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https://www.readbyqxmd.com/read/28922786/relapse-free-survival-as-a-surrogate-for-overall-survival-in-the-evaluation-of-stage-ii-iii-melanoma-adjuvant-therapy
#1
Stefan Suciu, Alexander M M Eggermont, Paul Lorigan, John M Kirkwood, Svetomir N Markovic, Claus Garbe, David Cameron, Srividya Kotapati, Tai-Tsang Chen, Keith Wheatley, Natalie Ives, Gaetan de Schaetzen, Achmad Efendi, Marc Buyse
Background: We assessed whether relapse-free survival (RFS; time until recurrence/death) is a valid surrogate for overall survival (OS) among resected stage II-III melanoma patients through a meta-analysis of randomized controlled trials. Methods: Individual patient data (IPD) on RFS and OS were collected from 5826 patients enrolled in 11 randomized adjuvant trials comparing interferon (IFN) to observation. In addition, IPD from two studies comparing IFN and vaccination in 989 patients were included...
January 1, 2018: Journal of the National Cancer Institute
https://www.readbyqxmd.com/read/28922123/a-data-driven-approach-for-furniture-and-indoor-scene-colorization
#2
Jie Zhu, Yanwen Guo, Han Ma
We present a data-driven approach that colorizes 3D furniture models and indoor scenes by leveraging indoor images on the internet. Our approach is able to colorize the furniture automatically according to an example image. The core is to learn image-guided mesh segmentation to segment the model into different parts according to the imaged object. Given an indoor scene, the system supports colorization-by-example, and has the ability to recommend the colorization scheme that is consistent with a user-desired color theme...
September 18, 2017: IEEE Transactions on Visualization and Computer Graphics
https://www.readbyqxmd.com/read/28920986/stratification-in-binary-colloidal-polymer-films-experiment-and-simulations
#3
D K Makepeace, A Fortini, A Markov, P Locatelli, C Lindsay, S Moorhouse, R Lind, R P Sear, J L Keddie
When films are deposited from mixtures of colloidal particles of two different sizes, a diverse range of functional structures can result. One structure of particular interest is a stratified film in which the top surface layer has a composition different than in the interior. Here, we explore the conditions under which a stratified layer of small particles develops spontaneously in a colloidal film that is cast from a binary mixture of small and large polymer particles that are suspended in water. A recent model, which considers the cross-interaction between the large and small particles (Zhou et al...
September 18, 2017: Soft Matter
https://www.readbyqxmd.com/read/28920931/single-molecule-fret-reveals-the-energy-landscape-of-the-full-length-sam-i-riboswitch
#4
Christoph Manz, Andrei Yu Kobitski, Ayan Samanta, Bettina G Keller, Andres Jäschke, G Ulrich Nienhaus
S-adenosyl-L-methionine (SAM) ligand binding induces major structural changes in SAM-I riboswitches, through which gene expression is regulated via transcription termination. Little is known about the conformations and motions governing the function of the full-length Bacillus subtilis yitJ SAM-I riboswitch. Therefore, we have explored its conformational energy landscape as a function of Mg(2+) and SAM ligand concentrations using single-molecule Förster resonance energy transfer (smFRET) microscopy and hidden Markov modeling analysis...
September 18, 2017: Nature Chemical Biology
https://www.readbyqxmd.com/read/28920713/estradiol-decreases-blood-pressure-in-association-with-redox-regulation-in-preeclampsia
#5
Goran M Babic, Snezana D Markovic, Mirjana Varjacic, Natasa Z Djordjevic, Tamara Nikolic, Isidora Stojic, Vladimir Jakovljevic
In this study, we tested a hypothesis that a short-term estradiol therapy may reduce blood pressure in preeclampsia by modulating plasma oxidative stress. The intramuscular injections of 10 mg 17-beta-estradiol were prescribed to preeclamptic pregnant women during the 3-day therapy before a labor induction. The analyses of mean arterial pressure (MAP), serum estradiol concentrations, plasma superoxide anion (O2.), hydrogen peroxide (H2O2), nitrites (NO2(-)), and peroxynitrite (ONOO(-)) were conducted before and during the therapy...
September 18, 2017: Clinical and Experimental Hypertension: CHE
https://www.readbyqxmd.com/read/28916284/stereotactic-body-radiotherapy-versus-low-dose-rate-brachytherapy-for-localised-prostate-cancer-a-cost-utility-analysis
#6
J Helou, S Torres, H B Musunuru, J Raphael, P Cheung, D Vesprini, H T Chung, L D'Alimonte, M Krahn, G Morton, A Loblaw
AIMS: To conduct a cost-utility analysis comparing stereotactic body radiotherapy (SBRT) with low dose rate brachytherapy (LDR-BT) for localised prostate cancer (PCa). MATERIALS AND METHODS: A decision-analytic Markov model was developed from the healthcare payer perspective to simulate the history of a 66-year-old man with low-risk PCa. The model followed patients yearly over their remaining lifetimes. Health states included 'recurrence-free', 'biochemical recurrence' (BR), 'metastatic' and 'death'...
September 12, 2017: Clinical Oncology: a Journal of the Royal College of Radiologists
https://www.readbyqxmd.com/read/28916180/interpreting-temporal-fluctuations-in-resting-state-functional-connectivity-mri
#7
REVIEW
Raphaël Liégeois, Timothy O Laumann, Abraham Z Snyder, Juan Zhou, B T Thomas Yeo
Resting-state functional connectivity is a powerful tool for studying human functional brain networks. Temporal fluctuations in functional connectivity, i.e., dynamic functional connectivity (dFC), are thought to reflect dynamic changes in brain organization and non-stationary switching of discrete brain states. However, recent studies have suggested that dFC might be attributed to sampling variability of static FC. Despite this controversy, a detailed exposition of stationarity and statistical testing of dFC is lacking in the literature...
September 12, 2017: NeuroImage
https://www.readbyqxmd.com/read/28915795/future-complications-of-chronic-hepatitis-c-in-a-low-risk-area-projections-from-the-hepatitis-c-study-in-northern-norway
#8
H Kileng, L Bernfort, T Gutteberg, O S Moen, M G Kristiansen, E J Paulssen, L K Berg, J Florholmen, R Goll
BACKGROUND: Hepatitis C (HCV) infection causes an asymptomatic chronic hepatitis in most affected individuals, which often remains undetected until cirrhosis and cirrhosis-related complications occur. Screening of high-risk subjects in Northern Norway has revealed a relatively low prevalence in the general population (0.24%). Despite this, late complications of HCV infection are increasing. Our object was to estimate the future prevalence and complications of chronic HCV infection in the period 2013-2050 in a low-risk area...
September 16, 2017: BMC Infectious Diseases
https://www.readbyqxmd.com/read/28915754/modeling-the-mechanism-of-cln025-beta-hairpin-formation
#9
Keri A McKiernan, Brooke E Husic, Vijay S Pande
Beta-hairpins are substructures found in proteins that can lend insight into more complex systems. Furthermore, the folding of beta-hairpins is a valuable test case for benchmarking experimental and theoretical methods. Here, we simulate the folding of CLN025, a miniprotein with a beta-hairpin structure, at its experimental melting temperature using a range of state-of-the-art protein force fields. We construct Markov state models in order to examine the thermodynamics, kinetics, mechanism, and rate-determining step of folding...
September 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28915306/cost-utility-study-of-warfarin-genotyping-in-the-vachs-affiliated-anticoagulation-clinic-of-puerto-rico
#10
Carlos Martes-Martinez, Cristian Méndez-Sepúlveda, Joel Millán-Molina, Matthew French-Kim, Heriberto Marín-Centeno, Giselle C Rivera-Miranda, José J Hernández-Muñoz, Jorge Duconge-Soler
OBJECTIVE: To evaluate the cost-utility of the pharmacogenetic-guided dosing of warfarin (PGx), when compared to the current dosing strategy. METHODS: A Markov model was developed to assess the impact of the genotypingguided warfarin dosing in a hypothetical cohort of patients. The model was based on the percentage of time patients spent within the therapeutic international normalized ratio (INR) range (PTTR). PTTR estimates and genotype distribution were derived from a cohort of patients (n = 206) treated in the Veteran Affairs Caribbean Healthcare System (VACHS) and from results of other research study...
September 2017: Puerto Rico Health Sciences Journal
https://www.readbyqxmd.com/read/28910782/spectral-analysis-of-epidemic-thresholds-of-temporal-networks
#11
Yi-Qing Zhang, Xiang Li, Athanasios V Vasilakos
Many complex systems can be modeled as temporal networks with time-evolving connections. The influence of their characteristics on epidemic spreading is analyzed in a susceptible-infected-susceptible epidemic model illustrated by the discrete-time Markov chain approach. We develop the analytical epidemic thresholds in terms of the spectral radius of weighted adjacency matrix by averaging temporal networks, e.g., periodic, nonperiodic Markovian networks, and a special nonperiodic non-Markovian network (the link activation network) in time...
September 11, 2017: IEEE Transactions on Cybernetics
https://www.readbyqxmd.com/read/28910764/efficient-message-passing-methods-with-fully-connected-models-for-early-vision
#12
Xiao Tan, Changming Sun, Fumin Shen, Kwan-Yee K Wong
Fully connected Markov random fields and conditional random fields have recently been shown to be advantageous in many early vision tasks being formulated as multi-labeling problems, such as stereo matching and image segmentation. The maximum posterior marginal (MPM) inference method in solving fully connected models uses a hybrid framework of mean-field (MF) method and a filtering like approach, and yields excellent results. In this paper, we extend this framework in several aspects. First, we provide an alternative inference method employing a fractional belief propagation based method instead of MF...
September 8, 2017: IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society
https://www.readbyqxmd.com/read/28910342/home-modification-to-reduce-falls-at-a-health-district-level-modeling-health-gain-health-inequalities-and-health-costs
#13
Nick Wilson, Giorgi Kvizhinadze, Frank Pega, Nisha Nair, Tony Blakely
BACKGROUND: There is some evidence that home safety assessment and modification (HSAM) is effective in reducing falls in older people. But there are various knowledge gaps, including around cost-effectiveness and also the impacts at a health district-level. METHODS AND FINDINGS: A previously established Markov macro-simulation model built for the whole New Zealand (NZ) population (Pega et al 2016, Injury Prevention) was enhanced and adapted to a health district level...
2017: PloS One
https://www.readbyqxmd.com/read/28903559/three-faces-of-n-acetylaspartate-activator-substrate-and-inhibitor-of-human-aspartoacylase
#14
Maria G Khrenova, Ekaterina D Kots, Sergey D Varfolomeev, Sofya V Lushchekina, Alexander V Nemukhin
Hydrolysis of N-acetylaspartate (NAA), one of the most concentrated metabolites in brain, catalyzed by human aspartoacylase (hAsp) shows a remarkable dependence of the reaction rate on substrate concentration. At low NAA concentrations, sigmoidal shape of kinetic curve is observed, followed by typical rate growth of the enzyme-catalyzed reaction, whereas at high NAA concentrations self-inhibition takes place. We show that this rate dependence is consistent with a molecular model, in which N-acetylaspartate appears to have three faces in the enzyme reaction, acting as activator at low concentrations, substrate at moderate concentrations, and inhibitor at high concentrations...
September 13, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28903016/arthroscopic-meniscectomy-for-degenerative-meniscal-tears-reduces-knee-pain-but-is-not-cost-effective-in-a-routine-health-care-setting-a-multi-center-longitudinal-observational-study-using-data-from-the-osteoarthritis-initiative
#15
Jan J Rongen, Tim M Govers, Pieter Buma, Maroeska M Rovers, Gerjon Hannink
OBJECTIVES: It is disputed whether arthroscopic meniscectomy is an (cost-) effective treatment for degenerative meniscus tears in day-to-day clinical practice. The objective of this study was to assess the cost-effectiveness of arthroscopic meniscectomy in subjects with knee osteoarthritis, in routine clinical practice, while taking into account the increased risk for future knee replacement surgery. We compared cost-effectiveness of arthroscopic meniscectomy compared to no surgery. DESIGN: - We used a state transition (Markov) simulation model to evaluate the cost-effectiveness of arthroscopic meniscectomy compared to no surgery in subjects with knee osteoarthritis (age range 45- 79 years)...
September 10, 2017: Osteoarthritis and Cartilage
https://www.readbyqxmd.com/read/28902880/cost-and-cost-effectiveness-of-a-school-based-education-program-to-reduce-salt-intake-in-children-and-their-families-in-china
#16
Xian Li, Stephen Jan, Lijing L Yan, Alison Hayes, Yunbo Chu, Haijun Wang, Xiangxian Feng, Wenyi Niu, Feng J He, Jun Ma, Yanbo Han, Graham A MacGregor, Yangfeng Wu
OBJECTIVE: The School-based Education Program to Reduce Salt Intake in Children and Their Families study was a cluster randomized control trial among grade five students in 28 primary schools and their families in Changzhi, China. It achieved a significant effect in lowering systolic blood pressure (SBP) in all family adults by 2.3 mmHg and in elderlies (aged > = 60 years) by 9.5 mmHg. The aim of this study was to assess the cost-effectiveness of this salt reduction program. METHODS: Costs of the intervention were assessed using an ingredients approach to identify resource use...
2017: PloS One
https://www.readbyqxmd.com/read/28901008/continuous-time-capture-recapture-in-closed-populations
#17
Matthew R Schofield, Richard J Barker, Nicholas Gelling
The standard approach to fitting capture-recapture data collected in continuous time involves arbitrarily forcing the data into a series of distinct discrete capture sessions. We show how continuous-time models can be fitted as easily as discrete-time alternatives. The likelihood is factored so that efficient Markov chain Monte Carlo algorithms can be implemented for Bayesian estimation, available online in the R package ctime. We consider goodness-of-fit tests for behavior and heterogeneity effects as well as implementing models that allow for such effects...
September 12, 2017: Biometrics
https://www.readbyqxmd.com/read/28900175/dynamic-and-kinetic-elements-of-%C3%A2%C2%B5-opioid-receptor-functional-selectivity
#18
Abhijeet Kapoor, Gerard Martinez-Rosell, Davide Provasi, Gianni de Fabritiis, Marta Filizola
While the therapeutic effect of opioids analgesics is mainly attributed to µ-opioid receptor (MOR) activation leading to G protein signaling, their side effects have mostly been linked to β-arrestin signaling. To shed light on the dynamic and kinetic elements underlying MOR functional selectivity, we carried out close to half millisecond high-throughput molecular dynamics simulations of MOR bound to a classical opioid drug (morphine) or a potent G protein-biased agonist (TRV-130). Statistical analyses of Markov state models built using this large simulation dataset combined with information theory enabled, for the first time: a) Identification of four distinct metastable regions along the activation pathway, b) Kinetic evidence of a different dynamic behavior of the receptor bound to a classical or G protein-biased opioid agonist, c) Identification of kinetically distinct conformational states to be used for the rational design of functionally selective ligands that may eventually be developed into improved drugs; d) Characterization of multiple activation/deactivation pathways of MOR, and e) Suggestion from calculated transition timescales that MOR conformational changes are not the rate-limiting step in receptor activation...
September 12, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28899625/cost-effectiveness-of-hpv-vaccination-in-the-context-of-high-cervical-cancer-incidence-and-low-screening-coverage
#19
Triin Võrno, Katrin Lutsar, Anneli Uusküla, Lee Padrik, Terje Raud, Rainer Reile, Oliver Nahkur, Raul-Allan Kiivet
BACKGROUND: Estonia has high cervical cancer incidence and low screening coverage. We modelled the impact of population-based bivalent, quadrivalent or nonavalent HPV vaccination alongside cervical cancer screening. METHODS: A Markov cohort model of the natural history of HPV infection was used to assess the cost-effectiveness of vaccinating a cohort of 12-year-old girls with bivalent, quadrivalent or nonavalent vaccine in two doses in a national, school-based vaccination programme...
September 9, 2017: Vaccine
https://www.readbyqxmd.com/read/28898249/projecting-social-contact-matrices-in-152-countries-using-contact-surveys-and-demographic-data
#20
Kiesha Prem, Alex R Cook, Mark Jit
Heterogeneities in contact networks have a major effect in determining whether a pathogen can become epidemic or persist at endemic levels. Epidemic models that determine which interventions can successfully prevent an outbreak need to account for social structure and mixing patterns. Contact patterns vary across age and locations (e.g. home, work, and school), and including them as predictors in transmission dynamic models of pathogens that spread socially will improve the models' realism. Data from population-based contact diaries in eight European countries from the POLYMOD study were projected to 144 other countries using a Bayesian hierarchical model that estimated the proclivity of age-and-location-specific contact patterns for the countries, using Markov chain Monte Carlo simulation...
September 12, 2017: PLoS Computational Biology
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