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1.
Psychol Health ; : 1-16, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36134694

RESUMO

OBJECTIVE: Fibromyalgia (FM) is a chronic pain condition often accompanied by sleep problems and depression that are each associated with reduced physical ability including postural control. Research supports a sequential association between pain intensity and depression in FM, and poor sleep quality may play a key role in this relationship. This study aimed to verify a serial pattern of associations among sleep quality, pain intensity, and depressive symptoms and quantify these effects on objective postural control. DESIGN: Community-residing adults diagnosed with FM (n = 155; Mage = 61.08, SD = 7.70; 93% female; 79% White) were included in this cross-sectional study. MAIN OUTCOMES: Participants self-rated sleep quality (restorative sleep, sleep waking, and sleep latency), pain intensity, and depressive symptoms, and the Fullerton Advanced Balance (FAB) scale and 8-Foot Up and Go Test (8FUPGT) measured objective postural control. RESULTS: Findings indicated that the serial association between pain intensity and depressive symptoms fully mediated the relationship between sleep quality and both FAB (95% CI [-.125, -.013]), and 8FUPGT (95% CI [.002, .033]) performance. CONCLUSION: Findings highlight the serial association of pain intensity and depressive symptoms with objective postural control performance and the potential for sleep and depression interventions that may maximize functional outcomes in FM.

2.
Proc Natl Acad Sci U S A ; 119(30): e2201285119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35867817

RESUMO

Although complex interactions between hosts and microbial associates are increasingly well documented, we still know little about how and why hosts shape microbial communities in nature. In addition, host genetic effects on microbial communities vary widely depending on the environment, obscuring conclusions about which microbes are impacted and which plant functions are important. We characterized the leaf microbiota of 200 Arabidopsis thaliana genotypes in eight field experiments and detected consistent host effects on specific, broadly distributed microbial species (operational taxonomic unit [OTUs]). Host genetic effects disproportionately influenced central ecological hubs, with heritability of particular OTUs declining with their distance from the nearest hub within the microbial network. These host effects could reflect either OTUs preferentially associating with specific genotypes or differential microbial success within them. Host genetics associated with microbial hubs explained over 10% of the variation in lifetime seed production among host genotypes across sites and years. We successfully cultured one of these microbial hubs and demonstrated its growth-promoting effects on plants in sterile conditions. Finally, genome-wide association mapping identified many putatively causal genes with small effects on the relative abundance of microbial hubs across sites and years, and these genes were enriched for those involved in the synthesis of specialized metabolites, auxins, and the immune system. Using untargeted metabolomics, we corroborate the consistent association between variation in specialized metabolites and microbial hubs across field sites. Together, our results reveal that host genetic variation impacts the microbial communities in consistent ways across environments and that these effects contribute to fitness variation among host genotypes.


Assuntos
Arabidopsis , Interações entre Hospedeiro e Microrganismos , Microbiota , Folhas de Planta , Arabidopsis/genética , Arabidopsis/microbiologia , Estudo de Associação Genômica Ampla , Interações entre Hospedeiro e Microrganismos/genética , Folhas de Planta/genética , Folhas de Planta/microbiologia
3.
Philos Trans R Soc Lond B Biol Sci ; 377(1855): 20200512, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35634919

RESUMO

A paradoxical finding from genome-wide association studies (GWAS) in plants is that variation in metabolite profiles typically maps to a small number of loci, despite the complexity of underlying biosynthetic pathways. This discrepancy may partially arise from limitations presented by geographically diverse mapping panels. Properties of metabolic pathways that impede GWAS by diluting the additive effect of a causal variant, such as allelic and genetic heterogeneity and epistasis, would be expected to increase in severity with the geographical range of the mapping panel. We hypothesized that a population from a single locality would reveal an expanded set of associated loci. We tested this in a French Arabidopsis thaliana population (less than 1 km transect) by profiling and conducting GWAS for glucosinolates, a suite of defensive metabolites that have been studied in depth through functional and genetic mapping approaches. For two distinct classes of glucosinolates, we discovered more associations at biosynthetic loci than the previous GWAS with continental-scale mapping panels. Candidate genes underlying novel associations were supported by concordance between their observed effects in the TOU-A population and previous functional genetic and biochemical characterization. Local populations complement geographically diverse mapping panels to reveal a more complete genetic architecture for metabolic traits. This article is part of the theme issue 'Genetic basis of adaptation and speciation: from loci to causative mutations'.


Assuntos
Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Variação Genética , Estudo de Associação Genômica Ampla , Glucosinolatos/metabolismo , Locos de Características Quantitativas
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 3322-3327, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891951

RESUMO

Ultrasound scanning is essential in several medical diagnostic and therapeutic applications. It is used to visualize and analyze anatomical features and structures that influence treatment plans. However, it is both labor intensive, and its effectiveness is operator dependent. Real-time accurate and robust automatic detection and tracking of anatomical structures while scanning would significantly impact diagnostic and therapeutic procedures to be consistent and efficient. In this paper, we propose a deep learning framework to automatically detect and track a specific anatomical target structure in ultrasound scans. Our framework is designed to be accurate and robust across subjects and imaging devices, to operate in real-time, and to not require a large training set. It maintains a localization precision and recall higher than 90% when trained on training sets that are as small as 20% in size of the original training set. The framework backbone is a weakly trained segmentation neural network based on U-Net. We tested the framework on two different ultrasound datasets with the aim to detect and track the Vagus nerve, where it outperformed current state-of-the-art real-time object detection networks.Clinical Relevance-The proposed approach provides an accurate method to detect and localize target anatomical structures in real-time, assisting sonographers during ultrasound scanning sessions by reducing diagnostic and detection errors, and expediting the duration of scanning sessions.


Assuntos
Redes Neurais de Computação , Humanos , Ultrassonografia , Nervo Vago
5.
J Vasc Surg ; 71(4): 1378-1389.e3, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32035769

RESUMO

BACKGROUND: Neointimal hyperplasia is a major contributor to restenosis after arterial interventions, but the genetic and environmental mechanisms underlying the variable propensity for neointimal hyperplasia between individuals, including the role of commensal microbiota, are not well understood. We sought to characterize how shifting the microbiome using cage sharing and bedding mixing between rats with differing restenosis phenotypes after carotid artery balloon angioplasty could alter arterial remodeling. METHODS: We co-housed and mixed bedding between genetically distinct rats (Lewis [LE] and Sprague-Dawley [SD]) that harbor different commensal microbes and that are known to have different neointimal hyperplasia responses to carotid artery balloon angioplasty. Sequencing of the 16S ribosomal RNA gene was used to monitor changes in the gut microbiome. RESULTS: There were significant differences in neointimal hyperplasia between non-co-housed LE and SD rats 14 days after carotid artery angioplasty (mean intima + media [I + M] area, 0.117 ± 0.014 mm2 LE vs 0.275 ± 0.021 mm2 SD; P < .001) that were diminished by co-housing. Co-housing also altered local adventitial Ki67 immunoreactivity, local accumulation of leukocytes and macrophages (total and M2), and interleukin 17A concentration 3 days after surgery in each strain. Non-co-housed SD and LE rats had microbiomes distinguished by both weighted (P = .012) and unweighted (P < .001) UniFrac beta diversity distances, although without significant differences in alpha diversity. The difference in unweighted beta diversity between the fecal microbiota of SD and LE rats was significantly reduced by co-housing. Operational taxonomic units that significantly correlated with average I + M area include Parabacteroides distasonis, Desulfovibrio, Methanosphaera, Peptococcus, and Prevotella. Finally, serum concentrations of microbe-derived metabolites hydroxyanthranilic acid and kynurenine/tryptophan ratio were significantly associated with I + M area in both rat strains independent of co-housing. CONCLUSIONS: We describe a novel mechanism for how microbiome manipulations affect arterial remodeling and the inflammatory response after arterial injury. A greater understanding of the host inflammatory-microbe axis could uncover novel therapeutic targets for the prevention and treatment of restenosis.


Assuntos
Angioplastia com Balão , Lesões das Artérias Carótidas/patologia , Microbioma Gastrointestinal , Inflamação/patologia , Neointima/patologia , Animais , Fezes/microbiologia , Hiperplasia , Ratos , Ratos Endogâmicos Lew , Ratos Sprague-Dawley
6.
Oecologia ; 186(4): 895-906, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29480452

RESUMO

Differences among individuals within species affect community and ecosystem processes in many systems, and may rival the importance of differences between species. Intraspecific variation consists of both plastic and genetic components that are regulated by different processes and operate on different time scales. Therefore, probing which mechanisms can affect traits sufficiently strongly to affect ecosystem processes is fundamental to understanding the consequences of individual variation. We find that a dominant deciduous tree of Pacific Northwest riparian ecosystems, red alder, exhibits strong and synergistic responses to nutrient resources and herbivory stress. These induced responses, which include shifting nutrient and plant secondary metabolite composition, have cascading effects on aquatic ecosystem function. Defense responses suppress leaf litter decomposition in small streams, thus altering the rate of energy capture for one of the most abundant terrestrial carbon sources entering aquatic systems. We find that alder responses to herbivory stress largely depend on availability of soil nutrients, with modification of the highly cytotoxic diarylheptanoid group of secondary metabolites being favored in nutrient-poor environments and modification of the typically dose-dependent ellagitannins being favored in nutrient-rich environments. Importantly, these findings identify traits for herbivore resistance in alder trees and demonstrate that plastic responses occurring within a species and over short time scales substantially alter a key function of an adjacent ecosystem. Furthermore, demonstrating plasticity among alder secondary metabolites lends insight into this system, in which decomposer communities are known to adjust to the secondary chemistry of local alder trees to facilitate rapid decomposition of locally derived leaf litter.


Assuntos
Ecossistema , Plantas , Adaptação Fisiológica , Noroeste dos Estados Unidos , Folhas de Planta , Árvores
7.
Astrophys J Suppl Ser ; 235(2)2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32908325

RESUMO

We present the Kepler Object of Interest (KOI) catalog of transiting exoplanets based on searching four years of Kepler time series photometry (Data Release 25, Q1-Q17). The catalog contains 8054 KOIs of which 4034 are planet candidates with periods between 0.25 and 632 days. Of these candidates, 219 are new in this catalog and include two new candidates in multi-planet systems (KOI-82.06 and KOI-2926.05), and ten new high-reliability, terrestrial-size, habitable zone candidates. This catalog was created using a tool called the Robovetter which automatically vets the DR25 Threshold Crossing Events (TCEs) found by the Kepler Pipeline (Twicken et al. 2016). Because of this automation, we were also able to vet simulated data sets and therefore measure how well the Robovetter separates those TCEs caused by noise from those caused by low signal-to-noise transits. Because of these measurements we fully expect that this catalog can be used to accurately calculate the frequency of planets out to Kepler's detection limit, which includes temperate, super-Earth size planets around GK dwarf stars in our Galaxy. This paper discusses the Robovetter and the metrics it uses to decide which TCEs are called planet candidates in the DR25 KOI catalog. We also discuss the simulated transits, simulated systematic noise, and simulated astrophysical false positives created in order to characterize the properties of the final catalog. For orbital periods less than 100 d the Robovetter completeness (the fraction of simulated transits that are determined to be planet candidates) across all observed stars is greater than 85%. For the same period range, the catalog reliability (the fraction of candidates that are not due to instrumental or stellar noise) is greater than 98%. However, for low signal-to-noise candidates found between 200 and 500 days, our measurements indicate that the Robovetter is 73.5% complete and 37.2% reliable across all searched stars (or 76.7% complete and 50.5% reliable when considering just the FGK dwarf stars). We describe how the measured completeness and reliability varies with period, signal-to-noise, number of transits, and stellar type. Also, we discuss a value called the disposition score which provides an easy way to select a more reliable, albeit less complete, sample of candidates. The entire KOI catalog, the transit fits using Markov chain Monte Carlo methods, and all of the simulated data used to characterize this catalog are available at the NASA Exoplanet Archive.

8.
Ecology ; 97(8): 2125-2135, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27859211

RESUMO

Resource patchiness influences consumer foraging, movement, and physiology. Fluxes across ecosystem boundaries can extend these effects to otherwise distinct food webs. Intraspecific diversity of these cross-ecosystem subsidies can have large consequences for recipient systems. Here, we show intraspecific variation in leaf defensive chemistry of riparian trees drives local adaptation among terrestrial and riverine decomposers that consume shed leaf litter. We found extensive geographic structuring of ellagitannins, diarylheptanoids, and flavonoids in red alder trees. Ellagitannins, particularly those with strong oxidative activity, drive aquatic leaf decomposition. Further, spatial variation in these leaf components drives local ecological matching: in experiments using artificial food sources distinguished only by the chemical content of individual trees, we found decomposers both on land and in rivers more quickly consumed locally derived food sources. These results illustrate that terrestrial processes can change the chemistry of cross-ecosystem subsidies in ways that ultimately alter ecosystem function in donor and recipient systems.


Assuntos
Ecossistema , Cadeia Alimentar , Folhas de Planta/química , Ecologia , Folhas de Planta/fisiologia , Rios , Árvores
9.
Am J Physiol Gastrointest Liver Physiol ; 311(2): G286-304, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27340128

RESUMO

The metabolic benefits induced by gastric bypass, currently the most effective treatment for morbid obesity, are associated with bile acid (BA) delivery to the distal intestine. However, mechanistic insights into BA signaling in the mediation of metabolic benefits remain an area of study. The bile diversion () mouse model, in which the gallbladder is anastomosed to the distal jejunum, was used to test the specific role of BA in the regulation of glucose and lipid homeostasis. Metabolic phenotype, including body weight and composition, glucose tolerance, energy expenditure, thermogenesis genes, total BA and BA composition in the circulation and portal vein, and gut microbiota were examined. BD improves the metabolic phenotype, which is in accord with increased circulating primary BAs and regulation of enterohormones. BD-induced hypertrophy of the proximal intestine in the absence of BA was reversed by BA oral gavage, but without influencing BD metabolic benefits. BD-enhanced energy expenditure was associated with elevated TGR5, D2, and thermogenic genes, including UCP1, PRDM16, PGC-1α, PGC-1ß, and PDGFRα in epididymal white adipose tissue (WAT) and inguinal WAT, but not in brown adipose tissue. BD resulted in an altered gut microbiota profile (i.e., Firmicutes bacteria were decreased, Bacteroidetes were increased, and Akkermansia was positively correlated with higher levels of circulating primary BAs). Our study demonstrates that enhancement of BA signaling regulates glucose and lipid homeostasis, promotes thermogenesis, and modulates the gut microbiota, which collectively resulted in an improved metabolic phenotype.


Assuntos
Tecido Adiposo/metabolismo , Ácidos e Sais Biliares/sangue , Dieta Hiperlipídica , Metabolismo Energético , Jejuno/metabolismo , Obesidade/sangue , Adipocinas/sangue , Tecido Adiposo/fisiopatologia , Adiposidade , Animais , Glicemia/metabolismo , Modelos Animais de Doenças , Hormônios Gastrointestinais/sangue , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Jejuno/microbiologia , Jejuno/fisiopatologia , Lipídeos/sangue , Masculino , Camundongos Endogâmicos C57BL , Obesidade/microbiologia , Obesidade/fisiopatologia , Obesidade/cirurgia , Fenótipo , Transdução de Sinais , Termogênese
10.
Proc Natl Acad Sci U S A ; 112(13): 4032-7, 2015 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-25775585

RESUMO

The "mustard oil bomb" is a major defense mechanism in the Brassicaceae, which includes crops such as canola and the model plant Arabidopsis thaliana. These plants produce and store blends of amino acid-derived secondary metabolites called glucosinolates. Upon tissue rupture by natural enemies, the myrosinase enzyme hydrolyses glucosinolates, releasing defense molecules. Brassicaceae display extensive variation in the mixture of glucosinolates that they produce. To investigate the genetics underlying natural variation in glucosinolate profiles, we conducted a large genome-wide association study of 22 methionine-derived glucosinolates using A. thaliana accessions from across Europe. We found that 36% of among accession variation in overall glucosinolate profile was explained by genetic differentiation at only three known loci from the glucosinolate pathway. Glucosinolate-related SNPs were up to 490-fold enriched in the extreme tail of the genome-wide [Formula: see text] scan, indicating strong selection on loci controlling this pathway. Glucosinolate profiles displayed a striking longitudinal gradient with alkenyl and hydroxyalkenyl glucosinolates enriched in the West. We detected a significant contribution of glucosinolate loci toward general herbivore resistance and lifetime fitness in common garden experiments conducted in France, where accessions are enriched in hydroxyalkenyls. In addition to demonstrating the adaptive value of glucosinolate profile variation, we also detected long-distance linkage disequilibrium at two underlying loci, GS-OH and GS-ELONG. Locally cooccurring alleles at these loci display epistatic effects on herbivore resistance and fitness in ecologically realistic conditions. Together, our results suggest that natural selection has favored a locally adaptive configuration of physically unlinked loci in Western Europe.


Assuntos
Arabidopsis/química , Glucosinolatos/química , Herbivoria , Seleção Genética , Alelos , Animais , Arabidopsis/genética , Biodiversidade , Cromatografia Líquida , Epistasia Genética , Evolução Molecular , Genômica , Genótipo , Geografia , Insetos , Desequilíbrio de Ligação , Metionina/química , Polimorfismo de Nucleotídeo Único , Análise de Componente Principal , Locos de Características Quantitativas , Espectrometria de Massas em Tandem
11.
J Vis Exp ; (72)2013 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-23426078

RESUMO

The angular resolution of ground-based optical telescopes is limited by the degrading effects of the turbulent atmosphere. In the absence of an atmosphere, the angular resolution of a typical telescope is limited only by diffraction, i.e., the wavelength of interest, λ, divided by the size of its primary mirror's aperture, D. For example, the Hubble Space Telescope (HST), with a 2.4-m primary mirror, has an angular resolution at visible wavelengths of ~0.04 arc seconds. The atmosphere is composed of air at slightly different temperatures, and therefore different indices of refraction, constantly mixing. Light waves are bent as they pass through the inhomogeneous atmosphere. When a telescope on the ground focuses these light waves, instantaneous images appear fragmented, changing as a function of time. As a result, long-exposure images acquired using ground-based telescopes--even telescopes with four times the diameter of HST--appear blurry and have an angular resolution of roughly 0.5 to 1.5 arc seconds at best. Astronomical adaptive-optics systems compensate for the effects of atmospheric turbulence. First, the shape of the incoming non-planar wave is determined using measurements of a nearby bright star by a wavefront sensor. Next, an element in the optical system, such as a deformable mirror, is commanded to correct the shape of the incoming light wave. Additional corrections are made at a rate sufficient to keep up with the dynamically changing atmosphere through which the telescope looks, ultimately producing diffraction-limited images. The fidelity of the wavefront sensor measurement is based upon how well the incoming light is spatially and temporally sampled. Finer sampling requires brighter reference objects. While the brightest stars can serve as reference objects for imaging targets from several to tens of arc seconds away in the best conditions, most interesting astronomical targets do not have sufficiently bright stars nearby. One solution is to focus a high-power laser beam in the direction of the astronomical target to create an artificial reference of known shape, also known as a 'laser guide star'. The Robo-AO laser adaptive optics system, employs a 10-W ultraviolet laser focused at a distance of 10 km to generate a laser guide star. Wavefront sensor measurements of the laser guide star drive the adaptive optics correction resulting in diffraction-limited images that have an angular resolution of ~0.1 arc seconds on a 1.5-m telescope.


Assuntos
Astronomia/instrumentação , Óptica e Fotônica/instrumentação , Telescópios , Fenômenos Astronômicos , Astronomia/métodos , Raios Infravermelhos , Lasers , Óptica e Fotônica/métodos , Raios Ultravioleta
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