bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of phorbol ester‐sensitive PKC (c/nPKC) activation on the production of adiponectin in 3T3‐L1 adipocytes
Authors: Ikeda Takahide , Kajita Kazuo , Zhiliang Wu , Hanamoto Takayuki , Mori Ichiro , Fujioka Kei , Okada Hideyuki , Fujikake Takatoshi , Uno Yoshihiro , Morita Hiroyuki , Nagano Isao , Takahashi Yuzo , Ishizuka Tatsuo 
Published: May 2009

AbstractPPARγ plays a key role in adipocyte specific gene expression. In this study, we assessed the effects of phorbol ester (TPA)‐sensitive PKC (c/nPKC) activation on the expression of adipocyte specific genes and inflammation related genes. Treatment with both TPA and TNFα decreased mRNA levels of PPARγ, aP2, LPL and adiponectin. TNFα, but not TPA, increased IL‐6 and MCP‐1 mRNA levels, Next, we investigated the effects of ligands which activate c/nPKC. Insulin and angiotensin II (AII), but not high glucose, reduced PPARγ, aP2 and adiponectin mRNA levels. AII‐induced suppression of these genes was restored in the presence of Go6976, a specific c/nPKC inhibitor, and candesartan, an AII receptor blocker. The effect of reduced insulin was prevented by Go6976 and LY294002, a specific PI 3‐kinase inhibitors. Our results indicate that activation of c/nPKC could debilitate and/or might deteriorate insulin sensitivity in vivo, through the reduction of PPARγ and adiponectin expression in adipocyte. © 2009 IUBMB IUBMB Life, 61(6): 644–650, 2009
Mechanism of growth inhibition by MicroRNA 145: The role of the IGF‐I receptor signaling pathway
Authors: La Rocca Gaspare , Badin Margherita , Shi Bin , Xu Shi‐Qiong , DeAngelis Tiziana , Sepp‐Lorenzinoi Laura , Baserga Renato 
Published: May 2009

AbstractMicroRNA 145 (miR145) has been proposed as a tumor suppressor. It was previously shown that miR145 targets the 3′ UTR of the insulin receptor substrate‐1 (IRS‐1) and dramatically inhibits the growth of colon cancer cells. miR145 also targets the type 1 insulin‐like growth factor receptor (IGF‐IR). We show here that an IRS‐1 lacking its 3′ UTR is no longer down‐regulated by miR145 and rescues colon cancer cells from miR145‐induced inhibition of growth. An IGF‐IR resistant to miR145 (again by elimination of its 3′ UTR) is not down‐regulated by miR145 but fails to rescue colon cancer cells from growth inhibition. These and other results, taken together, indicate that down‐regulation of IRS‐1 plays a significant role in the tumor suppressor activity of miR145. J. Cell. Physiol. 220: 485–491, 2009. © 2009 Wiley‐Liss, Inc.
Measurement of deep gray matter perfusion using a segmented true–fast imaging with steady‐state precession (True‐FISP) arterial spin‐labeling (ASL) method at 3T
Authors: Grossman Elan J. , Zhang Ke , An Jing , Voorhees Abram , Inglese Matilda , Ge Yulin , Oesingmann Niels , Xu Jian , Mcgorty Kelly A. , Chen Qun 
Published: May 2009

AbstractPurposeTo study the feasibility of using the MRI technique of segmented true–fast imaging with steady‐state precession arterial spin‐labeling (True‐FISP ASL) for the noninvasive measurement and quantification of local perfusion in cerebral deep gray matter at 3T.Materials and MethodsA flow‐sensitive alternating inversion‐recovery (FAIR) ASL perfusion preparation was used in which the echo‐planar imaging (EPI) readout was replaced with a segmented True‐FISP data acquisition strategy. The absolute perfusion for six selected regions of deep gray matter (left and right thalamus, putamen, and caudate) were calculated in 11 healthy human subjects (six male, five female; mean age = 35.5 years ± 9.9).ResultsPreliminary measurements of the average absolute perfusion values at the six selected regions of deep gray matter are in agreement with published values for mean absolute cerebral blood flow (CBF) baselines acquired from healthy volunteers using positron emission tomography (PET).ConclusionSegmented True‐FISP ASL is a practical and quantitative technique suitable to measure local tissue perfusion in cerebral deep gray matter at a high spatial resolution without the susceptibility artifacts commonly associated with EPI‐based methods of ASL. J. Magn. Reson. Imaging 2009;29:1425–1431. © 2009 Wiley‐Liss, Inc.
Contribution of Kv channel subunits to glutamate‐induced apoptosis in cultured rat hippocampal neurons
Authors: Shen Qi‐Jun , Zhao Yu‐Ming , Cao Dong‐Xu , Wang Xiao‐Liang 
Published: May 2009

AbstractPotassium channel dysfunction has been implicated in apoptosis in many pathological conditions. However, which Kv channel subunit is involved in glutamate‐induced apoptosis remains unknown. In this study, the contributions of nine Kvα and three Kvβ subunits to glutamate‐induced hippocampal neuronal apoptosis were investigated. Results showed that neuronal apoptosis was not obvious with 12 hr incubation of glutamate but increased markedly after 18 hr, which was attenuated by the Kv channel blocker TEA. Among all the Kv subunits investigated, gene and protein expression of Kv2.1 increased significantly before the appearance of neuronal apoptosis, whereas the Kv1.1 mRNA level decreased quickly, and protein expression was reduced gradually after the insult. Seven other Kvα subunits and three Kvβ subunits were not obviously affected over time. In addition, Kv1.1 overexpression could reduce glutamate‐induced hippocampal neuronal apoptosis. Therefore, the alterations of Kv1.1 and Kv2.1 might contribute to glutamate‐induced toxicity in hippocampal neurons. These findings suggest that these two Kv channel subunits may represent potential therapeutic targets for neuropathological conditions in which glutamate‐induced toxicity is thought to contribute to neuronal dysfunction. © 2009 Wiley‐Liss, Inc.
Sonic hedgehog promotes the generation of myelin proteins by transplanted oligosphere‐derived cells
Authors: Gibney Sinead M. , McDermott Kieran W. 
Published: May 2009

AbstractThe generation of large numbers of functionally relevant cells for transplantation remains central to the use of cell replacement as a therapeutic strategy for neurodegenerative diseases. In this study we have analyzed the effect of sonic hedgehog (Shh) pretreatment on the myelinating potential of transplanted oligosphere‐derived cells. The retina was chosen as a model for assessing this myelinating capability because 1) there is a lack of endogenous myelin in the normal rodent retina and 2) the retinal ganglion cell (RGC) axons are receptive to myelination, once myelinating cells have access to the retinal nerve fiber layer. Initially, oligospheres were generated in the presence of B104 CM but without the addition of Shh. After transplantation, 60% of the animals developed tumors in the eye that had received the transplant and were not analyzed for the presence of myelin. In the remaining retinas, the transplanted oligosphere‐derived cells were not myelin competent, as indicated by the absence of myelin proteins in the retinal nerve fiber layer. In contrast, when B104 CM oligospheres were generated in the presence of Shh, myelin proteins were found in the nerve fiber layer after transplantation. In addition, the amount of myelin proteins synthesized increased with time posttransplantation, with the majority of the nerve fiber layer immunoreactive for these proteins in some retinas after 2 months. This study has demonstrated that growth as oligospheres and endogenously derived growth/differentiation factors alone are not sufficient to induce the differentiation of B104‐treated oligosphere‐derived cells and that pretreating the oligospheres by growth in the presence of Shh before transplantation is essential to induce their myelinating competence. © 2009 Wiley‐Liss, Inc.
Raman investigations of TiO2 nanotube substrates covered with thin Ag or Cu deposits
Authors: Roguska A. , Kudelski A. , Pisarek M. , Lewandowska M. , Dolata M. , Janik‐Czachor M. 
Published: May 2009

AbstractA tubular array of TiO2 nanotubes on Ti matrix was used as a support for Ag or Cu sputter‐deposited layers intended for surface‐enhanced Raman scattering (SERS) investigations. The composite samples of Ag/TiO2–nanotube/Ti and Cu/TiO2–nanotube/Ti were studied with the aid of scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) [and scanning Auger microscopy (SAM)] to reveal their characteristic morphological and chemical features. Raman spectra of pyridine (as a probe molecule) were measured after it had been adsorbed on the TiO2–nanotube/Ti substrates covered with thin Ag or Cu deposit as well as on the bulk electrochemically roughened Ag or Cu reference substrates. It was found that the SERS spectra measured for pyridine adsorbed on the bulk silver substrate were significantly different than the spectra measured on the TiO2–nanotube/Ti substrates covered the Ag layer. The spectra measured for pyridine adsorbed on the Ag/TiO2–nanotube/Ti suggest that on the surface of such a composite substrate there are many Lewis acidic sites. Spectra typical for pyridine adsorbed on acidic sites were observed even after deposition of a relatively thick silver layer (e.g. an Ag layer with an average thickness of 80 nm) on the TiO2–nanotube/Ti support. Our findings suggest that TiO2–nanotube/Ti support is a promising substrate for the preparation of metallic nano‐clusters on a support containing acidic active sites. Copyright © 2009 John Wiley & Sons, Ltd.
Structural role of polyethylene glycol in the formation of anatase nanocrystalline titania at low temperature
Authors: Priya Srinivasan , Balaji Subramanian , Djaoued Yahia , Robichaud Jacques 
Published: May 2009

AbstractAnatase nanocrystalline TiO2 thin films were obtained by a sol–gel dip‐coating method, in which the nanocrystallization is effected by a simple hot water treatment of the deposited films at temperatures below 90 °C under atmospheric pressure for 1 h. The dip‐coating sol was prepared by reacting titanium tetra‐n‐butoxide [Ti(OnBu)4] with polyethylene glycol (PEG) in ethanol. Films obtained from a sol that do not contain PEG show no sign of crystallization, demonstrating the importance of PEG in the crystallization process. Raman studies of reaction dynamics show that PEG undergoes a nucleophilic substitution reaction replacing butoxy groups in Ti(OnBu)4. Stoichiometric reactions of Ti(OnBu)4 with PEG in polar and nonpolar solvents were performed, and they yielded different titanium–PEG hybrid polymers, which were isolated and characterized by various spectroscopic techniques such as IR, Raman, solid‐state NMR and MALDI‐TOF‐MS. NMR studies evidenced the location and the way in which PEG is bonded with titanium atoms in the titanium–PEG hybrid polymers. On the basis of these studies, we have proposed structures for these polymers. It is demonstrated that the structure of the obtained polymers plays an important role in the formation of anatase TiO2 nanoparticles in hot water at temperatures below 90 °C under atmospheric pressure. Copyright © 2009 John Wiley & Sons, Ltd.
Computational structural analysis of an anti‐L‐amino acid antibody and inversion of its stereoselectivity
Authors: Ranieri Daniel I. , Hofstetter Heike , Hofstetter Oliver 
Published: May 2009

AbstractThe binding site of a monoclonal anti‐L‐amino acid antibody (anti‐L‐AA) was modeled using the program SWISS‐MODEL. Docking experiments with the enantiomers of phenylalanine revealed that the antibody interacts with L‐phenylalanine via hydrogen bonds and hydrophobic contacts, whereas the D‐enantiomer is rejected due to steric hindrance. Comparison of the sequences of this antibody and an anti‐D‐amino acid antibody (anti‐D‐AA) indicates that both immunoglobulins derived from the same germline progenitor. Substitution of four amino acids residues, three in the framework and one in the complementarity determining regions (CDRs), allowed in silico conversion of the anti‐L‐AA into an antibody that stereoselectively binds D‐phenylalanine.
Noncompetitive peak decay analysis of drug–protein dissociation by high‐performance affinity chromatography
Authors: Chen Jianzhong , Schiel John E. , Hage David S. 
Published: May 2009

AbstractThe peak decay method is an affinity chromatographic technique that has been used to examine the dissociation of solutes from immobilized ligands in the presence of excess displacing agent. However, it can be difficult to find a displacing agent that does not interfere with detection of the eluting analyte. In this study, a noncompetitive peak decay method was developed in which no displacing agent was required for analyte elution. This method was evaluated for the study of drug–protein interactions by using it along with high‐performance affinity chromatography to measure the dissociation rate constants forR‐ andS‐warfarin from columns containing immobilized HSA. Several factors were considered in the optimization of this method, including the amount of applied analyte, the column size, and the flow rate. The dissociation rate constants forR‐ andS‐warfarin from HSA were measured at several temperatures by this approach, giving values of 0.56 (±0.01) and 0.66 (±0.01) s–1at pH 7.4 and 37°C. These results were in good agreement with previous values obtained by other methods. This approach is not limited to warfarin and HSA but could be employed in studying additional drug–protein interactions or other systems with weak‐to‐moderate binding.
Molecularly imprinted polymers as affinity‐based separation media for sample preparation
Authors: Haginaka Jun 
Published: May 2009

AbstractThis review article deals with molecularly imprinted polymers (MIPs) as affinity‐based separation media for sample preparation. An over view of two types of MIPs (molecularly imprinted particle and monolith) used for the sample preparation and modes of molecularly imprinted SPE (online mode, offline mode, on‐column extraction, SPME, and microextraction in packed syringe) is given, focusing on the advantages and disadvantages of these types and modes. Next, problems (template leakage and incompatibility with aqueous conditions) associated with molecularly imprinted SPE and how to overcome those problems are described. Finally, pharmaceutical, food, bioanalytical, and environmental application of molecularly imprinted SPE will be discussed.
Synthesis of polyetherols with isocyanuric ring. Kinetics and mechanisms of reactions, part 1: Reaction between isocyanuric acid and ethylene carbonate
Authors: Lubczak Jacek , Węglowska Elwira 
Published: May 2009

AbstractThe reaction between isocyanuric acid and ethylene carbonate results in the formation of polyetherols. The kinetic and mechanistic studies revealed that the initial step of the reaction is zero order related to ethylene carbonate. The rate‐limiting step is the decomposition of an intermediating dianion of ethylene dicarbonate into ethane‐1,2‐diolate dianion and carbon dioxide. Imide groups of isocyanuric acid inhibit the reaction. The mechanism of reaction was confirmed by spectroscopic methods. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 512–522, 2009
Suzuki Polycondensation: Polyarylenes à la Carte
Authors: Sakamoto Junji , Rehahn Matthias , Wegner Gerhard , Schlüter A. Dieter 
Published: May 2009

AbstractThis review draws a rather comprehensive picture of how Suzuki polycondensation was discovered in 1989 and how it was subsequently developed into the most powerful polymerization method for polyarylenes during the last 20 years. It combines insights into synthetic issues with classes of polymers prepared and touches upon aspects of this method's technological importance. Because a significant part of the developmental work was carried out in industry, the present review makes reference to an unusually large number of patents.magnified image
Preparation of Functional Poly(aroyltriazole)s by Metal‐Free Click Polymerization
Authors: Qin Anjun , Lam Jacky W. Y. , Jim Cathy K. W. , Tang Ben Zhong 
Published: May 2009

AbstractFunctional poly(aroyltriazoles) (PATAs) were synthesized by heating mixtures of bis(aroylacetylene)s and diazides in polar solvents such as DMF/toluene at a moderate temperature of 100 °C with high molecular weights (Mw up to 17 200) and regioregularities (1,4‐regioisomeric ratio up to ∼95%) in high yields (up to ∼95%). The obtained polymers are soluble in common organic solvents and are thermally stable. The PATAs containing triphenylamine units emit visible light and show unique solvatochromism, exhibiting large two‐photon absorption cross sections due to the intramolecular charge transfer between their electron‐donating triphenylamine and electron‐accepting aroyltriazole units. The tetraphenylethene (TPE)‐functionalized polymer shows intriguing aggregation‐induced emission phenomenon, that is, the polymer is weakly emissive in its solution state but emit strongly in its aggregate/solid state with quantum yield of ∼7.1%.
Structural determination of two new steroidal saponins from Smilax china
Authors: Huang Hui‐Lian , Liu Rong‐Hua , Shao Feng 
Published: May 2009

AbstractTwo new steroidal saponins (1 and 2) were isolated from the BuOH fraction of the 70% EtOH extract of the tubes of Smilax china, together with four known analogues, 3–6. The structures of the new compounds were elucidated by means of chemical evidence and spectroscopic analyses, including HR‐MS, IR, 1H‐ and 13C‐NMR, and 2D experiments (1H–1H COSY, HSQC and HMBC). Copyright © 2009 John Wiley & Sons, Ltd.
Including friction in the mathematics of classical plasticity
Authors: Chandler H. W. , Sands C. M. 
Published: May 2009

AbstractIn classical plasticity there are clear mathematical links between the dissipation function and the consequent yield function and flow rule. These links help to construct constitutive equations with the minimum of adjustable parameters. Modelling granular materials, however, requires that the dissipation function depends on the current stress state (frictional plasticity) and this changes the mathematical structure—altering the links and invalidating the associated flow rule. In this paper we show, for a large family of dissipation functions, how much of the structure remains intact when frictional dissipation is included. The surviving links are examined using straightforward physically based graphical insight and well‐established mathematical techniques leading to a central result, which provides a mathematical justification for the procedural features of hyperplasticity. This should allow hyperplasticity to be used more widely and certainly with increased confidence.As an example of the effectiveness of the general method, two specific dissipation functions are constructed from the simple physical concepts of sliding friction and granule damage. One is based on a Drucker–Prager cone and the other a Matsuoka–Nakai cone, both incorporate kinematic hardening and a compactive cap. In each Case a single smooth yield function with consistent flow rules is produced. The computational usefulness of an inequality derived in the paper is demonstrated in the generation of the figures showing yield surfaces and flow directions by means of a simple maximization procedure. Copyright © 2009 John Wiley & Sons, Ltd.
Time integration scheme for elastoplastic models based on anisotropic strain‐rate potentials
Authors: Rabahallah Meziane , Balan Tudor , Bouvier Salima , Teodosiu Cristian 
Published: May 2009

AbstractModelling of plastic anisotropy requires the definition of stress potentials (coinciding with the yield criteria in case of the associated flow rules) or, alternatively, plastic strain‐rate potentials. The latter approach has several advantages whenever material parameters are determined by means of texture measurements and crystal plasticity simulations. This paper deals with a phenomenological description of anisotropy in elastoplastic rate‐insensitive models by using strain‐rate potentials. A fully implicit time integration algorithm is developed in this framework and implemented in a static‐implicit finite element code. Algorithmic details are discussed, including the derivation of the consistent (algorithmic) tangent modulus and the numerical treatment of the yield condition. Typical sheet forming applications are simulated with the proposed implementation, using the recent non‐quadratic strain‐rate potential Srp2004‐18p. Numerical simulations are carried out for materials that exhibit strong plastic anisotropy. The numerical results confirm that the presented algorithm exhibits the same generality, robustness, accuracy, and time efficiency as state‐of‐the‐art yield criterion‐based algorithms. Copyright © 2009 John Wiley & Sons, Ltd.
Functionalization of Copper Surfaces by Plasma Treatments to Improve Adhesion of Epoxy Resins
Authors: Borges Juliano Nestor , Belmonte Thierry , Guillot Jérôme , Duday David , Moreno‐Couranjou Maryline , Choquet Patrick , Migeon Henri‐Noël 
Published: May 2009

AbstractAdhesion of epoxy resins on copper foils for printed circuit board (PCB) applications is improved by nearly a factor of 5, using surface cleaning and deposition of a 15‐nm‐thick film in a low‐pressure remote plasma‐enhanced chemical vapor deposition process. The cleaning pretreatment, using an N2–O2 oxidizing gas mixture with moderate heating (343 K), gives the best results. This pretreatment removes the carbonaceous contaminants present on the topmost surface of the sample and slightly oxidizes the copper into CuO. This oxide is then reduced during the deposition treatment, presumably by reaction with the aminopropyltrimethoxysilane (APTMS) precursor. The surface roughness is unchanged after treatment, thereby showing that the improvement of the copper/epoxy adhesion is only due to the chemistry of the plasma coating. Applying these results to dielectric barrier discharges allows us to achieve the same level of adhesion, which, therefore, does not depend on the process.
On Low Pressure Plasma Processing for Metal Protection
Authors: Palumbo Fabio , d'Agostino Riccardo , Fracassi Francesco , Laera Stefania , Milella Antonella , Angelini Emma , Grassini Sabrina 
Published: May 2009

AbstractDifferent processing issues dealing with plasma treatments for corrosion protection of metals are discussed. It is shown that plasma‐deposited inorganic coatings cannot be enough to ensure optimum protection to metal degradation. In particular, designing a suitable plasma pre‐treatment of the metal surface with the right feed gas can enhance the coating performance. The improvement due to pulsed mode deposition and hydrophobic layer coating are also discussed, leading both to one order magnitude increase in the charge transfer resistance with respect to continuous plasma deposited SiOx.
Sputter Deposition of Strain Gauges Using ITO/Ag
Authors: Gerdes Holger , Bandorf Ralf , Heckmann Ulrike , Schmidt Volker , Kricheldorf Hans‐Ulrich , Bräuer Günter 
Published: May 2009

AbstractIn many industrial applications strain gauges are commonly used for measurements of applied forces or the loading status of work pieces. While commercial strain gauges using polyimide foils can cause errors due to influence of humidity, directly applied thin film strain gauges avoid this problems. Besides the improvement of the signal due to avoiding glue and polymer substrate, that can creep and swell, also the gauge factor can be further improved by using new sensor materials. Indium tin oxide (ITO) is a very promising material especially for high temperature application. This paper presents investigations of Ag doped ITO films. The sheet resistance of the films increased first with increase in the silver content up to 20 at.‐%. Further increase in silver led to a decrease in the sheet resistance reaching less than 10 Ω for more than 75 at.‐% silver content of the resulting films. The gauge factor showed a maximum of 6.5 at 20 at.‐% Ag content, while the temperature coefficient of resistance (TCR) showed zero crossing for approximately 40 at.‐% Ag content.