bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biological evaluation of a new organically modified ceramic‐based dental restorative resin
Authors: Lizymol P. P. , Mohanan P. V. , Sabareeswaran A. , Krishnan V. Kalliyana 
Published: December 2011

AbstractMaterial tissue interactions of a newly developed organically modified ceramic (ormocer)‐based dental restorative composite based on a resin containing mixture of alkoxides of silicone and calcium with polymerizable methacrylate end groups are discussed in this study. Admira, a commercially available ormocer was used as control. A sol–gel process has been used to synthesize organically modified ceramic resins from liquid precursors, which allow one to produce inorganic–organic hybrid polymer materials, which can be functionalized to optimize their physical and chemical properties. Besides, the resulting material properties have been significantly modified by further technological processing such as photochemical curing of the materials by incorporating dimethacrylate groups as organically polymerizable units. Intracutaneous (intradermal) irritation test is found not to elicit any gross signs of tissue reaction. The results of maximization test for delayed hypersensitivity also did not show any adverse skin reaction during the induction or challenge period. Histological analysis after 1, 4, and 12 weeks of subcutaneous implantation of restorative composite resin on the dorsal surface on one side of the spinal column of Wister rats is also found not to reveal any inflammatory response after the implantation. Granuloma and material debris is found to be absent in all three periods of implantation in both test and control. No necrosis was observed around the implanted materials, which were found to be encapsulated by fibrous connective tissue consisting of predominantly fibroblasts and inflammatory cells. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Curing behaviors and properties of novolac/bisphthalonitrile blends
Authors: Guo Heng , Lei Yajie , Zhao Xin , Yang Xulin , Zhao Rui , Liu Xiaobo 
Published: December 2011

AbstractBisphthalonitrile (BAPh) monomer was blended with novolac resins to achieve good processing resin blends. The curing behaviors of the novolac/BAPh (novolac/BAPh) blends were studied by differential scanning calorimetry (DSC) and dynamic rheological analysis. The results indicated that the blends had large processing windows (98–118°C), and they can copolymerize without any other curing additives. The novolac/BAPh copolymers were obtained by short curing times and low curing temperatures. Thermal and thermal‐oxidative stabilities of the copolymers were investigated by thermal gravimetric analysis, and the char yields up to 74 and 35% by weight at 800°C were achieved under nitrogen and air atmosphere, respectively. These postcured copolymers exhibited a 5% weight loss temperature of 502°C in air. These results revealed that the copolymers exhibited excellent thermal and thermal‐oxidative stabilities. Dynamic mechanical properties of the copolymers were systematically evaluated by dynamic mechanical analysis. The copolymers exhibited higher glass transition temperatures (Tg) as the BAPh content increased. Mechanical properties of the copolymers were investigated, and these data showed that flexural strength and flexural modulus of the 50 : 50 novolac/BAPh copolymers were 91 MPa and 5.78 GPa, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Molecular Mechanism of Remodeling of Autologous Artery Graft Interposed to Vein in Rabbit
Authors: Feng Yanling , Shen Yanguo , Zhang Hongqi 
Published: December 2011

AbstractOur previous study found that the artery interposed to vein did not develop atherosclerosis but rather underwent atrophic remodeling in hyperlipidemic rabbits, suggesting that local hemodynamic load was another important determinant for the development of atherosclerosis. This study focused on the cellular and molecular changes in autologous artery grafts derived from rabbits fed with high lipid diet for 1, 2, 4, 8, and 12 weeks. Thickness, area of vessel wall, and lumen area were measured and analyzed on the grafted common carotid artery (GCCA) interposed to vein and on the right common carotid artery. Apoptosis was detected by terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end‐labeling. Both elastin and collagen of GCCA were identified by the method of double stains of elastin and collagen. Reverse transcription polymerase chain reaction was used to observe matrix metalloproteinases (MMPs) mRNA expression changes in the examined arteries. The lumen area increased gradually in control common carotid artery and remained unchanged in GCCA 3 months later, since the surgery and the start of high lipid diet, while significantly increased apoptosis was evidenced from inner to outer part of GCCA. Collagen content decreased gradually and elastic fibers remained unchanged in GCCA. At 1 week after operation, the mRNA expression of MMP2 and MMP9 increased significantly and returned to baseline thereafter. The artery interposed to a vein underwent atrophy, characterized by increased apoptosis in the vessel wall from intima to adventitia, possibly due to low shear stress circumference and reduced vessel collagen resulting from postsurgical upregulated MMP2 and MMP9 expression. Anat Rec,, 2012. © 2011 Wiley Periodicals, Inc.
Risk factors for magnetic resonance imaging–detected patellofemoral and tibiofemoral cartilage loss during a six‐month period: The Joints On Glucosamine study
Authors: Roemer Frank W. , Kwoh C. Kent , Hannon Michael J. , Green Stephanie M. , Jakicic John M. , Boudreau Robert , Crema Michel D. , Moore Carolyn E. , Guermazi Ali 
Published: December 2011

AbstractObjectiveTo assess several baseline risk factors that may predict patellofemoral and tibiofemoral cartilage loss during a 6‐month period.MethodsFor 177 subjects with chronic knee pain, 3T magnetic resonance imaging (MRI) of both knees was performed at baseline and followup. Knees were semiquantitatively assessed, evaluating cartilage morphology, subchondral bone marrow lesions, meniscal morphology/extrusion, synovitis, and effusion. Age, sex, and body mass index (BMI), bone marrow lesions, meniscal damage/extrusion, synovitis, effusion, and prevalent cartilage damage in the same subregion were evaluated as possible risk factors for cartilage loss. Logistic regression models were applied to predict cartilage loss. Models were adjusted for age, sex, treatment, and BMI.ResultsSeventy‐nine subregions (1.6%) showed incident or worsening cartilage damage at followup. None of the demographic risk factors was predictive of future cartilage loss. Predictors of patellofemoral cartilage loss were effusion, with an adjusted odds ratio (OR) of 3.5 (95% confidence interval [95% CI] 1.3–9.4), and prevalent cartilage damage in the same subregion with an adjusted OR of 4.3 (95% CI 1.3–14.1). Risk factors for tibiofemoral cartilage loss were baseline meniscal extrusion (adjusted OR 3.6 [95% CI 1.3–10.1]), prevalent bone marrow lesions (adjusted OR 4.7 [95% CI 1.1–19.5]), and prevalent cartilage damage (adjusted OR 15.3 [95% CI 4.9–47.4]).ConclusionCartilage loss over 6 months is rare, but may be detected semiquantitatively by 3T MRI and is most commonly observed in knees with Kellgren/Lawrence grade 3. Predictors of patellofemoral cartilage loss were effusion and prevalent cartilage damage in the same subregion. Predictors of tibiofemoral cartilage loss were prevalent cartilage damage, bone marrow lesions, and meniscal extrusion.
Sunitinib inhibits the phosphorylation of platelet‐derived growth factor receptor β in the skin of mice with scleroderma‐like features and prevents the development of the disease
Authors: Kavian Niloufar , Servettaz Amélie , Marut Wioleta , Nicco Carole , Chéreau Christiane , Weill Bernard , Batteux Frédéric 
Published: December 2011

AbstractObjectiveSystemic sclerosis (SSc) is characterized by fibrosis of the skin and visceral organs, vascular dysfunction, and immunologic dysregulation. Platelet‐derived growth factors (PDGFs) have been implicated in the development of fibrosis and dysregulation of vascular function. We investigated the effects of sunitinib and sorafenib, two tyrosine kinase inhibitors that interfere with PDGF signaling, in a mouse model of diffuse SSc.MethodsSSc was induced in BALB/c mice by subcutaneous injections of HOCl daily for 6 weeks. Mice were randomized to treatment with sunitinib, sorafenib, or vehicle. The levels of native and phosphorylated PDGF receptor β (PDGFRβ) and vascular endothelial growth factor receptor (VEGFR) in the skin were assessed by Western blot and immunohistochemical analyses. Skin and lung fibrosis were evaluated by histologic and biochemical methods. Autoantibodies were detected by enzyme‐linked immunosorbent assay, and spleen cell populations were analyzed by flow cytometry.ResultsPhosphorylation of PDGFRβ and VEGFR was higher in fibrotic skin from HOCl‐injected mice with SSc than from PBS‐injected mice. Injections of HOCl induced cutaneous and lung fibrosis, increased the proliferation rate of fibroblasts in areas of fibrotic skin, increased splenic B cell and T cell counts, and increased anti–DNA topoisomerase I autoantibody levels in BALB/c mice. All of these features were reduced by sunitinib but not by sorafenib. Sunitinib significantly reduced the phosphorylation of both PDGF and VEGF receptors.ConclusionInhibition of the hyperactivated PDGF and VEGF pathways by sunitinib prevented the development of fibrosis in HOCl‐induced murine SSc and may represent a new SSc treatment for testing in clinical trials.
Assessments of growth conditions on the production of cyanophycin by recombinant Escherichia coli strains expressing cyanophycin synthetase gene
Authors: Tseng Wen‐Chi , Fang Tsuei‐Yun , Cho Chiung‐Yu , Chen Po‐Shao , Tsai Ching‐Shiang 
Published: December 2011

AbstractThe synthesis of cyanophycin, a biodegradable polymer, is directed by cyanophycin synthetase. Polymerase chain reaction (PCR) cloned the gene cphA coding for cyanophycin synthetase from Synechocystis sp. PCC 6803 into pET‐21b followed by transformation into two Escherichia coli hosts. The culture conditions for cyanophycin production were investigated, and the molecular weight and compositions of purified cyanophycin were analyzed. The results showed that E. coli BL21‐CodonPlus(DE3)‐RIL could produce 120 mg cyanophycin per gram dry cell weight in terrific medium. The purified cyanophycin consisted of insoluble and soluble forms at pH 7. The insoluble form had a higher molecular weight (20–32 kDa) than the soluble form (14–25 kDa). Both forms are composed of three major amino acids, aspartic acid, arginine, and lysine, and the insoluble form showed a higher arginine/lysine molar ratio (4.61 ± 0.31) than the soluble form (0.89 ± 0.05). In addition, the nitrogen sources could affect the yields of insoluble and soluble forms of cyanophycin. The medium containing additional lysine could enhance the proportion of the soluble form, but had little effect on the lysine and arginine percentages of both soluble and insoluble forms. The medium containing additional arginine slightly decreased the proportion of soluble form and altered its amino acid composition, with a minimal effect on the lysine and arginine percentages in the insoluble form. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Eliminating the six N‐terminal amino acids of the caspase 3 large subunit improved production of a biologically active IL2‐Caspase3 chimeric protein
Authors: Glantz Yitav , Sabag Ofra , Lichtenstein Michal , Grodzovski Inna , Lorberboum‐Galski Haya 
Published: December 2011

AbstractDesigning a chimeric protein and developing a procedure for its stable production as a biologically active protein, are key steps in its potential application to clinical trails. IL2‐Caspase3 chimeric protein designed to target activated T lymphocytes was found to be a promising molecule for targeted treatment, however was found to be difficult to produce as a biological active molecule. Thus, we designed a new version of the molecule, IL2‐Caspase3s, in which six amino acids (aa 29–34) from the N‐terminus of the large subunit of caspase 3 were excluded. Repeated expressions, productions, and partial purifications of the IL2‐Caspase3s yielded reproducible batches with consistent results. We found that IL2‐Caspase3s causes cell death in a specific, dose‐, and time‐dependent manner. Cell death due to IL2‐Caspase3s is caused by apoptosis. This improved and biologically stable IL2‐Caspase3s chimeric protein may be developed in the future for clinical trails as a promising therapy for several pathologies involving activated T‐cells. Moreover, this truncated caspase 3 sequence, lacking the N‐terminal six amino acids of its large subunit, may be used in other caspase 3‐based chimeric proteins targeted against various human diseases, using the appropriate targeting moiety. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Development of FRET‐Based Dual‐Excitation Ratiometric Fluorescent pH Probes and Their Photocaged Derivatives
Authors: Yuan Lin , Lin Weiying , Cao Zengmei , Wang Jiaoliang , Chen Bin 
Published: December 2011

AbstractDual‐excitation ratiometric fluorescent probes allow the measurement of fluorescence intensities at two excitation wavelengths, which should provide a built‐in correction for environmental effects. However, most of the small‐molecule dual‐excitation ratiometric probes that have been reported thus far have shown rather limited separation between the excitation wavelengths (20–70 nm) and/or a very small molar absorption coefficient at one of the excitation wavelengths. These shortcomings can lead to cross‐excitation and thus to errors in the measurement of fluorescence intensities and ratios. Herein, we report a FRET‐based molecular strategy for the construction of small‐molecule dual‐excitation ratiometric probes in which the donor and acceptor excitation bands exhibit large separations between the excitation wavelengths and comparable excitation intensities, which is highly desirable for determining the fluorescence intensities and signal ratios with high accuracy. Based on this strategy, we created a coumarin–rhodamine FRET platform that was then employed to develop the first class of FRET‐based dual‐excitation ratiometric pH probes that have two well‐resolved excitation bands (excitation separations>160 nm) and comparable excitation intensities. In addition, these pH probes may be considered as in a kind of “secured ratioing mode”. As a further application of these pH probes, the dual‐excitation ratiometric pH probes were transformed into the first examples of photocaged dual‐excitation ratiometric pH probes to improve the spatiotemporal resolution. It is expected that the modular nature of our FRET‐based molecular strategy should render it applicable to other small‐molecule dual‐dye energy‐transfer systems based on diverse fluorescent dyes for the development of a wide range of dual‐excitation ratiometric probes with outstanding spectral features, including large separations between the excitation wavelengths and comparable excitation intensities.
A Versatile Thiouronium‐Based Solid‐Phase Synthesis of 1,3,5‐Triazines
Authors: Kong Kah Hoe , Tan Chong Kiat , Lin Xijie , Lam Yulin 
Published: December 2011

AbstractA thiouronium‐based solid‐phase synthesis of a 1,3,5‐triazine scaffold has been developed. The key feature of the synthesis is the use of a readily accessible solid‐supported thiouronium salt as a primary precursor for the stepwise assembly of the 1,3,5‐triazine substrate. The sulfur linker employed in the synthesis is stable under both acidic and basic conditions and is versatile enough to provide access to monocyclic, bicyclic, and spirocyclic compounds with the 1,3,5‐triazine scaffold. By using this synthetic strategy, a representative set of 79 compounds containing the 1,3,5‐triazine scaffold were prepared.
Study of pressure fluctuations in an internal loop airlift bioreactor
Authors: Luo Lijia , Yan Ying , Xu Yuanyuan , Xie Ping , Sun Junwei , Guo Wei , Yuan Jingqi 
Published: December 2011

AbstractThe origin and coupling of pressure fluctuations in an internal loop airlift bioreactor are investigated. The pressure fluctuations in the reactor are divided into two categories: global pressure fluctuations and local pressure fluctuations. It is found that the coupling between global pressure fluctuations and local pressure fluctuations mainly focuses in the frequency region between 10 and 30 Hz. Local pressure fluctuations in the reactor are strongly affected by pressure waves originating from the air‐supply system, while pressure fluctuations caused by the bubble eruption at the liquid surface have less influence on local pressure fluctuations. Based on the coherence analysis, the pressure signal at a certain position in the reactor is decomposed into three different parts: coherent part, joint incoherent part and exclusive incoherent part. The energy ratios of these different parts are helpful to study the interaction among pressure fluctuations from different sources. Three flow regimes were identified from the evolution of the energy ratio of the joint incoherent part. © 2011 Canadian Society for Chemical Engineering
Design of a micro glass cell apparatus for pure gas‐nonvolatile liquid phase behaviour study
Authors: Foroughi Hooman , Acosta Edgar J. , Kawaji Masahiro 
Published: December 2011

AbstractA micro syringe is used as a constant volume cell for gas–liquid equilibrium (GLE) study. The cell is made of glass and has a volume of <100 µL. It can operate at pressures up to 13 MPa and temperatures up to 115°C. Two different experimental procedures are presented for systems with nonvolatile low and high viscosity liquids. A micro magnetic stir bar is used to mix the gas–liquid mixtures inside the cell. Since the internal volume of the cell is small, a short mixing time is sufficient for the gas–liquid mixtures to reach equilibrium. The solubility values are measured by using the pressure decay method. The experimental procedures are validated by measuring the carbon dioxide (CO2) solubility in water and highly viscous bitumen. The experimental results are in good agreement with the available literature data which shows that the technique works well. © 2011 Canadian Society for Chemical Engineering
Development of kerosene–water two‐phase up‐flow in a vertical pipe downstream of A 90° bend
Authors: Hamad F. A. , He S. , Khan M. K. , Bruun H. H. 
Published: December 2011

AbstractThe development of kerosene–water up‐flow in a vertical pipe of 77.8 mm inner diameter and 4500 mm, length downstream of a 90° bend, has been investigated using a Pitot tube and dual optical probe. The CFD ANSYS Fluent 12.0 is used to model the flow and the results are compared with experimental data. The CFD provides detailed information on flow structure which is difficult to obtain in experiments. The experimental measurements of the local parameters demonstrate that the single phase and two‐phase flows reached the fully developed axisymmetrical conditions at L/D = 54. These results also show the severe asymmetry distributions of the two‐phase flow parameters at the entrance region (L/D = 1). The predictions from Fluent are found to be in close agreement with experimental data for L/D ≥ 16 but there is a significant discrepancy at L/D = 1. © 2011 Canadian Society for Chemical Engineering
Development of the scratch resistance on acrylic sheet with basic colloidal silica (SiO2)—methyltrimethoxysilane (MTMS) nanocomposite films by sol–gel technique
Authors: Chantarachindawong Rojcharin , Luangtip Wasutap , Chindaudom Pongpan , Osotchan Tanakorn , Srikhirin Toemsak 
Published: December 2011

AbstractThe formation of scratch‐resistant coating film prepared from colloidal silica and a polysiloxane matrix was investigated. Methyltrimethoxysilane (MTMS) was hydrolysed and mixed with silica sol (SiO2) at various compositions to form the hybrid hard‐coating nanocomposite film. The hydrolysed MTMS (polysiloxane) acts as the polymeric binder that is covalently linked to the colloidal silica surface and provides adhesion for the scratch resistant coating film to the substrate. The ratio between the polymeric matrix and the SiO2 nanoparticles was found to play a major role in controlling the coating film appearance and its resistance to scratching. At a SiO2 content < 30 wt.%, the agglomeration of the hydrolysed polysiloxane was observed and caused the opacity of the coating film. At a SiO2 content >70 wt.%, there was not enough polysiloxane to act as a binder for the SiO2, therefore a shrinkage upon solidification of the coating film caused cracking within the nanocomposite film. The optimum ratio was found to be at 40 wt.% ≤SiO2 ≤60 wt.%, where the films had a transparent, crack free hard coating, with excellent scratch resistance, good adhesion and very good environmental resistance. The nanoindentation revealed that the nanocomposite film, at the optimum loading, possessed a higher strength with a higher SiO2 loading. Film properties, including hardness, scratch resistance, adhesion and environmental resistance were also examined. The morphology of nanocomposite films was identified by atomic force microscopy (AFM) and scanning electron microscopy (SEM). © 2011 Canadian Society for Chemical Engineering
Evaluation of some new hyperbranched polyesters as binding agents for heavy metals
Authors: Asaad J. N. , Ikladious N. E. , Awad F. , Müller T. 
Published: December 2011

AbstractDifferent generations of hydroxyl and carboxyl terminated hyperbranched polyesters were synthesised and used as heavy metals chelating compounds. The adsorptive capacity of the 3rd generation of the polyesters (G3‐OH, G3‐COOH) as well as that of nanoclay (Nanofil 116) for cadmium removal was determined through adsorption isotherm studies. The highest metal ion removal capacity was observed for G3‐COOH sample. The extent of binding (EOB) values of various generations of hyperbranched polyesters having the same core structure, but different terminal groups, indicated that, irrespective of the type of terminal group, the higher generations are more effective than the lower ones. EOB data can be adequately described by a bidentate coordination model for carboxyl terminated polyesters [each Cd(II) ion coordinates with two carboxyl groups] and tetradentate coordination model for hydroxyl terminated polyesters [1Cd(II)/4OH]. The EOB and selectivity properties of all prepared polyesters towards the heavy metal ions Cd(II), Cu(II), and Pb(II), were investigated under competitive condition. The results showed that the carboxyl terminated polymers exhibit higher binding capacities than those of hydroxyl terminated ones and the selectivity follows the order: Cu(II) > Cd(II) > Pb(II) for all polymer samples, irrespective of the type of terminal group. © 2011 Canadian Society for Chemical Engineering