105 research outputs found
Primeiras evidências sobre os determinantes da duração dos cursos de mestrado em economia no Brasil
The purpose ofthis paper is to determine, using duration models, which characteristics of Economics graduate students affec ttheir probability of concluding their courses. The Kaplan-Meyer estimator pointed out the graduate institution, the undergraduate institution, the entry year, and the relative grade as statistically significant. The Cox model and the parametric model showed that besides the entry year, the relative grade is important for the duration of the Master program. There is, therefore, some indication that it would be important to increase the demand for performance and decrease the length of the courses. It is necessary to observe that this paper constitutes a first at tempt to address the question. Many of the graduate institutions do not have organized data on their students, and this way could not be included in the sample. We hope, however, that the results obtained here stimulate these institutions to gather information on their students and that the estimations could be done again in the fixture using a more representative sample. A better understanding of the subject would allow the different graduate institutions to change their policies, reducing the duration of their courses without loosing quality. The ultimate result would be a better allocation of the resources that are mainly public
Primeiras evidências sobre os determinantes da duração dos cursos de mestrado em economia no Brasil
The purpose ofthis paper is to determine, using duration models, which characteristics of Economics graduate students affec ttheir probability of concluding their courses. The Kaplan-Meyer estimator pointed out the graduate institution, the undergraduate institution, the entry year, and the relative grade as statistically significant. The Cox model and the parametric model showed that besides the entry year, the relative grade is important for the duration of the Master program. There is, therefore, some indication that it would be important to increase the demand for performance and decrease the length of the courses. It is necessary to observe that this paper constitutes a first at tempt to address the question. Many of the graduate institutions do not have organized data on their students, and this way could not be included in the sample. We hope, however, that the results obtained here stimulate these institutions to gather information on their students and that the estimations could be done again in the fixture using a more representative sample. A better understanding of the subject would allow the different graduate institutions to change their policies, reducing the duration of their courses without loosing quality. The ultimate result would be a better allocation of the resources that are mainly public
Comparative study and anticholinesterasic evaluation of essential oils from leaves, stems and flowers of myrciaria floribunda (H.West ex Willd.) O. Berg
Myrciaria floribunda (H.West ex Willd.) O.Berg, Myrtaceae, popularly known as “camboim amarelo”, was collected in Restinga de Jurubatiba (RJ, Brazil). Leaves, stems and flowers were individually submitted to hydrodistillation, affording the respective essential oils. Monoterpenes were the main group of essential oils from leaves (53.9 %) and flowers (55.4 %). Sesquiterpenes were more representative in stems (72.2 %). 1,8-cineole was the major constituent in the essential oil from leaves (38.4 %) and flowers (22.8 %). The major constituent from stems was (2E,6E)-farnesyl acetate (19.9 %). To our knowledge, these are the first contributions for essential oils from stems and flowers of M. floribunda. It was also performed the acetylcholinesterase inhibitory bioassay of the essential oil from stems, flowers and leaves of M.
floribunda. Flowers and leaves oils had an IC50 of 1583 and 681 μg/mL, respectively, being both low to mild values.Colegio de Farmacéuticos de la Provincia de Buenos Aire
TRAF1/C5 but Not PTPRC Variants Are Potential Predictors of Rheumatoid Arthritis Response to Anti-Tumor Necrosis Factor Therapy
Background. The aim of our work was to replicate, in a Southern European population, the association reported in Northern populations between PTPRC locus and response to anti-tumor necrosis factor (anti-TNF) treatment in rheumatoid arthritis (RA). We also looked at associations between five RA risk alleles and treatment response. Methods. We evaluated associations between anti-TNF treatment responses assessed by DAS28 change and by EULAR response at six months in 383 Portuguese patients. Univariate and multivariate linear and logistic regression analyses were performed. In a second step to confirm our findings, we pooled our population with 265 Spanish patients. Results. No association was found between PTPRC rs10919563 allele and anti-TNF treatment response, neither in Portuguese modeling for several clinical variables nor in the overall population combining Portuguese and Spanish patients. The minor allele for RA susceptibility, rs3761847 SNP in TRAF1/C5 region, was associated with a poor response in linear and logistic univariate and multivariate regression analyses. No association was observed with the other allellic variants. Results were confirmed in the pooled analysis. Conclusion. This study did not replicate the association between PTPRC and the response to anti-TNF treatment in our Southern European population. We found that TRAF1/C5 risk RA variants potentially influence anti-TNF treatment response.This work was supported by a grant from Harvard-Portugal Program HMSP-ICS/SAU-ICT/0002/2010. Daniel H. Solomon received support for this work from the NIH (K24-AR-055989). Elizabeth W. Karlson received support for this work from NIH (K24-AR-AR0524). Reuma.pt received unrestricted grants from Abbott, Bristol-Myers Squibb, Merck Sharp and Dohme, Pfizer, Roche, and UCB Pharma
IFNG +874T/A polymorphism is not associated with American tegumentary leishmaniasis susceptibility but can influence Leishmania induced IFN-γ production
<p>Abstract</p> <p>Background</p> <p>Interferon-gamma is a key cytokine in the protective responses against intracellular pathogens. A single nucleotide polymorphism (SNP) located in the first intron of the human IFN-γ gene can putatively influence the secretion of cytokine with an impact on infection outcome as demonstrated for tuberculosis and other complex diseases. Our aim was to investigate the putative association of IFNG+874T/A SNP with American tegumentary leishmaniasis (ATL) and also the influence of this SNP in the secretion of IFN-γ <it>in vitro</it>.</p> <p>Methods</p> <p>Brazilian ATL patients (78 cutaneous, CL, and 58 mucosal leishmaniasis, ML) and 609 healthy volunteers were evaluated. The genotype of +874 region in the IFN-γ gene was carried out by Amplification Refractory Mutational System (ARMS-PCR). <it>Leishmania</it>-induced IFN-γ production on peripheral blood mononuclear cell (PBMC) culture supernatants was assessed by ELISA.</p> <p>Results</p> <p>There are no differences between +874T/A SNP frequency in cases and controls or in ML versus CL patients. Cutaneous leishmaniasis cases exhibiting AA genotype produced lower levels of IFN-γ than TA/TT genotypes. In mucosal cases, high and low IFN-γ producers were clearly demonstrated but no differences in the cytokine production was observed among the IFNG +874T or A carriers.</p> <p>Conclusion</p> <p>Our results suggest that +874T/A polymorphism was not associated with either susceptibility or severity to leishmaniasis. Despite this, IFNG +874T/A SNP could be involved in the pathogenesis of leishmaniasis by influencing the amount of cytokine released by CL patients, although it could not prevent disease development. On the other hand, it is possible that in ML cases, other potential polymorphic regulatory genes such as TNF-α and IL-10 are also involved thus interfering with IFN-γ secretion.</p
Genome of Herbaspirillum seropedicae Strain SmR1, a Specialized Diazotrophic Endophyte of Tropical Grasses
The molecular mechanisms of plant recognition, colonization, and nutrient exchange between diazotrophic endophytes and plants are scarcely known. Herbaspirillum seropedicae is an endophytic bacterium capable of colonizing intercellular spaces of grasses such as rice and sugar cane. The genome of H. seropedicae strain SmR1 was sequenced and annotated by The Paraná State Genome Programme—GENOPAR. The genome is composed of a circular chromosome of 5,513,887 bp and contains a total of 4,804 genes. The genome sequence revealed that H. seropedicae is a highly versatile microorganism with capacity to metabolize a wide range of carbon and nitrogen sources and with possession of four distinct terminal oxidases. The genome contains a multitude of protein secretion systems, including type I, type II, type III, type V, and type VI secretion systems, and type IV pili, suggesting a high potential to interact with host plants. H. seropedicae is able to synthesize indole acetic acid as reflected by the four IAA biosynthetic pathways present. A gene coding for ACC deaminase, which may be involved in modulating the associated plant ethylene-signaling pathway, is also present. Genes for hemagglutinins/hemolysins/adhesins were found and may play a role in plant cell surface adhesion. These features may endow H. seropedicae with the ability to establish an endophytic life-style in a large number of plant species
Pasture characteristics of Italian ryegrass and milk production under different management strategies
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