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1.
J Couns Psychol ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115904

RESUMO

In this study we assessed the construct validity of the recently published White Racial Affect Scale (Grzanka et al., 2020). Specifically, we assessed the convergent, criterion-related, and incremental evidence for construct validity of the White guilt, White shame, and White defensiveness (called "White negation" in the original article) factors. We used a video stimulus to trigger state guilt and shame in participants as part of the construct validity investigation. White adults in the United States signed up for the study online (N = 262) and watched a 5-min video stimulus and completed questionnaires before and after the video. Results of this study replicated many of the findings from the original White Racial Affect Scale validation study (Grzanka et al., 2020). We found strong evidence of construct validity for the White guilt and White defensiveness factors and mixed evidence for the White shame factor. We discuss directions for future research and implications for potential interventions. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

2.
BMC Res Notes ; 17(1): 214, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090704

RESUMO

OBJECTIVE: We attempted to conduct a randomized controlled trial of three different informed consent training formats to evaluate their effectiveness. We recruited 503 clinical research professionals, who received $50 for participation. Incidental findings showed unexpectedly low rates of compliance with completing the study training protocols, resulting in insufficient statistical power to test our original hypotheses. In this report, we conducted a secondary analysis of the data in which we characterize and evaluate the observed low compliance. This involved using literature on average reading times, speed-reading times, and video play speeds to calculate the timeframes required to complete the three training formats. RESULTS: Only 13% of participants completed the training in a reasonable timeframe. Furthermore, only 46% of participants completed the training in the minimum possible timeframe. These findings lead us to ask whether online research training is effective, since no training can be effective if participants do not actually complete the training. Given extensive requirements for educational training among clinical research professionals, we feel the burden of proof is on training programs to demonstrate that they have positive effects.


Assuntos
Pesquisadores , Humanos , Pesquisadores/educação , Pesquisadores/estatística & dados numéricos , Consentimento Livre e Esclarecido , Pesquisa Biomédica/educação , Feminino , Masculino , Fidelidade a Diretrizes/estatística & dados numéricos , Adulto
3.
J Clin Transl Sci ; 7(1): e28, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36721403

RESUMO

Introduction: Several evidence-informed consent practices (ECPs) have been shown to improve informed consent in clinical trials but are not routinely used. These include optimizing consent formatting, using plain language, using validated instruments to assess understanding, and involving legally authorized representatives when appropriate. We hypothesized that participants receiving an implementation science toolkit and a social media push would have increased adoption of ECPs and other outcomes. Methods: We conducted a 1-year trial with clinical research professionals in the USA (n = 1284) who have trials open to older adults or focus on Alzheimer's disease. We randomized participants to receive information on ECPs via receiving a toolkit with a social media push (intervention) or receiving an online learning module (active control). Participants completed a baseline survey and a follow-up survey after 1 year. A subset of participants was interviewed (n = 43). Results: Participants who engaged more with the toolkit were more likely to have tried to implement an ECP during the trial than participants less engaged with the toolkit or the active control group. However, there were no significant differences in the adoption of ECPs, intention to adopt, or positive attitudes. Participants reported the toolkit and social media push were satisfactory, and participating increased their awareness of ECPs. However, they reported lacking the time needed to engage with the toolkit more fully. Conclusions: Using an implementation science approach to increase the use of ECPs was only modestly successful. Data suggest that having institutional review boards recommend or require ECPs may be an effective way to increase their use.

4.
Forensic Sci Int Genet ; 58: 102663, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35168910

RESUMO

The production and trade of objects manufactured from the skeletal axis of coralid precious corals is a historically, culturally and economically important global industry. Coralids are members of the diverse Coralliidae family, which contains several species complexes and morphospecies. For most precious coral found in the jewelry trade, the color remains the sole clue and link to the taxonomic identity of the individual. Different coralid species have however similar or overlapping colors resulting in difficulty to taxonomically identify jewelry objects, including four species listed by the Convention on the International Trade of Endangered Species (CITES) whose international transport and trade requires species-specific and country of origin documentation. We aimed at developing a reliable method to taxonomically identify coralid material with the objective of distinguishing CITES protected species from their non-protected counterparts. We present Coral-ID, a genetic assay to taxonomically classify coralid objects using quasi non-destructive sampling. The assay classifies the analyzed sample in one of six taxonomic categories and performs at least presumptive separation of CITES-listed and non-listed species in all cases. Developmental validation experiments prove that Coral-ID is a specific, accurate and very sensitive method. As the first attempt to randomly sample corals in the trade to identify them, we applied Coral-ID on 20 precious coral objects seized by custom authorities upon import to in Switzerland. Thirteen (65%) of these samples could be analyzed; three of these were found to be presumptively CITES-listed, and 10 of them have proven to originate from non-CITES-listed species.


Assuntos
Antozoários , Animais , Antozoários/genética , Comércio , Testes Genéticos , Humanos , Internacionalidade , Especificidade da Espécie
5.
J Empir Res Hum Res Ethics ; 17(1-2): 177-192, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34410175

RESUMO

Recent revisions to the Common Rule require that consent documents begin with a focused presentation of the study's key information that is organized to facilitate understanding. We surveyed 1,284 researchers working with older adults or individuals with Alzheimer's disease, supplemented with 60 qualitative interviews, to understand current use and barriers to using evidence-based formatting and plain language in key information. Researchers reported using formatting in 42% of their key information sections, and plain language in 63% of their key information sections. Perceived barriers included lack of knowledge, Institutional Review Board, other members of their team, and the burden associated with implementation. Education and training are required to increase adoption of the practices.


Assuntos
Ensaios Clínicos como Assunto/métodos , Consentimento Livre e Esclarecido , Idioma , Idoso , Termos de Consentimento , Comitês de Ética em Pesquisa , Humanos , Pesquisadores
6.
PLoS One ; 16(12): e0261719, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34972126

RESUMO

Qualitative health data are rarely shared in the United States (U.S.). This is unfortunate because gathering qualitative data is labor and time-intensive, and data sharing enables secondary research, training, and transparency. A new U.S. federal policy mandates data sharing by 2023, and is agnostic to data type. We surveyed U.S. qualitative researchers (N = 425) on the barriers and facilitators of sharing qualitative health or sensitive research data. Most researchers (96%) have never shared qualitative data in a repository. Primary concerns were lack of participant permission to share data, data sensitivity, and breaching trust. Researcher willingness to share would increase if participants agreed and if sharing increased the societal impact of their research. Key resources to increase willingness to share were funding, guidance, and de-identification assistance. Public health and biomedical researchers were most willing to share. Qualitative researchers need to prepare for this new reality as sharing qualitative data requires unique considerations.


Assuntos
Acesso à Informação , Disseminação de Informação , Pesquisa Qualitativa , Pesquisadores , Adulto , Pesquisa Biomédica , Confiabilidade dos Dados , Coleta de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , National Institutes of Health (U.S.) , Saúde Pública , Inquéritos e Questionários , Confiança , Estados Unidos
7.
J Clin Transl Sci ; 5(1): e164, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34589234

RESUMO

INTRODUCTION: Participants and research professionals often overestimate how well participants understand and appreciate consent information for clinical trials, and experts often vary in their determinations of participant's capacity to consent to research. Past research has developed and validated instruments designed to assess participant understanding and appreciation, but the frequency with which they are utilized is unknown. METHODS: We administered a survey to clinical researchers working with older adults or those at risk of cognitive impairment (N = 1284), supplemented by qualitative interviews (N = 60). RESULTS: We found that using a validated assessment of consent is relatively uncommon, being used by only 44% of researchers who had an opportunity. Factors that predicted adoption of validated assessments included not seeing the study sponsor as a barrier, positive attitudes toward assessments, and being confident that they had the resources needed to implement an assessment. The perceived barriers to adopting validated assessments of consent included lack of awareness, lack of knowledge, being unsure of how to administer such an assessment, and the burden associated with implementing this practice. CONCLUSIONS: Increasing the use of validated assessments of consent will require educating researchers on the practice and emphasizing very practical assessments, and may require Institutional Review Boards (IRBs) or study sponsors to champion the use of assessments.

9.
J Clin Transl Sci ; 5(1): e120, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34267947

RESUMO

PURPOSE: This paper reports on a novel measure, attitudes toward genomics and precision medicine (AGPM), which evaluates attitudes toward activities such as genetic testing, collecting information on lifestyle, and genome editing - activities necessary to achieve the goals of precision medicine. DISCUSSION: The AGPM will be useful for researchers who want to explore attitudes toward genomics and precision medicine. The association of concerns about precision medicine activities with demographic variables such as religion and politics, as well as higher levels of education, suggests that further education on genomic and precision activities alone is unlikely to shift AGPM scores significantly. METHODS: We wrote items to represent psychological and health benefits of precision medicine activities, and concerns about privacy, social justice, harm to embryos, and interfering with nature. We validated the measure through factor analysis of its structure, and testing associations with trust in the health information system and demographic variables such as age, sex, education, and religion. RESULTS: The AGPM had excellent alpha reliability (.92) and demonstrated good convergent validity with existing measures. Variables most strongly associated with higher levels of concern with precision medicine activities included: regular religious practice, republican political leanings, and higher levels of education.

10.
Health Promot Pract ; 21(1): 91-96, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30103623

RESUMO

A 2009 community needs assessment highlighted the health care gap facing Hispanic residents in Hampton, Virginia, one of the major cities served by Eastern Virginia Medical School (EVMS). Survey respondents indicated the following as health care barriers: language, lack of knowledge, and lack of a community health center. EVMS students worked to bridge the health care gap between existing needs and services by establishing and maintaining the Clínica Comunitaria Esperanza, a culturally and linguistically competent student-run free clinic serving uninsured Hispanics in the Hampton Roads area. This article provides a model for engaging effectively with a priority population through partnerships that facilitate understanding of the community concerns, values, culture, and existing local resources that serve as determinants of health. This article further illustrates how the integration of two preexisting EVMS programs, the HOPES (Health Outreach Partnership of EVMS Students) Clinic and the Medical Spanish program, has supported the development and sustainability of Clínica Comunitaria Esperanza. The HOPES Clinic is a student-run free clinic that provides both general and specialty care to uninsured patients. EVMS' Medical Spanish program is a longitudinal service learning initiative composed of medical students, faculty, and staff dedicated to providing inclusive health care to meet the needs of the local Spanish-speaking community.


Assuntos
Competência Cultural , Promoção da Saúde/organização & administração , Hispânico ou Latino/educação , Clínica Dirigida por Estudantes/organização & administração , Estudantes de Medicina , Relações Comunidade-Instituição , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoas sem Cobertura de Seguro de Saúde , Universidades/organização & administração , Virginia
11.
J Nutr Biochem ; 41: 34-41, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28038359

RESUMO

NFκB-mediated inflammation contributes to liver injury during nonalcoholic steatohepatitis (NASH). We hypothesized that antiinflammatory activities of green tea extract (GTE) during NASH would lower tumor necrosis factor receptor-1 (TNFR1)- and Toll-like receptor-4 (TLR4)-mediated NFκB activation. Male C57BL6/J mice (6 weeks old) were fed a low-fat (LF) or high-fat (HF) diet for 12 weeks to induce NASH. They were then randomized to continue on these diets supplemented with 0 or 2% GTE (n=10/group) for an additional 8 weeks prior to evaluating NASH, NFκB inflammation and TNFR1 and TLR4 receptor complexes and their respective ligands, TNFα and endotoxin. HF feeding increased (P<.05) serum alanine aminotransferase (ALT) activity and histological evidence of NASH compared with LF controls. HF-mediated increases in NFκB p65 phosphorylation were also accompanied by increased serum TNFα and endotoxin concentrations, mRNA expression of hepatic TNFR1 and TLR4 and MyD88 protein levels. GTE in LF mice had no effect (P>.05) on liver histology or inflammatory responses. However, GTE in HF mice decreased biochemical and histological parameters of NASH and lowered hepatic p65 phosphorylation in association with decreased serum TNFα, mRNA expression of TNFR1 and TLR4 and MyD88 protein. GTE in HF-fed mice also lowered serum endotoxin and up-regulated mRNA expression of duodenal occludin and zonula occluden-1 and ileal occludin and claudin-1 that were otherwise lowered in expression by HF feeding. These data suggest that dietary GTE treatment reduces hepatic inflammation in NASH by decreasing proinflammatory signaling through TNFR1 and TLR4 that otherwise increases NFκB activation and liver injury.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Camellia sinensis/química , Suplementos Nutricionais , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Extratos Vegetais/uso terapêutico , Receptores Tipo I de Fatores de Necrose Tumoral/antagonistas & inibidores , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Anti-Inflamatórios não Esteroides/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Manipulação de Alimentos , Regulação da Expressão Gênica , Ligantes , Fígado/imunologia , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/imunologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Oxirredução , Fosforilação , Extratos Vegetais/efeitos adversos , Folhas de Planta/química , Processamento de Proteína Pós-Traducional , Distribuição Aleatória , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/metabolismo
12.
PLoS One ; 11(10): e0165279, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27798660

RESUMO

Deep-sea corals are a critical component of habitat in the deep-sea, existing as regional hotspots for biodiversity, and are associated with increased assemblages of fish, including commercially important species. Because sampling these species is so difficult, little is known about the connectivity and life history of deep-sea octocoral populations. This study evaluates the genetic connectivity among 23 individuals of the deep-sea octocoral Swiftia simplex collected from Eastern Pacific waters along the west coast of the United States. We utilized high-throughput restriction-site associated DNA (RAD)-tag sequencing to develop the first molecular genetic resource for the deep-sea octocoral, Swiftia simplex. Using this technique we discovered thousands of putative genome-wide SNPs in this species, and after quality control, successfully genotyped 1,145 SNPs across individuals sampled from California to Washington. These SNPs were used to assess putative population structure across the region. A STRUCTURE analysis as well as a principal coordinates analysis both failed to detect any population differentiation across all geographic areas in these collections. Additionally, after assigning individuals to putative population groups geographically, no significant FST values could be detected (FST for the full data set 0.0056), and no significant isolation by distance could be detected (p = 0.999). Taken together, these results indicate a high degree of connectivity and potential panmixia in S. simplex along this portion of the continental shelf.


Assuntos
Antozoários/genética , Fluxo Gênico , Técnicas de Genotipagem , Análise de Sequência de DNA , Animais , Sequência de Bases , Genética Populacional , Geografia , Heterozigoto , Metadados , Oceanos e Mares , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Análise de Componente Principal , Reprodutibilidade dos Testes , Mapeamento por Restrição , Tamanho da Amostra , Especificidade da Espécie , Estados Unidos
14.
J Hered ; 107(2): 122-33, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26712859

RESUMO

Understanding the genetic architecture of phenotypic traits can provide important information about the mechanisms and genomic regions involved in local adaptation and speciation. Here, we used genotyping-by-sequencing and a combination of previously published and newly generated data to construct sex-specific linkage maps for sockeye salmon (Oncorhynchus nerka). We then used the denser female linkage map to conduct quantitative trait locus (QTL) analysis for 4 phenotypic traits in 3 families. The female linkage map consisted of 6322 loci distributed across 29 linkage groups and was 4082 cM long, and the male map contained 2179 loci found on 28 linkage groups and was 2291 cM long. We found 26 QTL: 6 for thermotolerance, 5 for length, 9 for weight, and 6 for condition factor. QTL were distributed nonrandomly across the genome and were often found in hotspots containing multiple QTL for a variety of phenotypic traits. These hotspots may represent adaptively important regions and are excellent candidates for future research. Comparing our results with studies in other salmonids revealed several regions with overlapping QTL for the same phenotypic trait, indicating these regions may be adaptively important across multiple species. Altogether, our study demonstrates the utility of genomic data for investigating the genetic basis of important phenotypic traits. Additionally, the linkage map created here will enable future research on the genetic basis of phenotypic traits in salmon.


Assuntos
Mapeamento Cromossômico , Locos de Características Quantitativas , Salmão/genética , Análise de Sequência de DNA , Animais , Feminino , Ligação Genética , Genótipo , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único
15.
Mol Nutr Food Res ; 60(4): 858-70, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26679056

RESUMO

SCOPE: Green tea extract (GTE) reduces liver steatosis and inflammation during nonalcoholic steatohepatitis (NASH). We hypothesized GTE would mitigate NASH in a nuclear factor erythroid-2-related-factor-2 (Nrf2)-dependent manner in a high fat (HF) induced model. METHODS AND RESULTS: Nrf2-null and wild-type (WT) mice were fed an HF diet containing 0 or 2% GTE for eight weeks prior to assessing parameters of NASH. Compared to WT mice, Nrf2-null mice had increased serum alanine aminotransferase, hepatic triglyceride, expression of free fatty acid uptake and lipogenic genes, malondialdehyde and NFκB phosphorylation and expression of pro-inflammatory genes. In WT mice, GTE increased Nrf2 and NADPH:quinone oxidoreductase-1 mRNA, and lowered hepatic steatosis, lipid uptake and lipogenic gene expression, malondialdehyde, and NFκB-dependent inflammation. In Nrf2-null mice, GTE lowered NFκB phosphorylation and TNF-α and MCP1 mRNA to levels observed in WT mice fed GTE whereas hepatic triglyceride and lipogenic genes were lowered only to those of WT mice fed no GTE. Malondialdehyde was lowered in Nrf2-null mice fed GTE, but not to levels of WT mice, and without improving the hepatic antioxidants α-tocopherol, ascorbic acid and uric acid. CONCLUSION: Nrf2 deficiency exacerbates NASH whereas anti-inflammatory and hypolipidemic activities of GTE likely occur largely independent of Nrf2 signaling.


Assuntos
Camellia sinensis/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Dieta Hiperlipídica/efeitos adversos , Humanos , Inflamação/dietoterapia , Inflamação/metabolismo , Metabolismo dos Lipídeos/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Hepatopatia Gordurosa não Alcoólica/etiologia , Substâncias Protetoras/farmacologia
16.
Appl Environ Microbiol ; 81(7): 2395-407, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25616798

RESUMO

Small- and medium-size farms in the mid-Atlantic region of the United States use varied agricultural practices to produce leafy greens during spring and fall, but the impact of preharvest practices on food safety risk remains unclear. To assess farm-level risk factors, bacterial indicators, Salmonella enterica, and Shiga toxin-producing Escherichia coli (STEC) from 32 organic and conventional farms were analyzed. A total of 577 leafy greens, irrigation water, compost, field soil, and pond sediment samples were collected. Salmonella was recovered from 2.2% of leafy greens (n = 369) and 7.7% of sediment (n = 13) samples. There was an association between Salmonella recovery and growing season (fall versus spring) (P = 0.006) but not farming system (organic or conventional) (P = 0.920) or region (P = 0.991). No STEC was isolated. In all, 10% of samples were positive for E. coli: 6% of leafy greens, 18% of irrigation water, 10% of soil, 38% of sediment, and 27% of compost samples. Farming system was not a significant factor for levels of E. coli or aerobic mesophiles on leafy greens but was a significant factor for total coliforms (TC) (P < 0.001), with higher counts from organic farm samples. Growing season was a factor for aerobic mesophiles on leafy greens (P = 0.004), with higher levels in fall than in spring. Water source was a factor for all indicator bacteria (P < 0.001), and end-of-line groundwater had marginally higher TC counts than source samples (P = 0.059). Overall, the data suggest that seasonal events, weather conditions, and proximity of compost piles might be important factors contributing to microbial contamination on farms growing leafy greens.


Assuntos
Agricultura/métodos , Inocuidade dos Alimentos , Salmonella enterica/isolamento & purificação , Escherichia coli Shiga Toxigênica/isolamento & purificação , Verduras/microbiologia , Carga Bacteriana , Enterobacteriaceae/isolamento & purificação , Mid-Atlantic Region , Medição de Risco , Estações do Ano
17.
Int J Food Microbiol ; 196: 98-108, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25540859

RESUMO

In the mid-Atlantic region of the United States, small- and medium-sized farmers use varied farm management methods and water sources to produce tomatoes. It is unclear whether these practices affect the food safety risk for tomatoes. This study was conducted to determine the prevalence, and assess risk factors for Salmonella enterica, Shiga toxin-producing Escherichia coli (STEC) and bacterial indicators in pre-harvest tomatoes and their production areas. A total of 24 organic and conventional, small- to medium-sized farms were sampled for six weeks in Maryland (MD), Delaware (DE) and New Jersey (NJ) between July and September 2012, and analyzed for indicator bacteria, Salmonella and STEC. A total of 422 samples--tomato fruit, irrigation water, compost, field soil and pond sediment samples--were collected, 259 of which were tomato samples. A low level of Salmonella-specific invA and Shiga toxin genes (stx1 or stx2) were detected, but no Salmonella or STEC isolates were recovered. Of the 422 samples analyzed, 9.5% were positive for generic E. coli, found in 5.4% (n=259) of tomato fruits, 22.5% (n=102) of irrigation water, 8.9% (n=45) of soil, 3/9 of pond sediment and 0/7 of compost samples. For tomato fruit, farming system (organic versus conventional) was not a significant factor for levels of indicator bacteria. However, the total number of organic tomato samples positive for generic E. coli (1.6%; 2/129) was significantly lower than for conventional tomatoes (6.9% (9/130); (χ(2) (1)=4.60, p=0.032)). Region was a significant factor for levels of Total Coliforms (TC) (p=0.046), although differences were marginal, with western MD having the highest TC counts (2.6 log CFU/g) and NJ having the lowest (2.0 log CFU/g). Tomatoes touching the ground or plastic mulch harbored significantly higher levels of TC compared to vine tomatoes, signaling a potential risk factor. Source of irrigation water was a significant factor for all indicator bacteria (p<0.0001), and groundwater had lower bacterial levels than surface water. End of line surface water samples were not significantly different from source water samples, but end of line groundwater samples had significantly higher bacterial counts than source (p<0.0001), suggesting that Good Agricultural Practices that focus on irrigation line maintenance might be beneficial. In general, local effects other than cropping practices, including topography, land use and adjacent industries, might be important factors contributing to microbiological inputs on small- and medium-sized farms in the mid-Atlantic region.


Assuntos
Agricultura , Fenômenos Fisiológicos Bacterianos , Inocuidade dos Alimentos , Frutas/microbiologia , Microbiologia do Solo , Solanum lycopersicum/microbiologia , Bactérias/isolamento & purificação , Escherichia coli/isolamento & purificação , Escherichia coli/fisiologia , Água Doce/microbiologia , Mid-Atlantic Region , Fatores de Risco , Salmonella enterica/isolamento & purificação , Salmonella enterica/fisiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Escherichia coli Shiga Toxigênica/fisiologia
18.
Mol Ecol ; 24(1): 151-79, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25442828

RESUMO

We compared whole transcriptome variation in six pre-adult stages and seven adult female ages in two populations of cactophilic Drosophila mojavensis reared on two host plants to understand how differences in gene expression influence standing life history variation. We used singular value decomposition (SVD) to identify dominant trajectories of life cycle gene expression variation, performed pairwise comparisons of stage and age differences in gene expression across the life cycle, identified when genes exhibited maximum levels of life cycle gene expression, and assessed population and host cactus effects on gene expression. Life cycle SVD analysis returned four significant components of transcriptional variation, revealing functional enrichment of genes responsible for growth, metabolic function, sensory perception, neural function, translation and ageing. Host cactus effects on female gene expression revealed population- and stage-specific differences, including significant host plant effects on larval metabolism and development, as well as adult neurotransmitter binding and courtship behaviour gene expression levels. In 3- to 6-day-old virgin females, significant upregulation of genes associated with meiosis and oogenesis was accompanied by downregulation of genes associated with somatic maintenance, evidence for a life history trade-off. The transcriptome of D. mojavensis reared in natural environments throughout its life cycle revealed core developmental transitions and genome-wide influences on life history variation in natural populations.


Assuntos
Drosophila/genética , Meio Ambiente , Estágios do Ciclo de Vida/genética , Transcriptoma , Animais , Cactaceae , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Larva/genética , México , Dados de Sequência Molecular , Análise de Sequência de DNA
19.
Conserv Biol ; 29(3): 755-64, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25494697

RESUMO

We examined how ecological and evolutionary (eco-evo) processes in population dynamics could be better integrated into population viability analysis (PVA). Complementary advances in computation and population genomics can be combined into an eco-evo PVA to offer powerful new approaches to understand the influence of evolutionary processes on population persistence. We developed the mechanistic basis of an eco-evo PVA using individual-based models with individual-level genotype tracking and dynamic genotype-phenotype mapping to model emergent population-level effects, such as local adaptation and genetic rescue. We then outline how genomics can allow or improve parameter estimation for PVA models by providing genotypic information at large numbers of loci for neutral and functional genome regions. As climate change and other threatening processes increase in rate and scale, eco-evo PVAs will become essential research tools to evaluate the effects of adaptive potential, evolutionary rescue, and locally adapted traits on persistence.


Assuntos
Conservação dos Recursos Naturais/métodos , Modelos Genéticos , Animais , Evolução Biológica , Mudança Climática , Ecologia , Genótipo , Invertebrados/genética , Fenótipo , Plantas/genética , Dinâmica Populacional , Vertebrados/genética
20.
Evolution ; 68(12): 3357-67, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25178652

RESUMO

The existence of complex (multiple-step) genetic adaptations that are "irreducible" (i.e., all partial combinations are less fit than the original genotype) is one of the longest standing problems in evolutionary biology. In standard genetics parlance, these adaptations require the crossing of a wide adaptive valley of deleterious intermediate stages. Here, we demonstrate, using a simple model, that evolution can cross wide valleys to produce "irreducibly complex" adaptations by making use of previously cryptic mutations. When revealed by an evolutionary capacitor, previously cryptic mutants have higher initial frequencies than do new mutations, bringing them closer to a valley-crossing saddle in allele frequency space. Moreover, simple combinatorics implies an enormous number of candidate combinations exist within available cryptic genetic variation. We model the dynamics of crossing of a wide adaptive valley after a capacitance event using both numerical simulations and analytical approximations. Although individual valley crossing events become less likely as valleys widen, by taking the combinatorics of genotype space into account, we see that revealing cryptic variation can cause the frequent evolution of complex adaptations.


Assuntos
Adaptação Fisiológica/genética , Evolução Molecular , Variação Genética , Modelos Genéticos , Animais , Feminino , Hibridização Genética , Masculino
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