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1.
Nature ; 604(7906): 517-524, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35418684

RESUMEN

The rates and patterns of somatic mutation in normal tissues are largely unknown outside of humans1-7. Comparative analyses can shed light on the diversity of mutagenesis across species, and on long-standing hypotheses about the evolution of somatic mutation rates and their role in cancer and ageing. Here we performed whole-genome sequencing of 208 intestinal crypts from 56 individuals to study the landscape of somatic mutation across 16 mammalian species. We found that somatic mutagenesis was dominated by seemingly endogenous mutational processes in all species, including 5-methylcytosine deamination and oxidative damage. With some differences, mutational signatures in other species resembled those described in humans8, although the relative contribution of each signature varied across species. Notably, the somatic mutation rate per year varied greatly across species and exhibited a strong inverse relationship with species lifespan, with no other life-history trait studied showing a comparable association. Despite widely different life histories among the species we examined-including variation of around 30-fold in lifespan and around 40,000-fold in body mass-the somatic mutation burden at the end of lifespan varied only by a factor of around 3. These data unveil common mutational processes across mammals, and suggest that somatic mutation rates are evolutionarily constrained and may be a contributing factor in ageing.


Asunto(s)
Longevidad , Tasa de Mutación , Animales , Humanos , Longevidad/genética , Mamíferos/genética , Mutagénesis/genética , Mutación
2.
Nature ; 597(7876): 387-392, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34433963

RESUMEN

Starting from the zygote, all cells in the human body continuously acquire mutations. Mutations shared between different cells imply a common progenitor and are thus naturally occurring markers for lineage tracing1,2. Here we reconstruct extensive phylogenies of normal tissues from three adult individuals using whole-genome sequencing of 511 laser capture microdissections. Reconstructed embryonic progenitors in the same generation of a phylogeny often contribute to different extents to the adult body. The degree of this asymmetry varies between individuals, with ratios between the two reconstructed daughter cells of the zygote ranging from 60:40 to 93:7. Asymmetries pervade subsequent generations and can differ between tissues in the same individual. The phylogenies resolve the spatial embryonic patterning of tissues, revealing contiguous patches of, on average, 301 crypts in the adult colonic epithelium derived from a most recent embryonic cell and also a spatial effect in brain development. Using data from ten additional men, we investigated the developmental split between soma and germline, with results suggesting an extraembryonic contribution to primordial germ cells. This research demonstrates that, despite reaching the same ultimate tissue patterns, early bottlenecks and lineage commitments lead to substantial variation in embryonic patterns both within and between individuals.


Asunto(s)
Linaje de la Célula/genética , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Desarrollo Embrionario/genética , Mutación , Encéfalo/metabolismo , Cromosomas Humanos Y/genética , Células Clonales/metabolismo , Mutación de Línea Germinal/genética , Humanos , Masculino , Mosaicismo , Especificidad de Órganos/genética , Polimorfismo de Nucleótido Simple/genética
3.
Nature ; 593(7859): 405-410, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33911282

RESUMEN

Somatic mutations drive the development of cancer and may contribute to ageing and other diseases1,2. Despite their importance, the difficulty of detecting mutations that are only present in single cells or small clones has limited our knowledge of somatic mutagenesis to a minority of tissues. Here, to overcome these limitations, we developed nanorate sequencing (NanoSeq), a duplex sequencing protocol with error rates of less than five errors per billion base pairs in single DNA molecules from cell populations. This rate is two orders of magnitude lower than typical somatic mutation loads, enabling the study of somatic mutations in any tissue independently of clonality. We used this single-molecule sensitivity to study somatic mutations in non-dividing cells across several tissues, comparing stem cells to differentiated cells and studying mutagenesis in the absence of cell division. Differentiated cells in blood and colon displayed remarkably similar mutation loads and signatures to their corresponding stem cells, despite mature blood cells having undergone considerably more divisions. We then characterized the mutational landscape of post-mitotic neurons and polyclonal smooth muscle, confirming that neurons accumulate somatic mutations at a constant rate throughout life without cell division, with similar rates to mitotically active tissues. Together, our results suggest that mutational processes that are independent of cell division are important contributors to somatic mutagenesis. We anticipate that the ability to reliably detect mutations in single DNA molecules could transform our understanding of somatic mutagenesis and enable non-invasive studies on large-scale cohorts.


Asunto(s)
Células Sanguíneas/metabolismo , Diferenciación Celular/genética , Análisis Mutacional de ADN/métodos , Músculo Liso/metabolismo , Mutación , Neuronas/metabolismo , Imagen Individual de Molécula/métodos , Células Madre/metabolismo , Enfermedad de Alzheimer/genética , Células Sanguíneas/citología , División Celular , Estudios de Cohortes , Colon/citología , Epitelio/metabolismo , Granulocitos/citología , Granulocitos/metabolismo , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Músculo Liso/citología , Mutagénesis , Tasa de Mutación , Neuronas/citología , Células Madre/citología
4.
BMC Med Res Methodol ; 24(1): 88, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622506

RESUMEN

BACKGROUND: The analysis of dental caries has been a major focus of recent work on modeling dental defect data. While a dental caries focus is of major importance in dental research, the examination of developmental defects which could also contribute at an early stage of dental caries formation, is also of potential interest. This paper proposes a set of methods which address the appearance of different combinations of defects across different tooth regions. In our modeling we assess the linkages between tooth region development and both the type of defect and associations with etiological predictors of the defects which could be influential at different times during the tooth crown development. METHODS: We develop different hierarchical model formulations under the Bayesian paradigm to assess exposures during primary central incisor (PMCI) tooth development and PMCI defects. We evaluate the Bayesian hierarchical models under various simulation scenarios to compare their performance with both simulated dental defect data and real data from a motivating application. RESULTS: The proposed model provides inference on identifying a subset of etiological predictors of an individual defect accounting for the correlation between tooth regions and on identifying a subset of etiological predictors for the joint effect of defects. Furthermore, the model provides inference on the correlation between the regions of the teeth as well as between the joint effect of the developmental enamel defects and dental caries. Simulation results show that the proposed model consistently yields steady inferences in identifying etiological biomarkers associated with the outcome of localized developmental enamel defects and dental caries under varying simulation scenarios as deemed by small mean square error (MSE) when comparing the simulation results to real application results. CONCLUSION: We evaluate the proposed model under varying simulation scenarios to develop a model for multivariate dental defects and dental caries assuming a flexible covariance structure that can handle regional and joint effects. The proposed model shed new light on methods for capturing inclusive predictors in different multivariate joint models under the same covariance structure and provides a natural extension to a nested hierarchical model.


Asunto(s)
Caries Dental , Incisivo , Niño , Humanos , Teorema de Bayes , Diente Primario , Prevalencia , Esmalte Dental
5.
BMC Med Res Methodol ; 24(1): 14, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38243198

RESUMEN

BACKGROUND: Dengue is a mosquito-borne disease that causes over 300 million infections worldwide each year with no specific treatment available. Effective surveillance systems are needed for outbreak detection and resource allocation. Spatial cluster detection methods are commonly used, but no general guidance exists on the most appropriate method for dengue surveillance. Therefore, a comprehensive study is needed to assess different methods and provide guidance for dengue surveillance programs. METHODS: To evaluate the effectiveness of different cluster detection methods for dengue surveillance, we selected and assessed commonly used methods: Getis Ord [Formula: see text], Local Moran, SaTScan, and Bayesian modeling. We conducted a simulation study to compare their performance in detecting clusters, and applied all methods to a case study of dengue surveillance in Thailand in 2019 to further evaluate their practical utility. RESULTS: In the simulation study, Getis Ord [Formula: see text] and Local Moran had similar performance, with most misdetections occurring at cluster boundaries and isolated hotspots. SaTScan showed better precision but was less effective at detecting inner outliers, although it performed well on large outbreaks. Bayesian convolution modeling had the highest overall precision in the simulation study. In the dengue case study in Thailand, Getis Ord [Formula: see text] and Local Moran missed most disease clusters, while SaTScan was mostly able to detect a large cluster. Bayesian disease mapping seemed to be the most effective, with adaptive detection of irregularly shaped disease anomalies. CONCLUSIONS: Bayesian modeling showed to be the most effective method, demonstrating the best accuracy in adaptively identifying irregularly shaped disease anomalies. In contrast, SaTScan excelled in detecting large outbreaks and regular forms. This study provides empirical evidence for the selection of appropriate tools for dengue surveillance in Thailand, with potential applicability to other disease control programs in similar settings.


Asunto(s)
Dengue , Animales , Humanos , Dengue/diagnóstico , Dengue/epidemiología , Tailandia/epidemiología , Teorema de Bayes , Análisis por Conglomerados , Brotes de Enfermedades/prevención & control , Toma de Decisiones
6.
Caries Res ; 58(1): 30-38, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37918363

RESUMEN

INTRODUCTION: Localized non-inheritable developmental defects of tooth enamel (DDE) are classified as enamel hypoplasia (EH), opacity (OP), and post-eruptive breakdown (PEB) using the enamel defects index. To better understand the etiology of DDE, we assessed the linkages amongst exposome variables for these defects during the specific time duration for enamel mineralization of the human primary maxillary central incisor enamel crowns. In general, these two teeth develop between 13 and 14 weeks in utero and 3-4 weeks' postpartum of a full-term delivery, followed by tooth eruption at about 1 year of age. METHODS: We utilized existing datasets for mother-child dyads that encompassed 12 weeks' gestation through birth and early infancy, and child DDE outcomes from digital images of the erupted primary maxillary central incisor teeth. We applied a Bayesian modeling paradigm to assess the important predictors of EH, OP, and PEB. RESULTS: The results of Gibbs variable selection showed a key set of predictors: mother's prepregnancy body mass index (BMI); maternal serum concentrations of calcium and phosphorus at gestational week 28; child's gestational age; and both mother's and child's functional vitamin D deficiency (FVDD). In this sample of healthy mothers and children, significant predictors for OP included the child having a gestational period >36 weeks and FVDD at birth, and for PEB included a mother's prepregnancy BMI <21.5 and higher serum phosphorus concentration at week 28. CONCLUSION: In conclusion, our methodology and results provide a roadmap for assessing timely biomarker measures of exposures during specific tooth development to better understand the etiology of DDE for future prevention.


Asunto(s)
Hipoplasia del Esmalte Dental , Esmalte Dental , Recién Nacido , Femenino , Humanos , Incisivo , Teorema de Bayes , Hipoplasia del Esmalte Dental/etiología , Prevalencia , Fósforo , Diente Primario
7.
Pediatr Cardiol ; 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762577

RESUMEN

Cardiac index (CI) may be derived from the Fick method, using measured or estimated oxygen consumption (VO2), or from thermodilution. In children, LaFarge VO2 estimates correlate poorly with measured VO2 values. In a large adult cohort, there was only modest correlation between estimated Fick CI (eFick CI) and thermodilution CI (TDCI). We evaluated the extent of agreement between eFick CI using LaFarge estimates of VO2 and TDCI in a pediatric cohort. A retrospective, single-center chart review of patients 3-18 years of age who underwent cardiac catheterization with documented eFick CI and TDCI from 2004 to 2020 included 201 catheterizations from 161 unique patients. The mean patient age at catheterization was 12.2y (SD 4.4y). The most frequent diagnosis was cardiomyopathy, followed by congenital heart disease and pulmonary hypertension. TDCI and eFick CI differed by > 20% in 49% of catheterizations. eFick CI systematically exceeded TDCI by a mean percentage difference of 24% (SD 31%). Higher mean CI ((eFick CI + TDCI)/2) and older age were predictive of greater percent difference between eFick CI and TDCI. For each increase in mean CI by 1.0 L/min/m2, the expected percent difference in CI increased by 9.9% (p < 0.001). In pediatric patients undergoing cardiac catheterization, eFick CI with LaFarge VO2 systematically exceeds TDCI. The difference between methods is frequently > 20%, which may have clinically significant implications. Discrepancies between eFick CI and TDCI increase at higher mean CI.

8.
Pediatr Cardiol ; 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38822853

RESUMEN

We present the clinical course of an 8-month-old infant with a giant cutaneous hemangioma resulting in high-output heart failure and pulmonary hypertension. The lesion was successfully embolized and excised, with rapid resolution of heart failure and improvement in pulmonary hypertension.

9.
Br J Cancer ; 129(7): 1119-1125, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37537254

RESUMEN

BACKGROUND: An association was observed between an inflammation-related risk score (IRRS) and worse overall survival (OS) among a cohort of mostly White women with invasive epithelial ovarian cancer (EOC). Herein, we evaluated the association between the IRRS and OS among Black women with EOC, a population with higher frequencies of pro-inflammatory exposures and worse survival. METHODS: The analysis included 592 Black women diagnosed with EOC from the African American Cancer Epidemiology Study (AACES). Cox proportional hazards models were used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) for the association of the IRRS and OS, adjusting for relevant covariates. Additional inflammation-related exposures, including the energy-adjusted Dietary Inflammatory Index (E-DIITM), were evaluated. RESULTS: A dose-response trend was observed showing higher IRRS was associated with worse OS (per quartile HR: 1.11, 95% CI: 1.01-1.22). Adding the E-DII to the model attenuated the association of IRRS with OS, and increasing E-DII, indicating a more pro-inflammatory diet, was associated with shorter OS (per quartile HR: 1.12, 95% CI: 1.02-1.24). Scoring high on both indices was associated with shorter OS (HR: 1.54, 95% CI: 1.16-2.06). CONCLUSION: Higher levels of inflammation-related exposures were associated with decreased EOC OS among Black women.


Asunto(s)
Inflamación , Neoplasias Ováricas , Humanos , Femenino , Inflamación/epidemiología , Inflamación/complicaciones , Factores de Riesgo , Dieta , Carcinoma Epitelial de Ovario/epidemiología , Carcinoma Epitelial de Ovario/complicaciones , Estudios de Cohortes
10.
BMC Med ; 21(1): 309, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37582755

RESUMEN

BACKGROUND: Measurement of multimorbidity in research is variable, including the choice of the data source used to ascertain conditions. We compared the estimated prevalence of multimorbidity and associations with mortality using different data sources. METHODS: A cross-sectional study of SAIL Databank data including 2,340,027 individuals of all ages living in Wales on 01 January 2019. Comparison of prevalence of multimorbidity and constituent 47 conditions using data from primary care (PC), hospital inpatient (HI), and linked PC-HI data sources and examination of associations between condition count and 12-month mortality. RESULTS: Using linked PC-HI compared with only HI data, multimorbidity was more prevalent (32.2% versus 16.5%), and the population of people identified as having multimorbidity was younger (mean age 62.5 versus 66.8 years) and included more women (54.2% versus 52.6%). Individuals with multimorbidity in both PC and HI data had stronger associations with mortality than those with multimorbidity only in HI data (adjusted odds ratio 8.34 [95% CI 8.02-8.68] versus 6.95 (95%CI 6.79-7.12] in people with ≥ 4 conditions). The prevalence of conditions identified using only PC versus only HI data was significantly higher for 37/47 and significantly lower for 10/47: the highest PC/HI ratio was for depression (14.2 [95% CI 14.1-14.4]) and the lowest for aneurysm (0.51 [95% CI 0.5-0.5]). Agreement in ascertainment of conditions between the two data sources varied considerably, being slight for five (kappa < 0.20), fair for 12 (kappa 0.21-0.40), moderate for 16 (kappa 0.41-0.60), and substantial for 12 (kappa 0.61-0.80) conditions, and by body system was lowest for mental and behavioural disorders. The percentage agreement, individuals with a condition identified in both PC and HI data, was lowest in anxiety (4.6%) and highest in coronary artery disease (62.9%). CONCLUSIONS: The use of single data sources may underestimate prevalence when measuring multimorbidity and many important conditions (especially mental and behavioural disorders). Caution should be used when interpreting findings of research examining individual and multiple long-term conditions using single data sources. Where available, researchers using electronic health data should link primary care and hospital inpatient data to generate more robust evidence to support evidence-based healthcare planning decisions for people with multimorbidity.


Asunto(s)
Multimorbilidad , Medicina Estatal , Humanos , Femenino , Persona de Mediana Edad , Estudios Transversales , Fuentes de Información , Prevalencia , Enfermedad Crónica
11.
Cancer Causes Control ; 34(3): 251-265, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36520244

RESUMEN

PURPOSE: The causes for the survival disparity among Black women with epithelial ovarian cancer (EOC) are likely multi-factorial. Here we describe the African American Cancer Epidemiology Study (AACES), the largest cohort of Black women with EOC. METHODS: AACES phase 2 (enrolled 2020 onward) is a multi-site, population-based study focused on overall survival (OS) of EOC. Rapid case ascertainment is used in ongoing patient recruitment in eight U.S. states, both northern and southern. Data collection is composed of a survey, biospecimens, and medical record abstraction. Results characterizing the survival experience of the phase 1 study population (enrolled 2010-2015) are presented. RESULTS: Thus far, ~ 650 patients with EOC have been enrolled in the AACES. The five-year OS of AACES participants approximates those of Black women in the Surveillance Epidemiology and End Results (SEER) registry who survive at least 10-month past diagnosis and is worse compared to white women in SEER, 49 vs. 60%, respectively. A high proportion of women in AACES have low levels of household income (45% < $25,000 annually), education (51% ≤ high school education), and insurance coverage (32% uninsured or Medicaid). Those followed annually differ from those without follow-up with higher levels of localized disease (28 vs 24%) and higher levels of optimal debulking status (73 vs 67%). CONCLUSION: AACES is well positioned to evaluate the contribution of social determinants of health to the poor survival of Black women with EOC and advance understanding of the multi-factorial causes of the ovarian cancer survival disparity in Black women.


Asunto(s)
Negro o Afroamericano , Carcinoma Epitelial de Ovario , Neoplasias Ováricas , Femenino , Humanos , Carcinoma Epitelial de Ovario/epidemiología , Neoplasias Ováricas/epidemiología , Sistema de Registros , Estados Unidos/epidemiología
12.
Bioinformatics ; 38(4): 1067-1074, 2022 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-34849578

RESUMEN

MOTIVATION: In spite of great success of genome-wide association studies (GWAS), multiple challenges still remain. First, complex traits are often associated with many single nucleotide polymorphisms (SNPs), each with small or moderate effect sizes. Second, our understanding of the functional mechanisms through which genetic variants are associated with complex traits is still limited. To address these challenges, we propose GPA-Tree and it simultaneously implements association mapping and identifies key combinations of functional annotations related to risk-associated SNPs by combining a decision tree algorithm with a hierarchical modeling framework. RESULTS: First, we implemented simulation studies to evaluate the proposed GPA-Tree method and compared its performance with existing statistical approaches. The results indicate that GPA-Tree outperforms existing statistical approaches in detecting risk-associated SNPs and identifying the true combinations of functional annotations with high accuracy. Second, we applied GPA-Tree to a systemic lupus erythematosus (SLE) GWAS and functional annotation data including GenoSkyline and GenoSkylinePlus. The results from GPA-Tree highlight the dysregulation of blood immune cells, including but not limited to primary B, memory helper T, regulatory T, neutrophils and CD8+ memory T cells in SLE. These results demonstrate that GPA-Tree can be a powerful tool that improves association mapping while facilitating understanding of the underlying genetic architecture of complex traits and potential mechanisms linking risk-associated SNPs with complex traits. AVAILABILITY AND IMPLEMENTATION: The GPATree software is available at https://dongjunchung.github.io/GPATree/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Estudio de Asociación del Genoma Completo , Programas Informáticos , Estudio de Asociación del Genoma Completo/métodos , Algoritmos , Simulación por Computador , Polimorfismo de Nucleótido Simple
13.
Am J Obstet Gynecol ; 229(4): 366-376.e8, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37116824

RESUMEN

Ovarian cancer is the fifth leading cause of cancer-associated mortality among US women with survival disparities seen across race, ethnicity, and socioeconomic status, even after accounting for histology, stage, treatment, and other clinical factors. Neighborhood context can play an important role in ovarian cancer survival, and, to the extent to which minority racial and ethnic groups and populations of lower socioeconomic status are more likely to be segregated into neighborhoods with lower quality social, built, and physical environment, these contextual factors may be a critical component of ovarian cancer survival disparities. Understanding factors associated with ovarian cancer outcome disparities will allow clinicians to identify patients at risk for worse outcomes and point to measures, such as social support programs or transportation aid, that can help to ameliorate such disparities. However, research on the impact of neighborhood contextual factors in ovarian cancer survival and in disparities in ovarian cancer survival is limited. This commentary focuses on the following neighborhood contextual domains: structural and institutional context, social context, physical context represented by environmental exposures, built environment, rurality, and healthcare access. The research conducted to date is presented and clinical implications and recommendations for future interventions and studies to address disparities in ovarian cancer outcomes are proposed.


Asunto(s)
Etnicidad , Neoplasias Ováricas , Humanos , Femenino , Factores Socioeconómicos , Clase Social , Neoplasias Ováricas/terapia , Medio Social , Disparidades en Atención de Salud
14.
BMC Med Res Methodol ; 23(1): 182, 2023 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-37568119

RESUMEN

BACKGROUND: Bayesian models have been applied throughout the Covid-19 pandemic especially to model time series of case counts or deaths. Fewer examples exist of spatio-temporal modeling, even though the spatial spread of disease is a crucial factor in public health monitoring. The predictive capabilities of infectious disease models is also important. METHODS: In this study, the ability of Bayesian hierarchical models to recover different parts of the variation in disease counts is the focus. It is clear that different measures provide different views of behavior when models are fitted prospectively. Over a series of time horizons one step predictions have been generated and compared for different models (for case counts and death counts). These Bayesian SIR models were fitted using MCMC at 28 time horizons to mimic prospective prediction. A range of goodness of prediction measures were analyzed across the different time horizons. RESULTS: A particularly important result is that the peak intensity of case load is often under-estimated, while random spikes in case load can be mimicked using time dependent random effects. It is also clear that during the early wave of the pandemic simpler model forms are favored, but subsequently lagged spatial dependence models for cases are favored, even if the sophisticated models perform better overall. DISCUSSION: The models fitted mimic the situation where at a given time the history of the process is known but the future must be predicted based on the current evolution which has been observed. Using an overall 'best' model for prediction based on retrospective fitting of the complete pandemic waves is an assumption. However it is also clear that this case count model is well favored over other forms. During the first wave a simpler time series model predicts case counts better for counties than a spatially dependent one. The picture is more varied for morality. CONCLUSIONS: From a predictive point of view it is clear that spatio-temporal models applied to county level Covid-19 data within the US vary in how well they fit over time and also how well they predict future events. At different times, SIR case count models and also mortality models with cumulative counts perform better in terms of prediction. A fundamental result is that predictive capability of models varies over time and using the same model could lead to poor predictive performance. In addition it is clear that models addressing the spatial context for case counts (i.e. with lagged neighborhood terms) and cumulative case counts for mortality data are clearly better at modeling spatio-temporal data which is commonly available for the Covid-19 pandemic in different areas of the globe.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Teorema de Bayes , Estudios Prospectivos , Pandemias , Estudios Retrospectivos
15.
BMC Med Res Methodol ; 23(1): 62, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36915077

RESUMEN

BACKGROUND: To control emerging diseases, governments often have to make decisions based on limited evidence. The effective or temporal reproductive number is used to estimate the expected number of new cases caused by an infectious person in a partially susceptible population. While the temporal dynamic is captured in the temporal reproduction number, the dominant approach is currently based on modeling that implicitly treats people within a population as geographically well mixed. METHODS: In this study we aimed to develop a generic and robust methodology for estimating spatiotemporal dynamic measures that can be instantaneously computed for each location and time within a Bayesian model selection and averaging framework. A simulation study was conducted to demonstrate robustness of the method. A case study was provided of a real-world application to COVID-19 national surveillance data in Thailand. RESULTS: Overall, the proposed method allowed for estimation of different scenarios of reproduction numbers in the simulation study. The model selection chose the true serial interval when included in our study whereas model averaging yielded the weighted outcome which could be less accurate than model selection. In the case study of COVID-19 in Thailand, the best model based on model selection and averaging criteria had a similar trend to real data and was consistent with previously published findings in the country. CONCLUSIONS: The method yielded robust estimation in several simulated scenarios of force of transmission with computing flexibility and practical benefits. Thus, this development can be suitable and practically useful for surveillance applications especially for newly emerging diseases. As new outbreak waves continue to develop and the risk changes on both local and global scales, our work can facilitate policymaking for timely disease control.


Asunto(s)
COVID-19 , Enfermedades Transmisibles Emergentes , Humanos , COVID-19/epidemiología , Enfermedades Transmisibles Emergentes/epidemiología , Teorema de Bayes , Simulación por Computador , Brotes de Enfermedades/prevención & control
16.
BMC Med Res Methodol ; 23(1): 171, 2023 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-37481553

RESUMEN

BACKGROUND: COVID-19 brought enormous challenges to public health surveillance and underscored the importance of developing and maintaining robust systems for accurate surveillance. As public health data collection efforts expand, there is a critical need for infectious disease modeling researchers to continue to develop prospective surveillance metrics and statistical models to accommodate the modeling of large disease counts and variability. This paper evaluated different likelihoods for the disease count model and various spatiotemporal mean models for prospective surveillance. METHODS: We evaluated Bayesian spatiotemporal models, which are the foundation for model-based infectious disease surveillance metrics. Bayesian spatiotemporal mean models based on the Poisson and the negative binomial likelihoods were evaluated with the different lengths of past data usage. We compared their goodness of fit and short-term prediction performance with both simulated epidemic data and real data from the COVID-19 pandemic. RESULTS: The simulation results show that the negative binomial likelihood-based models show better goodness of fit results than Poisson likelihood-based models as deemed by smaller deviance information criteria (DIC) values. However, Poisson models yield smaller mean square error (MSE) and mean absolute one-step prediction error (MAOSPE) results when we use a shorter length of the past data such as 7 and 3 time periods. Real COVID-19 data analysis of New Jersey and South Carolina shows similar results for the goodness of fit and short-term prediction results. Negative binomial-based mean models showed better performance when we used the past data of 52 time periods. Poisson-based mean models showed comparable goodness of fit performance and smaller MSE and MAOSPE results when we used the past data of 7 and 3 time periods. CONCLUSION: We evaluate these models and provide future infectious disease outbreak modeling guidelines for Bayesian spatiotemporal analysis. Our choice of the likelihood and spatiotemporal mean models was influenced by both historical data length and variability. With a longer length of past data usage and more over-dispersed data, the negative binomial likelihood shows a better model fit than the Poisson likelihood. However, as we use a shorter length of the past data for our surveillance analysis, the difference between the Poisson and the negative binomial models becomes smaller. In this case, the Poisson likelihood shows robust posterior mean estimate and short-term prediction results.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Humanos , Teorema de Bayes , COVID-19/epidemiología , Funciones de Verosimilitud , Pandemias , Estudios Prospectivos , Enfermedades Transmisibles/epidemiología
17.
J Cardiovasc Magn Reson ; 25(1): 61, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37932797

RESUMEN

BACKGROUND: Chronic graft failure and cumulative rejection history in pediatric heart transplant recipients (PHTR) are associated with myocardial fibrosis on endomyocardial biopsy (EMB). Cardiovascular magnetic resonance imaging (CMR) is a validated, non-invasive method to detect myocardial fibrosis via the presence of late gadolinium enhancement (LGE). In adult heart transplant recipients, LGE is associated with increased risk of future adverse clinical events including hospitalization and death. We describe the prevalence, pattern, and extent of LGE on CMR in a cohort of PHTR and its associations with recipient and graft characteristics. METHODS: This was a retrospective study of consecutive PHTR who underwent CMR over a 6-year period at a single center. Two independent reviewers assessed the presence and distribution of left ventricular (LV) LGE using the American Heart Association (AHA) 17-segment model. LGE quantification was performed on studies with visible fibrosis (LGE+). Patient demographics, clinical history, and CMR-derived volumetry and ejection fractions were obtained. RESULTS: Eighty-one CMR studies were performed on 59 unique PHTR. Mean age at CMR was 14.8 ± 6.2 years; mean time since transplant was 7.3 ± 5.0 years. The CMR indication was routine surveillance (without a clinical concern based on laboratory parameters, echocardiography, or cardiac catheterization) in 63% (51/81) of studies. LGE was present in 36% (29/81) of PHTR. In these LGE + studies, patterns included inferoseptal in 76% of LGE + studies (22/29), lateral wall in 41% (12/29), and diffuse, involving > 4 AHA segments, in 21% (6/29). The mean LV LGE burden as a percentage of myocardial mass was 18.0 ± 9.0%. When reviewing only the initial CMR per PHTR (n = 59), LGE + patients were older (16.7 ± 2.9 vs. 12.8 ± 4.6 years, p = 0.001), with greater time since transplant (8.3 ± 5.4 vs. 5.7 ± 3.9 years, p = 0.041). These patients demonstrated higher LV end-systolic volume index (LVESVI) (34.7 ± 11.7 vs. 28.7 ± 6.1 ml/m2, p = 0.011) and decreased LV ejection fraction (LVEF) (56.2 ± 8.1 vs. 60.6 ± 5.3%, p = 0.015). There were no significant differences in history of moderate/severe rejection (p = 0.196) or cardiac allograft vasculopathy (CAV) (p = 0.709). CONCLUSIONS: LV LGE was present in approximately one third of PHTR, more commonly in older patients with longer time since transplantation. Grafts with LGE have lower LVEF. CMR-derived LGE may aid in surveillance of chronic graft failure in PHTR.


Asunto(s)
Cardiomiopatías , Trasplante de Corazón , Adulto , Humanos , Niño , Anciano , Adolescente , Adulto Joven , Medios de Contraste , Volumen Sistólico , Gadolinio , Estudios Retrospectivos , Valor Predictivo de las Pruebas , Fibrosis , Imagen por Resonancia Cinemagnética/métodos
18.
J Hand Surg Am ; 48(6): 533-543, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37115143

RESUMEN

PURPOSE: Surgical treatment of distal radius fractures provides better fracture alignment than closed reduction; however, surgical treatment does not lead to better patient-reported function at 12 months. The aims of this study were to report the radiographic outcomes from the Combined Randomized and Observational Study of Surgery for Fractures In the distal Radius in the Elderly trial, investigate the association between radiographic outcomes and patient-reported function, and explore whether this association was affected by posttreatment complications and direction of malalignment. METHODS: This study used the outcomes of the Combined Randomized and Observational Study of Surgery for Fractures In the distal Radius in the Elderly trial, which is a combined randomized and observational trial that compared volar-locking plate fixation with closed reduction and cast immobilization, to treat distal radius fractures in patients aged ≥60 years. Four radiographic outcomes (dorsal angulation, radial inclination, ulnar variance, and articular step) were reported at the following three time frames: (1) baseline, (2) after treatment, and (3) ≥6 weeks by treatment group. Secondary analysis was correlation of 12-month patient-reported function scores with 6-week radiographic measures for each of four radiographic parameters, and a subgroup analysis was conducted to investigate if this was affected by posttreatment complications. Tertiary analysis investigated if direction of malalignment affected the secondary analysis. RESULTS: We recruited 300 participants (166 randomized and 134 observational); 113 had volar-locking plate fixation, and 187 had closed reduction. There were no between-group differences for each of the four pretreatment radiographic parameters, but there were between-treatment group differences for all four radiographic parameters apart from articular step. We found no association between patient-reported function at 12 months and each of the four radiographic parameters at 6 weeks. This lack of association was unaffected by posttreatment complications and the direction of malalignment. CONCLUSIONS: For patients with wrist fractures aged ≥60 years, final radiographic alignment did not correlate with patient-reported function at 12 months. These findings were not affected by treatment type, and there was no association between radiographic alignment and posttreatment complications. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Asunto(s)
Traumatismos de la Mano , Fracturas del Radio , Fracturas de la Muñeca , Traumatismos de la Muñeca , Anciano , Humanos , Fracturas del Radio/diagnóstico por imagen , Fracturas del Radio/cirugía , Fijación Interna de Fracturas/efectos adversos , Resultado del Tratamiento , Traumatismos de la Muñeca/diagnóstico por imagen , Traumatismos de la Muñeca/cirugía , Traumatismos de la Mano/etiología , Articulación de la Muñeca/diagnóstico por imagen , Articulación de la Muñeca/cirugía , Placas Óseas , Rango del Movimiento Articular
19.
Environ Manage ; 72(2): 294-308, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36881178

RESUMEN

Soil carbon sequestration programmes are a way of offsetting GHG emissions, however, it requires agricultural landholders to be engaged in such initiatives for carbon offsets to occur. Farmer engagement is low in market-based programmes for soil carbon credits in Australia. We interviewed long-term practitioners (n = 25) of rotational grazing in high-rainfall lands of New South Wales, Australia to understand their current social-ecological system (SES) of soil carbon management (SCM). The aim was to identify those components of the SES that motivate them to manage soil carbon and also influence their potential engagement in soil carbon sequestration programmes. Utilising first-tier and second-tier concepts from Ostrom's SES framework, the interview data were coded and identified a total of 51 features that characterised the farmers' SES of SCM. Network analysis of farmer interview data revealed that the current SES of SCM has low connectivity among the SES features (30%). In four workshops with interviewed farmers (n = 2) and invited service providers (n = 2) the 51 features were reviewed and participants decided on the positioning and the interactions between features that were considered to influence SCM into a causal loop diagram. Post-workshop, 10 feedback loops were identified that revealed the different and common perspectives of farmers and service providers on SCM in a consolidated causal loop diagram. Defining the SES relationships for SCM can identify the challenges and needs of stakeholders, particularly farmers, which can then be addressed to achieve local, national and international objectives, such as SCM co-benefits, GHG reduction, carbon sequestration targets and SDGs.


Asunto(s)
Agricultores , Suelo , Humanos , Carbono/análisis , Australia , Agricultura , Ecosistema
20.
Int J Health Geogr ; 20(1): 10, 2021 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-33639940

RESUMEN

BACKGROUND: Diabetes is a public health burden that disproportionately affects military veterans and racial minorities. Studies of racial disparities are inherently observational, and thus may require the use of methods such as Propensity Score Analysis (PSA). While traditional PSA accounts for patient-level factors, this may not be sufficient when patients are clustered at the geographic level and thus important confounders, whether observed or unobserved, vary by geographic location. METHODS: We employ a spatial propensity score matching method to account for "geographic confounding", which occurs when the confounding factors, whether observed or unobserved, vary by geographic region. We augment the propensity score and outcome models with spatial random effects, which are assigned scaled Besag-York-Mollié priors to address spatial clustering and improve inferences by borrowing information across neighboring geographic regions. We apply this approach to a study exploring racial disparities in diabetes specialty care between non-Hispanic black and non-Hispanic white veterans. We construct multiple global estimates of the risk difference in diabetes care: a crude unadjusted estimate, an estimate based solely on patient-level matching, and an estimate that incorporates both patient and spatial information. RESULTS: In simulation we show that in the presence of an unmeasured geographic confounder, ignoring spatial heterogeneity results in increased relative bias and mean squared error, whereas incorporating spatial random effects improves inferences. In our study of racial disparities in diabetes specialty care, the crude unadjusted estimate suggests that specialty care is more prevalent among non-Hispanic blacks, while patient-level matching indicates that it is less prevalent. Hierarchical spatial matching supports the latter conclusion, with a further increase in the magnitude of the disparity. CONCLUSIONS: These results highlight the importance of accounting for spatial heterogeneity in propensity score analysis, and suggest the need for clinical care and management strategies that are culturally sensitive and racially inclusive.


Asunto(s)
Grupos Raciales , Población Blanca , Sesgo , Humanos , Puntaje de Propensión , Análisis Espacial
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