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1.
Crit Rev Toxicol ; 51(6): 467-508, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34569909

RESUMO

We utilized a practical, transparent approach for systematically reviewing a chemical-specific evidence base. This approach was used for a case study of ozone inhalation exposure and adverse metabolic effects (overweight/obesity, Type 1 diabetes [T1D], Type 2 diabetes [T2D], and metabolic syndrome). We followed the basic principles of systematic review. Studies were defined as "Suitable" or "Supplemental." The evidence for Suitable studies was characterized as strong or weak. An overall causality judgment for each outcome was then determined as either causal, suggestive, insufficient, or not likely. Fifteen epidemiologic and 33 toxicologic studies were Suitable for evidence synthesis. The strength of the human evidence was weak for all outcomes. The toxicologic evidence was weak for all outcomes except two: body weight, and impaired glucose tolerance/homeostasis and fasting/baseline hyperglycemia. The combined epidemiologic and toxicologic evidence was categorized as weak for overweight/obesity, T1D, and metabolic syndrome,. The association between ozone exposure and T2D was determined to be insufficient or suggestive. The streamlined approach described in this paper is transparent and focuses on key elements. As systematic review guidelines are becoming increasingly complex, it is worth exploring the extent to which related health outcomes should be combined or kept distinct, and the merits of focusing on critical elements to select studies suitable for causal inference. We recommend that systematic review results be used to target discussions around specific research needs for advancing causal determinations.


Assuntos
Diabetes Mellitus Tipo 2 , Ozônio , Humanos , Obesidade/induzido quimicamente , Ozônio/toxicidade
2.
Environ Res ; 173: 318-329, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30951958

RESUMO

INTRODUCTION: The use of biomonitoring data as an indicator of national levels of human exposure to environmental chemicals has grown in importance and prevalence. Nationally representative urinary bisphenol A (BPA) data are now available for Canada, the United States and Korea. Here we address the following questions: Are urinary BPA data from these countries comparable? What can be discerned regarding geographic and/or temporal similarities or differences? Are there generalizable lessons to be learned regarding comparison of biomonitoring results from different countries? METHODS: We examined underlying methods and resultant urinary BPA data from national surveys of three countries: Canada (Canadian Health Measures Survey, CHMS, 2009-2015); United States (National Health and Nutrition Examination Survey, NHANES, 2009-2014); and Korea (Korean National Environmental Health Survey, KoNEHS, 2009-2014). We estimated BPA daily intakes on both a volume- and creatinine-adjusted basis. RESULTS: The three countries use similar methods for analyzing urine samples for BPA and participate in external proficiency testing with acceptable results. Field blanks are only used in the CHMS program. There were program-specific differences in fasting times of participants. Median urinary BPA levels in Canada remained relatively constant over the three cycles (1.1-1.2 ng/ml), while US levels decreased (from 1.9 to 1.3 ng/ml) and Korean levels increased (from 0.7 to 1.1 ng/ml) over similar time periods. The most recent survey year data indicate that levels do not differ substantially across countries. Canadian urinary BPA levels have been stable; the subtle, non-significant decrease in intakes may be due to higher body weight in the more recent Canadian surveys. In contrast, the decrease in intakes in the US appears to be due to decreases in urinary BPA as body weights in the US have been stable. Estimated 95th percentile intakes are over an order of magnitude below current health-based guidance values. DISCUSSION: Our assessment of urinary BPA data from Canada, the US and Korea indicates that methodological differences, methods for dilution adjustment, and population characteristics should be carefully considered when interpreting biomonitoring data. Despite the plethora of publications describing issues with use of creatinine levels for urinary dilution adjustment, there have been no major methodological advances that would assist in interpreting urinary chemical data. A combination of biomonitoring and traditional exposure assessment approaches may be needed to fully assess human exposures to BPA and other chemicals. CONCLUSIONS: National biomonitoring surveys provide important information on population levels of chemicals such as BPA and can assist in understanding temporal and geographic similarities, differences, and trends. However, caution must be exercised when using these data to draw anything but broad conclusions, due to both intercountry methodological differences and factors affecting urinary chemical levels that are still poorly understood. While the issues raised in this paper do not appear to be a major concern specifically for the national-scale monitoring of BPA described here, they must be considered when comparing data for other chemicals measured as part of both national and smaller-scale biomonitoring-based research as well as for BPA data from other studies.


Assuntos
Compostos Benzidrílicos , Exposição Ambiental , Poluentes Ambientais , Inquéritos Nutricionais , Fenóis , Monitoramento Biológico , Canadá , Monitoramento Ambiental , Humanos , República da Coreia , Estados Unidos
3.
Environ Res ; 171: 302-312, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30708234

RESUMO

Recent rapid technological advances are producing exposure data sets for which there are no available data quality assessment tools. At the same time, regulatory agencies are moving in the direction of data quality assessment for environmental risk assessment and decision-making. A transparent and systematic approach to evaluating exposure data will aid in those efforts. Any approach to assessing data quality must consider the level of quality needed for the ultimate use of the data. While various fields have developed approaches to assess data quality, there is as yet no general, user-friendly approach to assess both measured and modeled data in the context of a fit-for-purpose risk assessment. Here we describe ExpoQual, an instrument developed for this purpose which applies recognized parameters and exposure data quality elements from existing approaches for assessing exposure data quality. Broad data streams such as quantitative measured and modeled human exposure data as well as newer and developing approaches can be evaluated. The key strength of ExpoQual is that it facilitates a structured, reproducible and transparent approach to exposure data quality evaluation and provides for an explicit fit-for-purpose determination. ExpoQual was designed to minimize subjectivity and to include transparency in aspects based on professional judgment. ExpoQual is freely available on-line for testing and user feedback (exposurequality.com).


Assuntos
Exposição Ambiental , Tomada de Decisões , Humanos , Medição de Risco
4.
Am Heart J ; 197: 18-26, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29447780

RESUMO

BACKGROUND: The CPORT-E trial showed the noninferiority of nonprimary percutaneous coronary intervention (PCI) at hospitals without cardiac surgery on-site (SoS) compared with hospitals with SoS for 6-week mortality and 9-month major adverse cardiac events (MACE). However, target vessel revascularization (TVR) was increased at non-SoS hospitals. Therefore, we aimed to determine the consistency of the CPORT-E trial findings across the spectrum of enrolled patients. METHODS: Post hoc subgroup analyses of 6-week mortality and 9-month MACE, defined as the composite of death, Q-wave myocardial infarction, or TVR, were performed. Patients with and without 9-month TVR and rates of related outcomes were compared. RESULTS: There was no interaction between SoS status and clinically relevant subgroups for 6-week mortality or 9-month MACE (P for any interaction=.421 and .062, respectively). In addition to increased 9-month rates of TVR and diagnostic catheterization at hospitals without SoS, non-TVR was also increased (2.7% vs 1.9%, P=.002); there was no difference in myocardial infarction-driven TVR, non-TVR, or diagnostic catheterization. Predictors of 9-month TVR included intra-aortic balloon pump use, any index PCI complication, and 3-vessel PCI, whereas predictors of freedom from TVR included SoS, discharge on a P2Y12 inhibitor, and stent implantation. CONCLUSIONS: The noninferiority of nonprimary PCI at non-SoS hospitals was consistent across clinically relevant subgroups. Elective PCI at an SoS hospital conferred a TVR benefit which may be related to a lower rate of referral for diagnostic catheterization for reasons other than myocardial infarction.


Assuntos
Cateterismo Cardíaco , Procedimentos Cirúrgicos Cardíacos , Doença da Artéria Coronariana , Vasos Coronários , Hospitais , Infarto do Miocárdio , Revascularização Miocárdica , Idoso , Cateterismo Cardíaco/métodos , Cateterismo Cardíaco/estatística & dados numéricos , Procedimentos Cirúrgicos Cardíacos/métodos , Procedimentos Cirúrgicos Cardíacos/estatística & dados numéricos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Procedimentos Cirúrgicos Eletivos/métodos , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Feminino , Hospitais/classificação , Hospitais/normas , Hospitais/estatística & dados numéricos , Humanos , Balão Intra-Aórtico/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Mortalidade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/terapia , Revascularização Miocárdica/efeitos adversos , Revascularização Miocárdica/métodos , Revascularização Miocárdica/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde , Índice de Gravidade de Doença
5.
Crit Rev Toxicol ; 48(1): 1-51, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28741979

RESUMO

The ability of epidemiologic evidence to inform regulatory decisions is largely dependent on the coherence and quality of the published literature. This systematic review examines the quality and consistency of studies assessing health outcomes associated with exposure to triclosan (TCS), an antimicrobial chemical with a short physiologic half-life. We used elements of the Biomonitoring, Environmental Epidemiology, and Short-Lived Chemicals instrument to evaluate aspects of study quality. Each methodological domain - overall design, exposure assessment, and data analysis - was categorized according to three tiers where Tier 1 indicated the highest quality. We also examined consistency of methods, results and reporting as considerations for weight of evidence (WOE) assessment. Studies were considered sufficiently comparable if they addressed the same or similar research questions. Forty-two studies met the criteria for inclusion. Only one randomized cross-over clinical trial of TCS was assigned to Tier 1 for all three domains. Most other studies were assigned to Tier 3 for at least one domain. Although the available literature examined more than 100 different health endpoints and reported hundreds of different measures of association, few studies were considered comparable. For reported measures of association, most were not significantly different from the null; the few statistically significant results represented isolated findings without a discernable across- or within-study pattern. We conclude that the current body of epidemiologic literature does not allow a meaningful WOE assessment due to methodological limitations of individual studies and lack of inter-study consistency. On the other hand, methodologically stronger studies may be used to inform future research.


Assuntos
Anti-Infecciosos/toxicidade , Triclosan/toxicidade , Anti-Infecciosos/farmacologia , Feminino , Humanos , Masculino , Triclosan/farmacologia
6.
Wound Repair Regen ; 26(2): 213-220, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29683538

RESUMO

In a multicenter randomized controlled trial (RCT), the use of viable cryopreserved placental membrane (vCPM) for chronic diabetic foot ulcers (DFUs) resulted in a higher proportion of wound closure in comparison to good wound care: 62% versus 21% (p < 0.01). However, patients in RCTs are not representative of daily physician practice. Healthcare databases serve as a valuable tool to evaluate therapy effectiveness and to supplement evidence from RCTs. The objective of this study was to evaluate the effectiveness of vCPM for DFU management using Net Health's WoundExpert® electronic health records (EHR). The primary endpoint was the proportion of DFUs that achieved complete closure. Other endpoints included time and number of grafts to closure, probability of wound closure by week 12, and the number of wound-related infections and amputations. De-identified EHR data for 360 patients with 441 wounds treated with vCPM were extracted from the database. Average patient age was 63.7 years with a mean wound size of 5.1 cm2 and an average wound duration of 102 days prior to vCPM treatment. For evaluation of clinical outcomes, 350 DFUs larger than 0.25 cm2 at baseline were analyzed. Closure at the end of treatment was achieved in 59.4% of wounds with a median treatment duration of 42.0 days and 4 applications of vCPM. The probability of wound closure at week 12 was 71%, and the number of amputations and wound-related infections was 13 (3.0%) and 9 (2.0%), respectively. Data also demonstrated a correlation between wound size and closure rate as well as a correlation between > 50% wound area reduction by week 4 and wound closure by week 12. The results of this study mirror previous RCT efficacy data, supporting the benefits of vCPM for DFU management. These results can also influence policy and treatment decisions regarding advanced vCPM technology.


Assuntos
Criopreservação , Pé Diabético/terapia , Placenta/transplante , Cicatrização/fisiologia , Amputação Cirúrgica/estatística & dados numéricos , Pé Diabético/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tratamento de Ferimentos com Pressão Negativa , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Resultado do Tratamento
7.
Catheter Cardiovasc Interv ; 90(3): 366-377, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28160375

RESUMO

OBJECTIVES: To compare bivalirudin to heparin during non-primary percutaneous coronary intervention (PCI). BACKGROUND: The optimal anticoagulant to support PCI remains uncertain. METHODS: We performed a propensity score-based analysis comparing clinical outcomes of patients receiving heparin to those receiving bivalirudin during non-primary PCI. RESULTS: Of 18,867 patients in the Cardiovascular Patient Outcomes Research Team Non-Primary PCI (CPORT-E) trial, we selected 7,913 patients undergoing non-staged PCI of whom 57.3% received heparin and 42.7% received bivalirudin. In-hospital myocardial infarction occurred in 4.4% of patients receiving bivalirudin and 3.0% of patients receiving heparin (relative risk [RR] 1.5, 95% confidence interval [CI] 1.1-2.1, P = 0.022); this difference persisted at 6 weeks (5.0% vs. 3.6%, RR 1.4, 95% CI 1.0-1.8, P = 0.041). There was no difference in all-cause mortality either in-hospital (0.2% vs. 0.1% for heparin vs. bivalirudin, P = 0.887) or at 6 weeks (0.5% vs. 0.7%, P = 0.567). In-hospital bleeding requiring transfusion occurred in 0.9% of patients receiving bivalirudin and 1.9% of patients receiving heparin (RR 0.4, 95% CI 0.3-0.7, P <0.001), but there was no difference at 6 weeks (2.7% for heparin vs. 1.9% for bivalirudin, RR 0.7, 95% CI 0.5-1.0, P = 0.062). CONCLUSIONS: In patients undergoing non-primary PCI at hospitals without on-site cardiac surgery, bivalirudin was associated with a decreased risk of in-hospital bleeding requiring transfusion and an increased risk of in-hospital MI compared to heparin. © 2017 Wiley Periodicals, Inc.


Assuntos
Anticoagulantes/uso terapêutico , Antitrombinas/uso terapêutico , Doença das Coronárias/terapia , Heparina/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Intervenção Coronária Percutânea , Idoso , Anticoagulantes/efeitos adversos , Antitrombinas/efeitos adversos , Transfusão de Sangue , Doença das Coronárias/sangue , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/mortalidade , Feminino , Hemorragia/induzido quimicamente , Hemorragia/terapia , Heparina/efeitos adversos , Hirudinas/efeitos adversos , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Razão de Chances , Fragmentos de Peptídeos/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Pontuação de Propensão , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
8.
Artigo em Inglês | MEDLINE | ID: mdl-29157177

RESUMO

The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) has been commercially available since the 1940's. Despite decades of data on 2,4-D in food, air, soil, and water, as well as in humans, the quality the quality of these data has not been comprehensively evaluated. Using selected elements of the Biomonitoring, Environmental Epidemiology, and Short-lived Chemicals (BEES-C) instrument (temporal variability, avoidance of sample contamination, analyte stability, and urinary methods of matrix adjustment), the quality of 156 publications of environmental- and biomonitoring-based 2,4-D data was examined. Few publications documented steps were taken to avoid sample contamination. Similarly, most studies did not demonstrate the stability of the analyte from sample collection to analysis. Less than half of the biomonitoring publications reported both creatinine-adjusted and unadjusted urine concentrations. The scope and detail of data needed to assess temporal variability and sources of 2,4-D varied widely across the reviewed studies. Exposures to short-lived chemicals such as 2,4-D are impacted by numerous and changing external factors including application practices and formulations. At a minimum, greater transparency in reporting of quality control measures is needed. Perhaps the greatest challenge for the exposure community is the ability to reach consensus on how to address problems specific to short-lived chemical exposures in observational epidemiology investigations. More extensive conversations are needed to advance our understanding of human exposures and enable interpretation of these data to catch up to analytical capabilities. The problems defined in this review remain exquisitely difficult to address for chemicals like 2,4-D, with short and variable environmental and physiological half-lives and with exposures impacted by numerous and changing external factors.


Assuntos
Ácido 2,4-Diclorofenoxiacético/análise , Biomarcadores/análise , Exposição Ambiental/análise , Poluentes Ambientais/análise , Monitoramento Ambiental/métodos , Humanos , Saúde Pública , Medição de Risco
9.
PLoS Comput Biol ; 11(10): e1004416, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26436540

RESUMO

Recent improvements in next-generation sequencing of tumor samples and the ability to identify somatic mutations at low allelic fractions have opened the way for new approaches to model the evolution of individual cancers. The power and utility of these models is increased when tumor samples from multiple sites are sequenced. Temporal ordering of the samples may provide insight into the etiology of both primary and metastatic lesions and rationalizations for tumor recurrence and therapeutic failures. Additional insights may be provided by temporal ordering of evolving subclones--cellular subpopulations with unique mutational profiles. Current methods for subclone hierarchy inference tightly couple the problem of temporal ordering with that of estimating the fraction of cancer cells harboring each mutation. We present a new framework that includes a rigorous statistical hypothesis test and a collection of tools that make it possible to decouple these problems, which we believe will enable substantial progress in the field of subclone hierarchy inference. The methods presented here can be flexibly combined with methods developed by others addressing either of these problems. We provide tools to interpret hypothesis test results, which inform phylogenetic tree construction, and we introduce the first genetic algorithm designed for this purpose. The utility of our framework is systematically demonstrated in simulations. For most tested combinations of tumor purity, sequencing coverage, and tree complexity, good power (≥ 0.8) can be achieved and Type 1 error is well controlled when at least three tumor samples are available from a patient. Using data from three published multi-region tumor sequencing studies of (murine) small cell lung cancer, acute myeloid leukemia, and chronic lymphocytic leukemia, in which the authors reconstructed subclonal phylogenetic trees by manual expert curation, we show how different configurations of our tools can identify either a single tree in agreement with the authors, or a small set of trees, which include the authors' preferred tree. Our results have implications for improved modeling of tumor evolution and the importance of multi-region tumor sequencing.


Assuntos
Evolução Clonal/genética , Análise Mutacional de DNA/métodos , DNA de Neoplasias/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mutação/genética , Neoplasias/genética , Algoritmos , Animais , Sequência de Bases , Evolução Molecular , Camundongos , Dados de Sequência Molecular , Reconhecimento Automatizado de Padrão/métodos , Análise de Célula Única/métodos
10.
Stat Appl Genet Mol Biol ; 13(4): 477-96, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24918456

RESUMO

As the complexity and heterogeneity of cancer is being increasingly appreciated through genomic analyses, microarray-based cancer classification comprising multiple discriminatory molecular markers is an emerging trend. Such multiclass classification problems pose new methodological and computational challenges for developing novel and effective statistical approaches. In this paper, we introduce a new approach for classifying multiple disease states associated with cancer based on gene expression profiles. Our method focuses on detecting small sets of genes in which the relative comparison of their expression values leads to class discrimination. For an m-class problem, the classification rule typically depends on a small number of m-gene sets, which provide transparent decision boundaries and allow for potential biological interpretations. We first test our approach on seven common gene expression datasets and compare it with popular classification methods including support vector machines and random forests. We then consider an extremely large cohort of leukemia cancer patients to further assess its effectiveness. In both experiments, our method yields comparable or even better results to benchmark classifiers. In addition, we demonstrate that our approach can integrate pathway analysis of gene expression to provide accurate and biological meaningful classification.


Assuntos
Perfilação da Expressão Gênica/métodos , Expressão Gênica , Leucemia/classificação , Leucemia/genética , Modelos Genéticos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Transcriptoma , Biomarcadores Tumorais/genética , Humanos , Máquina de Vetores de Suporte
11.
Environ Res ; 142: 84-95, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26121292

RESUMO

Nationally representative data on urinary levels of BPA and its metabolites in the United States from the 2003-2004 to 2011-2012 National Health and Nutrition Examination Surveys (NHANES) were used to estimate daily BPA intakes and examine temporal trends. Additionally, NHANES data on lifestyle/demographic/dietary factors previously reported to be associated with BPA exposures were examined to assess the resiliency of the reported associations (whether the association is maintained across the five surveys). Finally, various approaches for addressing issues with the use of BPA concentration data from spot urine samples were examined for their effect on trends and associations. Three approaches were assessed here: (i) use of generic literature-based 24-h urine excretion volumes, (ii) use of creatinine adjustments, and (iii) use of individual urine flow rate data from NHANES. Based on 2011-2012 NHANES urinary BPA data and assumptions described in this paper, the median daily intake for the overall population is approximately 25 ng/kg day; median intake estimates were approximately two to three orders of magnitude below current health-based guidance values. Estimates of daily BPA intake have decreased significantly compared to those from the 2003-2004 NHANES. Estimates of associations between lifestyle/demographic/dietary factors and BPA exposure revealed inconsistencies related to both NHANES survey year and the three approaches listed above; these results demonstrate the difficulties in interpreting urinary BPA data, despite efforts to account for urine dilution and translation of spot sample data to 24-h data. The results further underscore the importance of continued research on how to best utilize urinary measures of environmental chemicals in exposure research. Until a consensus is achieved regarding the best biomonitoring approaches for assessing exposures to short-lived chemicals using urine samples, research on factors associated with BPA exposures should include - and report results from - assessments using both volume-based urinary BPA and creatinine-adjusted urinary BPA data.


Assuntos
Compostos Benzidrílicos/urina , Exposição Ambiental/análise , Poluentes Ambientais/urina , Fenóis/urina , Urina/química , Adolescente , Adulto , Idoso , Compostos Benzidrílicos/efeitos adversos , Criança , Interpretação Estatística de Dados , Dieta , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/efeitos adversos , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Fenóis/efeitos adversos , Manejo de Espécimes , Estados Unidos , Adulto Jovem
12.
Proc Natl Acad Sci U S A ; 109(28): 11116-20, 2012 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-22733748

RESUMO

It has been difficult to determine how cognitive systems change over the grand time scale of an entire life, as few cognitive systems are well enough understood; observable in infants, adolescents, and adults; and simple enough to measure to empower comparisons across vastly different ages. Here we address this challenge with data from more than 10,000 participants ranging from 11 to 85 years of age and investigate the precision of basic numerical intuitions and their relation to students' performance in school mathematics across the lifespan. We all share a foundational number sense that has been observed in adults, infants, and nonhuman animals, and that, in humans, is generated by neurons in the intraparietal sulcus. Individual differences in the precision of this evolutionarily ancient number sense may impact school mathematics performance in children; however, we know little of its role beyond childhood. Here we find that population trends suggest that the precision of one's number sense improves throughout the school-age years, peaking quite late at ∼30 y. Despite this gradual developmental improvement, we find very large individual differences in number sense precision among people of the same age, and these differences relate to school mathematical performance throughout adolescence and the adult years. The large individual differences and prolonged development of number sense, paired with its consistent and specific link to mathematics ability across the age span, hold promise for the impact of educational interventions that target the number sense.


Assuntos
Cognição , Matemática , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Humanos , Individualidade , Internet , Pessoa de Meia-Idade , Neurônios/fisiologia , Reprodutibilidade dos Testes , Software
13.
J Child Psychol Psychiatry ; 55(4): 374-83, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24256459

RESUMO

BACKGROUND: Unstuck and On Target (UOT) is an executive function (EF) intervention for children with autism spectrum disorders (ASD) targeting insistence on sameness, flexibility, goal-setting, and planning through a cognitive-behavioral program of self-regulatory scripts, guided/faded practice, and visual/verbal cueing. UOT is contextually-based because it is implemented in school and at home, the contexts in which a child uses EF skills. METHODS: To evaluate the effectiveness of UOT compared with a social skills intervention (SS), 3rd-5th graders with ASD (mean IQ = 108; UOT n = 47; SS n = 20) received interventions delivered by school staff in small group sessions. Students were matched for gender, age, race, IQ, ASD symptomotolgy, medication status, and parents' education. Interventions were matched for 'dose' of intervention and training. Measures of pre-post change included classroom observations, parent/teacher report, and direct child measures of problem-solving, EF, and social skills. Schools were randomized and evaluators, but not parents or teachers, were blinded to intervention type. RESULTS: Interventions were administered with high fidelity. Children in both groups improved with intervention, but mean change scores from pre- to postintervention indicated significantly greater improvements for UOT than SS groups in: problem-solving, flexibility, and planning/organizing. Also, classroom observations revealed that participants in UOT made greater improvements than SS participants in their ability to follow rules, make transitions, and be flexible. Children in both groups made equivalent improvements in social skills. CONCLUSIONS: These data support the effectiveness of the first contextually-based EF intervention for children with ASD. UOT improved classroom behavior, flexibility, and problem-solving in children with ASD. Individuals with variable background/training in ASD successfully implemented UOT in mainstream educational settings.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/terapia , Terapia Cognitivo-Comportamental/métodos , Função Executiva , Criança , Transtornos Globais do Desenvolvimento Infantil/psicologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Resolução de Problemas , Instituições Acadêmicas , Habilidades Sociais , Resultado do Tratamento , Escalas de Wechsler
14.
Environ Sci Technol ; 47(9): 4787-95, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23582134

RESUMO

Women in the United States have breast milk concentrations of polybrominated diphenyl ethers (PBDEs) that are among the highest in the world, leading to concerns over the potential health implications to breastfeeding infants during critical stages of growth and development. Developing cost-effective and sustainable methods for assessing chemical exposures in infants is a high priority to federal agencies and local communities. PBDE data are available in nationally representative serum samples but not in breast milk. As a method to predict PBDE concentrations in U.S. breast milk, we present the development of congener-specific linear regression partitioning models and their application to U.S. serum data. Models were developed from existing paired milk and serum data and applied to 2003-2004 NHANES serum data for U.S. women. Highest estimated median U.S. breast milk concentrations were for BDE-47 (30.6 ng/g lipid) and BDE-99 (6.1 ng/g lipid) with the median concentration of Σ7PBDEs estimated at 54.2 ng/g lipid. Predictions of breast milk PBDE concentration were consistent with reported concentrations from 11 similarly timed U.S. studies. When applied to NHANES data, these models provide a sustainable method for estimating population-level concentrations of PBDEs in U.S. breast milk and should improve exposure estimates in breastfeeding infants.


Assuntos
Exposição Ambiental , Éteres Difenil Halogenados/análise , Leite Humano/química , Adulto , Feminino , Éteres Difenil Halogenados/sangue , Humanos , Lactente , Recém-Nascido , Modelos Teóricos , Fatores de Risco , Estados Unidos
15.
Nat Genet ; 32(1): 166-74, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12185365

RESUMO

Retroviral insertional mutagenesis in BXH2 and AKXD mice induces a high incidence of myeloid leukemia and B- and T-cell lymphoma, respectively. The retroviral integration sites (RISs) in these tumors thus provide powerful genetic tags for the discovery of genes involved in cancer. Here we report the first large-scale use of retroviral tagging for cancer gene discovery in the post-genome era. Using high throughput inverse PCR, we cloned and analyzed the sequences of 884 RISs from a tumor panel composed primarily of B-cell lymphomas. We then compared these sequences, and another 415 RIS sequences previously cloned from BXH2 myeloid leukemias and from a few AKXD lymphomas, against the recently assembled mouse genome sequence. These studies identified 152 loci that are targets of retroviral integration in more than one tumor (common retroviral integration sites, CISs) and therefore likely to encode a cancer gene. Thirty-six CISs encode genes that are known or predicted to be genes involved in human cancer or their homologs, whereas others encode candidate genes that have not yet been examined for a role in human cancer. Our studies demonstrate the power of retroviral tagging for cancer gene discovery in the post-genome era and indicate a largely unrecognized complexity in mouse and presumably human cancer.


Assuntos
Leucemia Mieloide/genética , Linfoma de Células B/genética , Retroviridae/genética , Integração Viral/genética , Animais , Genes Supressores de Tumor , Humanos , Camundongos , Camundongos Endogâmicos , Oncogenes , Reação em Cadeia da Polimerase , Provírus/genética
16.
bioRxiv ; 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37383947

RESUMO

Accurate identification of cell classes across the tissues of living organisms is central in the analysis of growing atlases of single-cell RNA sequencing (scRNA-seq) data across biomedicine. Such analyses are often based on the existence of highly discriminating "marker genes" for specific cell classes which enables a deeper functional understanding of these classes as well as their identification in new, related datasets. Currently, marker genes are defined by methods that serially assess the level of differential expression (DE) of individual genes across landscapes of diverse cells. This serial approach has been extremely useful, but is limited because it ignores possible redundancy or complementarity across genes, that can only be captured by analyzing several genes at the same time. We wish to identify discriminating panels of genes. To efficiently explore the vast space of possible marker panels, leverage the large number of cells often sequenced, and overcome zero-inflation in scRNA-seq data, we propose viewing panel selection as a variation of the "minimal set-covering problem" in combinatorial optimization which can be solved with integer programming. In this formulation, the covering elements are genes, and the objects to be covered are cells of a particular class, where a cell is covered by a gene if that gene is expressed in that cell. Our method, CellCover, identifies a panel of marker genes in scRNA-seq data that covers one class of cells within a population. We apply this method to generate covering marker gene panels which characterize cells of the developing mouse neocortex as postmitotic neurons are generated from neural progenitor cells (NPCs). We show that CellCover captures cell class-specific signals distinct from those defined by DE methods and that CellCover's compact gene panels can be expanded to explore cell type specific function.Transfer learning experiments exploring these covering panels across in vivo mouse, primate, and human scRNA-seq datasets demonstrate that CellCover identifies markers of conserved cell classes in neurogenesis, as well as markers of temporal progression in the molecular identity of these cell types across development of the mammalian neocortex. The gene covering panels we identify across cell types and developmental time can be freely explored in visualizations across all the public data we use in this report at with NeMo Analytics [1] through https://nemoanalytics.org/p?l=CellCover . The code for CellCover is written in R and the Gurobi R interface and is available at [2].

17.
J Biol Chem ; 286(12): 10744-54, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21252230

RESUMO

The bakers' yeast Saccharomyces cerevisiae utilizes a high affinity Ca(2+) influx system (HACS) to survive assaults by mating pheromones, tunicamycin, and azole-class antifungal agents. HACS consists of two known subunits, Cch1 and Mid1, that are homologous and analogous to the catalytic α-subunits and regulatory α2δ-subunits of mammalian voltage-gated calcium channels, respectively. To search for additional subunits and regulators of HACS, a collection of gene knock-out mutants was screened for abnormal uptake of Ca(2+) after exposure to mating pheromone or to tunicamycin. The screen revealed that Ecm7 is required for HACS function in most conditions. Cycloheximide chase experiments showed that Ecm7 was stabilized by Mid1, and Mid1 was stabilized by Cch1 in non-signaling conditions, suggesting they all interact. Ecm7 is a member of the PMP-22/EMP/MP20/Claudin superfamily of transmembrane proteins that includes γ-subunits of voltage-gated calcium channels. Eleven additional members of this superfamily were identified in yeast, but none was required for HACS activity in response to the stimuli. Remarkably, many dozens of genes involved in vesicle-mediated trafficking and protein secretion were required to prevent spontaneous activation of HACS. Taken together, the findings suggest that HACS and calcineurin monitor performance of the membrane trafficking system in yeasts and coordinate compensatory processes. Conservation of this quality control system in Candida glabrata suggests that many pathogenic species of fungi may utilize HACS and calcineurin to resist azoles and other compounds that target membrane biosynthesis.


Assuntos
Canais de Cálcio/metabolismo , Cálcio/metabolismo , Membrana Celular/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Azóis/farmacologia , Canais de Cálcio/genética , Candida/genética , Candida/metabolismo , Membrana Celular/genética , Farmacorresistência Fúngica/efeitos dos fármacos , Farmacorresistência Fúngica/fisiologia , Estudo de Associação Genômica Ampla/métodos , Transporte de Íons/efeitos dos fármacos , Transporte de Íons/fisiologia , Glicoproteínas de Membrana/genética , Estabilidade Proteica/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
18.
Circ Cardiovasc Interv ; 15(2): e011308, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35067071

RESUMO

BACKGROUND: Greater insight into sex-based differences in health status can lay the foundation for more equitable health care. This study compares differences in health status of women and men in the CPORT-E trial (Cardiovascular Patient Outcomes Research Team Non-Primary Percutaneous Coronary Intervention) undergoing nonprimary percutaneous coronary intervention. METHODS: We compared Seattle Angina Questionnaire scores at baseline, 6 weeks, and 9 months for 6851 women and 12 016 men undergoing nonprimary percutaneous coronary intervention. RESULTS: Proportions of angina-free patients increased from 26.2% and 29.8% at baseline to 71.6% and 78.7% at 6 weeks to 78.1% and 83.0% at 9 months in women and men, respectively (P<0.001 for all). After adjusting for clinical and procedural characteristics as well as baseline angina, freedom from angina in women was 34% less likely at 6 weeks (odds ratio, 0.66 [95% CI, 0.61-0.71]; P<0.001) and 32% less likely at 9 months (odds ratio, 0.68 [95% CI, 0.62-0.74]; P<0.001) compared with men. CONCLUSIONS: Although health status increased significantly after percutaneous coronary intervention in both women and men, women had poorer health status outcomes than men before and after percutaneous coronary intervention. Additional investigation into therapies that address the causes of poorer health status in women with coronary artery disease is needed. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00549796.


Assuntos
Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Angina Pectoris/diagnóstico , Angina Pectoris/terapia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Feminino , Nível de Saúde , Humanos , Masculino , Intervenção Coronária Percutânea/efeitos adversos , Fatores de Risco , Caracteres Sexuais , Resultado do Tratamento
19.
Environ Health Perspect ; 130(2): 25002, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35195447

RESUMO

BACKGROUND: Despite 20 y of biomonitoring studies of per- and polyfluoroalkyl substances (PFAS) in both serum and urine, we have an extremely limited understanding of PFAS concentrations in breast milk of women from the United States and Canada. The lack of robust information on PFAS concentrations in breast milk and implications for breastfed infants and their families were brought to the forefront by communities impacted by PFAS contamination. OBJECTIVES: The objectives of this work are to: a) document published PFAS breast milk concentrations in the United States and Canada; b) estimate breast milk PFAS levels from maternal serum concentrations in national surveys and communities impacted by PFAS; and c) compare measured/estimated milk PFAS concentrations to screening values. METHODS: We used three studies reporting breast milk concentrations in the United States and Canada We also estimated breast milk PFAS concentrations by multiplying publicly available serum concentrations by milk:serum partitioning ratios for perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), and perfluorononanoic acid (PFNA). Measured and estimated breast milk concentrations were compared to children's drinking water screening values. DISCUSSION: Geometric means of estimated breast milk concentrations ranged over approximately two orders of magnitude for the different surveys/communities. All geometric mean and mean estimated and measured breast milk PFOA and PFOS concentrations exceeded drinking water screening values for children, sometimes by more than two orders of magnitude. For PFHxS and PFNA, all measured breast milk levels were below the drinking water screening values for children; the geometric mean estimated breast milk concentrations were close to-or exceeded-the children's drinking water screening values for certain communities. Exceeding a children's drinking water screening value does not indicate that adverse health effects will occur and should not be interpreted as a reason to not breastfeed; it indicates that the situation should be further evaluated. It is past time to have a better understanding of environmental chemical transfer to-and concentrations in-an exceptional source of infant nutrition. https://doi.org/10.1289/EHP10359.


Assuntos
Ácidos Alcanossulfônicos , Água Potável , Poluentes Ambientais , Fluorocarbonos , Aleitamento Materno , Canadá , Caprilatos , Criança , Água Potável/análise , Feminino , Humanos , Lactente , Leite Humano/química , Estados Unidos
20.
Mol Cell Proteomics ; 8(1): 19-31, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18755735

RESUMO

Plants appear to have two types of active defenses, a broad-spectrum basal system and a system controlled by R-genes providing stronger resistance to some pathogens that break the basal defense. However, it is unknown if the systems are separate entities. Therefore, we analyzed proteins from leaves of the dry bean crop plant Phaseolus vulgaris using a high-throughput liquid chromatography tandem mass spectrometry method. By statistically comparing the amounts of proteins detected in a single plant variety that is susceptible or resistant to infection, depending on the strains of a rust fungus introduced, we defined basal and R-gene-mediated plant defenses at the proteomic level. The data reveal that some basal defense proteins are potential regulators of a strong defense weakened by the fungus and that the R-gene modulates proteins similar to those in the basal system. The results satisfy a new model whereby R-genes are part of the basal system and repair disabled defenses to reinstate strong resistance.


Assuntos
Basidiomycota/fisiologia , Basidiomycota/patogenicidade , Phaseolus/microbiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/análise , Proteoma/análise , Proteômica , Regulação da Expressão Gênica de Plantas , Imunidade Inata , Modelos Biológicos , Phaseolus/genética , Phaseolus/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , Proteínas de Plantas/genética , Virulência
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