keyword
MENU ▼
Read by QxMD icon Read
search

Predictive value

keyword
https://www.readbyqxmd.com/read/28088842/unbiased-split-variable-selection-for-random-survival-forests-using-maximally-selected-rank-statistics
#1
Marvin N Wright, Theresa Dankowski, Andreas Ziegler
The most popular approach for analyzing survival data is the Cox regression model. The Cox model may, however, be misspecified, and its proportionality assumption may not always be fulfilled. An alternative approach for survival prediction is random forests for survival outcomes. The standard split criterion for random survival forests is the log-rank test statistic, which favors splitting variables with many possible split points. Conditional inference forests avoid this split variable selection bias. However, linear rank statistics are utilized by default in conditional inference forests to select the optimal splitting variable, which cannot detect non-linear effects in the independent variables...
January 15, 2017: Statistics in Medicine
https://www.readbyqxmd.com/read/28088839/pharmacokinetic-pharmacodynamic-modeling-of-the-pde4-inhibitor-tak-648-in-type-2-diabetes-early-translational-approaches-for-human-dose-prediction
#2
N Plock, S Vollert, M Mayer, G Hanauer, G Lahu
TAK-648 is a PDE4 inhibitor with demonstrated preclinical antidiabetic properties. Our objective was to develop a translational pharmacokinetic/pharmacodynamic (PK/PD) model for human type 2 diabetes (T2D) dose prediction using HbA1c results from a db/db mouse study. Estimated parameters in combination with tPDE4i values calculated for the clinical roflumilast dose of 500 μg were used to translate preclinical effects of TAK-648 to required exposure in humans. A first-in-human study with single TAK-648 doses of 0...
January 15, 2017: Clinical and Translational Science
https://www.readbyqxmd.com/read/28088797/automated-interpretation-of-pulmonary-function-tests-in-adults-with-respiratory-complaints
#3
Marko Topalovic, Stefan Laval, Jean-Marie Aerts, Thierry Troosters, Marc Decramer, Wim Janssens
BACKGROUND: The use of pulmonary function tests is primarily based on expert opinion and international guidelines. Current interpretation strategies are using predefined cutoffs for the description of a typical pattern. OBJECTIVES: We aimed to explore the predicted disease outcome based on the American Thoracic Society/European Respiratory Society (ATS/ERS) interpreting strategy. Subsequently, we investigated whether an unbiased machine learning framework integrating lung function with clinical variables may provide alternative decision trees resulting in a more accurate diagnosis...
January 12, 2017: Respiration; International Review of Thoracic Diseases
https://www.readbyqxmd.com/read/28088792/impact-of-nudt15-polymorphisms-on-thiopurines-induced-myelotoxicity-and-thiopurines-tolerance-dose
#4
Dandan Yin, Xuyang Xia, Junlong Zhang, Shouyue Zhang, Fei Liao, Ge Zhang, Yan Zhang, Qianqian Hou, Xue Yang, Hong Wang, Zhigui Ma, Heyao Wang, Yiping Zhu, Wei Zhang, Yuelan Wang, Bo Liu, Lanlan Wang, Heng Xu, Yang Shu
Thiopurines are widely used as anticancer and immunosuppressive agents. However, life-threatening myelotoxicity has been noticed and largely explained by genetic variations, including NUDT15 polymorphisms (e.g., rs116855232). In this study, we conduct a meta-analysis to investigate the impact of rs116855232 on thiopurines-induced myelotoxicity susceptibility (1752 patients from 7 independent cohorts), as well as on thiopurines intolerance dose (2745 patients from 13 cohorts). Variant allele of rs116855232 contributes 7...
January 11, 2017: Oncotarget
https://www.readbyqxmd.com/read/28088638/the-dlno-dlco-ratio-physiological-significance-and-clinical-implications
#5
J M B Hughes, A T Dinh-Xuan
DLNO/DLCO directly measures the ratio of the diffusing capacities of the lung for nitric oxide (NO) and carbon monoxide (CO). In terms of the Roughton and Forster, 1957; equation, 1/DL=1/Dm+1/θVc, where Dm is the membrane (Dm) and θVc is the red cell component of the overall diffusing conductance (DL), DLNO mostly reflects the Dm component and DLCO the θVc red cell component. The DLNO/DLCO ratio is positively related to the DmCO/Vc ratio and the CO red cell resistance (1/θCOVc) as a percentage of the total resistance (1/DLCO), independent of the absolute values of DLNO or DLCO...
January 11, 2017: Respiratory Physiology & Neurobiology
https://www.readbyqxmd.com/read/28088633/quantitative-analysis-of-lab-to-lab-variability-in-caco-2-permeability-assays
#6
Jong Bong Lee, Atheer Zgair, Dhiaa A Taha, Xiaowei Zang, Leonid Kagan, Tae Hwan Kim, Min Gi Kim, Hwi-Yeol Yun, Peter M Fischer, Pavel Gershkovich
In this study, Caco-2 permeability results from different laboratories were compared. Six different sets of apparent permeability coefficient (Papp) values reported in the literature were compared to experimental Papp obtained in our laboratory. The differences were assessed by determining the root mean square error (RMSE) values between the datasets, which reached levels as high as 0.581 for the training set compounds, i.e. ten compounds with known effective human permeability (Peff). The consequences of these differences in Papp for prediction of oral drug absorption were demonstrated by introducing the Papp into the absorption and pharmacokinetics simulation software application GastroPlus(TM) for prediction of the fraction absorbed (Fa) in humans using calibrated "user-defined permeability models"...
January 11, 2017: European Journal of Pharmaceutics and Biopharmaceutics
https://www.readbyqxmd.com/read/28088598/are-the-current-guidelines-for-the-surgical-management-of-intraductal-papillary-mucinous-neoplasms-of-the-pancreas-adequate-a-multi-institutional-study
#7
Gregory C Wilson, Shishir K Maithel, David Bentrem, Daniel E Abbott, Sharon Weber, Clifford Cho, Robert Cg Martin, Charles R Scoggins, Hong Jin Kim, Nipun B Merchant, David A Kooby, Michael J Edwards, Syed A Ahmad
BACKGROUND: Controversy persists regarding the management of patients with IPMN. International consensus guidelines stratify patients into high risk, worrisome, and low risk categories. STUDY DESIGN: The medical records of 7 institutions were reviewed for patients that underwent surgical management of IPMN between 2000-2015. RESULTS: 324 patients were included in the analysis. 60.4% of patients had main-duct / mixed type, and 39.7% had branch-duct IPMN...
January 11, 2017: Journal of the American College of Surgeons
https://www.readbyqxmd.com/read/28088499/initial-uncertainty-impacts-statistical-learning-in-sound-sequence-processing
#8
Juanita Todd, Alexander Provost, Lisa Whitson, Daniel Mullens
This paper features two studies confirming a lasting impact of first learning on how subsequent experience is weighted in early relevance-filtering processes. In both studies participants were exposed to sequences of sound that contained a regular pattern on two different timescales. Regular patterning in sound is readily detected by the auditory system and used to form "prediction models" that define the most likely properties of sound to be encountered in a given context. The presence and strength of these prediction models is inferred from changes in automatically elicited components of auditory evoked potentials...
January 11, 2017: Journal of Physiology, Paris
https://www.readbyqxmd.com/read/28088459/strain-development-in-bulk-filled-cavities-of-different-depths-characterized-using-a-non-destructive-acoustic-emission-approach
#9
Annelies Van Ende, Diogo Pedrollo Lise, Jan De Munck, Johan Vanhulst, Martine Wevers, Bart Van Meerbeek
OBJECTIVES: (1) To evaluate the effect of cavity depth and composite type on the interfacial debonding in bulk-filled cavities. (2) To correlate the theoretical shrinkage stress and the level of interfacial debonding determined by acoustic emission (AE). METHODS: 80 sound molars were divided in two groups to receive a Class-I cavity (3.5×3.5mm) with 2.5- or 4.0-mm depth. The cavities were restored with either a conventional paste-like (Filtek Z100, 3M ESPE), a conventional flowable (G-ænial Universal Flo, GC), a bulk-fill paste-like (Tetric EvoCeram Bulk Fill, Ivoclar Vivadent) or a bulk-fill flowable (SDR, Dentsply) composite (n=10)...
January 11, 2017: Dental Materials: Official Publication of the Academy of Dental Materials
https://www.readbyqxmd.com/read/28088404/variation-in-fat-globule-size-in-bovine-milk-and-its-prediction-using-mid-infrared-spectroscopy
#10
A Fleming, F S Schenkel, J Chen, F Malchiodi, R A Ali, B Mallard, M Sargolzaei, M Corredig, F Miglior
The objectives of this study were to investigate the sources of variation in milk fat globule (MFG) size in bovine milk and its prediction using mid-infrared (MIR) spectroscopy. Mean MFG size was measured in 2,076 milk samples from 399 Ayrshire, Brown Swiss, Holstein, and Jersey cows, and expressed as volume moment mean (D[4,3]) and surface moment mean (D[3,2]). The mid-infrared spectra of the samples and milk performance data were also recorded during routine milk recording and testing. The effects of breed, herd nested within breed, days in milk, season, milking period, age at calving, parity, and individual animal on the variation observed in MFG size were investigated...
January 11, 2017: Journal of Dairy Science
https://www.readbyqxmd.com/read/28088319/ercc1-and-ercc2-as-predictive-biomarkers-to-oxaliplatin-based-chemotherapy-in-colorectal-cancer-patients-from-egypt
#11
Amira B Kassem, Salem EidSalem, Mohamed E Abdelrahim, Amira S A Said, Ahmad Salahuddin, Marwa Mahmoud Hussein, Abeer A Bahnassy
BACKGROUND: The impact of Excision repair cross-complementation group 1 (ERCC1) and group 2 (ERCC2) expression levels on the efficacy of oxaliplatin-based chemotherapy is still controversial. The present study was conducted to determine the predictive value of these molecular biomarkers in stage III and IV colorectal cancer (CRC) patients receiving oxaliplatin (OX) - based chemotherapy as first-line treatment. METHODS: The study included 80 CRC patients who received first line oxaliplatin based chemotherapy The expression levels of ERCC1 and ERCC2-mRNA and proteins were determined in the primary tumors by quantitative real time reverse transcription polymerase chain reaction(RT-qPCR) and immunohistochemistry (IHC); respectively...
January 11, 2017: Experimental and Molecular Pathology
https://www.readbyqxmd.com/read/28088230/relationship-between-the-uptake-of-18-f-borono-l-phenylalanine-and-l-methyl-11-c-methionine-in-head-and-neck-tumors-and-normal-organs
#12
Yoshiaki Watanabe, Hiroaki Kurihara, Jun Itami, Ryohei Sasaki, Yasuaki Arai, Kazuro Sugimura
BACKGROUND AND PURPOSE: The purpose of this study was to determine the distribution of 4-borono-2-(18)F-fluoro-phenylalanine ((18)F-BPA) and L-[methyl-(11)C] methionine ((11)C-Met) in normal organs and tumors and to evaluate the usefulness of (11)C-Met/PET in screening potential candidates for boron neutron capture therapy (BNCT). MATERIAL METHODS: Seven patients who had at least one histologically confirmed head and neck tumor were included in this study. They underwent both whole-body (18)F-BPA-PET/CT and (11)C-Met-PET/CT within a span of 6 months...
January 14, 2017: Radiation Oncology
https://www.readbyqxmd.com/read/28088134/dirac-bubble-potential-for-he-he-and-inadequacies-in-the-continuum-comparing-an-analytic-model-with-elastic-collision-experiments
#13
Michael Chrysos
We focus on the long-pending issue of the inadequacy of the Dirac bubble potential model in the description of He-He interactions in the continuum [L. L. Lohr and S. M. Blinder, Int. J. Quantum Chem. 53, 413 (1995)]. We attribute this failure to the lack of a potential wall to mimic the onset of the repulsive interaction at close range separations. This observation offers the explanation to why this excessively simple model proves incapable of quantitatively reproducing previous experimental findings of glory scattering in He-He, although being notorious for its capability of reproducing several distinctive features of the atomic and isotopic helium dimers and trimers [L...
January 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28088023/a-novel-model-to-predict-gas-phase-hydroxyl-radical-oxidation-kinetics-of-polychlorinated-compounds
#14
Shuang Luo, Zongsu Wei, Richard Spinney, Zhihui Yang, Liyuan Chai, Ruiyang Xiao
In this study, a novel model based on aromatic meta-substituent grouping was presented to predict the second-order rate constants (k) for OH oxidation of PCBs in gas-phase. Since the oxidation kinetics are dependent on the chlorination degree and position, we hypothesized that it may be more accurate for k value prediction if we group PCB congeners based on substitution positions (i.e., ortho (o), meta (m), and para (p)). To test this hypothesis, we examined the correlation of polarizability (α), a quantum chemical based descriptor for k values, with an empirical Hammett constant (σ(+)) on each substitution position...
January 4, 2017: Chemosphere
https://www.readbyqxmd.com/read/28087924/clinical-testing-of-tuberculosis-vaccine-candidates
#15
Mark Hatherill, Dereck Tait, Helen McShane
It is almost 100 years since the development of bacille Calmette-Guérin (BCG), the only licensed vaccine against tuberculosis (TB). While BCG does confer consistent protection against disseminated disease, there is an urgent need for a more effective vaccine against pulmonary disease. There are several indications for such an improved vaccine, including prevention of infection, prevention of disease, and a therapeutic vaccine to prevent recurrent disease. The two main approaches to TB vaccine development are developing an improved whole mycobacterial priming agent to replace BCG and/or developing a subunit booster vaccine to be administered after a BCG or BCG replacement priming vaccination...
October 2016: Microbiology Spectrum
https://www.readbyqxmd.com/read/28087902/a-review-of-the-preventability-of-maternal-mortality-in-one-hospital-system-in-louisiana-usa
#16
James J Morong, Jane K Martin, Robert S Ware, Alfred G Robichaux
OBJECTIVE: To determine preventability of in-hospital maternal mortality in the Ochsner Health System (OHS) in the US state of Louisiana. METHODS: A retrospective study was undertaken of all known cases of in-hospital maternal death (during pregnancy or within 42 days of termination) that occurred within OHS facilities in 1995-2013. Associations between characteristics and mortality and preventability were investigated. Incidence rate ratios (IRRs) were calculated in view of varying reference values...
December 9, 2016: International Journal of Gynaecology and Obstetrics
https://www.readbyqxmd.com/read/28087564/right-ventricular-ejection-fraction-is-incremental-to-left-ventricular-ejection-fraction-for-the-prediction-of-future-arrhythmic-events-in-patients-with-systolic-dysfunction
#17
Yoko Mikami, Umjeet Jolly, Bobak Heydari, Mingkai Peng, Fahad Almehmadi, Mohammed Zahrani, Mahmoud Bokhari, John Stirrat, Carmen P Lydell, Andrew G Howarth, Raymond Yee, James A White
BACKGROUND: Left ventricular ejection fraction remains the primary risk stratification tool used in the selection of patients for implantable cardioverter defibrillator therapy. However, this solitary marker fails to identify a substantial portion of patients experiencing sudden cardiac arrest. In this study, we examined the incremental value of considering right ventricular ejection fraction for the prediction of future arrhythmic events in patients with systolic dysfunction using the gold standard of cardiovascular magnetic resonance...
January 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28087513/how-accurate-is-a-single-cutpoint-to-identify-high-blood-pressure-in-adolescents
#18
Paolo Brambilla, Anita Andreano, Laura Antolini, Giorgio Bedogni, Alessandro Salvatoni, Lorenzo Iughetti, Luis Alberto Moreno, Angelo Pietrobelli, Simonetta Genovesi
In 2007 the International Diabetes Federation (IDF) proposed single blood pressure (BP) cutpoints (systolic: ≥130 mm Hg and diastolic: ≥85 mm Hg) for the diagnosis of high blood pressure (HBP) in adolescents. Before this proposal, HBP had been defined as BP at or above the 95th percentile for age, sex, and height percentile (reference standard). In this study, we evaluated the risk for misclassification when using the IDF single-cutpoints criteria. We first applied the IDF criteria to a reconstructed population with the same age, sex, and height distribution as the population used to develop the reference standard...
January 13, 2017: American Journal of Epidemiology
https://www.readbyqxmd.com/read/28087371/use-of-the-heart-pathway-with-high-sensitivity-cardiac-troponins-a-secondary-analysis
#19
Simon A Mahler, Jason P Stopyra, Fred S Apple, Robert F Riley, Gregory B Russell, Brian C Hiestand, James W Hoekstra, Cedric W Lefebvre, Bret A Nicks, David M Cline, Kim L Askew, David M Herrington, Gregory L Burke, Chadwick D Miller
OBJECTIVES: The HEART Pathway combines a decision aid and serial contemporary cardiac troponin I (cTnI) measures to achieve >99% sensitivity for major adverse cardiac events (MACE) at 30days and early discharge rates >20%. However, the impact of integrating high-sensitivity troponin (hs-cTn) measures into the HEART Pathway has yet to be determined. In this analysis we compare test characteristics of the HEART Pathway using hs-cTnI, hs-cTnT, or cTnI. DESIGN &METHODS: A secondary analysis of participants enrolled in the HEART Pathway RCT was conducted...
January 10, 2017: Clinical Biochemistry
https://www.readbyqxmd.com/read/28087298/the-utility-of-sex-hormone-binding-globulin-in-hypogonadism-and-infertile-males
#20
Joshua Ring, Charles Welliver, Mike Parenteau, Stephen Markwell, Robert E Brannigan, Tobias S Köhler
PURPOSE: We sought to determine what role SHBG played with male infertility patients. METHODS: Retrospective review of 168 males seen in a fertility clinic from 2012-2014, to investigate the accuracy of TT in the biochemical diagnosis of hypogonadism using cBT as the reference value. We used a multivariable analysis to assess SHBG as an independent predictor of infertility. RESULTS: Computations using cBT as a standard in the measurement of definitive biochemical hypogonadism (<156 ng/dL) revealed a sensitivity, specificity, PPV, and NPV respectively of 81%, 83%, 81%, and 82% in diagnosing hypogonadism with TT alone...
January 10, 2017: Journal of Urology
keyword
keyword
16189
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"