Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 479
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Genet Epidemiol ; 47(6): 409-431, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37101379

RESUMO

In genetic studies, many phenotypes have multiple naturally ordered discrete values. The phenotypes can be correlated with each other. If multiple correlated ordinal traits are analyzed simultaneously, the power of analysis may increase significantly while the false positives can be controlled well. In this study, we propose bivariate functional ordinal linear regression (BFOLR) models using latent regressions with cumulative logit link or probit link to perform a gene-based analysis for bivariate ordinal traits and sequencing data. In the proposed BFOLR models, genetic variant data are viewed as stochastic functions of physical positions, and the genetic effects are treated as a function of physical positions. The BFOLR models take the correlation of the two ordinal traits into account via latent variables. The BFOLR models are built upon functional data analysis which can be revised to analyze the bivariate ordinal traits and high-dimension genetic data. The methods are flexible and can analyze three types of genetic data: (1) rare variants only, (2) common variants only, and (3) a combination of rare and common variants. Extensive simulation studies show that the likelihood ratio tests of the BFOLR models control type I errors well and have good power performance. The BFOLR models are applied to analyze Age-Related Eye Disease Study data, in which two genes, CFH and ARMS2, are found to strongly associate with eye drusen size, drusen area, age-related macular degeneration (AMD) categories, and AMD severity scale.


Assuntos
Degeneração Macular , Modelos Genéticos , Humanos , Fenótipo , Degeneração Macular/genética , Simulação por Computador , Modelos Lineares
2.
Chembiochem ; 25(13): e202400243, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696752

RESUMO

Successful implementation of enzymes in practical application hinges on the development of efficient mass production techniques. However, in a heterologous expression system, the protein is often unable to fold correctly and, thus, forms inclusion bodies, resulting in the loss of its original activity. In this study, we present a new and more accurate model for predicting amino acids associated with an increased L-amino acid oxidase (LAO) solubility. Expressing LAO from Rhizoctonia solani in Escherichia coli and combining random mutagenesis and statistical logistic regression, we modified 108 amino acid residues by substituting hydrophobic amino acids with serine and hydrophilic amino acids with alanine. Our results indicated that specific mutations in Euclidean distance, glycine, methionine, and secondary structure increased LAO expression. Furthermore, repeated mutations were performed for LAO based on logistic regression models. The mutated LAO displayed a significantly increased solubility, with the 6-point and 58-point mutants showing a 2.64- and 4.22-fold increase, respectively, compared with WT-LAO. Ultimately, using recombinant LAO in the biotransformation of α-keto acids indicates its great potential as a biocatalyst in industrial production.


Assuntos
Escherichia coli , L-Aminoácido Oxidase , Solubilidade , Escherichia coli/genética , Escherichia coli/metabolismo , L-Aminoácido Oxidase/genética , L-Aminoácido Oxidase/metabolismo , L-Aminoácido Oxidase/química , Modelos Logísticos , Rhizoctonia/enzimologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/química
3.
Br J Psychiatry ; : 1-8, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38708564

RESUMO

BACKGROUND: Despite the recognised importance of mental disorders and social disconnectedness for mortality, few studies have examined their co-occurrence. AIMS: To examine the interaction between mental disorders and three distinct aspects of social disconnectedness on mortality, while taking into account sex, age and characteristics of the mental disorder. METHOD: This cohort study included participants from the Danish National Health Survey in 2013 and 2017 who were followed until 2021. Survey data on social disconnectedness (loneliness, social isolation and low social support) were linked with register data on hospital-diagnosed mental disorders and mortality. Poisson regression was applied to estimate independent and joint associations with mortality, interaction contrasts and attributable proportions. RESULTS: A total of 162 497 individuals were followed for 886 614 person-years, and 9047 individuals (5.6%) died during follow-up. Among men, interaction between mental disorders and loneliness, social isolation and low social support, respectively, accounted for 47% (95% CI: 21-74%), 24% (95% CI: -15 to 63%) and 61% (95% CI: 35-86%) of the excess mortality after adjustment for demographics, country of birth, somatic morbidity, educational level, income and wealth. In contrast, among women, no excess mortality could be attributed to interaction. No clear trends were identified according to age or characteristics of the mental disorder. CONCLUSIONS: Mortality among men, but not women, with a co-occurring mental disorder and social disconnectedness was substantially elevated compared with what was expected. Awareness of elevated mortality rates among socially disconnected men with mental disorders could be of importance to qualify and guide prevention efforts in psychiatric services.

4.
Stat Med ; 43(3): 578-605, 2024 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-38213277

RESUMO

Research on dynamic treatment regimes has enticed extensive interest. Many methods have been proposed in the literature, which, however, are vulnerable to the presence of misclassification in covariates. In particular, although Q-learning has received considerable attention, its applicability to data with misclassified covariates is unclear. In this article, we investigate how ignoring misclassification in binary covariates can impact the determination of optimal decision rules in randomized treatment settings, and demonstrate its deleterious effects on Q-learning through empirical studies. We present two correction methods to address misclassification effects on Q-learning. Numerical studies reveal that misclassification in covariates induces non-negligible estimation bias and that the correction methods successfully ameliorate bias in parameter estimation.


Assuntos
Regras de Decisão Clínica , Aprendizado de Máquina , Humanos
5.
J Surg Res ; 294: 26-36, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37857140

RESUMO

INTRODUCTION: The prognosis and optimal treatment approach for stage I mixed germ cell cancers of the testis are not well-established. This study aimed to assess contemporary treatment rates and their correlation with the cancer-specific mortality (CSM) and other-cause mortality (OCM) in patients with stage I testicular mixed germ cell tumors (TMGCT) who underwent orchiectomy, comparing surveillance with active treatment, including chemotherapy (CHT) and retroperitoneal lymph node dissection (RPLND). METHODS: Retrospective analysis of clinical data from stage I TMGCT patients who underwent orchiectomy was conducted using the Surveillance, Epidemiology, and End Results database from 2004 to 2019. The annual percentage change (APC) in the use of surveillance, postoperative CHT, and RPLND was examined. Propensity score matching (PSM) and cumulative incidence, analyses were employed to compare differences in CSM and OCM between surveillance and active treatment, as well as between CHT and RPLND. Multivariate competing-risks regression models were utilized to investigate independent factors affecting CSM and OCM among stage I TMGCT patients. RESULTS: The study included 5743 individuals with stage I TMGCT that underwent surveillance (61.6%), CHT(27.2%), or RPLND (11.2%). Among them, 82 deaths were attributed to TMGCT, and 82 deaths resulted from other causes. Surveillance rates increased over time (APC: 0.635%, P = 0.008), as did CHT rates (APC: 0.863%, P < 0.001), while RPLND rates declined (APC: -0.96%, P < 0.001). After PSM, multivariate competing-risks regression analysis showed that, active treatment, compared to surveillance, was not an independent factor for CSM and OCM. In contrast, when compared to CHT, RPLND was an independent factor associated with lower CSM (hazard ratio = 0.247, 95% confidence interval: 0.08-0.761; P = 0.015), but not OCM (hazard ratio = 0.946, 95% confidence interval: 0.377-2.37; P = 0.91). CONCLUSIONS: Surveillance and CHT rates have increased over time for patients with stage I TMGCT following initial orchiectomy, while RPLND utilization has decreased. There was no significant difference in CSM between surveillance and active treatment groups, but RPLND demonstrated significantly lower CSM than CHT in active treatment. Our findings suggest that the usage of RPLND in patients with stage I TMGCT should be reconsidered.


Assuntos
Neoplasias Embrionárias de Células Germinativas , Neoplasias Testiculares , Masculino , Humanos , Orquiectomia/métodos , Prognóstico , Estudos Retrospectivos , Pontuação de Propensão , Neoplasias Embrionárias de Células Germinativas/cirurgia , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Testiculares/cirurgia , Excisão de Linfonodo/métodos , Espaço Retroperitoneal/cirurgia , Estadiamento de Neoplasias
6.
AIDS Behav ; 28(1): 285-299, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38087154

RESUMO

Improvement in treatment options has increased the survival of people living with HIV (PLHIV). Thus, we evaluated the factors associated with better health-related quality of life (HRQoL) among PLHIV in Brazil. This was a cross-sectional study carried out among 349 PLHIV. Data were collected using an interview-based questionnaire, and HRQoL was assessed by the Brazilian version of the WHOQOL HIV BREF instrument. We used non-hierarchical cluster analysis (K-means) to compile the WHOQOL HIV BREF's overall and domain scores into a unique more multidimensional measure for HRQoL consisting of three clusters: poor, fair and good; associations with clusters of better HRQoL were assessed using multinomial logistic regression models. The mean and median overall HRQoL scores were 15.13 (SD = 3.39) and 16, respectively. The reliability and validity of the Brazilian version of the WHOQOL HIV BREF instrument was confirmed among PLHIV in a non-metropolitan, medium-sized municipality of Brazil, which reaffirmed the cross-cultural validity of this instrument. The factors male sex; heterosexual and asexual orientations; higher individual income; undetectable viral load; absence of any comorbidity and presence of an infectious or a chronic comorbidity, with mental illness as the reference; and never having consumed illegal substances were independently associated with good HRQoL. Thus, the compilation of the WHOQOL HIV BREF's overall and domain scores into a unique multidimensional measure for HRQoL, which this study proposed for the first time, may facilitate more robust interpretations and models of predictors. These differentials could simplify HRQoL as an indicator of health and wellbeing to be routinely used as a key outcome in the clinical management of patients and in the global monitoring of health system responses to HIV.


RESUMEN: La mejora en las opciones de tratamiento ha aumentado la supervivencia de las personas que viven con el VIH (PVVIH). Por lo tanto, evaluamos los factores asociados con una mejor calidad de vida relacionada con la salud (CVRS) entre las PVVIH en Brasil. Se trata de un estudio transversal realizado con 349 PVVIH. Los datos se recopilaron mediante un cuestionario basado en entrevistas y la CVRS se evaluó mediante la versión brasileña del instrumento WHOQOL VIH BREF. Usamos un análisis de conglomerados no jerárquico (K-medias) para compilar las puntuaciones generales y de dominios del WHOQOL HIV BREF en una medida única más multidimensional para la CVRS que consta de tres conglomerados: deficiente, regular y bueno; y las asociaciones con grupos de mejor CVRS se evaluaron mediante modelos de regresión logística multinomial. Las puntuaciones de la CVRS global media y mediana fueron 15,13 (DE = 3,39) y 16. La confiabilidad y validez del WHOQOL VIH BREF versión brasileña fue confirmada entre personas que viven con el VIH en un municipio no metropolitano de mediana población de Brasil, lo que reafirma la validez transcultural de este instrumento. Los factores sexo masculino; orientaciones heterosexuales y asexuales; mayores ingresos individuales; carga viral indetectable; ausencia de comorbilidad y presencia de comorbilidad infecciosa o crónica, teniendo como referencia la enfermedad mental; y nunca haber consumido sustancias ilegales se asociaron de forma independiente con una buena CVRS. Por lo tanto, la compilación de las puntuaciones generales y de dominio del WHOQOL HIV BREF en una medida multidimensional única para la CVRS, que este estudio propuso por primera vez, puede facilitar interpretaciones y modelos de predictores más robustos. Estos diferenciales podrían simplificar la HRQoL como un indicador de salud y bienestar para ser utilizado de forma rutinaria como un resultado clave en el manejo clínico de los pacientes y en el monitoreo global de las respuestas del sistema de salud al VIH.


Assuntos
Infecções por HIV , Qualidade de Vida , Humanos , Masculino , Infecções por HIV/epidemiologia , Brasil/epidemiologia , Estudos Transversais , Reprodutibilidade dos Testes , Modelos Logísticos , Inquéritos e Questionários
7.
Environ Sci Technol ; 58(20): 8736-8747, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38723264

RESUMO

Inland waters (rivers, lakes, and reservoirs) and wetlands (marshes and coastal wetlands) represent large and continuous sources of nitrous oxide (N2O) emissions, in view of adequate biomass and anaerobic conditions. Considerable uncertainties remain in quantifying spatially explicit N2O emissions from aquatic systems, attributable to the limitations of models and a lack of comprehensive data sets. Herein, we conducted a synthesis of 1659 observations of N2O emission rates to determine the major environmental drivers across five aquatic systems. A framework for spatially explicit estimates of N2O emissions in China was established, employing a data-driven approach that upscaled from site-specific N2O fluxes to robust multiple-regression models. Results revealed the effectiveness of models incorporating soil organic carbon and water content for marshes and coastal wetlands, as well as water nitrate concentration and dissolved organic carbon for lakes, rivers, and reservoirs for predicting emissions. Total national N2O emissions from inland waters and wetlands were 1.02 × 105 t N2O yr-1, with contributions from marshes (36.33%), rivers (27.77%), lakes (25.27%), reservoirs (6.47%), and coastal wetlands (4.16%). Spatially, larger emissions occurred in the Songliao River Basin and Continental River Basin, primarily due to their substantial terrestrial biomass. This study offers a vital national inventory of N2O emissions from inland waters and wetlands in China, providing paradigms for the inventorying work in other countries and insights to formulate effective mitigation strategies for climate change.


Assuntos
Lagos , Óxido Nitroso , Áreas Alagadas , China , Óxido Nitroso/análise , Lagos/química , Monitoramento Ambiental , Rios/química
8.
Environ Res ; 257: 119400, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38866311

RESUMO

Most epidemiological studies on the associations between pesticides exposure and semen quality have been based on a single pesticide, with inconsistent major results. In contrast, there was limited human evidence on the potential effect of pesticides mixture on semen quality. Our study aimed to investigate the relationship of pesticide profiles with semen quality parameters among 299 non-occupationally exposed males aged 25-50 without any clinical abnormalities. Serum concentrations of 21 pesticides were quantified by gas chromatography-tandem mass spectrometry (GC-MS/MS). Semen quality parameters were abstracted from medical records. Generalized linear regression models (GLMs) and three mixture approaches, including weighted quantile sum regression (WQS), elastic net regression (ENR) and Bayesian kernel machine regression (BKMR), were applied to explore the single and mixed effects of pesticide exposure on semen quality. In GLMs, as the serum levels of Bendiocarb, ß-BHC, Clomazone, Dicrotophos, Dimethenamid, Paclobutrazole, Pentachloroaniline and Pyrimethanil increased, the straight-line velocity (VSL), linearity (LIN) and straightness (STR) decreased. This negative association also occurred between the concentration of ß-BHC, Pentachloroaniline, Pyrimethanil and progressive motility, total motility. In the WQS models, pesticides mixture was negatively associated with total motility and several sperm motility parameters (ß: -3.07∼-1.02 per decile, FDR-P<0.05). After screening the important pesticides derived from the mixture by ENR model, the BKMR models showed that the decreased qualities for VSL, LIN, and STR were also observed when pesticide mixtures were at ≥ 70th percentiles. Clomazone, Dimethenamid, and Pyrimethanil (Posterior inclusion probability, PIP: 0.2850-0.8900) were identified as relatively important contributors. The study provides evidence that exposure to single or mixed pesticide was associated with impaired semen quality.


Assuntos
Exposição Ambiental , Modelos Estatísticos , Praguicidas , Análise do Sêmen , Masculino , Humanos , Praguicidas/sangue , Praguicidas/toxicidade , Adulto , Exposição Ambiental/análise , Pessoa de Meia-Idade , Teorema de Bayes , Cromatografia Gasosa-Espectrometria de Massas
9.
Environ Res ; 251(Pt 2): 118629, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38490626

RESUMO

BACKGROUND: A knowledge gap exists regarding longitudinal assessment of personal radio-frequency electromagnetic field (RF-EMF) exposures globally. It is unclear how the change in telecommunication technology over the years translates to change in RF-EMF exposure. This study aims to evaluate longitudinal trends of micro-environmental personal RF-EMF exposures in Australia. METHODS: The study utilised baseline (2015-16) and follow-up (2022) data on personal RF-EMF exposure (88 MHz-6 GHz) measured across 18 micro-environments in Melbourne. Simultaneous quantile regression analysis was conducted to compare exposure data distribution percentiles, particularly median (P50), upper extreme value (P99) and overall exposure trends. RF-EMF exposures were compared across six exposure source types: mobile downlink, mobile uplink, broadcast, 5G-New Radio, Others and Total (of the aforementioned sources). Frequency-specific exposures measured at baseline and follow-up were compared. Total exposure across different groups of micro-environment types were also compared. RESULTS: For all micro-environmental data, total (median and P99) exposure levels did not significantly change at follow-up. Overall exposure trend of total exposure increased at follow-up. Mobile downlink contributed the highest exposure among all sources showing an increase in median exposure and overall exposure trend. Of seven micro-environment types, five of them showed total exposure levels (median and P99) and overall exposure trend increased at follow-up.


Assuntos
Campos Eletromagnéticos , Exposição Ambiental , Ondas de Rádio , Campos Eletromagnéticos/efeitos adversos , Ondas de Rádio/efeitos adversos , Humanos , Estudos Longitudinais , Vitória , Austrália
10.
Odontology ; 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38403674

RESUMO

To examine the differences between natural gingival colour in men and women. To determine the degree of predictability of changes in the gingival colour coordinates recorded for healthy gingiva, according to age, long-term medication, frequency of toothbrushing, and smoking habits. The CIELAB colour coordinates were recorded using a spectrophotometer for 360 Caucasian adult participants (aged 18-92 years), in three zones of the healthy attached gingiva of the maxillary central incisor. Regression models were created for each zone and each sex, taking the L*, a* and b* coordinates as dependent variables and age, frequency of toothbrushing, smoking habits (0-non-smoker; 1-smoker) and whether participants were taking long-term medication (0-no; 1-yes) as independent variables. The statistical analysis was conducted with SPSS version 26.0, using multiple regression models. Statistically significant differences between men and women were found only for colour coordinate b*, in all three zones. The only colour coordinate on which the predictor variables had a significant effect was the L* coordinate. In men, age and long-term medication had the greatest effect as predictors (maximum R2 = 0.149). In women, frequency of toothbrushing was the strongest predictor in the predictive models (maximum R2 = 0.099). The colour of gingiva in men contained a larger amount of blue, given that significantly lower values for colour coordinate b* were recorded in men than women, although this difference lacked clinical implications. For both sexes, the regression models produced had a modest predictive capacity. The L* coordinate was the dependent variable that showed the greatest predictability.

11.
Int J Environ Health Res ; : 1-15, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851885

RESUMO

A notable finding is that Kerala's capital Thiruvananthapuram has shown an increasing trend in lung cancer (LC) incidence. Long-term exposure to air pollution is a significant environmental risk factor for LC. This study investigated the spatial association between LC and exposure to air pollutants in Thiruvananthapuram, using Spatial Lag Model (SLM), Spatial Error Model (SEM), and Geographically Weighted Regression (GWR). The results showed that overall LC incidence rate was 111 per 105 males (age >60 years), whereas spatial distribution map revealed that 48% of the area had an incidence rate greater than 150. The results revealed a significant association between PM2.5 and LC. SLM was identified as the best model that predicted 62% variation in LC. GWR model improved model performance and made better local predictions in the southeastern parts of the study area. This study explores the effectiveness of spatial regression techniques for dealing spatial effects and pinpointing high-risk areas.

12.
Behav Res Methods ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39048860

RESUMO

When investigating unobservable, complex traits, data collection and aggregation processes can introduce distinctive features to the data such as boundedness, measurement error, clustering, outliers, and heteroscedasticity. Failure to collectively address these features can result in statistical challenges that prevent the investigation of hypotheses regarding these traits. This study aimed to demonstrate the efficacy of the Bayesian beta-proportion generalized linear latent and mixed model (beta-proportion GLLAMM) (Rabe-Hesketh et al., Psychometrika, 69(2), 167-90, 2004a, Journal of Econometrics, 128(2), 301-23, 2004c, 2004b; Skrondal and Rabe-Hesketh 2004) in handling data features when exploring research hypotheses concerning speech intelligibility. To achieve this objective, the study reexamined data from transcriptions of spontaneous speech samples initially collected by Boonen et al. (Journal of Child Language, 50(1), 78-103, 2023). The data were aggregated into entropy scores. The research compared the prediction accuracy of the beta-proportion GLLAMM with the normal linear mixed model (LMM) (Holmes et al., 2019) and investigated its capacity to estimate a latent intelligibility from entropy scores. The study also illustrated how hypotheses concerning the impact of speaker-related factors on intelligibility can be explored with the proposed model. The beta-proportion GLLAMM was not free of challenges; its implementation required formulating assumptions about the data-generating process and knowledge of probabilistic programming languages, both central to Bayesian methods. Nevertheless, results indicated the superiority of the model in predicting empirical phenomena over the normal LMM, and its ability to quantify a latent potential intelligibility. Additionally, the proposed model facilitated the exploration of hypotheses concerning speaker-related factors and intelligibility. Ultimately, this research has implications for researchers and data analysts interested in quantitatively measuring intricate, unobservable constructs while accurately predicting the empirical phenomena.

13.
Entropy (Basel) ; 26(6)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38920519

RESUMO

Ensuring that the proposed probabilistic model accurately represents the problem is a critical step in statistical modeling, as choosing a poorly fitting model can have significant repercussions on the decision-making process. The primary objective of statistical modeling often revolves around predicting new observations, highlighting the importance of assessing the model's accuracy. However, current methods for evaluating predictive ability typically involve model comparison, which may not guarantee a good model selection. This work presents an accuracy measure designed for evaluating a model's predictive capability. This measure, which is straightforward and easy to understand, includes a decision criterion for model rejection. The development of this proposal adopts a Bayesian perspective of inference, elucidating the underlying concepts and outlining the necessary procedures for application. To illustrate its utility, the proposed methodology was applied to real-world data, facilitating an assessment of its practicality in real-world scenarios.

14.
Entropy (Basel) ; 26(5)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38785671

RESUMO

Finite mixture of linear regression (FMLR) models are among the most exemplary statistical tools to deal with various heterogeneous data. In this paper, we introduce a new procedure to simultaneously determine the number of components and perform variable selection for the different regressions for FMLR models via an exponential power error distribution, which includes normal distributions and Laplace distributions as special cases. Under some regularity conditions, the consistency of order selection and the consistency of variable selection are established, and the asymptotic normality for the estimators of non-zero parameters is investigated. In addition, an efficient modified expectation-maximization (EM) algorithm and a majorization-maximization (MM) algorithm are proposed to implement the proposed optimization problem. Furthermore, we use the numerical simulations to demonstrate the finite sample performance of the proposed methodology. Finally, we apply the proposed approach to analyze a baseball salary data set. Results indicate that our proposed method obtains a smaller BIC value than the existing method.

15.
Clin Infect Dis ; 77(1): 120-126, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-36861203

RESUMO

BACKGROUND: Whether antimicrobial treatment improves long-term survival in patients with Mycobacterium avium complex pulmonary disease (MAC-PD) is unclear. METHODS: We analyzed survival in patients aged ≥18 years who were treated for MAC-PD at a tertiary referral center in South Korea between 1 January 2009 and 31 December 2020. Treatment exposure was divided into 4 time intervals: <6, ≥6 to <12, ≥12 to <18, and ≥18 months. Time-varying multivariable Cox proportional hazards models were used to calculate the all-cause mortality risk in each time interval. The model was adjusted for major clinical factors related to mortality including age, sex, body mass index, presence of cavities, erythrocyte sedimentation rate, positive acid-fast bacilli (AFB) smear, clarithromycin resistance, and comorbid conditions. RESULTS: A total of 486 patients treated for MAC-PD were included in the analysis. A significant inverse correlation was observed between mortality and duration of treatment (P for trend = .007). Long-term treatment (≥18 months) was significantly associated with reduced mortality (adjusted hazard ratio, 0.32 [95% confidence interval, .15-.71]). In subgroup analyses, patients with cavitary lesions (adjusted hazard ratio, 0.17 [95% confidence interval, .05-.57]) or positive AFB smears (0.13 [.02-.84]) at baseline maintained this significant inverse relationship between treatment duration and mortality. CONCLUSIONS: Long-term antimicrobial treatment should be actively considered in patients with progressive MAC-PD, especially in the presence of cavities or positive AFB smears indicative of high mycobacterial burden.


Assuntos
Pneumopatias , Infecção por Mycobacterium avium-intracellulare , Humanos , Adolescente , Adulto , Complexo Mycobacterium avium , Infecção por Mycobacterium avium-intracellulare/tratamento farmacológico , Infecção por Mycobacterium avium-intracellulare/microbiologia , Estudos Retrospectivos , Pneumopatias/microbiologia , Pulmão
16.
Breast Cancer Res ; 25(1): 12, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717842

RESUMO

BACKGROUND: Breast cancer neoadjuvant chemotherapy (NACT) allows for assessing tumor sensitivity to systemic treatment, planning adjuvant treatment and follow-up. However, a sufficiently large number of patients fail to achieve the desired level of pathological tumor response while optimal early response assessment methods have not been established now. In our study, we simultaneously assessed the early chemotherapy-induced changes in the tumor volume by ultrasound (US), the tumor oxygenation by diffuse optical spectroscopy imaging (DOSI), and the state of the tumor vascular bed by Doppler US to elaborate the predictive criteria of breast tumor response to treatment. METHODS: A total of 133 patients with a confirmed diagnosis of invasive breast cancer stage II to III admitted to NACT following definitive breast surgery were enrolled, of those 103 were included in the final analysis. Tumor oxygenation by DOSI, tumor volume by US, and tumor vascularization by Doppler US were determined before the first and second cycle of NACT. After NACT completion, patients underwent surgery followed by pathological examination and assessment of the pathological tumor response. On the basis of these, data regression predictive models were created. RESULTS: We observed changes in all three parameters 3 weeks after the start of the treatment. However, a high predictive potential for early assessment of tumor sensitivity to NACT demonstrated only the level of oxygenation, ΔStO2, (ρ = 0.802, p ≤ 0.01). The regression model predicts the tumor response with a high probability of a correct conclusion (89.3%). The "Tumor volume" model and the "Vascularization index" model did not accurately predict the absence of a pathological tumor response to treatment (60.9% and 58.7%, respectively), while predicting a positive response to treatment was relatively better (78.9% and 75.4%, respectively). CONCLUSIONS: Diffuse optical spectroscopy imaging appeared to be a robust tool for early predicting breast cancer response to chemotherapy. It may help identify patients who need additional molecular genetic study of the tumor in order to find the source of resistance to treatment, as well as to correct the treatment regimen.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Terapia Neoadjuvante/métodos , Mastectomia , Quimioterapia Adjuvante
17.
Stat Med ; 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36597179

RESUMO

We consider the conditional treatment effect for competing risks data in observational studies. We derive the efficient score for the treatment effect using modern semiparametric theory, as well as two doubly robust scores with respect to (1) the assumed propensity score for treatment and the censoring model, and (2) the outcome models for the competing risks. An important property regarding the estimators is rate double robustness, in addition to the classical model double robustness. Rate double robustness enables the use of machine learning and nonparametric methods in order to estimate the nuisance parameters, while preserving the root- n $$ n $$ asymptotic normality of the estimated treatment effect for inferential purposes. We study the performance of the estimators using simulation. The estimators are applied to the data from a cohort of Japanese men in Hawaii followed since 1960s in order to study the effect of mid-life drinking behavior on late life cognitive outcomes. The approaches developed in this article are implemented in the R package "HazardDiff".

18.
BMC Med Res Methodol ; 23(1): 51, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36829145

RESUMO

BACKGROUND: In health research, several chronic diseases are susceptible to competing risks (CRs). Initially, statistical models (SM) were developed to estimate the cumulative incidence of an event in the presence of CRs. As recently there is a growing interest in applying machine learning (ML) for clinical prediction, these techniques have also been extended to model CRs but literature is limited. Here, our aim is to investigate the potential role of ML versus SM for CRs within non-complex data (small/medium sample size, low dimensional setting). METHODS: A dataset with 3826 retrospectively collected patients with extremity soft-tissue sarcoma (eSTS) and nine predictors is used to evaluate model-predictive performance in terms of discrimination and calibration. Two SM (cause-specific Cox, Fine-Gray) and three ML techniques are compared for CRs in a simple clinical setting. ML models include an original partial logistic artificial neural network for CRs (PLANNCR original), a PLANNCR with novel specifications in terms of architecture (PLANNCR extended), and a random survival forest for CRs (RSFCR). The clinical endpoint is the time in years between surgery and disease progression (event of interest) or death (competing event). Time points of interest are 2, 5, and 10 years. RESULTS: Based on the original eSTS data, 100 bootstrapped training datasets are drawn. Performance of the final models is assessed on validation data (left out samples) by employing as measures the Brier score and the Area Under the Curve (AUC) with CRs. Miscalibration (absolute accuracy error) is also estimated. Results show that the ML models are able to reach a comparable performance versus the SM at 2, 5, and 10 years regarding both Brier score and AUC (95% confidence intervals overlapped). However, the SM are frequently better calibrated. CONCLUSIONS: Overall, ML techniques are less practical as they require substantial implementation time (data preprocessing, hyperparameter tuning, computational intensity), whereas regression methods can perform well without the additional workload of model training. As such, for non-complex real life survival data, these techniques should only be applied complementary to SM as exploratory tools of model's performance. More attention to model calibration is urgently needed.


Assuntos
Aprendizado de Máquina , Modelos Estatísticos , Humanos , Prognóstico , Estudos Retrospectivos , Redes Neurais de Computação
19.
BMC Infect Dis ; 23(1): 48, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36690944

RESUMO

BACKGROUND: Increased folic acid has been found to be latently protective against gynecological infection, including several kinds of vaginosis. In this study, we laid emphasis on whether RBC (Red Blood Cell) folate was associated with the infectious ratio of Trichomonas vaginalis, a kind of anaerobic parasitic protozoan. METHODS: We set RBC folate as the exposure variable and Trichomonas vaginalis as the outcome variable. Other subsidiary variables were regarded as covariates that may work as potential effect modifiers. The cross-sectional study was conducted with two merged waves of the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2004, and a sample of 1274 eligible women (1212 negative and 62 positive in Trichomonas vaginalis infection) was integrated for the exploration of the association between RBC folate and Trichomonas vaginalis infection. Multivariate regression analyses, subgroup analyses, and subsequent smooth curve fittings were conducted to estimate the relationship between RBC folate and Trichomonas vaginalis in women. RESULTS: In the multivariable logistic regression analyses, a negative association was observed between stratified RBC folate status and Trichomonas vaginalis infection with all confounders adjusted. Referencing the lowest RBC folate concentration quartile, the higher concentration quartiles reported a relatively lower infection ratio, while there was a weak correlation between total RBC folate concentration and T. vaginalis (Trichomonas vaginalis) infection. In subgroup analyses stratified by BMI and age, this association was only found significant in high age and BMI groups. CONCLUSIONS: The cross-sectional study indicated a negative association between RBC folic acid and Trichomonas vaginalis infection, and latent effects of BMI and age on the association were also found.


Assuntos
Tricomoníase , Vaginite por Trichomonas , Trichomonas vaginalis , Humanos , Feminino , Inquéritos Nutricionais , Estudos Transversais , Ácido Fólico , Eritrócitos , Vaginite por Trichomonas/diagnóstico
20.
Environ Sci Technol ; 57(48): 19532-19544, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37934506

RESUMO

In the United States (U.S.), studies on nitrogen dioxide (NO2) trends and pollution-attributable health effects have historically used measurements from in situ monitors, which have limited geographical coverage and leave 66% of urban areas unmonitored. Novel tools, including remotely sensed NO2 measurements and estimates of NO2 estimates from land-use regression and photochemical models, can aid in assessing NO2 exposure gradients, leveraging their complete spatial coverage. Using these data sets, we find that Black, Hispanic, Asian, and multiracial populations experience NO2 levels 15-50% higher than the national average in 2019, whereas the non-Hispanic White population is consistently exposed to levels that are 5-15% lower than the national average. By contrast, the in situ monitoring network indicates more moderate ethnoracial NO2 disparities and different rankings of the least- to most-exposed ethnoracial population subgroup. Validating these spatially complete data sets against in situ observations reveals similar performance, indicating that all these data sets can be used to understand spatial variations in NO2. Integrating in situ monitoring, satellite data, statistical models, and photochemical models can provide a semiobservational record, complete geospatial coverage, and increasingly high spatial resolution, enhancing future efforts to characterize, map, and track exposure and inequality for highly spatially heterogeneous pollutants like NO2.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Estados Unidos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Dióxido de Nitrogênio/análise , Monitoramento Ambiental , Exposição Ambiental , Material Particulado/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA