Programa de Computacao Cientifica

Rio de Janeiro, Brazil

Programa de Computacao Cientifica

Rio de Janeiro, Brazil
Time filter
Source Type

Teixeira T.R.A.,Escola Nacional de Saude Publica Sergio Arouca | Cruz O.G.,Programa de Computacao Cientifica
Cadernos de Saude Publica | Year: 2011

This study analyzed the spatial distribution of dengue in Rio de Janeiro, Brazil, in 2006, and associations between the incidence per 100,000 inhabitants and socio-environmental variables. The study analyzed reported dengue cases amongthe city's inhabitants, rainfall, Breteau index (for Aedes aegypti and Aedes albopictus), Gini index, and social development index. We conductedmapping and used the global Moran index to measure the indicators' spatial autocorrelation,which was positive for all variables. The generalizedlinear model showed a direct association between dengue incidence and rainfall, one-monthrainfall time lag, Gini index, and Breteau indexfor A. albopictus. The conditional autoregressivemodel (CAR) showed a direct association withrainfall for four months of the year, rain time lag in July, and Gini index in February. The resultsdemonstrate the importance of socio-environmentalvariables in the dynamics of dengue transmission and the relevance for the developmentof dengue control strategies.

Villela D.A.M.,Programa de Computacao Cientifica | Garcia G.D.A.,Instituto Oswaldo Cruz | Maciel-de-Freitas R.,Instituto Oswaldo Cruz
PLoS Neglected Tropical Diseases | Year: 2017

Background: Experiments involving mosquito mark-release-recapture (MRR) design are helpful to determine abundance, survival and even recruitment of mosquito populations in the field. Obstacles in mosquito MRR protocols include marking limitations due to small individual size, short lifespan, low efficiency in capturing devices such as traps, and individual removal upon capture. These limitations usually make MRR analysis restricted to only abundance estimation or a combination of abundance and survivorship, and often generate a great degree of uncertainty about the estimations. Methodology/Principal findings: We present a set of Bayesian biodemographic models designed to fit data from most common mosquito recapture experiments. Using both field data and simulations, we consider model features such as capture efficiency, survival rates, removal of individuals due to capturing, and collection of pupae. These models permit estimation of abundance, survivorship of both marked and unmarked mosquitoes, if different, and recruitment rate. We analyze the accuracy of estimates by varying the number of released individuals, abundance, survivorship, and capture efficiency in multiple simulations. These methods can stand capture efficiencies as low as usually reported but their accuracy depends on the number of released mosquitoes, abundance and survivorship. We also show that gathering pupal counts allows estimating differences in survivorship between released mosquitoes and the unmarked population. Conclusion/Significance: These models are important both to reduce uncertainty in evaluating MMR experiments and also to help planning future MRR studies. © 2017 Villela et al.

Lana R.M.,Federal University of Ouro Preto | Carneiro T.G.S.,Federal University of Ouro Preto | Honorio N.A.,Instituto Oswaldo Cruz Fiocruz | Codeco C.T.,Programa de Computacao Cientifica
Acta Tropica | Year: 2013

Mathematical models suggest that seasonal transmission and temporary cross-immunity between serotypes can determine the characteristic multi-year dynamics of dengue fever. Seasonal transmission is attributed to the effect of climate on mosquito abundance and within host virus dynamics. In this study, we validate a set of temperature and density dependent entomological models that are built-in components of most dengue models by fitting them to time series of ovitrap data from three distinct neighborhoods in Rio de Janeiro, Brazil. The results indicate that neighborhoods differ in the strength of the seasonal component and that commonly used models tend to assume more seasonal structure than found in data. Future dengue models should investigate the impact of heterogeneous levels of seasonality on dengue dynamics as it may affect virus maintenance from year to year, as well as the risk of disease outbreaks. © 2013 The Authors.

Suarez-Kurtz G.,Instituto Nacional Of Cancer | Pena S.D.J.,Federal University of Minas Gerais | Struchiner C.J.,Programa de Computacao Cientifica | Hutz M.H.,Federal University of Rio Grande do Sul
Frontiers in Pharmacology | Year: 2012

By virtue of being the product of the genetic admixture of three ancestral roots: Europeans, Africans, and Amerindians, the present-day Brazilian population displays very high levels of genomic diversity, which have important pharmacogenetic/-genomic (PGx) implications. Recognition of this fact has prompted the creation of the Brazilian Pharmacogenomics Network (Refargen), a nationwide consortium of research groups, with the mission to provide leadership in PGx research and education in Brazil, with a population heath impact. Here, we present original data and review published results from a Refargen comprehensive study of the distribution of PGx polymorphisms in a representative cohort of the Brazilian people, comprising 1,034 healthy, unrelated adults, self-identified as white, brown, or black, according to the Color categories adopted by the Brazilian Census. Multinomial log-linear regression analysis was applied to infer the statistical association between allele, genotype, and haplotype distributions among Brazilians (response variables) and self-reported Color, geographical region, and biogeographical ancestry (explanatory variables), whereas Wright's FST statistics was used to assess the extent of PGx divergence among different strata of the Brazilian population. Major PGx implications of these findings are: first, extrapolation of data from relatively well-defined ethnic groups is clearly not applicable to the majority of Brazilians; second, the frequency distribution of polymorphisms in several pharmacogenes of clinical relevance (e.g., ABCB1, CYP3A5, CYP2C9, VKORC) varies continuously among Brazilians and is not captured by race/Color self-identification; third, the intrinsic heterogeneity of the Brazilian population must be acknowledged in the design and interpretation of PGx studies in order to avoid spurious conclusions based on improper matching of study cohorts. © 2012 Suarez-Kurtz, Pena, Struchiner and Hutz.

Perini J.A.,Instituto Nacional Of Cancer | Struchiner C.J.,Programa de Computacao Cientifica | Silva-Assuncao E.,Ambulatorio de Anticoagulacao | Suarez-Kurtz G.,Instituto Nacional Of Cancer
Clinical Pharmacology and Therapeutics | Year: 2010

There is controversy regarding the association between the CYP4F2 rs2108622 (V33M) polymorphism and warfarin dose requirement in white patients, and there are no data for nonwhite populations. We observed no association in self-identified white, black, or intermediate Brazilian patients (n = 370). The addition of the rs2108622 genotype as a variable has only a marginal effect on the predictive power of a warfarin dosing algorithm derived from this patient cohort. We conclude that prospective CYP4F2 genotyping is not justified in Brazilians who are potential candidates for warfarin therapy. © 2010 American Society2010 American Society for Clinical Pharmacology and Therapeutics.

Suarez-Kurtz G.,Instituto Nacional Do Cancer | Paula D.P.,Federal Rural University of Rio de Janeiro | Struchiner C.J.,Programa de Computacao Cientifica
Pharmacogenomics | Year: 2014

The heterogeneous Brazilian population, with European, African and Amerindian ancestral roots is a model case for exploring the impact of population admixture on the frequency distribution of polymorphisms in pharmacogenes, and the design and interpretation of pharmacogenomics trials. Examples drawn from studies carried out by researchers of the Brazilian pharmacogenomics network, support the following conclusions: the distribution of polymorphisms varies across geographical regions and self-reported 'race/color categories, and is best modeled as continuous functions of individual proportions of European and African ancestry; the differential frequency of polymorphisms impacts the calculations of sample sizes required for adequate statistical power in clinical trials performed in different segments of the Brazilian population; and extrapolation of pharmacogenomics data from well-defined ethnic groups to Brazilians is plagued with uncertainty. Data for warfarin and tacrolimus are reviewed to highlight the advantages and challenges of performing pharmacogenomic trials in Brazilians. © 2014 Future Medicine Ltd.

Schechtman H.,Programa de Computacao Cientifica | Souza M.O.,Federal University of Fluminense
PLoS ONE | Year: 2015

Global emergence of arboviruses is a growing public health concern, since most of these diseases have no vaccine or prevention treatment available. In this scenario, vector control through the use of chemical insecticides is one of the most important prevention tools. Nevertheless, their effectiveness has been increasingly compromised by the development of strong resistance observed in field populations, even in spite of fitness costs usually associated to resistance. Using a stage-structured deterministic model parametrised for the Aedes aegypti - the main vector for dengue - we investigated the persistence of resistance by studying the time for a population which displays resistance to insecticide to revert to a susceptible population. By means of a comprehensive series of in-silico experiments, we studied this reversal time as a function of fitness costs and the initial presence of the resistance allele in the population. The resulting map provides both a guiding and a surveillance tool for public health officers to address the resistance situation of field populations. Application to field data from Brazil indicates that reversal can take, in some cases, decades even if fitness costs are not small. As by-products of this investigation, we were able to fit very simple formulas to the reversal times as a function of either cost or initial presence of the resistance allele. In addition, the in-silico experiments also showed that density dependent regulation plays an important role in the dynamics, slowing down the reversal process. © 2015 Schechtman, Souza.

Luz P.M.,Yale University | Luz P.M.,Institute Pesquisa Clinica Evandro Chagas | Struchiner C.J.,Programa de Computacao Cientifica | Galvani A.P.,Yale University
PLoS Neglected Tropical Diseases | Year: 2010

Neglected tropical diseases affect more than one billion people worldwide. The populations most impacted by such diseases are typically the most resource-limited. Mathematical modeling of disease transmission and cost-effectiveness analyses can play a central role in maximizing the utility of limited resources for neglected tropical diseases. We review the contributions that mathematical modeling has made to optimizing intervention strategies of vector-borne neglected diseases. We propose directions forward in the modeling of these diseases, including integrating new knowledge of vector and pathogen ecology, incorporating evolutionary responses to interventions, and expanding the scope of sensitivity analysis in order to achieve robust results. © 2010 Luz et al.

Gandra P.G.,University of Campinas | Valente R.H.,Instituto Oswaldo Cruz | Perales J.,Instituto Oswaldo Cruz | Pacheco A.G.,Programa de Computacao Cientifica | Macedo D.V.,University of Campinas
Scandinavian Journal of Medicine and Science in Sports | Year: 2012

Exercise can alter gene transcriptional and protein translational rates leading to changes in protein abundance toward adaptation to exercise. We investigated the alterations in protein abundance in skeletal muscle after one bout of an exhaustive exercise through proteomic analysis. Gastrocnemius muscles were sampled from non-exercised control rats and from rats exercised on a treadmill with incremental increases in speed until exhaustion (approximately 30min). Rats were sacrificed 3 and 24h after exercise cessation. Two-dimensional gel electrophoresis was performed and spots with a significant alteration in relative volume were identified by mass spectrometry. Six spots presented statistically significant altered abundances after exercise. The spots identified as the metabolic related proteins triosephosphate isomerase 1, glyceraldehyde-3-phosphate dehydrogenase, the β subunit of pyruvate dehydrogenase E 1 and carnitine palmitoyltransferase 2 were all more abundant after exercise. One spot identified as heat shock cognate 70 was also more abundant after exercise. One spot demonstrated a decreased abundance after exercise and was identified as α-actin. These results suggest that a single session of exhaustive incremental exercise in untrained muscle can alter thin filaments synthesis/degradation rate and enhance cytosolic and mitochondrial proteins synthesis. The identified proteins may be important to a general preconditioning of skeletal muscle for subsequent exercise sessions. © 2010 John Wiley & Sons A/S.

Paula A.A.,Programa de Computacao Cientifica | Falcao M.C.N.,Programa de Computacao Cientifica | Pacheco A.G.,Programa de Computacao Cientifica
AIDS Research and Therapy | Year: 2013

The success of highly active antiretroviral therapy (HAART) has determined a dramatic decline in AIDS- and immunodeficiency-related causes of death in the HIV-infected population. As life-expectancy increases, such individuals have become gradually exposed not only to the effects of aging itself, but also to the influence of environmental risk factors, which are known to act in the general population. These features can lead to obesity, diabetes mellitus and ultimately cardiovascular diseases (CVD). Metabolic complications and abnormal fat distribution were frequently observed after a few years of antiretroviral therapy and, as the array of antiretroviral drugs became broader, long term metabolic alterations are becoming far more common worldwide. Nevertheless, the risk of not being on HAART is overwhelmingly greater than the metabolic adverse events in terms of morbidity and mortality events. HIV/HAART-induced metabolic unbalances overlap in some extent the components of Metabolic Syndrome (MetS) and its high rates in the HIV population place infected individuals in an elevated CVD risk category. MetS can explain at least in part the emergence of CVD as the major morbidity and mortality conditions in the HIV population. In this review we convey information on the underlying aspects of MetS during HIV infection, highlighting some physiopathological and epidemiological features of this comorbidity along with the role played by HIV itself and the synergy action of some antiretroviral drugs. Considerations on MetS management in the HIV population are also depicted. © 2013 de Paula et al.; licensee BioMed Central Ltd.

Loading Programa de Computacao Cientifica collaborators
Loading Programa de Computacao Cientifica collaborators