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1.
Braz. j. biol ; 84: e248656, 2024. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1345542

RESUMO

Abstract Several species of Cichla successfully colonized lakes and reservoirs of Brazil, since the 1960's, causing serious damage to local wildlife. In this study, 135 peacock bass were collected in a reservoir complex in order to identify if they represented a single dominant species or multiple ones, as several Cichla species have been reported in the basin. Specimens were identified by color pattern, morphometric and meristic data, and using mitochondrial markers COI, 16S rDNA and Control Region (CR). Overlapping morphological data and similar coloration patterns prevented their identification using the taxonomic keys to species identification available in the literature. However, Bayesian and maximum likelihood from sequencing data demonstrated the occurrence of a single species, Cichla kelberi. A single haplotype was observed for the 16S and CR, while three were detected for COI, with a dominant haplotype present in 98.5% of the samples. The extreme low diversity of the transplanted C. kelberi evidenced a limited number of founding maternal lineages. The success of this colonization seems to rely mainly on abiotic factors, such as increased water transparency of lentic environments that favor visual predators that along with the absence of predators, have made C. kelberi a successful invader of these reservoirs.


Resumo Muitas espécies de Cichla colonizaram com sucesso lagos e reservatórios do Brasil desde os anos 1960, causando graves prejuízos à vida selvagem nesses locais. Neste estudo, 135 tucunarés foram coletados em um complexo de reservatórios a fim de identificar se representavam uma espécie dominante ou múltiplas espécies, uma vez que diversas espécies de Cichla foram registradas na bacia. Os espécimes foram identificados com base na coloração, dados morfométricos e merísticos, e por marcadores mitocondriais COI, 16S rDNA e Região Controle (RC). A sobreposição dos dados morfométricos e o padrão similar de coloração impediram a identificação utilizando as chaves de identificação disponíveis na literatura. Entretanto, as análises bayesiana e de máxima verossimilhança de dados moleculares demonstraram a ocorrência de uma única espécie, Cichla kelberi. Um único haplótipo foi observado para o 16S e RC, enquanto três foram detectados para o COI, com um haplótipo dominante presente em 98,5% das amostras. A baixa diversidade nos exemplares introduzidos de C. kelberi evidenciou um número limitado de linhagens maternas fundadoras. O sucesso da invasão parece depender de fatores abióticos, como a maior transparência da água de ambientes lênticos que favorece predadores visuais que, atrelado à ausência de predadores, fez do C. kelberi um invasor bem-sucedido nesses reservatórios.


Assuntos
Animais , Ciclídeos/genética , Filogenia , Variação Genética/genética , Haplótipos/genética , Lagos , Teorema de Bayes
2.
Braz. j. biol ; 83: e252656, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1345534

RESUMO

Abstract The genus Artemisia L. of the family Asteraceae is systematically very complex. The aim of this study was to evaluate taxonomic positions of taxa of the subgenus Artemisia belonging to the genus Artemisia in Turkey using some molecular techniques. In this molecular study, 44 individuals belong to 14 species of the subgenus Artemisia were examined. Analyses were performed on the combined dataset using maximum parsimony, maximum likelihood and Bayesian inference and Molecular parameters obtained from co-evaluations of sequences of the psbA-trnH, ITS and ETS regions of examined individuals were used in the phylogenetic tree drawing. According to the results of this study, two molecular groups have been formed based on the DNA sequence similarity of the species, but there are no obvious morphological characters corresponding to two molecular groups. There is no also agreement between the two molecular groups and the two morphological groups formed according to the hairiness condition of the receptacle of species. Due to the lack of molecular significance of their receptacles with or without hair, dividing of the subgenus Artemisia species into new subgenera or sections was not considered appropriate. Likewise, it has been found that with or without hair on the corolla lobes of the central hermaphrodite disc flowers have no molecular significance. It was found that there were no gene flow and hybridization between the 14 species of the subgenus Artemisia and these 14 species were found completed their speciation. This study is important as it is the first molecular based study relating with belong to subgenus Artemisia species growing naturally in Turkey. In addition, new haplotypes related to the populations of Turkey belonging to the subgenus Artemisia taxa were reported by us for the first time and added to the GenBank database.


Resumo O gênero Artemisia L. da família Asteraceae é sistematicamente muito complexo. O objetivo deste estudo foi avaliar as posições taxonômicas de táxons do subgênero Artemisia pertencentes ao gênero Artemisia na Turquia usando algumas técnicas moleculares. Neste estudo molecular, 44 indivíduos pertencentes a 14 espécies do subgênero Artemisia foram examinados. As análises foram realizadas no conjunto de dados combinado usando máxima parcimônia, máxima verossimilhança e inferência bayesiana e parâmetros moleculares obtidos a partir de coavaliações de sequências das regiões psbA-trnH, ITS e ETS de indivíduos examinados foram usados ​​no desenho da árvore filogenética. De acordo com os resultados deste estudo, dois grupos moleculares foram formados com base na similaridade da sequência de DNA das espécies, mas não há caracteres morfológicos óbvios correspondentes a dois grupos moleculares. Também não há concordância entre os dois grupos moleculares e os dois grupos morfológicos formados de acordo com a condição de pilosidade do receptáculo da espécie. Devido à falta de significado molecular de seus receptáculos com ou sem cabelo, a divisão das espécies do subgênero Artemisia em novos subgêneros ou seções não foi considerada apropriada. Da mesma forma, verificou-se que com ou sem cabelo nos lobos da corola das flores do disco hermafrodita central não tem significado molecular. Constatou-se que não houve fluxo gênico e hibridização entre as 14 espécies do subgênero Artemisia e essas 14 espécies concluíram sua especiação. Este estudo é importante porque é o primeiro estudo de base molecular relacionado com espécies pertencentes ao subgênero Artemisia crescendo naturalmente na Turquia. Além disso, novos haplótipos relacionados às populações da Turquia pertencentes ao subgênero Artemisia taxa foram relatados por nós pela primeira vez e adicionados ao banco de dados do GenBank.


Assuntos
Humanos , Artemisia/genética , Filogenia , Turquia , Teorema de Bayes , Hibridização Genética
3.
Braz. j. biol ; 83: e249756, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1345533

RESUMO

Abstract Ri chicken is the most popular backyard chicken breed in Vietnam, but little is known about the growth curve of this breed. This study compared the performances of models with three parameters (Gompertz, Brody, and Logistic) and models containing four parameters (Richards, Bridges, and Janoschek) for describing the growth of Ri chicken. The bodyweight of Ri chicken was recorded weekly from week 1 to week 19. Growth models were fitted using minpack.lm package in R software and Akaike's information criterion (AIC), Bayesian information criterion (BIC), and root mean square error (RMSE) were used for model comparison. Based on these criteria, the models having four parameters showed better performance than the ones with three parameters, and the Richards model was the best one for males and females. The lowest and highest value of asymmetric weights (α) were obtained by Bridges and Brody models for each of sexes, respectively. Age and weight estimated by the Richard model were 8.46 and 7.51 weeks and 696.88 and 487.58 g for males and for females, respectively. Differences in the growth curves were observed between males and female chicken. Overall, the results suggested using the Richards model for describing the growth curve of Ri chickens. Further studies on the genetics and genomics of the obtained growth parameters are required before using them for the genetic improvement of Ri chickens.


Resumo O frango Ri é a raça de frango de quintal mais popular do Vietnã, mas pouco se sabe sobre a curva de crescimento dessa raça. Este estudo comparou o desempenho de modelos com três parâmetros (Gompertz, Brody e Logistic) e modelos contendo quatro parâmetros (Richards, Bridges e Janoschek) para descrever o crescimento do frango Ri. O peso corporal do frango Ri foi registrado semanalmente da semana 1 à semana 19. Os modelos de crescimento foram ajustados usando o pacote minpack.lm no software R e o critério de informação de Akaike (AIC); critério de informação bayesiano (BIC) e erro quadrático médio (RMSE) foram usados ​​para comparação de modelos. Com base nesses critérios, os modelos com quatro parâmetros apresentaram melhor desempenho do que os com três parâmetros, sendo o modelo de Richards o melhor para homens e mulheres. O menor e o maior valor dos pesos assimétricos (α) foram obtidos pelos modelos Bridges e Brody para cada um dos sexos, respectivamente. A idade e o peso estimados pelo modelo de Richard foram de 8,46 e 7,51 semanas e 696,88 e 487,58 g para homens e mulheres, respectivamente. Diferenças nas curvas de crescimento foram observadas entre frangos machos e fêmeas. No geral, os resultados sugeriram o uso do modelo de Richards para descrever a curva de crescimento de frangos Ri. Mais estudos sobre a genética e genômica dos parâmetros de crescimento obtidos são necessários antes de usá-los para o melhoramento genético de frangos Ri.


Assuntos
Humanos , Animais , Masculino , Feminino , Galinhas , Modelos Teóricos , Peso Corporal , Teorema de Bayes , Grupo com Ancestrais do Continente Asiático , Modelos Biológicos
4.
JMIR Public Health Surveill ; 8(6): e37491, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35700022

RESUMO

BACKGROUND: The vastly increasing number of reported HIV and AIDS cases in Luzhou, China, in recent years, coupled with the city's unique geographical location at the intersection of 4 provinces, makes it particularly important to conduct a spatiotemporal analysis of HIV and AIDS cases. OBJECTIVE: The aim of this study is to understand the spatiotemporal distribution of HIV and the factors influencing this distribution in Luzhou, China, from 2011 to 2020. METHODS: Data on the incidence of HIV and AIDS in Luzhou from 2011 to 2020 were obtained from the AIDS Information Management System of the Luzhou Center for Disease Control and Prevention. ArcGIS was used to visualize the spatiotemporal distribution of HIV and AIDS cases. The Bayesian spatiotemporal model was used to investigate factors affecting the spatiotemporal distribution of HIV and AIDS, including the gross domestic product (GDP) per capita, urbanization rate, number of hospital beds, population density, and road mileage. RESULTS: The reported incidence of HIV and AIDS rose from 8.50 cases per 100,000 population in 2011 to 49.25 cases per 100,000 population in 2020-an increase of 578.87%. In the first 5 years, hotspots were concentrated in Jiangyang district, Longmatan district, and Luxian county. After 2016, Luzhou's high HIV incidence areas gradually shifted eastward, with Hejiang county having the highest average prevalence rate (41.68 cases per 100,000 population) from 2011 to 2020, being 2.28 times higher than that in Gulin county (18.30 cases per 100,000), where cold spots were concentrated. The risk for the incidence of HIV and AIDS was associated with the urbanization rate, population density, and GDP per capita. For every 1% increase in the urbanization rate, the relative risk (RR) increases by 1.3%, while an increase of 100 people per square kilometer would increase the RR by 8.7%; for every 1000 Yuan (US $148.12) increase in GDP per capita, the RR decreases by 1.5%. CONCLUSIONS: In Luzhou, current HIV and AIDS prevention and control efforts must be focused on the location of each district or county government; we suggest the region balance urban development and HIV and AIDS prevention. Moreover, more attention should be paid to economically disadvantaged areas.


Assuntos
Síndrome de Imunodeficiência Adquirida , Síndrome de Imunodeficiência Adquirida/epidemiologia , Teorema de Bayes , China/epidemiologia , Humanos , Incidência , Análise Espaço-Temporal
5.
Sci Rep ; 12(1): 9840, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701514

RESUMO

Electrocardiographic (ECG) Heart Age conveying cardiovascular risk has been estimated by both Bayesian and artificial intelligence approaches. We hypothesised that explainable measures from the 10-s 12-lead ECG could successfully predict Bayesian 5-min ECG Heart Age. Advanced analysis was performed on ECGs from healthy subjects and patients with cardiovascular risk or proven heart disease. Regression models were used to predict patients' Bayesian 5-min ECG Heart Ages from their standard, resting 10-s 12-lead ECGs. The difference between 5-min and 10-s ECG Heart Ages were analyzed, as were the differences between 10-s ECG Heart Age and the chronological age (the Heart Age Gap). In total, 2,771 subjects were included (n = 1682 healthy volunteers, n = 305 with cardiovascular risk factors, n = 784 with cardiovascular disease). Overall, 10-s Heart Age showed strong agreement with the 5-min Heart Age (R2 = 0.94, p < 0.001, mean ± SD bias 0.0 ± 5.1 years). The Heart Age Gap was 0.0 ± 5.7 years in healthy individuals, 7.4 ± 7.3 years in subjects with cardiovascular risk factors (p < 0.001), and 14.3 ± 9.2 years in patients with cardiovascular disease (p < 0.001). Heart Age can be accurately estimated from a 10-s 12-lead ECG in a transparent and explainable fashion based on known ECG measures, without deep neural network-type artificial intelligence techniques. The Heart Age Gap increases markedly with cardiovascular risk and disease.


Assuntos
Inteligência Artificial , Doenças Cardiovasculares , Teorema de Bayes , Doenças Cardiovasculares/diagnóstico , Pré-Escolar , Eletrocardiografia/métodos , Humanos , Lactente , Recém-Nascido , Redes Neurais de Computação
6.
Stat Med ; 41(14): 2665-2687, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35699116

RESUMO

The article develops marginal models for multivariate longitudinal responses. Overall, the model consists of five regression submodels, one for the mean and four for the covariance matrix, with the latter resulting by considering various matrix decompositions. The decompositions that we employ are intuitive, easy to understand, and they do not rely on any assumptions such as the presence of an ordering among the multivariate responses. The regression submodels are semi-parametric, with unknown functions represented by basis function expansions. We use spike-slap priors for the regression coefficients to achieve variable selection and function regularization, and to obtain parameter estimates that account for model uncertainty. An efficient Markov chain Monte Carlo algorithm for posterior sampling is developed. The simulation study presented investigates the gains that one may have when considering multivariate longitudinal analyses instead of univariate ones, and whether these gains can counteract the negative effects of missing data. We apply the methods on a highly unbalanced longitudinal dataset with four responses observed over a period of 20 years.


Assuntos
Teorema de Bayes , Simulação por Computador , Humanos , Cadeias de Markov , Método de Monte Carlo , Análise Multivariada
7.
Stat Med ; 41(14): 2602-2626, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35699121

RESUMO

The mixture cure model for analyzing survival data is characterized by the assumption that the population under study is divided into a group of subjects who will experience the event of interest over some finite time horizon and another group of cured subjects who will never experience the event irrespective of the duration of follow-up. When using the Bayesian paradigm for inference in survival models with a cure fraction, it is common practice to rely on Markov chain Monte Carlo (MCMC) methods to sample from posterior distributions. Although computationally feasible, the iterative nature of MCMC often implies long sampling times to explore the target space with chains that may suffer from slow convergence and poor mixing. Furthermore, extra efforts have to be invested in diagnostic checks to monitor the reliability of the generated posterior samples. A sampling-free strategy for fast and flexible Bayesian inference in the mixture cure model is suggested in this article by combining Laplace approximations and penalized B-splines. A logistic regression model is assumed for the cure proportion and a Cox proportional hazards model with a P-spline approximated baseline hazard is used to specify the conditional survival function of susceptible subjects. Laplace approximations to the posterior conditional latent vector are based on analytical formulas for the gradient and Hessian of the log-likelihood, resulting in a substantial speed-up in approximating posterior distributions. The spline specification yields smooth estimates of survival curves and functions of latent variables together with their associated credible interval are estimated in seconds. A fully stochastic algorithm based on a Metropolis-Langevin-within-Gibbs sampler is also suggested as an alternative to the proposed Laplacian-P-splines mixture cure (LPSMC) methodology. The statistical performance and computational efficiency of LPSMC is assessed in a simulation study. Results show that LPSMC is an appealing alternative to MCMC for approximate Bayesian inference in standard mixture cure models. Finally, the novel LPSMC approach is illustrated on three applications involving real survival data.


Assuntos
Algoritmos , Teorema de Bayes , Humanos , Cadeias de Markov , Método de Monte Carlo , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes
8.
PLoS One ; 17(6): e0269369, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35709188

RESUMO

Recently there have been tremendous efforts to develop statistical procedures which allow to determine subgroups of patients for which certain treatments are effective. This article focuses on the selection of prognostic and predictive genetic biomarkers based on a relatively large number of candidate Single Nucleotide Polymorphisms (SNPs). We consider models which include prognostic markers as main effects and predictive markers as interaction effects with treatment. We compare different high-dimensional selection approaches including adaptive lasso, a Bayesian adaptive version of the Sorted L-One Penalized Estimator (SLOBE) and a modified version of the Bayesian Information Criterion (mBIC2). These are compared with classical multiple testing procedures for individual markers. Having identified predictive markers we consider several different approaches how to specify subgroups susceptible to treatment. Our main conclusion is that selection based on mBIC2 and SLOBE has similar predictive performance as the adaptive lasso while including substantially fewer biomarkers.


Assuntos
Genômica , Polimorfismo de Nucleotídeo Único , Teorema de Bayes , Biomarcadores , Marcadores Genéticos , Humanos , Prognóstico
9.
BMC Bioinformatics ; 23(1): 235, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35710340

RESUMO

BACKGROUND: Pan-omics, pan-cancer analysis has advanced our understanding of the molecular heterogeneity of cancer. However, such analyses have been limited in their ability to use information from multiple sources of data (e.g., omics platforms) and multiple sample sets (e.g., cancer types) to predict clinical outcomes. We address the issue of prediction across multiple high-dimensional sources of data and sample sets by using molecular patterns identified by BIDIFAC+, a method for integrative dimension reduction of bidimensionally-linked matrices, in a Bayesian hierarchical model. Our model performs variable selection through spike-and-slab priors that borrow information across clustered data. We use this model to predict overall patient survival from the Cancer Genome Atlas with data from 29 cancer types and 4 omics sources and use simulations to characterize the performance of the hierarchical spike-and-slab prior. RESULTS: We found that molecular patterns shared across all or most cancers were largely not predictive of survival. However, our model selected patterns unique to subsets of cancers that differentiate clinical tumor subtypes with markedly different survival outcomes. Some of these subtypes were previously established, such as subtypes of uterine corpus endometrial carcinoma, while others may be novel, such as subtypes within a set of kidney carcinomas. Through simulations, we found that the hierarchical spike-and-slab prior performs best in terms of variable selection accuracy and predictive power when borrowing information is advantageous, but also offers competitive performance when it is not. CONCLUSIONS: We address the issue of prediction across multiple sources of data by using results from BIDIFAC+ in a Bayesian hierarchical model for overall patient survival. By incorporating spike-and-slab priors that borrow information across cancers, we identified molecular patterns that distinguish clinical tumor subtypes within a single cancer and within a group of cancers. We also corroborate the flexibility and performance of using spike-and-slab priors as a Bayesian variable selection approach.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Teorema de Bayes , Humanos , Projetos de Pesquisa
10.
Sci Rep ; 12(1): 10137, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710930

RESUMO

Response inhibition is typically considered a brain mechanism selectively triggered by particular "inhibitory" stimuli or events. Based on recent research, an alternative non-selective mechanism was proposed by several authors. Presumably, the inhibitory brain activity may be triggered not only by the presentation of "inhibitory" stimuli but also by any imperative stimuli, including Go stimuli, when the context is uncertain. Earlier support for this notion was mainly based on the absence of a significant difference between neural activity evoked by equiprobable Go and NoGo stimuli. Equiprobable Go/NoGo design with a simple response time task limits potential confounds between response inhibition and accompanying cognitive processes while not preventing prepotent automaticity. However, previous neuroimaging studies used classical null hypothesis significance testing, making it impossible to accept the null hypothesis. Therefore, the current research aimed to provide evidence for the practical equivalence of neuronal activity in the Go and NoGo trials using Bayesian analysis of functional magnetic resonance imaging (fMRI) data. Thirty-four healthy participants performed a cued Go/NoGo task with an equiprobable presentation of Go and NoGo stimuli. To independently localize brain areas associated with response inhibition in similar experimental conditions, we performed a meta-analysis of fMRI studies using equal-probability Go/NoGo tasks. As a result, we observed overlap between response inhibition areas and areas that demonstrate the practical equivalence of neuronal activity located in the right dorsolateral prefrontal cortex, parietal cortex, premotor cortex, and left inferior frontal gyrus. Thus, obtained results favour the existence of non-selective response inhibition, which can act in settings of contextual uncertainty induced by the equal probability of Go and NoGo stimuli.


Assuntos
Inibição Psicológica , Imageamento por Ressonância Magnética , Teorema de Bayes , Mapeamento Encefálico , Eletroencefalografia , Potenciais Evocados/fisiologia , Humanos , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Incerteza
11.
Biom J ; 64(5): 934-947, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35692061

RESUMO

In a basket trial, a new treatment is tested in different subgroups, called the baskets. In oncology, the baskets usually comprise patients with different primary tumor sites but a common biomarker. Most basket trials are uncontrolled phase II trials and investigate a binary endpoint such as tumor response. To combine the data of baskets that show a similar response to the treatment, many basket trial designs use Bayesian borrowing methods. This increases the power compared to a basketwise analysis. However, it can lead to posterior probabilities that are not monotonically increasing in the number of responses. We show that, as a consequence, two types of counterintuitive decisions can arise-one that occurs within a single trial and one that occurs when the results are compared between different trials. We propose two monotonicity conditions for the inference in basket trials. Using a design recently proposed by Fujikawa and colleagues, we investigate the case of a single-stage basket trial with equal sample sizes in all baskets and show that, as the number of baskets increases, these conditions are violated for a wide range of different borrowing strengths. We show that in the investigated scenarios pruning baskets can help to ensure that the monotonicity conditions hold and investigate how this affects type I error rate and power.


Assuntos
Neoplasias , Teorema de Bayes , Humanos , Probabilidade , Projetos de Pesquisa , Tamanho da Amostra
12.
Front Public Health ; 10: 861587, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692346

RESUMO

Context: Foundational Capabilities (FC) are the public health (PH) infrastructure areas that are essential for local health departments (LHDs) to support a "minimum package" of programs and services that promote population health. Despite being a critical component of LHD programs, FC are chronically underfunded, and studies specific to the relationship between LHD FC expenditures and their performance-the LHDs' ability to provide essential PH programs and services to their community-have not been previously reported. Public Health Accreditation Board (PHAB) accreditation is a nationally recognized accreditation program for PH agencies. PHAB accreditation assesses LHDs' performance against sets of standards that are based on the 10 essential PH services. Alignment between FC and the PHAB standards presents a means for assessing LHD FC expenditures relative to their performance in PHAB accreditation standards. Objectives: We examined the association between LHD total FC expenditures, as well as FC funding allocation patterns, and performance score on selected PHAB accreditation standards. Methods: We used Bayesian regression methods to estimate the coefficients for the aggregate performance score, and performance scores on individual PHAB standards. Results: Analyses showed that a dollar increase in total FC expenditures is associated with a 0.2% increase in the aggregate performance score in selected PHAB standards as well as the performance score on most of the standards examined. LHDs that allocated FC budgets more evenly across FC programs were found to be more likely to have higher scores. Conclusions: Investment in FC could improve LHD performance scores in PHAB accreditation standards and support LHDs' capability for improving community health outcomes. Allocating available FC resources across the various FC programs could support better LHD performance, as indicated by accreditation scores. This study contributes to advancing the understanding of public health finances in relation to performance and could help guide effective LHD resource allocation.


Assuntos
Governo Local , Saúde Pública , Acreditação/métodos , Teorema de Bayes , Gastos em Saúde , Melhoria de Qualidade
13.
Front Endocrinol (Lausanne) ; 13: 881983, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692402

RESUMO

Background: Predicting the number of oocytes retrieved (NOR) following controlled ovarian stimulation (COS) is the only way to ensure effective and safe treatment in assisted reproductive technology (ART). To date, there have been limited studies about predicting specific NOR, which hinders the development of individualized treatment in ART. Objective: To establish an online tool for predicting NOR. Materials and Methods: In total, 621 prospective routine gonadotropin releasing hormone (GnRH) antagonist COS cycles were studied. Independent variables included age, body mass index, antral follicle counts, basal FSH, basal and increment of anti-mullerian hormone, Luteinizing hormon, estradiol, testosterone, androstenedione, and inhibin B. The outcome variable was NOR. The independent variables underwent appropriate transformation to achieve a better fit for a linear relationship with NOR. Pruned forward selection with holdback validation was then used to establish predictive models. Corrected Akaike's information criterion, Schwarz-Bayesian information criterion, scaled -log[likelihood], and the generalized coefficient of determination (R 2) were used for model evaluation. Results: A multiple negative binomial regression model was used for predicting NOR because it fitted a negative binomial distribution. We established Model 1, using basal ovarian reserve markers, and Model 2, using both basal and early dynamic markers for predicting NOR following COS. The generalized R 2 values were 0.54 and 0.51 for Model 1 and 0.64 and 0.62 for Model 2 in the training and validation sets, respectively. Conclusion: Models 1 and 2 could be applied to different scenarios. For directing the starting dose of recombinant follicle stimulation hormone (rFSH), Model 1 using basic predictors could be used prior to COS. Model 2 could be used for directing the adjustment of rFSH dosages during COS. An online tool (http://121.43.113.123:8002/) based on these two models is also developed. We anticipate that the clinical application of this tool could help the ART clinics to reduce iatrogenic ovarian under- or over-responses, and could reduce costs during COS for ART.


Assuntos
Reserva Ovariana , Comportamento de Utilização de Ferramentas , Teorema de Bayes , Fertilização In Vitro , Hormônio Foliculoestimulante , Hormônio Liberador de Gonadotropina , Antagonistas de Hormônios/uso terapêutico , Humanos , Oócitos , Indução da Ovulação , Estudos Prospectivos
14.
Front Endocrinol (Lausanne) ; 13: 895458, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692410

RESUMO

Aims: This study aimed to assess the impact of different antidiabetic agents on individuals with diabetes and COVID-19. Methods: We searched PubMed, Web of Science, Embase, and Cochrane Library databases from inception to October 31, 2021 and included seven antidiabetic agents. The data were pooled via traditional pairwise meta-analysis and Bayesian network meta-analysis. Results: The pairwise meta-analysis included 35 studies. Metformin (odds ratio (OR), 0.74; P=0.001), dipeptidyl peptidase-4 inhibitors (DPP4i) (OR, 0.88; P=0.04), sodium-glucose cotransporter-2 inhibitors (SGLT2i) (OR, 0.82; P=0.001), and glucagon-like peptide-1 receptor agonists (GLP1RA) (OR, 0.91; P=0.02) treatment were associated with lower COVID-19 mortality in individuals with diabetes compared to respective non-users. However, insulin treatment resulted in higher mortality (OR, 1.8; P=0.001). Mortality did not significantly differ in sulfonylurea (OR, 0.97; P=0.56) and thiazolidinediones (TZDs) (OR, 1.00; P=0.96) users. Furthermore, due to limited data, we analyzed five antidiabetic agents (metformin, DPP4i, sulfonylurea, insulin, and SGLT2i) and found no association between them and severe disease risk (all P>0.05). The Bayesian network meta-analysis included 18 studies. GLP1RA and SGLT2i had the highest first and second rank probability (67.3% and 62.5%, respectively). Insulin showed the maximum probability of ranking seventh (97.0%). Metformin had the third and fourth highest rank probability of 44.8% and 38.9%, respectively. Meanwhile, DPP4i had the fifth-highest rank probability of 42.4%, followed by sulfonylurea at 45.1%. Conclusion: Metformin, DPP4i, SGLT2i, and GLP1RA treatments were highly possible to reduced COVID-19 mortality risk in individuals with diabetes, while insulin might be related to increased mortality risk. Sulfonylurea and TZDs treatments were not associated with mortality. None of the antidiabetic agents studied were associated with the risk of severe disease. Additionally, GLP1RA probably had the most significant protective effect against death, followed by SGLT2i and metformin. Systematic Review Registration: PROSPERO (CRD42021288200).


Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Metformina , Inibidores do Transportador 2 de Sódio-Glicose , Tiazolidinedionas , Teorema de Bayes , COVID-19/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Metformina/uso terapêutico , Metanálise em Rede , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Tiazolidinedionas/uso terapêutico , Resultado do Tratamento
15.
J Healthc Eng ; 2022: 2051642, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693888

RESUMO

Survival analysis is a collection of statistical techniques which examine the time it takes for an event to occur, and it is one of the most important fields in biomedical sciences and other variety of scientific disciplines. Furthermore, the computational rapid advancements in recent decades have advocated the application of Bayesian techniques in this field, giving a powerful and flexible alternative to the classical inference. The aim of this study is to consider the Bayesian inference for the generalized log-logistic proportional hazard model with applications to right-censored healthcare data sets. We assume an independent gamma prior for the baseline hazard parameters and a normal prior is placed on the regression coefficients. We then obtain the exact form of the joint posterior distribution of the regression coefficients and distributional parameters. The Bayesian estimates of the parameters of the proposed model are obtained using the Markov chain Monte Carlo (McMC) simulation technique. All computations are performed in Bayesian analysis using Gibbs sampling (BUGS) syntax that can be run with Just Another Gibbs Sampling (JAGS) from the R software. A detailed simulation study was used to assess the performance of the proposed parametric proportional hazard model. Two real-survival data problems in the healthcare are analyzed for illustration of the proposed model and for model comparison. Furthermore, the convergence diagnostic tests are presented and analyzed. Finally, our research found that the proposed parametric proportional hazard model performs well and could be beneficial in analyzing various types of survival data.


Assuntos
Atenção à Saúde , Teorema de Bayes , Simulação por Computador , Humanos , Cadeias de Markov , Método de Monte Carlo
16.
Comput Intell Neurosci ; 2022: 9773452, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694598

RESUMO

In China, the application of corpus in language teaching, especially in English and American literature teaching, is still in the preliminary research stage, and there are various shortcomings, which have not been paid due attention by front-line educators. Constructing English and American literature corpus according to certain principles can effectively promote English and American literature teaching. The research of this paper is devoted to how to automatically build a corpus of English and American literature. In the process of keyword extraction, key phrases and keywords are effectively combined. The similarity between atomic events is calculated by the TextRank algorithm, and then the first N sentences with high similarity are selected and sorted. Based on ML (machine learning) text classification method, a combined classifier based on SVM (support vector machine) and NB (Naive Bayes) is proposed. The experimental results show that, from the point of view of accuracy and recall, the classification effect of the combined algorithm proposed in this paper is the best among the three methods. The best classification results of accuracy, recall, and F value are 0.87, 0.9, and 0.89, respectively. Experimental results show that this method can quickly, accurately, and persistently obtain high-quality bilingual mixed web pages.


Assuntos
Idioma , Aprendizado de Máquina , Algoritmos , Teorema de Bayes , Máquina de Vetores de Suporte
17.
Accid Anal Prev ; 173: 106717, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35643025

RESUMO

This paper presents an empirical analysis of factors contributing to roadway infrastructure damage from expressway accidents, using a Bayesian random parameters Tobit model. The accident data collected from Kaiyang Expressway, China in 2014 and 2015 are used for the empirical analysis. The results of parameter estimation in the proposed model indicate that: the effects of vehicle types are significantly heterogeneous across observations, and that the effects of horizontal curvature, time of day, vehicle registered province, and accident type are also significant but homogeneous across observations. The marginal effects of these contributing factors are calculated to explicitly quantify their impacts on road infrastructure damage. According to the analysis results, some strategies pertaining to safety education, traffic enforcement, roadway design, and intelligence transportation technology are advocated to reduce road infrastructure damage from expressway accidents.


Assuntos
Acidentes de Trânsito , Acidentes de Trânsito/prevenção & controle , Teorema de Bayes , China , Humanos , Segurança
19.
PLoS Negl Trop Dis ; 16(6): e0010436, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35653307

RESUMO

Widespread application of insecticide remains the primary form of control for Chagas disease in Central America, despite only temporarily reducing domestic levels of the endemic vector Triatoma dimidiata and having little long-term impact. Recently, an approach emphasizing community feedback and housing improvements has been shown to yield lasting results. However, the additional resources and personnel required by such an intervention likely hinders its widespread adoption. One solution to this problem would be to target only a subset of houses in a community while still eliminating enough infestations to interrupt disease transfer. Here we develop a sequential sampling framework that adapts to information specific to a community as more houses are visited, thereby allowing us to efficiently find homes with domiciliary vectors while minimizing sampling bias. The method fits Bayesian geostatistical models to make spatially informed predictions, while gradually transitioning from prioritizing houses based on prediction uncertainty to targeting houses with a high risk of infestation. A key feature of the method is the use of a single exploration parameter, α, to control the rate of transition between these two design targets. In a simulation study using empirical data from five villages in southeastern Guatemala, we test our method using a range of values for α, and find it can consistently select fewer homes than random sampling, while still bringing the village infestation rate below a given threshold. We further find that when additional socioeconomic information is available, much larger savings are possible, but that meeting the target infestation rate is less consistent, particularly among the less exploratory strategies. Our results suggest new options for implementing long-term T. dimidiata control.


Assuntos
Doença de Chagas , Inseticidas , Triatoma , Animais , Teorema de Bayes , Doença de Chagas/epidemiologia , Doença de Chagas/prevenção & controle , Vetores de Doenças
20.
PLoS Comput Biol ; 18(6): e1010161, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35679241

RESUMO

Given the crucial role of climate in malaria transmission, many mechanistic models of malaria represent vector biology and the parasite lifecycle as functions of climate variables in order to accurately capture malaria transmission dynamics. Lower dimension mechanistic models that utilize implicit vector dynamics have relied on indirect climate modulation of transmission processes, which compromises investigation of the ecological role played by climate in malaria transmission. In this study, we develop an implicit process-based malaria model with direct climate-mediated modulation of transmission pressure borne through the Entomological Inoculation Rate (EIR). The EIR, a measure of the number of infectious bites per person per unit time, includes the effects of vector dynamics, resulting from mosquito development, survivorship, feeding activity and parasite development, all of which are moderated by climate. We combine this EIR-model framework, which is driven by rainfall and temperature, with Bayesian inference methods, and evaluate the model's ability to simulate local transmission across 42 regions in Rwanda over four years. Our findings indicate that the biologically-motivated, EIR-model framework is capable of accurately simulating seasonal malaria dynamics and capturing of some of the inter-annual variation in malaria incidence. However, the model unsurprisingly failed to reproduce large declines in malaria transmission during 2018 and 2019 due to elevated anti-malaria measures, which were not accounted for in the model structure. The climate-driven transmission model also captured regional variation in malaria incidence across Rwanda's diverse climate, while identifying key entomological and epidemiological parameters important to seasonal malaria dynamics. In general, this new model construct advances the capabilities of implicitly-forced lower dimension dynamical malaria models by leveraging climate drivers of malaria ecology and transmission.


Assuntos
Culicidae , Malária , Animais , Teorema de Bayes , Clima , Humanos , Malária/epidemiologia , Mosquitos Vetores
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