bluuebunny/crossref_metadata_2025_split huggingface dataset:
Severe combined immunodeficiency and microcephaly in siblings with hypomorphic mutations in DNA ligase IV
Authors: Buck Dietke , Moshous Despina , de Chasseval Régina , Ma Yunmei , le Deist Françoise , Cavazzana‐Calvo Marina , Fischer Alain , Casanova Jean‐Laurent , Lieber Michael R. , de Villartay Jean‐Pierre 
Published: December 2005

AbstractDNA double‐strand breaks (dsb) during V(D)J recombination of T and B lymphocyte receptor genes are resolved by the non‐homologous DNA end joining pathway (NHEJ) including at least six factors: Ku70, Ku80, DNA‐PKcs, Artemis, Xrcc4, and DNA ligase IV (Lig4). Artemis and Lig4 are the only known V(D)J/NHEJ factors found deficient in human genetic disorders. Null mutations of the Artemis gene result in a complete absence of T and B lymphocytes and increased cellular sensitivity to ionizing radiations, causing radiosensitive‐SCID. Mutations of Lig4 are exclusively hypomorphic and have only been described in six patients, four exhibiting mild immunodeficiency associated with microcephaly and developmental delay, while two patient had leukemia. Here we report a SCID associated with microcephaly caused by compound heterozygous hypomorphic mutations in Lig4. Residual activity of Lig4 in these patients is underscored by a normal pattern of TCR‐α and ‐β junctions in the T cells of the patients and a moderate impairment of V(D)J recombination as tested in vitro. These observations contrast with the severity of the clinical immunodeficiency, suggesting that Lig4 may have additional critical roles in lymphocyte survival beyond V(D)J recombination.
Self‐Assembly of a Tetranuclear CoIII‐Metallacycle from the Reaction of a Bis(benzene‐o‐dithiolato) Ligand with CoIIand Subsequent Aerial Oxidation
Authors: Hahn F. Ekkehardt , Kreickmann Thorsten , Pape Tania 
Published: December 2005

AbstractThe bis(benzene‐o‐dithiol) ligand [(HS)2‐2,3‐C6H3–CH2–C6H3‐2,3‐(SH)2] (H4‐1) reacts, after deprotonation with Li2CO3, with CoCl2·6H2O. Aerial oxidation in methanol gives the tetranuclear metallacycle Li4[Co4(1)4]. The X‐ray structure analysis of (PNP)4[Co4(1)4] (7) reveals a cyclic structure in which each of the bis(benzene‐o‐dithiolato) ligands forms a bridge between two cobalt centers. Two differently coordinated cobalt atoms (synandanti) are observed in the tetranuclear complex. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Mutations in mitochondrial‐encoded cytochrome c oxidase subunits I, II, and III genes detected in Alzheimer's disease using single‐strand conformation polymorphism
Authors: Hamblet Natasha S. , Ragland Brian , Ali Mervat , Conyers Barbara , Castora Frank J. 
Published: December 2005

AbstractA “mitochondrial hypothesis” of late onset Alzheimer's disease (AD) has been proposed. Biochemical studies indicate that there is a significant decrease in cytochrome oxidase (CO) activity as well as perturbed CO I and CO III mRNA levels in platelets and brain tissue from Alzheimer's patients. Using the electrophoretic mutation detection technique SSCP and DNA sequencing, we have identified 20 point mutations in the mitochondrial‐encoded CO subunits (CO I, II, and III) in AD and age‐matched control brain samples. Eight of the mutations are new variants of the mitochondrial genome. The efficiency of SSCP in detecting mutations in the CO subunits was estimated to be 80% when compared to dideoxy sequencing. One of the mutations (at position 9861) results in a phenylalanine→leucine substitution at a highly conserved residue in CO III. CO activity was reduced by an average of 35% in all AD brains compared to age‐matched control samples, which agrees with previous reports. CO activity in one of the AD brain samples carrying the 9861 mutation decreased by 80% relative to control brain samples, suggesting that the phenotypic expression of this mutation may result in reduced CO activity and compromised mitochondrial function.
Sustained‐release delivery systems of triclosan for treatment of Streptococcus mutans biofilm
Authors: Steinberg Doron , Tal Tamir , Friedman Michael 
Published: December 2005

AbstractDental diseases are chronic infections caused by oral bacteria harboring the dental biofilm. Local sustained‐release delivery systems prolong the duration of a drug in the oral cavity, thus enhancing its therapeutic potential, while reducing its side effects. Triclosan is an agent that was found to have an antibacterial effect against oral bacteria. However, its substantivity in the oral cavity is low, resulting in reduced antibacterial efficiency. The purpose of this study was to develop a local sustained release device containing triclosan and to test its antibacterial efficacy on Streptococcus mutans biofilm. Our results show that we can formulate an ethylcellulose‐based, nondegradable, sustained‐release device in which 80% of the loaded triclosan is released over a 10‐day period. The release rate of triclosan corresponded to the Higuchi's planar homogenous diffusion release model (r2 = 0.998). A degradable local sustained‐release delivery based on a methacrylate ester matrix was also developed for a faster release rate of triclosan. The release kinetics in those types of sustained‐release delivery systems was erosion control. The local sustained‐release delivery system significantly affected the viability of S. mutans in biofilm compared to placebo as was tested by confocal laser scanning microscopy. Our in vitro results show that triclosan can be incorporated into degradable or nondegradable sustained‐release drug delivery systems. The release of triclosan from the local sustained‐release delivery system can be controlled, thus extending its antibacterial properties. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
First steps towards tissue engineering of small‐diameter blood vessels: Preparation of flat scaffolds of collagen and elastin by means of freeze drying
Authors: Buttafoco L. , Engbers‐Buijtenhuijs P. , Poot A. A. , Dijkstra P. J. , Daamen W. F. , van Kuppevelt T. H. , Vermes I. , Feijen J. 
Published: December 2005

AbstractPorous scaffolds composed of collagen or collagen and elastin were prepared by freeze drying at temperatures between –18 and –196°C. All scaffolds had a porosity of 90–98% and a homogeneous distribution of pores. Freeze drying at –18°C afforded collagen and collagen/elastin matrices with average pore sizes of 340 and 130 μm, respectively. After 20 successive cycles up to 10% of strain, collagen/elastin dense films had a total degree of strain recovery of 70% ± 5%, which was higher than that of collagen films (42% ± 6%). Crosslinking of collagen/elastin matrices either in water or ethanol/water (40% v/v) was carried out using a carbodiimide (N‐(3‐dimethylaminopropyl)‐N′‐ethylcarbodiimide hydrochloride, EDC) in combination with a succinimide (N‐hydroxysuccinimide, NHS) in the presence or absence of a diamine (J230) or by reaction with butanediol diglycidylether (BDGE), followed by EDC/NHS. Crosslinking with EDC/NHS or EDC/NHS/J230 resulted in matrices with increased stiffness as compared to noncrosslinked matrices, whereas sequential crosslinking with the diglycidylether and EDC/NHS yielded very brittle scaffolds. Ethanol/water was the preferred solvent in the crosslinking process because of its ability to preserve the open porous structure during crosslinking. Smooth muscle cells were seeded on the (crosslinked) scaffolds and could be expanded during 14 days of culturing. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
In vivo performance of two different hydroxyapatite coatings on titanium prepared by discharging in electrolytes
Authors: Yamamoto Hiroki , Shibata Yo , Tachikawa Tetsuhiko , Miyazaki Takashi 
Published: December 2005

AbstractThis study reports a discharging method for bone‐like carbonated HA (cHA)‐coating (Ca/P 1.71) and stoichiometric HA (sHA)‐coating (Ca/P 1.67) with micrometer order thicknesses on titanium plates, using modified body fluid and acidic calcium phosphate solutions, respectively. In vivo histological performance of the HA coatings prepared by discharging in electrolytes was evaluated. Bone‐contact indexes of HA coatings were measured microscopically. Additionally, bone‐coating interface was analyzed by scanning electron microscopy and the use of an electron probe microanalyzer. Results demonstrated that there was no significant difference in contact index between HA coatings. However, the cHA coating was practically replaced by immature bone, and the titanium metal substrate was directly connected to the bone structure whereas the sHA coating layer remained and was partially detached from the titanium metal substrate. Since detached coating particles are pathogens, and can cause peri‐implantitis, the cHA coating was more favorable than the sHA coating even if contact index was equivalent to that of the sHA coating. It is thought that coating thickness and chemical composition of coatings are important for biological stability of implants. In conclusion, since bone‐like thin cHA coating showed high osteoconductivity and bone replacement, bone‐like HA is superior to sHA coating for use in dental implants. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Effects of additives on the rheological properties and injectability of a calcium phosphate bone substitute material
Authors: Wang Xiupeng , Ye Jiandong , Wang Hai 
Published: December 2005

AbstractAn injectable calcium phosphate bone substitute material has been prepared by mixing amorphous calcium phosphate (ACP) and dicalcium phosphate dihydrate (DCPD) for use in noninvasive surgery, and the influence of additives, such as disodium hydrogen phosphate, polyethylene glycol (PEG), glycerin, and citric acid, on the rheological properties and injectability of the ACP + DCPD cement system have been studied in this work. Novel approach of thixotropy measurement has been used to characterize the stability of the pastes. The results show that the injectability and the setting time can be augmented by the addition of disodium phosphate solution to the paste but reduced by the addition of PEG 200, glycerin, or citric acid to the paste. This study suggests that the injectability and the setting time of the ACP + DCPD bone substitute material can be balanced, and the injectable calcium phosphate bone substitute material with satisfied fluidity and injectability for clinical operation can be prepared by optimizing the additives and their concentrations, according to different clinical requirements. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Hydrogen absorption of titanium and nickel‐titanium alloys during long‐term immersion in neutral fluoride solution
Authors: Yokoyama Ken'ichi , Ogawa Toshio , Asaoka Kenzo , Sakai Jun'ichi 
Published: December 2005

AbstractHydrogen absorption of biomedical titanium and Ni‐Ti alloys in a neutral fluoride (2.0% NaF) solution for up to 10,000 h at 37°C has been evaluated by means of hydrogen thermal desorption analysis. For α titanium (commercial pure titanium), the amount of absorbed hydrogen was, at most, 10–30 mass ppm, and the corrosion product and hydride formation were revealed on the surface of the specimen by X‐ray diffraction analysis. Ni‐Ti superelastic alloy absorbed ∼150 mass ppm of hydrogen, which was probably sufficient to result in the pronounced degradation of the mechanical properties, although corrosion was hardly observed. In contrast, hydrogen absorption of α‐β titanium (Ti‐6Al‐4V) and β titanium (Ti‐11.3Mo‐6.6Zr‐4.3Sn) alloys was negligible, although general corrosion was observed. The results of the present study indicate that the susceptibility of titanium and Ni‐Ti alloys to hydrogen absorption in the neutral fluoride solution is different from that in the acidic fluoride solution reported previously. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Adsorption of biometals to monosodium titanate in biological environments
Authors: Hobbs D. T. , Messer R. L. W. , Lewis J. B. , Click D. R. , Lockwood P. E. , Wataha J. C. 
Published: December 2005

AbstractMonosodium titanate (MST) is an inorganic sorbent/ion exchanger developed for the removal of radionuclides from nuclear wastes. We investigated the ability of MST to bind Cd(II), Hg(II), Au(III), or the Au‐organic compound auranofin to establish the utility of MST for applications in environmental decontamination or medical therapy (drug delivery). Adsorption isotherms for MST were determined at pH 7–7.5 in water or phosphate‐buffered saline. The extent of metal binding was determined spectroscopically by measuring the concentrations of the metals in solution before and after contact with the MST. Cytotoxic responses to MST were assessed using THP1 monocytes and succinate dehydrogenase activity. Monocytic activation by MST was assessed by TNFα secretion (ELISA) with or without lipopolysaccharide (LPS) activation. MST adsorbed Cd(II), Hg(II), and Au(III) under conditions similar to those in physiological systems. MST exhibited the highest affinity for Cd(II) followed by Hg(II) and Au (III). MST (up to 100 mg/L) exhibited only minor (<25% suppression of succinate dehydrogenase) cytotoxicity and did not trigger TNFα secretion nor modulate LPS‐induced TNFα secretion from monocytes. MST exhibits high affinity for biometals with no significant biological liabilities in these introductory studies. MST deserves further scrutiny as a substance with the capacity to decontaminate biological environments or deliver metals or metal compounds for therapeutic applications. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
On fans in multigraphs
Authors: Cariolaro David 
Published: December 2005

AbstractWe introduce a unifying framework for studying edge‐coloring problems on multigraphs. This is defined in terms of a rooted directed multigraph $\cal F$, which is naturally associated to the set of fans based at a given vertex u in a multigraph G. We call $\cal F$ the “Fan Digraph.” We show that fans in G based at u are in one‐to‐one correspondence with directed trails in $\cal F$ starting at the root of $\cal F$. We state and prove a central theorem about the fan digraph, which embodies many edge‐coloring results and expresses them at a higher level of abstraction. Using this result, we derive short proofs of classical theorems. We conclude with a new, generalized version of Vizing's Adjacency Lemma for multigraphs, which is stronger than all those known to the author. © 2005 Wiley Periodicals, Inc. J Graph Theory 51: 301–318, 2006
Allele C‐specific methylation of the 5‐HT2A receptor gene: Evidence for correlation with its expression and expression of DNA methylase DNMT1
Authors: Polesskaya Oxana O. , Aston Christopher , Sokolov Boris P. 
Published: December 2005

AbstractDifferential DNA methylation has been suggested to contribute to differential activity of alleles C and T and thereby to genetic associations between the C/T(102) polymorphism in the 5‐HT2A receptor gene (5HT2AR) and psychiatric disorders. We surveyed methylation in two CpG sites, which are specific to allele C. The majority of allele C‐specific CpG sites were methylated in human temporal cortex and peripheral leukocytes and levels of methylation varied between individuals. Levels of methylation in the promoter correlated significantly with the expression of 5HT2AR. Methylation of allele C‐specific CpG sites in the first exon correlated significantly with the expression of DNA methylase 1 (DNMT1) but not S‐adenosylhomocysteine hydrolase (AHCY). These findings support the hypothesis that allele‐specific DNA methylation is involved in regulation of 5HT2AR expression, influencing expression differences between alleles C and T. © 2005 Wiley‐Liss, Inc.
The measurement of tourist destination image: applying a sketch map technique
Authors: Son Aram 
Published: December 2005

AbstractThis study was conducted in order to identify the images of two Australian cities, Sydney and Melbourne, held by international students on English language programmes. It used a sketch‐map methodology supplemented by a range of question types and styles. The results were analysed based on 115 completed questionnaires distributed to international students at Holmes College, an English language teaching institution with campuses in both Melbourne and Sydney. The results of the sketch maps of the two cities indicated that Sydney is perceived as a spatially dominated city, whereas Melbourne is seen as a path orientated city. The study confirmed that a sketch map technique could be used as an alternative or supplementary method to measure tourists' spatial orientation in a tourist destination. Copyright © 2005 John Wiley & Sons, Ltd.
Perceptions of foreign tourists by local service providers: the case of Fethiye, Turkey
Authors: Kozak Metin , Tasci Asli D. A. 
Published: December 2005

AbstractA substantial amount of research has been carried out on foreign tourists' perceptions of the attitude and behaviour of locals. However, locals' perceptions of foreign tourists' attitude and behaviour has not received as much attention from researchers. The aim of this study was to empirically investigate the locals' perceptions of attitude and behaviour of those foreign tourists who regularly visit a destination. The study was undertaken on various local service providers in the tourism and hotel industry, such as hotels, restaurants, travel agencies and gift shops in the central part of Fethiye, a popular tourist town in southwest Turkey. Using both open‐ended and structured questions, locals' perceptions of two nationalities of foreign tourists, namely British and Germans, were measured. Findings revealed that, overall British tourists were viewed as more positive than their German counterparts. Theoretical and practical implications are provided, followed by limitations and future research suggestions. Copyright © 2005 John Wiley & Sons, Ltd.
Clustering of Chinese tourists to Singapore: an analysis of their motivations, values and satisfaction
Authors: Kau Ah Keng , Lim Pei Shan 
Published: December 2005

AbstractThis paper presents the findings of a survey through the use of a structured questionnaire of over 240 visitors from China to Singapore in February 2003. The main objective is to determine if these tourists could be effectively segmented based on their motivations for travel. The analysis of the survey data confirmed that they could be clustered into four main segments. Each of the segments was found to possess unique profiles in terms of demographic background, trip‐related characteristics and personal values. The segments were also assessed of their levels of satisfaction with various attributes offered by Singapore as a tourist destination. In addition, their overall satisfaction, likelihood of revisit and likelihood of making positive word‐of‐mouth recommendation to others were also determined. In all of these, the segments were found to differ significantly from each other. Finally, the implications of these findings were discussed and suggestions made as to how Singapore could effectively develop marketing strategies to attract these tourists, bearing in mind that China was the third largest tourist generating country for Singapore and they collectively contributed over S$300 million to the Singapore economy in 2002. In fact, tourist arrival from China increased further after SARS in 2003, reaching over 880,000 in 2004 and became the second largest tourist group after Indonesia. Copyright © 2005 John Wiley & Sons, Ltd.
Pd(II)‐catalyzed polymerization of optically active norbornene carboxylic acid esters
Authors: Byun Gwang‐Su , Kim Sang Youl , Cho Iwhan 
Published: December 2005

Abstract(−)‐(1S,2R)‐Norbornene‐2‐carboxylic acid alkyl esters (alkyl = Me, Bz, L‐menthyl, or D‐menthyl) were successfully prepared by the Diels–Alder reaction of cyclopentadiene with (R)‐(−)‐pantolactone‐O‐yl acrylate followed by epimerization and column chromatography. The enantiomeric excess was 99.9%. These monomers were polymerized by Pd(II)‐based catalysts, and high yields of the polymers were obtained. The methyl ester gave an optically active polymer of high optical rotation (monomer [α]D = −24.7, polymer [α]D = −98.5). This high rotation value of the polymer was attributed to the isotactic chain regulation of the polymer. This high rotation was not observed with methyl esters prepared by the transesterification of menthyl esters. The stereoregular polymer exhibited notable resonance peaks at 39 ppm in 13C NMR spectra. No crystallinity was observed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1263–1270, 2006
Synthesis, characterization, and thermal properties of a novel pentaerythritol‐initiated star‐shaped poly(p‐dioxanone)
Authors: Huang Hai‐Xia , Yang Ke‐Ke , Wang Yu‐Zhong , Wang Xiu‐Li , Li Jun 
Published: December 2005

AbstractA novel star‐shaped poly(p‐dioxanone) was synthesized by the ring‐opening polymerization of p‐dioxanone initiated by pentaerythritol with stannous octoate as a catalyst in bulk. The effect of the molar ratio of the monomer to the initiator on the polymerization was studied. The polymers were characterized with 1H NMR and 13C NMR spectroscopy. The thermal properties of the polymers were investigated with differential scanning calorimetry and thermogravimetric analysis. The novel star‐shaped poly(p‐dioxanone) has a potential use in biomedical materials. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1245–1251, 2006
Ethylene/vinyl acetate copolymer/clay nanocomposites
Authors: Srivastava S. K. , Pramanik M. , Acharya H. 
Published: December 2005

AbstractThis article highlights the history, synthetic routes, material properties, and scope of ethylene/vinyl acetate copolymer (EVA)/clay nanocomposites. These nanocomposites of EVAs are achieved with either unmodified or organomodified layered silicates with different methods. The structures of the resulting polymer/inorganic nanocomposites have been characterized with X‐ray diffraction, scanning electron microscopy, and transmission electron microscopy. The addition of a small amount of clay, typically less than 8 wt %, to the polymer matrix unusually promotes the material properties, such as the mechanical, thermal, and swelling properties, and increases the flame retardancy of these hybrids. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 471–480, 2006
Effect of soft segment component on moisture‐permeable polyurethane films
Authors: Shibaya Miaki , Suzuki Yosuke , Doro Mutsuko , Ishihara Hideaki , Yoshihara Nori , Enomoto Masao 
Published: December 2005

AbstractThe effect of soft segment component and molecular weight combination on moisture‐permeable polyurethane films was studied. Moreover, water sorption phenomenon in films was observed with infrared analysis. As for soft segment components, PTMG/PEG and PTMG/PPG were used and molecular weight combinations were changed. Different tendency appeared in the experimental results corresponding to PEG system and PPG system. Moisture permeability P in PEG system increased with increasing PEG content, but P changed little in the case of PPG system. Both hydrogen‐bonded concentration by infrared measurement and the higher order term Δh of Mooney–Rivlin plot by stress–strain relationships indicate the existence of aggregate structure of hard segment. It is considered that ether group in PEG is more active than that in PPG. Therefore, small size of aggregate structure indicated as Δh appears in PEG system owing to inhibition of aggregate structure growth. Whereas, ether group in PPG system does not inhibit hydrogen bond in urethane group and large size of aggregate structure appears. From water affinity relationship analysis, hydrophilicity of samples with PTMG/PEG = 2000/2000 increased with increasing PEG content. Consequently, it is suggested that not only size but also hydrogen‐bonded concentration of urethane group in aggregate structure affects moisture permeability. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 573–583, 2006