bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mixed‐order interpolation for the Galerkin coarse‐grid approximations in algebraic multigrid solvers
Authors: Webster R. 
Published: April 2010

AbstractAn empirical investigation is made of AMG solver performance for the fully coupled set of Navier–Stokes equations. The investigation focuses on two different FV discretizations for the standard driven cavity test problem. One is a collocated vertex‐based discretization; the other is a cell‐centred staggered‐grid discretization. Both employ otherwise identical orthogonal Cartesian meshes. It is found that if mixed‐order interpolation is used in the construction of the Galerkin coarse‐grid approximation (CGA), a close‐to‐optimum mesh‐independent scaling of the AMG convergence is observed with similar convergence rates for both discretizations.If, on the other hand, an equal‐order interpolation is used, convergence rates are mesh‐dependent but the scaling differs in each case. For the collocated‐grid case, it depends both on the mesh size, h (or bandwidth Q∼h−1) and on the total number of grids, G, whereas for the staggered‐grid case it depends only on Q. Comparing the two characteristics reveals that the Q‐dependent parts are very similar; it is only in the G‐dependent convergence for the collocated‐grid case that they differ. This takes the form of stepped reductions in the AMG convergence rate (implying step reductions in the quality of the Galerkin CGA that correlate exactly with step increases in G).These findings reinforce previous evidence that, for optimum mesh‐independent performance, mixed‐order interpolations should be used in forming Galerkin CGAs for coupled Navier–Stokes problems. Copyright © 2010 John Wiley & Sons, Ltd.
Primary human osteoblast culture on 3D porous collagen‐hydroxyapatite scaffolds
Authors: Jones Gemma L. , Walton Robin , Czernuszka Jan , Griffiths Sarah L. , El Haj Alicia J. , Cartmell Sarah H. 
Published: April 2010

AbstractThere is a need in tissue‐engineering for 3D scaffolds that mimic the natural extracellular matrix of bone to enhance cell adhesion, proliferation, and differentiation. The scaffold is also required to be degradable. A highly porous scaffold has been developed to incorporate two of the extracellular components found in bone—collagen and hydroxyapatite (HA). The scaffold's collagen component is an afibrillar monomeric type I atelocollagen extracted from foetal calf's skin. This provided a novel environment for the inclusion of HA powder. Five hundred thousand primary human osteoblasts were seeded onto 4 mm cubed scaffolds that varied in ratio of HA to collagen. Weight ratios of 1:99, 25:75, 50:50, and 75:25 hydroxyapatite:collagen (HA:Collagen) were analysed. The scaffolds plus cells were cultured for 21 days. DNA assays and live/dead viability staining demonstrated that all of the scaffolds supported cell proliferation and viability. An alkaline phosphatase assay showed similar osteoblast phenotype maintenance on all of the 3D scaffolds analysed at 21 days. MicroCT analysis demonstrated an increase in total sample volume (correlating to increase in unmineralised matrix production). An even distribution of HA throughout the collagen matrix was observed using this technique. Also at 3 weeks, reductions in the percentage of the mineralised phase of the constructs were seen. These results indicate that each of the ratios of HA/collagen scaffolds have great potential for bone tissue engineering. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Fyn promotes phosphorylation of collapsin response mediator protein 1 at tyrosine 504, a novel, isoform‐specific regulatory site
Authors: Buel Gwen R. , Rush John , Ballif Bryan A. 
Published: April 2010

AbstractIn vertebrates the collapsin response mediator proteins (CRMPs) are encoded by five highly related genes. CRMPs are cytosolic phosphoproteins abundantly expressed in developing and mature mammalian brains. CRMPs are best understood as effectors of Semaphorin 3A signaling regulating growth cone collapse in migratory neurons. Phosphorylation in the carboxyl‐terminal regulatory domain of CRMPs by several serine/threonine kinases has been described. These phoshorylation events appear to function, at least in part, to disrupt the interaction of CRMPs with tubulin heterodimers. In a large‐scale phosphoproteomic analysis of murine brain, we recently identified a number of in vivo tyrosine phosphorylation sites on CRMP isoforms. Using biochemical approaches and quantitative mass spectrometry we demonstrate that one of these sites, CRMP1 tyrosine 504 (Y504), is a primary target of the Src family of tyrosine kinases (SFKs), specifically Fyn. Y504 is adjacent to CDK5 and GSK‐3β sites that regulate the interaction of CRMPs with tubulin. Although Y504 is highly conserved among vertebrate CRMP1 orthologs, a residue corresponding to Y504 is absent in CRMP isoforms 2–5. This suggests an isoform‐specific regulatory role for CRMP1 Y504 phosphorylation and may help explain the observation that CRMP1‐deficient mice exhibit neuronal migration defects not compensated for by CRMPs 2–5. J. Cell. Biochem. 111: 20–28, 2010. © 2010 Wiley‐Liss, Inc.
Antagonistic interplay between mechanical forces and glucocorticoids in bone: A tale of kinases
Authors: Bellido Teresita 
Published: April 2010

AbstractThe contrasting actions of mechanical forces and glucocorticoids (GC) on bone have been long recognized. However, the cellular and molecular mechanisms by which these stimuli impact the skeleton remain only partially known. Recent evidence gained from studies on bone cell apoptosis has revealed that mechanical forces and GC exhibit converse effects on osteocyte and osteoblast survival resulting from divergent actions on the focal adhesion kinases FAK and Pyk2, molecules that regulate integrin‐dependent interactions between bone cells and the extracellular matrix (ECM). This prospect reviews these findings and poses the possibility that similar opposing effects on kinase signaling are responsible for other actions of mechanical forces and GC on the skeleton, in particular on bone formation and the Wnt signaling pathway. J. Cell. Biochem. 111: 1–6, 2010. © 2010 Wiley‐Liss, Inc.
Transmembrane 4 L six family member 5 (TM4SF5) enhances migration and invasion of hepatocytes for effective metastasis
Authors: Lee Sin‐Ae , Kim Tae You , Kwak Tae Kyoung , Kim Hyeonjung , Kim Semi , Lee Hyo Jeong , Kim Sung‐Hoon , Park Ki Hun , Kim Hyun Jeong , Cho Moonjae , Lee Jung Weon 
Published: April 2010

AbstractOverexpression of transmembrane 4 L six family member 5 (TM4SF5), a four‐transmembrane L6 family member, causes aberrant cell proliferation and angiogenesis, but the roles of TM4SF5 in migration, invasion, and tumor metastasis remain unknown. Using in vitro hepatocarcinoma cells that ectopically or endogenously express TM4SF5 and in vivo mouse systems, roles of TM4SF5 in metastatic potentials were examined. We found that TM4SF5 expression facilitated migration, invadopodia formation, MMP activation, invasion, and eventually lung metastasis in nude mice, but suppression of TM4SF5 with its shRNA blocked the effects. Altogether, TM4SF5‐mediated migration and invasion suggest that TM4SF5 may be therapeutically targeted to deal with TM4SF5‐mediated hepatocellular cancers. J. Cell. Biochem. 111: 59–66, 2010. © 2010 Wiley‐Liss, Inc.
Localization of nucleophosmin in nuclear matrix and changes in its expression during the differentiation of human neuroblastoma induced by retinoic acid
Authors: Shi Song‐Lin , Liang Ying , Li Qi‐Fu , Liu Qing‐Rong , Jing Guang‐Jun , Wang San‐Ying , Zhang Xiu‐Yan , Wu Fu‐Yun 
Published: April 2010

AbstractIn this article, we selectively extracted the nuclear matrix and intermediate filament system of human neuroblastoma SK‐N‐SH cells pre‐ and post‐treated with retinoic acid (RA). The distribution of nucleophosmin (NPM) in the nuclear matrix and its colocalization with several products of related genes were investigated. Results from two‐dimensional gel electrophoresis and MALDI‐TOF showed that NPM was a component of the nuclear matrix and its expression in SK‐N‐SH cells post‐treated with RA was down‐regulated. Immunofluorescent microscopy observations further showed that NPM was localized in the nuclear matrix of SK‐N‐SH cells, and its expression level and distribution were altered after treatment with RA. The colocalization of NPM with c‐myc, c‐fos, p53, and Rb in SK‐N‐SH cells was observed under a laser scanning confocal microscope, but the colocalization region was changed by RA. Our results prove that NPM is a nuclear matrix protein, which is localized in nuclear matrix fibers. The colocalization of NPM with its related genes and oncogenes affect the differentiation of SK‐N‐SH cells. The expression of NPM and its distribution in the process of cell differentiation deserve more intensive investigation. J. Cell. Biochem. 111: 67–74, 2010. © 2010 Wiley‐Liss, Inc.
Basic FGF downregulates TSP50 expression via the ERK/Sp1 pathway
Authors: Wang Miao , Bao Yong‐Li , Wu Yin , Yu Chun‐Lei , Meng Xiang‐Ying , Huang Yan‐Xin , Sun Ying , Zheng Li‐Hua , Li Yu‐Xin 
Published: April 2010

AbstractPrevious studies demonstrated that the expression of testes‐specific protease 50 (TSP50) was increased in breast cancer cells and that overexpression of TSP50 can promote tumorigenesis. Thus, it is important to identify the regulatory mechanisms of TSP50 for tumor therapy. In this study, we elucidated the mechanism underlying TSP50 downregulation by basic fibroblast growth factor (bFGF). We used MDA‐MB‐231 and HEK293T cell lines to address this issue. RT‐PCR and promoter activity assays indicated that bFGF downregulates TSP50 expression via transcriptional activation. We next investigated the signaling pathway that mediated the effect of bFGF on TSP50 transcription, and identified that bFGF induced the phosphorylation of ERK and Sp1. An ERK inhibitor suppressed Sp1 phosphorylation and bFGF‐reduced TSP50 expression at the mRNA level. In addition, the dominant negative (DN) mutants of ERK and Sp1 both suppressed the reduction of TSP50 by bFGF. Deletion and mutation analyses indicated that the Sp1 site, located within the +237/+239 region of the human TSP50 promoter, is the major responsive element for bFGF. Taken together, our results strongly suggest that bFGF mediates TSP50 downregulation by ERK activation, leading to the phosphorylation of Sp1 in this process. J. Cell. Biochem. 111: 75–81, 2010. © 2010 Wiley‐Liss, Inc.
Anti‐atherogenic effect of berberine on LXRα‐ABCA1‐dependent cholesterol efflux in macrophages
Authors: Lee Tzong‐Shyuan , Pan Ching‐Chian , Peng Chien‐Chung , Kou Yu Ru , Chen Chien‐Yu , Ching Li‐Chieh , Tsai Tsung‐Huang , Chen Shu‐Fen , Lyu Ping‐Chiang , Shyue Song‐Kun 
Published: April 2010

AbstractBerberine, a botanical alkaloid purified from Cortidis rhizoma, has effects in cardiovascular diseases, yet the mechanism is not fully understood. Foam cells play a critical role in the progression of atherosclerosis. This study aimed to investigate the effect of berberine on the formation of foam cells by macrophages and the underlying mechanism. Treatment with berberine markedly suppressed oxidized low‐density lipoprotein (oxLDL)‐mediated lipid accumulation, which was due to an increase in cholesterol efflux. Berberine enhanced the mRNA and protein expression of ATP‐binding membrane cassette transport protein A1 (ABCA1) but did not alter the protein level of ABCG1 or other scavenger receptors. Additionally, functional inhibition of ABCA1 with a pharmacological inhibitor or neutralizing antibody abrogated the effects of berberine on cholesterol efflux and lipid accumulation. Moreover, berberine induced the nuclear translocation and activation of liver X receptor α (LXRα) but not its protein expression. Knockdown of LXRα mRNA expression by small interfering RNA abolished the berberine‐mediated protective effects on ABCA1 protein expression and oxLDL‐induced lipid accumulation in macrophages. These data suggest that berberine abrogates the formation of foam cells by macrophages by enhancing LXRα‐ABCA1‐dependent cholesterol efflux. J. Cell. Biochem. 111: 104–110, 2010. © 2010 Wiley‐Liss, Inc.
Immortalized mouse floxed Bmp2 dental papilla mesenchymal cell lines preserve odontoblastic phenotype and respond to BMP2
Authors: Wu Li‐an , Feng Junsheng , Wang Lynn , Mu Yan‐dong , Baker Andrew , Donly Kevin J , Gluhak‐Heinrich Jelica , Harris Stephen E , MacDougall Mary , Chen Shuo 
Published: April 2010

AbstractBone morphogenetic protein 2 (Bmp2) is essential for odontogensis and dentin mineralization. Generation of floxed Bmp2 dental mesenchymal cell lines is a valuable application for studying the effects of Bmp2 on dental mesenchymal cell differentiation and its signaling pathways during dentinogenesis. Limitation of the primary culture of dental mesenchymal cells has led to the development of cell lines that serve as good surrogate models for the study of dental mesenchymal cell differentiation into odontoblasts and mineralization. In this study, we established and characterized immortalized mouse floxed Bmp2 dental papilla mesenchymal cell lines, which were isolated from 1st mouse mandibular molars at postnatal day 1 and immortalized with pSV40 and clonally selected. These transfected cell lines were characterized by RT‐PCR, immunohistochemistry, and analyzed for alkaline phosphatase activity and mineralization nodule formation. One of these immortalized cell lines, iBmp2‐dp, displayed a higher proliferation rate, but retained the genotypic and phenotypic characteristics similar to primary cells as determined by expression of tooth‐specific markers as well as demonstrated the ability to differentiate and form mineralized nodules. In addition, iBmp2‐dp cells were inducible and responded to BMP2 stimulation. Thus, we for the first time described the establishment of an immortalized mouse floxed Bmp2 dental papilla mesenchyma cell line that might be used for studying the mechanisms of dental cell differentiation and dentin mineralization mediated by Bmp2 and other growth factor signaling pathways. J. Cell. Physiol. 225: 132–139, 2010. © 2010 Wiley‐Liss, Inc.
Cancer stem cells: A stride towards cancer cure?
Authors: Sengupta Amitava , Cancelas Jose A. 
Published: April 2010

AbstractDespite major refinements in cancer therapy drugs, our progress at increasing the cure rates of most cancers has been hampered by high relapse rates. A possible biological explanation of the high frequency of relapse and resistance to currently available drugs has been provided by the cancer stem cell (CSC) proposition. Basically, the CSC theory hypothesizes the presence of a hierarchically organized, relatively rare population of cells that is responsible for tumor initiation, self‐renewal and maintenance, mutation accumulation and therapy resistance. Since first postulated by John Dick, multiple reports have provided support for this hypothesis by isolating (more or less) rare cell populations, where the ability to initiate tumors in vivo has been demonstrated. Most progress and stronger data supporting this theory are found predominantly in myelogenous leukemias, whose study has benefited from over half‐a‐century progress in our understanding of the normal hierarchical organization of hematopoiesis. This review, however, also analyzes the advancement in the quantitative and functional analysis of solid tumor stem cells and in the analysis of the tumor microenvironment as specialized, nurturing niches for CSCs. Overall, this review intends to briefly summarize most of the evidences that support the CSC theory and the apparent contradictions, if not skepticism from the scientific community, about its validity for all forms of cancer, or alternatively on just a few cancers initiated by a limited number of somatic or germinal mutations. J. Cell. Physiol. 225: 7–14, 2010. © 2010 Wiley‐Liss, Inc.
Production of polyhydroxyalkanoates: the future green materials of choice
Authors: Akaraonye Everest , Keshavarz Tajalli , Roy Ipsita 
Published: April 2010

AbstractPolyhydroxyalkanoates (PHAs) have recently been the focus of attention as a biodegradable and biocompatible substitute for conventional non degradable plastics. The cost of large‐scale production of these polymers has inhibited its widespread use. Thus, economical, large‐scale production of PHAs is currently being studied intensively. Various bacterial strains, either wild‐type or recombinant have been utilized with a wide spectrum of utilizable carbon sources. New fermentation strategies have been developed for the efficient production of PHAs at high concentration and productivity. With the current advances, PHAs can now be produced to a concentration of 80 g L−1 with productivities greater than 4 g PHA L−1 h−1. These advances will further lower the production cost of PHAs and allow this family of polymers to become a leading biodegradable polymer in the near future. This review describes the properties of PHAs, their uses, the various attempts towards the production of PHAs, focusing on the utilization of cheap substrates and the development of different fermentation strategies for the production of these polymers, an essential step forward towards their widespread use. Copyright © 2010 Society of Chemical Industry
Evaluation of dynamic contrast‐enhanced MRI in detecting renal scarring in a rat injury model
Authors: Wang Bingyin , Sommer Graham , Spielman Daniel , Shortliffe Linda M. Dairiki 
Published: April 2010

AbstractPurpose:To create a reliable rat model with small renal cortical scars and evaluate the accuracy and sensitivity of dynamic contrast‐enhanced MRI in detecting the kinds of lesions that are associated with reflux nephropathy.Materials and Methods:In 16 rats, three unilateral renal cortical lesions were created using either electrocautery or pure alcohol with the contralateral kidney serving as control. MRI on a 1.5 Tesla GE Signa was performed 10–14 days after surgery. After bolus injection of 0.2 mM/Kg Gd‐DTPA, sequential MRI acquisitions were performed using a 4‐inch quadrature birdcage coil. Renal and scar volumes and pathology were compared after scanning and killing.Results:Of the 48 points of injury, 40 (83%) in the 16 rats were detected grossly. Under microscopy, 36 injuries (75%) were detected on mid‐kidney cross‐sections. The average lesion was 4.2 mm3 corresponding to 0.5% of the kidney volume. Using pathological findings as the gold standard, the sensitivity and specificity of scar detection using MRI was 69% and 93%, respectively.Conclusion:A rat model was created to demonstrate the sensitivity of dynamic contrast‐enhanced MRI for detecting renal scars. Alcohol and electrocautery created reliable renal scars that were confirmed pathologically. MRI detected these lesions that averaged 4.2 mm3 (0.5% total renal volume) with sensitivity and specificity of 69% and 93%, respectively. J. Magn. Reson. Imaging 2010;31:1132–1136. © 2010 Wiley‐Liss, Inc.
Exposure to high‐field MRI does not affect cognitive function
Authors: Schlamann Marc , Voigt Melanie A. , Maderwald Stefan , Bitz Andreas K. , Kraff Oliver , Ladd Susanne C. , Ladd Mark E. , Forsting Michael , Wilhelm Hans 
Published: April 2010

AbstractPurposeTo assess potential cognitive deficits under the influence of static magnetic fields at various field strengths some studies already exist. These studies were not focused on attention as the most vulnerable cognitive function. Additionally, mostly no magnetic resonance imaging (MRI) sequences were performed.Materials and MethodsIn all, 25 right‐handed men were enrolled in this study. All subjects underwent one MRI examination of 63 minutes at 1.5 T and one at 7 T within an interval of 10 to 30 days. The order of the examinations was randomized. Subjects were referred to six standardized neuropsychological tests strictly focused on attention immediately before and after each MRI examination. Differences in neuropsychological variables between the timepoints before and after each MRI examination were assessed and P‐values were calculatedResultsOnly six subtests revealed significant differences between pre‐ and post‐MRI. In these tests the subjects achieved better results in post‐MRI testing than in pre‐MRI testing (P = 0.013–0.032). The other tests revealed no significant results.ConclusionThe improvement in post‐MRI testing is only explicable as a result of learning effects. MRI examinations, even in ultrahigh‐field scanners, do not seem to have any persisting influence on the attention networks of human cognition immediately after exposure. J. Magn. Reson. Imaging 2010;31:1061–1066. © 2010 Wiley‐Liss, Inc.
Three‐dimensional balanced steady state free precession imaging of the prostate: Flip angle dependency of the signal based on a two component T2‐decay model
Authors: Storås Tryggve H. , Gjesdal Kjell‐Inge , Gadmar Øystein B. , Geitung Jonn‐Terje , Kløw Nils‐Einar 
Published: April 2010

AbstractPurpose:To investigate the contrast of three‐dimensional balanced steady state free precession (3D bSSFP) in the two component T2 model and to apply the results to optimize 3D bSSFP for prostate imaging at 1.5 Tesla.Materials and Methods:In each of seven healthy volunteers, six 3D bSSFP acquisitions were performed with flip angles (α) equally spaced between 10° and 110°. Predictions of signal and contrast were obtained from synthetic bSSFP images calculated from relaxation parameters obtained from a multi‐spin‐echo acquisition. One biexponential and two monoexponential models were applied. Measured and predicted signals were compared by simple linear regression.Results:The measured contrast to signal ratio increased continuously with α. Mean R2 for the biexponential model was almost constant for α in the range 50–110°. The biexponential model was a better predictor of the measured signal than the monoexponential model. A monoexponential model restricted to the echoes TE = 50–125 ms performed similar to the biexponential model. The predicted contrast peaked at α between 50° and 90°.Conclusion:Prostate imaging with bSSFP benefited from high flip angles. The biexponential model provided good signal prediction while predictions from the monoexponential models are dependent on the range of TE used for T2 determination. J. Magn. Reson. Imaging 2010;31:1124–1131. © 2010 Wiley‐Liss, Inc.
Perforator flap magnetic resonance angiography for reconstructive breast surgery: A review of 25 deep inferior epigastric and gluteal perforator artery flap patients
Authors: Newman Tiffany M. , Vasile Julie , Levine Joshua L. , Greenspun David T. , Allen Robert J. , Chao Minh‐Tam , Winchester Priscilla A. , Prince Martin R. 
Published: April 2010

AbstractPurposeTo evaluate the accuracy of magnetic resonance angiography (MRA) for preoperative mapping of rectus and gluteal muscle perforating arteries prior to autologous flap breast reconstruction.Materials and MethodsPreoperative MRA on 25 consecutive patients undergoing perforator artery‐based autologous breast reconstruction was performed at 1.5 T using 3D liver accelerate volume acquisition (LAVA) of abdominal or gluteal regions acquired during injection of 20 mL of gadobenate dimeglumine with bolus timing optimized using MR fluoroscopy or SmartPrep. Perforator artery size and coordinates relative to umbilicus or top of gluteal crease on 3D MRA were compared to findings at surgery. Reconstructed breast volume estimates from MRA were also compared to weights at harvesting.ResultsIn all, 132 perforator arteries were found at surgery to be located within 1 cm of the coordinates measured on MRA and were surgically verified to be suitable for flap perfusion. Surgery verified the arterial course and caliber through the rectus and gluteal muscles visualized on MRA in 48 of 49 arteries. Volume rendering of 3D MRA predicted a breast reconstruction volume with a mean difference of 47 g compared to measurements at harvesting.ConclusionMRA accurately maps rectus and gluteal muscle perforator arteries for preoperative planning of autologous flaps for breast reconstruction. J. Magn. Reson. Imaging 2010;31:1176–1184. © 2010 Wiley‐Liss, Inc.