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Ebselen is a drug in clinical trials for several diseases and degenerative conditions where oxidative stress is implicated. A series of novel ebselen analogues was synthesized, including hydroxy-, alkoxy- and aminomethylene derivatives, as well as hybrid species where the ebselen selenium atom is shared with other potent antioxidant structures, such as cyclic selenenyl sulfide, cyclic seleninate ester and spirodioxyselenurane moieties. Conjugates of ebselen with cholesterol, prednisolone and the radical inhibitor BHT were also prepared. The products were tested for antioxidant activity in an NMR-based assay by measuring the rate of consumption of benzyl thiol or the production of dibenzyl disulfide in the presence of hydrogen peroxide when catalyzed by the ebselen analogues. Activities ranged from 12 to 0.12 times that of ebselen. The oxidation of the 2-hydroxymethylene derivative of ebselen was faster than thiolysis in the initial step and the overall rate was further accelerated under basic conditions. The corresponding selenenyl sulfide analogue underwent very slow disproportionation under neutral conditions that was enhanced by the presence of a base catalyst. During investigation of possible fluxional behaviour of a bis-amide analogue, an unusual tetraphenyphosphonium salt of a tricoordinate selenium pincer anion was discovered with exceptionally potent catalytic activity, 130 times that of ebselen. In addition to rate measurements, X-ray crystallography and DFT computational methods were also employed to gain further structural and mechanistic insights.
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BACKGROUND: Vibrio spp. are a diverse group of ecologically important marine bacteria responsible for several foodborne outbreaks of gastroenteritis around the world. Their detection and characterization are moving away from conventional culture-based methods towards next generation sequencing (NGS)-based approaches. However, genomic methods are relative in nature and suffer from technical biases arising from library preparation and sequencing. Here, we introduce a quantitative NGS-based method that enables the quantitation of Vibrio spp. at the limit of quantification (LOQ) through artificial DNA standards and their absolute quantification via digital PCR (dPCR). RESULTS: We developed six DNA standards, called Vibrio-Sequins, together with optimized TaqMan assays for their quantification in individually sequenced DNA libraries via dPCR. To enable Vibrio-Sequin quantification, we validated three duplex dPCR methods to quantify the six targets. LOQs were ranging from 20 to 120 cp/µl for the six standards, whereas the limit of detection (LOD) was ~ 10 cp/µl for all six assays. Subsequently, a quantitative genomics approach was applied to quantify Vibrio-DNA in a pooled DNA mixture derived from several Vibrio species in a proof-of-concept study, demonstrating the increased power of our quantitative genomic pipeline through the coupling of NGS and dPCR. CONCLUSIONS: We significantly advance existing quantitative (meta)genomic methods by ensuring metrological traceability of NGS-based DNA quantification. Our method represents a useful tool for future metagenomic studies aiming at quantifying microbial DNA in an absolute manner. The inclusion of dPCR into sequencing-based methods supports the development of statistical approaches for the estimation of measurement uncertainties (MU) for NGS, which is still in its infancy.
Assuntos
DNA , Genômica , Reação em Cadeia da Polimerase/métodos , DNA/genética , Sequência de BasesRESUMO
Through sustainable development goals 3 and 8 and other policies, countries have committed to protect and promote workers' health by reducing the work-related burden of disease. To monitor progress on these commitments, indicators that capture the work-related burden of disease should be available for monitoring workers' health and sustainable development. The World Health Organization and the International Labour Organization estimate that only 363 283 (19%) of 1 879 890 work-related deaths globally in 2016 were due to injuries, whereas 1 516 607 (81%) deaths were due to diseases. Most monitoring systems focusing on workers' health or sustainable development, such as the global indicator framework for the sustainable development goals, include an indicator on the burden of occupational injuries. Few such systems, however, have an indicator on the burden of work-related diseases. To address this gap, we present a new global indicator: mortality rate from diseases attributable to selected occupational risk factors, by disease, risk factor, sex and age group. We outline the policy rationale of the indicator, describe its data sources and methods of calculation, and report and analyse the official indicator for 183 countries. We also provide examples of the use of the indicator in national workers' health monitoring systems and highlight the indicator's strengths and limitations. We conclude that integrating the new indicator into monitoring systems will provide more comprehensive and accurate surveillance of workers' health, and allow harmonization across global, regional and national monitoring systems. Inequalities in workers' health can be analysed and the evidence base can be improved towards more effective policy and systems on workers' health.
Par le biais des objectifs de développement durable 3 et 8 ainsi que d'autres mesures, plusieurs pays se sont engagés à protéger et promouvoir la santé des travailleurs en réduisant l'impact des maladies liées au travail. Mais pour évaluer leurs progrès en la matière, il convient de mettre en place des indicateurs estimant l'impact des maladies liées au travail afin de placer le développement durable et la santé des travailleurs sous surveillance. D'après l'Organisation mondiale de la Santé et l'Organisation internationale du Travail, seulement 363 283 (19%) des 1 879 890 décès liés au travail dans le monde en 2016 découlaient de blessures, tandis que 1 516 607 (81%) d'entre eux étaient causés par des maladies. La plupart des systèmes de surveillance qui s'intéressent à la santé des travailleurs ou au développement durable, comme le cadre mondial d'indicateurs pour les objectifs de développement durable, comportent un indicateur relatif à l'impact des accidents de travail. Cependant, rares sont ceux qui possèdent un indicateur concernant l'impact des maladies professionnelles. Pour combler cette lacune, nous dévoilons un nouvel indicateur mondial: le taux de mortalité dû aux maladies attribuables à certains facteurs de risque professionnels classé par maladie, facteur de risque, sexe et catégorie d'âge. Nous exposons le motif politique de l'indicateur, décrivons l'origine des données et les méthodes de calcul, et communiquons et analysons l'indicateur officiel pour 183 pays. Nous fournissons également des exemples de la façon dont l'indicateur peut être utilisé dans des systèmes nationaux de surveillance de la santé des travailleurs et soulignons ses forces et faiblesses. Nous concluons en affirmant que l'intégration de ce nouvel indicateur dans les systèmes de surveillance offrira un suivi plus complet et précis de la santé des travailleurs et ouvrira la voie à une harmonisation des systèmes mondiaux, nationaux et régionaux. Il est possible d'analyser les inégalités en matière de santé des travailleurs et d'en améliorer les bases factuelles afin d'établir des politiques et systèmes plus efficaces dans ce domaine.
A través de los objetivos de desarrollo sostenible 3 y 8 y de otras políticas, los países se han comprometido a proteger y promover la salud de los trabajadores reduciendo la carga de morbilidad relacionada con el trabajo. Para supervisar los avances en el cumplimiento de estos compromisos, debería disponerse de indicadores que reflejen la carga de morbilidad relacionada con el trabajo, a fin de controlar la salud de los trabajadores y el desarrollo sostenible. La Organización Mundial de la Salud y la Organización Internacional del Trabajo estiman que solo 363 283 (19%) de las 1 879 890 muertes relacionadas con el trabajo a nivel mundial en 2016 se debieron a lesiones, mientras que 1 516 607 (81%) muertes se debieron a enfermedades. La mayoría de los sistemas de vigilancia centrados en la salud de los trabajadores o el desarrollo sostenible, como el marco de indicadores mundiales para los objetivos de desarrollo sostenible, incluyen un indicador sobre la carga de las lesiones laborales. No obstante, pocos de estos sistemas cuentan con un indicador sobre la carga de las enfermedades relacionadas con el trabajo. Para subsanar esta carencia, presentamos un nuevo indicador mundial: la tasa de mortalidad por enfermedades atribuibles a factores de riesgo laborales seleccionados, por enfermedad, factor de riesgo, sexo y grupo de edad. Describimos la justificación política del indicador, describimos sus fuentes de datos y métodos de cálculo, e informamos y analizamos el indicador oficial para 183 países. También proporcionamos ejemplos del uso del indicador en los sistemas nacionales de vigilancia de la salud de los trabajadores y destacamos las ventajas y las limitaciones del indicador. Concluimos que la integración del nuevo indicador en los sistemas de vigilancia proporcionará una vigilancia más exhaustiva y precisa de la salud de los trabajadores, y permitirá la armonización entre los sistemas de vigilancia mundiales, regionales y nacionales. Se podrán analizar las desigualdades en la salud de los trabajadores y se podrá mejorar la base de evidencias para lograr políticas y sistemas más eficaces en materia de salud de los trabajadores.
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Saúde Ocupacional , Humanos , Fatores de Risco , Desenvolvimento Sustentável , Políticas , Saúde GlobalRESUMO
The antioxidant drug ebselen has been widely studied in both laboratories and in clinical trials. The catalytic mechanism by which it destroys hydrogen peroxide via reduction with glutathione or other thiols is complex and has been the subject of considerable debate. During reinvestigations of several key steps, we found that the seleninamide that comprises the first oxidation product of ebselen underwent facile reversible methanolysis to an unstable seleninate ester and two dimeric products. In its reaction with benzyl alcohol, the seleninamide produced a benzyl ester that reacted readily by selenoxide elimination, with formation of benzaldehyde. Oxidation of ebselen seleninic acid did not afford a selenonium seleninate salt as previously observed with benzene seleninic acid, but instead generated a mixture of the seleninic and selenonic acids. Thiolysis of ebselen with benzyl thiol was faster than oxidation by ca. an order of magnitude and produced a stable selenenyl sulfide. When glutathione was employed, the product rapidly disproportionated to glutathione disulfide and ebselen diselenide. Oxidation of the S-benzyl selenenyl sulfide, or thiolysis of the seleninamide with benzyl thiol, afforded a transient thiolseleninate that also readily underwent selenoxide elimination. The S-benzyl derivative disproportionated readily when catalyzed by the simultaneous presence of both the thiol and triethylamine. The phenylthio analogue disproportionated when exposed to ambient or UV (360 nm) light by a proposed radical mechanism. These observations provide additional insight into several reactions and intermediates related to ebselen.
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Antioxidantes , Compostos Organosselênicos , Glutationa Peroxidase/metabolismo , Isoindóis , Oxirredução , Catálise , Glutationa , Sulfetos , Ésteres , Compostos de Sulfidrila , AzóisRESUMO
During attempts to prepare spirodithiaselenuranes as GPx mimetics, a series of unexpected dimeric macrocycles was obtained, each containing two selenide and two disulfide moieties in rings ranging from 18- to 26-membered. The products showed potent GPx-like activity in an NMR assay based on their ability to catalyze the reduction of hydrogen peroxide with benzyl thiol. The high catalytic activity was attributed to transannular effects during selenide to selenoxide oxidation. This redox process was also characterized by an induction period that indicated autocatalysis in the formation of an intermediate selenoxide from the oxidation of the corresponding selenide.
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Antioxidantes , Compostos Organosselênicos , Antioxidantes/farmacologia , Antioxidantes/química , Compostos Organosselênicos/química , Glutationa Peroxidase/metabolismo , Dissulfetos , Oxirredução , Peróxido de Hidrogênio/químicaRESUMO
The synthesis of aryl selenonic acids was achieved from diverse aryl bromides via a one-pot method involving metalation, selenation, and oxidation with hydrogen peroxide followed by ion exchange to afford the pure products in 77-90% yield. An o-hydroxymethyl derivative was found to dehydrate readily, affording the first example of a cyclic selenonic ester, while two minor byproducts were isolated and shown by X-ray crystallography to be mixed salts of aryl selenonic acids with either the corresponding aryl seleninic or selenious acid.
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Brometos , Sais , OxirreduçãoRESUMO
The advanced radiographic capability (ARC) laser system, part of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, is a short-pulse laser capability integrated into the NIF. The ARC is designed to provide adjustable pulse lengths of â¼1-38ps in four independent beamlets, each with energies up to 1 kJ (depending on pulse duration). A detailed model of the ARC lasers has been developed that predicts the time- and space-resolved focal spots on target for each shot. Measurements made to characterize static and dynamic wavefront characteristics of the ARC are important inputs to the code. Modeling has been validated with measurements of the time-integrated focal spot at the target chamber center (TCC) at low power, and the space-integrated pulse duration at high power, using currently available diagnostics. These simulations indicate that each of the four ARC beamlets achieves a peak intensity on target of up to a few 1018W/cm2.
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Benzeneperoxyseleninic acid has been proposed as the key intermediate in the widely used epoxidation of alkenes with benzeneseleninic acid and hydrogen peroxide. However, it reacts sluggishly with cyclooctene and instead rapidly decomposes in solution to a mixed selenonium-selenonate salt that was identified by X-ray absorption and 77 Seâ NMR spectroscopy, as well as by single crystal X-ray diffraction. This process includes a selenoxide elimination of the peroxyseleninic acid with liberation of oxygen and additional redox steps. The salt is relatively stable in the solid state, but generates the corresponding selenonic acid in the presence of hydrogen peroxide. The selenonic acid is inert towards cyclooctene on its own; however, rapid epoxidation occurs when hydrogen peroxide is added. This shows that the selenonic acid must first be activated through further oxidation, presumably to the heretofore unknown benzeneperoxyselenonic acid. The latter is the principal oxidant in this epoxidation.
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Selenium compounds play an important role in redox homeostasis in living organisms. One of their major functions is to suppress the harmful effects of hydrogen peroxide, hydroperoxides and downstream reactive oxygen species that lead to oxidative stress, which has in turn been implicated in many diseases and degenerative conditions. The glutathione peroxidase (GPx) family of selenoenzymes plays a key protective role by catalyzing the reduction of peroxides with glutathione. Considerable effort has been expended toward the discovery of small-molecule selenium compounds that mimic GPx. To date, ebselen has been the most widely studied such compound, including in several clinical trials. However, despite its proven lack of significant toxicity, it displays only moderate catalytic activity and very poor aqueous solubility. The cyclic seleninate esters and spirodioxyselenuranes have recently been investigated as potential next generation GPx mimetics, along with structurally related selenenate esters, diazaselenuranes and pincer selenuranes. Their catalytic activities, redox mechanisms and structure-activity relationships are described in this Review, along with a description and discussion of the relative merits of assays for measuring their activities.
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Azóis/química , Glutationa Peroxidase/química , Glutationa/química , Peróxido de Hidrogênio/química , Compostos Organosselênicos/química , Compostos de Selênio/química , Catálise , Ésteres , Glutationa Peroxidase/metabolismo , Isoindóis , Estresse Oxidativo , Espécies Reativas de Oxigênio , Compostos de Selênio/metabolismoRESUMO
The chemical parameters and the functionalities of six monofloral honeys of different botanical and geographical origins were investigated. Vitamins B1, B2, and C and the protein content of majority of honeys were distinguishable from general honey. Honeys not only were rich in a variety of functional components like flavonoids but also had strong anti-oxidant activities, scavenging activities against ROS, and anti-hypertensive and anti-allergic activities. Honeys were heated at 100 °C for 24 h and their browning intensity during heating process was observed to vary with botanical origin. The functional properties of caramelization and maillard reaction (MR) products derived from honeys during heating were evaluated. The browning of honeys progressed regardless of honey species. Anti-oxidant activities and scavenging activities against superoxide and DPPH radicals of products drastically increased, but ACE and hyaluronidase activities gradually decreased with passage of heating time. It concluded that the products, mainly melanoidins, produced simultaneously to browning process in caramelization and MR contributed to the expression of its useful function.
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BACKGROUND: Risk stratification is a major challenge in bladder cancer (BC), and a biomarker is needed. Multiple studies have reported the neutrophil-to-lymphocyte ratio (NLR) as a promising candidate; however, these analyses have methodological limitations. Therefore, the authors performed a category B biomarker study to test whether NLR is prognostic for overall survival (OS) after curative treatment or is predictive for the survival benefit from neoadjuvant chemotherapy (NAC). METHODS: This study is an unplanned secondary analysis of SWOG 8710, a randomized phase 3 trial that assessed cystectomy with or without NAC in 317 patients with muscle-invasive BC. NLR was calculated from prospectively collected complete blood counts. For the prognostic analysis, 230 patients were identified; for the predictive analysis, 263 were identified. NLR was evaluated with proportional hazards models including prespecified factors (age, sex, T-stage, lymphovascular invasion, and treatment arm). RESULTS: With a median follow-up of 18.6 years, there were 172 and 205 deaths in the prognostic and predictive cohorts, respectively. In a multivariable analysis, NLR was not prognostic for OS (hazard ratio [HR], 1.04; 95% confidence interval [CI], 0.98-1.11; P = .24). Furthermore, NLR did not predict for the OS benefit from NAC (HR, 1.01; 95% CI, 0.90-1.14; P = .86). Factors associated with worse OS were older age (HR, 1.05; 95% CI, 1.04-1.07; P < .001) and surgery without NAC (HR, 1.39; 95% CI, 1.03-1.88; P = .03). CONCLUSIONS: This is the first analysis of NLR in BC to use prospectively collected clinical trial data. In contrast to previous studies, it suggests that NLR is neither a prognostic nor predictive biomarker for OS in muscle-invasive BC. Cancer 2017;123:794-801. © 2016 American Cancer Society.
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Biomarcadores Tumorais/sangue , Contagem de Células Sanguíneas , Prognóstico , Neoplasias da Bexiga Urinária/sangue , Idoso , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neutrófilos/patologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologiaRESUMO
Speciation often involves repeated episodes of genetic contact between divergent populations before reproductive isolation (RI) is complete. Whole-genome sequencing (WGS) holds great promise for unravelling the genomic bases of speciation. We have studied two ecologically divergent, hybridizing species of the 'model tree' genus Populus (poplars, aspens, cottonwoods), Populus alba and P. tremula, using >8.6 million single nucleotide polymorphisms (SNPs) from WGS of population pools. We used the genomic data to (i) scan these species' genomes for regions of elevated and reduced divergence, (ii) assess key aspects of their joint demographic history based on genomewide site frequency spectra (SFS) and (iii) infer the potential roles of adaptive and deleterious coding mutations in shaping the genomic landscape of divergence. We identified numerous small, unevenly distributed genome regions without fixed polymorphisms despite high overall genomic differentiation. The joint SFS was best explained by ancient and repeated gene flow and allowed pinpointing candidate interspecific migrant tracts. The direction of selection (DoS) differed between genes in putative migrant tracts and the remainder of the genome, thus indicating the potential roles of adaptive divergence and segregating deleterious mutations on the evolution and breakdown of RI. Genes affected by positive selection during divergence were enriched for several functionally interesting groups, including well-known candidate 'speciation genes' involved in plant innate immunity. Our results suggest that adaptive divergence affects RI in these hybridizing species mainly through intrinsic and demographic processes. Integrating genomic with molecular data holds great promise for revealing the effects of particular genetic pathways on speciation.
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Evolução Molecular , Fluxo Gênico , Populus/genética , Isolamento Reprodutivo , Genoma de Planta , Genômica , Polimorfismo de Nucleotídeo Único , Populus/classificação , Seleção Genética , Análise de Sequência de DNA , Árvores/classificação , Árvores/genéticaRESUMO
Natural hybrid zones have proven to be precious tools for understanding the origin and maintenance of reproductive isolation (RI) and therefore species. Most available genomic studies of hybrid zones using whole- or partial-genome resequencing approaches have focused on comparisons of the parental source populations involved in genome admixture, rather than exploring fine-scale patterns of chromosomal ancestry across the full admixture gradient present between hybridizing species. We have studied three well-known European 'replicate' hybrid zones of Populus alba and P. tremula, two widespread, ecologically divergent forest trees, using up to 432 505 single-nucleotide polymorphisms (SNPs) from restriction site-associated DNA (RAD) sequencing. Estimates of fine-scale chromosomal ancestry, genomic divergence and differentiation across all 19 poplar chromosomes revealed strikingly contrasting results, including an unexpected preponderance of F1 hybrids in the centre of genomic clines on the one hand, and genomically localized, spatially variable shared variants consistent with ancient introgression between the parental species on the other. Genetic ancestry had a significant effect on survivorship of hybrid seedlings in a common garden trial, pointing to selection against early-generation recombinants. Our results indicate a role for selection against recombinant genotypes in maintaining RI in the face of apparent F1 fertility, consistent with the intragenomic 'coadaptation' model of barriers to introgression upon secondary contact. Whole-genome resequencing of hybridizing populations will clarify the roles of specific genetic pathways in RI between these model forest trees and may reveal which loci are affected most strongly by its cyclic breakdown.
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Fluxo Gênico , Hibridização Genética , Populus/genética , Isolamento Reprodutivo , Seleção Genética , DNA de Cloroplastos/genética , DNA de Plantas/genética , Fertilidade , Genética Populacional , Genoma de Planta , Genótipo , Haplótipos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNARESUMO
Governments worldwide are recognising ecosystem services as an approach to address sustainability challenges. Decision-makers need credible and legitimate measurements of ecosystem services to evaluate decisions for trade-offs to make wise choices. Managers lack these measurements because of a data gap linking ecosystem characteristics to final ecosystem services. The dominant method to address the data gap is benefit transfer using ecological data from one location to estimate ecosystem services at other locations with similar land cover. However, benefit transfer is only valid once the data gap is adequately resolved. Disciplinary frames separating ecology from economics and policy have resulted in confusion on concepts and methods preventing progress on the data gap. In this study, we present a 10-step approach to unify concepts, methods and data from the disparate disciplines to offer guidance on overcoming the data gap. We suggest: (1) estimate ecosystem characteristics using biophysical models, (2) identify final ecosystem services using endpoints and (3) connect them using ecological production functions to quantify biophysical trade-offs. The guidance is strategic for public policy because analysts need to be: (1) realistic when setting priorities, (2) attentive to timelines to acquire relevant data, given resources and (3) responsive to the needs of decision-makers.
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Conservação dos Recursos Naturais/economia , Tomada de Decisões , Ecossistema , Política Pública , Ecologia/métodos , Modelos Teóricos , Formulação de PolíticasRESUMO
Studying the divergence continuum in plants is relevant to fundamental and applied biology because of the potential to reveal functionally important genetic variation. In this context, whole-genome sequencing (WGS) provides the necessary rigour for uncovering footprints of selection. We resequenced populations of two divergent phylogeographic lineages of Populus alba (n = 48), thoroughly characterized by microsatellites (n = 317), and scanned their genomes for regions of unusually high allelic differentiation and reduced diversity using > 1.7 million single nucleotide polymorphisms (SNPs) from WGS. Results were confirmed by Sanger sequencing. On average, 9134 high-differentiation (≥ 4 standard deviations) outlier SNPs were uncovered between populations, 848 of which were shared by ≥ three replicate comparisons. Annotation revealed that 545 of these were located in 437 predicted genes. Twelve percent of differentiation outlier genome regions exhibited significantly reduced genetic diversity. Gene ontology (GO) searches were successful for 327 high-differentiation genes, and these were enriched for 63 GO terms. Our results provide a snapshot of the roles of 'hard selective sweeps' vs divergent selection of standing genetic variation in distinct postglacial recolonization lineages of P. alba. Thus, this study adds to our understanding of the mechanisms responsible for the origin of functionally relevant variation in temperate trees.
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Florestas , Variação Genética , Genoma de Planta , Camada de Gelo , Filogenia , Populus/genética , Seleção Genética , Árvores/genética , Ontologia Genética , Genes de Plantas , Estudos de Associação Genética , Hungria , Itália , Repetições de Microssatélites/genética , Polimorfismo de Nucleotídeo Único/genética , Reprodutibilidade dos Testes , Análise de Sequência de DNARESUMO
BACKGROUND: High-throughput sequencing has opened up exciting possibilities in population and conservation genetics by enabling the assessment of genetic variation at genome-wide scales. One approach to reduce genome complexity, i.e. investigating only parts of the genome, is reduced-representation library (RRL) sequencing. Like similar approaches, RRL sequencing reduces ascertainment bias due to simultaneous discovery and genotyping of single-nucleotide polymorphisms (SNPs) and does not require reference genomes. Yet, generating such datasets remains challenging due to laboratory and bioinformatical issues. In the laboratory, current protocols require improvements with regards to sequencing homologous fragments to reduce the number of missing genotypes. From the bioinformatical perspective, the reliance of most studies on a single SNP caller disregards the possibility that different algorithms may produce disparate SNP datasets. RESULTS: We present an improved RRL (iRRL) protocol that maximizes the generation of homologous DNA sequences, thus achieving improved genotyping-by-sequencing efficiency. Our modifications facilitate generation of single-sample libraries, enabling individual genotype assignments instead of pooled-sample analysis. We sequenced ~1% of the orangutan genome with 41-fold median coverage in 31 wild-born individuals from two populations. SNPs and genotypes were called using three different algorithms. We obtained substantially different SNP datasets depending on the SNP caller. Genotype validations revealed that the Unified Genotyper of the Genome Analysis Toolkit and SAMtools performed significantly better than a caller from CLC Genomics Workbench (CLC). Of all conflicting genotype calls, CLC was only correct in 17% of the cases. Furthermore, conflicting genotypes between two algorithms showed a systematic bias in that one caller almost exclusively assigned heterozygotes, while the other one almost exclusively assigned homozygotes. CONCLUSIONS: Our enhanced iRRL approach greatly facilitates genotyping-by-sequencing and thus direct estimates of allele frequencies. Our direct comparison of three commonly used SNP callers emphasizes the need to question the accuracy of SNP and genotype calling, as we obtained considerably different SNP datasets depending on caller algorithms, sequencing depths and filtering criteria. These differences affected scans for signatures of natural selection, but will also exert undue influences on demographic inferences. This study presents the first effort to generate a population genomic dataset for wild-born orangutans with known population provenance.
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Algoritmos , Bases de Dados Genéticas , Genoma , Genômica/métodos , Polimorfismo de Nucleotídeo Único , Pongo abelii/genética , Animais , Biologia Computacional , Frequência do Gene , Genótipo , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , SoftwareRESUMO
BACKGROUND: Clinical trials of radiation after radical cystectomy (RC) and chemotherapy for bladder cancer are in development, but inclusion and stratification factors have not been clearly established. In this study, the authors evaluated and refined a published risk stratification for locoregional failure (LF) by applying it to a multicenter patient cohort. METHODS: The original stratification, which was developed using a single-institution series, produced 3 subgroups with significantly different LF risk based on pathologic tumor (pT) classification and the number of lymph nodes identified. This model was then applied to patients in Southwest Oncology Group (SWOG) 8710, a randomized trial of RC with or without chemotherapy. LF was defined as any pelvic failure before or within 3 months of distant failure. RESULTS: Patients in the development cohort and the SWOG cohort had significantly different baseline characteristics. The original risk model was not fully validated in the SWOG cohort, because lymph node yield was not as strongly associated with LF as in the development cohort. Regression analysis indicated that margin status could improve the model. A revised stratification using pT classification, margin status, and the number of lymph nodes identified produced 3 subgroups with significantly different LF risk in both cohorts: low risk (≤pT2), intermediate risk (≥pT3 with negative margins AND ≥10 lymph nodes identified), and high risk (≥pT3 with positive margins OR <10 lymph nodes identified) with 5-year LF rates of 8%, 20%, and 41%, respectively, in the SWOG cohort and 8%, 19%, and 41%, respectively, in the development cohort. CONCLUSIONS: A model incorporating pT classification, margin status, and the number of lymph nodes identified stratified LF risk in 2 different RC populations and may inform the design of future trials.
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Cistectomia , Recidiva Local de Neoplasia/etiologia , Neoplasias da Bexiga Urinária/cirurgia , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Risco , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologiaRESUMO
Effective teamwork is not only essential for teams themselves, but also for organizations and our society. To facilitate team processes and enhance team performance, feedback interventions are a widely used means. However, different types of feedback (i.e., individual vs. team-level feedback, performance vs. process feedback) can have various effects leaving the question of their effectiveness unanswered. This is especially important when team members' attitudes (namely collective orientation) are considered. Thus, understanding the interplay between types of feedback and team members' attitudes would reveal new opportunities for fostering reliable teamwork. The methodology of the present study is based on a laboratory approach. Teams (N = 142) of two worked together over four scenarios to extinguish forest fires in a microworld. We examined the effects of collective orientation on team coordination and team performance. To understand the interplay between feedback and attitudes we examined the effect of different feedback interventions on team performance and on a change in collective orientation. For analyzing multilevel mediation and changes over time, Bayesian multilevel models were applied. Results show a positive relationship between collective orientation and team performance mediated by coordination. Additionally, team-level process and performance feedback seem to be slightly more beneficial for maintaining performance over time with increasing difficulty of the task compared to individual-level process feedback. Feedback can lead to an increase in collective orientation if these values are low at the beginning. Our research highlights the importance of collective orientation and feedback interventions on team processes and performance for interdependently working teams.
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Retroalimentação , Teorema de BayesRESUMO
Recent advances in population genomics have triggered great interest in the genomic landscape of divergence in taxa with 'porous' species boundaries. One important obstable of previous studies of this topic was the low genomic coverage achieved. This issue can now be overcome by the use of 'next generation' or short-read DNA-sequencing approaches capable of assaying many thousands of single nucleotide polymorphisms (SNPs) in divergent species. We have scanned the 'porous' genomes of Populus alba and Populus tremula, two ecologically divergent hybridizing forest trees, using >38,000 SNPs assayed by restriction site associated DNA (RAD) sequencing. Windowed analyses indicate great variation in genetic divergence (e.g. the proportion of fixed SNPs) between species, and these results are unlikely to be strongly biased by genomic features of the Populus trichocarpa reference genome used for SNP calling. Divergence estimates were significantly autocorrelated (P < 0.01; Moran's I up to 0.6) along 11 of 19 chromosomes. Many of these autocorrelations involved low divergence blocks, thus suggesting that allele sharing was caused by recurrent gene flow rather than shared ancestral polymorphism. A conspicuous low divergence block of three megabases was detected on chromosome XIX, recently put forward as an incipient sex chromosome in Populus, and was largely congruent with introgression of mapped microsatellites in two natural hybrid zones (N > 400). Our results help explain the origin of the 'genomic mosaic' seen in these taxa with 'porous' genomes and suggest rampant introgression or extensive among-species conservation of an incipient plant sex chromosome. RAD sequencing holds great promise for detecting patterns of divergence and gene flow in highly divergent hybridizing species.
Assuntos
Fluxo Gênico , Genômica/métodos , Polimorfismo de Nucleotídeo Único , Populus/genética , Cromossomos de Plantas , DNA de Plantas/genética , Genoma de Planta , Hibridização Genética , Repetições de Microssatélites , Populus/classificação , Análise de Sequência de DNARESUMO
Described is a novel organorhodium(I) complex that is cytotoxic to the colon cancer cell line HCT116 and alters cell migration, DNA replication, and DNA condensation. Most importantly, the mechanism observed is not seen for the parent organorhodium dimer complex [{RhCl(COD)}2], RhCl3, or the free ligand/proligands (COD and 1-(n)butyl-3-methylimidazolium chloride). Thus, the activity of this organorhodium complex is attributable to its unique structure.