bluuebunny/crossref_metadata_2025_split huggingface dataset:
hTERT inhibits the Epstein‐Barr virus lytic cycle and promotes the proliferation of primary B lymphocytes: Implications for EBV‐driven lymphomagenesis
Authors: Terrin Liliana , Dolcetti Riccardo , Corradini Irene , Indraccolo Stefano , Col Jessica Dal , Bertorelle Roberta , Bonaldi Laura , Esposito Giovanni , De Rossi Anita 
Published: April 2007

AbstractTransformation of primary B lymphocytes by Epstein‐Barr Virus (EBV) requires the establishment of a latent infection, the expression of several latent viral proteins and a sustained telomerase activity. We investigated the interplay between the activation of human telomerase reverse transcriptase (hTERT), the catalytic rate‐limiting component of the telomerase complex, and the expression of latent/lytic EBV genes during the establishment of a stably latent EBV infection of normal B lymphocytes. Cell cultures at early passages after EBV infection greatly differed in their timing of hTERT expression and telomerase activation. Induction of hTERT was dependent on the balance between latent and lytic EBV gene expression, being positively associated with a high ratio of latent/lytic isoforms of latent membrane protein 1, and negatively associated with the expression of BZLF1 gene, the main activator of the viral lytic cycle. In turn, hTERT expression was followed by a decrease in EBV lytic gene expression and virus production. Ectopic expression of hTERT in BZLF1‐positive B cell cultures resulted in BZLF1 down‐regulation, increased resistance to lytic cycle induction, and enhanced in vitro growth properties, whereas hTERT inhibition by siRNA triggered the activation of the EBV lytic cycle. These findings indicate that hTERT contributes by multiple mechanisms to the EBV‐driven transformation of B lymphocytes and suggest that hTERT may constitute a therapeutic target for EBV‐associated B cell lymphomas. © 2007 Wiley‐Liss, Inc.
The screening of the second‐site suppressor mutations of the common p53 mutants
Authors: Otsuka Kazunori , Kato Shunsuke , Kakudo Yuichi , Mashiko Satsuki , Shibata Hiroyuki , Ishioka Chikashi 
Published: April 2007

AbstractSecond‐site suppressor (SSS) mutations in p53 found by random mutagenesis have shown to restore the inactivated function of some tumor‐derived p53. To screen novel SSS mutations against common mutant p53s, intragenic second‐site (SS) mutations were introduced into mutant p53 cDNA in a comprehensive manner by using a p53 missense mutation library. The resulting mutant p53s with background and SS mutations were assayed for their ability to restore the p53 transactivation function in both yeast and human cell systems. We identified 12 novel SSS mutations including H178Y against a common mutation G245S. Surprisingly, the G245S phenotype is rescued when coexpressed with p53 bearing the H178Y mutation. This result indicated that there is a possibility that intragenic suppressor mutations might restore the protein function in an intermolecular manner. The intermolecular mechanism may lead to novel strategies for restoring inactivated p53 function and tumor suppression in cancer treatment. © 2007 Wiley‐Liss, Inc.
Human papillomavirus infection in women in Shenzhen City, People's Republic of China, a population typical of recent Chinese urbanisation
Authors: Wu Rui‐fang , Dai Min , Qiao You‐lin , Clifford Gary M. , Liu Zhi‐hua , Arslan Annie , Li Ni , Shi Ju‐fang , Snijders Peter J.F. , Meijer Chris J.L.M. , Franceschi Silvia 
Published: April 2007

AbstractSelect cancer registries report that cervical cancer is relatively rare in the People's Republic of China, but may not be representative of the entire country. We carried out a survey of human papillomavirus (HPV) prevalence in 3 samples of women, i.e., general population, factory workers, and tertiary sector workers, in Shenzhen City in 2004. All participants were interviewed and offered gynaecological examination. HPV detection in exfoliated cervical cells was performed using a GP5+/6+ PCR‐based assay. Overall HPV prevalence was 18.4% among the general population (n = 534), 11.2% among factory workers (n = 269) and 18.8% among tertiary sector workers (n = 224). Corresponding prevalence for high‐risk HPV types was 13.5%, 8.2% and 13.8%, respectively. The most commonly found HPV types were HPV16, 52, 58, 31 and 39. HPV prevalence significantly increased with age in the general population, whereas it was highest below age 25 years in tertiary sector workers. Associations of HPV prevalence with indicators of sexual behaviour were stronger among tertiary sector workers than in the other samples of women. High HPV prevalence in all age groups and the appearance of a ‘western‐type’ peak in HPV prevalence among young women employed in the tertiary sector raise important questions concerning the real cervical cancer burden, and its control, in urban China. © 2007 Wiley‐Liss, Inc.
Genetic investigation of DNA‐repair pathway genes PMS2, MLH1, MSH2, MSH6, MUTYH, OGG1 and MTH1 in sporadic colon cancer
Authors: Schafmayer Clemens , Buch Stephan , Egberts Jan Hendrik , Franke Andre , Brosch Mario , El Sharawy Abdou , Conring Mareike , Koschnick Maralde , Schwiedernoch Sven , Katalinic Alexander , Kremer Bernd , Fölsch Ulrich R. , Krawczak Michael , Fändrich Fred , Schreiber Stefan , Tepel Jürgen , Hampe Jochen 
Published: April 2007

AbstractMutations in DNA repair genes have previously been identified as causative factors for hereditary nonpolyposis colon cancer (HNPCC). Recent evidence also supports an association between DNA sequence variation in these genes and sporadic colorectal carcinoma (CRC). Genetic investigation of DNA repair genes PMS2, MLH1, MSH2, MSH6, MUTYH, OGG1 and MTH1, as possible susceptibility factors for sporadic CRC, was done using both a haplotype tagging and a candidate (i.e. coding) single nucleotide polymorphism (SNP) approach. Some 1,068 patients with operated CRC (median age at diagnosis: 59 years) were compared to 738 sex‐matched control individuals (median age: 67 years). Haplotype tagging SNPs, previously reported risk variants and all known coding SNPs with a minor allele frequency >0.005 were genotyped in PMS2 (N = 10), MLH1 (N = 11), MSH2 (N = 18), MSH6 (N = 15), MUTYH (N = 7), OGG1 (N = 11) and MTH1 (N = 3). No evidence for an association between CRC and any of the 7 genes was detected, neither with the tagging or coding SNPs nor in a sliding window haplotype analysis (all nominal p‐values >0.05). The previously reported risk variants D132H in MLH1 and R154H in OGG1 were not even observed in the German population. Genetic CRC risk factors so far identified in DNA repair genes seem to be rare and population‐specific. Their association with the disease could not be replicated in German CRC samples. It remains to be elucidated by more systematic, large‐scale experiments whether common variants in the same genes, but present across populations, represent risk factors for sporadic CRC. © 2007 Wiley‐Liss, Inc.
Yao C, Stern P, Zhang L. Elevated expression of CaMKIIγ during osteoclastogenesis and its functional implications. J Cell Biochem 2006; DOI 10.1002/jcb.21155
Authors: Zhang Liang 
Published: April 2007

AbstractThe original article to which this Retraction refers was published in J Cell Biochem 2006; DOI 10.1002/jcb.21155. © 2006 Wiley‐Liss, Inc..
Tandem high‐dose chemotherapy with autologous peripheral hematopoietic progenitor cell rescue as consolidation therapy for patients with high‐risk Ewing family tumors
Authors: Burke Michael J. , Walterhouse David O. , Jacobsohn David A. , Duerst Reggie E. , Kletzel Morris 
Published: April 2007

AbstractThe role of tandem high‐dose chemotherapy (HDC) with autologous peripheral hematopoietic progenitor cell rescue (APHPCR) in patients with Ewing Family Tumors (EFT) is controversial. We initiated treatment for eight consecutive patients with high‐risk EFT with HDC and APHPCR from 1992 to 2003. There were no treatment related deaths. Four patients remain in complete remission, including three who did not undergo local therapy to bone at either the primary or metastatic sites. Our experience has shown that treatment of EFT patients with tandem HDC with APHPCR may benefit a subgroup of high‐risk patients in whom optimal local therapy is not possible. Pediatr Blood Cancer 2007;49:196–198. © 2007 Wiley‐Liss, Inc.
Proliferative index and CD15 expression in pediatric classical Hodgkin lymphoma
Authors: Dinand Veronique , Malik Ajay , Unni Rajani , Arya Laxman S. , Pandey R.M. , Dawar Ramesh 
Published: April 2007

AbstractBackgroundThis study was conducted to assess the clinical and prognostic significance of lack of CD15 expression, proliferative index (PI), and expression of tumor suppressor protein p53 in pediatric classical Hodgkin lymphoma (CHL).ProcedurePre‐treatment lymph node (LN) biopsies were studied by immunohistochemistry for immunophenotyping of the lymphoma and with Ki‐67 (PI) and p53 antibodies. Expression of CD15 antigen on the Hodgkin and Reed‐Sternberg (H‐RS) cells, proliferation, and apoptosis parameters were correlated with clinical stage, response to chemotherapy alone, overall (OS) and failure‐free survival (FFS).ResultsOne hundred and twenty‐one children with CHL were studied. Expression of Ki‐67 and p53 in H‐RS cells was seen in 100% and 89.9% of the cases, respectively. Loss of CD15 expression, seen in 12 (9.9%) cases, was significantly associated with p53 negativity and was an independent prognostic factor for poor OS and poor FFS. PI ≤ 74% was an independent prognostic factor for poor FFS.ConclusionsLoss of CD15 expression in CHL might be related to p53 dysregulation. High PI in HL might reflect a high level of endomitosis within tumor cells, and could lead to higher sensitivity to chemotherapy. Low pre‐treatment PI and lack of CD15 expression were found to be predictive factors for poor FFS in pediatric CHL. Pediatr Blood Cancer 2008;50:280–283. © 2007 Wiley‐Liss, Inc.
Biological functions of low‐frequency vibrations (phonons). 7. The impetus for DNA to accommodate intercalators
Authors: Chou K. C. , Maggiora G. M. 
Published: April 2007

AbstractEach intact segment within a DNA molecule (i.e. a stretch of double helix without disrupted hydrogen bonds) can generate a low‐frequency standing wave [Chou, K. C. (1984), Biochemical Journal, 221,27‐31] of nearly identical frequency to that of other intact segments. Therefore, coupling among this kind of segment can lead to a spontaneous low‐frequency resonance. Such resonance can also cause a local ‘DNA‐quake’ to occur spontaneously, and this kind of quake‐like motion can produce a sufficiently large ‘hole’ for larger intercalators to gain entrance into (and exit from) the DNA.
Upper critical solution temperature behaviour in poly(ether ether sulphone)/poly(ether ether ketone‐co‐ ether ether sulphone) blends
Authors: Sham C. K. , Lau C. H. , Williams D. J. , Karasz F. E. , Macknight W. J. 
Published: April 2007

AbstractUpper critical solution temperature (u.c.s.t.) phase behaviour was found in blends of the homopolymer poly(oxy‐1,4‐phenyleneoxy‐1,4‐phenylenesulphonyl‐1,4‐phenylene) (PEES) with the copolymer poly(oxy‐l,4‐phenyleneoxy‐l,4‐phenylenecarbonyl‐l,4‐phenylene‐co‐oxy‐l,4‐phenyleneoxy‐1,4‐phenylenesul‐phonyl‐1,4‐phenylene) (COPEEKS) for copolymer compositions ranging from 43 mol% to 56 mol% of ether ether ketone (EEK) repeat units. Blend compositions studied ranged from 25wt% to 75wt% of PEES. The consolute temperature was found to occur at a PEES/COPEEKS blend composition of about 50/50 wt% and to increase with the EEK repeat unit content of the copolymer. This miscibility behaviour was interpreted, using a mean‐field theoretical approach, in terms of a single positive segmental interaction parameter which ranged from 0.054 to 0.032.
Synthesis and crosslinking of allyl polyarylmethylenes
Authors: Blincow Philip J. , Ghotra Joginder S. , Pritchard Geoffrey 
Published: April 2007

AbstractPolyarylmethylenes containing allyl unsaturation have been synthesised by the Friedel‐Crafts polymerisation of an allyl aromatic monomer and bis(methoxymethyl) benzene. The allyl groups do not take part in the Friedel‐Crafts polymerisation. The product can therefore be crosslinked through the allyl unsaturation thermally, or by heating with free radical or cationic initiators. The cationic crosslinking reaction appears to be the most convenient.
Ion‐matrix coupling in polymer electrolytes from relaxation time studies
Authors: Torell L. M. , Angell C. A. 
Published: April 2007

AbstractWe review the effects of temperature on conductance and viscosity in the liquid state of vitreous ionic conductors and show how differences may be best understood by comparison of relaxation times for electrical and mechanical stresses acting on liquid or glassy states of the material. This leads to the definition of a conductivity/viscosity mode decoupling index, useful as a figure of merit for the solid electrolyte. In applying the same approach to polymer electrolyte systems a problem is encountered due to the molecular weight dependence of the viscosity. This is resolved by deriving a ‘monomer’ shear relaxation time for the polymer electrolyte solution and showing that this quantity corresponds closely with the ‘local’ mechanical relaxation time obtained from light scattering studies (which is a molecular weight independent quantity for pure polypropylene oxide and other polymers of low Tg). Comparison of the electrical relaxation times of the polymer solution with the ‘local’ (or ‘matrix’) relaxation times then shows that the relationship found for superionic glass‐forming systems is inverted in the case of polymer electrolytes. The latter have fractional decoupling indexes which may be interpreted in terms of serial coupling phenomena; i.e. ions must first decouple from their partner ions (in ion pairs), or from their intramolecular solvation states, before they can contribute to conductivity relaxation which is itself coupled to the local polymer matrix relaxation. An extreme case is illustrated using the weak electrolyte, lithium acetate, for which the decoupling index is ∼6 × 10−5.
D.s.c., electrical conductivity, and n.m.r. studies of salt precipitation effects in PPO complexes
Authors: Wintersgill Mary C. , Fontanella John J. , Greenbaum Steven G. , Adamić Krešimir J. 
Published: April 2007

AbstractDifferential scanning calorimetry (d.s.c.) and electrical conductivity measurements of poly(propylene oxide), PPO, complexed with the salts NaI and KSCN are reported. In addition, 23Na n.m.r. measurements on PPO‐NaI (x = 8), both at ambient and elevated pressure (2 kbar), have been performed. The d.s.c. data clearly indicate that the salt precipitates out of the complexes at about 85°C for NaI and 60°C for KSCN. These effects are manifested by a dramatic departure of the conductivity from Vogel‐Tammann‐Fulcher (VTF) behaviour, and a relatively sharp drop in mobile Na+ concentration, as deduced from n.m.r. measurements, above about 80°C. High pressure n.m.r. linewidth measurements are consistent with a pressure‐induced increase in glass transition temperature.
Ion migration in liquid polymer electrolytes
Authors: Cameron G. Gordon , Harvie James L. , Ingram Malcolm D. , Sorrie Graham A. 
Published: April 2007

AbstractSolutions of alkali metal thiocyanates in liquid copolymers of ethylene oxide and propylene oxide provide a convenient medium for measuring conductivities, viscosities and transport numbers in polymer electrolytes by classical methods. The high value of the anion transport number (typically ca. 0.95) is noteworthy. A model, which emphasises the importance of intramolecular solvation of cations, the effects of ion pairing and redissociation, and the crosslinking action of anions at high salt concentrations, accounts satisfactorily for the properties of these liquid systems.
A mixed‐salt polyether electrolyte: PEOLiCF3SO3Nal
Authors: Maccallum James R. , Tomlin Anthony S. , Tunstall David P. , Vincent Colin A. 
Published: April 2007

AbstractConductivity and n.m.r. measurements are reported for three poly(ethylene oxide)‐inorganic salt complexes: PEO‐LiCF3SO3‐NaI ([EO]/[Li]/[Na] = 8/1/1), PEO‐LiCF3SO3 ([EO]/[Li] = 4), and PEO‐NaI ([EO]/[Na] = 4). The mixed‐salt system was shown to have a larger amorphous phase content than either of the single‐salt systems and more potential charge carriers. A dramatic effect upon the lithium motion and the microviscosity of the amorphous phase was noted upon the mixing of salts. It is proposed that some lithium ions are in environments of low symmetry, possibly of the ion‐pair type, and do not contribute to the n.m.r. signal. The recrystallisation behaviour of the mixed‐salt material was studied by the n.m.r. technique and an initial fast recrystallisation appears to be due to the formation of the high‐melting temperature phase.
Lithium/polymer electrolyte interfacial instability
Authors: Murugesamoorthi Kottuppulampalayam A. , Owen John R. 
Published: April 2007

AbstractThe stability of evaporated lithium with poly(ethylene oxide) (PEO), poly(propylene oxide) (PPO) and oxyethylene‐oxymethylene copolymer, doped with lithium perchlorate, in ultra‐thin‐film cells, was studied by impedance spectroscopy at room temperature. The formation and growth of a passivating film at the lithium/PEO interface has been observed, under open circuit conditions. The thickness of the passivating layer was estimated by assuming the dielectric constant of the interfacial product. A more extensive interfacial reaction was observed in the case of PPO. A very fast interfacial reaction was observed between lithium and amorphous copolymer.
Mesogenic structures and charge‐transfer reactions in poly(ethylene oxide) complexes
Authors: Mussarat Bushra , Conheeney Kevin , Siddiqui Jamil A. , Wright Peter V. 
Published: April 2007

AbstractAfter discussion of a schematic model for the crystalline phases of some poly(ethylene oxide) (PEO)‐Na+ complexes with organic anions, three types of material are discussed. (i) Complexes of sodium salts of organic acids substituted by hydrophobic groups are deposited from methanol as macrodomains of uniaxially oriented material; these rearrange to microdomain morphologies on heating above ca. 60°C. Similar anions substituted by polar groups form spherulitic complexes or they rearrange thermotropically to microdomain structures. (ii) The preparation of polythiocyanogen by a ‘canal’ polymerisation within a PEO‐NaSCN lattice is described and its extraction to give a material of conductivity ca. 10−1S cm−1 after doping is discussed, (iii) Charge‐transfer reactions with PEO‐NaI and tetracyano‐quinodimethan (TCNQ) to give films having conductivities of 10−3‐10Ω−1 cm−1 are also described.
New modifications of poly(vinyl alcohol)s and their applications
Authors: Maruyama Hitoshi , Moritani Tohei , Akazawa Toshiyuki , Sato Toshiaki 
Published: April 2007

AbstractPoly(vinyl alcohol) (PV‐OH), prepared from poly(viny) acetate), is used widely in many industries. Various grades have been produced, with different degree of polymerization and degree of hydrolysis. Recently, novel modified (PV‐OH)s with anion, cation, silanol or hydrophobic groups have been studied and developed. They have new properties in addition to those of ordinary PV‐OH and have new applications. The methods of modification and the characteristics and some applications of the modified polymers are described.
Thermoreversible gelation of solutions of poly(vinyl alcohol)
Authors: Stoks W. , Berghmans H. , Moldenaers P. , Mewis J. 
Published: April 2007

AbstractThe thermoreversible gelation of solutions of poly(vinyl alcohol) in ethylene glycol was investigated by calorimetric and optical observations, X‐ray scattering techniques and rheological measurements. The gelation that occurs on cooling to room temperature results from a liquid‐liquid demixing, followed by a crystallization of the polymer in the concentrated domains. As a consequence of the two‐phase morphology, practically no molecular orientation is observed when the gels are stretched. Gelation at high temperature, above the region of liquid‐liquid demixing, originates from a slow crystallization from solution. On stretching these gels, the crystallites orient their molecular axis perpendicular to the stretching direction and the (101) plane either parallel or perpendicular to the same direction. Rheological observations show that under no circumstances is a real network formed. The different gels studied resemble much more a stable colloidal dispersion with thixotropic properties.
Recent advances in thermosetting polyimides
Authors: Stenzenberger Horst 
Published: April 2007

AbstractAddition type imide resins are finding increased use as matrix resins for advanced composites. Many different chemical approaches have been used to synthesize imide resins which are easy to process (similar to epoxies) but higher in temperature resistance. This paper outlines recent advances in thermosetting imide resin chemistry; however, only those concepts which have been accepted by the industry and the most promising research concepts are discussed, such as:
endomethylenetetrahydrophthalimides
acetylene terminated polyimides
bismaleimides
benzocyclobutenes.
Of these, the bismaleimides are easiest to process. When used in combination with comonomers such as bisallylphenyl compounds, bis‐o‐(propenylphenoxy)‐benzophenones, benzocyclobutenes, etc., their toughness can be improved significantly to make them prime candidates as matrices for advanced composites and adhesives.
Water diffusion into rubber modified bismaleimide compositions
Authors: Tod David A. , Shaw Stephen J. 
Published: April 2007

AbstractThere has been considerable research into high temperature polymers in recent years and many novel systems have been synthesised. The requirements of high temperature resistance, resistance to moisture, and mechanical strength vie with each other in the selection of materials. In the defence field there are many applications for high temperature polymers, one of which is as high temperature adhesives. A particular problem with adhesives for defence use is that they need to withstand wide operating extremes both of temperature and humidity. A particular class of material that is suitable for high temperature adhesive application is the bismaleimides. The thermal resistance and strength of these materials has been established in previous studies. However, the effect of moisture upon these compositions has not been addressed. This paper covers aspects of diffusion of water into bismaleimide resin systems and is part of an ongoing research programme into high temperature polymers.
Conformational transition of poly(N‐vinylpyrrolidone) in aqueous solution of sodium decyl sulphate
Authors: de Sá Teresa García López 
Published: April 2007

AbstractThe intrinsic viscosity of four poly(N‐vinylpyrrolidone) fractions in the molecular weight range from 2.75 × 104 to 3.5 × 105 was measured in a cosolvent mixture of water/sodium decyl sulphate with different sodium decyl sulphate concentrations below its critical micellar concentration. Measurements were made in the temperature range 25−40°C.The value of the a and K parameters of the Mark‐Houwink‐Sakurada equation were determined. The values obtained for a were in general high, as expected for good solvents. Using the Stockmayer‐Fixman equation with the data, Kθ and B, i.e. the short and long range interaction parameters respectively, were calculated, which showed the existence of a conformational change at 12.3 mM sodium decyl sulphate concentration, at all temperatures.The polymer‐solvent interaction parameter X for the fraction of molar mass 3.5 × 105 was also determined.