bluuebunny/crossref_metadata_2025_split huggingface dataset:
Administration of the insulin into the scaffold atelocollagen for tissue‐engineered cartilage
Authors: Ko Edward Chengchuan , Fujihara Yuko , Ogasawara Toru , Asawa Yukiyo , Nishizawa Satoru , Nagata Satoru , Takato Tsuyoshi , Hoshi Kazuto 
Published: March 2011

AbstractThree‐dimensional culture of the tissue‐engineered cartilage constructs may increase the matrix production, but central necrosis must occur if the construct becomes large. To increase the cell viability in the middle part of constructs and to enhance thein vivocartilage regeneration, we attempted to administer the insulin into the scaffold. Insulin is known to strongly enhance the matrix production in the chondrocytes. The pellets of human auricular chondrocytes with atelocollagen hydrogel were 3D‐cultured in the medium. The comparison among three groups (insulin mixed in the atelocollagen, insulin added to the medium, and control group, i.e.; insulin in neither atelocollagen nor medium) revealed that both insulin mixed in the atelocollagen and that in the medium could effectively promoted the cell viability and matrix synthesis of the chondrocytes. The daily assay also showed the gradual release of insulin from the atelocollagen hydrogel, suggesting that this material may work as a control release of insulin. We actually transplanted the poly‐L‐lactide porous scaffolds carrying the chondrocytes and the atelocollagen mixed with or without insulin, into the nude mice, showing that glycosaminoglycan accumulation was evident in the group with insulin although less without insulin. We thus showed the possibility to enhance thein vivocartilage regeneration, when administered insulin into the atelocollagen hydrogel. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 2011.
Osteoblast‐like cell adhesion on porous silicon‐incorporated TiO2 coating prepared by micro‐arc oxidation
Authors: Zhang Zhenxiang , Sun Junying , Hu Hongjie , Wang Quanming , Liu Xuanyong 
Published: March 2011

AbstractSilicon‐incorporated TiO2 coating (Si‐TiO2) was prepared on titanium (Ti) by micro‐arc oxidation (MAO) technique in the Ca, P, Si‐containing electrolyte. The surface topography, phase, and element composition of the coatings were characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD), and energy‐dispersive X‐ray spectrometry (EDS), respectively. Osteoblast‐like MC3T3‐E1 cells were cultured on the surface of the coatings to evaluate their adhesion behavior. The obtained results showed that Si element was successfully incorporated into the porous TiO2 coating, which did not alter apparently the surface topography and phase composition of the coating. The adhesion of the MC3T3‐E1 cells on Si‐incorporated TiO2 coating was significantly enhanced compared with the Si‐free TiO2 coating and pure Ti plates. In addition, the enhanced cell adhesion may at least partly be mediated by integrin β1‐FAK signal transduction pathway. The present work suggests that the Si‐TiO2 coating is worth further consideration for orthopedic implant applications. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Characterization of bionanocomposite scaffolds comprised of amine‐functionalized gold nanoparticles and silicon carbide nanowires crosslinked to an acellular porcine tendon
Authors: Deeken Corey R. , Fox Derek B. , Bachman Sharon L. , Ramshaw Bruce J. , Grant Sheila A. 
Published: March 2011

AbstractAs one of the most common proteins found in the human body, collagen is regarded as biocompatible and has many properties making it ideal for soft‐tissue repair applications. However, collagen matrices fabricated from purified forms of collagen are notoriously weak and easily degraded by the body. The extracellular matrix of many tissues including human dermis, porcine dermis, and porcine small intestine submucosa are often utilized instead, and several of these scaffolds are crosslinked. Crosslinking has been shown to improve the mechanical properties of collagenous tissues and increase their resistance to degradation. In this study we investigated two novel “bionanocomposite” materials in which either gold nanoparticles or silicon carbide nanowires were crosslinked to a porcine tendon. Scanning electron micrographs confirmed that the nanomaterials were successfully crosslinked to the tissues. A collagenase assay, tensile testing, flow cytometry, and bioreactor studies were also performed to further characterize the properties of these novel materials. The results of these studies indicated that crosslinking porcine diaphragm tissues with nanomaterials resulted in scaffolds with improved resistance to enzymatic degradation and appropriate biocompatibility characteristics, thus warranting further study of these materials for soft tissue repair and tissue engineering applications. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Profiling signalling pathways in formalin‐fixed and paraffin‐embedded breast cancer tissues reveals cross‐talk between EGFR, HER2, HER3 and uPAR
Authors: Berg Daniela , Wolff Claudia , Malinowsky Katharina , Tran Kai , Walch Axel , Bronger Holger , Schuster Tibor , Höfler Heinz , Becker Karl‐Friedrich 
Published: March 2011

AbstractIn the last few years, new approaches and developments in patient‐tailored cancer therapies have raised the need to select, more precisely, those patients who will respond to personalized treatments. Therefore, the most efficient way for optimal therapy and patient selection is to provide a tumour‐specific protein network portrait prior to treatment. The aim of our study was to monitor protein networks in formalin‐fixed and paraffin‐embedded (FFPE) breast cancer tissues, with special emphasis on epidermal growth factor receptor 2 (HER2)‐mediated signalling pathways, to identify and validate new disease markers. For this purpose we used a recently developed technology to extract full‐length proteins from FFPE tissues and analysed 23 molecules involved in HER2‐related signalling by reverse phase protein microarray (RPPA) in a series of 106 FFPE breast cancer tissue samples. We found a significant correlation of HER2 with human epidermal growth factor receptor 3 (HER3/erbB3), epidermal growth factor receptor 1 (EGFR/HER1/erbB1) and urokinase plasminogen receptor (uPAR) in routinely used FFPE breast cancer tissues. Thus, targeting HER2, EGFR, HER3 and uPAR together may offer a more efficient treatment option for patients with breast cancer. J. Cell. Physiol. 227: 204–212, 2012. © 2011 Wiley Periodicals, Inc.
Synergistic anti‐tumor activity of isochaihulactone and paclitaxel on human lung cancer cells
Authors: Yu Yung‐Luen , Su Kuo‐Jung , Chen Cheng‐Jueng , Wei Chyou‐Wei , Lin Ching‐Ju , Yiang Giou‐Teng , Lin Shinn‐Zong , Harn Horng‐Jyh , Chen Yi‐Lin Sophia 
Published: March 2011

AbstractDrug resistance frequently develops in tumors during chemotherapy. Therefore, to improve the clinical outcome, more effective and tolerable combination treatment strategies are needed. Here, we show that isochaihulactone (K8) enhanced paclitaxel‐induced apoptotic death in human lung cancer cells, and the enhancing effect was related to increased NSAID‐activated gene‐1 (NAG‐1) expression. CalcuSyn software was used to evaluate the synergistic interaction of K8 and paclitaxel on human lung cancer cells; the synergistic effect of K8 in combination with paclitaxel was increased more than either of these drugs alone. Furthermore, the activity of ERK1/2 was enhanced by the combination of K8 and paclitaxel, and an ERK1/2 inhibitor dramatically inhibited NAG‐1 expression in human lung cancer cells. Therefore, this synergistic apoptotic effect in human lung cancer cells may be directly associated with K8‐induced NAG‐1 expression through ERK1/2 activation. Moreover, over‐expression of NAG‐1 enhanced K8/paclitaxel‐induced apoptosis in human lung cancer cells. In addition, treatment of nude mice with K8 combined with paclitaxel induced phospho‐ERK1/2 and NAG‐1 expression in vivo. Targeting of NAG‐1 signaling could enhance therapeutic efficacy in lung cancer. Our results reveal that activation of NAG‐1 by K8 enhanced the therapeutic efficacy of paclitaxel in human lung cancer cells via the ERK1/2 signaling pathway. J. Cell. Physiol. 227: 213–222, 2012. © 2011 Wiley Periodicals, Inc.
MALDI‐ToF analysis of polythiophene: use of trans‐2‐[3‐(4‐t‐butyl‐phenyl)‐2‐methyl‐ 2‐propenylidene]malononitrile—DCTB—as matrix
Authors: Winter Julien De , Deshayes Gaëlle , Boon Florian , Coulembier Olivier , Dubois Philippe , Gerbaux Pascal 
Published: March 2011

AbstractNowadays, numerous experimental and theoretical studies are devoted to the research field of polythiophenes and other electroconjugated polymers due to the huge potentialities of those conducting polymers. Synthetic procedures are now developed to reach the highest control over both polymerization and analytical methodologies allowing an in‐depth and straightforward characterization of the polymer samples without any required doubt. Mass spectrometry methodologies and in particular MALDI‐ToF measurements are definitively suitable to meet the characterization requirements. In the present study, trans‐2‐[3‐(4‐t‐butyl‐phenyl)‐2‐methyl‐2‐propenylidene]malononitrile (DCTB) was shown to afford better results than the reported terthiophene and dithranol matrices as far as sensitivity and signal‐to‐noise ratio are concerned. We tentatively proposed that the ionization of the P3HT molecules is performed by charge exchange in the condensed phase (clusters) with matrix molecule radical cations and subsequent neutral matrix molecule evaporation from the clusters. The putative key parameters to account for the really high efficiency of DCTB for the MALDI analysis of P3HT are (1) the highest ionization energy of DCTB amongst the three matrices, (2) the really high absorptivity of the matrix molecule at the laser wavelength and (3) the presence of the tertiobutyl group on the matrix molecule. The presence of this substituent is likely to decrease the intermolecular interactions in the condensed phase rendering the evaporation of the neutral matrix molecules less energy demanding. We also demonstrated for polymer samples presenting an average number molecular weight (Mn) below 10 000 g mol−1 that the systematic overestimation of the low mass oligomers upon MALDI measurements ends up with wrong Mn and polydispersity index (PDI) values. A systematic Soxhlet extraction against heptane was shown to allow the recording of absolute Mn and PDI. Copyright © 2011 John Wiley & Sons, Ltd.
IRMPD and ECD fragmentation of intermolecular cross‐linked peptides
Authors: Santos Luiz Fernando Arruda , Eberlin Marcos Nogueira , Gozzo Fábio Cesar 
Published: March 2011

AbstractDespite the increasing number of studies using mass spectrometry for three dimensional analyses of proteins (MS3D), the identification of cross‐linked peptides remains a bottleneck of the method. One of the main reasons for this is the lack of knowledge about the fragmentation of these species. Intermolecular cross‐linked peptides are considered the most informative species present in MS3D experiment, since different peptides are connected by a cross‐linker, the peptides chain can be either from a single protein, providing information about protein folding, or from two different proteins in a complex, providing information about binding partners, complex topology and interaction sites. These species tend to be large and highly charged in ESI, making comprehensive fragmentation by CID MS/MS problematic. On the other hand, these highly charged peptides are very suitable for dissociation using both infrared multiphoton dissociation (IRMPD) and electron capture dissociation (ECD). Herein, we report the fragmentation study of intermolecular cross‐linked peptides using IRMPD and ECD. Using synthetic peptides and different commercial cross‐linkers, a series of intermolecular cross‐linked peptides were generate, and subsequently fragmented by IRMPD and ECD in a FT‐ICR‐MS instrument. Due to the high mass accuracy and resolution of the FT‐ICR, the fragment ions could be attributed with high confidence. The peptides sequence coverage and fragmentation features obtained from IRMPD and ECD were compared for all charge states. Copyright © 2011 John Wiley & Sons, Ltd.
Factors affecting detectability of river otters during sign surveys
Authors: Jeffress Mackenzie R. , Paukert Craig P. , Sandercock Brett K. , Gipson Philip S. 
Published: March 2011

AbstractSign surveys are commonly used to study and monitor wildlife species but may be flawed when surveys are conducted only once and cover short distances, which can lead to a lack of accountability for false absences. Multiple observers surveyed for river otter (Lontra canadensis) scat and tracks along stream and reservoir shorelines at 110 randomly selected sites in eastern Kansas from January to April 2008 and 2009 to determine if detection probability differed among substrates, sign types, observers, survey lengths, and near access points. We estimated detection probabilities (p) of river otters using occupancy models in Program PRESENCE. Mean detection probability for a 400‐m survey was highest in mud substrates (p = 0.60) and lowest in snow (p = 0.18) and leaf litter substrates (p = 0.27). Scat had a higher detection probability (p = 0.53) than tracks (p = 0.18), and experienced observers had higher detection probabilities (p > 0.71) than novice observers (p < 0.55). Detection probabilities increased almost 3‐fold as survey length increased from 200 m to 1,000 m, and otter sign was not concentrated near access points. After accounting for imperfect detection, our estimates of otter site occupancy based on a 400‐m survey increased >3‐fold, providing further evidence of the potential negative bias that can occur in estimates from sign surveys when imperfect detection is not addressed. Our study identifies areas for improvement in sign survey methodologies and results are applicable for sign surveys commonly used for many species across a range of habitats. © 2010 The Wildlife Society
Invading white‐tailed deer change wolf–caribou dynamics in northeastern Alberta
Authors: Latham A. David M. , Latham M. Cecilia , Mccutchen Nicole A. , Boutin Stan 
Published: March 2011

AbstractHuman‐caused habitat change has been implicated in current woodland caribou (Rangifer tarandus caribou) population declines across North America. Increased early seral habitat associated with industrial footprint can result in an increase in ungulate densities and subsequently those of their predator, wolves (Canis lupus). Higher wolf densities can result in increased encounters between wolves and caribou and consequently higher caribou mortality. We contrasted changes in moose (Alces alces) and deer (Odocoileusspp.) densities and assessed their effects on wolf–caribou dynamics in northeastern Alberta, Canada, pre (1994–1997) versus post (2005–2009) major industrial expansion in the region. Observable white‐tailed deer (O. virginianus) increased 17.5‐fold but moose remained unchanged. Wolf numbers also increased from approximately 6–11.5/1,000 km2. Coincident with these changes, spatial overlap between wolf pack territories and caribou range was high relative to the mid‐1990s. The high number of wolf locations in caribou range suggests that forays were not merely exploratory, but rather represented hunting forays and denning locations. Scat analysis indicated that wolf consumption of moose declined substantively during this time period, whereas use of deer increased markedly and deer replaced moose as the primary prey of wolves. Caribou increased 10‐fold in the diet of wolves and caribou population trends in the region changed from stable to declining. Wolf use of beaver (Castor canadensis) increased since the mid‐1990s. We suggest that recent declines in woodland caribou populations in the southerly extent of their range have occurred because high deer densities resulted in a numeric response by wolves and consequently higher incidental predation on caribou. Our results indicate that management actions to conserve caribou must now include deer in primary prey and wolf reduction programs. © 2010 The Wildlife Society
Non‐native species impacts on pond occupancy by an anuran
Authors: Adams Michael J. , Pearl Christopher A. , Galvan Stephanie , Mccreary Brome 
Published: March 2011

AbstractNon‐native fish and bullfrogs (Lithobates catesbeianus) are frequently cited as contributing to the decline of ranid frogs in the western United States, so we hypothesized that non‐native species, habitat, or a combination of these relate to the probability of local extinction for northern red‐legged frogs (Rana aurora) in Oregon, USA. We also hypothesized that the probability of colonization relates to land use, wetland size, or riparian forest. In a 5‐yr study, we found no support for an effect of non‐native species on northern red‐legged frogs. Instead, probability of local extinction decreased with the extent of emergent vegetation and riparian forest. This finding suggests that managers consider the role of habitat when confronting non‐native species problems. © 2010 The Wildlife Society.
Response of timber rattlesnakes to commercial logging operations
Authors: Reinert Howard K. , Munroe William F. , Brennan Curt E. , Rach Matthew N. , Pelesky Samuel , Bushar Lauretta M. 
Published: March 2011

AbstractForest management practices in the eastern United States directly impact large parcels of land that serve as habitat for timber rattlesnakes (Crotalus horridus). We assessed the behavioral response of timber rattlesnakes to commercial logging activities and the impact of such activities on a timber rattlesnake population in northcentral Pennsylvania. We radiotelemetrically monitored 67 individual snakes over periods of up to 4 years, marked and recaptured 306 snakes, and conducted search and survey efforts before, during, and after commercial logging operations on 3 timber sale parcels (totaling 154.2 ha). Location and timing of timber sales created the maximum opportunity for interaction of snakes with logging operations and with altered habitat. Observed logging‐related mortality of snakes was low (<2% of the population/yr), but potential mortality could have reached 7%. Logging activity and resulting habitat changes did not alter behavior or movement patterns of telemetrically monitored snakes. Snakes with established activity ranges in timber sale areas continued to use these areas both during and after logging operations. Similarly, snakes with activity patterns that did not include timber sale areas did not alter their movement patterns to include such sites in the short‐term. Timbering increased structural diversity of the habitat and, concurrently, diversity of habitat used by timber rattlesnakes increased. Our results suggest that the opportunity exists to develop forest management practices that provide timber products while limiting impacts on behavior and habitat use of timber rattlesnakes. To further reduce impacts to timber rattlesnake populations we recommend that management agencies require commercial logging contractors, sub‐contractors, and field employees to adhere strictly to a policy that prohibits the intentional killing of rattlesnakes encountered during logging activities. © 2010 The Wildlife Society.
General treatment of a kinetic scheme with chain length dependent termination
Authors: Oskar Friedrich Olaj , Zifferer Gerhard 
Published: March 2011

AbstractWithout making reference to any special type of the dependence of the rate constant of bimolecular termination kt (m,n) on the chain lengths (m and n) of the two radicals involved universal relations are derived between the basic quantities characteristic of the polymerization kinetics of such a system. In case kt (m,n) can be factorized simple expressions may be obtained also if termination is by recombination. These universal relationships have been successfully tested for a power, law dependence of kt on various means m̄,n̄, kt = kt °(m̄,n̄)−b. Their use provides comfortable access to resolving the kinetic scheme. Thus, for the geometric mean, m̄,n̄ = √mn, in its long chain approximation a complete resolution of a kinetic scheme including chain transfer could be worked out, which is free from any further assumptions. In addition, the numeric results obtained for various means m̄,n̄ are discussed and analyzed with respect to the possibility of obtaining experimental information on which type of mean m̄,n̄ is operative in the bimolecular termination process of free radical polymerization. In a further effort it is shown for some selected examples that any individual functional dependence of kt on m and n will coincide with that for the apparent (i.e. experimentally detectable) termination constant on (average) degree of polymerization of dead polymer, k̄t (P̄), as long as kt is a continuous and monotonous function of m and n.
Initiators of cationic polymerization of olefins arising from interaction between two lewis acids
Authors: Marek M. , Pecka J. , Halaška V. 
Published: March 2011

AbstractBy an interaction between two relatively weak Lewis acids, highly effective initiators of the cationic polymerization of olefins are obtained. Under conditions where the polymerization of isobutylene with BCl3, TiCl4 or VOCl3 does not proceed in methylene chloride or heptane solution, it can be initiated with a small or even trace quantity of FeCl3. The formation of complex compounds was investigated by UV spectroscopy and by the conductometric titration in methylene chloride. Hydrogen chloride, which has no co‐initiation effect on polymerization in heptane solution initiated with metal halides alone, is an effective co‐initiator in a mixture of Lewis acids containing a small quantity of FeCl3. The results support a hypothesis regarding the initiation of polymerization of olefins by cations of metal halides arising by the ionization of a weaker acid with a stronger one.
Some reactions of polymers
Authors: Bevington John C. , Thorpe F. Gordon 
Published: March 2011

AbstractThree topics are discussed. First, structural irregularities are considered in connection with polyformaldehyde,. poly(vinyl chloride) and poly(vinyl acetate) and with the stabilities of polymers in general. The second topic concerns the distribution of sites of reaction when polymers are modified chemically. The final section deals briefly with polymeric reagents, including some designed for photochemical systems.
A modified method for the acid hydrolysis of grafted cellulose
Authors: Fernández M. J. , Casinos I. , Guzmán G. M. 
Published: March 2011

AbstractThe hydrolytic method using 72% sulphuric acid was modified in order to characterize the graft copolymer cellulose‐g‐poly(vinyl acetate‐co‐methyl acrylate). This method involves appropriate cellulose hydrolysis conditions, and the extraction of a fraction of cellulose only when the samples have a low ratio of synthetic polymer to cellulose. In this way, an undesired chemical transformation of the grafted chains is avoided and the polysaccharide is completely removed from the synthetic polymer. This method might be extended to other cellulosic graft copolymers whose carbohydrate part cannot be completely separated and their grafted chains are labile in the reaction conditions reported in the literature.