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1.
Bioinformatics ; 40(4)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38514403

RESUMO

MOTIVATION: Due to the link between microglial morphology and function, morphological changes in microglia are frequently used to identify pathological immune responses in the central nervous system. In the absence of pathology, microglia are responsible for maintaining homeostasis, and their morphology can be indicative of how the healthy brain behaves in the presence of external stimuli and genetic differences. Despite recent interest in high throughput methods for morphological analysis, Sholl analysis is still widely used for quantifying microglia morphology via imaging data. Often, the raw data are naturally hierarchical, minimally including many cells per image and many images per animal. However, existing methods for performing downstream inference on Sholl data rely on truncating this hierarchy so rudimentary statistical testing procedures can be used. RESULTS: To fill this longstanding gap, we introduce a parametric hierarchical Bayesian model-based approach for analyzing Sholl data, so that inference can be performed without aggressive reduction of otherwise very rich data. We apply our model to real data and perform simulation studies comparing the proposed method with a popular alternative. AVAILABILITY AND IMPLEMENTATION: Software to reproduce the results presented in this article is available at: https://github.com/vonkaenelerik/hierarchical_sholl. An R package implementing the proposed models is available at: https://github.com/vonkaenelerik/ShollBayes.


Assuntos
Software , Animais , Teorema de Bayes , Simulação por Computador
2.
J Pathol ; 263(3): 386-395, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38801208

RESUMO

While increased DNA damage is a well-described feature of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), it is unclear whether all lineages and all regions of the marrow are homogeneously affected. In this study, we performed immunohistochemistry on formalin-fixed, paraffin-embedded whole-section bone marrow biopsies using a well-established antibody to detect pH2A.X (phosphorylated histone variant H2A.X) that recognizes DNA double-strand breaks. Focusing on TP53-mutated and complex karyotype MDS/AML, we find a greater pH2A.X+ DNA damage burden compared to TP53 wild-type neoplastic cases and non-neoplastic controls. To understand how double-strand breaks vary between lineages and spatially in TP53-mutated specimens, we applied a low-multiplex immunofluorescence staining and spatial analysis protocol to visualize pH2A.X+ cells with p53 protein staining and lineage markers. pH2A.X marked predominantly mid- to late-stage erythroids, whereas early erythroids and CD34+ blasts were relatively spared. In a prototypical example, these pH2A.X+ erythroids were organized locally as distinct colonies, and each colony displayed pH2A.X+ puncta at a synchronous level. This highly coordinated immunophenotypic expression was also seen for p53 protein staining and among presumed early myeloid colonies. Neighborhood clustering analysis showed distinct marrow regions differentially enriched in pH2A.X+/p53+ erythroid or myeloid colonies, indicating spatial heterogeneity of DNA-damage response and p53 protein expression. The lineage and architectural context within which DNA damage phenotype and oncogenic protein are expressed is relevant to current therapeutic developments that leverage macrophage phagocytosis to remove leukemic cells in part due to irreparable DNA damage. © 2024 The Pathological Society of Great Britain and Ireland.


Assuntos
Mutação , Síndromes Mielodisplásicas , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Síndromes Mielodisplásicas/metabolismo , Pessoa de Meia-Idade , Dano ao DNA , Masculino , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/metabolismo , Idoso , Feminino , Quebras de DNA de Cadeia Dupla , Histonas/metabolismo , Histonas/genética , Medula Óssea/patologia , Medula Óssea/metabolismo , Idoso de 80 Anos ou mais , Imuno-Histoquímica
3.
Appl Environ Microbiol ; 90(2): e0183523, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38214516

RESUMO

Even though differences in methodology (e.g., sample volume and detection method) have been shown to affect observed microbial water quality, multiple sampling and laboratory protocols continue to be used for water quality monitoring. Research is needed to determine how these differences impact the comparability of findings to generate best management practices and the ability to perform meta-analyses. This study addresses this knowledge gap by compiling and analyzing a data set representing 2,429,990 unique data points on at least one microbial water quality target (e.g., Salmonella presence and Escherichia coli concentration). Variance partitioning analysis was used to quantify the variance in likelihood of detecting each pathogenic target that was uniquely and jointly attributable to non-methodological versus methodological factors. The strength of the association between microbial water quality and select methodological and non-methodological factors was quantified using conditional forest and regression analysis. Fecal indicator bacteria concentrations were more strongly associated with non-methodological factors than methodological factors based on conditional forest analysis. Variance partitioning analysis could not disentangle non-methodological and methodological signals for pathogenic Escherichia coli, Salmonella, and Listeria. This suggests our current perceptions of foodborne pathogen ecology in water systems are confounded by methodological differences between studies. For example, 31% of total variance in likelihood of Salmonella detection was explained by methodological and/or non-methodological factors, 18% was jointly attributable to both methodological and non-methodological factors. Only 13% of total variance was uniquely attributable to non-methodological factors for Salmonella, highlighting the need for standardization of methods for microbiological water quality testing for comparison across studies.IMPORTANCEThe microbial ecology of water is already complex, without the added complications of methodological differences between studies. This study highlights the difficulty in comparing water quality data from projects that used different sampling or laboratory methods. These findings have direct implications for end users as there is no clear way to generalize findings in order to characterize broad-scale ecological phenomenon and develop science-based guidance. To best support development of risk assessments and guidance for monitoring and managing waters, data collection and methods need to be standardized across studies. A minimum set of data attributes that all studies should collect and report in a standardized way is needed. Given the diversity of methods used within applied and environmental microbiology, similar studies are needed for other microbiology subfields to ensure that guidance and policy are based on a robust interpretation of the literature.


Assuntos
Escherichia coli , Listeria , Microbiologia Ambiental , Salmonella , Alimentos , Microbiologia de Alimentos , Inocuidade dos Alimentos
4.
J Eur Acad Dermatol Venereol ; 38(7): 1364-1372, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38357778

RESUMO

BACKGROUND: Atopic dermatitis (AD) is a chronic skin disease that affects 20% of children worldwide and is associated with low patient-reported quality of life (QoL). Crisaborole (CRIS) and tacrolimus 0.03% (TAC) are Food and Drug Administration (FDA)-approved topical treatments for mild to moderate AD with similar clinical efficacy. Utilization of patient-reported outcomes (PROs) may provide meaningful data on the impact of AD treatments on patients and caregivers. This study used PROs to monitor the impact of crisaborole (CRIS) and tacrolimus 0.03% (TAC) on children with mild/moderate atopic dermatitis (AD) and caregiver burden. METHODS: This open-label study randomized 47 child-caregiver dyads to CRIS or TAC for 12 weeks. Disease severity, child quality of life (QoL), itch, pain interference, anxiety, depression, sleep, caregiver burden and caregiver QoL were assessed at baseline, 6 and 12 weeks. RESULTS: A total of 36 dyads completed the study. Children (mean age = 8.0 ± 3.9 years) had mild baseline AD and were diverse by race (39% white; 36% Black) and gender (53% males). Caregivers were mostly female (78%; mean age = 37 ± 7.6 years). Both arms improved disease severity (Eczema Area and Severity Index) from baseline to 12 weeks (CRIS = -2.4 vs. TAC = -1.9). Within-arm analyses comparing baseline to 12 weeks revealed TAC, but not CRIS, improved all child and caregiver PROs except sleep (all p < 0.05). CONCLUSIONS: Our results demonstrated that topical treatment for 12 weeks was more beneficial than 6 weeks, with TAC improving more PROs than CRIS. Future trials should implement PROs to fully understand the impact of AD treatments.


Assuntos
Compostos de Boro , Compostos Bicíclicos Heterocíclicos com Pontes , Cuidadores , Dermatite Atópica , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Tacrolimo , Humanos , Dermatite Atópica/tratamento farmacológico , Criança , Feminino , Tacrolimo/uso terapêutico , Tacrolimo/administração & dosagem , Masculino , Compostos de Boro/uso terapêutico , Pré-Escolar , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Índice de Gravidade de Doença , Prurido/tratamento farmacológico , Ansiedade , Adolescente , Depressão/tratamento farmacológico , Sono/efeitos dos fármacos , Dor/tratamento farmacológico , Imunossupressores/uso terapêutico
5.
Br J Nutr ; 130(8): 1366-1372, 2023 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36759019

RESUMO

Maternal fish consumption exposes the fetus to beneficial nutrients and potentially adverse neurotoxicants. The current study investigated associations between maternal fish consumption and child neurodevelopmental outcomes. Maternal fish consumption was assessed in the Seychelles Child Development Study Nutrition Cohort 1 (n 229) using 4-day food diaries. Neurodevelopment was evaluated at 9 and 30 months, and 5 and 9 years with test batteries assessing twenty-six endpoints and covering multiple neurodevelopmental domains. Analyses used multiple linear regression with adjustment for covariates known to influence child neurodevelopment. This cohort consumed an average of 8 fish meals/week and the total fish intake during pregnancy was 106·8 (sd 61·9) g/d. Among the twenty-six endpoints evaluated in the primary analysis there was one beneficial association. Children whose mothers consumed larger quantities of fish performed marginally better on the Kaufman Brief Intelligence Test (a test of nonverbal intelligence) at age 5 years (ß 0·003, 95 % CI (0, 0·005)). A secondary analysis dividing fish consumption into tertiles found no significant associations when comparing the highest and lowest consumption groups. In this cohort, where fish consumption is substantially higher than current global recommendations, maternal fish consumption during pregnancy was not beneficially or adversely associated with children's neurodevelopmental outcomes.


Assuntos
Compostos de Metilmercúrio , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Animais , Desenvolvimento Infantil , Seicheles , Estado Nutricional
6.
Clin Chem Lab Med ; 61(7): 1335-1342, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-36698327

RESUMO

OBJECTIVES: Confounding factors, including sex, age, and renal dysfunction, affect high-sensitivity cardiac troponin T (hs-cTnT) concentrations and the acute myocardial infarction (AMI) diagnosis. This study assessed the effects of these confounders through logistic regression models and evaluated the diagnostic performance of an optimized, integrated prediction model. METHODS: This retrospective study included a primary derivation cohort of 18,022 emergency department (ED) patients at a US medical center and a validation cohort of 890 ED patients at a Canadian medical center. Hs-cTnT was measured with 0/3 h sampling. The primary outcome was index AMI diagnosis. Logistic regression models were optimized to predict AMI using delta hs-cTnT and its confounders as covariates. The diagnostic performance of model cutoffs was compared to that of the hs-cTnT delta thresholds. Serial logistic regressions were carried out to evaluate the relationship between covariates. RESULTS: The area under the curve of the best-fitted model was 0.95. The model achieved a 90.0% diagnostic accuracy in the validation cohort. The optimal model cutoff yielded comparable performance (90.5% accuracy) to the optimal sex-specific delta thresholds (90.3% accuracy), with 95.8% agreement between the two diagnostic methods. Serial logistic regressions revealed that delta hs-cTnT played a more predominant role in AMI prediction than its confounders, among which sex is more predictive of AMI (total effect coefficient 1.04) than age (total effect coefficient 0.05) and eGFR (total effect coefficient -0.008). CONCLUSIONS: The integrated prediction model incorporating confounding factors does not outperform hs-cTnT delta thresholds. Sex-specific hs-cTnT delta thresholds remain to provide the highest diagnostic accuracy.


Assuntos
Infarto do Miocárdio , Troponina T , Masculino , Feminino , Humanos , Modelos Logísticos , Estudos Retrospectivos , Canadá , Infarto do Miocárdio/diagnóstico , Biomarcadores
7.
J Appl Microbiol ; 134(10)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37709569

RESUMO

AIMS: While fecal indicator bacteria (FIB) testing is used to monitor surface water for potential health hazards, observed variation in FIB levels may depend on the scale of analysis (SOA). Two decades of citizen science data, coupled with random effects models, were used to quantify the variance in FIB levels attributable to spatial versus temporal factors. METHODS AND RESULTS: Separately, Bayesian models were used to quantify the ratio of spatial to non-spatial variance in FIB levels and identify associations between environmental factors and FIB levels. Separate analyses were performed for three SOA: waterway, watershed, and statewide. As SOA increased (from waterway to watershed to statewide models), variance attributable to spatial sources generally increased and variance attributable to temporal sources generally decreased. While relationships between FIB levels and environmental factors, such as flow conditions (base versus stormflow), were constant across SOA, the effect of land cover was highly dependent on SOA and consistently smaller than the effect of stormwater infrastructure (e.g. outfalls). CONCLUSIONS: This study demonstrates the importance of SOA when developing water quality monitoring programs or designing future studies to inform water management.


Assuntos
Ciência do Cidadão , Qualidade da Água , Monitoramento Ambiental/métodos , Teorema de Bayes , Escherichia coli , Microbiologia da Água , Fezes/microbiologia , Bactérias
8.
Appl Environ Microbiol ; 88(23): e0160022, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36409131

RESUMO

While growers have reported pressures to minimize wildlife intrusion into produce fields through noncrop vegetation (NCV) removal, NCV provides key ecosystem services. To model food safety and environmental tradeoffs associated with NCV removal, published and publicly available food safety and water quality data from the Northeastern United States were obtained. Because data on NCV removal are not widely available, forest-wetland cover was used as a proxy, consistent with previous studies. Structural equation models (SEMs) were used to quantify the effect of forest-wetland cover on (i) food safety outcomes (e.g., detecting pathogens in soil) and (ii) water quality (e.g., nutrient levels). Based on the SEMs, NCV was not associated with or had a protective effect on food safety outcomes (more NCV was associated with a reduced likelihood of pathogen detection). The probabilities of detecting Listeria spp. in soil (effect estimate [EE] = -0.17; P = 0.005) and enterohemorrhagic Escherichia coli in stream samples (EE = -0.27; P < 0.001) were negatively associated with the amount of NCV surrounding the sampling site. Larger amounts of NCV were also associated with lower nutrient, salinity, and sediment levels, and higher dissolved oxygen levels. Total phosphorous levels were negatively associated with the amount of NCV in the upstream watershed (EE = -0.27; P < 0.001). Similar negative associations (P < 0.05) were observed for other physicochemical parameters, such as nitrate (EE = -0.38). Our findings suggest that NCV should not be considered an inherent produce safety risk or result in farm audit demerits. This study also provides a framework for evaluating environmental tradeoffs associated with using specific preharvest food safety strategies. IMPORTANCE Currently, on-farm food safety decisions are typically made independently of conservation considerations, often with detrimental impacts on agroecosystems. Comanaging agricultural environments to simultaneously meet conservation and food safety aims is complicated because farms are closely linked to surrounding environments, and management decisions can have unexpected environmental, economic, and food safety consequences. Thus, there is a need for research on the conservation and food safety tradeoffs associated with implementing specific preharvest food safety practices. Understanding these tradeoffs is critical for developing adaptive comanagement strategies and ensuring the short- and long-term safety, sustainability, and profitability of agricultural systems. This study quantifies tradeoffs and synergies between food safety and environmental aims, and outlines a framework for modeling tradeoffs and synergies between management aims that can be used to support future comanagement research.


Assuntos
Ecossistema , Qualidade da Água , Fazendas , Inocuidade dos Alimentos , Agricultura , Solo
9.
Ren Fail ; 44(1): 581-593, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35357272

RESUMO

BACKGROUND: A subset of patients without overt systemic lupus erythematosus (SLE) present with biopsy findings typically seen in lupus nephritis (LN). Although a minority eventually develops SLE, many do not. It remains unclear how to classify or treat these patients. Our study attempted to further understand the clinical and pathological characteristics of cases with lupus-like nephritis (LLN). METHODS: Among 2700 native kidney biopsies interpreted at University of Rochester Medical Center (URMC) from 2010 to 2019, we identified 27 patients with biopsies showing lupus-like features (LL-fx) and 96 with LN. Of those with LL-fx, 17 were idiopathic LLN and 10 were associated with a secondary etiology (e.g., infection/drugs). RESULTS: At the time of biopsy, the LLN-group tended to be slightly older (44 vs. 35), male (58.8 vs. 17.7%, p = .041), and Caucasian (47.0 vs. 28.1%, p = .005). Chronic kidney disease was the most common biopsy indication in LLN (21.4 vs. 2.8%, p = .001). Both LN and LLN presented with nephrotic-range proteinuria (mean 5.73 vs. 4.40 g/d), and elevated serum creatinine (mean 1.66 vs. 1.47 mg/dL). Tubuloreticular inclusions (TRIs; p < .001) and fibrous crescents (p = .04) were more often seen in LN, while more tubulointerstitial scarring was seen in LLN (p = .011). At mean follow-up of 1684 d (range: 31-4323), none of the LLN patients developed ESRD. A subset of both LN and cases with LL-fx overlapped with other autoimmune diseases. CONCLUSIONS: Lupus-like pathologic features are seen in a wide array of disease processes. The findings suggest that LLN may be a manifestation of an autoimmune process that overlaps with SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Insuficiência Renal Crônica , Biópsia , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/epidemiologia , Nefrite Lúpica/complicações , Masculino , Proteinúria/complicações , Insuficiência Renal Crônica/complicações
10.
Microb Pathog ; 160: 105209, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34563611

RESUMO

People living with HIV have a high incidence of cardiovascular and neurological diseases as comorbid disorders that are commonly linked to inflammation. While microbial translocation can augment inflammation during HIV infection, functional microbiome shifts that may increase pro-inflammatory responses have not been fully characterized. In addition, defining HIV-induced microbiome changes has been complicated by high variability among individuals. Here we conducted functional annotation of previously-published 16S ribosomal RNA gene sequences of 305 HIV positive and 249 negative individuals, with adjustment for geographic region, sex, sexual behavior, and age. Metagenome profiles were inferred from these individuals' 16S data. HIV infection was associated with impaired microbial vitamin B synthesis; around half of the gene families in thiamine and folate biosynthesis pathways were significantly less abundant in the HIV positive group than the negative control. These results are consistent with the high prevalence of thiamine and folate deficiencies in HIV infections. These HIV-induced microbiota shifts have the potential to influence cardiovascular and neurocognitive diseases, given the documented associations between B-vitamin deficiencies, inflammation, and these diseases. We also observed that most essential amino acid biosynthesis pathways were downregulated in the microbiome of HIV-infected individuals. Microbial vitamin B and amino acid synthesis pathways were not significantly recovered by antiretroviral treatment when we compared 262 ART positive and 184 ART negative individuals. Our meta-analysis provides a new outlook for understanding vitamin B and amino acid deficiencies in HIV patients, suggesting that interventions for reversing HIV-induced microbiome shifts may aid in lessening the burdens of HIV comorbidities.


Assuntos
Microbioma Gastrointestinal , Infecções por HIV , Ácido Fólico , Infecções por HIV/complicações , Humanos , Metagenoma , RNA Ribossômico 16S/genética , Tiamina
11.
Matern Child Health J ; 25(12): 1930-1938, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34609706

RESUMO

OBJECTIVE: To determine if cesarean delivery is adversely associated with child neurodevelopment as measured at 20 months and 7 years. METHODS: In a prospective cohort study (n = 1328) in the Republic of Seychelles, we examined the association between mode of delivery and 22 measures of child neurodevelopment spanning multiple domains: cognition, executive and psychomotor function, language development, behavior, scholastic achievement, and social communication. Using multivariable linear regression, we evaluated the relationship between delivery mode (Cesarean/vaginal delivery) and each developmental outcome, while controlling for relevant covariates including child sex and age, maternal age, maternal IQ, whether both parents lived with the child, and Hollingshead socioeconomic status. RESULTS: At 20 months, children born via cesarean delivery had slightly higher scores (ß = 0.11, 95% confidence interval: 0.00, 0.21) on the Infant Behavior Questionnaire-Revised Positive Affectivity/Surgency subtest, a measure of infant temperament, as compared to vaginal delivery. Delivery mode was not associated with any of the 7-year developmental outcomes. CONCLUSIONS FOR PRACTICE: Our study does not support the notion that cesarean delivery is associated with child neurodevelopmental outcomes.


Assuntos
Cesárea , Desenvolvimento Infantil , Criança , Parto Obstétrico , Feminino , Humanos , Lactente , Gravidez , Estudos Prospectivos , Seicheles/epidemiologia
12.
Int J Mol Sci ; 22(22)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34830013

RESUMO

Mercury ranks third on the U.S. Agency of Toxic Substances and Disease Registry priority list of hazardous substances, behind only arsenic and lead. We have undertaken uncovering the mechanisms underlying the developmental toxicity of methylmercury (MeHg), inorganic mercury (HgCl2), lead acetate (Pb), and sodium arsenite (As). To probe these differences, we used the Drosophila model, taking advantage of three developmental transitions-pupariation, metamorphosis, and eclosion-to differentiate potentially unique windows of toxicity. We elaborated dose response profiles for each individual metal administered in food and accounted for internal body burden, also extending analyses to evaluate combinatorial metal mixture effects. We observed all four metals producing larval lethality and delayed pupariation, with MeHg being most potent. Compared to other metals, MeHg's potency is caused by a higher body burden with respect to dose. MeHg uniquely caused dose-dependent failure in eclosion that was unexpectedly rescued by titrating in HgCl2. Our results highlight a unique developmental window and toxicokinetic properties where MeHg acts with specificity relative to HgCl2, Pb, and As. These findings will serve to refine future studies aimed at revealing tissue morphogenesis events and cell signaling pathways, potentially conserved in higher organisms, that selectively mediate MeHg toxicity and its antagonism by HgCl2.


Assuntos
Drosophila melanogaster/efeitos dos fármacos , Mercúrio/toxicidade , Metais/toxicidade , Compostos de Metilmercúrio/toxicidade , Animais , Arsenitos/toxicidade , Drosophila melanogaster/crescimento & desenvolvimento , Humanos , Larva/efeitos dos fármacos , Compostos Organometálicos/toxicidade , Isoformas de Proteínas/toxicidade , Compostos de Sódio/toxicidade , Fenômenos Toxicológicos
13.
BMC Bioinformatics ; 21(1): 545, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33243147

RESUMO

BACKGROUND: Quantitative real-time PCR (qPCR) is one of the most widely used methods to measure gene expression. An important aspect of qPCR data that has been largely ignored is the presence of non-detects: reactions failing to exceed the quantification threshold and therefore lacking a measurement of expression. While most current software replaces these non-detects with a value representing the limit of detection, this introduces substantial bias in the estimation of both absolute and differential expression. Single imputation procedures, while an improvement on previously used methods, underestimate residual variance, which can lead to anti-conservative inference. RESULTS: We propose to treat non-detects as non-random missing data, model the missing data mechanism, and use this model to impute missing values or obtain direct estimates of model parameters. To account for the uncertainty inherent in the imputation, we propose a multiple imputation procedure, which provides a set of plausible values for each non-detect. We assess the proposed methods via simulation studies and demonstrate the applicability of these methods to three experimental data sets. We compare our methods to mean imputation, single imputation, and a penalized EM algorithm incorporating non-random missingness (PEMM). The developed methods are implemented in the R/Bioconductor package nondetects. CONCLUSIONS: The statistical methods introduced here reduce discrepancies in gene expression values derived from qPCR experiments in the presence of non-detects, providing increased confidence in downstream analyses.


Assuntos
Algoritmos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Simulação por Computador , Humanos , Modelos Estatísticos , Tamanho da Amostra
14.
Biometrics ; 76(3): 874-885, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31729013

RESUMO

Bayesian model-based clustering provides a powerful and flexible tool that can be incorporated into regression models to better understand the grouping of observations. Using data from the Seychelles Child Development Study, we explore the effect of prenatal methylmercury exposure on 20 neurodevelopmental outcomes measured in 9-year-old children. Rather than cluster individual subjects, we cluster the outcomes within a multiple outcomes model. By using information in the data to nest the outcomes into groups called domains, the model more accurately reflects the shared characteristics of neurodevelopmental domains and improves estimation of the overall and outcome-specific exposure effects by shrinking effects within and between domains selected by the data. The Bayesian paradigm allows for sampling from the posterior distribution of the grouping parameters; thus, inference can be made about group membership and their defining characteristics. We avoid the often difficult and highly subjective requirement of a priori identification of the total number of groups by incorporating a Dirichlet process prior to form a fully Bayesian multiple outcomes model.


Assuntos
Teorema de Bayes , Criança , Feminino , Humanos , Gravidez
15.
J Asthma ; 57(10): 1053-1062, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31204534

RESUMO

Objective: To examine the prevalence of overweight and obesity in urban adolescents with asthma and to investigate the relationships between anthropometric measures and asthma outcomes including quality of life, asthma control and lung function.Methods: Adolescents with an asthma diagnosis, 12-20 years-old, were recruited from three urban communities in the United States. Spirometry and anthropometric data including height, weight and waist circumferences were collected along with questionnaire data measuring quality of life, asthma control, and medication adherence. Body mass index (BMI) and waist-height ratio (WHtR) were computed.Results: The sample (N = 294) included 48% female and 80% African American. About 50% of the sample were either overweight or obese, and 41% had central obesity. No significant gender interactions with either BMI or WHtR on asthma outcomes were found. Neither BMI nor WHtR predicted quality of life, asthma control or medication adherence, while females had poorer quality of life and asthma control regardless of weight status (p < 0.001). Higher BMI or WHtR predicted higher spirometry values. Regardless of weight status, females had greater percent predicted spirometry values, while raw values (L) were significantly greater in males.Conclusions: High BMI is a common comorbidity among poor, primarily African American, urban adolescents with asthma. The negative impact of being overweight or obese on quality of life or asthma control is yet to be manifested in adolescents. The findings underscore adolescence as an ideal period to safely intervene to reduce excessive body weight, which can prevent the potentially harmful effects of obesity on future asthma outcomes.


Assuntos
Asma/epidemiologia , Asma/fisiopatologia , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , População Urbana/estatística & dados numéricos , Adolescente , Fatores Etários , Asma/etnologia , Índice de Massa Corporal , Pesos e Medidas Corporais , Criança , Feminino , Humanos , Masculino , Sobrepeso/etnologia , Obesidade Infantil/etnologia , Qualidade de Vida , Fatores Sexuais , Espirometria , Estados Unidos/epidemiologia , Adulto Jovem
16.
Environ Res ; 183: 109072, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32007747

RESUMO

BACKGROUND: Exposure to the environmental toxicant mercury (Hg) has been associated with immune dysregulation, including autoimmune disease, but few human studies have examined methylmercury (MeHg) exposure from fish consumption. OBJECTIVES: We examined associations between MeHg exposure and biological markers of autoimmunity and inflammation while adjusting for long chain polyunsaturated fatty acids (LCPUFA). METHOD: At age 19 years, hair total Hg (Y19Hg), LCPUFA status, a panel of 13 antinuclear antibodies (ANA), total serum immunoglobulins (Ig) IgG, IgA, and IgM and serum markers of inflammation (IL-1, IL-2, IL-6, IL-10, C-reactive protein (CRP), IFN-γ, TNF-α) were measured in the Seychelles Child Development Study (SCDS) Main Cohort (n = 497). Multivariable regression models investigated the association between Y19Hg and biomarkers, adjusting for prenatal total hair Hg (MatHg) and other relevant covariates, and with and without adjustment for LCPUFA. RESULTS: With each 1 ppm increase in Y19Hg (mean 10.23 (SD 6.02) ppm) we observed a 4% increased odds in a positive Combined ANA following adjustment for the n6:n3 LCPUFA ratio (ß = 0.036, 95%; CI: 0.001, 0.073). IgM was negatively associated with Y19Hg (ß = -0.016, 95%CI: 0.016, -0.002) in models adjusted for n-3, n-6 LCPUFA and when separately adjusted for the n-6:n-3 LCPUFA ratio. No associations were observed with MatHg. Total n-3 LCPUFA status was associated with reduced odds of a positive anti-ribonuclear protein (RNP) A. The n-3 LCPUFA were negatively associated with IL-6, IL-10, CRP, IFN-γ, TNF-α and positively with TNF-α:IL-10. There were positive associations between the n-6:n-3 ratio and IL-6, IL-10, CRP, IFN-γ, TNF-α and a negative association with TNF-α:IL-10. DISCUSSION: The Y19Hg exposure was associated with higher ANA and lower IgM albeit only following adjustment for the n-3 LCPUFA or the n-6:n-3 LCPUFA ratio. The clinical significance of these findings is unclear, but warrant follow up at an older age to determine any relationship to the onset of autoimmune disease.


Assuntos
Doenças Autoimunes , Ácidos Graxos Ômega-3 , Compostos de Metilmercúrio , Animais , Doenças Autoimunes/etiologia , Criança , Dieta , Ácidos Graxos Insaturados , Feminino , Humanos , Masculino , Compostos de Metilmercúrio/toxicidade , Gravidez , Seicheles , Adulto Jovem
18.
Bioinformatics ; 34(12): 2046-2052, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29438560

RESUMO

Motivation: Around 2.1 million new HIV-1 infections were reported in 2015, alerting that the HIV-1 epidemic remains a significant global health challenge. Precise incidence assessment strengthens epidemic monitoring efforts and guides strategy optimization for prevention programs. Estimating the onset time of HIV-1 infection can facilitate optimal clinical management and identify key populations largely responsible for epidemic spread and thereby infer HIV-1 transmission chains. Our goal is to develop a genomic assay estimating the incidence and infection time in a single cross-sectional survey setting. Results: We created a web-based platform, HIV-1 incidence and infection time estimator (HIITE), which processes envelope gene sequences using hierarchical clustering algorithms and informs the stage of infection, along with time since infection for incident cases. HIITE's performance was evaluated using 585 incident and 305 chronic specimens' envelope gene sequences collected from global cohorts including HIV-1 vaccine trial participants. HIITE precisely identified chronically infected individuals as being chronic with an error less than 1% and correctly classified 94% of recently infected individuals as being incident. Using a mixed-effect model, an incident specimen's time since infection was estimated from its single lineage diversity, showing 14% prediction error for time since infection. HIITE is the first algorithm to inform two key metrics from a single time point sequence sample. HIITE has the capacity for assessing not only population-level epidemic spread but also individual-level transmission events from a single survey, advancing HIV prevention and intervention programs. Availability and implementation: Web-based HIITE and source code of HIITE are available at http://www.hayounlee.org/software.html. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Biologia Computacional/métodos , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , HIV-1/genética , Software , Algoritmos , Estudos Transversais , Feminino , Infecções por HIV/prevenção & controle , Humanos , Incidência , Masculino , Modelos Biológicos , Polimorfismo Genético , Análise de Sequência de RNA/métodos
20.
Ann Allergy Asthma Immunol ; 122(1): 58-64, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30213611

RESUMO

BACKGROUND: Adequate assessment of control is critical to asthma management. The Asthma Control Questionnaire (ACQ) and the National Asthma Education and Prevention Program (NAEPP) criteria are commonly used measures of asthma control. OBJECTIVE: To examine the associations between the ACQ and NAEPP criteria and compare the validity in association with lung function, asthma exacerbation, and quality of life. METHODS: The ACQ and the NAEPP criteria were administered to 373 adolescents with asthma aged 12 to 20 years. The 2 measures correlated with forced expiratory volume in 1 second (FEV1), asthma exacerbation (oral corticosteroid use, hospitalization, and emergency department [ED] use) in the past 12 months, and quality of life. RESULTS: Agreement between the ACQ and NAEPP criteria was moderate (κ = 0.40-0.61). Neither of the 2 measures was a reliable predictor of FEV1 less than 80% because of the high rate of false-positive results for the ACQ (68%) and low sensitivity for the NAEPP (49%). The NAEPP identified more cases of uncontrolled asthma (84.6%) than the ACQ (64.6%). The ACQ was a significant predictor of recent oral corticosteroid use, hospitalization, and ED visits (area under the curve = 0.66, 0.66, and 0.64, respectively; P < .001), as was NAEPP (area under the curve = 0.63, 0.66, and 0.61, respectively; P < .001). Both measures were significantly associated with quality of life, and the associations were particularly strong for the ACQ (r = -0.87 for symptom subscale, r = -0.76 for activity subscale, and r = -0.78 for emotional function subscale). CONCLUSION: Neither the ACQ nor the NAEPP appears to reliably predict lung function, whereas both measures reasonably associate with acute asthma exacerbation. The ACQ may be the superior measure in gauging the psychosocial effect of asthma control given its particularly strong associations with quality of life. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02293499.


Assuntos
Asma/terapia , Inquéritos Epidemiológicos/estatística & dados numéricos , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida/psicologia , Adolescente , Adulto , Humanos , Adulto Jovem
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