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https://www.readbyqxmd.com/read/28340274/regularized-quantile-regression-applied-to-genome-enabled-prediction-of-quantitative-traits
#1
M Nascimento, F F E Silva, M D V de Resende, C D Cruz, A C C Nascimento, J M S Viana, C F Azevedo, L M A Barroso
Genomic selection (GS) is a variant of marker-assisted selection, in which genetic markers covering the whole genome predict individual genetic merits for breeding. GS increases the accuracy of breeding values (BV) prediction. Although a variety of statistical models have been proposed to estimate BV in GS, few methodologies have examined statistical challenges based on non-normal phenotypic distributions, e.g., skewed distributions. Traditional GS models estimate changes in the phenotype distribution mean, i...
March 22, 2017: Genetics and Molecular Research: GMR
https://www.readbyqxmd.com/read/28340227/transplant-as-a-competing-risk-in-the-analysis-of-dialysis-patients
#2
Nan van Geloven, Saskia le Cessie, Friedo W Dekker, Hein Putter
Time-to-event analyses are frequently used in nephrology research, for instance, when recording time to death or time to peritonitis in dialysis patients. Many papers have pointed out the important issue of competing events (or competing risks) in such analyses. For example, when studying one particular cause of death it can be noted that patients also die from other causes. Such competing events preclude the event of interest from occurring and thereby complicate the statistical analysis. The Kaplan-Meier approach to calculating the cumulative probability of the event of interest yields invalid results in the presence of competing risks, thus the alternative cumulative incidence competing risk (CICR) approach has become the standard...
March 3, 2017: Nephrology, Dialysis, Transplantation
https://www.readbyqxmd.com/read/28340206/monitoring-the-quality-of-cardiac-surgery-based-on-three-or-more-surgical-outcomes-using-a-new-variable-life-adjusted-display
#3
Fah Fatt Gan, Xu Tang, Yexin Zhu, Puay Weng Lim
Quality problem or issue: The traditional variable life-adjusted display (VLAD) is a graphical display of the difference between expected and actual cumulative deaths. The VLAD assumes binary outcomes: death within 30 days of an operation or survival beyond 30 days. Full recovery and bedridden for life, for example, are considered the same outcome. This binary classification results in a great loss of information. Initial assessment: Although there are many grades of survival, the binary outcomes are commonly used to classify surgical outcomes...
March 17, 2017: International Journal for Quality in Health Care
https://www.readbyqxmd.com/read/28340131/interobserver-variability-in-histologic-evaluation-of-liver-fibrosis-using-categorical-and-quantitative-scores
#4
Michael Pavlides, Jacqueline Birks, Eve Fryer, David Delaney, Nikita Sarania, Rajarshi Banerjee, Stefan Neubauer, Eleanor Barnes, Kenneth A Fleming, Lai Mun Wang
Objectives: The aim of the study was to investigate the interobserver agreement for categorical and quantitative scores of liver fibrosis. Methods: Sixty-five consecutive biopsy specimens from patients with mixed liver disease etiologies were assessed by three pathologists using the Ishak and nonalcoholic steatohepatitis Clinical Research Network (NASH CRN) scoring systems, and the fibrosis area (collagen proportionate area [CPA]) was estimated by visual inspection (visual-CPA)...
March 15, 2017: American Journal of Clinical Pathology
https://www.readbyqxmd.com/read/28340065/the-next-three-decades-of-the-comet-assay-a-report-of-the-11th-international-comet-assay-workshop
#5
Gudrun Koppen, Amaya Azqueta, Bertrand Pourrut, Gunnar Brunborg, Andrew R Collins, Sabine A S Langie
The International Comet Assay Workshops are a series of scientific conferences dealing with practical and theoretical aspects of the Comet Assay (single-cell gel electrophoresis)-a simple method for detecting DNA strand breaks. The first paper describing such an assay was published over 30 years ago in 1984 by Swedish researchers O. Ostling and K. J. Johanson. Appropriately, the theme for the 2015 meeting was looking to the future: 'The Next 3 Decades of the Comet Assay'. The programme included 25 oral and 43 poster presentations depicting the latest advances in technical developments as well as applications of the comet assay in genotoxicity testing (in vitro and in vivo) and biomonitoring of both humans and the environment...
March 4, 2017: Mutagenesis
https://www.readbyqxmd.com/read/28339748/genotype-based-gene-signature-of-glioma-risk
#6
Yen-Tsung Huang, Yi Zhang, Zhijin Wu, Dominique S Michaud
Background.: Glioma accounts for 80% of malignant brain tumors, but its etiologic determinants remain elusive. Despite genetic susceptibility loci identified by genome-wide association study (GWAS), the agnostic approach leaves open the possibility that other susceptibility genes remain to be discovered. Here we conduct a gene-centric integrative GWAS (iGWAS) of glioma risk that combines transcriptomics and genetics. Methods.: We synthesized a brain transcriptomics dataset (n = 354), a GWAS dataset (n = 4203), and an advanced glioma tumor transcriptomic dataset (n = 483) to conduct an iGWAS...
February 22, 2017: Neuro-oncology
https://www.readbyqxmd.com/read/28339569/acrolein-yields-in-mainstream-smoke-from-commercial-cigarette-and-little-cigar-tobacco-products
#7
Todd L Cecil, Tim M Brewer, Mimy Young, Matthew R Holman
Introduction: Many carbonyls are produced from the combustion of tobacco products and many of these carbonyls are harmful or potentially harmful constituents of mainstream cigarette smoke. One carbonyl of particular interest is acrolein, which is formed from the incomplete combustion of organic matter and the most significant contributor to non-cancer respiratory effects from cigarette smoke. Sheet-wrapped cigars, also known as "little cigars," are a type of tobacco products that have not been extensively investigated in literature...
January 19, 2017: Nicotine & Tobacco Research: Official Journal of the Society for Research on Nicotine and Tobacco
https://www.readbyqxmd.com/read/28339429/comparing-the-efficacy-of-surgery-and-medical-therapy-for-pain-management-in-endometriosis-a-systematic-review-and-meta-analysis
#8
Shahla Chaichian, Ali Kabir, Adolfazl Mehdizadehkashi, Khaled Rahmani, Mehrdad Moghimi, Bahram Moazzami
BACKGROUND: Pain is considered as one of the main symptoms of endometriosis. The treatment for endometriosis remains controversial. OBJECTIVES: The aim of this study is to compare the effect of medical or surgical treatments for pain-relief in patients with endometriosis. STUDY DESIGN: Systematic review and meta-analysis. SETTING: Published papers about evaluating pain treatment in endometriosis in PubMed, Scopus, and Google Scholar...
March 2017: Pain Physician
https://www.readbyqxmd.com/read/28339424/comparison-of-weight-loss-ghrelin-and-leptin-hormones-after-ligation-of-left-gastric-artery-and-sleeve-gastrectomy-in-a-rat-model
#9
Erkan Yardimci, Suleyman Bozkurt, Merve Busra Cengiz, Fatma Umit Malya
BACKGROUND Ligation of the left gastric artery (LLGA), which supplies the fundus of the stomach, may reduce the appetite hormone ghrelin, resulting in weight control. The aim of this study was to compare LLGA and sleeve gastrectomy (SG) in terms of postoperative outcomes in a rat model. MATERIAL AND METHODS Fifteen male Wistar albino rats, weighing >350 grams (range 350-525 grams), were enrolled in LLGA (N=5), SG (N=5), and control (N=5) groups. Blood samples were drawn preoperatively and also during the first and fourth week postoperatively to assay ghrelin and leptin hormone levels...
March 24, 2017: Medical Science Monitor: International Medical Journal of Experimental and Clinical Research
https://www.readbyqxmd.com/read/28339418/survey-of-kinesiologists-functional-capacity-evaluation-practice-in-canada
#10
Kathryn E Sinden, Taya L McGillivary, Elizabeth Chapman, Steven L Fischer
BACKGROUND: In Canada, functional capacity evaluations (FCEs) are commonly administered by several health care professions including kinesiologists. Kinesiologists have been recently regulated as health care professionals in Ontario and we know little about their demographics, the frequency of FCE administration, or the types of FCEs used by this group. OBJECTIVE: The purposes of this study were to identify: 1) the demographic characteristics and FCE education of kinesiology FCE practitioners; 2) the FCE systems most used by these practitioners and 3) the constructs from assessments used to determine functional capacity...
March 23, 2017: Work: a Journal of Prevention, Assessment, and Rehabilitation
https://www.readbyqxmd.com/read/28339382/menopausal-symptom-relief-and-side-effects-experienced-by-women-using-compounded-bioidentical-hormone-replacement-therapy-and-synthetic-conjugated-equine-estrogen-and-or-progestin-hormone-replacement-therapy-part-2
#11
Laura J Deleruyelle
The use of compounded bioidentical hormone replacement therapy by menopausal women has become a popular alternative to traditional synthetic conjugated equine estrogen and progestin hormone replacement therapy due to safety concerns raised by recent studies. However, due to the lack of randomized, large-scale trials to evaluate the efficacy and side-effect profile of compounded bioidentical hormone replacement therapy many healthcare providers are reluctant to prescribe such therapy. The purpose of this study was to compare women's menopausal symptom relief and side effects experienced when using compounded bioidentical hormone replacement therapy and traditional hormone replacement therapy...
November 2016: International Journal of Pharmaceutical Compounding
https://www.readbyqxmd.com/read/28339311/lung-rads-category-4x-does-it-improve-prediction-of-malignancy-in-subsolid-nodules
#12
Kaman Chung, Colin Jacobs, Ernst T Scholten, Jin Mo Goo, Helmut Prosch, Nicola Sverzellati, Francesco Ciompi, Onno M Mets, Paul K Gerke, Mathias Prokop, Bram van Ginneken, Cornelia M Schaefer-Prokop
Purpose To evaluate the added value of Lung CT Screening Reporting and Data System (Lung-RADS) assessment category 4X over categories 3, 4A, and 4B for differentiating between benign and malignant subsolid nodules (SSNs). Materials and Methods SSNs on all baseline computed tomographic (CT) scans from the National Lung Cancer Trial that would have been classified as Lung-RADS category 3 or higher were identified, resulting in 374 SSNs for analysis. An experienced screening radiologist volumetrically segmented all solid cores and located all malignant SSNs visible on baseline scans...
March 24, 2017: Radiology
https://www.readbyqxmd.com/read/28339162/sofosbuvir-based-treatment-is-safe-and-effective-in-indian-hepatitis-c-patients-on-maintenance-haemodialysis-a-retrospective-study
#13
Mohammed Shujauddin Akhil, Balaji Kirushnan, Melvin Martin, Kanakaraj Arumugam, N K Ganesh Prasad, Rajan Ravichandran
AIM: This study evaluates the safety and efficacy of direct-acting antivirals (DAAs) including sofosbuvir, ledipasvir and daclatasvir in patients with hepatitis C viraemia who were on maintenance haemodialysis METHODS: Data on patients who received sofosbuvir and ribavirin were analysed. Patients who experienced treatment failure with the above regimen received sofosbuvir and ledipasvir for infection with HCV genotype 1. Those having HCV genotype 3 infection received sofosbuvir and daclatasvir...
March 24, 2017: Nephrology
https://www.readbyqxmd.com/read/28339110/a-fast-non-iterative-approach-for-accelerated-high-temporal-resolution-cine-cmr-using-dynamically-interleaved-streak-removal-in-the-power-spectral-encoded-domain-with-low-pass-filtering-dispel-and-modulo-prime-spokes-mops
#14
Keigo Kawaji, Mita B Patel, Charles G Cantrell, Akiko Tanaka, Marco Marino, Satoshi Tamura, Hui Wang, Yi Wang, Timothy J Carroll, Takeyoshi Ota, Amit R Patel
PURPOSE: To introduce a pair of accelerated non-Cartesian acquisition principles that when combined, exploit the periodicity of k-space acquisition, and thereby enable acquisition of high-temporal cine-Cardiac Magnetic Resonance (CMR). METHODS: The mathematical formulation of a non-iterative, undersampled non-Cartesian cine acquisition and reconstruction is presented. First, a low-pass-filtering step that exploits streaking artifact redundancy is provided; (i.e...
March 24, 2017: Medical Physics
https://www.readbyqxmd.com/read/28338910/the-dry-run-analysis-a-method-for-evaluating-risk-scores-for-confounding-control
#15
Richard Wyss, Ben B Hansen, Alan R Ellis, Joshua J Gagne, Rishi J Desai, Robert J Glynn, Til Stürmer
A propensity score (PS) model's ability to control confounding can be assessed by evaluating covariate balance across exposure groups after PS adjustment. The optimal strategy for evaluating a disease risk score (DRS) model's ability to control confounding is less clear. DRS models cannot be evaluated through balance checks within the full population, and they are usually assessed through prediction diagnostics and goodness-of-fit tests. A proposed alternative is the "dry-run" analysis, which divides the unexposed population into "pseudo-exposed" and "pseudo-unexposed" groups so that differences on observed covariates resemble differences between the actual exposed and unexposed populations...
March 6, 2017: American Journal of Epidemiology
https://www.readbyqxmd.com/read/28338852/the-growth-of-biostatistics-and-estimation-of-cancer-risk-estimates-past-current-and-future-challenges
#16
Dale L Preston, Daniel O Stram
There has been a long process of growth and development of statistical approaches to the analysis of cancer incidence and mortality data obtained from the follow-up of radiation exposed populations. The challenges of radiation risk analysis provided impetus for innovative statistical methods, including, the inception and continued improvement of hazard rate regression methods. Key statistical contributions that improved cancer risk estimation include statistical advances pertaining to the measurement error problem...
March 2, 2017: Radiation Protection Dosimetry
https://www.readbyqxmd.com/read/28338663/prevalence-and-associated-factors-of-blepharoptosis-in-korean-adult-population-the-korea-national-health-and-nutrition-examination-survey-2008-2011
#17
M H Kim, J Cho, D Zhao, K I Woo, Y-D Kim, S Kim, S W Yang
PurposeThis study aimed to evaluate the prevalence and associated factors of involutional blepharoptosis in a nationwide representative sample in Korea.MethodsCross-sectional study 20 941 Korean men and women 40 years of age and older who participated in last 2 years (2008 and 2009) of the 4th wave of the Korean National Health and Nutrition Examination Survey (KNHANES) IV and the first 2 years (2010 and 2011) of KNHANES V. Ocular examinations were performed by ophthalmologists trained in procedure and grading methods, and blepharoptosis was defined as a marginal reflex distance <2 mm on either eye...
March 24, 2017: Eye
https://www.readbyqxmd.com/read/28338557/ruthenium-106-brachytherapy-in-the-treatment-of-circumscribed-choroidal-hemangioma
#18
Masood Naseripour, Arash Maleki, Arezoo Astaraki, Ahad Sedaghat, Ramin Jaberi, Stacey Lee, Zohreh Azma, Sukhum Silpa-Archa
PURPOSE: To examine the efficacy and safety of Ruthenium-106 plaque radiotherapy in the treatment of circumscribed choroidal hemangioma. METHODS: Twenty-one eyes of 21 patients diagnosed with symptomatic circumscribed choroidal hemangioma who underwent Ruthenium-106 plaque radiotherapy were included in the study. Clinical response, ancillary tests finding improvement, and major side effects were evaluated. RESULTS: From the initial to the 1-year follow-up visits, vision improved in 12 eyes (57%), was stable in 7 eyes (33%), and became worse in 2 eyes (10%)...
March 23, 2017: Retina
https://www.readbyqxmd.com/read/28338455/long-term-administration-of-bisphosphonate-to-reduce-local-recurrence-of-sacral-giant-cell-tumor-after-nerve-sparing-surgery
#19
Wei Xu, Yu Wang, Jing Wang, Xinghai Yang, Weibo Liu, Wang Zhou, Tielong Liu, Jianru Xiao
OBJECTIVE The objective of this study was to investigate the effect of long-term bisphosphonate treatment on reducing local recurrence of sacral giant cell tumors (GCTs) after nerve-sparing surgery. METHODS Thirty-five consecutive patients with sacral GCTs who received treatment in Shanghai Changzheng Hospital between January 2000 and December 2010 were included in this study. Between January 2007 and December 2010, 19 patients received bisphosphonates following nerve-sparing surgery. Before January 2007, 16 patients received nerve-sparing surgery alone, and these cases were included as the control group...
March 24, 2017: Journal of Neurosurgery. Spine
https://www.readbyqxmd.com/read/28338445/socioeconomic-status-and-outcomes-after-sport-related-concussion-a-preliminary-investigation
#20
Scott L Zuckerman, Brian Holt Zalneraitis, Douglas J Totten, Kolin E Rubel, Andrew W Kuhn, Aaron M Yengo-Kahn, Christopher M Bonfield, Allen K Sills, Gary S Solomon
OBJECTIVE A significant proportion of patients experience long-term symptoms after sport-related concussion (SRC), and several factors have been associated with this protracted recovery. Limited data exist on the role of socioeconomic status (SES) on SRC outcomes. The objective in this study was to conduct a preliminary investigation to determine the effect of SES on outcomes after SRC in student-athletes treated at a regional sports concussion center. METHODS A retrospective cohort study of 282 middle school, high school, and collegiate student-athletes was conducted...
March 24, 2017: Journal of Neurosurgery. Pediatrics
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