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1.
Prev Sci ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517605

RESUMO

The onset of the COVID-19 pandemic and associated long-term shifts to virtual instruction among most US schools presented notable challenges among education researchers. Ongoing projects conducted in school settings experienced sudden losses of access to teacher and student participants, in many cases leading to severe interruptions to data collection efforts. Perhaps most notably, upon returns to in-person instruction in the 2021/22 academic year most schools instigated strict policies limiting the number of non-school personnel who could enter school buildings, including researchers conducting in-person data collections. As such, many researchers had to find alternative means to gather data. In this paper, we offer a new protocol that we created in response to these challenges that allows for the secure and fully remote collection of video data in school settings. This new protocol not only addressed the immediate needs of the focal study but also addresses some of the most notable barriers to collecting classroom video data in the field of education research at large. In this paper, we describe the initial development and application of this protocol among a local study of elementary teachers, as well as the scaling of this protocol in a study of elementary teachers in multiple states. It is our hope that this protocol can expand education researchers', practitioners', and policymakers' access to classroom video data.

2.
J Biol Chem ; 298(11): 102505, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36126773

RESUMO

MutS homologs (MSHs) are highly conserved core components of DNA mismatch repair. Mismatch recognition provokes ATP-binding by MSH proteins that drives a conformational transition from a short-lived lesion-searching clamp to an extremely stable sliding clamp on the DNA. Here, we have expanded on previous bulk biochemical studies to examine the stability, lifetime, and kinetics of bacterial and human MSH sliding clamps on mismatched DNA using surface plasmon resonance and single-molecule analysis of fluorescently labeled proteins. We found that ATP-bound MSH complexes bound to blocked-end or very long mismatched DNAs were extremely stable over a range of ionic conditions. These observations underpinned the development of a high-throughput Förster resonance energy transfer system that specifically detects the formation of MSH sliding clamps on mismatched DNA. The Förster resonance energy transfer system is capable of distinguishing between HsMSH2-HsMSH3 and HsMSH2-HsMSH6 and appears suitable for chemical inhibitor screens. Taken together, our results provide additional insight into MSH sliding clamps as well as methods to distinguish their functions in mismatch repair.


Assuntos
Proteínas de Escherichia coli , Proteína MutS de Ligação de DNA com Erro de Pareamento , Humanos , Trifosfato de Adenosina/metabolismo , Pareamento Incorreto de Bases , DNA/metabolismo , Reparo de Erro de Pareamento de DNA , Proteínas de Escherichia coli/metabolismo , Proteína MutS de Ligação de DNA com Erro de Pareamento/genética , Proteína MutS de Ligação de DNA com Erro de Pareamento/metabolismo , Proteína 2 Homóloga a MutS/genética , Proteína 2 Homóloga a MutS/metabolismo , Proteínas MutS/genética , Ligação Proteica
3.
BMC Public Health ; 23(1): 429, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36879214

RESUMO

BACKGROUND: Indigenous youth worldwide continue to experience disproportional rates of poorer mental health and well-being compared to non-Indigenous youth. Mentoring has been known to establish favorable outcomes in many areas of health but is still in its early phases of research within Indigenous contexts. This paper explores the barriers and facilitators of Indigenous youth mentoring programs to improve mental health outcomes and provides evidence for governments' response to the United Nations Declaration on the Rights of Indigenous Peoples. METHODS: A systematic search for published studies was conducted on PubMed, Embase, Scopus, CINAHL, and grey literature through Trove, OpenGrey, Indigenous HealthInfoNet, and Informit Indigenous Collection. All papers included in the search were peer-reviewed and published from 2007 to 2021. The Joanna Briggs Institute approaches to critical appraisal, data extraction, data synthesis, and confidence of findings were used. RESULTS: A total of eight papers describing six mentoring programs were included in this review; six papers were from Canada, and two originated from Australia. Studies included mentor perspectives (n = 4) (incorporating views of parents, carers, Aboriginal assistant teachers, Indigenous program facilitators, young adult health leaders, and community Elders), mentee perspectives (n = 1), and both mentor and mentee perspectives (n = 3). Programs were conducted nationally (n = 3) or within specific local Indigenous communities (n = 3) with varying mentor styles and program focus. Five synthesized findings were identified from the data extraction process, each consisting of four categories. These synthesized findings were: establishing cultural relevancy, facilitating environments, building relationships, facilitating community engagement, and leadership responsibilities, which were discussed in the context of extant mentoring theoretical frameworks. CONCLUSION: Mentoring is an appropriate strategy for improving general well-being. However, more research is needed to explore program sustainability and maintaining outcomes in the long term.


Assuntos
Tutoria , Adulto Jovem , Adolescente , Humanos , Idoso , Mentores , Academias e Institutos , Austrália , Canadá
4.
J Biol Chem ; 296: 100550, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33744295

RESUMO

Retroviral integrases must navigate host DNA packaged as chromatin during integration of the viral genome. Prototype foamy virus (PFV) integrase (IN) forms a tetramer bound to two viral DNA (vDNA) ends in a complex termed an intasome. PFV IN consists of four domains: the amino terminal extension domain (NED), amino terminal domain (NTD), catalytic core domain (CCD), and carboxyl terminal domain (CTD). The domains of the two inner IN protomers have been visualized, as well as the CCDs of the two outer IN protomers. However, the roles of the amino and carboxyl terminal domains of the PFV intasome outer subunits during integration to a nucleosome target substrate are not clear. We used the well-characterized 601 nucleosome to assay integration activity as well as intasome binding. PFV intasome integration to 601 nucleosomes occurs in clusters at four independent sites. We find that the outer protomer NED and NTD domains have no significant effects on integration efficiency, site selection, or binding. The CTDs of the outer PFV intasome subunits dramatically affect nucleosome binding but have little effect on total integration efficiency. The outer PFV IN CTDs did significantly alter the integration efficiency at one site. Histone tails also significantly affect intasome binding, but have little impact on PFV integration efficiency or site selection. These results indicate that binding to nucleosomes does not correlate with integration efficiency and suggests most intasome-binding events are unproductive.


Assuntos
Histonas/metabolismo , Integrases/metabolismo , Nucleossomos/metabolismo , Spumavirus/metabolismo , Proteínas Virais/metabolismo , Integração Viral , Domínio Catalítico , Cromatina/genética , Cromatina/metabolismo , DNA Viral/genética , DNA Viral/metabolismo , Genoma Viral , Humanos , Integrases/genética , Multimerização Proteica , Spumavirus/genética , Spumavirus/crescimento & desenvolvimento , Proteínas Virais/química , Proteínas Virais/genética
5.
Caries Res ; 56(4): 419-428, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36162361

RESUMO

Previous work has shown targeted fluorescent starch nanoparticles (TFSNs) can label the subsurface of carious lesions and assist dental professionals in the diagnostic process. In this study, we aimed to evaluate the potential of using artificial intelligence (AI) to detect and score carious lesions using ICDAS in combination with fluorescent imaging following application of TFSNs on teeth with a range of lesion severities, using ICDAS-labeled images as the reference standard. A total of 130 extracted human teeth with ICDAS scores from 0 to 6 were selected by a calibrated cariologist. Then, the same surface was imaged with a stereomicroscope under white light illumination, without visible fluorescence, and blue light illumination with an orange filter following application of the TFSNs. Both sets of images were labeled by another blinded ICDAS-calibrated cariologist to demarcate lesion position and severity. Convolutional neural networks, state-of-the-art models in imaging AI, were trained to determine the presence, location, ICDAS score (severity), and lesion surface porosity (as an indicator of activity) of carious lesions, and tested by 30 k-fold validation for white light, blue light, and the combined image sets. The best models showed high performance for the detection of carious lesions (sensitivity 80.26%, PPV 76.36%), potential for determining the severity via ICDAS scoring (accuracy 72%, SD 5.67%), and the detection of surface porosity as an indicator of the activity of the lesions (accuracy 90%, SD 7.00%). More broadly, the combination of targeted biopolymer nanoparticles with imaging AI is a promising combination of novel technologies that could be applied to many other applications.


Assuntos
Cárie Dentária , Nanopartículas , Humanos , Suscetibilidade à Cárie Dentária , Inteligência Artificial , Cárie Dentária/diagnóstico por imagem , Cárie Dentária/patologia , Redes Neurais de Computação
6.
Indian Pacing Electrophysiol J ; 22(2): 77-86, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34922032

RESUMO

BACKGROUND: Leadless pacemakers have been designed as an alternative to transvenous systems which avoid some of the complications associated with transvenous devices. We aim to perform a systematic review of the literature to report the safety and efficacy findings of leadless pacemakers. METHODS: We searched MEDLINE and EMBASE to identify studies reporting the safety, efficacy and outcomes of patients implanted with a leadless pacemaker. The pooled rate of adverse events was determined and random-effects meta-analysis was performed to compare rates of adverse outcomes for leadless compared to transvenous pacemakers. RESULTS: A total of 18 studies were included with 2496 patients implanted with a leadless pacemaker and success rates range between 95.5 and 100%. The device or procedure related death rate was 0.3% while any complication and pericardial tamponade occurred in 3.1% and 1.4% of patients, respectively. Other complications such as pericardial effusion, device dislodgement, device revision, device malfunction, access site complications and infection occurred in less than 1% of patients. Meta-analysis of four studies suggests that there was no difference in hematoma (RR 0.67 95%CI 0.21-2.18, 3 studies), pericardial effusion (RR 0.59 95%CI 0.15-2.25, 3 studies), device dislocation (RR 0.33 95%CI 0.06-1.74, 3 studies), any complication (RR 0.44 95%CI 0.17-1.09, 4 studies) and death (RR 0.45 95%CI 0.15-1.35, 2 studies) comparing patients who received leadless and transvenous pacemakers. CONCLUSION: Leadless pacemakers are safe and effective for patients who have an indication for single chamber ventricular pacing and the findings appear to be comparable to transvenous pacemakers.

7.
Platelets ; 32(7): 941-949, 2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-32897796

RESUMO

Hematological markers that can be rapidly analyzed and regularly monitored during a patient's stay on ICU, and that can identify bacterial causes of sepsis are being extensively sought. The significance of platelets in early immunological responses provides justification for assessing their usefulness in the identification of bacteremia amongst sepsis patients. In this preliminary study, the full blood count, including the platelet count by impedance (PLT-I), Immature Platelet Fraction (IPF%) and absolute immature platelet count (AIPC), were analyzed in eighty-two sepsis patients daily over the first 5 days stay on ICU. C-Reactive Protein (CRP), procalcitonin (PCT), and lactate were also analyzed daily. Blood cultures confirmed or excluded the presence of bacteremia. PCT provided the earliest indicator of bacteremia, with significant differences between the two cohorts on day 1. The change in IPF% and AIPC from day 1 to day 2 (Δ IPF% and Δ AIPC) provided the most accurate indication; A combination of Δ IPF% and day 2 PCT, provided a positive predictive value and negative predictive value of 100% and 96.10%, respectively. These data provide strong justification for larger multi-center validation studies to confirm the usefulness of these platelet indices during the assessment of sepsis on the ICU.


Assuntos
Bacteriemia/sangue , Plaquetas/metabolismo , Contagem de Plaquetas/métodos , Pró-Calcitonina/metabolismo , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino
8.
J Gen Intern Med ; 35(6): 1668-1677, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32193817

RESUMO

BACKGROUND: The United States Preventive Services Task Force recommends individualized breast cancer screening for average-risk women before age 50, advised by risk assessment and shared decision-making (SDM). However, the foundational principles of this recommendation that would inform decision support tools for patients and primary care physicians at the point of care have not been codified. Determining the core elements of SDM for breast cancer screening as valued by patients and primary care providers (PCPs) is necessary for implementing effective SDM tools. The aim of this study is to affirm core elements of SDM in the context of clinical interactions, through a Delphi consensus process. METHODS: A Delphi was conducted with 30 participants (10 women aged 40-49, 10 PCPs, and 10 healthcare decision scientists), to codify core elements of breast cancer screening SDM. The criterion for establishing consensus was a threshold of 80% agreement. The Delphi concluded with an 83% response rate. RESULTS: Of 48 items fielded, 44 met the threshold on the high-importance end of the response scale and were accepted as core elements. Core elements across three thematic categories-information delivery and patient education, interpersonal clinician-patient communication, and framework of the decision-received panelists' support in nearly equal measure. Panelists unanimously agreed that SDM should include provision of clearly understandable information, including that of personal breast cancer risk factors, and benefits and harms of mammography screening, and that PCPs should convey they are listening, knowledgeable, and demonstrate cultural sensitivity. DISCUSSION: This research codifies the core elements of SDM for mammography in women 40-49, augmenting the evidence to inform discussions between patients and physicians. These core elements of SDM have the potential to operationalize SDM for breast cancer screening in an effort to improve public health outcomes.


Assuntos
Neoplasias da Mama , Adulto , Neoplasias da Mama/diagnóstico , Tomada de Decisões , Tomada de Decisão Compartilhada , Detecção Precoce de Câncer , Feminino , Humanos , Pessoa de Meia-Idade , Participação do Paciente
9.
Int J Equity Health ; 19(1): 187, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33097061

RESUMO

BACKGROUND: In Australia, models of care have been developed to train antenatal care providers to promote oral health among pregnant women. However, these models are underpinned by Western values of maternity care that do not consider the cultural needs of Aboriginal and Torres Strait Islander women. This study aimed to explore the perceptions and experiences of Aboriginal health staff towards oral health care during pregnancy. It is part of a larger program of research to develop a new, culturally safe model of oral health care for Aboriginal women during pregnancy. METHODS: A descriptive qualitative methodology informed the study. Focus groups were convened to yarn with Aboriginal Health Workers, Family Partnership Workers and Aboriginal management staff at two antenatal health services in Sydney, Australia. RESULTS: A total of 14 people participated in the focus groups. There were four themes that were constructed. These focused on Aboriginal Health Workers and Family Partnership Workers identifying their role in promoting maternal oral health, where adequate training is provided and where trust has been developed with clients. Yet, because the Aboriginal health staff work in a system fundamentally driven by the legacy of colonisation, it has significantly contributed to the systemic barriers Aboriginal pregnant women continue to face in accessing health services, including dental care. The participants recommended that a priority dental referral pathway, that supported continuity of care, could provide increased accessibility to dental care. CONCLUSIONS: The Aboriginal health staff identified the potential role of Aboriginal Health Workers and Family Partnership Workers promoting oral health among Aboriginal pregnant women. To develop an effective oral health model of care among Aboriginal women during pregnancy, there is the need for training of Aboriginal Health Workers and Family Partnership Workers in oral health. Including Aboriginal staff at every stage of a dental referral pathway could reduce the fear of accessing mainstream health institutions and also promote continuity of care. Although broader oral health policies still need to be changed, this model could mitigate some of the barriers between Aboriginal women and both dental care providers and healthcare systems.


Assuntos
Pessoal de Saúde/psicologia , Serviços de Saúde do Indígena/organização & administração , Serviços de Saúde Materna/organização & administração , Havaiano Nativo ou Outro Ilhéu do Pacífico/psicologia , Saúde Bucal , Adulto , Austrália , Feminino , Grupos Focais , Pessoal de Saúde/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Modelos Organizacionais , Havaiano Nativo ou Outro Ilhéu do Pacífico/estatística & dados numéricos , Relações Médico-Paciente , Gravidez , Pesquisa Qualitativa , Confiança/psicologia , Adulto Jovem
10.
J Biol Chem ; 293(24): 9473-9485, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29674319

RESUMO

Conformations adopted by long stretches of single-stranded DNA (ssDNA) are of central interest in understanding the architecture of replication forks, R loops, and other structures generated during DNA metabolism in vivo This is particularly so if the ssDNA consists of short nucleotide repeats. Such studies have been hampered by the lack of defined substrates greater than ∼150 nt and the absence of high-resolution biophysical approaches. Here we describe the generation of very long ssDNA consisting of the mammalian telomeric repeat (5'-TTAGGG-3') n , as well as the interrogation of its structure by EM and single-molecule magnetic tweezers (smMT). This repeat is of particular interest because it contains a run of three contiguous guanine residues capable of forming G quartets as ssDNA. Fluorescent-dye exclusion assays confirmed that this G-strand ssDNA forms ubiquitous G-quadruplex folds. EM revealed thick bead-like filaments that condensed the DNA ∼12-fold. The bead-like structures were 5 and 8 nm in diameter and linked by thin filaments. The G-strand ssDNA displayed initial stability to smMT force extension that ultimately released in steps that were multiples ∼28 nm at forces between 6 and 12 pN, well below the >20 pN required to unravel G-quadruplexes. Most smMT steps were consistent with the disruption of the beads seen by EM. Binding by RAD51 distinctively altered the force extension properties of the G-strand ssDNA, suggesting a stochastic G-quadruplex-dependent condensation model that is discussed.


Assuntos
DNA de Cadeia Simples/química , DNA de Cadeia Simples/ultraestrutura , Quadruplex G , Sequência de Bases , DNA de Cadeia Simples/metabolismo , Humanos , Ligação Proteica , Rad51 Recombinase/metabolismo , Telômero/química , Telômero/metabolismo , Telômero/ultraestrutura
11.
J Biol Chem ; 293(37): 14285-14294, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30072380

RESUMO

Sliding clamps on DNA consist of evolutionarily conserved enzymes that coordinate DNA replication, repair, and the cellular DNA damage response. MutS homolog (MSH) proteins initiate mismatch repair (MMR) by recognizing mispaired nucleotides and in the presence of ATP form stable sliding clamps that randomly diffuse along the DNA. The MSH sliding clamps subsequently load MutL homolog (MLH/PMS) proteins that form a second extremely stable sliding clamp, which together coordinate downstream MMR components with the excision-initiation site that may be hundreds to thousands of nucleotides distant from the mismatch. Specific or nonspecific binding of other proteins to the DNA between the mismatch and the distant excision-initiation site could conceivably obstruct the free diffusion of these MMR sliding clamps, inhibiting their ability to initiate repair. Here, we employed bulk biochemical analysis, single-molecule fluorescence imaging, and mathematical modeling to determine how sliding clamps might overcome such hindrances along the DNA. Using both bacterial and human MSH proteins, we found that increasing the number of MSH sliding clamps on a DNA decreased the association of the Escherichia coli transcriptional repressor LacI to its cognate promoter LacO. Our results suggest a simple mechanism whereby thermal diffusion of MSH sliding clamps along the DNA alters the association kinetics of other DNA-binding proteins over extended distances. These observations appear generally applicable to any stable sliding clamp that forms on DNA.


Assuntos
DNA Bacteriano/metabolismo , Proteína MutS de Ligação de DNA com Erro de Pareamento/metabolismo , Thermus/metabolismo , Trifosfato de Adenosina/metabolismo , Pareamento Incorreto de Bases , Modelos Teóricos , Ligação Proteica , Ressonância de Plasmônio de Superfície
12.
BMC Health Serv Res ; 19(1): 474, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291959

RESUMO

BACKGROUND: Despite the high burden of pneumococcal disease, pneumococcal vaccine coverage continues to fall short of Healthy People 2020 goals. A quasi-experimental design was used to investigate the impact of pneumococcal-specific best-practice alerts (BPAs) with and without workflow redesign compared to health maintenance notifications only, on pneumococcal vaccination rates in at-risk and high-risk adults, and on series completion in immunocompetent adults aged 65+ years. METHODS: This retrospective study used electronic health record and administrative data to identify pneumococcal vaccinations using cross sectional and historical cohorts of adults age 19+ years from 2013 to 2017 who attended clinics associated with the University of Utah Health. Difference-in-differences (DD) analyses was used to assess the impact of interventions across three observation periods (Baseline, Interim, and Follow Up). Adherence to the 2-dose vaccination schedule in older adults was measured through a longitudinal analysis. RESULTS: In DD analyses, implementing both workflow redesign and the BPA raised the vaccination rate by 8 percentage points (pp) (P < 0.001) and implementing the BPA only raised the rate by 7 pp. (P < 0.001) among at-risk adults age 19-64 years, relative to implementing health maintenance notifications (i.e., usual care) only in comparison clinics. In high-risk adults age 19-64 years, the BPA with or without workflow redesign did not significantly affect vaccination rates from baseline to follow up relative to health maintenance notifications. Per DD analyses, the effect of the BPA was mixed in immunocompetent and immunocompromised adults age 65+ years. However, immunocompetent older adults attending a clinic that implemented the BPA plus health maintenance notifications and workflow redesign (all 3 interventions) had 1.94 times higher odds (Odds ratio (OR) 1.94; P = 0.0003, 95% CI 1.24, 3.01) to receive the second pneumococcal dose than patients attending a usual practice clinic (i.e., no intervention). CONCLUSIONS: A pneumococcal BPA tool that reflects current guidelines implemented with and without workflow redesign improved vaccination rates for at-risk adults age 19-64 years and increased the likelihood of adults aged 65+ to complete the recommended 2-dose series. However, in other adult patient groups, the BPA was not consistently associated with improvements in pneumococcal vaccination rates.


Assuntos
Vacinas Pneumocócicas/administração & dosagem , Guias de Prática Clínica como Assunto , Atenção Primária à Saúde , Sistemas de Alerta , Vacinação/estatística & dados numéricos , Adulto , Idoso , Estudos Transversais , Registros Eletrônicos de Saúde , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Esquemas de Imunização , Masculino , Pessoa de Meia-Idade , Infecções Pneumocócicas/prevenção & controle , Estudos Retrospectivos , Medição de Risco , Adulto Jovem
13.
BMC Public Health ; 18(1): 381, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29558933

RESUMO

BACKGROUND: Early childhood caries is the most common chronic childhood disease worldwide. Australian Aboriginal and Torres Strait Islander children are twice more likely to develop dental decay, and contributing factors include poor maternal oral health and underutilisation of dental services. Globally, Indigenous health workers are in a unique position to deliver culturally competent oral healthcare because they have a contextual understanding of the needs of the community. METHODS: This scoping review aimed to identify the role of Indigenous health workers in promoting maternal oral health globally. A systematic search was undertaken of six electronic databases for relevant published literature and grey literature, and expanded to include non-dental health professionals and other Indigenous populations across the lifespan when limited studies were identified. RESULTS: Twenty-two papers met the inclusion criteria, focussing on the role of Indigenous health workers in maternal oral healthcare, types of oral health training programs and screening tools to evaluate program effectiveness. There was a paucity of peer-reviewed evidence on the role of Indigenous health workers in promoting maternal oral health, with most studies focusing on other non-dental health professionals. Nevertheless, there were reports of Indigenous health workers supporting oral health in early childhood. Although some oral health screening tools and training programs were identified for non-dental health professionals during the antenatal period, no specific screening tool has been developed for use by Indigenous health workers. CONCLUSIONS: While the role of health workers from Indigenous communities in promoting maternal oral health is yet to be clearly defined, they have the potential to play a crucial role in 'driving' screening and education of maternal oral health especially when there is adequate organisational support, warranting further research.


Assuntos
Promoção da Saúde/organização & administração , Serviços de Saúde do Indígena , Havaiano Nativo ou Outro Ilhéu do Pacífico , Saúde Bucal/etnologia , Papel Profissional , Austrália , Feminino , Humanos , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Genet Med ; 18(7): 705-11, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26583685

RESUMO

PURPOSE: Researchers' obligations to disclose genetic incidental findings (GIFs) have been widely debated, but there has been little empirical study of the engagement of institutional review boards (IRBs) with this issue. METHODS: This article presents data from the first extensive (n = 796) national survey of IRB professionals' understanding of, experience with, and beliefs surrounding GIFs. RESULTS: Most respondents had dealt with questions about GIFs (74%), but only a minority (47%) felt prepared to address them. Although a majority believed that there is an obligation to disclose GIFs (78%), there is still not consensus about the supporting ethical principles. Respondents generally did not endorse the idea that researchers' additional time and effort (7%), and lack of resources (29%), were valid reasons for diminishing a putative obligation. Most (96%) supported a right not to know, but this view became less pronounced (63%) when framed in terms of specific case studies. CONCLUSIONS: IRBs are actively engaged with GIFs but have not yet reached consensus. Respondents were uncomfortable with arguments that could be used to limit an obligation to return GIFs. This could indicate that IRBs are providing some of the impetus for the trend toward returning GIFs, although questions remain about the relative contribution of other stakeholders.Genet Med 18 7, 705-711.


Assuntos
Revelação/ética , Ética em Pesquisa , Pesquisa em Genética/ética , Achados Incidentais , Comitês de Ética em Pesquisa , Humanos , Consentimento Livre e Esclarecido/ética , Pesquisadores/ética
15.
Environ Microbiol ; 17(11): 4779-89, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26373338

RESUMO

Multicellular biofilms are an ancient bacterial adaptation that offers a protective environment for survival in hostile habitats. In microaerophilic organisms such as Campylobacter, biofilms play a key role in transmission to humans as the bacteria are exposed to atmospheric oxygen concentrations when leaving the reservoir host gut. Genetic determinants of biofilm formation differ between species, but little is known about how strains of the same species achieve the biofilm phenotype with different genetic backgrounds. Our approach combines genome-wide association studies with traditional microbiology techniques to investigate the genetic basis of biofilm formation in 102 Campylobacter jejuni isolates. We quantified biofilm formation among the isolates and identified hotspots of genetic variation in homologous sequences that correspond to variation in biofilm phenotypes. Thirteen genes demonstrated a statistically robust association including those involved in adhesion, motility, glycosylation, capsule production and oxidative stress. The genes associated with biofilm formation were different in the host generalist ST-21 and ST-45 clonal complexes, which are frequently isolated from multiple host species and clinical samples. This suggests the evolution of enhanced biofilm from different genetic backgrounds and a possible role in colonization of multiple hosts and transmission to humans.


Assuntos
Biofilmes/crescimento & desenvolvimento , Campylobacter jejuni/genética , Patrimônio Genético , Variação Genética/genética , Evolução Biológica , Campylobacter jejuni/classificação , Campylobacter jejuni/isolamento & purificação , Estudo de Associação Genômica Ampla , Humanos , Oxigênio/metabolismo
16.
Nucleic Acids Res ; 41(11): 5887-97, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23609540

RESUMO

Escherichia coli Exonuclease I (ExoI) digests single-stranded DNA (ssDNA) in the 3'-5' direction in a highly processive manner. The crystal structure of ExoI, determined previously in the absence of DNA, revealed a C-shaped molecule with three domains that form a central positively charged groove. The active site is at the bottom of the groove, while an extended loop, proposed to encircle the DNA, crosses over the groove. Here, we present crystal structures of ExoI in complex with four different ssDNA substrates. The structures all have the ssDNA bound in essentially the predicted manner, with the 3'-end in the active site and the downstream end under the crossover loop. The central nucleotides of the DNA form a prominent bulge that contacts the SH3-like domain, while the nucleotides at the downstream end of the DNA form extensive interactions with an 'anchor' site. Seven of the complexes are similar to one another, but one has the ssDNA bound in a distinct conformation. The highest-resolution structure, determined at 1.95 Å, reveals an Mg(2+) ion bound to the scissile phosphate in a position corresponding to Mg(B) in related two-metal nucleases. The structures provide new insights into the mechanism of processive digestion that will be discussed.


Assuntos
DNA de Cadeia Simples/química , Proteínas de Escherichia coli/química , Exodesoxirribonucleases/química , Domínio Catalítico , Cristalografia por Raios X , Magnésio/química , Modelos Moleculares
17.
J Invertebr Pathol ; 129: 45-56, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26031565

RESUMO

A new microsporidian genus and species, Myrmecomorba nylanderiae, is described from North American populations of the tawny crazy ant, Nylanderia fulva. This new species was found to be heterosporous producing several types of binucleate spores in both larval and adult stages and an abortive octosporoblastic sporogony in adult ants. While microsporidia are widespread arthropod parasites, this description represents only the fifth species described from an ant host. Molecular analysis indicated that this new taxon is phylogenetically closely allied to the microsporidian family Caudosporidae, a group known to parasitize aquatic black fly larvae. We report the presence of 3 spore types (Type 1 DK, Type 2 DK, and octospores) with infections found in all stages of host development and reproductive castes. This report documents the first pathogen infecting N. fulva, an invasive ant of considerable economic and ecological consequence.


Assuntos
Formigas/parasitologia , Microsporídios/fisiologia , Animais , Genes Fúngicos/genética , Filogenia , Reação em Cadeia da Polimerase
18.
Proc Natl Acad Sci U S A ; 109(38): 15395-400, 2012 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-22949669

RESUMO

Sensitive detection of low-abundance proteins in complex biological samples has typically been achieved by immunoassays that use antibodies specific to target proteins; however, de novo development of antibodies is associated with high costs, long development lead times, and high failure rates. To address these challenges, we developed an antibody-free strategy that involves PRISM (high-pressure, high-resolution separations coupled with intelligent selection and multiplexing) for sensitive selected reaction monitoring (SRM)-based targeted protein quantification. The strategy capitalizes on high-resolution reversed-phase liquid chromatographic separations for analyte enrichment, intelligent selection of target fractions via on-line SRM monitoring of internal standards, and fraction multiplexing before nano-liquid chromatography-SRM quantification. Application of this strategy to human plasma/serum demonstrated accurate and reproducible quantification of proteins at concentrations in the 50-100 pg/mL range, which represents a major advance in the sensitivity of targeted protein quantification without the need for specific-affinity reagents. Application to a set of clinical serum samples illustrated an excellent correlation between the results obtained from the PRISM-SRM assay and those from clinical immunoassay for the prostate-specific antigen level.


Assuntos
Anticorpos/química , Espectrometria de Massas/métodos , Proteínas/análise , Animais , Biomarcadores/metabolismo , Proteínas Sanguíneas/análise , Calibragem , Anidrases Carbônicas/sangue , Bovinos , Cromatografia Líquida/métodos , Feminino , Humanos , Antígeno Prostático Específico/sangue , Proteômica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Biologia de Sistemas/métodos
19.
Drug Metab Dispos ; 42(4): 529-36, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24459179

RESUMO

The UDP-glucuronosyltransferase (UGT) 2B subfamily of enzymes plays an important role in the metabolism of numerous endogenous and exogenous compounds, including various carcinogens present in tobacco smoke. The goal of the present study was to examine the levels of expression of individual UGT2B genes in various tissues that are targets for tobacco carcinogenesis. Using MT-ATP6 as the experimentally validated housekeeping gene, the highest extrahepatic expression of UGT2B genes was observed in human tonsil, with UGT2B expression levels similar to that observed in human liver. UGT2B17 exhibited high relative expression in most tissues examined, including lung, most tissues of the aerodigestive tract, and pancreas. UGT2B7 expression was highest in pancreas but low or undetectable in most other tissues examined. UGT2B10 expression was high in both tonsil and tongue. There was wide variability between individuals in the magnitude of expression in each tissue site, and there were strong correlations between UGT2B expression levels in different individuals within many of the tissue sites, suggesting coordinated regulation of UGT2B gene expression in extrahepatic tissues. In the liver, UGTs 2B4, 2B7, 2B10, and 2B15 were significantly correlated with each other (all r(2) > 0.70, P < 0.0001). In all examined tissues of the aerodigestive tract, UGTs 2B10, 2B11, and 2B17 exhibited a strong correlation with each other (all r(2) > 0.75, P < 0.05). UGTs 2B7 and 2B10 exhibited a strong inverse correlation in the pancreas (r(2) = -0.95, P < 0.01). These data suggest that specific UGT2B enzymes important in tobacco carcinogen metabolism are expressed and coordinately regulated in various target sites for tobacco-related cancers.


Assuntos
Carcinógenos/farmacocinética , Regulação Enzimológica da Expressão Gênica , Glucuronosiltransferase/genética , Nicotiana/metabolismo , Perfilação da Expressão Gênica , Humanos , Limite de Detecção , Especificidade de Órgãos , Nicotiana/toxicidade
20.
Am J Public Health ; 104 Suppl 4: S572-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25100423

RESUMO

OBJECTIVES: We examined national trends in smoke-free home rules among U.S. veterans and nonveterans. METHODS: We used data from the 2001-2002 and 2010-2011 Tobacco Use Supplement to the Current Population Survey to estimate and compare the existence of smoke-free home rules among veterans and nonveterans for each survey period. RESULTS: The prevalence of a complete smoke-free home rule among veterans increased from 64.0% to 79.7% between 2001 and 2011 (P < .01) but was consistently lower than were rates estimated for nonveterans (67.6% and 84.4%, respectively). Disparities between the 2 groups increased significantly over time (P < .05). CONCLUSIONS: Despite the general increase in the adoption of smoke-free home rules, veterans lag behind the rest of the U.S. population. Interventions promoting the adoption of complete smoke-free home rules are necessary to protect veterans and their families and to reduce disparities.


Assuntos
Habitação/estatística & dados numéricos , Fumar/epidemiologia , Poluição por Fumaça de Tabaco/estatística & dados numéricos , Veteranos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores Socioeconômicos , Estados Unidos , Saúde dos Veteranos , Adulto Jovem
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