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https://www.readbyqxmd.com/read/28539032/elevated-gastric-antrum-erosions-in-portal-hypertension-patients-peptic-disease-or-mucosal-congestion
#1
Fernanda Cordeiro de Azevedo Conejo, Mabel Tatty Medeiros Fracassi, Maurício Saab Assef, Maurício Alves Ribeiro, Luiz Arnaldo Szutan, Fabio Gonçalves Ferreira
Background/Aims: Portal hypertension (PH) is a syndrome characterized by chronic increase in the pressure gradient between the portal vein and inferior vena cava. Previous studies have suggested an increased frequency of antral elevated erosive gastritis in patients with PH, as well as an etiologic association; however, there has not been any histological evidence of this hypothesis to date. Our aim was to evaluate the histological features found in elevated antral erosions in patients with portal hypertension...
May 25, 2017: Korean Journal of Gastroenterology, Taehan Sohwagi Hakhoe Chi
https://www.readbyqxmd.com/read/28538397/quality-of-reporting-of-multivariable-logistic-regression-models-in-chinese-clinical-medical-journals
#2
Ying-Ying Zhang, Xiao-Bin Zhou, Qiu-Zhen Wang, Xiao-Yan Zhu
Multivariable logistic regression (MLR) has been increasingly used in Chinese clinical medical research during the past few years. However, few evaluations of the quality of the reporting strategies in these studies are available.To evaluate the reporting quality and model accuracy of MLR used in published work, and related advice for authors, readers, reviewers, and editors.A total of 316 articles published in 5 leading Chinese clinical medical journals with high impact factor from January 2010 to July 2015 were selected for evaluation...
May 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28538203/uhplc-ms-ms-method-with-sample-dilution-to-test-therapeutic-adherence-through-quantification-of-ten-antihypertensive-drugs-in-urine-samples
#3
Amedeo De Nicolò, Valeria Avataneo, Franco Rabbia, Mauro Sciandra, Francesco Tosello, Jessica Cusato, Elisa Perlo, Paolo Mulatero, Franco Veglio, Giovanni Di Perri, Antonio D'Avolio
Nowadays, hypertension represents an important health problem, particularly in developed countries. In some cases the standard therapeutic approaches are not able to reestablish the normal blood pressure values: this condition is called "resistant hypertension". However, a fraction of cases of resistant hypertension are actually due to poor adherence to the prescribed therapy. Therapeutic Drug Monitoring could represent a direct and useful tool to correctly identify non-compliant patients. Nevertheless, high throughput methods for the simultaneous monitoring of a wide panel of drugs in the same analysis are lacking and, furthermore, there is not a generally acknowledged "standard" matrix for this test (plasma or urine)...
May 13, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28538159/long-term-stochastic-editing-of-regenerative-anatomy-via-targeting-endogenous-bioelectric-gradients
#4
Fallon Durant, Junji Morokuma, Christopher Fields, Katherine Williams, Dany Spencer Adams, Michael Levin
We show that regenerating planarians' normal anterior-posterior pattern can be permanently rewritten by a brief perturbation of endogenous bioelectrical networks. Temporary modulation of regenerative bioelectric dynamics in amputated trunk fragments of planaria stochastically results in a constant ratio of regenerates with two heads to regenerates with normal morphology. Remarkably, this is shown to be due not to partial penetrance of treatment, but a profound yet hidden alteration to the animals' patterning circuitry...
May 23, 2017: Biophysical Journal
https://www.readbyqxmd.com/read/28538023/magnetic-resonance-imaging-based-assessment-of-breast-cancer-related-lymphoedema-tissue-composition
#5
Marco Borri, Kristiana D Gordon, Julie C Hughes, Erica D Scurr, Dow-Mu Koh, Martin O Leach, Peter S Mortimer, Maria A Schmidt
OBJECTIVES: The aim of this study was to propose a magnetic resonance imaging acquisition and analysis protocol that uses image segmentation to measure and depict fluid, fat, and muscle volumes in breast cancer-related lymphoedema (BCRL). This study also aims to compare affected and control (unaffected) arms of patients with diagnosed BCRL, providing an analysis of both the volume and the distribution of the different tissue components. MATERIALS AND METHODS: The entire arm was imaged with a fluid-sensitive STIR and a 2-point 3-dimensional T1W gradient-echo-based Dixon sequences, acquired in sagittal orientation and covering the same imaging volume...
May 19, 2017: Investigative Radiology
https://www.readbyqxmd.com/read/28535597/variation-and-accumulation-patterns-of-poly-and-perfluoroalkyl-substances-pfas-in-european-perch-perca-fluviatilis-across-a-gradient-of-pristine-swedish-lakes
#6
Staffan Åkerblom, Nesrin Negm, Pianpian Wu, Kevin Bishop, Lutz Ahrens
This study assessed variations in the concentrations of poly- and perfluoroalkyl substances (PFAS) in European perch (Perca fluviatilis) in Swedish lakes and the extent to which fish size, age and indicators of fish trophic ecology (δ(15)N and δ(13)C) correlate with the sum of individual PFAS concentrations (ΣPFAS). Fish muscle tissue samples (n=80) were taken from six lakes across Sweden and analysed using solid-liquid extraction followed by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS)...
May 19, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28535463/atmospheric-concentrations-distributions-and-air-soil-exchange-tendencies-of-pahs-and-pcbs-in-a-heavily-industrialized-area-in-kocaeli-turkey
#7
Banu Cetin, Sema Yurdakul, Melek Keles, Isil Celik, Fatma Ozturk, Cevdet Dogan
Dilovasi is one of the heavily industrialized areas in Turkey with serious environmental problems. In this study, the atmospheric concentration of PAHs and PCBs were measured for a whole year at 23 sites. The average ambient air Σ15PAH and Σ41PCB concentrations were found as 285 ± 431 ng m(-3) and 4152 ± 6072 pg m(-3), respectively. PAH concentrations increased with decreasing temperature especially in urban areas, indicating the impact of residential heating. However, PCB concentrations mostly increased with temperature probably due to enhanced volatilization from their sources...
May 19, 2017: Chemosphere
https://www.readbyqxmd.com/read/28535452/highly-sensitive-uhplc-ms-ms-method-for-the-simultaneous-estimation-of-propafenone-and-its-metabolites-5-hydroxypropafenone-and-n-depropylpropafenone-on-human-dried-blood-spots-technique-and-application-to-a-pharmacokinetic-study
#8
Adinarayana Andy, Raja Reddy Kallem, Ramesh Mullangi, Divya Andy, J V L N Seshagiri Rao
A highly sensitive, rapid and selective UHPLC-MS/MS method has been developed and validated for quantification of the propafenone (PF), 5-hydroxypropafenone (5-OHPF) and N-depropylpropafenone (N-DPF) on human dried blood spot (DBS). The assay procedure involves a solid-liquid extraction of PF, 5-OHPF and N-DPF and amlodipine (internal standard, I.S.) from dried human DBS cards using water and acetonitrile. The chromatographic resolution was achieved on a BEH C18 column using a gradient mobile phase consisting of 0...
May 11, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28535356/one-dimensional-carrier-confinement-in-giant-cds-cdse-excitonic-nanoshells
#9
Natalia Razgoniaeva, Pavel Moroz, Mingrui Yang, Darya S Budkina, Holly Eckard, Marissa Augspurger, Dmitriy Khon, Alexander N Tarnovsky, Mikhail Zamkov
The emerging generation of quantum dot optoelectronic devices offers an appealing prospect of a size-tunable band gap. The confinement-enabled control over electronic properties, however, requires nanoparticles to be sufficiently small, which leads to a large area of inter-particle boundaries in a film. Such interfaces lead to a high density of surface traps which ultimately increase the electrical resistance of a solid. To address this issue, we have developed an inverse energy-gradient core/shell architecture supporting the quantum confinement in nanoparticles larger than the exciton Bohr radius...
May 23, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28535352/a-hierarchical-phosphorus-nanobarbed-nanowire-hybrid%C3%AF-its-structure-and-electrochemical-properties
#10
Dan Zhao, Beibei Li, Jinying Zhang, Xin Li, Dingbin Xiao, Chengcheng Fu, Lihui Zhang, Zhihui Li, Jun Li, Daxian Cao, Chunming Niu
Nanostructured phosphorus-carbon composites are promising materials for Li-ion and Na-ion battery anodes. A hierarchical phosphorus hybrid, SiC@graphene@P, has been synthesized by chemical vapor deposition of phosphorous on the surfaces of barbed nanowires, where the barbs are vertically grown graphene nanosheets and the cores are SiC nanowires. A temperature gradient vaporization-condensation method has been used to remove the unhybridized phosphorous particles formed by homogeneous nucleation. The vertically grown barb shaped graphene nanosheets and high concentration of edge carbon atoms induced a fibrous red phosphorus (f-RP) growth with its {001} planes in parallel to {002} planes of nanographene sheets and led to a strong interpenetrated interface interaction between phosphorous and the surfaces of graphene nanosheets...
May 23, 2017: Nano Letters
https://www.readbyqxmd.com/read/28535168/invited-commentary-evolution-of-social-networks-health-and-the-role-of-epidemiology
#11
Allison E Aiello
Almost 40 years ago, Berkman and Syme demonstrated that social networks were related to the risk of early mortality (Am J Epidemiol. 1979;109(2):186-204). Their study was highly innovative because they directly measured and quantified social networks in a large prospective population-based survey with mortality follow-up. The results of the study showed robust network gradients, whereby those with fewer networks and weaker social ties had significantly higher mortality rates. The important influence of social networks that Berkman and Syme noted many years ago is likely to heighten in the future, as demographic characteristics shift and individuals become more inclined to socialize through online platforms instead of real-world interactions...
May 23, 2017: American Journal of Epidemiology
https://www.readbyqxmd.com/read/28535166/adult-height-prevalent-coronary-calcium-score-and-incident-cardiovascular-outcomes-in-a-multi-ethnic-cohort
#12
Joseph Yeboah, Michael J Blaha, Erin D Michos, Waqas Qureshi, Michael Miedema, Peter Flueckiger, Carlos J Rodriguez, Moyses Szklo, Alain G Bertoni
We assessed the relationships among adult height, coronary artery calcium (CAC) scores, incident atherosclerotic cardiovascular disease (ASCVD) events, and atrial fibrillation (Afib) in a multi-ethnic cohort. We used race/ethnicity -specific height (dichotomized by median and quartiles) as the predictor variable within the four race/ethnic groups in the Multi-Ethnic Study of Atherosclerosis (N = 6,814). After a mean of 10.2 years of follow-up (2000-2012), 556 ASCVD events (8.2%) and 539 afib events (7.9%) occurred...
May 23, 2017: American Journal of Epidemiology
https://www.readbyqxmd.com/read/28534960/cellular-na-handling-mechanisms-involved-in-airway-smooth-muscle-contraction-review
#13
Bettina Sommer, Edgar Flores-Soto, Georgina Gonzalez-Avila
A decrease in bronchial diameter is designated as bronchoconstriction (BC) and impedes the flow of air through the airway. Asthma is characterized by inflammation of the airways, reversible BC and nonspecific hyperreactivity. These last two symptoms are dependent on airway smooth muscle. Stimuli that trigger contraction can be characterized as chemical (neurotransmitters, cytokines and terpenoids) and physical (volume inspired, air pressure). Both stimuli activate signaling pathways by acting on membrane proteins and facilitating the passage of ions through the membrane, generating a voltage change and a subsequent depolarization...
May 17, 2017: International Journal of Molecular Medicine
https://www.readbyqxmd.com/read/28534911/cellular-orientation-is-guided-by-strain-gradients
#14
Sophie Chagnon-Lessard, Hubert Jean-Ruel, Michel Godin, Andrew E Pelling
The strain-induced reorientation response of cyclically stretched cells has been well characterized in uniform strain fields. In the present study, we comprehensively analyse the behaviour of human fibroblasts subjected to a highly non-uniform strain field within a polymethylsiloxane microdevice. Our results indicate that the strain gradient amplitude and direction regulate cell reorientation through a coordinated gradient avoidance response. We provide critical evidence that strain gradient is a key physical cue that can guide cell organization...
May 23, 2017: Integrative Biology: Quantitative Biosciences From Nano to Macro
https://www.readbyqxmd.com/read/28534901/realisation-and-optical-engineering-of-linear-variable-bandpass-filters-in-nanoporous-anodic-alumina-photonic-crystals
#15
Sukarno, Cheryl Suwen Law, Abel Santos
We present the first realisation of linear variable bandpass filters in nanoporous anodic alumina (NAA-LVBPFs) photonic crystal structures. NAA gradient-index filters (NAA-GIFs) are produced by sinusoidal pulse anodisation and used as photonic crystal platforms to generate NAA-LVBPFs. The anodisation period of NAA-GIFs is modified from 650 to 850 s to systematically tune the characteristic photonic stopband of these photonic crystals across the UV-visible-NIR spectrum. Then, the nanoporous structure of NAA-GIFs is gradually widened along the surface under controlled conditions by wet chemical etching using a dip coating approach aiming to create NAA-LVBPFs with finely engineered optical properties...
May 23, 2017: Nanoscale
https://www.readbyqxmd.com/read/28534879/epibionts-dominate-metabolic-functional-potential-of-trichodesmium-colonies-from-the-oligotrophic-ocean
#16
Kyle R Frischkorn, Mónica Rouco, Benjamin A S Van Mooy, Sonya T Dyhrman
Trichodesmium is a genus of marine diazotrophic colonial cyanobacteria that exerts a profound influence on global biogeochemistry, by injecting 'new' nitrogen into the low nutrient systems where it occurs. Colonies of Trichodesmium ubiquitously contain a diverse assemblage of epibiotic microorganisms, constituting a microbiome on the Trichodesmium host. Metagenome sequences from Trichodesmium colonies were analyzed along a resource gradient in the western North Atlantic to examine microbiome community structure, functional diversity and metabolic contributions to the holobiont...
May 23, 2017: ISME Journal
https://www.readbyqxmd.com/read/28534858/an-adaptive-orientation-estimation-method-for-magnetic-and-inertial-sensors-in-the-presence-of-magnetic-disturbances
#17
Bingfei Fan, Qingguo Li, Chao Wang, Tao Liu
Magnetic and inertial sensors have been widely used to estimate the orientation of human segments due to their low cost, compact size and light weight. However, the accuracy of the estimated orientation is easily affected by external factors, especially when the sensor is used in an environment with magnetic disturbances. In this paper, we propose an adaptive method to improve the accuracy of orientation estimations in the presence of magnetic disturbances. The method is based on existing gradient descent algorithms, and it is performed prior to sensor fusion algorithms...
May 19, 2017: Sensors
https://www.readbyqxmd.com/read/28534802/organ-location-determination-and-contour-sparse-representation-for-multi-organ-segmentation
#18
Siqi Li, Huiyan Jiang, Yu-Dong Yao, Benqiang Yang
Organ segmentation on computed tomography (CT) images is of great importance in medical diagnoses and treatment. This paper proposes organ location determination and contour sparse representation methods (OLD-CSR) for multiorgan segmentation (liver, kidney, and spleen) on abdomen CT images using an extreme learning machine (ELM) classifier. First, a location determination method is designed to obtain location information of each organ, which is used for coarse segmentation. Second, for coarse-to-fine segmentation, a contour gradient and rate change based feature point extraction method is proposed...
May 17, 2017: IEEE Journal of Biomedical and Health Informatics
https://www.readbyqxmd.com/read/28534790/neighborhood-based-stopping-criterion-for-contrastive-divergence
#19
Enrique Romero Merino, Ferran Mazzanti Castrillejo, Jordi Delgado Pin
Restricted Boltzmann Machines (RBMs) are general unsupervised learning devices to ascertain generative models of data distributions. RBMs are often trained using the Contrastive Divergence (CD) learning algorithm, an approximation to the gradient of the data log-likelihood (logL). A simple reconstruction error is often used as a stopping criterion for CD, although several authors have raised doubts concerning the feasibility of this procedure. In many cases, the evolution curve of the reconstruction error is monotonic, while the logL is not, thus indicating that the former is not a good estimator of the optimal stopping point for learning...
May 17, 2017: IEEE Transactions on Neural Networks and Learning Systems
https://www.readbyqxmd.com/read/28534494/airborne-observations-reveal-elevational-gradient-in-tropical-forest-isoprene-emissions
#20
Dasa Gu, Alex B Guenther, John E Shilling, Haofei Yu, Maoyi Huang, Chun Zhao, Qing Yang, Scot T Martin, Paulo Artaxo, Saewung Kim, Roger Seco, Trissevgeni Stavrakou, Karla M Longo, Julio Tóta, Rodrigo Augusto Ferreira de Souza, Oscar Vega, Ying Liu, Manish Shrivastava, Eliane G Alves, Fernando C Santos, Guoyong Leng, Zhiyuan Hu
Isoprene dominates global non-methane volatile organic compound emissions, and impacts tropospheric chemistry by influencing oxidants and aerosols. Isoprene emission rates vary over several orders of magnitude for different plants, and characterizing this immense biological chemodiversity is a challenge for estimating isoprene emission from tropical forests. Here we present the isoprene emission estimates from aircraft eddy covariance measurements over the Amazonian forest. We report isoprene emission rates that are three times higher than satellite top-down estimates and 35% higher than model predictions...
May 23, 2017: Nature Communications
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