização, inserindo a agricultura familiar no processo de produção de biocombustíveis. Assim, o objetivo deste trabalho foi desenvolver uma metodologia viável para a síntese de biodiesel etílico a partir do óleo de tungue, empregando catalisadores alcalinos convencionais, NaOH e KOH, introduzindo uma melhor separação do biodiesel de seus co-produtos
Síntese de novas Benzilamidas graxas
Amidas graxas são compostos nitrogenados de longas cadeias saturadas ou insaturadas, sintetizadas a partir da condensação entre ácidos graxos provenientes de fontes renováveis e uma amina. As amidas graxas atualmente são descritas na literatura como uma nova família de lipídeos biologicamente ativos. Em estudos recentes, Khan e colaboradores descrevem o isolamento de uma série de benzilamidas graxas a partir do extrato de Lepidium meyenii que apresentaram atividades anticancerígenas, imunoestimulantes e reguladora de desordens sexuais. Recentemente, foram sintetizadas em nosso laboratório pirrolidilamidas graxas que apresentaram atividade citotóxica em células eritroleucêmicas humanas. Dando seguimento às pesquisas de nosso grupo este trabalho propõe a síntese de benzilamidas graxas, ainda inéditas na literatura, a fim de investigar a relação estrutura atividade citotóxica em células de melanoma
Regiospecific synthesis of new fatty N-acyl trihalomethylated pyrazoline derivatives from fatty acid methyl esters (FAMEs)
Uma série de novas pirazolinas N-acil trialometiladas derivadas de ésteres metílicos de
ácidos graxos foi sintetizada por reação de ciclocondensação entre hidrazidas graxas e 4-alcóxi-1,1,1‑trialometil-3-alquen-2-onas. Ciclizações eficientes e regioespecíficas catalisadas por BF3·MeOH levaram aos produtos desejados em rendimentos de bons a excelentes e alto grau de pureza.A series of new fatty N-acyl trihalomethylated pyrazoline derivatives from fatty acid methyl
esters was synthesized by the cyclocondensation of respective fatty hydrazides with 4-alkoxy-1,1,1‑trialomethyl-3-alquen-2-ones. Efficient and regiospecific cyclizations catalyzed by BF3·MeOH gave the desired products in good to excellent yields and at high purity
LAMP2A regulates the loading of proteins into exosomes
International audienceExosomes are extracellular vesicles of endosomal origin that are released by practically all cell types across metazoans. Exosomes are active vehicles of intercellular communication and can transfer lipids, RNAs, and proteins between different cells, tissues, or organs. Here, we describe a mechanism whereby proteins containing a KFERQ motif pentapeptide are loaded into a subpopulation of exosomes in a process that is dependent on the membrane protein LAMP2A. Moreover, we demonstrate that this mechanism is independent of the ESCRT machinery but dependent on HSC70, CD63, Alix, Syntenin-1, Rab31, and ceramides. We show that the master regulator of hypoxia HIF1A is loaded into exosomes by this mechanism to transport hypoxia signaling to normoxic cells. In addition, by tagging fluorescent proteins with KFERQ-like sequences, we were able to follow the interorgan transfer of exosomes. Our findings open new avenues for exosome engineering by allowing the loading of bioactive proteins by tagging them with KFERQ-like motifs
Green Composites from Thiophene Chalcones and Rice Husk Lignin: An Alternative of Powder for Latent Fingermark
This study reports a route to obtaining a novel and cost-effective rice husk-derived lignin/thiophene chalcone green composite for application in forensic science as a fingermark developer through high energy milling. The material was properly characterized by UV-Vis, IR, fluorescence, X-ray diffraction and scanning electron microscopy. The product provided clear and sharp images of latent fingermarks with minimal background staining, revealing all ridge details. Thus, the composite presented good performance as a fingermark developer, becoming an interesting alternative to being applied as a technological, reproducible and renewable product