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https://www.readbyqxmd.com/read/28526243/histopathology-in-ureteropelvic-junction-obstruction-with-and-without-crossing-vessels
#1
Madeline Cancian, Gyan Pareek, Anthony Caldamone, Liza Aguiar, Hai Wang, Ali Amin
OBJECTIVE: To determine if the histopathology of the ureteropelvic junction differs between those with and without crossing vessels who present with a ureteropelvic junction obstruction. MATERIALS AND METHODS: Our database was queried for patients undergoing pyeloplasty (CPT 50400, 50405, 50544) between 6/1/2002 to 3/10/3016. We excluded patients with other renal anatomic abnormalities and patients undergoing surgery for upper tract tumor. One genitourinary pathologist reviewed all slides for muscle hypertrophy, fibrosis, edema and inflammation...
May 16, 2017: Urology
https://www.readbyqxmd.com/read/28525542/semiparametric-model-and-inference-for-spontaneous-abortion-data-with-a-cured-proportion-and-biased-sampling
#2
Jin Piao, Jing Ning, Christina D Chambers, Ronghui Xu
Evaluating and understanding the risk and safety of using medications for autoimmune disease in a woman during her pregnancy will help both clinicians and pregnant women to make better treatment decisions. However, utilizing spontaneous abortion (SAB) data collected in observational studies of pregnancy to derive valid inference poses two major challenges. First, the data from the observational cohort are not random samples of the target population due to the sampling mechanism. Pregnant women with early SAB are more likely to be excluded from the cohort, and there may be substantial differences between the observed SAB time and those in the target population...
May 18, 2017: Biostatistics
https://www.readbyqxmd.com/read/28523958/proportional-hazards-under-conway-maxwell-poisson-cure-rate-model-and-associated-inference
#3
N Balakrishnan, S Barui, F S Milienos
Cure rate models or long-term survival models play an important role in survival analysis and some other applied fields. In this article, by assuming a Conway-Maxwell-Poisson distribution under a competing cause scenario, we study a flexible cure rate model in which the lifetimes of non-cured individuals are described by a Cox's proportional hazard model with a Weibull hazard as the baseline function. Inference is then developed for a right censored data by the maximum likelihood method with the use of expectation-maximization algorithm and a profile likelihood approach for the estimation of the dispersion parameter of the Conway-Maxwell-Poisson distribution...
January 1, 2017: Statistical Methods in Medical Research
https://www.readbyqxmd.com/read/28521821/intratumoral-and-peritumoral-radiomics-for-the-pretreatment-prediction-of-pathological-complete-response-to-neoadjuvant-chemotherapy-based-on-breast-dce-mri
#4
Nathaniel M Braman, Maryam Etesami, Prateek Prasanna, Christina Dubchuk, Hannah Gilmore, Pallavi Tiwari, Donna Pletcha, Anant Madabhushi
BACKGROUND: In this study, we evaluated the ability of radiomic textural analysis of intratumoral and peritumoral regions on pretreatment breast cancer dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to predict pathological complete response (pCR) to neoadjuvant chemotherapy (NAC). METHODS: A total of 117 patients who had received NAC were retrospectively analyzed. Within the intratumoral and peritumoral regions of T1-weighted contrast-enhanced MRI scans, a total of 99 radiomic textural features were computed at multiple phases...
May 18, 2017: Breast Cancer Research: BCR
https://www.readbyqxmd.com/read/28521213/phylogenetic-analysis-of-an-epidemic-outbreak-of-acute-hepatitis-c-in-hiv-infected-patients-by-ultra-deep-pyrosequencing
#5
Noelia Caro-Pérez, María Martínez-Rebollar, Josep Gregori, Josep Quer, Patricia González, Martina Gambato, Neris García-González, Fernando González-Candelas, Josep Costa, Juan Ignacio Esteban, Josep Mallolas, Xavier Forns, Montse Laguno, Sofía Pérez-Del-Pulgar
BACKGROUND: The incidence of acute hepatitis C (AHC) among HIV-infected men who have sex with men (MSM) has increased significantly in the last 10 years. Several studies point to a social and sexual network of HIV-positive MSM that extends internationally. OBJECTIVES: The aim of our study was to investigate the dynamics of HCV transmission in an outbreak of AHC in HIV-infected MSM in Barcelona by ultra-deep pyrosequencing. STUDY DESIGN: Between 2008 and 2013, 113 cases of AHC in HIV-infected MSM were diagnosed in the Infectious Diseases Unit, Hospital Clínic, Barcelona...
May 10, 2017: Journal of Clinical Virology: the Official Publication of the Pan American Society for Clinical Virology
https://www.readbyqxmd.com/read/28520480/review-of-recent-methodological-developments-in-group-randomized-trials-part-2-analysis
#6
Elizabeth L Turner, Melanie Prague, John A Gallis, Fan Li, David M Murray
In 2004, Murray et al. reviewed methodological developments in the design and analysis of group-randomized trials (GRTs). We have updated that review with developments in analysis of the past 13 years, with a companion article to focus on developments in design. We discuss developments in the topics of the earlier review (e.g., methods for parallel-arm GRTs, individually randomized group-treatment trials, and missing data) and in new topics, including methods to account for multiple-level clustering and alternative estimation methods (e...
May 18, 2017: American Journal of Public Health
https://www.readbyqxmd.com/read/28516509/the-incidence-and-predictors-of-depressive-and-anxiety-symptoms-in-older-adults-with-vision-impairment-a-longitudinal-prospective-cohort-study
#7
Thomas J Heesterbeek, Hilde P A van der Aa, Ger H M B van Rens, Johannes W R Twisk, Ruth M A van Nispen
PURPOSE: Depression and anxiety are highly prevalent in older adults with vision impairment. Because symptoms of depression and anxiety appear to fluctuate, it is important to identify patients who are at risk of developing these symptoms for early diagnosis and treatment. Therefore, the aim of this study was to determine the incidence of subthreshold depression and anxiety, and to investigate predictors of developing symptoms of depression and anxiety in older adults with vision impairment who had no subthreshold depression or anxiety at baseline...
May 18, 2017: Ophthalmic & Physiological Optics: the Journal of the British College of Ophthalmic Opticians (Optometrists)
https://www.readbyqxmd.com/read/28515536/estimation-of-the-linear-mixed-integrated-ornstein-uhlenbeck-model
#8
Rachael A Hughes, Michael G Kenward, Jonathan A C Sterne, Kate Tilling
The linear mixed model with an added integrated Ornstein-Uhlenbeck (IOU) process (linear mixed IOU model) allows for serial correlation and estimation of the degree of derivative tracking. It is rarely used, partly due to the lack of available software. We implemented the linear mixed IOU model in Stata and using simulations we assessed the feasibility of fitting the model by restricted maximum likelihood when applied to balanced and unbalanced data. We compared different (1) optimization algorithms, (2) parameterizations of the IOU process, (3) data structures and (4) random-effects structures...
May 24, 2017: Journal of Statistical Computation and Simulation
https://www.readbyqxmd.com/read/28512748/genetic-influences-on-adhd-symptom-dimensions-examination-of-a-priori-candidates-gene-based-tests-genome-wide-variation-and-snp-heritability
#9
L Cinnamon Bidwell, Joshua C Gray, Jessica Weafer, Abraham A Palmer, Harriet de Wit, James MacKillop
Although the heritability of ADHD is estimated to be high, identifying specific genetic markers remains challenging. Most studies to date have examined the genetic basis of ADHD by employing dichotomous diagnostic phenotypes, but, as ADHD symptoms tend to be phenotypically dimensional, an alternative and potentially informative approach is to examine continuous indices of inattention and hyperactivity-impulsivity symptoms. The current study aimed to identify genetic effects on dimensionally-focused adult ADHD-related phenotypes in 990 individuals of European ancestry with intentionally low levels of substance misuse to avoid confounding...
June 2017: American Journal of Medical Genetics. Part B, Neuropsychiatric Genetics
https://www.readbyqxmd.com/read/28511838/supra-annular-valve-in-valve-implantation-reduces-blood-stasis-on-the-transcatheter-aortic-valve-leaflets
#10
Koohyar Vahidkhah, Ali N Azadani
Leaflet thrombosis following transcatheter aortic valve replacement (TAVR) and Valve-in-Valve (ViV) procedures has been increasingly recognized. This study aimed to investigate the effect of positioning of the transcatheter aortic valve (TAV) in ViV setting on the flow dynamics aspect of post-ViV thrombosis by quantifying the blood stasis in the intra-annular and supra-annular settings. To that end, two idealized computational models, representing ViV intra-annular and supra-annular positioning of a TAV were developed in a patient-specific geometry...
May 5, 2017: Journal of Biomechanics
https://www.readbyqxmd.com/read/28509612/defining-the-phylogenetic-position-of-amanita-species-from-andean-colombia
#11
Natalia Vargas, Carlos José Pardo-de La Hoz, Giovanna Danies, Ana Esperanza Franco-Molano, Pedro Jiménez, Silvia Restrepo, Alejandro Grajales
Amanita is a worldwide-distributed fungal genus, with approximately 600 known species. Most species within the genus are ectomycorrhizal (ECM), with some saprotrophic representatives. In this study, we constructed the first comprehensive phylogeny including ECM species from Colombia collected in native Quercus humboldtii forests and in introduced Pinus patula plantations. We included 8 species (A. brunneolocularis, A. colombiana, A. flavoconia, A. fuligineodisca, A. muscaria, A. rubescens, A. sororcula, and A...
April 12, 2017: Mycologia
https://www.readbyqxmd.com/read/28509564/maternal-time-use-and-nurturing-analysis-of-the-association-between-breastfeeding-practice-and-time-spent-interacting-with-baby
#12
Julie P Smith, Robert Forrester
BACKGROUND: Breastfeeding supports child development through complex mechanisms that are not well understood. Numerous studies have compared how well breastfeeding and nonbreastfeeding mothers interact with their child, but few examine how much interaction occurs. SUBJECTS AND METHODS: Our study of weekly time use among 156 mothers of infants aged 3-9 months investigated whether lactating mothers spend more time providing emotional support or cognitive stimulation of their infants than nonbreastfeeding mothers, and whether the amount of such interactive time is associated with breastfeeding intensity...
May 16, 2017: Breastfeeding Medicine: the Official Journal of the Academy of Breastfeeding Medicine
https://www.readbyqxmd.com/read/28508491/implementation-of-absolute-quantification-in-small-animal-spect-imaging-phantom-and-animal-studies
#13
Shabnam Khorasani Gerdekoohi, Naser Vosoughi, Kaveh Tanha, Majid Assadi, Pardis Ghafarian, Arman Rahmim, Mohammad Reza Ay
PURPOSE: Presence of photon attenuation severely challenges quantitative accuracy in single-photon emission computed tomography (SPECT) imaging. Subsequently, various attenuation correction methods have been developed to compensate for this degradation. The present study aims to implement an attenuation correction method and then to evaluate quantification accuracy of attenuation correction in small-animal SPECT imaging. METHODS: Images were reconstructed using an iterative reconstruction method based on the maximum-likelihood expectation maximization (MLEM) algorithm including resolution recovery...
May 16, 2017: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/28506839/evolutionary-relationships-among-protein-lysine-deacetylases-of-parasites-causing-neglected-diseases
#14
Larissa L S Scholte, Marina M Mourão, Fabiano Sviatopolk-Mirsky Pais, Jelena Melesina, Dina Robaa, Angela C Volpini, Wolfgang Sippl, Raymond J Pierce, Guilherme Oliveira, Laila A Nahum
The availability of the genomic data of diverse parasites provides an opportunity to identify new drug candidates against neglected tropical diseases affecting people worldwide. Histone modifying enzymes (HMEs) are potential candidates since they play key roles in the regulation of chromatin modifications, thus globally regulating gene expression. Furthermore, aberrant epigenetic states are often associated with human diseases, leading to great interest in HMEs as therapeutic targets. Our work focused on two families of protein lysine deacetylases (HDACs and sirtuins)...
May 13, 2017: Infection, Genetics and Evolution
https://www.readbyqxmd.com/read/28506651/a-load-to-fracture-and-strain-analysis-of-monolithic-zirconia-cantilevered-frameworks
#15
Faris A Alshahrani, Burak Yilmaz, Jeremy D Seidt, Edwin A McGlumphy, William A Brantley
STATEMENT OF PROBLEM: The dimensions of implant-supported fixed cantilevered prostheses are important to prevent mechanical and biological complications. Information on the optimum thickness and cantilever length for improving the strength of zirconia cantilevered frameworks is limited in the literature. PURPOSE: The purpose of this in vitro study was to investigate the effect of cantilever length and occlusocervical thickness on the load-to-fracture and strain distribution of zirconia frameworks...
May 12, 2017: Journal of Prosthetic Dentistry
https://www.readbyqxmd.com/read/28504925/comparative-diagnostic-test-evaluation-of-serum-procalcitonin-and-c-reactive-protein-in-suspected-bloodstream-infections-in-children-with-cancer
#16
Swapna R Nath, Sabeena Jayapalan, Harikumaran Nair, P Kusumakumary, N S Prema, T Priyakumari, K Rajamohanan
PURPOSE: To compute diagnostic test properties of C-reactive protein (CRP) and serum procalcitonin (PCT) levels in bloodstream infections in children with cancer and suspected sepsis, in comparison with blood culture as the gold standard. METHODOLOGY: Consecutive paediatric cancer patients, aged ≤14 years, with clinically suspected bloodstream infections were evaluated with blood culture and assay of PCT and CRP levels. Blood culture was taken as the gold standard for comparison...
May 15, 2017: Journal of Medical Microbiology
https://www.readbyqxmd.com/read/28504754/performance-comparison-of-pseudo-inverse-and-maximum-likelihood-estimators-of-stokes-parameters-in-the-presence-of-poisson-noise-for-spherical-design-based-measurement-structures
#17
François Goudail
Estimation of the Stokes vector from N>4 intensity measurements is usually performed with the pseudo-inverse (PI) estimator, which is optimal when the noise that corrupts the measurements is additive and Gaussian. In the presence of Poisson shot noise, the maximum-likelihood (ML) estimator is different from the PI estimator, but is more complex to implement since it is not closed-form. We compare in this Letter the precisions obtained with the ML and the PI estimators in the presence of Poisson noise when using measurement structures based on spherical designs...
May 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/28503760/the-penetrance-of-paraganglioma-and-pheochromocytoma-in-sdhb-germline-mutation-carriers
#18
Johannes A Rijken, Nicolasine D Niemeijer, Marianne A Jonker, Karin Eijkelenkamp, Jeroen C Jansen, Anouk van Berkel, Henri J L M Timmers, Henricus P M Kunst, Peter H L T Bisschop, Michiel N Kerstens, Koen M A Dreijerink, Marieke F van Dooren, Anouk N A van der Horst-Schrivers, Frederik J Hes, C René Leemans, Eleonora P M Corssmit, Erik F Hensen
Germline mutations in SDHB predispose to hereditary paraganglioma syndrome type 4. The risk of developing paraganglioma (PGL) or pheochromocytoma (PHEO) in SDHB mutation carriers is subject of recent debate. In the present nationwide cohort study of SDHB mutation carriers identified by the clinical genetics centers of the Netherlands, we have calculated the penetrance of SDHB associated tumors using a novel maximum likelihood estimator. This estimator addresses ascertainment bias and missing data on pedigree size and structure...
May 14, 2017: Clinical Genetics
https://www.readbyqxmd.com/read/28502652/comparative-and-evolutionary-analysis-of-an-adapter-molecule-myd88-in-invertebrate-metazoans
#19
Yipeng Ren, Junli Xue, Huanhuan Yang, Baoping Pan, Wenjun Bu
The myeloid differentiation factor 88 (MyD88) is an essential adapter in Toll-like receptor (TLR) signalling pathways, with TLR the first pattern-recognition receptor (PRR) that was discovered in Drosophila. In the present study, a MyD88 gene was identified and characterized from a commercially important shellfish, Scapharca subcrenata, including a DEATH domain and TIR domain conserved within other molluscs. Furthermore, comparative genomic evidence revealed that MyD88 was of different lengths and contained quantitative exon and intron regions, which might be involved in specific mechanisms...
May 11, 2017: Developmental and Comparative Immunology
https://www.readbyqxmd.com/read/28502279/evidence-and-molecular-characterization-of-bartonella-spp-and-hemoplasmas-in-neotropical-bats-in-brazil
#20
P Ikeda, M C Seki, A O T Carrasco, L V Rudiak, J M D Miranda, S M M Gonçalves, E G L Hoppe, A C A Albuquerque, M M G Teixeira, C E Passos, K Werther, R Z Machado, M R André
The order Chiroptera is considered the second largest group of mammals in the world, hosting important zoonotic virus and bacteria. Bartonella and hemotropic mycoplasmas are bacteria that parasite different mammals' species, including humans, causing different clinical manifestations. The present work aimed investigating the occurrence and assessing the phylogenetic positioning of Bartonella spp. and Mycoplasma spp. in neotropical bats sampled from Brazil. Between December 2015 and April 2016, 325 blood and/or tissues samples were collected from 162 bats comprising 19 different species sampled in five states of Brazil...
May 15, 2017: Epidemiology and Infection
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