bluuebunny/crossref_metadata_2025_split huggingface dataset:
UV‐embossed microchannel in biocompatible polymeric film: Application to control of cell shape and orientation of muscle cells
Authors: Shen Jin‐Ye , Chan‐Park Mary Bee‐Eng , Feng Zhi‐Qin , Chan Vincent , Feng Zhi‐Wei 
Published: November 2005

AbstractThis article shows that ultra violet (UV) micro‐embossing can be successfully used for fabricating biocompatible micropatterned films with microchannels separated by high aspect ratio microwalls. Eight series of micropatterns were investigated; the width of the microwall was either 10 or 25 μm and that of the microchannel either 40, 80, 120, or 160 μm. The material investigated was principally polyurethane diacrylate. The UV‐embossed micropattern was extracted with methanol, converting the micropatterns from cytotoxic to biocompatible. The typical UV embossing method was modified by using a marginally adhesive polyester substrate, which facilitates demolding but is removable before methanol extraction to avoid fragmentation of the embossed micropatterns. The effect of the micropatterns on A7r5 smooth muscle cells and C2C12 skeletal muscle cells was investigated. The dimensions of both channel and wall have significant effects on the elongation of both muscle cells. In the narrower 40‐μm channel, the C2C12 cells merged together to form myofibers. These results indicate that UV‐embossed micropatterns may present a useful scaffold for in vitro cell shape and orientation control needed in vascular and muscle tissue engineering. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Stair ascent kinematics affect UHMWPE wear and damage in total knee replacements
Authors: Cottrell Jocelyn M. , Babalola Omotunde , Furman Bridgette S. , Wright Timothy M. 
Published: November 2005

AbstractInvestigations were performed to characterize the wear patterns of tibial inserts in a load‐controlled knee simulator by incorporating both normal gait and clinically acquired stair climbing kinematics and load conditions. Two different tibial insert designs were evaluated: the NexGen Cruciate Retaining Augmentable and NexGen Legacy Posterior Stabilized inserts. Two test conditions were run: standard gait only, and gait with bouts of stair climbing at a ratio of 70:1. Gravimetric wear measurements, damage and contact area assessments, and kinematic evaluations were performed. The addition of stair climbing kinematics significantly affected the wear behavior. Regardless of design, wear rates for standard gait tests were significantly higher than those that included bouts of stair climbing. The damage modes seen in both test conditions were primarily burnishing with secondary scratching and pitting. At 2 Mc, the damage areas were not significantly different between the two designs, but the damage area with stair climbing was significantly larger than that with gait alone. The fact that even small bouts of an additional activity of daily living could markedly impact wear simulator results calls into question the usefulness of studies that rely solely on kinematics and load inputs assumed from level gait. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
In vitro wear of resin‐based materials—Simultaneous corrosive and abrasive wear
Authors: Correr Gisele Maria , Alonso Roberta Caroline Bruschi , Sobrinho Lourenço Correr , Puppin‐Rontani Regina Maria , Ferracane Jack Liborio 
Published: November 2005

AbstractThe aim of this study was to evaluate the wear of resin‐based materials caused by the association of abrasive and corrosive processes. Twenty specimens were prepared for each material, cast in epoxy in acrylic rings, polished, and profiled with an MTS 3D Profiler. Antagonists were made from deciduous molars. Specimens were distributed into eight groups (n = 10), according to the material (Filtek Supreme, Point 4, Dyract AP, and Fuji II LC) and the type of slurry (neutral and acidic), and then cycled 100,000 times in the OHSU oral wear simulator. The specimens were cleaned and reprofiled. Volume loss and maximum depth were determined. ANOVA and Tukey's test were used for data analysis (p < 0.05). The area of the wear facet on the antagonist was also measured. Composites displayed less wear than the compomer and the resin‐modified glass ionomer. Significant differences also were found for cusp wear, with a significant positive correlation shown between cusp and material wear. The acidic slurry significantly increased the wear of the materials compared to the neutral slurry. Exposure to acidic slurry accelerated the wear of resin‐based materials. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Advanced nanocomposite materials for orthopaedic applications. I. A long‐term in vitro wear study of zirconia‐toughened alumina
Authors: Affatato S. , Torrecillas R. , Taddei P. , Rocchi M. , Fagnano C. , Ciapetti G. , Toni A. 
Published: November 2005

AbstractThe use of ceramic‐on‐ceramic (alumina‐ and zirconia‐based) couplings in hip joint prostheses has been reported to produce lower wear rates than other combinations (i.e., metal‐on‐polyethylene and ceramic‐on‐polyethylene). The addition of zirconia into an alumina matrix (zirconia‐toughened alumina, ZTA) has been reported to result in an enhancement of flexural strength, fracture toughness, and fatigue resistance. The development of new processing routes in nonaqueous media has allowed to obtain high‐density ZTA nanocomposites with a very homogeneous microstructure and a significantly smaller and narrower particle‐size distribution of zirconia than conventional powder mixing methods. The aim of the present study was to set up and validate a new ZTA nanocomposite by testing its biocompatibility and wear behavior in a hip‐joint simulator in comparison with commercial alumina and experimental alumina specimens. The primary osteoblast proliferation onto ZTA nanocomposite samples was found to be not significantly different from that onto commercial alumina samples. After 7 million cycles, no significant differences were observed between the wear behaviors of the three sets of cups. In this light, it can be affirmed that ZTA nanocomposite materials can offer the option of improving the lifetime and reliability of ceramic joint prostheses. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Characterization of functionally graded hydroxyapatite/titanium composite coatings plasma‐sprayed on Ti alloys
Authors: Chen Chun‐Cheng , Huang Tsui‐Hsien , Kao Chia‐Tze , Ding Shinn‐Jyh 
Published: November 2005

AbstractBioceramic coatings like hydroxyapatite (HA) have shown promising bioactive properties in load‐bearing implant applications. The aim of this work is to deposit functionally graded HA/Ti layers consisting of an underlying Ti bond coat, the alternating layer, and an HA top‐layer on Ti6Al4V substrates using plasma spray to improve the coating–substrate interface properties. The alternating layers were created by means of changing the feeding rate and input power of Ti and HA powders, which gradually decrease Ti content with increasing depth from the Ti bond‐coat. The major consideration is to examine the stability of the graded coatings. Experimental results indicated that surface chemistry and morphology of the graded coatings were similar to those of monolithic HA coatings. The bond strength values of the as‐sprayed graded coatings were much superior to those of monolithic HA coatings. The cyclic fatigue did have a statistically significant effect on bond strength of monolithic HA coatings, with a decrease of 23%. However, the graded coatings were able to survive 1 million cycles of loading in air without significantly reduced bond strength. The in vitro electrochemical measurement results also indicated that the graded coatings had a more beneficial and desired behavior than monolithic HA coatings after fatigue. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
A charge‐scaling implementation of the variational electrostatic projection method
Authors: Gregersen Brent A. , York Darrin M. 
Published: November 2005

AbstractTwo new charge‐scaling methods for efficient modeling of the solvated macromolecular environment in hybrid QM/MM calculations of biological reactions are presented. The methods are extensions of the variational electrostatic projection (VEP) method, and allows a subset of atomic charges in the external environment to be adjusted to mimic, in the active dynamical region, the electrostatic potential and field due to the large surrounding macromolecule and solvent. The method has the advantages that it offers improved accuracy, does not require the use of a three‐dimensional grid or auxiliary set of fitting points, and requires only minor molecular simulation code modifications. The VEP−cs and VEP‐RVM+cs methods are able to attain very high accuracy (relative force errors of 10−7 or better with appropriate choice of control parameters), and take advantage of a recently introduced set of high‐order discretization schemes and Gaussian exponents for boundary element solvation and VEP methods. The methods developed here serve as potentially powerful tools in the arsenal of computational techniques used in multiscale computational modeling problems. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 103–115, 2006
Cyclic m‐cycle systems with m ≤ 32 or m = 2q with q a prime power
Authors: Wu Shung‐Liang , Fu Hung‐Lin 
Published: November 2005

AbstractIn this paper, the necessary and sufficient conditions for the existence of cyclic 2q‐cycle and m‐cycle systems of the complete graph with q a prime power and 3 ≤ m ≤ 32 are given. © 2005 Wiley Periodicals, Inc. J Combin Designs
The number of triangles in 2‐factorizations
Authors: Sui Qidi , Du Beiliang 
Published: November 2005

AbstractGiven an arbitrary 2‐factorization ${\cal F} = {F_{1},F_{2}, \cdots , F_{v - 1/2}}$ of $K_{v}$, let δi be the number of triangles contained in Fi, and let δ = Σδi. Then $\cal F$ is said to be a 2‐factorization with δ triangles. Denote by Δ(v), the set of all δ such that there exists a 2‐factorization with δ triangles. Let

where

Dejter et al. 1 proved that when v ≡ 1 or 3 (mod 6), apart from some small exceptions, and some additional 11 possible exceptions, Δ(v) = PΔ (v). In this paper, we consider the remaining case v ≡ 5 (mod 6). We will prove that when v ≡ 5 (mod 6), apart from some small exceptions, and some additional 9 possible exceptions, Δ (v) = PΔ (v). © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 277–289, 2006
Physiology and pathology of notch signalling system
Authors: Bianchi Silvia , Dotti Maria Teresa , Federico Antonio 
Published: November 2005

AbstractNotch proteins encode a family of transmembrane receptors that are part of a signalling transduction system known as Notch signalling, an extremely conserved and widely used mechanism regulating programs governing growth, apoptosis and differentiation in metazoans. Notch signalling begins when the Notch receptor binds ligands and ends when the Notch intracellular domain enters the nucleus and activates transcription of target genes. This core pathway is subjected to a wide array of regulatory influences and protein‐protein interactions and is correlated with other signalling pathway. This review will sumarize recent findings concerning the physiology and pathology of Notch signalling in vascular development and homeostasis. Moreover, the clinical phenotypes of Notch3 signalling system pathology will be described, with particular regard to CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy) for which the most recent pathogenetic hypotheses are reported. J. Cell. Physiol. 207: 300–308, 2006. © 2005 Wiley‐Liss, Inc.
Four novel RUNX2 mutations including a splice donor site result in the cleidocranial dysplasia phenotype
Authors: Kim Hyo‐Jin , Nam Soon‐Hyeun , Kim Hyun‐Jung , Park Hyo‐Sang , Ryoo Hyun‐Mo , Kim Shin‐Yoon , Cho Tae‐Joon , Kim Seung‐Gon , Bae Suk‐Chul , Kim In‐San , Stein Janet L. , van Wijnen Andre J. , Stein Gary S. , Lian Jane B. , Choi Je‐Yong 
Published: November 2005

AbstractCleidocranial dysplasia (CCD) is an autosomal dominant disorder caused by haploinsufficiency of the RUNX2 gene. In this study, we analyzed by direct sequencing RUNX2 mutations from eleven CCD patients. Four of seven mutations were novel: two nonsense mutations resulted in a translational stop at codon 50 (Q50X) and 112 (E112X); a missense mutation converted arginine to glycine at codon 131 (R131G); and an exon 1 splice donor site mutation (donor splice site GT/AT, IVS1 + 1G > A) at exon 1–intron junction resulted in the deletion of QA stretch contained in exon 1 of RUNX2. We focused on the functional analysis of the IVS1 + 1G > A mutation. A full‐length cDNA of this mutation was cloned (RUNX2Δe1) and expressed in Chinese hamster ovary (CHO) and HeLa cells. Functional analysis of RUNX2Δe1 was performed with respect to protein stability, nuclear localization, DNA binding, and transactivation activity of a downstream RUNX2 target gene. Protein stability of RUNX2Δe1 is similar to wild‐type RUNX2 as determined by Western blot analysis. Subcellular localization of RUNX2Δe1, assessed by in situ immunofluorescent staining, was observed with partial retention in both the nucleus and cytoplasm. This finding is in contrast to RUNX2 wild‐type, which is detected exclusively in the nucleus. DNA binding activity was also compromised by the RUNX2Δe1 in gel shift assay. Finally, RUNX2Δe1 blocked transactivation of the osteocalcin gene determined by transient transfection assay. Our findings demonstrate for the first time that the CCD phenotype can be caused by a splice site mutation, which results in the deletion of N‐terminus amino acids containing the QA stretch in RUNX2 that contains a previously unidentified second nuclear localization signal (NLS). We postulate that the QA sequence unique to RUNX2 contributes to a competent structure of RUNX2 that is required for nuclear localization, DNA binding, and transactivation function. J. Cell. Physiol. 207: 114–122, 2006. © 2005 Wiley‐Liss, Inc.
Dengue in the Dominican Republic: Epidemiology for 2004
Authors: Cabrera‐Batista Brinia , Skewes‐Ramm Ronald , Fermin Cesar D. , Garry Robert F. 
Published: November 2005

AbstractThe Dominican Republic (DR) has experienced tremendous increase in the number of cases of dengue virus (DENV) reported in the past few years. There are four serotypes of DENV (1–4), and each can cause classic dengue fever (DF), dengue hemorrhagic fever (DHF), or dengue shock syndrome (DSS). DENV‐1–4 are currently circulating in the DR; however, the Department of Epidemiology of the Dominican Republic (DIEGPI) has been able to isolate only DENV‐2 and DENV‐4. In the DR, the development of DENV infection occurred primarily in the second semester of the year. Since the DR instituted a vigilant approach to dengue infections, there have been three major outbreaks detected: one in 1998, one in 2000, and one in 2002. DF is the clinical presentation most currently seen at clinics, accounting for about 75% of cases, while patients with DHF account for about 19% of cases seen. Currently, there are seven provinces in which the total number of dengue cases per 100,000 inhabitants is higher than 32. With a vigilant approach, the DR should continue to see success in controlling the DENV outbreak. Microsc. Res. Tech. 68:250–254, 2005. © 2005 Wiley‐Liss, Inc.
HCV‐hepatocellular carcinoma: New findings and hope for effective treatment
Authors: Dash Srikanta , Haque Salima , Joshi Virendra , Prabhu Ramesh , Hazari Sidhartha , Fermin Cesar , Garry Robert 
Published: November 2005

AbstractWe present here a comprehensive review of the current literature plus our own findings about in vivo and in vitro analysis of hepatitis C virus (HCV) infection, viral pathogenesis, mechanisms of interferon action, interferon resistance, and development of new therapeutics. Chronic HCV infection is a major risk factor for the development of human hepatocellular carcinoma. Standard therapy for chronic HCV infection is the combination of interferon alpha and ribavirin. A significant number of chronic HCV patients who cannot get rid of the virus infection by interferon therapy experience long‐term inflammation of the liver and scarring of liver tissue. Patients who develop cirrhosis usually have increased risk of developing liver cancer. The molecular details of why some patients do not respond to standard interferon therapy are not known. Availability of HCV cell culture model has increased our understanding on the antiviral action of interferon alpha and mechanisms of interferon resistance. Interferons alpha, beta, and gamma each inhibit replication of HCV, and the antiviral action of interferon is targeted to the highly conserved 5′UTR used by the virus to translate protein by internal ribosome entry site mechanism. Studies from different laboratories including ours suggest that HCV replication in selected clones of cells can escape interferon action. Both viral and host factors appear to be involved in the mechanisms of interferon resistance against HCV. Since interferon therapy is not effective in all chronic hepatitis C patients, alternative therapeutic strategies are needed to treat chronic hepatitis C patients not responding to interferon therapy. We also reviewed the recent development of new alternative therapeutic strategies for chronic hepatitis C, which may be available in clinical use within the next decade. There is hope that these new agents along with interferon will prevent the occurrence of hepatocellular carcinoma due to chronic persistent hepatitis C virus infection. This review is not inclusive of all important scientific publications due to space limitation. Microsc. Res. Tech. 68:130–148, 2005. © 2005 Wiley‐Liss, Inc.
Alterations of lymphocyte membranes during HIV‐1 infection via multiple and simultaneous entry strategies
Authors: Fermin Cesar , Garry Robert 
Published: November 2005

AbstractHuman immunodeficiency virus type 1 (HIV‐1) must bind to and enter lymphocytes to replicate and cause the acquired immunodeficiency syndrome. The association of viral particles with the lymphocyte plasma membrane may vary according to a multitude of unknown variables, including lymphocyte membrane receptor mobilization, lipid raft aggregation, clathrin, caveolin, endosomes, microendosome‐mediated penetration or penetration through a hole in the membrane. The time course of this delivery appears to be short. Fusion of the virion membrane and lymphocyte plasma membrane leads to destabilization of the lymphocyte membrane. Five morphological stages of membrane alteration were observed in the infected lymphocytes: (1) swelling, (2) splitting, (3) fusion, (4) breaking, and (5) thinning of the lipid bilayer. These plasma membrane alterations were not contributed by fixation artifacts, because the dimensions and distance between the subunits of the surface glycoprotein (SU, gp120) and the transmembrane glycoprotein (gp41) of the viral particles adjacent to the infected cells and processed at the same time remained unchanged. Destabilization of lipid raft patches in the lymphocyte plasma membrane by unknown variables may facilitate HIV‐1 penetration of lymphocyte, and other cell types. This a combined review of the pertinent literature with our data showing that HIV‐1 may take advantage of multiple penetration approaches simultaneously in the same cell type (H9) to overwhelm the infected cells. The ultrastructural details of H9 cultured cells infected in vitro with HIV‐1 contribute to our understanding of viral particle association with the plasma membrane of infected cells. Microsc. Res. Tech. 68: 149–167, 2005. © 2005 Wiley‐Liss, Inc.
Dystrophin expression in the mdx mouse after localised and systemic administration of a morpholino antisense oligonucleotide
Authors: Fletcher Susan , Honeyman Kaite , Fall Abbie M. , Harding Penny L. , Johnsen Russell D. , Wilton Steve D. 
Published: November 2005

AbstractBackgroundDuchenne and Becker muscular dystrophies are allelic disorders arising from mutations in the dystrophin gene. Duchenne muscular dystrophy is characterised by an absence of functional protein, while Becker muscular dystrophy is usually caused by in‐frame deletions allowing synthesis of some functional protein. Treatment options are limited, and we are investigating the potential of transcript manipulation to overcome disease‐causing mutations. Antisense oligonucleotides have been used to induce specific exon removal during processing of the dystrophin primary transcript and thereby by‐pass protein‐truncating mutations. The antisense oligonucleotide chemistry most widely used to alter pre‐mRNA processing is 2′‐O‐methyl‐modified bases on a phosphorothioate backbone.MethodsThe present studies evaluate 2′‐O‐methylphosphorothioate, peptide nucleic acid and morpholino antisense oligonucleotides in the mdx mouse model of muscular dystrophy, which has a nonsense mutation in exon 23 of the dystrophin gene.ResultsWe demonstrate dystrophin expression in mdx mouse tissues after localised and systemic delivery of a morpholino antisense oligonucleotide designed to target the dystrophin exon 23 donor splice site.ConclusionsThe stability of the morpholino structural type, and the fact that it can be delivered to muscle in the absence of a delivery reagent, render this compound eminently suitable for consideration for therapeutic exon skipping to address dystrophin mutations. Copyright © 2005 John Wiley & Sons, Ltd.
Combinatorial engineering of a gene therapy vector: directed evolution of adeno‐associated virus
Authors: Perabo Luca , Endell Jan , King Susan , Lux Kerstin , Goldnau Daniela , Hallek Michael , Büning Hildegard 
Published: November 2005

AbstractBackgroundViruses are being exploited as vectors to deliver therapeutic genetic information into target cells. The success of this approach will depend on the ability to overcome current limitations, especially in terms of safety and efficiency, through molecular engineering of the viral particles.MethodsHere we show that in vitro directed evolution can be successfully performed to randomize the viral capsid by error prone PCR and to obtain mutants with improved phenotype.ResultsTo demonstrate the potential of this technology we selected several adeno‐associated virus (AAV) capsid variants that are less efficiently neutralized by human antibodies. These mutations can be used to generate novel vectors for the treatment of patients with pre‐existing immunity to AAV.ConclusionsOur results demonstrate that combinatorial engineering overcomes the limitations of rational design approaches posed by incomplete understanding of the infectious process and at the same time offers a powerful tool to dissect basic viral biology by reverse genetics. Copyright © 2005 John Wiley & Sons, Ltd.
A note on the cover degeneracy of graphs
Authors: Zhang Li , Wu Baoyindureng 
Published: November 2005

AbstractWe give a 4‐chromatic planar graph, which admits a vertex partition into three parts such that the union of every two of them induces a forest. This solves a problem posed by Böhme. Also, by constructing an infinite sequence of graphs, we show that the cover degeneracy can be arbitrarily less than the chromatic number. © 2005 Wiley Periodicals, Inc. J Graph Theory