bluuebunny/crossref_metadata_2025_split huggingface dataset:
In Situ Forming Physical Hydrogels for Three‐dimensional Tissue Morphogenesis
Authors: Liu Yang , Liu Bo , Riesberg Jeremiah J. , Shen Wei 
Published: July 2011

AbstractIn situ forming physical hydrogels are formed through a biologically benign reaction between two multi‐arm macromers, one containing terminal thiol and the other containing terminal vinyl sulfone groups. One macromer is self‐assembled through a coiled‐coil domain; and the physical junction of this macromer confers the physical nature to the whole network. Unlike covalently cross‐linked hydrogels in which material degradation is a prerequisite for three‐dimensional cell movement, these physical hydrogels have junctions that undergo reversible dissociation and re‐association, constitutively opening paths for cell movement. Epithelial cells encapsulated in these hydrogels can form hollow spherical cysts without the need for material degradation.magnified image
In Situ Photopolymerization of Biomaterials by Thiol‐yne Click Chemistry
Authors: Lomba Miguel , Oriol Luis , Alcalá Rafael , Sánchez Carlos , Moros María , Grazú Valeria , Serrano José Luis , De la Fuente Jesús M. 
Published: July 2011

AbstractThe thiol‐yne click chemistry reaction has been used for the in situ photocrosslinking of an aliphatic hyperbranched polyester. The biocompatibility of the resulting networks has been studied and marked cytotoxicity was not found for HeLa (human cervical carcinoma) tumoral cells and COS7 fibroblasts. The photoinduced thiol‐yne process allows the generation of patterned structures with different geometries in films by DLW and these materials can be used as substrates for cell adhesion. The influence of the substrate geometry on cell adhesion has been studied by culturing cells onto these substrates and a preference for the photopatterned polymeric material can be seen in some of the structures by contrast phase microscopy. Actin and vinculin fluorescent staining revealed different adhesion behavior for HeLa cells and COS7 fibroblasts and this could be assigned to the different motility of cells. The thiol‐yne photoreaction has proven to be an attractive approach for the preparation of micropatterned biomaterials.magnified image
Polysulfone/Clay Nanocomposites by in situ Photoinduced Crosslinking Polymerization
Authors: Dizman Cemil , Ates Sahin , Uyar Tamer , Tasdelen Mehmet Atilla , Torun Lokman , Yagci Yusuf 
Published: July 2011

AbstractPSU/MMT nanocomposites are prepared by dispersing MMT nanolayers in a PSU matrix via in situ photoinduced crosslinking polymerization. Intercalated methacrylate‐functionalized MMT and polysulfone dimethacrylate macromonomer are synthesized independently by esterification. In situ photoinduced crosslinking of the intercalated monomer and the PSU macromonomer in the silicate layers leads to nanocomposites that are formed by individually dispersing inorganic silica nanolayers in the polymer matrix. The morphology of the nanocomposites is investigated by XRD and TEM, which suggests the random dispersion of silicate layers in the PSU matrix. TGA results confirm that the thermal stability and char yield of PSU/MMT nanocomposites increases with the increase of clay loading.magnified image
Synthesis of Well‐defined Amphiphilic Block Copolymers by Organotellurium‐Mediated Living Radical Polymerization (TERP)
Authors: Kumar Santosh , Changez Mohammad , Murthy C. N. , Yamago Shigeru , Lee Jae‐Suk 
Published: July 2011

AbstractLow‐molecular weight amphiphilic diblock copolymers, polystyrene‐block‐poly (2‐vinylpyridine) (PS‐b‐P2VP), and (P2VP‐b‐PS) with different block ratios were synthesized for the first time via organotellurium‐mediated living radical polymerization (TERP). For both the homo‐ and block copolymerizations, good agreement between the theoretical, and experimental molecular weights was found with nearly 100% yield in every case. The molecular weight distribution for all the samples ranged between 1.10 and 1.24, which is well below the theoretical lower limit of 1.50 for a conventional free radical polymerization. Furthermore, a very simple approach to producing highly dense arrays of titania nanoparticles (TiO2) is presented using a site‐selective reaction of titanium tetraisopropoxide within the P2VP domains of micellar film of P2VP‐b‐PS in toluene through the sol–gel method.magnified image
Functional Microgels Tailored by Droplet‐Based Microfluidics
Authors: Seiffert Sebastian 
Published: July 2011

AbstractMonodisperse polymer gel particles with micrometer‐scale dimensions serve for a variety of applications, including those as microcapsules for actives or as micrometer‐sized matrixes for mesoscopic additives. These particles can be produced with exquisite control through the use of droplet‐based microfluidic templating followed by subsequent droplet solidification. This can be achieved by two ways: One way is to use pre‐microgel solutions of low molecular weight monomers and to form microgels by polymerizing these monomers. Another way is to use pre‐polymerized, high molecular weight precursors and to gel them by polymer‐analogous crosslinking. Both approaches have their specific advantages, allowing microgels to be tailored and optimized for specific needs such as those as delivery systems or scaffolds for living cells. This article highlights some recent achievements in the development and use of these microfluidic techniques to fabricate functional microgel particles.magnified image
The C‐terminus of Apc does not influence intestinal adenoma development or progression
Authors: Lewis Annabelle , Davis Hayley , Deheragoda Maesha , Pollard Patrick , Nye Emma , Jeffery Rosemary , Segditsas Stefania , East Philip , Poulsom Richard , Stamp Gordon , Wright Nicholas , Tomlinson Ian 
Published: July 2011

AbstractAdenomatous polyposis coli (APC) mutations are found in most colorectal tumours. These mutations are almost always protein‐truncating, deleting both central domains that regulate Wnt signalling and C‐terminal domains that interact with the cytoskeleton. The importance of Wnt dysregulation for colorectal tumourigenesis is well characterized. It is, however, unclear whether loss of C‐terminal functions contributes to tumourigenesis, although this protein region has been implicated in cellular processes—including polarity, migration, mitosis, and chromosomal instability (CIN)—that have been postulated as critical for the development and progression of intestinal tumours. Since almost all APC mutations in human patients disrupt both central and C‐terminal regions, we created a mouse model to test the role of the C‐terminus of APC in intestinal tumourigenesis. This mouse (Apc$^{{\Delta}{\rm{SAMP}}}$) carries an internal deletion within Apc that dysregulates Wnt by removing the beta‐catenin‐binding and SAMP repeats, but leaves the C‐terminus intact. We compared Apc$^{{\Delta}{\rm{SAMP}}}$ mice with Apc$^{\rm{1322T}}$ animals. The latter allele represented the most commonly found human APC mutation and was identical to Apc$^{{\Delta}{\rm{SAMP}}}$ except for absence of the entire C‐terminus. Apc$^{{\Delta}{\rm{SAMP}}}$ mice developed numerous intestinal adenomas indistinguishable in number, location, and dysplasia from those seen in Apc$^{\rm{1322T}}$ mice. No carcinomas were found in Apc$^{{\Delta}{\rm{SAMP}}}$ or Apc$^{\rm{1322T}}$ animals. While similar disruption of the Wnt signalling pathway was observed in tumours from both mice, no evidence of differential C‐terminus functions (such as cell migration, CIN, or localization of APC and EB1) was seen. We conclude that the C‐terminus of APC does not influence intestinal adenoma development or progression. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Overexpression of the Flii gene increases dermal–epidermal blistering in an autoimmune ColVII mouse model of epidermolysis bullosa acquisita
Authors: Kopecki Zlatko , Arkell Ruth M , Strudwick Xanthe L , Hirose Misa , Ludwig Ralf J , Kern Johannes S , Bruckner‐Tuderman Leena , Zillikens Detlef , Murrell Dedee F , Cowin Allison J 
Published: July 2011

AbstractEpidermolysis bullosa (EB) is a severe genetic skin fragility syndrome characterized by blister formation. The molecular basis of EB is still largely unknown and wound healing in patients suffering from EB remains a major challenge to their survival. Our previous studies have identified the actin remodelling protein Flightless I (Flii) as an important mediator of wound repair. Here we identify Flii as a novel target involved in skin blistering. Flii expression was significantly elevated in 30 patients with EB, most prominently in patients with recessive dystrophic EB (RDEB) who have defects in production of type VII collagen (ColVII). Using an autoimmune ColVII murine model of EB acquisita (EBA) and an immunocompetent‐ColVII‐hypomorphic genetic mouse model of RDEB together with murine Flii alleles, we investigated the contribution of Flii to EB. Overexpression of Flii produced severe blistering post‐induction of EBA, while decreased Flii reduced blister severity, elevated integrin expression, and improved ColVII production. Flii+/− blistered skin showed reduced α‐SMA, TGF‐β1, and Smad 2/3 expression, suggesting that decreasing Flii may affect fibrosis. In support of this, Flii‐deficient fibroblasts from EBA mice were less able to contract collagen gels in vitro; however, addition of TGF‐β1 restored collagen contraction, suggesting an interplay between Flii and TGF‐β1. Elevated Flii gene and protein expression was further observed in the blisters of ColVII hypomorphic mice, a murine model of RDEB, suggesting that reducing Flii in blistered skin could be a potential new approach for treating patients with EB. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
NADPH oxidase inhibition ameliorates Trypanosoma cruzi‐induced myocarditis during Chagas disease
Authors: Dhiman Monisha , Garg Nisha Jain 
Published: July 2011

AbstractTrypanosoma cruzi, the aetiological agent of Chagas disease, invades nucleated mammalian cells including macrophages. In this study, we investigated the crosstalk between T. cruzi‐induced immune activation of reactive oxygen species (ROS) and pro‐inflammatory responses, and their role in myocardial pathology. Splenocytes of infected mice (C3H/HeN) responded to Tc‐antigenic stimulus by more than a two‐fold increase in NADPH oxidase (NOX) activity, ROS generation, cytokine production (IFN‐γ > IL‐4 > TNFα > IL1‐β≈ IL6), and predominant expansion of CD4+ and CD8+ T cells. Inhibition of NOX, but not of myeloperoxidase and xanthine oxidase, controlled the ROS (>98%) and cytokine (70–89%) release by Tc‐stimulated splenocytes of infected mice. Treatment of infected mice with apocynin (NOX inhibitor) in drinking water resulted in a 50–90% decline in endogenous NOX/ROS and cytokine levels, and splenic phagocytes' proliferation. The splenic percentage of T cells was maintained, though more than a 40% decline in splenic index (spleen weight/body weight) indicated decreased T‐cell proliferation in apocynin‐treated/infected mice. The blood and tissue parasite burden were significantly increased in apocynin‐treated/infected mice, yet acute myocarditis, ie inflammatory infiltrate consisting of macrophages, neutrophils, and CD8+ T cells, and tissue oxidative adducts (eg 8‐isoprostanes, 3‐nitrotyrosine, and 4‐hydroxynonenal) were diminished in apocynin‐treated/infected mice. Consequently, hypertrophy (increased cardiomyocytes' size and β‐MHC, BNP, and ANP mRNA levels) and fibrosis (increased collagen, glycosaminoglycans, and lipid contents) of the heart during the chronic phase were controlled in apocynin‐treated mice. We conclude that NOX/ROS is a critical regulator of the splenic response (phagocytes, T cells, and cytokines) to T. cruzi infection, and bystander effects of heart‐infiltrating phagocytes and CD8+ T cells resulting in cardiac remodelling in chagasic mice. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Evaluation of polymorphisms in EWSR1 and risk of Ewing sarcoma: A report from the childhood cancer survivor study
Authors: DuBois Steven G. , Goldsby Robert , Segal Mark , Woo Jonathan , Copren Kirsten , Kane John P. , Pullinger Clive R. , Matthay Katherine K. , Witte John , Lessnick Stephen L. , Robison Leslie L. , Bhatia Smita , Strong Louise C. 
Published: July 2011

AbstractBackgroundEwing sarcoma is a malignant bone tumor characterized by a high frequency of somatic EWSR1 translocations. Ewing sarcoma is less common in people of African or African‐American ancestry, suggesting a genetic etiology.ProcedureGermline DNA from white patients with Ewing sarcoma (n = 135), white controls with Wilms tumor (n = 200), and African‐American controls (n = 285) was genotyped at 21 SNPs in the EWSR1 gene. Intron 7 of EWSR1, the most common site of translocation, was also sequenced in all subjects. Genetic variation between groups was evaluated statistically using exact logistic regression and Fisher exact tests.ResultsOne SNP in EWSR1 (rs2857461) showed a low level of statistical association with the diagnosis of Ewing sarcoma compared to Wilms tumor. The odds ratio for having Ewing sarcoma in people with at least one copy of the minor allele of rs2857461 was 3.57 (95% confidence interval 0.79–21.7; P = 0.07). No other SNPs or variations in intron 7 of EWSR1 were associated with Ewing sarcoma. The median relative difference in minor allele frequencies between white subjects with Ewing sarcoma and African‐American controls at the evaluated EWSR1 SNPs was 45%.ConclusionsVariations in EWSR1 at known SNPs or across intron 7 are not associated with the diagnosis of Ewing sarcoma. EWSR1 does not appear to be an Ewing sarcoma susceptibility gene. The genetic basis for this disease remains unknown. Pediatr Blood Cancer 2012; 59: 52–56. © 2011 Wiley Periodicals, Inc.
Synergistic effects of titanium dioxide with layered double hydroxides in EVA/LDH composites
Authors: Jiao Chuanmei , Chen Xilei 
Published: July 2011

AbstractThe synergistic effects of titanium dioxide (TiO2) with layered double hydroxides (LDH) in ethylene vinyl acetate copolymer/LDH (EVA/LDH) composites have been studied using thermogravimetric analysis (TGA), limiting oxygen index (LOI), UL‐94 tests, and cone calorimeter test (CCT). The results from the UL‐94 test show that the TiO2 can also act as flame retardant synergistic agents in the EVA/LDH composites. The CCT data indicated that the addition of TiO2 in EVA/LDH system can greatly reduce the heat release rate and the production rate of carbon monoxide. The TGA data show that the TiO2 as excellent flameretardant synergist of LDH can increase the thermal stability of the flame retardant composites at high temperature, indicating the effect of condensed phase mechanism is the main reason of the improvement of flame retardancy. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Feasibility study of thin microinjection molded components
Authors: Mahmoodi Mehdi , Park Simon S. , Rizvi Ghaus 
Published: July 2011

AbstractThe trend toward the miniaturization of parts has created a strong demand for the manufacturing of precision‐molded miniature polymeric components, due to their high productivity and cost‐effectiveness. The objective of this study is the investigation of the filling behavior and dimensional accuracy of thin microinjection‐molded components using chemical blowing agents and wood fibers. In order to investigate the dimensional stability of the miniature molded parts, a micromold was designed and manufactured using a precision micromilling machine. The flow pattern of the thin molded components was experimentally investigated using different materials: pure linear low‐density polyethylene (LLDPE), foamed LLDPE, and wood fiber LLDPE composite. The results indicate that viscosity significantly affects the flow patterns. Filling behavior of the molded parts was also investigated using commercial flow software. Dimensional accuracy and shrinkage of the molded parts were measured using various gauges. Controlling the cell size, cell density, and distribution of foamed parts was especially difficult for thin micro components; however, the results showed that use of chemical blowing agents can improve the flow ability of the thin components in the microinjection molding process. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Gender differences and social support: Mediators or moderators between peer victimization and depressive feelings?
Authors: Pouwelse Mieneke , Bolman Catherine , Lodewijkx Hein , Spaa Marguerite 
Published: July 2011

AbstractUsing self‐report questionnaires, a survey among 606 Dutch primary school children aged 10 to 12 years examined relationships among social support, gender, victimization, and depressive feelings. Hierarchical regression analyses confirmed that victims and bully/victims would report more depressive feelings than uninvolved children. There was no evidence that social support moderated the relationship between victimization and depressive feelings. However, social support appeared to influence the depressive feelings of victimized children, that is, pupils who were victimized received very little support and hence suffered depression. This general mediation effect could be observed in boys. In girls, the mediating effects of social support were more diffuse. For girls, the risk factor for the development of depressive feelings did not so much pertain to the type of bullying as to the subsequent lack of social support they experienced. © 2011 Wiley Periodicals, Inc.
Prediction of biological protein–protein interactions using atom‐type and amino acid properties
Authors: Aziz Md. Mominul , Maleki Mina , Rueda Luis , Raza Mohammad , Banerjee Sridip 
Published: July 2011

AbstractIdentification and analysis of types of biological protein–protein interactions and their interfaces to predict obligate and non‐obligate complexes is a problem that has drawn the attention of the research community in the past few years. In this paper, we propose a prediction approach to predict these two types of complexes. We use desolvation energies – amino acid and atom type – of the residues present in the interface. The prediction is performed via two state‐of‐the‐art classification techniques, namely linear dimensionality reduction (LDR) and support vector machines (SVM). The results on a newly compiled data set, namely BPPI, which is a joint and modified version of two well‐known data sets consisting of 213 obligate and 303 non‐obligate complexes, show that the best prediction is achieved with SVM (76.94% accuracy) when using desolvation energies of atom‐type features. Also, the proposed approach outperforms the previous solvent accessible area‐based approaches using SVM (75% accuracy) and LDR (73.06% accuracy). Moreover, a visual analysis of desolvation energies in obligate and non‐obligate complexes shows that a few atom‐type pairs are good descriptors for these types of complexes.
Automated protein structure modeling in CASP9 by I‐TASSER pipeline combined with QUARK‐based ab initio folding and FG‐MD‐based structure refinement
Authors: Xu Dong , Zhang Jian , Roy Ambrish , Zhang Yang 
Published: July 2011

AbstractI‐TASSER is an automated pipeline for protein tertiary structure prediction using multiple threading alignments and iterative structure assembly simulations. In CASP9 experiments, two new algorithms, QUARK and fragment‐guided molecular dynamics (FG‐MD), were added to the I‐TASSER pipeline for improving the structural modeling accuracy. QUARK is a de novo structure prediction algorithm used for structure modeling of proteins that lack detectable template structures. For distantly homologous targets, QUARK models are found useful as a reference structure for selecting good threading alignments and guiding the I‐TASSER structure assembly simulations. FG‐MD is an atomic‐level structural refinement program that uses structural fragments collected from the PDB structures to guide molecular dynamics simulation and improve the local structure of predicted model, including hydrogen‐bonding networks, torsion angles, and steric clashes. Despite considerable progress in both the template‐based and template‐free structure modeling, significant improvements on protein target classification, domain parsing, model selection, and ab initio folding of β‐proteins are still needed to further improve the I‐TASSER pipeline. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Motivation, achievement, and advanced placement intent of high school students learning science
Authors: Bryan Robert R. , Glynn Shawn M. , Kittleson Julie M. 
Published: July 2011

AbstractWithin the framework of social cognitive theory, we examined the motivation of students (14–16 years old) to learn science in their introductory science courses. The students responded to a questionnaire about their intrinsic motivation, self‐efficacy, and self‐determination. The students also wrote essays about their motivation, and individual interviews were conducted with a representative sample of students. We found that the students' intrinsic motivation, self‐efficacy, self‐determination, and achievement were related. Consistent with social cognitive theory, self‐efficacy was the motivation factor most related to achievement. The Advanced Placement Program (AP) aspirants were higher than nonaspirants in intrinsic motivation, self‐efficacy, self‐determination, and achievement. Patterns in students' essays and interviews identified inspiring teachers, career interests, and collaborative‐learning activities as strong motivators. The findings suggest that science teachers should use social modeling and collaborative‐learning activities to foster students' motivation, achievement, AP intent, and interest in science careers. © 2011 Wiley Periodicals, Inc. Sci Ed 95:1049–1065, 2011
Accuracy of imaging parameters in the prediction of lethal pulmonary hypoplasia secondary to mid‐trimester prelabor rupture of fetal membranes: a systematic review and meta‐analysis
Authors: van Teeffelen A. S. P. , Van Der Heijden J. , Oei S. G. , Porath M. M. , Willekes C. , Opmeer B. , Mol B. W. J. 
Published: July 2011

AbstractIn women who have suffered mid‐trimester prelabor rupture of membranes (PPROM), prediction of pulmonary hypoplasia is important for optimal management. We performed a systematic review to assess the capacity of imaging parameters to predict pulmonary hypoplasia. We searched for published articles that reported on biometric parameters and allowed the construction of a 2 × 2 table, comparing at least one of these parameters with the occurrence of pulmonary hypoplasia. The selected studies were scored on methodological quality and we calculated sensitivity and specificity of the tests in the prediction of pulmonary hypoplasia and lethal pulmonary hypoplasia. Overall performance was assessed by summary receiver–operating characteristics (sROC) analyses that were performed with bivariate meta‐analysis. We detected 13 studies that reported on the prediction of lethal pulmonary hypoplasia. The quality of the included studies was poor to mediocre. The estimated sROC curves for the chest circumference/abdominal circumference ratio and other parameters showed limited accuracy in the prediction of pulmonary hypoplasia. In women with mid‐trimester PPROM, the available evidence indicates limited accuracy of biometric parameters in the prediction of pulmonary hypoplasia. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.