bluuebunny/crossref_metadata_2025_split huggingface dataset:
Degradation of PCL‐MPEG diblock copolymer in rat plasma
Authors: Lin Wen‐Jen , Chang Kai‐Ling 
Published: September 2007

AbstractThe poly(ε‐caprolactone)‐co‐poly(ethylene glycol) (PCL‐MPEG) amphiphilic diblock copolymer with molar ratio of ε‐CL to MPEG 81:1 is synthesized via a ring‐opening polymerization without a catalyst. The Mw and Mn molecular weights and the polydispersities are 18,000, 11,000 g/mole and 1.55, respectively. The pegylated amphiphilic copolymer forms micelles with a low critical micelle concentration 6.71 × 10−8 mole/L, and the average particle size of copolymeric micelles is 62.3 ± 12.9 nm. The degradation behavior of diblock copolymer was studied in rat plasma at 37°C for 90 days. The changes of mass, composition, morphology, molecular weight, and thermal property of PCL‐MPEG copolymer were investigated. The decrease of copolymer mass shows two phases with rate constants of 1.91 × 10−1 day−1 in the first‐phase (1–24 h) and 1.77 × 10−3 day−1 in the second‐phase (1–90 days). The degradation of labile ester linkage between PCL block and MPEG block accounts for continuous decrease of copolymer mass in plasma. The decrease of EG molar ratio from 1.30 to 0.67 and prominent reduction of enthalpy of fusion of remained copolymer from 116.5 to 85.2 J/g provide evidences of PCL‐MPEG chain scission. On the other hand, the presence of partially degraded copolymers in the residuals results in its polydispersity increased from 1.55 to 2.24 at the end of 90 days. Nevertheless, the surface erosion of copolymer makes the molecular weight not quite different from its original value. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Copolymerization of D,L‐lactide and glycolide in supercritical carbon dioxide with zinc octoate as catalyst
Authors: Mazarro Rosario , de Lucas Antonio , Gracia Ignacio , Rodríguez Juan F. 
Published: September 2007

AbstractThe objective of the study is the development of a new technique based on supercritical technology for the production of bioabsorbable polymeric microparticles containing pharmaceutical principles, for their use in the controlled release of medicines. For this purpose, the ring‐opening copolymerization of D,L‐lactide and glycolide in supercritical carbon dioxide, using zinc(II) 2‐ethylhexanoate (ZnOct2) as catalyst, was studied. The polymer obtained with ZnOct2 has similar characteristics to that obtained with stannous octoate (SnOct2), the conventional catalyst used up to now for this kind of polymerization process. Experiments were performed at various reaction times, pressures, and stirring rates. The most outstanding result was found by varying the stirring rate, where particles forming agglomerates seem to be obtained at the greater agitation levels. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Transfer of metallic debris from the metal surface of an acetabular cup to artificial femoral heads by scraping: Comparison between alumina and cobalt–chrome heads
Authors: Chang Chong Bum , Yoo Jeong Joon , Song Won Seok , Kim Deug Joong , Koo Kyung‐Hoi , Kim Hee Joong 
Published: September 2007

AbstractWe aimed to investigate the transfer of metal to both ceramic (alumina) and metal (cobalt–chrome) heads that were scraped by a titanium alloy surface under different load conditions. The ceramic and metal heads for total hip arthroplasties were scraped by an acetabular metal shell under various loads using a creep tester. Microstructural changes in the scraped area were visualized with a scanning electron microscope, and chemical element changes were assessed using an energy dispersive X‐ray spectrometry. Changes in the roughness of the scraped surface were evaluated by a three‐dimensional surface profiling system. Metal transfer to the ceramic and metal heads began to be detectable at a 10 kg load, which could be exerted by one‐handed force. The surface roughness values significantly increased with increasing test loads in both heads. When the contact force increased, scratching of the head surface occurred in addition to the transfer of metal. The results documented that metallic debris was transferred from the titanium alloy acetabular shell to both ceramic and metal heads by minor scraping. This study suggests that the greatest possible effort should be made to protect femoral heads, regardless of material, from contact with metallic surfaces during total hip arthroplasty. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Hydrophilic biodegradable microspheres of interferon‐alpha and its pharmacokinetics in mice
Authors: Zheng Cai‐Hong , Yu He‐Yong , Gao Jian‐Qing , Sun Xiao‐Yi , Liang Wen‐Quan 
Published: September 2007

AbstractThe goal of this research was to prepare a kind of hydrophilic sustained release microspheres of interferon‐alpha (IFN‐α), alginate‐chitosan microspheres (ACM) of IFN, and investigate its pharmacokinetics in mice. Alginate microspheres of IFN‐α were first prepared by an emulsion method and further incubated in chitosan to form IFN‐ACM. The influences of isopropanol, bovine serum albumin (BSA), and pH adjustment by isoelectric point of IFN were studied. The optimized IFN‐ACM was obtained with smooth and round morphology, size of 2.18 ± 0.43 μm and entrapment efficiency of 40%. All the concentrations of IFN‐α were determined by IFN assay kits. Finally the pharmacokinetics of IFN‐ACM suspension was studied in ICR mice by intramuscular (I.M.) routes. Compared with IFN solution, Cmax of IFN‐ACM reduced 2.3‐fold, and time to achievement of maximum serum concentrations (Tmax) increased 4‐fold. Meanwhile the area under the concentration‐time curve (AUC) was the same as that of solution. The concentration‐time profiles presented the prolonged serum levels of IFN from IFN‐ACM. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Asynchronous replica exchange for molecular simulations
Authors: Gallicchio Emilio , Levy Ronald M. , Parashar Manish 
Published: September 2007

AbstractAn asynchronous implementation of the replica exchange method that addresses some of the limitations of conventional synchronous replica exchange implementations is presented. In asynchronous replica exchange pairs of processors initiate and perform temperature replica exchanges independently from the other processors, thereby removing the need for processor synchronization found in conventional synchronous implementations. Illustrative calculations on a molecular system are presented that show that asynchronous replica exchange, contrary to the synchronous implementation, is able to utilize at nearly top efficiency loosely coupled pools of processors with heterogeneous speeds, such as those found in computational grids and CPU scavenging environments. It is also shown that employing non‐nearest‐neighbor temperature exchanges, which are straightforward to implement within the asynchronous algorithm, can lead to faster temperature equilibration across processors. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
Encapsulated human primary myoblasts deliver functional hFIX in hemophilic mice
Authors: Wen Jianping , Xu Nong , Li Anna , Bourgeois Jacqueline , Ofosu Frederick A. , Hortelano Gonzalo 
Published: September 2007

AbstractBackgroundHemophilia B is a bleeding disorder caused by defective factor IX (FIX), currently treated by regular infusions of plasma‐derived or recombinant FIX. We propose a gene therapy strategy based on the implantation of cells secreting FIX enclosed in alginate microcapsules as a highly desirable alternative treatment. We have reported sustained delivery of human factor IX (hFIX) in immunocompetent mice implanted with encapsulated primary mouse myoblasts engineered to secrete hFIX. As a step towards the treatment of human patients, in this study we report the implantation of encapsulated human primary myoblasts secreting hFIX in hemophilia B mice.MethodsHuman primary myoblasts were transfected with plasmids pKL4M‐hFIX, pLNM‐βIXL, pMFG‐hFIX, and transduced with retrovirus MFG‐hFIX. Two human primary myoblast clones secreting ∼1 µg hFIX/106 cells/day were enclosed in biocompatible alginate microcapsules and implanted intraperitoneally into SCID and hemophilic mice.ResultsCirculating hFIX (peak of ∼120 ng/ml) was detected in hemophilia B mice on day 1 after implantation. Human FIX delivery was transient, however, becoming undetectable on day 14. Concurrently, anti‐hFIX antibodies were detected. At the same time, activated partial thromboplastin time (APTT) was reduced from 94 s before treatment to 78–80 s. Tail bleeding time decreased from 15 min to 1.5–7 min after treatment, some mice being normalised. These findings indicate that the delivered hFIX is biologically active. Similarly treated NOD/SCID mice had circulating hFIX levels of 170 ng/ml on day 1 that remained detectable for 1 month, albeit at low levels. Cell viability of microcapsules retrieved on day 60 was below 5%.ConclusionsOur findings indicate that encapsulated human primary myoblasts secrete functional hFIX. Furthermore, implantation of encapsulated human primary myoblasts can partially correct the phenotype of hemophilia B mice, supporting the feasibility of this gene therapy approach for hemophilia B. However, the long‐term viability of the encapsulated human myoblasts must first be improved. Copyright © 2007 John Wiley & Sons, Ltd.
Soochong virus and amur virus might be the same entities of hantavirus
Authors: Jiang Jia‐Fu , Zhang Wen‐Yi , Wu Xiao‐Ming , Zhang Pan‐He , Cao Wu‐Chun 
Published: September 2007

AbstractAmur virus (AMRV) and Soochong virus (SOOV) were reported to be carried by Korean field mice (Apodemus peninsulae) in the Far East of Russia, China, and Korea. The distinction and demarcation between these two viruses have been a matter of debate. In order to clarify this issue and to confirm taxonomic position of AMRV and SOOV, the extensive phylogenetic analyses based on entire S segment and entire M segment sequences of AMRV, SOOV and other reference virus strains deposited in GenBank, were carried out using maximum likelihood and distant matrix methods. All inferred phylogenies revealed that all AMRV strains from China and Far East and SOOV (especially SOO‐1/2 strains from Northeastern Korea) shared high identities of nucleotide sequences and were monophyletic distinct from Apodemus agrarius HTNV. Although two genetic sublineages of SOOV exist, these findings revealed that AMRV and SOOV might belong to the same entities of hantavirus. J. Med. Virol. 79:1792–1795, 2007. © 2007 Wiley‐Liss, Inc.
Changing pattern of rotavirus G genotype distribution in Chiang Mai, Thailand from 2002 to 2004: Decline of G9 and reemergence of G1 and G2
Authors: Khamrin Pattara , Peerakome Supatra , Tonusin Supin , Malasao Rungnapa , Okitsu Shoko , Mizuguchi Masashi , Ushijima Hiroshi , Maneekarn Niwat 
Published: September 2007

AbstractGroup A rotaviruses are the most common cause of acute viral diarrhea in humans and animals throughout the world. Previous surveillance studies of group A rotaviruses in Thailand indicated that the dominant types of rotaviruses were changing from time to time. During 2000 and 2001, the G9 rotavirus emerged as the most prevalent genotype, with an exceptionally high frequency (91.6%) in Chiang Mai, Thailand. In the year 2002–2004, group A rotavirus was detected in 98 out of 263 (37.3%) fecal specimens collected from children hospitalized with diarrhea. Of these, 40 (40.8%) were G9P[8], 33 (33.7%) were G1P[8], 23 (23.5%) were G2P[4], and 2 (2.0%) were G3P[9]. The G9P[8] was found to be the most predominant strain in 2002, but the prevalence rate abruptly decreased during the period 2003–2004. In addition, G2P[4] reemerged in the epidemic season of 2003, whereas G1P[8] became the most predominant strain in the following year (2004). Phylogenetic analysis of the VP7 genes revealed that G1, G2, and G9 rotavirus strains clustered together with recently circulating strains, which were isolated from different regional settings in Thailand. In conclusion, the study demonstrated a decrease of incidence of G9P[8] and reemergence of G1P[8] and G2P[4] rotaviruses in Chiang Mai, Thailand during the period 2002–2004. These data imply that the distribution of group A rotavirus genotypes circulating in Chiang Mai, Thailand, changes over time. J. Med. Virol. 79:1775–1782, 2007. © 2007 Wiley‐Liss, Inc.
Mutations associated with lamivudine‐resistance in therapy‐naïve hepatitis B virus (HBV) infected patients with and without HIV co‐infection: Implications for antiretroviral therapy in HBV and HIV co‐infected South African patients
Authors: Selabe S. Gloria , Lukhwareni Azwidowi , Song Ernest , Leeuw Yeegan G.M. , Burnett Rosemary J. , Mphahlele M. Jeffrey 
Published: September 2007

AbstractThis was an exploratory study to investigate lamivudine‐resistant hepatitis B virus (HBV) strains in selected lamivudine‐naïve HBV carriers with and without human immunodeficiency virus (HIV) co‐infection in South African patients. Thirty‐five lamivudine‐naïve HBV infected patients with or without HIV co‐infection were studied: 15 chronic HBV mono‐infected patients and 20 HBV–HIV co‐infected patients. The latter group was further sub‐divided into 13 occult HBV (HBsAg‐negative) and 7 overt HBV (HBsAg‐ positive) patients. HBsAg, anti‐HBs, anti‐HBc, and anti‐HIV 1/2 were determined as part of routine diagnosis using Axsym assays (Abbott Laboratories, North Chicago, IL). Serum samples were PCR amplified with HBV reverse transcriptase (RT) primers, followed by direct sequencing across the tyrosine–methionine–aspartate–aspartate (YMDD) motif of the major catalytic region in the C domain of the HBV RT enzyme. HBV viral load was performed with Amplicor HBV Monitor® test v2.0 (Roche Diagnostics, Penzberg, Germany). HBV lamivudine‐resistant strains were detected in 3 of 15 mono‐infected chronic hepatitis B patients and 10 of 20 HBV–HIV co‐infected patients. To the best of our knowledge, this constitutes the first report of HBV lamivudine‐resistant strains in therapy‐naïve HBV–HIV co‐infected patients. The HBV viral loads for mono‐infected and co‐infected patients ranged from 3.32 × 102 to 3.82 × 107 and <200 to 4.40 × 103 copies/ml, respectively. It remains to be seen whether such pre‐existing antiviral mutations could result in widespread emergence of HBV resistant strains when lamivudine‐containing highly active antiretroviral (ARV) treatment (HAART) regimens become widely applied in South Africa, as this is likely to have potential implications in the management of HBV–HIV co‐infected patients. J. Med. Virol. 79:1750–1754, 2007. © 2007 Wiley‐Liss, Inc.
Fifteen years of Env C2V3C3 evolution in six individuals infected clonally with human immunodeficiency virus type 1
Authors: Kupfer Bernd , Sing Tobias , Schüffler Peter , Hall Rabea , Kurz Ralf , McKeown Astrid , Schneweis Karl‐Eduard , Eberl Wolfgang , Oldenburg Johannes , Brackmann Hans H. , Rockstroh Jürgen K. , Spengler Ulrich , Däumer Martin P. , Kaiser Rolf , Lengauer Thomas , Matz Bertfried 
Published: September 2007

AbstractThe study of the evolution of human immunodeficiency virus type 1 (HIV‐1) requires blood samples collected longitudinally and data on the approximate time point of infection. Although these requirements were fulfilled in several previous studies, the infectious sources were either unknown or heterogeneous genetically. In the present study, HIV‐1 env C2V3C3 (nt 7029‐7315) evolution was examined retrospectively in a cohort of hemophiliacs. Compared to other cohorts, the area of interest here was the infection of six hemophiliacs by the same virus strain, that is, the infecting viruses shared an identical genome. As expected, divergence from the founder sequence as well as interpatient divergence of the predominant virus strains increased significantly over time. Based on the V3 nucleotide sequences, CCR5 usage was predicted exclusively throughout the whole period of infection in all patients. Interestingly, common patterns of viral evolution were detected in the patients of the cohort. Four amino acid substitutions within the V3 loop emerged and persisted subsequently in five (positions 305 and 308 of the HXB2 gp120 reference sequence) and six patients (positions 325 and 328 in HXB2 gp120), respectively. These common changes within the V3 loop are likely to be enforced by HIV‐1 specific immune response. J. Med. Virol. 79:1729–1739, 2007. © 2007 Wiley‐Liss, Inc.
Redetection of HBV lamivudine‐resistant mutations in a patient under entecavir therapy, who had been treated sequentially with nucleos(t)ide analogues
Authors: Rodriguez‐Frias Francisco , Jardi Rosendo , Schaper Melanie , Gimferrer Montserrat , Elefsiniotis Ioannis , Tabernero David , Esteban Rafael , Buti Maria 
Published: September 2007

AbstractDevelopment of hepatitis B virus (HBV)‐resistant strains following nucleos(t)ide analog treatment is a major medical concern. This report describes a case of an adult patient with chronic HBV infection, sequentially treated with the nucleos (t)ide analogues, lamivudine, adefovir, and entecavir. During monotherapy with lamivudine, the patient developed lamivudine‐resistant variants, which were undetectable during adefovir dipivoxil monotherapy. Twenty‐two months after discontinuing lamivudine therapy, the resistant variants were again detected while the patient was receiving entecavir monotherapy. Genotypic analysis by sequencing the HBV polymerase was confirmed with the INNO‐LiPA method. The results of this study suggest that entecavir treatment reselected residual lamivudine‐resistant HBV variants, possibly because lamivudine‐resistant HBV is less susceptible to entecavir than the wild‐type virus. Despite the presence of these variants, the patient has had a complete virological response. J. Med. Virol. 79:1671–1673, 2007. © 2007 Wiley‐Liss, Inc.
Structural variability of the carboxy‐terminus of Epstein–Barr virus encoded latent membrane protein 1 gene in Hodgkin's lymphomas
Authors: Guiretti Deisy M. , Chabay Paola A. , Valva Pamela , Stefanoff Claudio G. , Barros Mário H.M. , De Matteo Elena , Renault Ilana Zalcberg , Preciado Maria Victoria , Hassan Rocio 
Published: September 2007

AbstractEpstein–Barr virus (EBV) is implicated in the pathogenesis of several lymphoid and epithelial neoplasms. Latent membrane protein 1 (LMP1) is the major viral oncogene and it is controversial whether tumor LMP1 variants reflect their geographical predominance or are associated with enhanced oncogenic properties. This study aimed to analyze LMP1 molecular variability of 62 EBV+ Hodgkin's lymphomas and 22 non‐neoplastic controls from Brazil and Argentina. EBV association was characterized by EBER‐ISH, LMP1 immunohistochemistry and PCR assays for EBNA2 and 3C (typing), LMP1 30 bp deletion (del30) and number of 33 bp tandem repeats. LMP1 C‐terminal sequencing was performed in 42 cases. EBV1 was the predominant strain in both geographical Hodgkin's lymphoma groups (average 82%). A higher frequency of del30 variant was observed in lymphomas (41/63) than in non‐neoplastic controls (6/22) (OR 4.97, CI 95% 1.53–16.79; P = 0.005, χ2 test). A large number (5–7) of 33 bp repeat units was characteristic of del30 LMP1 variants (P < 0.0001, Fisher's exact test). Sequence analysis showed a similar mutation spectrum to that described worldwide but none of the current classification schemes could be applied completely. A distinct structural pattern was observed in del30 variants, characterized by a large number of 33 bp repeat units and the presence of a 15 bp insertion encoding the JAK3 Box‐1a motif (3/15 wt vs. 16/20 del30; P = 0.001, χ2 test). The results suggest a pathogenic role for LMP1 del30 variants in Hodgkin's lymphoma from South America and point to particular virus‐host molecular mechanisms, such as genomic instability in LMP1 carboxy‐terminus, leading to enhanced production and selection of these deletion variants. J. Med. Virol. 79:1722–1730, 2007. © 2007 Wiley‐Liss, Inc.
A new method for simultaneous estimation of unsaponifiable constituents of rice bran oil using HPTLC
Authors: Afinisha Deepam Lawrence S. , Soban Kumar Dasiah R. , Sundaresan Andikkannu , Arumughan Chami 
Published: September 2007

AbstractRice bran oil (RBO) is rich in a variety of bioactive phytochemicals otherwise known as unsaponifiable constituents (USC). Oryzanols, phytosterols, tocols, etc. are the major USC in RBO; the methods presently used for their estimation involve different techniques and require pretreatment of the sample. In this paper standardization of a simple method for simultaneous estimation of USC directly from RBO using HPTLC is presented. The method involves a two‐stage separation of USC on a precoated silica gel 60 F254 TLC plate viz.: TLC‐1 to separate sterols, oryzanols and tocols; TLC‐2 to separate steryl esters, wax, and squalene. Calibration plots using the respective standards were made to determine LOD, LOQ, and linear regression equations. Recovery studies were also conducted and the values ranged from 93.45 to 101.97%. The LOD and LOQ values showed the sensitivity of the method. The instrumental precision was found to be in the range of 0.30 to 1.18 CV%. Quantitative estimation of USC in crude RBO and refined RBO using this method gave a concentration of 52.80 mg/g of USC in the crude and 33.48 mg/g in the refined oil. The present method for estimation of USC using HPTLC is fast, simple, accurate, precise, and sensitive, as demonstrated here.
‘We're not the Barmy Army!’: reflections on the sports tourist experience
Authors: Morgan Michael 
Published: September 2007

AbstractThis paper explores the dynamics of the interaction between the sports tourist and the destination through the insights of experience management literature applied to the 2005 British and Irish Lions rugby tour of New Zealand. It contrasts the managerial view that sports tourism is something to be controlled and stage‐managed, with the consumer behaviour view of the experience as a subjective emotional journey full of personal, social and cultural meanings. A holistic model of the interactions between visitors and destinations is proposed. From this, it is suggested that rather than trying to channel sports tourists into special areas, planners should give them space to create their own experiences by encouraging them to explore for themselves. As a result, the positive impact of sports tourism will be spread wider in the economy of the region. Copyright © 2007 John Wiley & Sons, Ltd.
Running away from home: understanding visitor experiences and behaviour at sport tourism events
Authors: Shipway Richard , Jones Ian 
Published: September 2007

AbstractExisting sport tourism research has been subject to claims of lacking coherence, theoretical underpinning and empirical support. This paper addresses these issues through an examination of a group of distance runners participating in theCyprus International Four‐day Challenge. Using the concepts of ‘serious leisure’ and social identification, the behaviours of this group of sport tourists are described and explained. The key finding was the strength of identification that participants had with the activity, and the nature of the event itself, which made this identity much more salient than other identities during the course of the event. This sense of identification was used to explain the unique ethos of the group, the use of significant personal effort, the perseverance of participants, the durable benefits obtained by the runners and the career structure associated with this social world. Copyright © 2007 John Wiley & Sons, Ltd.