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1.
Arq. bras. med. vet. zootec. (Online) ; 73(6): 1391-1402, Nov.-Dec. 2021. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1355689

ABSTRACT

This study was carried out for two purposes: comparing performances of Regression Tree and Automatic Linear Modeling and determining optimum sample size for these methods under different experimental conditions. A comprehensive Monte Carlo Simulation Study was designed for these purposes. Results of simulation study showed that percentage of explained variation estimates of both Regression Tree and Automatic Linear Modeling was influenced by sample size, number of variables, and structure of variance-covariance matrix. Automatic Linear Modeling had higher performance than Regression Tree under all experimental conditions. It was concluded that the Regression Tree required much larger samples to make stable estimates when comparing to Automatic Linear Modeling.(AU)


Este estudo foi realizado com dois objetivos: comparar os desempenhos da Árvore de Regressão e da Modelagem Linear Automática e determinar o tamanho ideal da amostra para estes métodos sob diferentes condições experimentais. Um abrangente Estudo de Simulação de Monte Carlo foi projetado para estes propósitos. Os resultados do estudo de simulação mostraram que a porcentagem de estimativas de variação explicada tanto da Árvore de Regressão como da Modelagem Linear Automática foi influenciada pelo tamanho da amostra, número de variáveis e estrutura da matriz de variância-covariância. A Modelagem Linear Automática teve um desempenho superior ao da Árvore de Regressão em todas as condições experimentais. Concluiu-se que a Árvore de Regressão exigia amostras muito maiores para fazer estimativas estáveis quando comparada à Modelagem Linear Automática.(AU)


Subject(s)
Linear Models , Monte Carlo Method , Regression Analysis , Data Analysis , Simulation Technique/methods
2.
Rev. bras. ciênc. vet ; 28(2): 75-80, abr./jun. 2021. il.
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1367182

ABSTRACT

O objetivo deste trabalho foi avaliar a eficácia do florfenicol na dose usualmente empregada em equinos de 22 mg/kg pelas vias intravenosa, intramuscular e oral para o tratamento de adenite equina por Streptococcus equi. subsp. equi, usando a modelagem farmacocinética/farmacodinâmica (PK/PD ­ Pharmacokinetic/Pharmacodynamic) e a simulação de Monte Carlo. Foi realizada uma simulação de Monte Carlo a partir dos parâmetros PK, logo depois, efetuou-se a modelagem PK/PD para determinar as taxas de eficácia do antimicrobiano para o tratamento dessa infecção bacteriana, de acordo com o valor da concentração inibitória mínima (CIM), em um intervalo de CIM de 0,125 ­ 4 µg/mL. Pela via intravenosa, a probabilidade de erradicação bacteriana foi de 100% para CIM até 0,5 µg/mL e efeito bacteriostático com probabilidades de 99% e 80% para CIMs de 2 e 4 µg/mL, respectivamente. Já pelas vias intramuscular e oral a probabilidade de se atingir o índice de erradicação bacteriológica foi de 100% para CIM de até 0,5 µg/mL, contudo, atinge valores de 80% e 81%, respectivamente, para CIM de 1 µg/mL considerando o efeito bactericida (p<0,01). Portanto, através desse estudo é evidenciado a eficácia do florfenicol até a CIM de 0,5 µg/mL para as três vias de administração citadas, entretanto, para CIMs superiores a esse valor, é imprescindível o ajuste da dose farmacológica, evitando falhas na terapêutica e possível resistência microbiana.


The objective of this study was to evaluate the efficacy of florfenicol at the dose usually used in horses of 22 mg/kg by intravenous, intramuscular and oral routes for the treatment of equine adenitis caused by Streptococcus equi. subsp. equi, using Pharmacokinetic/Pharmacodynamic (PK/PD) modeling and Monte Carlo simulation. A Monte Carlo simulation was performed from the PK parameters, then PK/PD modeling was performed to determine the antimicrobial efficacy rates for the treatment of this bacterial infection, according to the minimum inhibitory concentration (MIC) value, in a MIC range of 0.125 - 4 µg/mL. Intravenously, the probability of bacterial eradication was 100% for MICs up to 0.5 µg/mL, and the bacteriostatic effect was 99% and 80% for MICs of 2 and 4 µg/mL, respectively. However, for the intramuscular and oral routes, the probability of reaching the bacteriologic eradication index was 100% for MICs of up to 0.5 µg/mL, however, it reaches values of 80% and 81%, respectively, for MICs of 1 µg/mL considering the bactericidal effect (p<0.01). Therefore, through this study the efficacy of florfenicol is evidenced up to the MIC of 0.5 µg/mL for the three routes of administration cited, however, for MICs higher than this value, it is essential to adjust the pharmacological dose, avoiding failures in therapy and possible microbial resistance.


Subject(s)
Animals , Horse Diseases/therapy , Lymphadenitis/veterinary , Anti-Bacterial Agents/therapeutic use , Pharmacokinetics , Monte Carlo Method
3.
São Paulo; s.n; 2021. 124 p.
Thesis in Portuguese | LILACS | ID: biblio-1291350

ABSTRACT

Introdução: Arroz pode ser a principal fonte de exposição a arsênio inorgânico (iAs), que é carcinogênico e está associado a diversos efeitos não-carcinogênicos. Produtos feitos de arroz, como cereais infantis, e água para consumo podem ser importantes fontes de exposição a iAs. Embora o arroz seja um componente básico da dieta da população brasileira, há poucos estudos avaliando os riscos à saúde decorrentes da exposição ao iAs. Objetivo: Avaliar o risco da exposição a iAs e/ou outros elementos tóxicos e essenciais em arroz integral, arroz branco, cereais infantis, e água potável no Brasil, e identificar possíveis medidas para mitigar o risco. Método: O incremento de risco de câncer no tempo de vida (ILCR), o risco não-carcinogênico (HQ) e o hazard Index (HI) foram estimados através de análise probabilística com simulações de Monte Carlo. A concentração de elementos em arroz e cereais infantis foi obtida de pesquisas realizadas no Brasil, e a concentração de arsênio em água provém do monitoramento nacional de vigilância da qualidade da água. Resultados e discussão: O ILCR médio para exposição a iAs em arroz branco foi 1.3 × 10-04, arroz integral 5.4 × 10-06, e para exposição a chumbo (Pb) em arroz integral foi 2.5 x 10-8. O HQ para arroz foi estimado abaixo de 1 para todos os elementos, assim como o HI, sugerindo que efeitos não carcinogênicos não são esperados. O ILCR médio decorrente da exposição a iAs em água foi 6.5 × 10-05, acima do limite de 1 × 10-5, e o HQ foi inferior a 1. Cereais infantis feitos de arroz foram o tipo de cereal com maior ILCR (4.0 x 10-5) e com mais elementos com HQ acima de 1. Todos os cereais infantis apresentaram HQ acima de 1 para ao menos um elemento. Cadmio foi o elemento tóxico mais significativo, e zinco o elemento essencial mais relevante. Estimou-se que através de ações de mitigação o risco carcinogênico devido ao consumo de arroz poderia ser reduzido em até 68%, e para cereais infantis em 24%. O ILCR para arroz foi considerado elevado, ainda que as concentrações de iAs estejam dentro dos limites permitidos. O risco para arroz integral foi menor que para arroz branco, devido à baixa concentração de iAs nas amostras avaliadas, e as possíveis razões para isto foram exploradas, como o local do cultivo, práticas agrícolas e o tipo de cultivar de arroz. O risco carcinogênico e não-carcinogênico referente a exposição a Pb foi considerado baixo, entretanto nenhum nível de exposição a este elemento é considerado seguro. Conclusões: O ILCR para consumo de arroz, cereal infantil e água foi considerado elevado. O risco não-carcinogênico foi considerado elevado apenas para cereais infantis, incluindo elementos tóxicos e essenciais, e cereais infantis feitos de arroz apresentaram risco mais significativo. O consumo de água representou um menor risco carcinogênico, entretanto considerado não tolerável. Com o suporte de políticas públicas, medidas para reduzir os riscos relativos ao consumo de arroz e cereais infantis poderiam ter um impacto positivo para a saúde pública no Brasil.


Introduction: Rice can be the main source of exposure to inorganic arsenic (iAs), which is classified as carcinogenic and is also associated with non-cancer effects. Rice products, such as infant cereals, and drinking water are also important sources of exposure to iAs. Although rice is a staple food in Brazil, there have been few studies about the health risks for the Brazilian population. Objective: The objective of this study was to assess the risks of exposure to iAs and other toxic and essential elements from brown rice, white rice (only iAs), infant cereal (made of rice and different raw materials), and drinking water (only iAs) in Brazil, and to identify possible measures to mitigate those risks. Method: The incremental lifetime cancer risk (ILCR) and the non-cancer risk, or hazard quotient (HQ), and hazard index (HI) were calculated. A probabilistic analysis was performed with Monte Carlo simulation. Results and discussion: The mean ILCR was 1.3 × 10-04 for exposure to iAs in white rice and 5.4 × 10-06 for brown rice, and for exposure to Pb it was 2.5 x 10-8 for brown rice. The HQ was under 1 for all elements in brown rice, as the HI, suggesting that health effects are unlikely. The mean ILCR for exposure to iAs from drinking water was 6.5 × 10-05, above the tolerable value of 1 × 10-5 recommended by the World Health Organization, and the HQ was below 1. Rice cereal was the kind of infant cereal with highest ILCR (4.0 x 10-5) and with more elements with HQ above 1. All the infant cereals had an HQ above 1 for at least one element. Cd was the non-essential element more significative in this scenario, and Zn was the essential element more relevant. Various mitigation measures discussed in this dissertation are estimated to reduce the risk from rice consumption by 68%, and from infant cereal by 24%. The ILCR for white and brown rice was high, even though the iAs concentration in rice is below the maximum contaminant level. The risk for brown rice consumption was lower because the iAs concentrations were low in the brown rice samples evaluated, which possible reasons were explored, such as the location of cultivation, agricultural practices and the kind of rice cultivar. The estimated cancer and non-cancer risk from exposure to Pb is low, however no exposure to this element from diet is considered safe. Conclusions: The ILCR for rice, infant cereal and water consumption was considered high. The non-cancer risk was not tolerable only for infant cereal, including essential and non-essential elements, and rice cereal showed to be more concerning. Water consumption represents a small part of the risk for adults, although it was estimated to be not tolerable. With the support of public policies, measures to reduce these risks from rice and infant cereal would have a positive impact on public health in Brazil.


Subject(s)
Drinking Water , Monte Carlo Method , Staple Food , Risk Evaluation and Mitigation , Infant Food , Lead , Arsenic , Public Policy , Oryza
5.
Medicina (B.Aires) ; 80(1): 31-38, feb. 2020. ilus, graf, tab
Article in Spanish | LILACS | ID: biblio-1125035

ABSTRACT

Un modelo estocástico de simulación permite estudiar y represen tar de manera simplificada el comportamiento de variables complejas en términos de probabilidad. En este contexto, el objetivo de este trabajo es presentar, a través del uso de herramientas de tecnologías de la información y comunicación, la aplicabilidad de modelos y métodos de simulación, en estudios de indicadores dentro del sector de la salud. A través del desarrollo de un caso de estudio, este trabajo demuestra el potencial de las herramientas tecnológicas @Risk y Excel en la construcción de modelos estocásticos que permiten a los profesionales de la salud predecir, monitorizar y dar soporte en la toma de decisiones en el tratamiento y seguimiento de indicadores e índices de una población.


A stochastic simulation model allows to study and represents in a simplified manner the behavior of complex variables in terms of probability. In this context, the objective of this work is to present, through the use of information and communication technology tools, the applicability of simulation models and methods, in studies of indicators within the health sector. Through the development of a case study, this work demonstrates the potential of the @Risk and Excel technological tools in the construction of stochastic models that allow health professionals to predict, monitor and support decision making in the treatment and monitoring of indicators and indices of a population.


Subject(s)
Humans , Female , Infant, Newborn , Infant , Child, Preschool , Probability , Stochastic Processes , Information Technology/statistics & numerical data , Health Communication , Health Information Systems/statistics & numerical data , Body Mass Index , Sex Factors , Monte Carlo Method , Reproducibility of Results , Age Factors , Ecuador/epidemiology , Obesity/epidemiology
6.
Arq. bras. cardiol ; 114(2): 199-206, Feb. 2020. tab, graf
Article in English | LILACS | ID: biblio-1088856

ABSTRACT

Abstract Background: In many cities around the world, the mortality rate from cancer (CA) has exceeded that from disease of the circulatory system (DCS). Objectives: To compare the mortality curves from DCS and CA in the most populous capital cities of the five regions of Brazil. Methods: Data of mortality rates from DCS and CA between 2000 and 2015 were collected from the Mortality Information System of Manaus, Salvador, Goiania, Sao Paulo and Curitiba, and categorized by age range into early (30-69 years) and late (≥ 70 years), and by gender of the individuals. Chapters II and IX of the International Classification of Diseases-10 were used for the analysis of causes of deaths. The Joinpoint regression model was used to assess the tendency of the estimated annual percentage change of mortality rate, and the Monte Carlo permutation test was used to detect when changes occurred. Statistical significance was set at 5%. Results: There was a consistent decrease in early and late mortality from DCS in both genders in the cities studied, except for late mortality in men in Manaus. There was a tendency of decrease of mortality rates from CA in São Paulo and Curitiba, and of increase in the rates from CA in Goiania. In Salvador, there was a decrease in early mortality from CA in men and women and an increase in late mortality in both genders. Conclusion: There was a progressive and marked decrease in the mortality rate from DCS and a maintenance or slight increase in CA mortality in the five capital cities studied. These phenomena may lead to the intersection of the curves, with predominance of mortality from CA (old and new cases).


Resumo Fundamento: Em muitas cidades no mundo, a taxa de mortalidade por câncer (CA) ultrapassou aquela por doenças do aparelho circulatório (DAC). Objetivos: Comparar as curvas de mortalidade por DAC e CA nas capitais mais populosas das cinco regiões brasileiras. Métodos: Dados de mortalidade por DAC e CA entre 2000 e 2015 foram coletadas no Sistema de Informações sobre Mortalidade das capitais mais populosas das cinco regiões do Brasil: Manaus, Salvador, Goiânia, São Paulo e Curitiba. Os dados foram categorizados por faixas etárias dos indivíduos em precoce (30-69 anos) e tardia (≥70 anos), e por gênero. Foram considerados os capítulos II e IX da Classificação Internacional de Doenças-10 para análise das causas de óbito. A tendência na estimativa de mudança percentual foi calculada pelo modelo de regressão Joinpoint 4.6.0.0. e a detecção das mudanças das taxas pelo teste de permutação Monte Carlo. Nível de significância estatística de 5%. Resultados: Observou-se queda consistente das mortalidades precoce e tardia por DAC, em ambos os gêneros, nas capitais estudadas, com exceção da mortalidade tardia em homens em Manaus. Houve tendência de queda das taxas de mortalidade por CA em São Paulo e Curitiba, e de aumento da taxa de mortalidade por CA em Goiânia. Em Salvador, houve queda na mortalidade precoce por CA em homens e mulheres e incremento na mortalidade tardia em ambos os gêneros. Conclusão: Houve queda progressiva e expressiva da taxa de mortalidade por DAC nas cinco capitais em oposição à manutenção ou discreta elevação da mortalidade por CA. Tais fenômenos concorrem para o cruzamento das curvas com predomínio da mortalidade por CA (já ocorrido ou casos novos).


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Cardiovascular Diseases/mortality , Mortality/trends , Neoplasms/mortality , Time Factors , Brazil/epidemiology , Sex Factors , Monte Carlo Method , Cause of Death/trends , Age Factors , Cities/epidemiology , Sex Distribution , Age Distribution
7.
Rev. bras. epidemiol ; 23: e200041, 2020. tab, graf
Article in English | LILACS | ID: biblio-1101601

ABSTRACT

ABSTRACT: Introduction: Brazil has registered more than 62,000 confirmed cases of leptospirosis between 2001 and 2017, with more than 2,000 cases confirmed in the State of Pará. Despite a large number of cases, no study has been conducted to trace the spatio-temporal profile of the disease. Methodology: Confirmed cases of leptospirosis from 2001 to 2017 from the state of Pará were the basis for this space-time study. The database of the Department of Informatics of the Ministry of Health was used to access data on leptospirosis. The spatio-temporal analysis was performed in the SaTScan software for the detection of clusters, and maps were generated in the QGIS software. Results: The municipalities of Belém and Santarém were among the ones with the highest incidence rates of leptospirosis for the whole study period. Increased number of cases in Soure, Inhangapi, São João da Ponta and Magalhães Barata, Ponta de Pedras, Breves, Bragança, Castanhal, and São Domingos do Capim were identified in different time periods. Santarém and Belém are the main foci of leptospirosis because they are the most urbanized and densely populated municipalities in the State. The cases found in smaller municipalities may be associated with periods of more frequent rainfall and circulation of Leptospira sp. in marsupials and cattle, in the northeastern part of the State. Conclusion: Further studies are needed to help identify the risk factors that contribute to the occurrence of leptospirosis in the State of Pará, particularly in areas with lower population density.


RESUMO: Introdução: O Brasil registrou mais de 62 mil casos de leptospirose confirmados entre 2001 e 2017, com mais de 2.000 casos confirmados no estado do Pará. Apesar da grande quantidade de casos, nenhum estudo até este momento traçou o perfil espaço-temporal da doença. Metodologia: Este é um estudo espaço-temporal com base nos casos confirmados de leptospirose entre 2001 a 2017 no estado do Pará. O banco de dados do Departamento de Informática do Ministério da Saúde foi utilizado para acessar os dados de leptospirose. A análise espaço-temporal foi realizada no software SaTScan para detecção de clusters e os mapas foram gerados no software QGIS. Resultados: O município de Belém e Santarém se mantiveram entre as maiores taxas de incidência de leptospirose durante todo o período estudado. O aumento no número de casos em Soure, Inhangapi, São João da Ponta e Magalhães Barata, Ponta de Pedras, Breves, Bragança, Castanhal e São Domingos do Capim foram identificados em diferentes períodos. Santarém e Belém são os principais focos de leptospirose por serem os municípios mais urbanizados e com maior densidade populacional do estado. Os casos observados em municípios menores podem estar associados a períodos de maior pluviosidade e circulação de Leptospira sp. em marsupiais e em gado no nordeste do estado. Conclusão: Com o exposto, torna-se necessário mais estudos visando o conhecimento dos fatores que contribuem com a ocorrência da leptospirose no estado do Pará, particularmente em áreas com menor adensamento populacional.


Subject(s)
Humans , Male , Female , Infant, Newborn , Child, Preschool , Child , Adolescent , Adult , Young Adult , Leptospirosis/epidemiology , Rural Population , Time Factors , Urban Population , Brazil/epidemiology , Monte Carlo Method , Retrospective Studies , Risk Factors , Cities , Sex Distribution , Age Distribution , Risk Assessment , Spatio-Temporal Analysis , Geography , Middle Aged
8.
Article in Chinese | WPRIM | ID: wpr-828868

ABSTRACT

OBJECTIVE@#To explore the relationship between sample size in the groups and statistical power of ANOVA and Kruskal-Wallis test with an imbalanced design.@*METHODS@#The sample sizes of the two tests were estimated by SAS program with given parameter settings, and Monte Carlo simulation was used to examine the changes in power when the total sample size varied or remained fixed.@*RESULTS@#In ANOVA, when the total sample size was fixed, increasing the sample size in the group with a larger mean square error improved the statistical power, but an excessively large difference in the sample sizes between groups led to reduced power. When the total sample size was not fixed, a larger mean square error in the group with increased sample size was associated with a greater increase of the statistical power. In Kruskal-wallis test, when the total sample size was fixed, increasing the sample size in groups with large mean square errors increased the statistical power irrespective of the sample size difference between the groups; when total sample size was not fixed, a larger mean square error in the group with increased sample size resulted in an increased statistical power, and the increment was similar to that for a fixed total sample size.@*CONCLUSIONS@#The relationship between statistical power and sample size in groups is affected by the mean square error, and increasing the sample size in a group with a large mean square error increases the statistical power. In Kruskal-Wallis test, increasing the sample size in a group with a large mean square error is more cost- effective than increasing the total sample size to improve the statistical power.


Subject(s)
Computer Simulation , Models, Statistical , Monte Carlo Method , Sample Size
9.
Epidemiol. serv. saúde ; 29(5): e2020361, 2020. tab, graf
Article in English, Portuguese | ColecionaSUS, LILACS, ColecionaSUS, SES-SP | ID: biblio-1142934

ABSTRACT

Objetivo: Construir cenários e analisar o impacto das políticas de distanciamento social na propagação da COVID-19 e a necessidade de leitos de unidades de terapia intensiva (UTI). Métodos: Sobre modelo compartimental de transição dinâmica e simulações de Monte Carlo, construíram-se três cenários de propagação conforme o nível de adesão às medidas de distanciamento social no Distrito Federal, Brasil. Os valores dos parâmetros do modelo fundamentaram-se em fontes oficiais, bases com indexação bibliográfica e repositórios públicos de dados. Resultados: O cenário favorável, com manutenção constante de 58% de adesão ao distanciamento social, estimou pico de 189 (intervalo interquartil [IIQ]: 57 a 394) internações-UTI em 7/3/2021. A ausência do distanciamento implicaria grave cenário, com pico de 6.214 (IIQ: 4.618 a 8.415) internações-UTI já na data provável de 14/7/2020. Conclusão: as projeções indicam alto impacto das medidas de distanciamento social e reforçam a aplicabilidade de indicadores públicos no monitoramento da COVID-19.


Objetivo: Construir escenarios y analizar el impacto de las políticas de distanciamiento social en la propagación de Covid-19 y la necesidad de camas en unidades de cuidados intensivos (UCI). Métodos: Con un modelo compartimental de transición dinámica y simulaciones de Monte Carlo, los escenarios de propagación se construyeron de acuerdo al nivel de adhesión de las medidas de distanciamiento social en el Distrito Federal, Brasil. Los parámetros se basaron en fuentes oficiales, bases de datos indexadas y repositorios de datos. Resultados: La adhesión al nivel de distanciamiento social con manutención constante de 58% fue el único escenario favorable, con un pico de 189 (intervalo intercuartil IIC: 57 a 394) admisiones en la UCI el 7/3/2021. La ausencia de distanciamiento implicaría en grave escenario, con un pico de 6.214 (IIC: 4.618 a 8.415) admisiones en UCI ya en la fecha probable de 14/7/2020. Conclusión: Las proyecciones muestran el alto impacto de las medidas de distanciamiento social y la aplicabilidad de indicadores públicos en el monitoreo.


Objective: To build scenarios and analyze the impact of social distancing policies on the spread of COVID-19 and the need for intensive care unit beds. Methods: Three dissemination scenarios were built according to level of adherence to social distancing measures in the context of Brazil's Federal District, based on a dynamic transition compartmental model and Monte Carlo simulations. The model's parameter values were based on official sources, indexed bibliographic databases and public data repositories. Results: The favorable scenario, with constant 58% adherence to social distancing, estimated a peak of 189 (interquartile range [IQR]: 57 - 394) ICU hospitalizations on March 3rd2021. Absence of social distancing would result in an unfavorable scenario with a peak of 6,214 (IQR: 4,618 - 8,415) ICU hospitalizations probably as soon as July 14th2020. Conclusion: The projections indicate the high impact of social distancing measures and emphasize the applicability of public indicators for COVID-19 monitoring.


Subject(s)
Bed Occupancy/statistics & numerical data , Coronavirus Infections/therapy , Coronavirus Infections/epidemiology , Hospitalization/statistics & numerical data , Intensive Care Units/statistics & numerical data , Patient Isolation , Brazil/epidemiology , Monte Carlo Method , Critical Care/statistics & numerical data , Forecasting/methods
10.
Rev. chil. radiol ; 25(3): 94-102, oct. 2019. tab, ilus
Article in Spanish | LILACS | ID: biblio-1058206

ABSTRACT

Resumen: Se presenta una aplicación basada en Microsoft Excel llamada Xpektrin para el cálculo de dosis en radiología general. La aplicación permite simular espectros de rayos X en radiología general utilizando el modelo TASMICS a partir de mediciones del kerma en aire (Kair) y de la capa Hemirreductora (HVL). Tiene implementado el cálculo de magnitudes radiométricas y dosimétricas, como el kerma en aire en la superficie de entrada (Ke) y la dosis en piel (Dskin), en función de la elección arbitraria de los factores de exposición, el tipo y grosor de filtro, la distancia foco-piel y el tamaño de campo. Xpektrin fue validado con la herramienta computacional SPEKTR 3.0, utilizando mediciones de dosis y de HVL de tubos de rayos X de tres recintos hospitalarios. Se encontró buena correlación en ambas aplicaciones entre las mediciones experimentales y los valores calculados de HVL y con coeficientes de Pearson R² ≥ 0.99 en todos los casos. Sin embargo, se obtuvo mejor concordancia con los valores experimentales de HVL con Xpektrin (mediana de diferencias -0.43%, -0.04% y 0.01%) que con SPEKTR 3.0 (mediana de diferencias -3.31%, 0.10% y -7.85%), en particular para el tubo con mayor filtración. Xpektrin está optimizada para ser utilizada en los departamentos de radiología para la determinación de dosis de pacientes individuales en función de los parámetros utilizados durante la exposición, por lo que puede ser utilizada como parte de un sistema de registro dosimétrico o como apoyo para el establecimiento de niveles de referencia para diagnóstico (NRD), siendo particularmente útil en servicios con equipos sin registros automáticos de dosis. Además, debido a sus características de simulador, puede ser útil como herramienta pedagógica. El uso de Excel permite que sea altamente distribuible y fácil de usar, sin necesidad de conocimientos de programación.


Abstract: Xpektrin, an easy to use and highly distributable X-Ray Spectra Simulator in General Radiography. An application based on Microsoft Excel called Xpektrin is presented for dose calculation in general radiology. The application was developed to simulate X-ray spectra in general radiography using the TASMICS model. Using as inputs air kerma (Kair) and Half-value layer (HVL) measurements, Xpektrin allows the calculation of several radiometric and dosimetric quantities, such as the entrance surface air kerma (Ke) and the skin dose (Dskin), depending on the exposure factors, filter material type, filter thickness, focus-skin distance and field size. Xpektrin was validated against the Matlab toolkit SPEKTR 3.0, using dose and HVL measurements of X-ray tubes from three different hospitals. It was found good correlation in both applications between the experimental measurements and the calculated HVL and Kair values with Pearson coefficients R² ≥ 0.99 in all cases. However, experimental and calculated HVL have better agreement with Xpektrin (median percent difference -0.43%, -0.04% and 0.01%) than SPEKTR 3.0 (median percent difference -3.31%, 0.10% and -7.85%), particularly for the tube with greater filtration thickness. Xpektrin is optimized to be used in radiology departments for patient dose determination depending on the exposure parameters and may be used as part of a dosimetric record system or as a support for the determination of Diagnostic Reference Levels, which may be useful when no automatic dose records are available. In addition, due to its simulator characteristics, it can be useful as a pedagogical tool. Using Excel allows Xpektrin to be highly distributable and easy to use, without the need for programming skills.


Subject(s)
Humans , Radiology/methods , Spectrometry, X-Ray Emission/methods , Computer Simulation , Spectrometry, X-Ray Emission/standards , Software , Monte Carlo Method , Diagnostic Reference Levels
11.
Electron. j. biotechnol ; 40: 78-83, July. 2019. tab, graf, ilus
Article in English | LILACS | ID: biblio-1053493

ABSTRACT

Background: Mathematical modeling is useful in the analysis, prediction, and optimization of an enzymatic process. Unlike the conventional modeling methods, Monte Carlo method has special advantages in providing representations of the molecule's spatial distribution. However, thus far, Monte Carlo modeling of enzymatic system is namely based on unimolecular basis, not suitable for practical applications. In this research, Monte Carlo modeling is performed for enzymatic hydrolysis of lactose for the purpose of real-time applications. Results: The enzyme hydrolysis of lactose, which is conformed to Michaelis­Menten kinetics, is modeled using the Monte Carlo modeling method, and the simulation results prove that the model predicts the reaction kinetics very well. Conclusions: Monte Carlo modeling method can be used to model enzymatic reactions in a simple way for real-time applications.


Subject(s)
Monte Carlo Method , Enzymes/metabolism , Hydrolysis , Lactose/metabolism , Time Factors , Kinetics , beta-Galactosidase/metabolism , Enzymes, Immobilized , Galactose/metabolism
12.
Rev. bras. enferm ; 72(3): 617-623, May.-Jun. 2019. tab, graf
Article in English | LILACS, BDENF | ID: biblio-1013549

ABSTRACT

ABSTRACT Objective: To analyze cost-effectiveness and to calculate incremental cost-effectiveness ratio of the use of infusion pumps with drug library to reduce errors in intravenous drug administration in pediatric and neonatal patients in Intensive Care Units. Methods: Mathematical modeling for economic analysis of the decision tree type. The base case was composed of reference and alternative settings. The target population was neonates and pediatric patients hospitalized in Pediatric and Neonatal Intensive Care Units, comprising a cohort of 15,034 patients. The cost estimate was based on the bottom-up and top-down approaches. Results: The decision tree, after RollBack, showed that the infusion pump with drug library may be the best strategy to avoid errors in intravenous drugs administration. Conclusion: The analysis revealed that the conventional pump, although it has the lowest cost, also has lower effectiveness.


RESUMEN Objetivo: Analizar el costo-efectividad y calcular la razón de costo-efectividad incremental del uso de bombas de infusión con una biblioteca de fármacos para reducir errores en la administración de medicamentos por vía intravenosa, en pacientes pediátricos y neonatales en unidades de terapia intensiva. Método: Modelaje matemático para el análisis económico, del tipo árbol de decisión. El caso base se compone de escenarios de referencia y alternativo. La población objetivo fueron pacientes neonatos y pediátricos internados en unidades de terapia intensiva pediátrica y neonatal, componiendo una cohorte de 15.034 pacientes. La estimación de costos se basó en los enfoques bottom-up y top-down. Resultados: El árbol de decisión, después de Roll Back, mostró que la bomba de infusión con biblioteca de fármacos puede ser la mejor estrategia para evitar errores en la administración de medicamentos intravenosos. Conclusión: El análisis reveló que la bomba convencional, aunque tiene el menor costo, tiene también menor efectividad.


RESUMO Objetivo: Analisar o custo-efetividade e calcular a razão de custo-efetividade incremental do uso de bombas de infusão com biblioteca de fármacos para reduzir erros na administração de medicamento pela via intravenosa, em pacientes pediátricos e neonatais em Unidades de Terapia Intensiva. Método: Modelagem matemática para análise econômica, do tipo árvore de decisão. O caso-base foi composto pelos cenários de referência e alternativo. A população alvo foram pacientes neonatos e pediátricos internados em Unidades de Terapia Intensiva pediátrica e neonatal, compondo uma coorte de 15.034 pacientes. A estimativa de custos foi baseada nas abordagens bottom-up e top-down. Resultados: A árvore de decisão, após RollBack, mostrou que a bomba de infusão com biblioteca de fármacos pode ser a melhor estratégia para evitar erros na administração de medicamentos intravenosos. Conclusão: A análise revelou que a bomba convencional, embora tenha o menor custo, tem também menor efetividade.


Subject(s)
Humans , Infant, Newborn , Infusion Pumps/economics , Infusion Pumps/standards , Medication Errors/prevention & control , Technology Assessment, Biomedical/methods , Brazil , Intensive Care Units, Pediatric/organization & administration , Intensive Care Units, Pediatric/statistics & numerical data , Intensive Care Units, Neonatal/organization & administration , Intensive Care Units, Neonatal/statistics & numerical data , Monte Carlo Method , Cost-Benefit Analysis , Administration, Intravenous/methods , Administration, Intravenous/standards , Medication Errors/economics , Medication Errors/nursing
13.
Article in Chinese | WPRIM | ID: wpr-774161

ABSTRACT

The deoxyribonucleic acid (DNA) molecule damage simulations with an atom level geometric model use the traversal algorithm that has the disadvantages of quite time-consuming, slow convergence and high-performance computer requirement. Therefore, this work presents a density-based spatial clustering of applications with noise (DBSCAN) clustering algorithm based on the spatial distributions of energy depositions and hydroxyl radicals (·OH). The algorithm with probability and statistics can quickly get the DNA strand break yields and help to study the variation pattern of the clustered DNA damage. Firstly, we simulated the transportation of protons and secondary particles through the nucleus, as well as the ionization and excitation of water molecules by using Geant4-DNA that is the Monte Carlo simulation toolkit for radiobiology, and got the distributions of energy depositions and hydroxyl radicals. Then we used the damage probability functions to get the spatial distribution dataset of DNA damage points in a simplified geometric model. The DBSCAN clustering algorithm based on damage points density was used to determine the single-strand break (SSB) yield and double-strand break (DSB) yield. Finally, we analyzed the DNA strand break yield variation trend with particle linear energy transfer (LET) and summarized the variation pattern of damage clusters. The simulation results show that the new algorithm has a faster simulation speed than the traversal algorithm and a good precision result. The simulation results have consistency when compared to other experiments and simulations. This work achieves more precise information on clustered DNA damage induced by proton radiation at the molecular level with high speed, so that it provides an essential and powerful research method for the study of radiation biological damage mechanism.


Subject(s)
Algorithms , Computer Simulation , DNA , Radiation Effects , DNA Damage , Linear Energy Transfer , Monte Carlo Method , Protons
14.
Arq. neuropsiquiatr ; 76(3): 150-157, Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-888362

ABSTRACT

ABSTRACT Objective The main goal of this study was to correlate migraine improvement, after prophylactic therapy, with cortical thickness changes. Methods Cortical thickness maps were obtained with magnetic resonance imaging (MRI) from 19 patients with migraine before (first scan) and after (second scan) prophylactic treatment, and these were compared with controls using the FreeSurfer MRI tool. Cortical changes were correlated with the headache index (HI). Results Anincrease incortical thickness was found in the right cuneus and precuneus, somatosensory and superior parietal cortices in both patient scans, compared with the controls. No changes were observed in the left hemisphere. Following correction for multiple comparisons, no areas changed from the first to the second scan. Regression analysis showed a significant negative correlation between the HI improvement and cortical thickness changes in the left posterior cingulate, a region involved with nociception and, possibly, the development of chronic pain. Conclusion There were changes in cortical thickness in patients with migraine relative to controls in areas involved with vision and pain processing. Left posterior cingulate cortical changes correlated with headache frequency and intensity.


RESUMO Objetivos Correlacionar a melhora de pacientes enxaquecosos após tratamento preventivo com alterações na espessura do córtex cerebral. Métodos Espessura cortical foi determinada a partir de imagens de ressonância magnética (RM)em 19 pacientes com enxaqueca, antes (1ᵃ RM) e após (2ᵃ RM) o tratamento profilático, e comparada com controles, usando o programa FreeSurfer. Mudanças corticais foram correlacionadas com o índice de cefaleia (HI). Resultados O hemisfério direito apresentou aumento da espessura no córtex do cúneus e pré-cúneus, parietal superior e somatossensitivo na primeira RM e na segunda RM, em comparação aos controles. Após correção para comparações múltiplas, nenhuma região cortical se mostrou estatisticamente diferente entre a primeira e a segunda RM. A regressão mostrou correlação (negativa) significativa entre melhora do HI e mudanças na espessura cortical do cíngulo posterior esquerdo. Conclusão Existem alterações de espessura cortical em pacientes com enxaqueca em relação a controles em áreas envolvidas com processamento visual e com a dor. As alterações corticais no cíngulo posterior esquerdo variaram de acordo com a frequência e intensidade das crises.


Subject(s)
Humans , Male , Female , Adult , Young Adult , Gyrus Cinguli/pathology , Migraine Disorders/pathology , Migraine Disorders/prevention & control , Organ Size , Reference Values , Severity of Illness Index , Magnetic Resonance Imaging/methods , Case-Control Studies , Monte Carlo Method , Reproducibility of Results , Retrospective Studies , Treatment Outcome , Statistics, Nonparametric , Post-Exposure Prophylaxis/methods , Gyrus Cinguli/diagnostic imaging , Migraine Disorders/diagnostic imaging
15.
Braz. j. med. biol. res ; 51(1): e6698, 2018. tab, graf
Article in English | LILACS | ID: biblio-889006

ABSTRACT

Given that the pathogenesis of ankylosing spondylitis (AS) remains unclear, the aim of this study was to detect the potentially functional pathway cross-talk in AS to further reveal the pathogenesis of this disease. Using microarray profile of AS and biological pathways as study objects, Monte Carlo cross-validation method was used to identify the significant pathway cross-talks. In the process of Monte Carlo cross-validation, all steps were iterated 50 times. For each run, detection of differentially expressed genes (DEGs) between two groups was conducted. The extraction of the potential disrupted pathways enriched by DEGs was then implemented. Subsequently, we established a discriminating score (DS) for each pathway pair according to the distribution of gene expression levels. After that, we utilized random forest (RF) classification model to screen out the top 10 paired pathways with the highest area under the curve (AUCs), which was computed using 10-fold cross-validation approach. After 50 bootstrap, the best pairs of pathways were identified. According to their AUC values, the pair of pathways, antigen presentation pathway and fMLP signaling in neutrophils, achieved the best AUC value of 1.000, which indicated that this pathway cross-talk could distinguish AS patients from normal subjects. Moreover, the paired pathways of SAPK/JNK signaling and mitochondrial dysfunction were involved in 5 bootstraps. Two paired pathways (antigen presentation pathway and fMLP signaling in neutrophil, as well as SAPK/JNK signaling and mitochondrial dysfunction) can accurately distinguish AS and control samples. These paired pathways may be helpful to identify patients with AS for early intervention.


Subject(s)
Humans , Spondylitis, Ankylosing/genetics , Signal Transduction/genetics , Gene Expression , Receptor Cross-Talk/physiology , Gene Expression Profiling/methods , Reference Values , Monte Carlo Method , Area Under Curve , Databases, Genetic , Microarray Analysis/methods , Genetic Association Studies
16.
Biosci. j. (Online) ; 33(3): 652-659, may/jun. 2017. tab, graf
Article in English | LILACS | ID: biblio-966223

ABSTRACT

The objective of this study was to evaluate the use of stochastic simulations in decision-making regarding the economic viability of feedlot finishing Charolais steers slaughtered at different weights (420, 460 or 500 kg live weight). Monte Carlo simulation was used, with or without Spearman correlation, to evaluate the risk associated with random input variables, and to compare the curves of pairs of slaughter weights by stochastic dominance. The financial indicator net present value (NPV) was the output variable. The expected means and standard deviations for the slaughter weights of 420, 460 and 500 kg were USD 28.77 ± 53.90; USD 36.27 ± 57.22 and USD 54.60 ± 66.74 for simulation with correlation, and USD 28.75 ± 96.15; USD 36.17 ± 103.11 and USD 54.53 ± 111.96 for simulation without correlation. The simulations without correlation were found to overestimate the standard deviation by 75% compared to simulations performed in addition to correlation analysis. The correlation between random input variables should be prioritized, as this resulted in better estimates of risk associated with investment. For all simulated situations, the lowest slaughter weights dominated the largest, according to the first- and second-order stochastic dominance criteria. For the simulation with correlation, the probability of NPV 0 was 29.4, 24.4 and 19.4% for slaughter weights of 420, 460 and 500 kg, respectively. Interpretation of these simulations allowed classification of feedlot technology as high risk, with a high probability of economic loss.


O objetivo deste estudo foi avaliar o uso de simulação estocástica na tomada de decisão sobre a viabilidade econômica da terminação em confinamento de novilhos Charolês abatidos com diferentes pesos (420, 460 ou 500 kg de peso vivo). O método de Monte Carlo foi utilizado para avaliar-se o risco com o uso ou não de correlação de Spearman entre as variáveis aleatórias de entrada, e comparar as curvas de pesos de abate pela dominância estocástica. O indicador financeiro Valor Presente Líquido - VPL foi a variável de saída. As médias esperadas e respectivos desvios padrão para os pesos de abate de 420, 460 e 500 kg foram de USD 28,77 ± 53,90; USD 36,27 ± 57,22 e USD 54,60 ± 66,74 para simulação com correlação e USD 28,75 ± 96,15; USD 36,17 ± 103,11 e USD 54,53 ± 111,96 para simulação sem correlação. As simulações sem o uso de correlação superestimaram o desvio padrão na ordem de 75%, em relação as simulações com uso de correlação. O uso da correlação entre variáveis aleatórias de entrada deve ser priorizado, pois resulta em melhores estimativas do risco associado ao investimento. Em todas as situações simuladas, os menores pesos de abate dominaram os maiores, de acordo com o critério de primeira e segunda ordem de dominância estocástica. Na simulação com correlação, a probabilidade de NPV0 foram 29,4; 24,4 e 19,4%, respectivamente, para pesos de abate de 420, 460 e 500 kg. A interpretação das simulações permitiu classificar a tecnologia de confinamento como de alto risco, com alta probabilidade de perda econômica.


Subject(s)
Monte Carlo Method , Statistics , Decision Making , Animal Culling
17.
Biosci. j. (Online) ; 33(3): 660-669, may/jun. 2017. graf, tab
Article in English | LILACS | ID: biblio-966224

ABSTRACT

The economic viability of feedlot Aberdeen Angus steers fed with diets composed of different concentrate levels (CL) in dry matter (25, 40, 55 or 70%) was estimated using Monte Carlo simulation combined with Spearman rank correlation, considering nine random input variables, as well as stochastic dominance (DOM) and sensitivity (SENS) analyses. For the financial indicator simulation, net present value (NPV), cash flow with indicators of performance, and the probability distribution of all cost and income items (from 2003 to 2014) were used. Latin hypercube sampling and a Mersenne Twister random number generator was employed for the simulation, which included 2000 interactions. The expected mean values ± standard deviation for NPV (USD/animal) were 44.94 ± 68.01, 44.50 ± 69.25, 15.39 ± 69.22 and 54.20 ± 71.58 for the diets containing 25, 40, 55 and 70% CL, respectively. The probability of NPV 0 was 76.8, 76.0, 57.9 and 78.1%, respectively, from the smallest to largest CL. The DOM analysis showed that 25 and 40% CL have similar probability curves, the 70% level dominated the remaining and all CL dominated 55%. According to SENS analysis, the items that most influenced the NPV were, in decreasing order, finished and feeder cattle price, initial and final weights, concentrate and roughage price, concentrate intake, minimum rate of attractiveness and roughage intake. Based on the simulation results, the 70% CL showed a higher NPV and greater likelihood of economic viability. The probabilistic simulation technique is an interesting tool for decision-making in investment projects with beef cattle feedlot, therefore, further studies in this line of research is recommended.


Estimou-se o risco da viabilidade econômica do confinamento de novilhos Aberdeen Angus alimentados com dietas com diferentes níveis de concentrado (NC) na matéria seca (25, 40, 55 ou 70%), utilizando simulação de Monte Carlo associado com o uso de correlação de Spearman entre nove variáveis aleatórias de entrada, dominância estocástica (DOM) e análise de sensibilidade (SENS). Para a simulação do indicador financeiro Valor Presente Líquido (VPL), foi utilizado fluxo de caixa com indicadores de desempenho e distribuição de probabilidade de todos os itens de custos e receitas (anos de 2003 a 2014). Amostragem de Hipercubo Latino e gerador de números aleatórios Mersenne Twister foram utilizados para a simulação com 2.000 interações. Os valores médios esperados para VPL ± desvio padrão (USD/animal) foram de: 44,94 ± 68,01; 44,50 ± 69,25; 15,39 ± 69,22 e 54,20 ± 71,58, respectivamente, para 25, 40, 55 e 70% NC. As probabilidades do VPL 0 foram 76,8%; 76,0%; 57,9% e 78,1%, respectivamente, do menor para maior NC. A análise de DOM demonstrou que 25 e 40% de concentrado apresentam curvas de probabilidade similares; 70% dominou os demais e 55% foi dominado por todos os NC. De acordo com a SENS, os itens que mais influenciaram no VPL foram, em ordem decrescente, os preços do boi gordo e magro, os pesos final e inicial, preços do concentrado e do volumoso, consumo de concentrado, taxa mínima de atratividade e consumo de volumoso. Com base nos resultados de simulação, o NC de 70% apresentou maior VPL e maior probabilidade de viabilidade econômica. A técnica de simulação probabilística demonstrou ser interessante ferramenta para tomada de decisões em projetos de investimento com confinamento de bovinos de corte, sugerindo a expansão de estudos nesta linha de pesquisa.


Subject(s)
Monte Carlo Method , Risk Assessment , Animal Feed , Animal Husbandry
18.
Biosci. j. (Online) ; 33(1): 125-134, jan./feb. 2017. ilus, tab
Article in English | LILACS | ID: biblio-965879

ABSTRACT

The economic viability of feedlot zebu bulls, slaughtered at 450 kg after 90 days of feeding with diets consisting of different proportions of concentrate in dry matter (40, 60 or 80%), was estimated using Monte Carlo simulations, with or without the inclusion of Spearman rank correlations among random input variables, stochastic dominance (DOM) and sensitivity analysis (SENS). The roughage used was chopped sugar cane. Cash flow with indicators of performance, and probability distributions of all items of cost and revenue (from 2003 to 2014), were used to stimulate net present value (NPV), the financial indicator. Latin hypercube sampling and a Mersenne Twister random number generator were employed for the simulation with 2000 interactions. The risk was found to be more accurately estimated when correlations between random input variables were included (probability of NPV 0 ± standard deviation was 35 ± 166.05% and 31 ± 139.75% for the simulation without and with correlation, respectively). Considering this result, DOM and SENS were only carried out including these correlations. The expected value for NPV was similar between the different levels of concentrate (average USD -62/animal and NPV 0 of 33%) according to DOM analysis of simulations including correlations. From the SENS analysis, the final weight, finished cattle price, feeder cattle price and initial weight were the items with the greatest influence on NPV, regardless of the level of concentrate used, followed by intake and the cost-related items of diet and minimum rate of attractiveness. Based on the results obtained by simulation, the direct benefit of feedlot could be classified as high risk, suggesting the increased use of Monte Carlo simulation for decision-making.


Estimou-se o risco da viabilidade econômica do confinamento de bovinos zebuínos abatidos com 450 kg após 90 dias de alimentação, com dietas com diferentes proporções de concentrado na matéria seca (40, 60 ou 80%), utilizando simulação de Monte Carlo associado ou não com o uso de correlação de Spearman entre as variáveis aleatórias de entrada, dominância estocástica (DOM) e análise de sensibilidade (SENS). O volumoso utilizado foi cana-deaçúcar picada. Para a simulação do indicador financeiro Valor Presente Líquido (VPL), foi utilizado fluxo de caixa com indicadores de desempenho e distribuição de probabilidade de todos os itens de custos e receitas (anos de 2003 a 2014). Amostragem de Hipercubo Latino e gerador de números aleatórios Mersenne Twister foram utilizados para a simulação com 2.000 interações. O risco foi estimado com maior precisão incluindo correlações entre variáveis aleatórias de entrada (probabilidades de VPL 0 ± desvio padrão foram 35 ± 166,05% and 31 ± 139,75% para a simulação com e sem correlação, respectivamente). A partir deste resultado, DOM e SENS foram realizadas apenas com correlação entre variáveis aleatórias de entrada. O valor esperado para VPL foi semelhante entre os diferentes níveis de concentrado (média de USD -62 / animal e VPL 0 de 33%), de acordo com a análise de DOM das simulações com correlação. Na SENS, independentemente do nível de concentrado usado, o peso final, os preços do boi gordo e magro e peso inicial foram os itens mais importantes a influenciar o VPL, seguido de consumo da dieta, preços da dieta e taxa mínima de atratividade. Com base nos resultados de simulação, poderia ser classificado o benefício direto de confinamento como de alto risco, sugerindo a expansão dos estudos com uso da técnica de simulação de Monte Carlo na tomada de decisões.


Subject(s)
Cattle , Monte Carlo Method , Livestock , Animal Husbandry
19.
Ciênc. saúde coletiva ; 22(1): 221-233, jan. 2017. tab, graf
Article in Portuguese | LILACS | ID: biblio-839908

ABSTRACT

Resumo A fim de esclarecer qual programa de assistência farmacêutica, Rede Farmácia de Minas Gerais RFMG ou Farmácia Popular do Brasil FPB, se apresenta como o mais eficiente sob a perspectiva do financiador público foi realizada uma avaliação econômica. O modelo desenvolvido consiste em um levantamento dos custos incorridos até a dispensação de medicamentos. A análise de Monte Carlo foi utilizada para estimar valores a partir das incertezas. Considerando que a população inicialmente estimada no RFMG fosse atendida em sua totalidade no PFPB, haveria um custo incremental de R$ 139.324.050,19. A análise de Monte Carlo mostrou-se favorável ao RFMG. Foram realizadas 10 mil simulações resultando no valor médio de R$ 114.053.709,99 para RFMG e de R$ 254.106.120,65 para o FPB. O Brasil apresenta uma formulação avançada de políticas públicas na saúde. A Política Nacional de Medicamentos enfatiza a necessidade de fortalecimento da assistência farmacêutica para além da mera aquisição. O modelo público, coerente com princípios e diretrizes do SUS, apresenta-se com condições mais adequadas para garantir assistência integral e universal de qualidade. A avaliação econômica reforça essa afirmativa, pois encontrou maior eficiência na alternativa de aplicação dos recursos diretamente na rede pública.


Abstract We conducted an economic assessment of the Pharmaceutical Assistance - Rede Farmácia de Minas Gerais-RFMG and Farmácia Popular do Brasil-FPB to ascertain which of the two models stands out as the most efficient. To do this, a model, which consisted of a study of incurred costs in both programs, up to the dispensing of medicine to citizens, was developed. The uncertainties of the proposed model were tested using the Monte Carlo method. If the entire population initially estimated in the RFMG were attended in the FPB, there would be an additional cost of R$ 139,324,050.19. The sensitivity analysis appeared to be favorable to the RFMG. A total of 10000 simulations were carried out, resulting in a median value of R$ 114,053,709.99 for the RFMG and R$ 254,106,120.65 for the FPB. The current National Drug Policy emphasizes the need to strengthen pharmaceutical services beyond the mere acquisition and delivery of pharmaceutical products. The public healthcare service model, consistent with the principles and guidelines of the SUS, seems to be more appropriate in ensuring complete and universal quality healthcare services to the citizens. The economic study conducted reinforces this fact, as it appears to be a more efficient alternative of the direct use of resources in the public health network.


Subject(s)
Humans , Models, Economic , Pharmaceutical Preparations/economics , Pharmaceutical Services/economics , Public Health/economics , Brazil , Delivery of Health Care/economics , Delivery of Health Care/organization & administration , Monte Carlo Method , National Health Programs/economics , Pharmaceutical Services/organization & administration
20.
Braz. J. Pharm. Sci. (Online) ; 53(3): e00163, 2017. tab, graf
Article in English | LILACS | ID: biblio-889391

ABSTRACT

ABSTRACT Analytical results are widely used to assess batch-by-batch conformity, pharmaceutical equivalence, as well as in the development of drug products. Despite this, few papers describing the measurement uncertainty estimation associated with these results were found in the literature. Here, we described a simple procedure used for estimating measurement uncertainty associated with the dissolution test of acetaminophen tablets. A fractionate factorial design was used to define a mathematical model that explains the amount of acetaminophen dissolved (%) as a function of time of dissolution (from 20 to 40 minutes), volume of dissolution media (from 800 to 1000 mL), pH of dissolution media (from 2.0 to 6.8), and rotation speed (from 40 to 60 rpm). Using Monte Carlo simulations, we estimated measurement uncertainty for dissolution test of acetaminophen tablets (95.2 ± 1.0%), with a 95% confidence level. Rotation speed was the most important source of uncertainty, contributing about 96.2% of overall uncertainty. Finally, it is important to note that the uncertainty calculated in this paper reflects the expected uncertainty to the dissolution test, and does not consider variations in the content of acetaminophen.


Subject(s)
Tablets/analysis , Monte Carlo Method , Acetaminophen/analysis , Techniques, Measures, Measurement Equipment , Dissolution/methods
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