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1.
J Community Health ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300477

RESUMO

The COVID-19 pandemic was one of the deadliest global public health events. In the United States, over 1.1 million individuals have died, and now COVID-19 is the third leading cause of death (CDC, 2023). Vaccine uptake has stalled among different demographics. Vaccine hesitancy, a delay in accepting or refusing vaccines, poses a significant challenge regardless of the availability of safe and effective COVID-19 vaccines. This study aimed to identify disparate COVID-19 vaccine uptake among individuals in Western New York. The primary objective was to identify the factors contributing to lower rates of COVID-19 vaccination within this population.Data were collected from 585 adults recruited from 20 Niagara and Erie Counties sites using a self-administered survey on vaccine hesitancy, vaccination status, and COVID-19-related characteristics. The survey included the adult Vaccine Hesitancy Scale (aVHS) and acquired information on demographic characteristics and COVID-19 impact, knowledge, and information sources. Data were analyzed using descriptive statistics, a chi-squared test, a Wilcoxon rank-sum test, and a logistic regression model.Findings suggest that unvaccinated participants (n = 35) were concerned about vaccine side effects (48.6%). For vaccinated/unboosted participants (n = 52), they (40.0%) reported clinical concerns. After adjusting for gender and age, healthcare provider guidance and family guidance remained significant predictors of vaccination status, while clinical research studies were significant predictors of booster status. Findings from this study suggest public health interventions that target vaccine education and facilitate well-informed decisions about COVID-19 vaccines lead to less vaccine hesitancy.

2.
Pediatr Surg Int ; 40(1): 39, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38270628

RESUMO

BACKGROUND: We recently developed a preliminary predictive model identifying clinical and radiologic factors associated with the need for surgery following blunt abdominal trauma (BAT) in children. Our aim in this study was to further validate the factors in this predictive model in a multi-institutional study. METHODS: A retrospective chart review of pediatric patients from five pediatric trauma centers who experienced BAT between 2011 and 2020 was performed. Patients under 18 years of age who had BAT and computed tomography (CT) abdomen imaging were included. Children with evidence of pneumoperitoneum, and hemodynamic instability were excluded. Fisher's exact test was used for statistical analysis of the association between the following risk factors and need for laparotomy: abdominal wall bruising (AWB), abdominal pain/tenderness (APT), thoracolumbar fracture (TLF), presence of free fluid (FF), presence of solid organ injury (SOI). A predictive logistic regression model was then estimated employing these factors. FINDINGS: Seven hundred thirty-four patients were identified in this multi-institutional dataset with BAT and abdominal CT imaging, and 726 were included. Of those, 59 underwent surgical intervention (8.8%). Univariate analysis of association between the studied factors and need for surgical management showed that the presence of TLF (p < 0.01), APT (p < 0.01), FF (p < 0.01), and SOI (p < 0.01) were significantly associated. A predictive model was created using the 5 factors resulting in an area under the curve (AUC) of 0.80. For the motor vehicle collisions (MVC) group, only FF, SOI, and TLF are significantly associated with the need for surgical intervention. The AUC for the MVC group was 0.87. CONCLUSIONS: A clinical and radiologic prediction rule was validated using a large multi-institutional dataset of pediatric BAT patients, demonstrating a high degree of accuracy in identifying children who underwent surgery. FF, SOI, and TLF are the most important factors associated with the need for surgical intervention. LEVEL OF EVIDENCE: Level III.


Assuntos
Traumatismos Abdominais , Fraturas Ósseas , Ferimentos não Penetrantes , Humanos , Criança , Adolescente , Estudos Retrospectivos , Traumatismos Abdominais/diagnóstico por imagem , Traumatismos Abdominais/cirurgia , Tomografia Computadorizada por Raios X , Ferimentos não Penetrantes/diagnóstico por imagem , Ferimentos não Penetrantes/cirurgia , Dor Abdominal
3.
Am J Surg ; 228: 113-121, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37684168

RESUMO

BACKGROUND: Data on massive transfusion (MT) in geriatric trauma patients is lacking. This study aims to determine geriatric transfusion futility thresholds (TT) and TT variations based on frailty. METHODS: Patients from 2013 to 2018 TQIP database receiving MT were stratified by age and frailty. TTs and outcomes were compared between geriatric and younger adults and among geriatric adults based on frailty status. RESULTS: The TT was lower for geriatric than younger adults (34 vs 39 units; p â€‹= â€‹0.03). There was no difference in TT between the non-frail, frail, and severely frail geriatric adults (37, 30 and 25 units, respectively, p â€‹> â€‹0.05). Geriatric adults had higher mortality than younger adults (63.1% vs 45.8%, p < 0.01). Non-frail geriatric adults had the highest mortality (69.4% vs 56.5% vs 56.2%, p < 0.01). CONCLUSIONS: Geriatric patients have a lower TT than younger adults, irrespective of frailty. This may help improve outcomes and optimize MT utilization.


Assuntos
Fragilidade , Adulto , Idoso , Humanos , Idoso Fragilizado , Futilidade Médica , Avaliação Geriátrica , Tempo de Internação
4.
J Appl Stat ; 50(16): 3294-3311, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37969894

RESUMO

Brain imaging research is a very challenging topic due to complex structure and lack of explicitly identifiable features in the image. With the advancement of magnetic resonance imaging (MRI) technologies, such as diffusion tensor imaging (DTI), developing classification methods to improve clinical diagnosis is crucial. This paper proposes a classification method for DTI data based on a novel neural network strategy that combines a convolutional neural network (CNN) with a multilayer neural network using central-peripheral deviation (CPD), which reflects diffusion dynamics in the white matter by spatially evaluating the deviation of diffusion coefficients between the inner and outer parts of the brain. In our method, a multilayer perceptron (MLP) using CPD is combined with the final layers for classification after reducing the dimensions of images in the convolutional layers of the neural network architecture. In terms of training loss and the classification error, the proposed classification method improves the existing image classification with CNN. For real data analysis, we demonstrate how to process raw DTI image data sets obtained from a traumatic brain injury study (MagNeTS) and a brain atlas construction study (ICBM), and apply the proposed approach to the data, successfully improving classification performance with two age groups.

5.
Hosp Pediatr ; 13(9): 849-856, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37584151

RESUMO

BACKGROUND AND OBJECTIVES: Children and Youth with Special Health Care Needs (CYSHCN) have differing risk factors and injury characteristics compared with peers without special health care needs (SHCN). We examined the association between SHCN status and complications, mortality, and length of stay (LOS) after trauma hospitalization. METHODS: We conducted a cross-sectional study using 2018 data from the National Trauma Data Bank for patients aged 1 to 18 years (n = 108 062). We examined the following hospital outcomes: any complication reported, unplanned admission to the ICU, in-hospital mortality, and hospital and ICU LOS. Multivariate regression models estimated the effect of SHCN status on hospital outcomes after controlling for patient demographics, injury severity score, and Glasgow Coma Score. Subanalyses examined outcomes by age, SHCN, and injury severity score. RESULTS: CYSHCN encounters had a greater adjusted relative risk (ARR) of any hospital complications (ARR = 2.980) and unplanned admission to the ICU (ARR = 1.996) than encounters that did not report a SHCN (P < .001). CYSHCN had longer hospital (incidence rate ratio = 1.119) and ICU LOS (incidence rate ratio = 1.319, both P < .001). There were no statistically significant in-hospital mortality differences between CYSHCN and those without. Lower severity trauma was associated with a greater ARR of hospital complications for CYSHCN encounters versus non-CYSHCN encounters. CONCLUSIONS: CYSHCN, particularly those with lower-acuity injuries, are at greater risk for developing complications and requiring more care after trauma hospitalization. Future studies may examine mechanisms of hospital complications for traumatic injuries among CYSHCN to develop prevention and risk-minimization strategies.


Assuntos
Hospitalização , Unidades de Terapia Intensiva , Adolescente , Humanos , Criança , Estudos Transversais , Tempo de Internação , Fatores de Risco , Estudos Retrospectivos , Atenção à Saúde
6.
J Clin Neurosci ; 100: 169-174, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35487023

RESUMO

BACKGROUND/AIMS: There is a close link between iron and polyamine biosynthesis and metabolism. In a recent study, we reported alterations in the serum levels of hepcidin and other iron-related proteins in Alzheimer's disease (AD) patients (Sternberg et al., 2017). Based on these findings, this pilot study compared serum levels of one of the polyamines, Spermidine, between AD, mild cognitive impairment (MCI), and control subjects, correlating the levels with the existing clinical and neuroimaging data. METHODS: This cross-sectional study measured Spermidine levels in frozen serum samples of 43 AD patients, 12 MCI patients, and 21 age-matched controls, provided by the Oregon Alzheimer's Disease Center Bio-repository, using enzyme-linked immunosorbent assay. RESULTS: MCI patients showed significantly higher mean Spermidine serum levels compared to controls (P = 0.01), with a non-significant trend for higher Spermidine serum levels in pure AD (P = 0.08) participants compared to controls. Spermidine serum levels correlated with the values of cognitive assessment tests including MMSE (r = -0.705, P = 0.003), CDR (r = 0.751, P = 0.002), and CDR-SOB (r = 0.704, P = 0.007), in "pure" AD subgroup, suggesting that higher Spermidine serum levels in MCI can be a potential biomarker of conversion to dementia in subjects with AD underlying pathology. Furthermore, Spermidine serum levels correlated with serum levels of the chief iron regulatory protein, hepcidin in AD participants with a more advanced disease stage, indicated by MMSE (strata of 8-19, P = 0.02), and CDR-SOB (strata of 6-12, P = 0.03). CONCLUSION: Studies with larger cohort are warranted for defining the role of Spermidine in AD pathophysiology, and the utility of polyamines as biomarkers of progression of MCI to AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/diagnóstico por imagem , Biomarcadores , Disfunção Cognitiva/psicologia , Estudos Transversais , Progressão da Doença , Hepcidinas , Humanos , Ferro , Projetos Piloto , Espermidina
7.
J Trauma Acute Care Surg ; 93(3): 299-306, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35293370

RESUMO

BACKGROUND: Children and youth with special health care needs (CYSHCN) have or are at an increased risk for a chronic condition necessitating medical and related services beyond what children usually require. While evidence suggests that CYSHCN are at an increased risk of injury, little is known about this population within the trauma system. This study describes CYSHCN within the pediatric trauma system and examines patterns of injury risk (i.e., intent, place of injury, trauma type, and mechanism of injury) based on special health care need (SHCN) status. METHODS: For this cross-sectional study, we used data from the 2018 National Trauma Data Bank to identify pediatric encounters (1-18 years, N = 115,578) and compare demographics (sex, race/ethnicity, insurance status, and age) by CYSHCN status using χ 2 and t tests. Children and youth with special health care needs encounters were compared with non-SHCN encounters using multinomial logistic regression models, controlling for demographics. RESULTS: Overall, 16.7% pediatric encounters reported an SHCN. Children and youth with special health care needs encounters are older, and a higher proportion is publicly insured than non-SHCN encounters ( p < 0.001). Furthermore, CYSHCN encounters have a higher risk of assault (relative risk, 1.331) and self-inflicted (relative risk, 4.208) injuries relative to unintentional injury ( p < 0.001), as well as a higher relative risk of traumatic injury occurring in a private residence ( p < 0.01) than other locations such as school (relative risk, 0.894). Younger CYSHCN encounters have a higher risk of assault relative to unintentional injury when compared with non-SHCN encounters ( p < 0.01). Pediatric trauma encounters reporting mental health and alcohol/substance use disorder SHCN have a higher probability of self-inflicted and assault injuries than non-SHCN encounters ( p < 0.001). CONCLUSIONS: These findings suggest that CYSHCN have different traumatic injury patterns than their non-SHCN peers, particularly in terms of intentional and private residence injury, and deserve a special focus for traumatic injury prevention. LEVEL OF EVIDENCE: Prognostic/epidemiologic, level III.


Assuntos
Necessidades e Demandas de Serviços de Saúde , Adolescente , Criança , Doença Crônica , Estudos Transversais , Humanos
8.
Health Serv Res ; 57(1): 200-211, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34643942

RESUMO

OBJECTIVE: To examine a robust relative risk (RR) estimation for survey data analysis with ideal inferential properties under various model assumptions. DATA SOURCES: We employed secondary data from the Household Component of the 2000-2016 US Medical Expenditure Panel Survey (MEPS). STUDY DESIGN: We investigate a broad range of data-balancing techniques by implementing influence function (IF) methods, which allows us to easily estimate the variability for the RR estimates in the complex survey setting. We conduct a simulation study of seasonal influenza vaccine effectiveness to evaluate these approaches and discuss techniques that show robust inferential performance across model assumptions. DATA COLLECTION/EXTRACTION METHODS: Demographic information, vaccine status, and self-administered questionnaire surveys were obtained from the longitudinal data files. We linked this information with medical condition files and medical event to extract the disease type and associated expenditures for each medical visit. We excluded individuals who were 18 years or younger at the beginning of each panel. PRINCIPAL FINDINGS: Under various model assumptions, the IF methods show robust inferential performance when the data-balancing procedures are incorporated. Once IF methods and data-balancing techniques are implemented, contingency table-based RR estimation yields a comparable result to the generalized linear model approach. We demonstrate the applicability of the proposed methods for complex survey data using 2000-2016 MEPS data. When employing these methods, we find a significant, negative association between vaccine effectiveness (VE) estimates and influenza-incurred expenditures. CONCLUSIONS: We describe and demonstrate a robust method for RR estimation and relevant inferences for influenza vaccine effectiveness using MEPS data. The proposed method is flexible and can be extended to weighted data for survey data analysis. Hence, these methods have great potential for health services research, especially when data are nonexperimental and imbalanced.


Assuntos
Simulação por Computador , Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Adulto , Idoso , Estudos de Casos e Controles , Epidemias/prevenção & controle , Feminino , Humanos , Influenza Humana/epidemiologia , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa , Fatores de Risco
9.
J Chromatogr A ; 1639: 461894, 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33497832

RESUMO

Inverse gas chromatography was employed to investigate the sorption and diffusion of hydrocarbons into polydimethylsiloxane (PDMS) in the headspace-solid phase microextraction (HS-SPME) sampling process. Six hydrocarbons as molecular probes and two types of non-cross-linked PDMS with different average molecular weights as stationary phases were used in this study. Experimental measurements with columns containing a PDMS stationary phase were carried out to obtain specific retention volumes, molar enthalpies of sorption, interaction parameters, diffusion coefficients, and activation energies of diffusion of hydrocarbon probes over temperatures ranging from 60 to 90°C. The primary driving force of the hydrocarbon sorption into the PDMS SPME fibers was found to be the molar enthalpy of sorption, which depended on the molecular size of the hydrocarbons. As the molecular size of the hydrocarbon increased, the molar enthalpies of sorption became more exothermic. Interaction parameters and diffusion coefficients indicated that both n-heptane and n-octane were diffused into the PDMS matrix and localized to form clusters or aggregates, which were responsible for more negative molar entropies of sorption. However, the diffusivities of n-nonane and aromatic probes were limited due to their large molecular size and lack in the structural flexibility, respectively. The molar enthalpies of hydrocarbon sorption were independent of the average molecular weight of PDMS. However, specific retention volumes, interaction parameters, diffusion coefficients, and activation energies of diffusion of the hydrocarbons depended on the molecular weight of PDMS as well as the molecular weights and structures of hydrocarbons, as shown by the results of the Wilcoxon signed-rank test.


Assuntos
Cromatografia Gasosa/métodos , Dimetilpolisiloxanos/química , Hidrocarbonetos/análise , Microextração em Fase Sólida/métodos , Adsorção , Difusão , Peso Molecular , Temperatura
10.
Stat Methods Med Res ; 30(1): 299-315, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32907489

RESUMO

The medical care expenditure is historically an important public health issue, which greatly impacts the government's health policies as well as patients' financial and medical decisions. In population health research, we commonly discretize a numeric attribute to a few ordinal groups to examine population characteristics. Oftentimes, the population marginal mean estimation by the ANOVA approach is inflexible since it uses pre-defined grouping of the covariate. In this paper, we propose a method to estimate the population marginal mean using the B-spline-based regression in a manner of a generalized additive model as an alternative for the ANOVA. Since the medical expenditure is always nonnegative, a Bayesian approach is also implemented for the nonnegative constraint on the marginal mean estimates. The proposed method is flexible to estimate marginal means for user-specified grouping after model fitting in a post-hoc manner, a clear advantage over the ANOVA approach. We show that this method is inferentially superior to the ANOVA through theoretical investigations and an extensive Monte Carlo study. The real data analysis using Medical Expenditure Panel Survey data assisted by some visualization tools demonstrates an applicability of the proposed approach and leads us some interesting observations that may be relevant to public health discussions.


Assuntos
Gastos em Saúde , Política de Saúde , Teorema de Bayes , Humanos , Método de Monte Carlo , Inquéritos e Questionários
11.
Environ Res ; 189: 109935, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32980017

RESUMO

BACKGROUND: In the human body, inorganic arsenic (iAs) is methylated via the one-carbon cycle to form monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA). Lower proportions of iAs and MMA, and higher proportions of DMA in urine indicate efficient methylation; formation of DMA is thought to detoxify iAs and MMA. Studies on folate, vitamin B-12 and iAs methylation yield mixed findings, depending on whether folate and vitamin B-12 were assessed from diet, supplements, or using a blood biomarker. OBJECTIVE: First, to compare the associations of serum concentrations and estimated intake of folate and vitamin B-12 with indicators of iAs methylation. Second, to highlight the implications of these different B-vitamin assessment techniques on the emerging evidence of the impact of dietary modifications on iAs methylation. METHODS: The study was conducted among ~7-year-old children from Montevideo, Uruguay. Serum folate and vitamin B-12 levels were measured on the Horiba ABX Pentra 400 analyzer; urinary arsenic was measured using High-Performance Liquid Chromatography on-line with Inductively Coupled Plasma Mass Spectrometry. Dietary intakes were assessed using the average of two 24-h dietary recalls. Linear regressions assessed the associations of serum levels, and dietary intakes of folate (n = 237) and vitamin B-12 (n = 217) with indicators of iAs methylation. Models were adjusted for age, sex, body mass index, total urinary arsenic, and rice intake. RESULTS: Serum folate and vitamin B-12 levels were above the adequacy threshold for 99% of the participants. No associations were observed between serum folate, serum vitamin B-12, or vitamin B-12 intake and iAs methylation. Folate intake was inversely associated with urinary %MMA [ß (95% confidence interval): -1.04 (-1.89, -0.18)]. CONCLUSION: Additional studies on the role of B-vitamins in iAs methylation are needed to develop a deeper understanding of the implications of assessing folate and vitamin B-12 intake compared to the use of biomarkers. Where possible, both methods should be employed because they reflect different exposure windows and inherent measurement error, and if used individually, will likely continue to contribute to lack of consensus.


Assuntos
Arsênio , Arsenicais , Arsênio/análise , Criança , Ingestão de Alimentos , Exposição Ambiental , Ácido Fólico , Humanos , Metilação , Pesquisa , Uruguai , Vitamina B 12 , Vitaminas
12.
J Chromatogr A ; 1627: 461405, 2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823110

RESUMO

This study focused on the measurements and validity of relative distribution constants of vaporized hydrocarbons between air and polydimethylsiloxane (PDMS) using commercially available capillary columns. Capillary column gas chromatography (CCGC) measurements, using two columns containing a PDMS stationary phase with different film thicknesses, were conducted to determine the relative distribution constants of n-heptane, toluene, n-octane, p-xylene, n-nonane, and 1,2,4-trimethylbenzene between air and PDMS at 90 and 120 °C. To validate the accuracy of the relative distribution constants via CCGC, the compositions of three headspace samples containing different amounts of hydrocarbons were calculated using the relative distribution constants via CCGC and extracted amounts via PDMS solid phase microextraction (SPME) at 90 and 120 °C. It was found that calculated hydrocarbon compositions of headspace samples were comparable to true headspace hydrocarbon compositions via direct vapor analysis, with an average absolute relative error of 3.2%. Our results indicate that CCGC is an alternative method that can provide a reliable and convenient method to determine the relative distribution constants of various hydrocarbons between air and PDMS for quantitative chemical analysis of headspace.


Assuntos
Ar , Dimetilpolisiloxanos/química , Hidrocarbonetos/análise , Cromatografia de Fase Reversa , Hidrocarbonetos/química , Microextração em Fase Sólida , Volatilização
13.
Environ Int ; 142: 105883, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32599352

RESUMO

OBJECTIVE: Arsenic is a known childhood neurotoxicant, but its neurotoxicity at low exposure levels is still not well established. The aim of our cross-sectional study was to test the association between low-level arsenic exposure and executive functions (EF) among children in Montevideo. We also assessed effect modification by arsenic methylation capacity, a susceptibility factor for the health effects of arsenic, and by B-vitamin intake, which impacts arsenic methylation. METHODS: Arsenic exposure was assessed as the specific gravity-adjusted sum of urinary arsenic metabolites (U-As) among 255 ~ 7 year-old children, and methylation capacity as the proportion of urinary monomethylarsonic acid (%MMA). Arsenic concentrations from kitchen water samples at participants' homes were assessed. B-vitamin intake was calculated from the average of two 24-hour dietary recalls. EF was measured using three tests from the Cambridge Neuropsychological Test Automated Battery- Stockings of Cambridge (SOC), Intra-dimensional/extra-dimensional shift task (IED), and Spatial Span (SSP). Generalized linear models assessed the association between U-As and EF measures; models were adjusted for age, sex, maternal education, possessions score, Home Observation for Measurement of the Environment Inventory score, season, and school clusters. Additional analyses were conducted to address issues of residual confounding and sample size. A "B-vitamin index" was calculated using principal component analysis. Effect modification by the index and urinary %MMA was assessed in strata split at the respective medians of these variables. RESULTS: The median (range) U-As and water arsenic levels were 9.9 µg/L (2.2, 47.7) and 0.45 µg/L (0.1, 18.9) respectively, indicating that exposure originated mainly from other sources. U-As was inversely associated with the number of stages completed (ß = -0.02; 95% CI: -0.03, -0.002) and pre-executive shift errors (ß = -0.08; 95% CI: -0.14, -0.02) of the IED task, and span length of the SSP task (ß = -0.01; 95% CI: -0.02, -0.004). There was no clear pattern of effect modification by B-vitamin intake or urinary %MMA. CONCLUSION: Low-level arsenic exposure may adversely affect executive function among children but additional, including longitudinal, studies are necessary to confirm these findings.


Assuntos
Arsênio , Arsenicais , Arsênio/análise , Criança , Estudos Transversais , Exposição Ambiental , Função Executiva , Humanos , Instituições Acadêmicas , Uruguai
14.
J Biopharm Stat ; 30(4): 704-720, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32129135

RESUMO

Estimating the area under a curve (AUC) is an important subject in many fields of medicine and science. The regression model using B-spline functions provides flexibility in curve fitting, making it suitable for AUC estimation with various types of nonlinear trends. Despite the versatility of the B-spline approach, comprehensive discussions regarding relevant AUC estimation techniques using B-spline functions and their comparison with existing methods cannot be found in extant literature. In this paper, we investigate AUC estimation using B-spline regression and B-spline regression with several penalties, as well as discuss corresponding inferences. We carry out an extensive Monte Carlo study to evaluate the performance of the proposed methods in various realistic pharmacokinetics and analytical chemistry data settings. We show that the proposed methods provide robust and reliable AUC estimation regardless of different types of nonlinear models from scientific and medical research areas. Our proposed method is appropriate for general AUC estimation since it does not require nonlinear model specifications and inference techniques corresponding to the specified model.


Assuntos
Química Analítica/estatística & dados numéricos , Farmacocinética , Projetos de Pesquisa/estatística & dados numéricos , Animais , Área Sob a Curva , Simulação por Computador , Interpretação Estatística de Dados , Humanos , Modelos Estatísticos , Método de Monte Carlo , Análise de Regressão
15.
Surgery ; 167(5): 821-828, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32067784

RESUMO

BACKGROUND: The Revised Trauma Score is the standard physiologic injury severity indicator used in trauma research and quality control. Shock index, peripheral oxygen saturation, and temperature have emerged as strong predictors for mortality and morbidity. We hypothesized that replacing systolic blood pressure and respiratory rate with age-adjusted shock index and peripheral oxygen saturation and adding temperature would generate a more accurate model, valid across all ages. METHODS: This is a retrospective database analysis using children and adults from the National Trauma Data Bank for years 2011 to 2015. Glasgow Coma Scale, systolic blood pressure, heart rate, respiratory rate, peripheral oxygen saturation, temperature, and shock index (calculated as heart rate/systolic blood pressure) were used as predictor variables, alone or in combination, in logistic models with survival as primary outcome. Bayesian information criterion and area under the receiver operator characteristic curve were used to compare models' performances. To adjust for age, models tested on the entire population (children and adults) used Z-scores derived on age-based homogenous intervals rather than the raw value. RESULTS: The analysis included 283,724 pediatric and 1,555,478 adult patients. Overall mortality was 0.7% and 2.7%, respectively. The Glasgow Coma Scale + shock index + peripheral oxygen saturation + temperature model outperformed the revised trauma score in both adults (Bayesian information criterion 296,345.94 vs 298,494.72; area under the receiver operator characteristic curve 0.831 vs 0.809, P < .001) and children (Bayesian information criterion 12,251.48 vs 12,283.48; area under the receiver operator characteristic curve 0.974 vs 0.968, P = .05) cohorts. On the merged (children and adults) cohort the Glasgow Coma Scale + Z-scores derived on age-based homogenous intervals + peripheral oxygen saturation + temperature model outperformed the Revised Trauma Score (Bayesian information criterion 313,814.78 vs 317,781.31; area under the receiver operator characteristic curve 0.852 vs 0.809, P < .001). CONCLUSIONS: Replacing systolic blood pressure and respiratory rate with shock index and peripheral oxygen saturation in the Revised Trauma Score model and adding temperature generated a more accurate model in both children and adults. Adjusting shock index for age rendered the model accurate across all ages. Calibration on population-derived nomograms of vital signs would further increase the model's accuracy and precision.


Assuntos
Consumo de Oxigênio , Choque/diagnóstico , Choque/epidemiologia , Ferimentos e Lesões/diagnóstico , Ferimentos e Lesões/epidemiologia , Biomarcadores , Bases de Dados Factuais , Feminino , Escala de Coma de Glasgow , Humanos , Masculino , Curva ROC , Estudos Retrospectivos , Índice de Gravidade de Doença , Choque/etiologia , Choque/metabolismo , Temperatura , Índices de Gravidade do Trauma , Ferimentos e Lesões/etiologia , Ferimentos e Lesões/metabolismo
16.
J Nutr ; 150(5): 1223-1229, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31913474

RESUMO

BACKGROUND: Detoxification of inorganic arsenic (iAs) occurs when it methylates to form monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA). Lower proportions of urinary iAs and MMA, and higher proportions of DMA indicate efficient methylation. The role of B-vitamins in iAs methylation in children with low-level arsenic exposure is understudied. OBJECTIVES: Our study objective was to assess the association between B-vitamin intake and iAs methylation in children with low-level arsenic exposure (<50 µg/L in water; urinary arsenic 5-50 µg/L). METHODS: We conducted a cross-sectional study in 290 ∼7-y-old children in Montevideo. Intake of thiamin, riboflavin, niacin, vitamin B-6, and vitamin B-12 was calculated by averaging 2 nonconsecutive 24-h recalls. Total urinary arsenic concentration was measured as the sum of urinary iAs, MMA, and DMA, and adjusted for urinary specific gravity; iAs methylation was measured as urinary percentage As, percentage MMA, and percentage DMA. Arsenic concentrations from household water sources were assessed. Linear regressions tested the relationships between individual energy-adjusted B-vitamins and iAs methylation. RESULTS: Median (range) arsenic concentrations in urine and water were 9.9 (2.2-48.7) and 0.45 (0.1-18.9) µg/L, respectively. The median (range) of urinary percentage iAs, percentage MMA, and percentage DMA was 10.6% (0.0-33.8), 9.7% (2.6-24.8), and 79.1% (58.5-95.4), respectively. The median (range) intake levels of thiamin, riboflavin, niacin, and vitamin B-6 were 0.81 (0.19-2.56), 1.0 (0.30-2.24), 8.6 (3.5-23.3), and 0.67 (0.25-1.73) mg/1000 kcal, respectively, whereas those of folate and vitamin B-12 were 216 (75-466) and 1.7 (0.34-8.3) µg/1000 kcal, respectively. Vitamin B-6 intake was inversely associated with urinary percentage MMA (ß = -1.60; 95% CI: -3.07, -0.15). No other statistically significant associations were observed. CONCLUSIONS: Although vitamin B-6 intake was inversely associated with urinary percentage MMA, our findings suggest limited support for a relation between B-vitamin intake and iAs methylation in children exposed to low-level arsenic.


Assuntos
Arsênio/metabolismo , Dieta , Exposição Ambiental , Vitamina B 6/administração & dosagem , Arsênio/análise , Arsênio/urina , Arsenicais/urina , Ácido Cacodílico/urina , Criança , Estudos Transversais , Ingestão de Energia , Feminino , Humanos , Inativação Metabólica/efeitos dos fármacos , Masculino , Metilação , Niacina/administração & dosagem , Riboflavina/administração & dosagem , Tiamina/administração & dosagem , Uruguai , Vitamina B 12/administração & dosagem , Água/química
17.
Int J Hyg Environ Health ; 223(1): 124-131, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31588016

RESUMO

OBJECTIVES: Millions of children globally, including the U.S., are exposed to low levels of arsenic from water and food. Arsenic is a known neurotoxicant at high levels but its effects at lower exposure levels are understudied. Arsenic methylation capacity, influenced by B-vitamin intake and status, potentially influences arsenic toxicity. In a cross-secitonal study of 5-8 year-old children from Montevideo, we assessed the relationship between urinary arsenic (U-As) and academic achievement, and tested for effect modification by B-vitamin intake, status, and arsenic methylation capacity. METHODS: Broad math and reading scores were calculated based on six subtests (calculation, math facts fluency, applied problems, sentence reading fluency, letter word identification, passage comprehension) from the Woodcock-Muñoz Achievement Battery. B-vitamin intake was assessed from two non-consecutive 24-h dietary recalls, serum folate and vitamin B-12 levels were measured in a subset of participants. Arsenic methylation capacity was measured as the proportion of urinary monomethylarsonic acid (%MMA). Multiple imputation using chained equations was conducted to account for missing covariate and exposure data. Ordinal regressions assessed associations between U-As and achievement score tertiles in the complete case and imputed samples. A "B-vitamin index" was calculated using principal component analysis. Interactions by urinary %MMA and the B-vitamin index were assessed. RESULTS: Median specific gravity adjusted U-As was 11.7 µg/L (range: 2.6, 50.1). We found no association between U-As and broad math and reading scores, nor effect modification by %MMA or B-vitamins. CONCLUSION: At low-levels of exposure, U-As does not appear to affect children's academic achievement.


Assuntos
Sucesso Acadêmico , Arsênio/metabolismo , Exposição Ambiental/estatística & dados numéricos , Complexo Vitamínico B/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Metilação , Uruguai
18.
BMC Public Health ; 19(1): 647, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138168

RESUMO

BACKGROUND: Handwashing prevalence in schools in Kenya is low due to lack of access to water and soap and lack of drive for handwashing. Soapy water made from detergent powder is an inexpensive alternative to bar soap and disgust and social norms change can be powerful drivers of handwashing, but their effectiveness has not been assessed in school setting. In Kenyan public schools, we evaluated an equipment-behavior change intervention's effect on handwashing outcomes. We also monitored functionality of the Povu Poa prototypes to identify design improvements necessary for continued high usage in institutional settings. METHODS: The intervention included the "Povu Poa", a new type of handwashing station that dispensed foaming soap and rinse water, combined with school-wide behavior change promotion based on disgust and social norms. In this stepped-wedge cluster-randomized trial, we randomly selected 30 schools and divided them into 3 groups of 10. Following baseline data collection, we delivered the intervention sequentially (Group 1: 3-5 weeks after baseline; Group 2: 6-8 weeks; Group 3: 19-24 weeks). We observed outcomes [1] availability of handwashing materials at handwashing places, and; 2) observed handwashing behavior after toilet use among schoolchildren) at baseline and in three follow-up rounds. We compared the outcomes between schools that had received the intervention and schools that had not yet received the intervention. RESULTS: Water and soap/soapy water were available at 2% of school visits before intervention, and at 42% of school visits after intervention.. Before intervention, we observed handwashing with water after 11% of 461 toilet use events; no one was observed to wash hands with soap/soapy water. After intervention, we observed handwashing after 62% of 383 toilet use events (PR = 5.96, 95% CI = 3.02, 11.76) and handwashing with soap/soapy water after 26% of events (PR incalculable). Foaming soap dispenser caps were cracked in 31% of all observations, but were typically still functional. CONCLUSIONS: Our combined equipment-behavior intervention increased availability of handwashing materials and improved the compliance with handwashing after using the toilet, but handwashing with soap was still rare. Equipment durability must be improved for deployment in schools at scale. American Economic Association's Registry for Randomized Controlled Trials; Trial Registry Number (TRN): AEARCTR-0000662; Date of Registry: April 14, 2015.


Assuntos
Desinfecção das Mãos , Serviços de Saúde Escolar , Sabões/provisão & distribuição , Estudantes/psicologia , Abastecimento de Água , Criança , Asco , Feminino , Humanos , Quênia , Masculino , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , Instituições Acadêmicas , Normas Sociais , Estudantes/estatística & dados numéricos
19.
J Neurol Sci ; 400: 188-193, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30981123

RESUMO

BACKGROUND/AIMS: Prostate specific antigen (PSA) is regulated by steroid hormones, such as testosterone, the serum levels of which are altered in patients with Alzheimer's disease (AD).This pilot study compared serum levels of the free (f) PSA between AD, mild cognitive impairment (MCI), and control subjects, and evaluated the relationship between fPSA serum levels and cognitive assessment tests and neuroimaging data. In addition, in a subgroup of AD patients, we correlated fPSA serum levels with the existing data on serum levels of amyloid-beta (Aß), and iron-related proteins, including hepcidin and ferritin. METHODS: Frozen serum samples from the Oregon Tissue Bank were used to measure serum levels of fPSA using enzyme-linked immunosorbent assay. RESULTS: fPSA serum levels calculated as median ±â€¯SD were higher in AD males (663.6 ±â€¯821.0 pg/ml) compared to control males (152.0 ±â€¯207.0 pg/ml), p = 0.003. A similar Pattern emerged when comparing MCI males (310.7 ±â€¯367.0 pg/ml) to control males (P = 0.02). Correlation studies showed a significant association between fPSA and CDR (r = 0.56, P = 0.006) and CDR-SOB (r = 0.54, P = 0.009) in AD males. CONCLUSION: Additional studies in a larger cohort are required for determining whether fPSA can be used as biomarker of AD disease progression and whether it has the potential to identify male subjects at risk of AD dementia.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/sangue , Disfunção Cognitiva/diagnóstico , Antígeno Prostático Específico/sangue , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Biomarcadores/sangue , Disfunção Cognitiva/psicologia , Humanos , Masculino , Pessoa de Meia-Idade
20.
J Chromatogr A ; 1594: 149-159, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-30738614

RESUMO

The adsorption of hydrocarbons present in gasoline residues on household materials was investigated via inverse gas chromatography (IGC). A series of hydrocarbons (n-heptane, n-octane, n-nonane, toluene, p-xylene, and 1,2,4-trimethylbenzene) and three household materials (carpet fibers, cotton fabric, and cardboard) were selected in this work. IGC measurements using columns packed with these household materials were conducted to obtain molar enthalpies of adsorption of the selected hydrocarbons over the temperature range of 40 to 70 °C. Adsorption isotherms and Henry's law solubility coefficients (S) were also determined at 40 °C. Results from our IGC measurements revealed that molar enthalpies of adsorption, adsorption isotherms, and solubility coefficients were largely dependent upon the structures and size of hydrocarbons and the choice of solid substrates. Measured molar enthalpies of adsorption became more exothermic with increasing size of hydrocarbons, ranging from -23.4 to -40.9 kJ/mol for carpet fibers, -36.2 to -48.2 kJ/mol for cotton fabric, and -30.1 to -52.5 kJ/mol for cardboard. From the adsorption isotherms and the measured retention times as a function of the injection amount, the adsorption affinity of hydrocarbons to the carpet fibers was found to be weaker than the affinity between hydrocarbon molecules, producing relatively lower solubility coefficients for all hydrocarbons than those measured on cotton fabric and cardboard. However, the adsorption affinities of hydrocarbons to both cotton fabric and cardboard were much stronger with increased solubility coefficients presumably due to the diffusion and dispersion of hydrocarbons through solid substrates. In particular, solubility coefficients of three aromatics on cardboard were significantly larger than those measured on carpet fibers and cotton fabric. This might be responsible for previously reported enhanced persistence of gasoline residues spiked on cardboard.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Gasosa , Gasolina , Utensílios Domésticos , Hidrocarbonetos/análise , Papel , Têxteis , Adsorção
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