bluuebunny/crossref_metadata_2025_split huggingface dataset:
Image segmentation model based on adaptive adjustment of global and local information
Authors: Wang Xianghai , Song Ruoxi , Zhang Chong , Li Chang , Fang Lingling 
Published: August 2016

ABSTRACTIn this article, an adaptive mixture model for image segmentation that synthesizes both global information and local information using a new adaptive balance function has been proposed. Given the variety of possible image characteristics that may have to be processed, the proposed model can adaptively adjust the weighting to drive curve evolution trends and states. In this way, the intensity information of weak boundaries and complex backgrounds can be extracted more precisely, thus enabling the model to produce better results for low‐contrast images and complex structures. In addition, a Gaussian filtering process has been added to the model to smooth and standardize the level set function, and a parameter has been introduced to speed up the curve evolution. A penalty term is also used to eliminate the need for complex re‐initialization procedures. Experimental results for various kinds of images efficiently demonstrate the good performance of the proposed model in terms of both speed and accuracy. © 2016
Wiley Periodicals, Inc. Int J Imaging Syst Technol, 26, 179–187, 2016
Earlier detection of cancer regions from MR image features and SVM classifiers
Authors: Rajaguru Harikumar , Ganesan Karthick , Bojan Vinoth Kumar 
Published: August 2016

ABSTRACTIn this article, we examine the use of several segmentation algorithms for medical image classification. This work detects the cancer region from magnetic resonance (MR) images in earlier stage. This is accomplished in three stages. In first stage, four kinds of region‐based segmentation techniques are used such asK‐means clustering algorithm, expectation–maximization algorithm, partial swarm optimization algorithm, and fuzzy c‐means algorithm. In second stage, 18 texture features are extracting using gray level co‐occurrence matrix (GLCM). In stage three, classification is based on multi‐class support vector machine (SVM) classifier. Finally, the performance analysis of SVM classifier is analyzed using the four types of segmentation algorithm for a group of 200 patients (32—Glioma, 32—Meningioma, 44—Metastasis, 8—Astrocytoma, 72—Normal). The experimental results indicate that EM is an efficient segmentation method with 100% accuracy. In SVM, quadratic and RBF (σ = 0.5) kernel methods provide the highest classification accuracy compared to all other SVM kernel methods. © 2016 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 26, 196–208, 2016
Interaction‐tailored cell aggregates in alginate hydrogels for enhanced chondrogenic differentiation
Authors: Park Honghyun , Kim Doyun , Lee Kuen Yong 
Published: August 2016

AbstractControlling cell–matrix interactions is critical when transferring cells into the body using a scaffold, which can be elaborately tailored to successfully engineer the desired tissue. In this study, ATDC5 cells were encapsulated within alginate hydrogels and their chondrogenic differentiation was investigated in vitro. Cell–matrix interactions were introduced using RGD peptides, which improved the viability of encapsulated cells and enhanced the formation of condensed structures similar to a chondrogenic nodule. When N‐cadherin of ATDC5 cells was blocked, the encapsulated cells did not form an aggregate, and chondrogenic differentiation could not be induced. Preformed cell aggregates with defined cell numbers in RGD‐modified alginate gels retained adequate N‐cadherin‐mediated cell–cell interactions and increased chondrogenic marker gene expression, compared with the homogeneously dispersed cells in the gels. This approach may be useful to promote chondrogenesis with relatively few cells if they are encapsulated into a scaffold as a form of aggregates. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 42–50, 2017.
In vitro cyclic compressive loads potentiate early osteogenic events in engineered bone tissue
Authors: Ravichandran Akhilandeshwari , Lim Jing , Chong Mark Seow Khoon , Wen Feng , Liu Yuchun , Pillay Yaesshna T. , Chan Jerry K. Y. , Teoh Swee‐Hin 
Published: August 2016

AbstractApplication of dynamic mechanical loads on bone and bone explants has been reported to enhance osteogenesis and mineralization. To date, published studies have incorporated a range of cyclic strains on 3D scaffolds and platforms to demonstrate the effect of mechanical loading on osteogenesis. However, most of the loading parameters used in these studies do not emulate the in vivo loading conditions. In addition, the scaffolds/platforms are not representative of the native osteoinductive environment of bone tissue and hence may not be entirely accurate to study the in vivo mechanical loading. We hypothesized that biomimicry of physiological loading will potentiate accelerated osteogenesis in bone grafts. In this study, we present a compression bioreactor system that applies cyclic compression to cellular grafts in a controlled manner. Polycaprolactone‐β Tricalcium Phosphate (PCL‐TCP) scaffolds seeded with Mesenchymal Stem Cells (MSC) were cyclically compressed in bioreactor for a period of 4 weeks at 1 Hz and physiological strain value of 0.22% for 4 h per day. Gene expression studies revealed increased expressions of osteogenesis‐related genes (Osteonectin and COL1A1) on day 7 of cyclic loading group relative to its static controls. Cyclic compression resulted in a 3.76‐fold increase in the activity of Alkaline Phosphatase (ALP) on day 14 when compared to its static group (p < 0.001). In addition, calcium deposition of cyclic loading group was found to attain saturation on day 14 (1.96 fold higher than its static scaffolds). The results suggested that cyclic, physiological compression of stem cell‐seeded scaffolds generated highly mineralized bone grafts. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2366–2375, 2017.
Treatment of biliary tract stones after gastrectomy in the era of laparoscopic cholecystectomy
Authors: Hashimoto Masaji , Imamura Tsunao , Tamura Tetsuo , Koyama Rikako , Koizumi Yuko , Makuuchi Mikio , Matsuda Masamichi , Watanabe Goro 
Published: August 2016

AbstractBackgroundThe incidence of biliary tract stones has widely been reported to be high after gastrectomy. Treatment of biliary tract stones in post‐gastrectomy patients was examined retrospectively, particularly minimally invasive therapy with laparoscopic cholecystectomy for gallbladder stones and endoscopic bile duct lithotomy for common bile duct stones.MethodsTreatment of 122 post‐gastrectomy patients with biliary tract stones was examined retrospectively from 1995 to April 2015.ResultsSymptomatic biliary tract stones were found in 3.7% of post‐gastrectomy patients. The frequency of bile duct stones was higher in post‐gastrectomy patients with gallbladder stones (44%) than in the nongastrectomy patients (11%). Laparoscopic cholecystectomy was carried out in 84% of the patients with gallbladder stones. Endoscopic bile duct lithotomy was feasible in 89% of patients with common bile duct stones.ConclusionsLaparoscopic cholecystectomy was feasible for removing gallbladder stones after gastrectomy. Endoscopic bile duct lithotomy followed by laparoscopic cholecystectomy was a good option for patients in whom endoscopic intervention could be performed. On the other hand, choledochoenterostomy could be a good option for patients in whom endoscopic bile duct lithotomy cannot be performed, particularly considering the risk of recurrent bile duct stones.
Fat‐suppressed T2 mapping of femoral cartilage in the porcine knee joint: A comparison with conventional T2 mapping
Authors: Ryu Young Jin , Hong Sung Hwan , Kim Hyeonjin , Choi Ja‐Young , Yoo Hye Jin , Kang Yusuhn , Park Sang Joon , Kang Heung Sik 
Published: August 2016

PurposeTo investigate the effect of fat suppression on T2 mapping of the articular cartilage in the porcine knee joint using magnetic resonance imaging (MRI).Materials and MethodsEleven porcine knee joints were harvested en bloc with intact capsules. We performed T2 mapping of the articular cartilage in the medial femoral condyle at 3T either with (fat‐suppressed T2 mapping) or without (conventional T2 mapping) fat suppression in the sagittal plane under two frequency‐encoding directions: from superior to inferior (SI) and inferior to superior (IS). Two observers measured the T2 values of the medial femoral condyle cartilage in four regions: in the anterior oblique, central horizontal, posterior oblique, and posterior vertical portions. We evaluated reproducibility of the fat‐suppressed and conventional T2 mapping by changing the frequency‐encoding direction.ResultsThe mean T2 values of fat‐suppressed T2 mapping were significantly lower than those of conventional T2 mapping for five of eight comparisons (P < 0.017). The mean T2 values between fat‐suppressed T2‐SI and fat‐suppressed T2‐IS did not differ significantly in any region (P = 0.077–0.873). However, the mean T2 values of conventional T2‐SI were significantly lower compared with conventional T2‐IS in three of the regions (P < 0.05). The intraclass correlation coefficient (ICC) between the two fat‐suppressed T2 maps was higher than the ICC between the two conventional T2 maps (0.276–0.800 vs. –0.032–0.455) for three regions.ConclusionCompared with conventional T2 mapping, fat‐suppressed T2 mapping provides lower T2 values of the articular cartilage and more reproducible results for the porcine knee joint.Level of Evidence: 2J. Magn. Reson. Imaging 2017;45:1076–1081
Diagnostic accuracy of intracellular uptake rates calculated using dynamic Gd‐EOB‐DTPA‐enhanced MRI for hepatic fibrosis stage
Authors: Juluru Krishna , Talal Andrew H. , Yantiss Rhonda K. , Spincemaille Pascal , Weidman Elizabeth K. , Giambrone Ashley E. , Jalili Sadaf , Sourbron Steven P. , Dyke Jonathan P. 
Published: August 2016

PurposeTo assess the diagnostic accuracy of intracellular uptake rates (Ki), and other quantitative pharmacokinetic (PK) parameters, for hepatic fibrosis stage; to compare this accuracy with a previously published semiquantitative metric, contrast enhancement index (CEI); and to assess variability of these parameters between liver regions.Materials and MethodsThis was a case–control study design. Dynamic Gd‐EOB‐DTPA‐enhanced 1.5T magnetic resonance imaging (MRI) was performed prospectively in 22 subjects with varying known stages of hepatic fibrosis. PK parameters and CEI were derived from the whole livers and from three fixed regions of interest (ROIs) in all subjects. Spearman rank correlation coefficients were computed to assess the relationship between fibrosis stages and each parameter. Receiver operating characteristic (ROC) curves were constructed to discriminate severe fibrosis (stages 3–4) from nonsevere fibrosis (stages 0–2). The coefficient of variation (CV) was calculated to assess variability in parameters between ROIs.ResultsKi and fibrosis stage were significantly correlated (R = –0.55, 95% confidence interval [CI] [–0.79, –0.14], P = 0.01). Area under ROC curve (AUC) in distinguishing severe from nonsevere fibrosis for Ki was 0.84 (95% CI [0.65,1.00]), and for CEI was 0.64 (95% CI [0.39, 0.89]) (P = 0.0248). CV for Ki and CEI were 33.4 and 5.8, respectively. The only other parameter in the PK model having significant correlation with fibrosis stage was absolute arterial blood flow (Fa) (R = –0.48, 95% CI [−0.75,−0.05], P = 0.03).ConclusionHepatocyte intracellular uptake rate, Ki, derived from dynamic contrast‐enhanced MRI, correlates with fibrosis stage and may contribute to a noninvasive biomarker of hepatic fibrosis.Level of Evidence: 2J. Magn. Reson. Imaging 2017;45:1177–1185
High phenolics Rutgers Scarlet Lettuce improves glucose metabolism in high fat diet‐induced obese mice
Authors: Cheng Diana M. , Roopchand Diana E. , Poulev Alexander , Kuhn Peter , Armas Isabel , Johnson William D. , Oren Andrew , Ribnicky David , Zelzion Ehud , Bhattacharya Debashish , Raskin Ilya 
Published: August 2016

ScopeThe ability of high phenolic Rutgers Scarlet Lettuce (RSL) to attenuate metabolic syndrome and gut dysbiosis was studied in very high fat diet (VHFD)‐fed mice. Phenolic absorption was assessed in vivo and in a gastrointestinal tract model.Methods and resultsMice were fed VHFD, VHFD supplemented with RSL (RSL‐VHFD) or store‐purchased green lettuce (GL‐VHFD), or low‐fat diet (LFD) for 13 weeks. Compared to VHFD or GL‐VHFD‐fed groups, RSL‐VHFD group showed significantly improved oral glucose tolerance (p<0.05). Comparison of VHFD, RSL‐VHFD, and GL‐VHFD groups revealed no significant differences with respect to insulin tolerance, hepatic lipids, body weight gain, fat mass, plasma glucose, triglycerides, free fatty acid, and lipopolysaccharide levels, as well as relative abundances of major bacterial phyla from 16S rDNA amplicon data sequences (from fecal and cecal samples). However, RSL and GL‐supplementation increased abundance of several taxa involved in plant polysaccharide degradation/fermentation. RSL phenolics chlorogenic acid, quercetin‐3‐glucoside, and quercetin‐malonyl‐glucoside were bioaccessible in the TIM‐1 digestion model, but had relatively low recovery.ConclusionsRSL phenolics contributed to attenuation of post‐prandial hyperglycemia. Changes in gut microbiota were likely due to microbiota accessible carbohydrates in RSL and GL rather than RSL phenolics, which may be metabolized, absorbed, or degraded before reaching the colon.
Characterizing brain tissue by assessment of the distribution of anisotropic microstructural environments in diffusion‐compartment imaging (DIAMOND)
Authors: Scherrer Benoit , Schwartzman Armin , Taquet Maxime , Sahin Mustafa , Prabhu Sanjay P. , Warfield Simon K. 
Published: August 2016

PurposeTo develop a statistical model for the tridimensional diffusion MRI signal at each voxel that describes the signal arising from each tissue compartment in each voxel.Theory and MethodsIn prior work, a statistical model of the apparent diffusion coefficient was shown to well‐characterize the diffusivity and heterogeneity of the mono‐directional diffusion MRI signal. However, this model was unable to characterize the three‐dimensional anisotropic diffusion observed in the brain. We introduce a new model that extends the statistical distribution representation to be fully tridimensional, in which apparent diffusion coefficients are extended to be diffusion tensors. The set of compartments present at a voxel is modeled by a finite sum of unimodal continuous distributions of diffusion tensors. Each distribution provides measures of each compartment microstructural diffusivity and heterogeneity.ResultsThe ability to estimate the tridimensional diffusivity and heterogeneity of multiple fascicles and of free diffusion is demonstrated.ConclusionOur novel tissue model allows for the characterization of the intra‐voxel orientational heterogeneity, a prerequisite for accurate tractography while also characterizing the overall tridimensional diffusivity and heterogeneity of each tissue compartment. The model parameters can be estimated from short duration acquisitions. The diffusivity and heterogeneity microstructural parameters may provide novel indicator of the presence of disease or injury. Magn Reson Med 76:963–977, 2016. © 2015 Wiley Periodicals, Inc.
Weighted norms in subspace‐based methods for time series analysis
Authors: Gillard J. W. , Zhigljavsky A. A. 
Published: August 2016

SummaryMany modern approaches of time series analysis belong to the class of methods based on approximating high‐dimensional spaces by low‐dimensional subspaces. A typical method would embed a given time series into a structured matrix and find a low‐dimensional approximation to this structured matrix. The purpose of this paper is twofold: (i) to establish a correspondence between a class of SVD‐compatible matrix norms on the space of Hankel matrices and weighted vector norms (and provide methods to construct this correspondence) and (ii) to motivate the importance of this for problems in time series analysis. Examples are provided to demonstrate the merits of judiciously selecting weights on imputing missing data and forecasting in time series. Copyright © 2016 John Wiley & Sons, Ltd.
Confounding of the association between statins and Parkinson disease: systematic review and meta‐analysis
Authors: Bykov Katsiaryna , Yoshida Kazuki , Weisskopf Marc G. , Gagne Joshua J. 
Published: August 2016

AbstractPurposeBoth statins and higher serum cholesterol have been reported to reduce to risk of Parkinson Disease (PD). Given the importance of adjusting for cholesterol levels when evaluating the effect of statins, we assessed whether the protective effect of statins would remain when adjustment for cholesterol is performed.MethodsWe conducted a systematic review of epidemiologic studies that reported quantitative estimates of the association between statins and incident PD and were published through February 2016. Random‐effects meta‐analysis was used to assess the effect of statins on PD separately among the studies that adjusted for either cholesterol or hyperlipidemia and studies that did not.ResultsTen eligible studies that evaluated the use of statins and incident PD were identified. Among the six studies that did not adjust for cholesterol, a protective effect of statins was observed (relative risk 0.75; 95% confidence intervals (CI) 0.60 to 0.92). Excluding studies with possible bias because of reverse causation or stratifying on study design did not affect the results. No protective effect was observed among the four studies that adjusted for either cholesterol of hyperlipidemia (relative risk 0.91; 95%CI 0.68 to 1.22). The effect estimate for studies that adjusted for cholesterol was 1.04 (95%CI 0.68 to 1.59) when a study with immortal time bias was excluded.ConclusionsThe apparent protective effect of statins on risk of PD is at least partially explained by confounding by statin indication. Immortal time bias and healthy user effects also could have contributed to biased results. Copyright © 2016 John Wiley & Sons, Ltd.
How valid are IMS DA summary statistics of children's vaccination status?
Authors: El‐Turki Aisha , Long Paul , Wong Ian CK , Smith Helen 
Published: August 2016

AbstractPurposeAccurate recording of immunization status is essential for the evaluation of any immunization programme. In September 2006, 7‐valent pneumococcal conjugate vaccination (PCV7) was introduced into the UK's routine childhood immunization programme. This study validated the PCV7 immunization status of children aged 2 years recorded in the IMS Disease Analyses (DA) database.MethodsThe PCV7 vaccination uptake rate for children born in 2008 in the IMS DA database was calculated. A sample of 173 of the 2497 children not recorded as vaccinated was identified, and a questionnaire was sent to each of their general practitioners to ascertain the child's true PCV7 vaccination status.ResultsIn the IMS DA data of 15 237 children born in 2008, 12 740 (83.6%) had a vaccination record of PCV7. One‐hundred and eleven of the 167 questionnaires sent to the child's general practitioners were returned, giving an adjusted response rate of 111/167 (66.5%). Based on the general practitioners' responses, 71 (64%) of these children were fully vaccinated according to their general practitioner's records making the revised estimated vaccination rate for this cohort 94.1%ConclusionThis validation study has shown that caution is needed if using historical IMS patient‐level data to analyse the effectiveness of PCV7 as there is a potential under‐recording of immunization leading to under representation of vaccination rates by approximately 10%. Copyright © 2016 John Wiley & Sons, Ltd.
Relative Risks for Lethal Prostate Cancer Based on Complete Family History of Prostate Cancer Death
Authors: Albright Frederick S. , Stephenson Robert A. , Agarwal Neeraj , Cannon‐Albright Lisa A. 
Published: August 2016

BACKGROUNDThere are few published familial relative risks (RR) for lethal prostate cancer. This study estimates RRs for lethal prostate cancer based on comprehensive family history data, with the goal of improving identification of those men at highest risk of dying from prostate cancer.METHODSWe used a population‐based genealogical resource linked to a statewide electronic SEER cancer registry and death certificates to estimate relative risks (RR) for death from prostate cancer based upon family history. Over 600,000 male probands were analyzed, representing a variety of family history constellations of lethal prostate cancer. RR estimates were based on the ratio of the observed to the expected number of lethal prostate cancer cases using internal rates.RESULTSRRs for lethal prostate cancer based on the number of affected first‐degree relatives (FDR) ranged from 2.49 (95% CI: 2.27, 2.73) for exactly 1 FDR to 5.30 (2.13, 10.93) for ≥3 affected FDRs. In an absence of affected FDRs, increased risk was also significant for increasing numbers of affected second‐degree or third degree relatives. Equivalent risks were observed for similar maternal and paternal family history.CONCLUSIONSThis study provides population‐based estimates of lethal prostate cancer risk based on lethal prostate cancer family history. Many family history constellations associated with two to greater than five times increased risk for lethal prostate cancer were identified. These lethal prostate cancer risk estimates hold potential for use in identification, screening, early diagnosis, and treatment of men at high risk for death from prostate cancer. Prostate77:41–48, 2017. © 2016 Wiley Periodicals, Inc.
Critical comparison of mass analyzers for forensic hair analysis by ambient ionization mass spectrometry
Authors: Duvivier Wilco F. , van Beek Teris A. , Nielen Michel W. F. 
Published: August 2016

RationaleRecently, several direct and/or ambient mass spectrometry (MS) approaches have been suggested for drugs of abuse imaging in hair. The use of mass spectrometers with insufficient selectivity could result in false‐positive measurements due to isobaric interferences. Different mass analyzers have been evaluated regarding their selectivity and sensitivity for the detection of Δ9‐tetrahydrocannabinol (THC) from intact hair samples using direct analysis in real time (DART) ionization.MethodsFour different mass analyzers, namely (1) an orbitrap, (2) a quadrupole orbitrap, (3) a triple quadrupole, and (4) a quadrupole time‐of‐flight (QTOF), were evaluated. Selectivity and sensitivity were assessed by analyzing secondary THC standard dilutions on stainless steel mesh screens and blank hair samples, and by the analysis of authentic cannabis user hair samples. Additionally, separation of isobaric ions by use of travelling wave ion mobility (TWIM) was investigated.ResultsThe use of a triple quadrupole instrument resulted in the highest sensitivity; however, transitions used for multiple reaction monitoring were only found to be specific when using high mass resolution product ion measurements. A mass resolution of at least 30,000 FWHM at m/z 315 was necessary to avoid overlap of THC with isobaric ions originating from the hair matrix. Even though selectivity was enhanced by use of TWIM, the QTOF instrument in resolution mode could not indisputably differentiate THC from endogenous isobaric ions in drug user hair samples.ConclusionsOnly the high resolution of the (quadrupole) orbitrap instruments and the QTOF instrument in high‐resolution mode distinguished THC in hair samples from endogenous isobaric interferences. As expected, enhanced selectivity compromises sensitivity and THC was only detectable in hair from heavy users. Copyright © 2016 John Wiley & Sons, Ltd.