bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of New SRF Binding Sites in Genes Modulated by SRF Over-Expression in Mouse Hearts
Authors: Zhang Xiaomin , Azhar Gohar , Helms Scott , Burton Brian , Huang Chris , Zhong Ying , Gu Xuesong , Fang Hong , Tong Weida , Wei Jeanne Y. 
Published: July 2011

Background To identify in vivo new cardiac binding sites of serum response factor (SRF) in genes and to study the response of these genes to mild over-expression of SRF, we employed a cardiac-specific, transgenic mouse model, with mild over-expression of SRF (Mild-O SRF Tg). Methodology Microarray experiments were performed on hearts of Mild-O-SRF Tg at 6 months of age. We identified 207 genes that are important for cardiac function that were differentially expressed in vivo. Among them the promoter region of 192 genes had SRF binding motifs, the classic CArG or CArG-like (CArG-L) elements. Fifty-one of the 56 genes with classic SRF binding sites had not been previously reported. These SRF-modulated genes were grouped into 12 categories based on their function. It was observed that genes associated with cardiac energy metabolism shifted toward that of carbohydrate metabolism and away from that of fatty acid metabolism. The expression of genes that are involved in transcription and ion regulation were decreased, but expression of cytoskeletal genes was significantly increased. Using public databases of mouse models of hemodynamic stress (GEO database), we also found that similar altered expression of the SRF-modulated genes occurred in these hearts with cardiac ischemia or aortic constriction as well. Conclusion and significance SRF-modulated genes are actively regulated under various physiological and pathological conditions. We have discovered that a large number of cardiac genes have classic SRF binding sites and were significantly modulated in the Mild-O-SRF Tg mouse hearts. Hence, the mild elevation of SRF protein in the heart that is observed during typical adult aging may have a major impact on many SRF-modulated genes, thereby affecting Cardiac structure and performance. The results from our study could help to enhance our understanding of SRF regulation of cellular processes in the aged heart.
Multifunctional Poly(ethylene glycol)s
Authors: Obermeier Boris , Wurm Frederik , Mangold Christine , Frey Holger 
Published: July 2011

AbstractIn the rapidly evolving multidisciplinary field of polymer therapeutics, tailored polymer structures represent the key constituent to explore and harvest the potential of bioactive macromolecular hybrid structures. In light of the recent developments for anticancer drug conjugates, multifunctional polymers are becoming ever more relevant as drug carriers. However, the potentially best suited polymer, poly(ethylene glycol) (PEG), is unfavorable owing to its limited functionality. Therefore, multifunctional linear copolymers (mf‐PEGs) based on ethylene oxide (EO) and appropriate epoxide comonomers are attracting increased attention. Precisely engineered via living anionic polymerization and defined with state‐of‐the‐art characterization techniques—for example real‐time 1H NMR spectroscopy monitoring of the EO polymerization kinetics—this emerging class of polymers embodies a powerful platform for bio‐ and drug conjugation.
Preparation and characterization of an epoxy resin modified by a combination of MDI‐based polyurethane and montmorillonite
Authors: Kostrzewa Marcin , Hausnerova Berenika , Bakar Mohamed , Pająk Karolina 
Published: July 2011

AbstractThe present work investigates the modification of epoxy resin by using a combination of nanoclay (montmorillonite—Cloisite 30B) and a liquid polymeric modifier (polyurethane). Polyurethane was obtained from 4,4′‐diphenylmethane diisocyanate and polydiols with different molecular weight: polyethylene glycol (PEG 400) and polyoxypropylene diols with molecular weight 1000 g/mol and 2000 g/mol. The impact strength, the critical stress intensity factor as well as the flexural strength were evaluated as functions of modifiers content. The obtained results showed that hybrid composites exhibit enhanced mechanical properties without significant changes of the glass transition temperature. FTIR analysis showed that chemical reactions took place between the hydroxyl groups of epoxy resin and the isocyanate groups of polyurethane, explaining an improvement of the mechanical properties of epoxy resin. However, XRD results demonstrated the formation of an exfoliated structure for the hybrid compositions with both polyurethane and montmorillonite. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
PET/PA nanocomposite blends with improved gas barrier properties: Effect of processing conditions
Authors: Donadi S. , Modesti M. , Lorenzetti A. , Besco S. 
Published: July 2011

AbstractThe aim of this research is to develop nanocomposite polyethylene terephthalate‐polyamide blends (PET/MXD6 blends) with low oxygen permeability. Particular attention has been paid to the relation between barrier properties and the processing route adopted and therefore four different strategies were considered. Mechanical characterization shows that clay may effectively act as reinforcing filler in PET/MXD6 blends. Morphological characterization shows the strong effect of the processing strategy on clay dispersion and its distribution between the PET and polyamide phases. Barrier properties of PET/MXD6 nanocomposite blends are enhanced with respect to neat PET polymer as well as PET/MXD6 blends. The significant effect of processing techniques on barrier properties is also revealed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Effect of different metallic hydroxides on flame‐retardant properties of low density polyethylene/melamine polyphosphate/starch composites
Authors: Gao Huliang , Hu Shan , Han Hongchang , Zhang Jun 
Published: July 2011

AbstractThe flame retardancy of synthesized melamine polyphosphate (MPP) in combination with starch (ST) and different metallic hydroxides was investigated in low density polyethylene (LDPE) by limiting oxygen index (LOI) and vertical burning test. The results indicated that the LOI value of composite comprising Al(OH)3(ATH) was higher than those of composites at the same additive loading with Mg(OH)2(MH)or Fe(OH)3(FH), which increased from 22 to 27%. And the composite comprising ATH passed V1 rating without causing molten drops. In addition, thermostability and morphology were characterized by differential scanning calorimeter (DSC), thermogravimetry (TG), derivative thermogravimetry (DTG), and scanning electron microscope (SEM). The results demonstrated that the crystallization of the composites remained unaffected after the incorporation of metallic hydroxide. The thermal degradation behavior of LDPE composites and the morphology of residual charred layer were changed. It also can be concluded that there was a synergy between certain metallic hydroxide and MPP after analyzing the residual charred layer using X‐ray diffraction (XRD). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
ARGET ATRP of acrylonitrile with ionic liquid as reaction medium and FeBr3/isophthalic acid as catalyst system
Authors: Chen Hou , Wang Chunhua , Liu Delong , Wang Min , Ji Chunnuan 
Published: July 2011

AbstractAtom transfer radical polymerization using activators regenerated by electron transfer (ARGET ATRP) of acrylonitrile with FeBr3 and isophthalic acid (IA) as catalyst and ligand, ascorbic acid (VC) as reducing agent, and ethyl 2‐bromoisobutyrate as initiator was approached for the first time in the presence of air in 1‐dodecyl‐3‐methylimidazolium tetrafluoroborate ([C12mim][BF4]), 1‐octyl‐3‐methylimidazolium tetrafluoroborate ([C8mim][BF4]), and 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([C4mim][BF4]). The rate of polymerization in [C12mim][BF4] was considerably faster than in [C8mim][BF4] and [C4mim][BF4]. With an increase of VC concentration, both the monomer conversion and the molecular weight distribution showed a trend of increase. Polyacrylonitrile (PAN) with higher molecular weight at 166,250 and broader distribution at 1.34 was successfully prepared with PAN as macroinitiator via ARGET ATRP in [C12mim][BF4] in the presence of air. The resultant polyacrylonitrile fibers were obtained with the fineness at 1.15 dtex and the tenacity at 6.24 cN dtex−1. Additionally, it was shown that [C12mim][BF4] could be recycled and reused after simple purification and had no effect on the living nature of polymerization. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Nano and submicrometric fibers of poly(D,L‐lactide) obtained by solution blow spinning: Process and solution variables
Authors: Oliveira Juliano E. , Moraes Eduardo A. , Costa Rodrigo G. F. , Afonso André S. , Mattoso Luiz H. C. , Orts William J. , Medeiros Eliton S. 
Published: July 2011

AbstractNano and submicrometric fibers of poly(D,L‐lactide) (PDLLA or PLA) were spun from solutions using a solution blow spinning (SBS) apparatus. Fiber morphology and diameter were investigated by scanning electron microscopy as a function of polymer concentration, feed rate, and air pressure. A more systematic understanding of the SBS process parameters was obtained, and a quantitative relationship between these parameters and average fiber diameter was established by design of experiments and response surface methodology. It was observed that polymer concentration played an important role in fiber diameter, which ranges from 70 to 2000 nm, and its distribution. Lower polymer concentration tended to increase the formation of bead‐on‐string structures, whereas smooth fibers were formed at higher concentrations. Fiber diameter tended to increase with polymer concentration and decrease with feed rate. Based on these results, optimal conditions could be obtained for solution‐blow spun fibers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Synthesis and photochromic properties of naphthopyran polymer containing photocrosslinkable coumarin moiety
Authors: Xie Bingjie , Wang Guang , Zhao Xiancai 
Published: July 2011

AbstractNaphthopyran homopolymer and copolymer containing coumarin in side chain were synthesized by atom transfer radical polymerization. Their photochromic properties were investigated using UV–vis absorption spectroscopy and their decoloration kinetics in films was quantified by biexponential fitting of their photochromic decoloration curves after UV irradiation. The results showed that the photochromism and photocrosslinking occurred simultaneously under UV irradiation, and the photocrosslinking of coumarin reduced the decoloration rate of naphthopyran. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
The influence of annealing treatment on the molecular structure and the mechanical properties of isotactic polypropylene fibers
Authors: Karacan Ismail , Benli Hüseyin 
Published: July 2011

AbstractAn investigation was carried out on the effects of annealing treatment on the molecular structure and the mechanical properties of isotactic polypropylene fibers annealed in an air heated environment at temperatures ranging from 60 to 140°C. Analysis of the equatorial X‐ray diffraction traces showed the presence of a three phase system of amorphous‐smectic‐monoclinic forms and revealed the transformation of the metastable smectic form to the highly stable monoclinic form as the annealing temperature is increased, resulting in an enhanced degree of crystallinity and the crystallite size. The improvements in the degree of crystallinity and the crystallite size became more remarkable above 120°C. Evaluation of the crystallinity was carried out using an analysis of density, infrared spectroscopy, and X‐ray diffraction methods whereas the state of the molecular orientation was evaluated using polarized infrared spectroscopy measurements only. Polarized infra‐red spectroscopy measurements after the curve fitting procedure showed a slight increase of the molecular orientation of the helical chain segments present in the crystalline phase represented by the IR bands at 841 and 998 cm−1 whereas the amorphous structure represented by the IR band at 974 cm−1 showed no significant change with increasing annealing temperature. The improvement in the molecular orientation of the crystalline phase became more remarkable above 120°C. Tensile strength of the annealed fibers increased with increasing annealing temperature but the elongation at break and the initial modulus were not affected as much as the tensile strength. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Highly Active Copper‐Network Catalyst for the Direct Aldol Reaction
Authors: Ohta Hidetoshi , Uozumi Yasuhiro , Yamada Yoichi M. A. 
Published: July 2011

AbstractThe development of a highly active solid‐phase catechol–copper network catalyst for direct aldol reaction is described. The catalyst was prepared from an alkyl‐chain‐linked bis(catechol) and a copper(II) complex. The direct aldol reaction between carbonyl compounds (aldehydes and ketones) and methyl isocyanoacetate was carried out using 0.1–1 mol % [Cu] catalyst to give the corresponding oxazolines at yields of up to 99 % and a trans/cis ratio of >99:1. The catalyst was reused with no loss of catalytic activity. A plausible reaction pathway is also described.
Click Chemistry‐Based Functionalization on Non‐Oxidized Silicon Substrates
Authors: Li Yan , Cai Chengzhi 
Published: July 2011

AbstractCopper‐catalyzed azide–alkyne cycloaddition (CuAAC), combined with the chemical stability of the SiC‐bound organic layer, serves as an efficient tool for the modification of silicon substrates, particularly for the immobilization of complex biomolecules. This review covers recent advances in the preparation of alkynyl‐ or azido‐terminated “clickable” platforms on non‐oxidized silicon and their further derivatization by means of the CuAAC reaction. The exploitation of these “click”‐functionalized organic thin films as model surfaces to study many biological events was also addressed, as they are directly relevant to the on‐going effort of creating silicon‐based molecular electronics and chemical/biomolecular sensors.
Nonthermal emission from the radio relic of the galaxy cluster A2256
Authors: Siemieniec‐Ozieblo G. , Pasternak B.M. 
Published: July 2011

AbstractWe aim to obtain a consistent description of non‐thermal emissions from Abell 2256 and to give a prediction for a gamma‐ray emission from this galaxy cluster. Assuming that a radio relic illuminates a localization of an ongoing merger, and that both radio and non‐thermal part of hard X‐ray emission are due to electron component of cosmic rays filling the relic, we derived from radio and hard X‐ray properties of the relic in A2256 the magnetic field strength and number densities for relativistic electrons and protons. Due to the interpretation of the radio relic as a structure formed just where a shock front is, we discuss a gamma‐ray emission at the cluster periphery. The estimated strength of the magnetic field in the relic is equal to 0.05 µG, while the amplitude of the electron number density varies from 3×10–4 to 3×10–5 cm–3 (respectively for the relic thickness of 50 to 500 kpc). We got a substantial degree of non‐equipartition between cosmic rays and magnetic field in the relic region, where the CR pressure is approaching that of thermal gas. Our prediction for LOFAR is a synchrotron flux from the relic region of the order of ∼6 Jy at 60MHz and ∼10 Jy at 30MHz. The lower limit of the γ ‐ray flux from the relic region calculated for a hadronic channel is of the order of 10–12 erg cm–2 (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Creation, detection, and evolution of Jupiter Trojan families
Authors: Karlsson O. 
Published: July 2011

AbstractAn investigation is carried out looking at correlations between the orbital elements of collisional targets and projectiles, estimating the number of interlopers in Trojan collisional families, and at the possibility of determining the ages of the Jupiter Trojan families by orbital integration. Real Trojans are integrated and close encounters are recorded in order to evaluate collisional circumstances between Trojans. Fictitious collisional families are created and integrated for 10 MJyr (million Julian years) forward in time and back again to the time of the collision in order to check the performance of the integrator, and the behaviour of the fictitious collisional fragments. Proper elements are calculated for the detection of family clustering using the hierarchically clustering method. This method presents little difficulty finding fictitious families in the Trojan swarms even in areas with densely populated backgrounds. However, even when the background is relatively sparse in objects, several interlopers can be connected to the family at velocity differences below 100 m s–1. On the other hand, in densely populated backgrounds the contamination of interlopers should be less than 30%. Providing gravity is the only significant force acting on the Trojans and resonance effects are weak, the shape the collision fragments create in the proper element space are preserved on the GJyr scale, and collisions can be tracked with orbital integrations for ages of at least 100 MJyr. However, the shape of artificial families does not correspond to suggested real families. This points to the need of including non‐gravitational forces such as the Yarkovsky effect in order to simulate the family evolution. As a consequence age determination by orbital integration might be severely restricted and previous investigations involving long term orbital integrations might have tobe recalculated (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effective Separation of Gas and Fluid Phases by Means of Selective Adsorption
Authors: Rosenfeld Henning , Peper Stefanie , Täffner Tim , Kötke Matthias , Fonka Moundih A. , Temme Heike , Niemeyer Bernd 
Published: July 2011

AbstractDie Adsorption ist ein leistungsfähiges Verfahren zur Abtrennung von niedrig konzentrierten Stoffen aus komplexen Gemischen. Dabei sind die Affinität und die Selektivität des Adsorbens entscheidend für die Effizienz des Trennverfahrens. Dieser Beitrag gibt einen Überblick über die Mechanismen der Adsorption und zeigt anhand verschiedener Beispiele aus eigenen Forschungsarbeiten in den Bereichen Bioprozess‐, Umwelt‐ und Sicherheitstechnik die Relevanz für technische Anwendungen. Es wird sowohl die Flüssig‐ als auch die Gasphasenadsorption betrachtet und zwischen niedermolekularen Adsorptiven und Biomakromolekülen unterschieden.
A note from history: Landmarks in history of cancer, part 3
Authors: Hajdu Steven I. 
Published: July 2011

AbstractIn the early 19th century, microscopy in pathology replaced gross descriptive pathology of the 18th century. Cells became known as the most important and distinct elements of benign and cancerous tissues. Thus, by the mid‐1800s, a solid foundation had been laid for microscopy, and surgeons recognized that microscopic diagnosis by pathologists merited attention. In due course, preoperative microscopic diagnoses and classification of cancers in biopsy specimens were incorporated into choosing the most fitting surgical operation. Cancer 2012;. © 2011 American Cancer Society.
Xeroderma pigmentosum complementation group C single‐nucleotide polymorphisms in the nucleotide excision repair pathway correlate with prolonged progression‐free survival in advanced ovarian cancer
Authors: Fleming Nicole D. , Agadjanian Hasmik , Nassanian Hoorig , Miller Carl W. , Orsulic Sandra , Karlan Beth Y. , Walsh Christine S. 
Published: July 2011

AbstractBACKGROUND:The nucleotide excision repair (NER) pathway is the principal DNA repair pathway for removing bulky platinum DNA adducts. Suboptimal DNA repair may lead to improved response to platinum agents. The objective of this study was to determine whether single‐nucleotide polymorphisms (SNPs) in NER pathway genes could be markers of platinum response in ovarian cancer.METHODS:The authors identified patients with advanced‐stage, papillary serous ovarian cancer who underwent primary cytoreductive surgery followed by platinum‐based chemotherapy. DNA was isolated from peripheral blood specimens. Twenty‐two SNPs within NER genes (xeroderma pigmentosum [XP] complementation group A [XPA], XPB/excision repair cross‐complementing rodent repair deficiency, complementation group 3 [ERCC3], XPC, XPD/ERCC2, XPF/ERCC4, XPG/ERCC5, Cockayne syndrome group B protein [CSB]/ERCC8, ERCC1) were genotyped using polymerase chain reaction analysis.RESULTS:In total, 139 patients with stage III and IV papillary serous ovarian cancer were genotyped. The XPC (reference SNP 3731108 [rs3731108]) adenosine‐guanine (AG)/AA genotype versus the GG genotype was associated with prolonged a progression‐free survival (PFS) of 21.3 months versus 13.4 months (hazard ratio [HR], 0.63; 95% confidence interval [CI], 0.42‐0.95; P = .03). The XPC (rs1124303) guanosine‐thymidine (GT)/GG genotype versus the TT genotype was associated with a prolonged PFS of 22.8 months versus 14.9 months (HR, 0.47; 95% CI, 0.24‐0.94; P = .03). The XPC poly(AT) (PAT) (−/+)/(−/−) genotype versus the (+/+) genotype was associated with a prolonged PFS of 17 months versus 11.6 months (HR, 0.56; 95% CI, 0.36‐0.89; P = .01). The XPF/ERCC4 (rs12926685) cytidine‐thymidine (CT)/CC genotype versus the TT genotype was associated with a prolonged PFS of 16.7 months versus 12.4 months (HR, 0.63; 95% CI, 0.41‐0.95; P = .03). On multivariate analysis adjusting for breast cancer (BRCA) gene and cytoreductive surgery status, the XPC SNPs remained significantly associated with prolonged PFS.CONCLUSIONS:The current results indicated that XPC is a key component of the NER pathway that participates in DNA damage repair. SNPs in the XPC gene may represent novel markers of ovarian cancer response to platinum‐based chemotherapy. Cancer 2012;. © 2011 American Cancer Society.
Cell surface receptor expression patterns in osteosarcoma
Authors: Hassan Sheref E. , Bekarev Mikhail , Kim Mimi Y. , Lin Juan , Piperdi Sajida , Gorlick Richard , Geller David S. 
Published: July 2011

AbstractBACKGROUND:Although the presence of numerous cell signaling receptors in osteosarcoma is known, their simultaneous characterization has not been performed to date. The current study sought to characterize and quantify the expression of cell surface receptors across a variety of osteosarcoma cell lines.METHODS:Standard (n = 4) and patient‐derived (n = 10) osteosarcoma cell lines were cultured and labeled with antibodies to epidermal growth factor receptor, human epidermal growth factor receptor (HER)‐2, HER‐3, HER‐4, insulin‐like growth factor 1 receptor (IGF‐1R), IGF‐2R, insulin receptor (IR), vascular endothelial growth factor receptor (VEGFR)‐1, VEGFR‐2, VEGFR‐3, c‐Met, fibroblast growth factor receptor (FGFR)‐2, FGFR‐3, and platelet‐derived growth factor receptor (PDGFR)‐β. Cell surface examination was performed using flow cytometry, and the geometric fluorescent mean for each receptor was calculated and compared against a positive control.RESULTS:Significant overexpression of IGF‐2R was shown in all cell lines, with an average geometric mean above the upper expression quartile. A variable expression pattern was seen for c‐Met, PDGFR‐β, IR, IGFR‐1, HER‐2, and VEGFR‐3 with expression values for the remaining receptors mainly in the lower quartile. An apparent association between the expression of IGF‐1R and HER‐2 and between the expression of PDGFR‐β and IR was demonstrated.CONCLUSION:IGF‐2R was consistently overexpressed on the cell surface across all tested osteosarcoma cell lines. Substantial, although variable, expression of c‐Met, HER‐2, IGF‐1R, VEGFR‐3, IR, and PDGFR‐β was demonstrated as well, suggesting that these receptors may contribute to osteosarcoma aggressiveness and biological heterogeneity and may serve as potential targets within a subset of tumors. Associated receptor expression may provide new insight into common regulatory factors or pathways. Targeting either common factors or targeting multiple specific receptors may have therapeutic relevance. Cancer 2012;. © 2011 American Cancer Society.