bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stiffness of photocrosslinked RGD‐alginate gels regulates adipose progenitor cell behavior
Authors: Chandler Emily M. , Berglund Caroline M. , Lee Jason S. , Polacheck William J. , Gleghorn Jason P. , Kirby Brian J. , Fischbach Claudia 
Published: February 2011

AbstractAdipose progenitor cells (APCs) are widely investigated for soft tissue reconstruction following tumor resection; however, the long‐term success of current approaches is still limited. In order to develop clinically relevant therapies, a better understanding of the role of cell–microenvironment interactions in adipose tissue regeneration is essential. In particular, the effect of extracellular matrix (ECM) mechanics on the regenerative capability of APCs remains to be clarified. We have used artificial ECMs based on photocrosslinkable RGD‐alginate to investigate the adipogenic and pro‐angiogenic potential of 3T3‐L1 preadipocytes as a function of matrix stiffness. These hydrogels allowed us to decouple matrix stiffness from changes in adhesion peptide density or extracellular Ca2+ concentration and provided a physiologically relevant 3D culture context. Our findings suggest that increased matrix rigidity promotes APC self‐renewal and angiogenic capacity, whereas, it inhibits adipose differentiation. Collectively, this study advances our understanding of the role of ECM mechanics in adipose tissue formation and vascularization and will aid in the design of efficacious biomaterial scaffolds for adipose tissue engineering applications. Biotechnol. Bioeng. 2011; 108:1683–1692. © 2011 Wiley Periodicals, Inc.
Palladium(II)‐Mediated Assembly of Biotinylated Ion Channels
Authors: Wilson Craig P. , Boglio Cécile , Ma Long , Cockroft Scott L. , Webb Simon J. 
Published: February 2011

AbstractSimple synthetic methodology has been used to create biotinylated pyridyl cholate lipids that can undergo multiple self‐assembly events when inserted into phospholipid vesicles; PdII links cholates into transmembrane lipids, while avidin laterally clusters these complexes together and concomitantly assembles the vesicles into aggregates. The transmembrane assembly of cholates by PdII “opened” the ion channels, whereas avidin addition produced vesicle aggregates, giving a system that mimicked both transmembrane transport and cellular adhesion. Complexation of these PdII‐linked cholates by avidin gave a measurable decrease in ion flow, suggesting some channels became blocked or were prevented from adopting the optimum geometry for ion conduction. This reflects the importance of spatially appropriate preorganisation when generating active supramolecular assemblies.
Surface Chemistry in the Process of Coating Mesoporous SiO2 onto Carbon Nanotubes Driven by the Formation of SiOC Bonds
Authors: Paula Amauri J. , Stéfani Diego , Souza Filho Antonio G. , Kim Yoong Ahm , Endo Morinobu , Alves Oswaldo L. 
Published: February 2011

AbstractThe deposition of mesoporous silica (SiO2) on carbon nanotubes (CNTs) has opened up a wide range of assembling possibilities by exploiting the sidewall of CNTs and organosilane chemistry. The resulting systems may be suitable for applications in catalysis, energy conversion, environmental chemistry, and nanomedicine. However, to promote the condensation of silicon monomers on the nanotube without producing segregated particles, (OR)4−xSiOxx− units must undergo nucleophilic substitution by groups localized on the CNT sidewall during the transesterification reaction. In order to achieve this preferential attachment, we have deposited silica on oxidized carbon nanotubes (single‐walled and multiwalled) in a sol–gel process that also involved the use of a soft template (cetyltrimethylammonium bromide, CTAB). In contrast to the simple approach normally used to describe the attachment of inorganic compounds on CNTs, SiO2 nucleation on the tube is a result of nucleophilic attack mainly by hydroxyl radicals, localized in a very complex surface chemical environment, where various oxygenated groups are covalently bonded to the sidewall and carboxylated carbonaceous fragments (CCFs) are adsorbed on the tubes. SiOC covalent bond formation in the SiO2–CNT hybrids was observed even after removal of the CCFs with sodium hydroxide. By adding CTAB, and increasing the temperature, time, and initial amount of the catalyst (NH4OH) in the synthesis, the SiO2 coating morphology could be changed from one of nanoparticles to mesoporous shells. Concomitantly, pore ordering was achieved by increasing the amount of CTAB. Furthermore, preferential attachment on the sidewall results mostly in CNTs with uncapped ends, having sites (carboxylic acids) that can be used for further localized reactions.
Exciton‐Coupled Charge‐Transfer Dynamics in a Porphyrin J‐Aggregate/TiO2 Complex
Authors: Verma Sandeep , Ghosh Amrita , Das Amitava , Ghosh Hirendra N. 
Published: February 2011

AbstractExciton‐coupled charge‐transfer (CT) dynamics in TiO2 nanoparticles (NP) sensitized with porphyrin J‐aggregates has been studied by femtosecond time‐resolved transient absorption spectroscopy. J‐aggregates of 5,10,15‐triphenyl‐20‐(3,4‐dihydroxyphenyl) porphyrin (TPPcat) form CT complexes on TiO2 NP surfaces. Catechol‐mediated strong CT coupling between J‐aggregate and TiO2 NP facilitates interfacial exciton dissociation for electron injection into the conduction band of the TiO2 nanoparticle in pulse width limited time (<80 fs). Here, the electron‐transfer (<80 fs) process dominates over the intrinsic exciton‐relaxation process (J‐aggregates: ca. 200 fs) on account of exciton‐coupled CT interaction. The parent hole on J‐aggregates is delocalized through J‐aggregate excitonic coherence. As a result, holes immobilized on J‐aggregates are spatially less accessible to electrons injected into TiO2, and thus the back electron transfer (BET) process is slower than that of the monomer/TiO2 system. The J‐aggregate/porphyrin system shows exciton spectral and temporal properties for better charge separation in strongly coupled composite systems.
Coupled Crystallographic Order–Disorder and Spin State in a Bistable Molecule: Multiple Transition Dynamics
Authors: Craig Gavin A. , Sánchez Costa José , Roubeau Olivier , Teat Simon J. , Aromí Guillem 
Published: February 2011

AbstractA novel bispyrazolylpyridine ligand incorporating lateral phenol groups, H4L, has led to an FeII spin‐crossover (SCO) complex, [Fe(H4L)2][ClO4]2⋅H2O⋅2 (CH3)2CO (1), with an intricate network of intermolecular interactions. It exhibits a 40 K wide hysteresis of magnetization as a result of the spin transition (with T0.5 of 133 and 173 K) and features an unsymmetrical and very rich structure. The latter is a consequence of the coupling between the SCO and the crystallographic transformations. The high‐spin state may also be thermally trapped, exhibiting a very large TTIESST (≈104 K). The structure of 1 has been determined at various temperatures after submitting the crystal to different processes to recreate the key points of the hysteresis cycle and thermal trapping; 200 K, cooled to 150 K and trapped at 100 K (high spin, HS), slowly cooled to 100 K and warmed to 150 K (low spin, LS). In the HS state, the system always exhibits disorder for some components (one ClO4− and two acetone molecules) whereas the LS phases show a relative ≈9 % reduction in the FeN bond lengths and anisotropic contraction of the unit cell. Most importantly, in the LS state all the species are always found to be ordered. Therefore, the bistability of crystallographic order–disorder coupled to SCO is demonstrated here experimentally for the first time. The variation in the cell parameters in 1 also exhibits hysteresis. The structural and magnetic thermal variations in this compound are paralleled by changes in the heat capacity as measured by differential scanning calorimetry. Attempts to simulate the asymmetric SCO behaviour of 1 by using an Ising‐like model underscore the paramount role of dynamics in the coupling between the SCO and the crystallographic transitions.
PAX8 is expressed in pancreatic well‐differentiated neuroendocrine tumors and in extrapancreatic poorly differentiated neuroendocrine carcinomas in fine‐needle aspiration biopsy specimens
Authors: Haynes Claudia M. , Sangoi Ankur R. , Pai Reetesh K. 
Published: February 2011

AbstractBACKGROUND:PAX (paired box) genes encode a family of transcription factors important for organogenesis. Recently, PAX8 has been recognized as a potential immunohistochemical marker of pancreatic neuroendocrine tumors. The authors evaluated PAX8 expression in fine‐needle aspiration biopsies of neuroendocrine tumors to establish whether PAX8 immunohistochemistry can be used as an ancillary marker of pancreatic origin for neuroendocrine tumors.METHODS:Fine‐needle aspiration biopsies from 72 neuroendocrine tumors were evaluated for PAX8 expression: 32 primary and 23 metastatic well‐differentiated neuroendocrine tumors (25 pancreatic, 13 pulmonary, 3 ileal, 2 duodenal, 1 rectal, 1 ovarian, and 10 primary site unknown) and 17 poorly differentiated neuroendocrine carcinomas (11 pulmonary, 1 pancreas, 1 breast, 1 thymus, and 3 primary site unknown).RESULTS:Among well‐differentiated neuroendocrine tumors, only tumors from the pancreas were PAX8 positive (14 of 25, 56%) whereas no cases of pulmonary (0 of 13), ileal (0 of 3), duodenal (0 of 2), rectal (0 of 1), or ovarian (0 of 1) well‐differentiated neuroendocrine tumors were positive for PAX8. One of 10 (10%) well‐differentiated neuroendocrine tumors of unknown primary origin was PAX8 positive. Among poorly differentiated neuroendocrine carcinomas, PAX8 expression was identified in 1 of 1 (100%) pancreatic, 1 of 1 (100%) thymic, 4 of 11 (36%) pulmonary, and 0 of 1 (0%) breast carcinomas. One of 3 (33%) poorly differentiated neuroendocrine carcinomas of unknown primary origin was PAX8 positive.CONCLUSIONS:Pancreatic well‐differentiated neuroendocrine tumors frequently express PAX8, which can help distinguish pancreatic primary tumors from tumors of other anatomic sites. In contrast, PAX8 expression in poorly differentiated neuroendocrine carcinomas is not specific for pancreatic origin and can be seen in extrapancreatic poorly differentiated neuroendocrine carcinomas. Cancer (Cancer Cytopathol) 2011;. © 2011 American Cancer Society
Elastic management of web server clusters on distributed virtual infrastructures
Authors: Moreno‐Vozmediano Rafael , Montero Ruben S. , Llorente Ignacio M. 
Published: February 2011

AbstractCluster‐based solutions are being widely adopted for implementing flexible, scalable, low‐cost and high‐performance web server platforms. One of the main difficulties to implement these platforms is the correct dimensioning of the cluster size, so as to satisfy variable and peak demand periods. In this context, virtualization is being adopted by many organizations as a solution not only to provide service elasticity, but also to consolidate server workloads, and improve server utilization rates. A virtualized web server can be dynamically adapted to the client demands by deploying new virtual nodes when the demand increases, and powering off and consolidating virtual nodes during periods of low demand. Furthermore, the resources from the in‐house infrastructure can be complemented with a cloud provider (cloud bursting), so that peak demand periods can be satisfied by deploying cluster nodes in the external cloud, on an on‐demand basis. In this paper, we analyze the scalability of hybrid virtual infrastructures for two different distributed web server cluster implementations: a simple web cluster serving static files and a multi‐tier web server platform running the CloudStone benchmark. Copyright © 2011 John Wiley & Sons, Ltd.
How Förster Resonance Energy Transfer Imaging Improves the Understanding of Protein Interaction Networks in Cancer Biology
Authors: Fruhwirth Gilbert O. , Fernandes Luis P. , Weitsman Gregory , Patel Gargi , Kelleher Muireann , Lawler Katherine , Brock Adrian , Poland Simon P. , Matthews Daniel R. , Kéri György , Barber Paul R. , Vojnovic Borivoj , Ameer‐Beg Simon M. , Coolen Anthony C. C. , Fraternali Franca , Ng Tony 
Published: February 2011

AbstractHerein we discuss how FRET imaging can contribute at various stages to delineate the function of the proteome. Therefore, we briefly describe FRET imaging techniques, the selection of suitable FRET pairs and potential caveats. Furthermore, we discuss state‐of‐the‐art FRET‐based screening approaches (underpinned by protein interaction network analysis using computational biology) and preclinical intravital FRET‐imaging techniques that can be used for functional validation of candidate hits (nodes and edges) from the network screen, as well as measurement of the efficacy of perturbing these nodes/edges by short hairpin RNA (shRNA) and/or small molecule‐based approaches.
Direct examination of chromosomal clustering of organ‐specific genes in the chordate Ciona intestinalis
Authors: Shoguchi Eiichi , Hamada Mayuko , Fujie Manabu , Satoh Nori 
Published: February 2011

AbstractOne of challenges in the field of developmental biology is to understand how spatially and/or temporally coordinated expression of genes is controlled at the chromosomal level. It remains controversial whether genes expressed in a given tissue are randomly distributed throughout a given animal genome, or instead resolve into clusters. Here we used microarray analysis to identify more than 1,700 genes that are expressed preferentially in each of 11 organs of the chordate Ciona intestinalis adult, and determined the location of these genes on the 14 pairs of Ciona chromosomes. In spite of extensive mapped gene analysis, we only confirmed small clusters containing two or three genes. Our result indicates that organ‐specific genes are distributed rather evenly all over chromosomes, suggesting that the notion of clustering of organ‐specific genes in animal genomes is not generally applicable to this chordate. genesis 49:662–672, 2011. © 2011 Wiley‐Liss, Inc.
Characteristic Analysis of a Micro DC‐DC Converter for Portable Electronic Devices and an Improvement of Transient Response Characteristic
Authors: Sugahara Satoshi , Yamada Kouhei , Nishio Haruhiko , Edo Masaharu , Sato Toshiro , Yamasawa Kiyohito 
Published: February 2011

AbstractThis paper describes the characteristic analysis of a micro DC‐DC converter which integrates inductor, controller and switching devices, and the improvement of the transient response characteristic. The steady‐state operation and the efficiency characteristics of the micro DC‐DC converter are presented as experimental data. The static characteristics are theoretically analyzed with consideration of the DC current characteristics of the inductor. The load transient response characteristics of the micro DC‐DC converter are also analyzed experimentally and theoretically. In addition, the factors responsible for the overshoot and undershoot of the output voltage when the load changes are discussed. Finally, a clamp circuit for reducing the overshoot and undershoot of the output voltage when the load changes is proposed. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(3): 56–64, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21081
Crystal Structures and Conductivities of Two Organic–Inorganic Hybrid Complexes Based on Poly‐Keggin‐Anion Chains
Authors: Wei Mei‐Lin , Zhuang Peng‐Fei , Li Hui‐Hua , Yang Yun‐Hui 
Published: February 2011

AbstractTwo proton‐conducting organic–inorganic hybrid complexes have been constructed by the self‐assembly of protonated water clusters, transition‐metal aqua ions, [PMo12O40]3– anions and isonicotinic acid N‐oxide (HINO). Single‐crystal X‐ray diffraction analyses at 293 K revealed that both complexes presented exactly the same three‐dimensional supramolecular framework built from non‐covalent interactions. Interestingly, the [PMo12O40]3– anions self‐assembled into poly‐Keggin‐anion chains in the supramolecular frameworks. Thermogravimetric analyses showed no weight loss for either system in the temperature range of 20–100 °C, which indicates that none of the water molecules in the unit structure are easily lost below 100 °C. Surprisingly, the proton conductivities of 1 and 2 in the temperature range of 85–100 °C under 98 % relative humidity reached good proton conductivities of 10–3 S cm–1. A possible mechanism for the proton conduction in accord with experimental results is proposed.
Synthesis, Structure and Bactericide Activity of (Aminophosphane)gold(I) Thiolate Complexes
Authors: Fillat María F. , Gimeno M. Concepción , Laguna Antonio , Latorre Encarnación , Ortego Lourdes , Villacampa M. Dolores 
Published: February 2011

AbstractReaction of the aminophosphane ligands 2‐(diphenylphosphanylamino)pyridine (Ph2PNHpy, 1) and 3‐(diphenylphosphanylamino)‐1,2,4‐triazole [Ph2PNH(Htrz), 2] with the gold(I) compound [AuCl(tht)] (tht = tetrahydrothiophene) gave the complexes [AuCl(Ph2PNHpy)] (3) and [AuCl{Ph2PNH(Htrz)}] (4), respectively. A series of new gold(I) thiolate derivatives were synthesized from the reactions of complex 3 or 4 with 1 equiv. of a deprotonated thiol ligand. Complexes [Au(SR)(PPh2NHpy)] (5–8) were prepared by reaction of complex 3 with the corresponding thiol HSR [HSR = 2‐mercaptopyridine (2‐HSpy), 2‐mercaptonicotinic acid (2‐H2‐mna), 2‐thiouracil (2‐HTU) or 2‐thiocytosine (2‐HTC)] in the presence of sodium carbonate or triethylamine. Complexes [Au(SR){PPh2NH(Htrz)}] (9–11) were prepared by the treatment of complex 4 with triethylamine and the respective thiol HSR [HSR = 2‐mercaptopyridine (2‐HSpy), 2‐thiocytosine (2‐HTC) or 6‐thioguanine (6‐HTG)]. The susceptibility of Enterococcus faecalis ATCC25923, Staphylococcus aureus ATCC29213 and Escherichia coli TG1 towards the synthesized gold(I) complexes was evaluated. Some of them exhibit powerful anti‐bacterial activity, being more efficient against Gram‐positive microorganisms. Complexes 7–9 and 11 present excellent activity against E. faecalis, whereas the highest sensitivity of S. aureus was against complexes 7 and 8. The structures of complexes 4, 5, 8 and 9 were determined by X‐ray structural analysis. None of the four compounds shows aurophilic interactions between the gold(I) centres in the crystals. The four complexes possess intermolecular hydrogen bonds that lead to supramolecular arrangements.
Fatty acids and polar lipid content of cheese and mould‐contaminated cheese
Authors: Schlosser Sonja , Vetter Walter 
Published: February 2011

AbstractUnintended infestation of food with viable mould irreversibly leads to spoilage of food. However, little data existed on the fatty acid composition and polar lipid content of mould grown on cheese and the potential influence of these parameters in mould‐infested cheese. In this study, we thus focused on the fatty acids composition and polar lipid content of cheese, mould isolated from mould‐infested cheese, as well as inoculation of cheese with cultures of isolated moulds. For this purpose, we stored three cheese samples (gouda, brown cheese, and parmesan) over extended periods in order to force mould infestation from air. The moulds grown on gouda and brown cheese were identified as Penicillium brevicompactum and Penicillium roqueforti, respectively, while a mixed culture was obtained from parmesan. From these contaminated samples, mould spores were isolated and cultivated. Finally, the (pure) cheeses were inoculated with mould spores. Three subsamples, (1) cheeses, (2) moulds isolated from cheese, and (3) cheeses infested with the isolated moulds were studied with regards to their fatty acid distribution in the neutral and the polar lipids. The different amounts of polar lipids of cheese (0.39–2%), moulds (11–30.7%), and mould‐infested cheese (1.5–5%) allowed calculating the mould content of the mould‐infested cheeses.
ZNF703 gene amplification at 8p12 specifies luminal B breast cancer
Authors: Sircoulomb Fabrice , Nicolas Nathalie , Ferrari Anthony , Finetti Pascal , Bekhouche Ismahane , Rousselet Estelle , Lonigro Aurélie , Adélaïde José , Baudelet Emilie , Esteyriès Séverine , Wicinski Julien , Audebert Stéphane , Charafe‐Jauffret Emmanuelle , Jacquemier Jocelyne , Lopez Marc , Borg Jean‐Paul , Sotiriou Christos , Popovici Cornel , Bertucci François , Birnbaum Daniel , Chaffanet Max , Ginestier Christophe 
Published: February 2011

AbstractLuminal B breast cancers represent a fraction of oestrogen receptor (ER)‐positive tumours associated with poor recurrence‐free and disease‐specific survival in all adjuvant systemic treatment categories including hormone therapy alone. Identification of specific signalling pathways driving luminal B biology is paramount to improve treatment. We have studied 100 luminal breast tumours by combined analysis of genome copy number aberrations and gene expression. We show that amplification of the ZNF703 gene, located in chromosomal region 8p12, preferentially occurs in luminal B tumours. We explored the functional role of ZNF703 in luminal B tumours by overexpressing ZNF703 in the MCF7 luminal cell line. Using mass spectrometry, we identified ZNF703 as a co‐factor of a nuclear complex comprising DCAF7, PHB2 and NCOR2. ZNF703 expression results in the activation of stem cell‐related gene expression leading to an increase in cancer stem cells. Moreover, we show that ZNF703 is implicated in the regulation of ER and E2F1 transcription factor. These findings point out the prominent role of ZNF703 in transcription modulation, stem cell regulation and luminal B oncogenesis.→See accompanying Closeup by Vessela Kristensen DOI 10.1002/emmm201100128
Does the EU sugar policy reform increase added sugar consumption? An empirical evidence on the soft drink market
Authors: Bonnet Céline , Requillart Vincent 
Published: February 2011

AbstractWhereas National Health authorities recommend a decrease in the consumption of ‘added’ sugar, a reform on the sugar market will lead to a 36% decrease of the sugar price in the EU. Using French data on soft drinks purchases, this paper investigates the anticipated impact of this reform on the consumption of sugar‐sweetened beverages. The reform of the EU sugar policy leads to a decrease in regular soft drink prices by 3% and varies across brands. To assess substitution within this food category, we use a random‐coefficients logit model that takes into account a large number of differentiated products and heterogeneity in consumers' behavior. Results suggest that price changes would lead to an increase in market shares of regular products by 7.5% and to substitutions between brands to the benefit of products with the highest sugar content. On the whole, it would raise consumption of regular soft drinks by more than 1 litre per person per year and consumption of added sugar by 124 g per person per year, this increase being larger in households composed of overweight and obese individuals. Copyright © 2011 John Wiley & Sons, Ltd.