bluuebunny/crossref_metadata_2025_split huggingface dataset:
C-terminal truncated hepatitis B virus x protein is associated with metastasis and enhances invasiveness by c-jun/matrix metalloproteinase protein 10 activation in hepatocellular carcinoma
Authors: Sze Karen M.F. , Chu Glanice K.Y. , Lee Joyce M.F. , Ng Irene O.L. 
Published: July 2012

Abstract
Random integration of hepatitis B virus (HBV) DNA into the host genome is frequent in human hepatocellular carcinoma (HCC) and this leads to truncation of the HBV DNA, particularly at the C-terminal end of the HBV X protein (HBx). In this study, we investigated the frequency of this natural C-terminal truncation of HBx in human HCCs and its functional significance. In 50 HBV-positive patients with HCC, full-length HBx was detected in all nontumorous livers. However, full-length HBx was found in only 27 (54%) of the HCC tumors, whereas natural carboxylic acid (COOH)-truncated HBx was found in the remaining 23 (46%) tumors. Upon clinicopathological analysis, the presence of natural COOH-truncated HBx significantly correlated with the presence of venous invasion, a hallmark of metastasis (P = 0.005). Inducible stable expression of the COOH-truncated HBx protein (with 24 amino acids truncated at the C-terminal end) enhanced the cell-invasive ability of HepG2 cells, as compared to full-length HBx, using the Matrigel cell-invasion assay. It also resulted in increased C-Jun transcriptional activity and enhanced transcription of matrix metalloproteinase 10 (MMP10), whereas activation of the MMP10 promoter by COOH-truncated HBx was abolished when the activator protein 1–binding sites on the MMP10 promoter were mutated. Furthermore, silencing of MMP10 by short interfering RNA in HBxΔC1-expressing HepG2 cells resulted in significant reduction of cell invasiveness. Conclusions: Our data suggest that COOH truncation of HBx, particularly with 24 amino acids truncated at the C-terminal end, plays a role in enhancing cell invasiveness and metastasis in HCC by activating MMP10 through C-Jun. (Hepatology 2013)
Scavenger receptor a restrains T-cell activation and protects against concanavalin A-induced hepatic injury
Authors: Zuo Daming , Yu Xiaofei , Guo Chunqing , Wang Hongxia , Qian Jie , Yi Huanfa , Lu Xiao , Lv Zhi-Ping , Subjeck John R. , Zhou Huiping , Sanyal Arun J. , Chen Zhengliang , Wang Xiang-Yang 
Published: July 2012

Abstract
Negative feedback immune mechanisms are essential for maintenance of hepatic homeostasis and prevention of immune-mediated liver injury. We show here that scavenger receptor A (SRA/CD204), a pattern recognition molecule, is highly up-regulated in the livers of patients with autoimmune or viral hepatitis, and of mice during concanavalin A (Con A)-induced hepatitis (CIH). Strikingly, genetic SRA ablation strongly sensitizes mice to Con A-induced liver injury. SRA loss, increased mortality and liver pathology correlate with excessive production of IFN-γ and heightened activation of T cells. Increased liver expression of SRA primarily occurs in mobilized hepatic myeloid cells during CIH, including CD11b+Gr-1+ cells. Mechanistic studies establish that SRA on these cells functions as a negative regulator limiting T-cell activity and cytokine production. SRA-mediated protection from CIH is further validated by adoptive transfer of SRA+ hepatic mononuclear cells or administration of a lentivirus-expressing SRA, which effectively ameliorates Con A-induced hepatic injury. Also, CIH and clinical hepatitis are associated with increased levels of soluble SRA. This soluble SRA displays a direct T-cell inhibitory effect and is capable of mitigating Con A-induced liver pathology. Conclusion: Our findings demonstrate an unexpected role of SRA in attenuation of Con A-induced, T-cell-mediated hepatic injury. We propose that SRA serves as an important negative feedback mechanism in liver immune homeostasis, and may be exploited for therapeutic treatment of inflammatory liver diseases. (Hepatology 2013)
Retracted: The Relationship between Personality Traits and Sales Force Automation Usage: A Review of Methodology
Authors: Chen Cheng‐Wu , Yang Han‐Chung , Chen Chia‐Hung , Tseng Chun‐Pin , Lee King‐Ling 
Published: July 2012

AbstractIn recent decades, pharmaceutical companies have been facing increasing difficulties in sustaining sales growth due to tight market competition (off‐patents, pricing erosion, and generics substitution). Pharmaceutical companies are desperately seeking ways to sustain and optimize their sales coverage and sales volume in the middle and long term. In such unpromising circumstances, one of the few options that comes to mind is customer relationship management (CRM). This study specifically looks at the “utilization‐individual impact” link. In particular, this study aims to identify the personality type of sales representative most closely linked with individual usage of sales forces automation systems in the pharmaceutical industry in Taiwan. © 2012 Wiley Periodicals, Inc.
Overexpression of HnRNP A1 promotes tumor invasion through regulating CD44v6 and indicates poor prognosis for hepatocellular carcinoma
Authors: Zhou Zheng‐Jun , Dai Zhi , Zhou Shao‐Lai , Fu Xiu‐Tao , Zhao Yi‐Ming , Shi Ying‐Hong , Zhou Jian , Fan Jia 
Published: July 2012

AbstractHeterogeneous ribonucleoprotein (hnRNP) A1 is a member of the A/B subfamily of ubiquitously expressed hnRNPs, which have a wide variety of functions in gene expression and signal transduction. To investigate the biological function and clinical significance of hnRNP A1 in hepatocellular carcinoma (HCC), we measured hnRNP A1 expression in four HCC cell lines and two independent cohorts of HCC patients. We found that hnRNP A1 was overexpressed in the highly metastatic HCC cell lines and in tumor tissues of patients with recurrent HCC. Knockdown of hnRNP A1 in highly metastatic HCC cells caused a significant decrease in cell invasion, while upregulation of hnRNP A1 in poorly metastatic HCC cells led to a significant increase in their invasive capacity. We found that this effect may occur through the regulation of CD44v6 expression by hnRNP A1 in HCC cells. Both quantitative reverse transcription‐polymerase chain reaction (qRT‐RCR) and immunohistochemistry revealed that hnRNP A1 was upregulated in HCC tissues and coincided with overexpression of CD44v6. HCC patients with high hnRNP A1 tended to have higher levels of CD44v6, shorter overall survival (OS) and higher rates of tumor recurrence. Multivariate analyses revealed that hnRNP A1 alone or in combination with CD44v6 were independent prognostic indicators for OS and time to recurrence and have potential as therapeutic targets. In conclusion, overexpression of hnRNP A1 promotes HCC invasion by regulating the level of CD44v6 and indicates a poor prognosis for HCC patients after curative resection.
Biodegradable composites with aligned hydroxyapatite nanoneedles
Authors: Sun Shih‐Po , Wei Mei , Olson James R. , Shaw Montgomery T. 
Published: July 2012

AbstractWe prepared an anisotropic bone graft composite to mimic the hierarchical structure of the natural bone in which aligned hydroxyapatite (HA) nanocrystals deposit along collagen fibers. To approach the modulus and strength of the bone, we incorporated synthesized HA nanoneedles and melt drawn poly(L‐lactic acid) fibers in our composite as reinforcing components. Their preferred orientation was induced via a modified pultrusion process. The HA orientation distribution was examined using wide angle X‐ray diffraction. Micromechanical Halpin–Tsai model predictions considering the amount, shape, and orientation distribution of HA were compared, favorably, with the experimental observations. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Understanding bioactivity and polarizability of hydroxyapatite doped with tungsten
Authors: Dhal Jharana , Fielding Gary , Bose Susmita , Bandyopadhyay Amit 
Published: July 2012

AbstractThis study investigates the use of hydroxyapatite (HAp) doped with hexavalent tungsten to improve its interaction with bone cells and to influence the polarizing capacity of HAp. Increases in dopant concentration increased the β‐TCP phases and decreased the HAp phases in sintered samples. Results of thermally stimulated depolarization current measurements suggested that doped HAp had stored fewer charge compared with pure HAp. However, the decrease in stored charge was related to fraction of HAp or β‐TCP phases present in sintered samples. Activation energy of dipole relaxation and stored charge was used to examine the mechanism of polarization. The charge stored in doped samples due to polarization was attributed to the migration of H+ ions in HAp phases and O2− or Ca2+ ions in β‐TCP phases. Hindrance of ion migration due to the presence of different phases appeared to lower charge storage ability in doped samples. In vitro study revealed an increase in bioactivity of doped HAp when compared with pure HAp. Polarization further improved the bioactivity of doped HAp. Results of our study provide evidence for the use of higher valent cations to improve biological performance of HAp ceramics. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Behavior of poly(glycerol sebacate) plugs in chronic tympanic membrane perforations
Authors: Sundback C. A. , McFadden J. , Hart A. , Kulig K. M. , Wieland A. M. , Pereira M. J. N. , Pomerantseva I. , Hartnick C. J. , Masiakos P. T. 
Published: July 2012

AbstractThe tympanic membrane (TM), separating the external and middle ear, consists of fibrous connective tissue sandwiched between epithelial layers. To treat chronic ear infections, tympanostomy drainage tubes are placed in surgically created holes in TMs which can become chronic perforations upon extrusion. Perforations are repaired using a variety of techniques, but are limited by morbidity, unsatisfactory closure rates, or minimal regeneration of the connective tissue. A more effective, minimally‐invasive therapy is necessary to enhance the perforation closure rate. Current research utilizing decellularized or alignate materials moderately enhance closure but the native TM architecture is not restored. Poly(glycerol sebacate) (PGS) is a biocompatible elastomer which supports cell migration and enzymatically degrades in contact with vascularized tissue. PGS spool‐shaped plugs were manufactured using a novel process. Using minimally invasive procedures, these elastomeric plugs were inserted into chronic chinchilla TM perforations. As previously reported, effective perforation closure occurred as both flange surfaces were covered by confluent cell layers; >90% of perforations were closed at 6‐week postimplantation. This unique in vivo environment has little vascularized tissue. Consequently, PGS degradation was minimal over 16‐week implantation, hindering regeneration of the TM fibrous connective tissue. PGS degradation must be enhanced to promote complete TM regeneration. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Dual functionalization of titanium with vascular endothelial growth factor and β‐defensin analog for potential application in keratoprosthesis
Authors: Tan Xiao Wei , Lakshminarayanan R. , Liu Shou Ping , Goh Eunice , Tan Donald , Beuerman Roger W. , Mehta Jodhbir S. 
Published: July 2012

AbstractFunctionalization of material surfaces can improve their biointegration and bactericidal effect. To expand the biomedical applications of titanium in artificial cornea implantation surgery, titanium alloy substrates were coated with polydopamine and dual bound with recombinant vascular endothelial growth factor (VEGF) and anti‐microbial peptide (AMP), SESB2V. Successful chemical binding was assessed with attenuated total reflectance‐Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy. Coating thickness was assessed by atomic force microscopy. Cellular studies revealed that the functionalized substrates displayed the abilities to enhance primary human corneal fibroblast adhesion, proliferation, and viability. Angiogenesis assay with human mesenchymal stem cells was used to verify the biological functions of immobilized VEGF while bactericidal assay was evaluated for the anti‐microbial activities of immobilized SESB2V peptide. We found that the titanium surface that was sequentially functionalized with VEGF and SESB2V had enhanced fibroblast proliferation and anti‐microbial properties. The incorporation of such peptides into an artificial cornea implant is important for implant‐tissue integration and wound healing. This may improve implant integration and reduce the risk of device infection following artificial cornea implantation. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Design of Angiotensin‐converting Enzyme 2 (ACE2) Inhibitors by Virtual Lead Optimization and Screening
Authors: Torres Juan E. , Baldiris Rosa , Vivas‐Reyes Ricardo 
Published: July 2012

AbstractA group of presumed drug‐like molecules that possess high in silico affinity for angiotensin‐converting enzyme 2 were computationally designed. This enzyme is a promising new target in both cardiorenal disease and some coronavirus infections. A set of substrate analogous molecules were optimized by means of the LeapFrog module of the SYBYL package. Later, Molinspiration and Molsoft were used for screening out the compounds with low oral bioavailability. Similarly, OSIRIS was used for screening out the compounds having serious side effects. At the end of several stages of screening, seven candidates to anti‐viral drugs fulfiling all the evaluated criteria were obtained. They are amenable for future studies in vitro and in vivo. These designed ligands were finally evaluated by Quantitative Structure Activity Relationship studies. 21 molecules were used to carry out the qsar models. Fom these four molecules were taken as external sets yielding models with q2 = 0.652 and r2 = 0.962 values.
Nanoporous Carbon as Anode Material of High Rate Capability for Lithium Ion Batteries
Authors: Liu Li‐Li , Tian Shu , Zhu Yu‐Song , Tang Wei , Li Lin‐Lin , Wu Yu‐Ping 
Published: July 2012

AbstractA nanoporous carbon was prepared by calcining a mixture of nano‐CaCO3 and phenolic resin followed by an etching process to remove the remained impurities. It was characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and charge–discharge measurement. With a pore‐distribution concentrated around 50 nm, the product presents a BET surface area of 543 m2/g. When used as an anode material for lithium ion battery, the nanoporous carbon exhibits good rate capability and cycling performance.
An Electrochemical Approach for Estimation of Intrinsic Active Area and Activation of Pt/C Nano‐catalysts
Authors: Pan Chun‐Jern , Su Wei‐Nien , Kumar Sakkarapalayam Murugesan Senthil , Al Andra Cun Cun , Yang Shaw‐Jing , Chen Hung‐Yi , Hwang Bing Joe 
Published: July 2012

AbstractA methodology has been developed for the estimation of intrinsic active area of Pt/C nano‐catalysts which is crucial for the evaluation of catalyst's utilization in a membrane‐electrode‐assembly (MEA). The evaluation was carried out by employing the H‐UPD and CO stripping methods for both a thin porous Pt/C‐Nafion film coated on a glassy carbon disk and a carbon paper electrode. The results demonstrate that the measured values of intrinsic active area (i.e., the extents of utilization) of Pt/C in Nafion ionomer films are identical at both glassy carbon (GC) and carbon paper surfaces from 2 to 330 μg‐Pt/cm2 loading. However, the measured active area is strongly dependent on the electrode support for the loadings greater than 330 μg‐Pt /cm2 where the carbon paper electrodes show much higher active areas. Three different pre‐activation methods have been adopted to activate all the Pt sites in the catalyst layer namely potential cycling and constant potential treatment at an applied potential of 0 or 1.2 V (RHE). These results demonstrate the necessity of such a simple and convenient pre‐operation activation treatment for Pt/C catalysts in MEA to assess their intrinsic active area towards the electrochemical reactions.
Accuracy and precision of vessel area assessment: Manual versus automatic lumen delineation based on full‐width at half‐maximum
Authors: Merkx Maarten A.G. , Bescós Javier Oliván , Geerts Liesbeth , Bosboom E. Mariëlle H. , van de Vosse Frans N. , Breeuwer Marcel 
Published: July 2012

AbstractPurpose:To evaluate the accuracy and precision of manual and automatic blood vessel diameter measurements, a quantitative comparison was conducted, using both phantom and clinical 3D magnetic resonance angiography (MRA) data. Since diameters are often manually measured, which likely is influenced by operator dependency, automatic lumen delineation, based on the full‐width at half‐maximum (FWHM), could improve these measurements.Materials and Methods:Manual and automatic diameter assessments were compared, using MRA data from a vascular phantom (geometry obtained with μCT) and clinical MRA data. The diameters were manually assessed by 15 MRA experts, using both caliper and contour tools. To translate the experimental results to clinical practice, the precision obtained using phantom data was compared to the precision obtained with clinical data.Results:A diameter error <10% was obtained with resolutions above 2, 3, and 5 pixels/diameter for the automatic FWHM, contour, and caliper methods, respectively. Using phantom data, precision of the manual methods was low (error >20%), even at high resolutions, while precision for the automatic method was high (error <3%) when using more than 2 pixels/diameter. A similar trend was found with clinical data.Conclusion:The results obtained clearly demonstrate improvement in the accuracy and precision of vessel diameter measurements with use of the automatic FWHM‐based method. J. Magn. Reson. Imaging 2012;36:1186–1193. © 2012 Wiley Periodicals, Inc.
Accelerated 3D MERGE carotid imaging using compressed sensing with a hidden markov tree model
Authors: Makhijani Mahender K. , Balu Niranjan , Yamada Kiyofumi , Yuan Chun , Nayak Krishna S. 
Published: July 2012

AbstractPurpose:To determine the potential for accelerated 3D carotid magnetic resonance imaging (MRI) using wavelet based compressed sensing (CS) with a hidden Markov tree (HMT) model.Materials and Methods:We retrospectively applied HMT model‐based CS and conventional CS to 3D carotid MRI data with 0.7 mm isotropic resolution from six subjects with known carotid stenosis (12 carotids). We applied a wavelet‐tree model learned from a training database of carotid images to improve CS reconstruction. Quantitative endpoints such as lumen area, wall area, mean and maximum wall thickness, plaque calcification, and necrotic core area were measured and compared using Bland–Altman analysis along with image quality.Results:Rate‐4.5 acceleration with HMT model‐based CS provided image quality comparable to that of rate‐3 acceleration with conventional CS and fully sampled reference reconstructions. Morphological measurements made on rate‐4.5 HMT model‐based CS reconstructions were in good agreement with measurements made on fully sampled reference images. There was no significant bias or correlation between mean and difference of measurements when comparing rate 4.5 HMT model‐based CS with fully sampled reference images.Conclusion:HMT model‐based CS can potentially be used to accelerate clinical carotid MRI by a factor of 4.5 without impacting diagnostic quality or quantitative endpoints. J. Magn. Reson. Imaging 2012;36:1194–1202. © 2012 Wiley Periodicals, Inc.
MR angiography of carotid artery aneurysms in a porcine model at 3 tesla: Comparison of two different macrocyclic gadolinium chelates and of dynamic and conventional techniques
Authors: Wuesten Oliver , Morelli John N. , Miller Matthew W. , Tuzun Egemen , Lenox Mark W. , Fossum Theresa W. , Trelles Miguel , Cotes Claudia , Krombach Gabriele A. , Runge Val M. 
Published: July 2012

AbstractPurpose:To evaluate the differences in image quality of two macrocyclic gadolinium‐based contrast agents, gadobutrol and gadoterate meglumine, using time‐resolved, contrast‐enhanced MR angiography (CE‐MRA) in a porcine carotid artery aneurysm model and to compare image quality between dynamic and conventional, single acquisition CE‐MRA.Materials and Methods:Bilateral carotid aneurysms were created surgically in this Institutional Animal Care and Use Committee approved study. Dynamic CE‐MRA studies optimized for high temporal resolution were performed at 3 Tesla. Scans using equivalently dosed (on a per mmol basis) gadobutrol and gadoterate meglumine were compared qualitatively and quantitatively in terms of contrast‐to‐noise ratio (CNR). Higher spatial resolution dynamic and conventional CE‐MRA were also compared.Results:N = 16 aneurysms were assessed. Qualitative evaluation of dynamic CE‐MRA scans demonstrated a preference for gadobutrol over gadoterate meglumine. Significantly higher aneurysm CNR was found with gadobutrol (133 ± 44) versus gadoterate meglumine, the latter at both equivalent and double injection rates (94 ± 35 and 102 ± 38). In a blinded assessment, conventional CE‐MRA was preferred qualitatively when compared with dynamic CE‐MRA. However, dynamic CE‐MRA was generally capable of providing diagnostic image quality.Conclusion:Gadobutrol is preferred to gadoterate meglumine for high temporal resolution dynamic CE‐MRA, a fact with important clinical implications for low dose CE‐MRA protocols in patients at risk for nephrogenic systemic fibrosis. Conventional high resolution CE‐MRA provides superior image quality when compared with dynamic CE‐MRA. J. Magn. Reson. Imaging 2012;36:1203–1212. © 2012 Wiley Periodicals, Inc.
MR proton spectroscopy for myocardial lipid deposition quantification: A quantitative comparison between 1.5T and 3T
Authors: Venkatesh Bharath Ambale , Lima Joao A.C. , Bluemke David A. , Lai Shenghan , Steenbergen Charles , Liu Chia‐Ying 
Published: July 2012

AbstractPurpose:To evaluate 3T magnetic resonance spectroscopy (MRS)‐derived myocardial fat‐signal fractions in comparison with those from 1.5T MRS.Materials and Methods:We conducted phantom, ex vivo and in vivo myocardial specimen evaluations at both 1.5T and 3T using 1H‐MRS. A phantom with nine fat‐water emulsions was constructed to assess the accuracy of the spectroscopy measurements. Ex vivo spectroscopy data were acquired in 70 segments from 21 autopsy heart slices. In vivo spectroscopy data were acquired in the interventricular septum from 22 human volunteers.Results:Phantom experiments demonstrated that 1.5T and 3T measurements were highly correlated with the reference values (r = 0.78, P < 0.05). The ex vivo and in vivo experiments demonstrated an increase in signal‐to‐noise ratio (SNR) of 45 ± 73% and 76 ± 72% at 3T compared to 1.5T (P < 0.05). The mean fat‐signal fraction was similar at 3T and 1.5T (1.11 ± 1.18 vs. 1.00 ± 1.09, respectively, P = NS) in ex vivo studies but were significantly different in the in vivo studies (2.47 ± 1.46 vs. 1.56 ± 1.34, P < 0.05). The fat‐signal fractions from 3T and 1.5T correlated fairly well in all experiments.Conclusion:3T MRS has significantly greater SNR and could potentially be more accurate as compared to 1.5T for quantification of myocardial fat fraction in in vivo studies. J. Magn. Reson. Imaging 2012;36:1222–1230. © 2012 Wiley Periodicals, Inc.