bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transforming growth factor β1 mediates apoptotic activity of angiotensin II type I receptor blocker on prostate epithelium in vitro
Authors: Zhao Yayuan , Peng Jing , Zheng Lanbin , Yu Wei , Jin Jie 
Published: February 2010

AbstractBACKGROUNDThe significant association of benign prostatic hyperplasia (BPH) and hypertension indicates a common pathophysiological factor for both diseases. Hyperactivity of the renin‐angiotensin system (RAS) has been reported in BPH. Angiotensin II type I (AT1) receptor is the principal mediator of the RAS, and the antagonist, AT1 receptor blocker (ARB), can induce apoptosis in prostate epithelium cells and increase transforming growth factor β1 (TGF‐β1) expression. We aimed to investigate the mechanism of inhibition of AT1 receptor in prostate epithelium cells and the role of TGF‐β1.METHODSHuman prostate epithelium cell lines were treated with different concentrations of ARB (losartan) (0, 0.1, 1, 10, 100, and 1,000 µM) for 24–72 hr. Cell proliferation was analyzed by cell proliferation assay. The location of AT1 receptor was shown by immunocytohistochemistry and immunocytofluorescence study. Analysis of apoptosis was by use of terminal transferase TdT‐mediated dUTP‐biotin end labeling (TUNEL) and caspase 3/7 activity assay. Mitochondrial outer‐membrane permeabilization was measured by JC‐1 staining. The level of TGF‐β1 was determined by enzyme‐linked immunosorbent assay.RESULTSImmunohistochemistry and immunofluorescence analysis showed AT1 receptor expressed in epithelium cells. Compared to control cultures, cultures treated with losartan for 24–72 hr showed a dose‐dependent significant decrease in cell number, with apoptosis increased by 65.2%. Decreased cell number was reversed on treatment with anti‐TGF‐β1 antibody. TUNEL staining showed increased apoptosis in prostate epithelium cells exposed to losartan. Caspase 3/7 activation was increased and mitochondrial membrane potential was downregulated. Expression of TGF‐β1 in cells treated with losartan was higher than that in untreated cells.CONCLUSIONSThe apoptotic effect of blockade of AT1 receptor on human prostatic epithelium cells may be mediated through an autocrine the production of TGF‐β1. Furthermore, this finding may have implications for medication options. Prostate 70: 899–905, 2010. © 2010 Wiley‐Liss, Inc.
Hidden structure in amorphous solids
Authors: Inam F. , Lewis James P. , Drabold D. A. 
Published: February 2010

AbstractRecent theoretical studies of amorphous silicon (a‐Si) [Pan et al., Phys. Rev. Lett. 100, 206403 (2008)] have revealed subtle but significant structural correlations in network topology: the tendency for short (long) bonds to be spatially correlated with other short (long) bonds). These structures were linked to the electronic band tails in the optical gap. In this paper, we further examine these issues for a‐Si, and demonstrate that analogous correlations exist in amorphous SiO2, and in the organic molecule, β‐carotene. We conclude with a discussion of the origin of the effects and its possible generality.
Low temperature deposition of microcrystalline silicon germanium Si1‐xGex by RF‐PECVD
Authors: Fedala Abdelkrim , Simon Claude , Coulon Nathalie , Mohammed‐Brahim Tayeb , Abdeslam Mehena , Chami Ahmed‐Chafik 
Published: February 2010

AbstractHighly crystallized Si1‐xGex films with x<0.2 are obtained at low temperature, 165 °C, using conventional capacitively coupled RF PECVD reactor. This result is obtained thanks to adding argon to the usual hydrogen, silane and germane gas mixture. Without argon, germanium has the effect to block the crystallization. Present crystallized SiGe films will be used as active layer of low temperature processed transistors on plastics to improve the field effect mobility. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication of nanogaps with modified morphology by potential‐controlled gold deposition
Authors: Yi Zhiwei , Banzet Marko , Offenhäusser Andreas , Mayer Dirk 
Published: February 2010

AbstractNanogaps consisting of facing nanoelectrodes are used to contact nanoscale objects between the nanoelectrodes and to measure charge transport properties through them. Here, nanogaps were fabricated by gold electrodeposition and the surface morphology was modified by the electrochemical potential, creating nanogaps with rounded surface at high overpotentials and needle‐like surface at low overpotentials. Quantized conductance was observed when the nanogap was narrowed until it was bridged by a few atoms. The needle‐like nanogaps showed a smaller contact area and better stability than the rounded nanogaps. The needle‐like nanogaps have the potential to electrically address an individual nanoscale object. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Metabolism of the major Echinacea alkylamideN‐isobutyldodeca‐2E,4E,8Z,10Z‐tetraenamide by human recombinant cytochrome P450 enzymes and human liver microsomes
Authors: Toselli F. , Matthias A. , Bone K.M. , Gillam E.M.J. , Lehmann R.P. 
Published: February 2010

AbstractEchinacea preparations are used for the treatment and prevention of upper respiratory tract infections. The phytochemicals believed responsible for the immunomodulatory properties are the alkylamides found in ethanolic extracts, with one of the most abundant being theN‐isobutyldodeca‐2E,4E,8Z,10Z‐tetraenamide (1). In this study, we evaluated the human cytochrome P450 enzymes involved in the metabolism of this alkylamide using recombinant P450s, human liver microsomes and pure synthetic compound. Epoxidation,N‐dealkylation and hydroxylation products were detected, with different relative amounts produced by recombinant P450s and microsomes. The major forms showing activity toward the metabolism of 1 were CYP1A1, CYP1A2 (both producing the same epoxide andN‐dealkylation product), CYP2A13 (producing two epoxides), and CYP2D6 (producing two epoxides and an hydroxylated metabolite). Several other forms showed less activity. In incubations with human liver microsomes and selective inhibitors, CYP2E1 was found to be principally responsible for producing the dominant, hydroxylation product, whereas CYP2C9 was the principal source of the epoxides and CYP1A2 was responsible for the dealkylation product. In summary, in this study the relative impacts of the main human xenobiotic‐metabolizing cytochrome P450s on the metabolism of a major Echinacea alkylamide have been established and the metabolites formed have been identified. Copyright © 2010 John Wiley & Sons, Ltd.
Dynamic study of stacked packaging units by operational modal analysis
Authors: Bernad Carlos , Laspalas Alberto , González David , Liarte Elías , Jiménez Miguel A. 
Published: February 2010

AbstractLaboratory simulation of transport vibration has been the object of many studies in recent years due to the financial implications of potential customer claims in respect of damage caused during product distribution and the need for tools for packaging optimization. Most of these works concentrate on the special nature of transport vibrations and how to reproduce them: Power Spectral Density (PSD) profiles related to road and truck characteristics, the non‐stationary aspects of the environment, the non‐Gaussian characteristics of the recorded vibrations and the best procedures for meaningful laboratory testing.In the present work, a different point of view is applied to the issue. The paper deals with the dynamics of different corrugated stacked packaging units by means of operational modal analysis and a 6 degrees of freedom multi‐axis shaker table.The results show the already known non‐linear behaviour of the paperboard containers and the natural frequencies and modes likely to appear in the packaging. The relevance of bending‐like modes in relation to laboratory testing is discussed. Copyright © 2010 John Wiley & Sons, Ltd.
A computational approach to stability of polytopic families of quasi‐polynomials with single delay
Authors: Tuzcu İlhan 
Published: February 2010

AbstractThis paper addresses stability of families of linear, time‐invariant systems with single time delay. The families are generated by system parameters uncertain within known intervals, and appearing linearly (affinely) in the systems' characteristic functions, which are quasi‐polynomials. First, easily implementable conditions for delay‐independent stability for such families are given. Later, for families that fail to be stable independently of delay, a computationally tractable method is presented to compute all possible time‐delay intervals for which the families are stable. The method is based on the edge theorem and provides the complete stability picture of a given family. Numerical examples illustrate the application of the method. Copyright © 2010 John Wiley & Sons, Ltd.
Deterministic random walks on regular trees
Authors: Cooper Joshua , Doerr Benjamin , Friedrich Tobias , Spencer Joel 
Published: February 2010

AbstractJim Propp's rotor–router model is a deterministic analog of a random walk on a graph. Instead of distributing chips randomly, each vertex serves its neighbors in a fixed order.Cooper and Spencer (Comb Probab Comput 15 (2006) 815–822) show a remarkable similarity of both models. If an (almost) arbitrary population of chips is placed on the vertices of a grid ℤd and does a simultaneous walk in the Propp model, then at all times and on each vertex, the number of chips on this vertex deviates from the expected number the random walk would have gotten there by at most a constant. This constant is independent of the starting configuration and the order in which each vertex serves its neighbors.This result raises the question if all graphs do have this property. With quite some effort, we are now able to answer this question negatively. For the graph being an infinite k‐ary tree (k ≥ 3), we show that for any deviation D there is an initial configuration of chips such that after running the Propp model for a certain time there is a vertex with at least D more chips than expected in the random walk model. However, to achieve a deviation of D it is necessary that at least exp(Ω(D2)) vertices contribute by being occupied by a number of chips not divisible by k at a certain time. © 2010 Wiley Periodicals, Inc. Random Struct. Alg., 2010
The CLEHES‐MOOD: An enactive technology towards effective and collaborative action
Authors: García De La Cerda Osvaldo , Laulié Cerda Lyonel 
Published: February 2010

AbstractThe present paper shows the creation of an enactive technology of self‐observation that facilitates the search of effective and collaborative action strategies for any observer that belongs to an organization or human activity system, with the experience of the user as the cornerstone of design. The technology is based in the observation of moods using the ontological tool CLEHES© for opening different distinctions, re‐configures microidentities and enhance awareness. For that, the technology was proved in a sample of executives and administrative personnel whom described their own experiences and learnings by the use of the CLEHES‐MOOD. Copyright © 2010 John Wiley & Sons, Ltd.
A four‐dimensional view of IT business value
Authors: Cao Guangming 
Published: February 2010

AbstractResearch on IT business value has recognized that organizational factors play critical roles in affecting how IT impacts on firm performance. However, there is neither a coherent way of specifying organizational factors nor a consensus on the relationship between IT and organizational factors within the research domain. This paper reviews IT business value literature and classifies organizational factors identified in the literature into four categories, based on a four‐dimensional view of organizations. A main finding is that pairwise relationships between IT and one single organizational factor have often been the basis for understanding IT business value, while the notion of how IT business value is affected by the interaction between IT and key organizational factors simultaneously is yet to be fully understood and empirically examined. As a result, this paper proposes a holistic approach to understanding IT business value and presents a discussion about future IT business research. Copyright © 2010 John Wiley & Sons, Ltd.
Differentiation and Characterization of Metabolically Functioning Hepatocytes from Human Embryonic Stem Cells
Authors: Duan Yuyou , Ma Xiaochui , Zou Wei , Wang Charles , Bahbahan Iman Saramipoor , Ahuja Tijess P. , Tolstikov Vladimir , Zern Mark A. 
Published: February 2010

AbstractHuman embryonic stem cells (hESCs) may provide a cell source for functional hepatocytes for clinical applications and drug development. Initially, the hESC population was enriched to be more than 85% definitive endoderm (DE) as assessed by the expression of CXCR4, SOX17, and FOXA2. We then successfully converted DE into hepatic progenitors with 93% of the cells being positive for α-feto protein within 9 days. The percentage of albumin positive cells gradually increased to 90% at days 20-22 after differentiation. Moreover, our hESC-derived hepatocytes (hEH) developed a complete biotransformation system including phase I and II metabolizing enyzmes and phase III transporters. Nuclear receptors, which are critical in regulating the expression of metabolizing enzymes, were also expressed by our hEH. Using ultraperformance liquid chromatography-tandem mass spectrometry technology, we identified seven metabolic pathways of the drug bufuralol including four newly-reported ones in our hEH, which are the same as those in freshly isolated human primary hepatocytes (hPH). In addition, the results of the metabolism of four drugs indicate that our hEH have the capacity to metabolize these drugs at levels that are comparable to hPH. In conclusion, we have generated a relatively homogenous population of hepatocytes from hESCs, which appear to have complete metabolic function that is comparable to primary liver cells. These results represent a significant step towards the efficient differentiation of mature hepatocytes for cell-based therapeutics as well as for pharmacology and toxicology studies.
Hypoxia Influences the Vascular Expansion and Differentiation of Embryonic Stem Cell Cultures Through the Temporal Expression of Vascular Endothelial Growth Factor Receptors in an ARNT-Dependent Manner
Authors: Han Yu , Kuang Shu-Zhen , Gomer Alla , Ramirez-Bergeron Diana L. 
Published: February 2010

Abstract
Adaptive responses to low oxygen (O2) tension (hypoxia) are mediated by the heterodimeric transcription factor hypoxia inducible factor (HIF). When stabilized by hypoxia, bHLH-PAS α- and β- (HIF-1β or ARNT) HIF complex regulate the expression of multiple genes, including vascular endothelial growth factor (VEGF). To investigate the mechanism(s) through which hypoxia contributes to blood vessel development, we used embryonic stem cell (ESC) differentiation cultures that develop into embryoid bodies (EBs) mimicking early embryonic development. Significantly, low O2 levels promote vascular development and maturation in wild-type (WT) ESC cultures measured by an increase in the numbers of CD31+ endothelial cells (ECs) and sprouting angiogenic EBs, but refractory in Arnt−/− and Vegf−/− ESC cultures. Thus, we propose that hypoxia promotes the production of ECs and contributes to the development and maturation of vessels. Our findings further demonstrate that hypoxia alters the temporal expression of VEGF receptors Flk-1 (VEGFR-2) and the membrane and soluble forms of the antagonistic receptor Flt-1 (VEGFR-1). Moreover, these receptors are distinctly expressed in differentiating Arnt−/− and Vegf−/− EBs. These results support existing models in which VEGF signaling is tightly regulated during specific biologic events, but also provide important novel evidence that, in response to physiologic hypoxia, HIF mediates a distinct stoichiometric pattern of VEGF receptors throughout EB differentiation analogous to the formation of vascular networks during embryogenesis.
Isolation of a Highly Myogenic CD34-Negative Subset of Human Skeletal Muscle Cells Free of Adipogenic Potential
Authors: Pisani Didier F. , Dechesne Claude A. , Sacconi Sabrina , Delplace Severine , Belmonte Nathalie , Cochet Olivia , Clement Noémie , Wdziekonski Brigitte , Villageois Albert P. , Butori Catherine , Bagnis Claude , Di Santo James P. , Kurzenne Jean-Yves , Desnuelle Claude , Dani Christian 
Published: February 2010

AbstractThe differentiation of multipotent cells into undesirable lineages is a significant risk factor when performing cell therapy. In muscular diseases, myofiber loss can be associated with progressive fat accumulation that is one of the primary factors leading to decline of muscular strength. Therefore, to avoid any contribution of injected multipotent cells to fat deposition, we have searched for a highly myogenic but nonadipogenic muscle-derived cell population. We show that the myogenic marker CD56, which is the gold standard for myoblast-based therapy, was unable to separate muscle cells into myogenic and adipogenic fractions. Conversely, using the stem cell marker CD34, we were able to sort two distinct populations, CD34+ and CD34−, which have been thoroughly characterized in vitro and in vivo using an immunodeficient Rag2−/−γc−/− mouse model of muscle regeneration with or without adipose deposition. Our results demonstrate that both populations have equivalent capacities for in vitro amplification. The CD34+ cells and CD34− cells exhibit equivalent myogenic potential, but only the CD34− population fails to differentiate into adipocytes in vitro and in vivo after transplantation into regenerative fat muscle. These data indicate that the muscle-derived cells constitute a heterogeneous population of cells with various differentiation potentials. The simple CD34 sorting allows isolation of myogenic cells with no adipogenic potential and therefore could be of high interest for cell therapy when fat is accumulated in diseased muscle.
An efficient anycast scheme for discoveringkservices in cluster‐based mobilead hocnetworks
Authors: Dow C. R. , Lin P. J. , Chen S. C. , Hwang S. F. 
Published: February 2010

AbstractAnycast is a one‐to‐any bidirectional transmission scheme that can be used to provide various service‐oriented applications. However, traditional anycast cannot support some distributed applications that need to locate multiple servers such as network time protocols and threshold cryptography. Although there are some extended anycast schemes that can support the discovery ofkservices, they may cause high control overhead, low satisfaction ratio, or high searching latency when there are more service requesters and providers. The main reasons for these shortcomings are unknown service information and limited hierarchical structure. This work proposes an efficient anycast scheme, called AnyKast, for discoveringkservices in cluster‐based mobilead hocnetworks. In the AnyKast scheme, an anycast tree based on the clustering and virtual backbone is established to reduce unnecessary message transmission. In the anycast tree, anycast clusterheads disseminate their information to certain specific nodes that take the service information and perform the service selection task instead of blindly searching. Furthermore, to decrease the cost of service information collection and maintenance, scope flooding is used to limit the information transmission, and information piggybacking and periodical inquiry mechanism are used to increase the service information accuracy. The experimental results demonstrate that our scheme can effectively discover services, reduce request and reply message control overhead, and lower the searching latency. Copyright © 2010 John Wiley & Sons, Ltd.
APOBEC‐1‐mediated RNA editing
Authors: Blanc Valerie , Davidson Nicholas O. 
Published: February 2010

AbstractRNA editing defines a molecular process by which a nucleotide sequence is modified in the RNA transcript and results in an amino acid change in the recoded message from that specified in the gene. We will restrict our attention to the type of RNA editing peculiar to mammals, i.e., nuclear C to U RNA editing. This category of RNA editing contrasts with RNA modifications described in plants, i.e., organellar RNA editing (reviewed in Ref 1). Mammalian RNA editing is genetically and biochemically classified into two groups, namely insertion‐deletional and substitutional.2 Substitutional RNA editing is exclusive to mammals, again with two types reported, namely adenosine to inosine and cytosine to uracil (C to U).3, 4 This review will examine mammalian C to U RNA editing of apolipoproteinB (apoB) RNA and the role of the catalytic deaminase Apobec‐1.5, 6 We will speculate on the functions of Apobec‐1 beyond C to U RNA editing as implied from its ability to bind AU‐rich RNAs and discuss evidence that dysregulation of Apobec‐1 expression might be associated with carcinogenesis through aberrant RNA editing or altered RNA stability. Copyright © 2010 John Wiley & Sons, Inc.This article is categorized under:

Biological Mechanisms > Regulatory Biology
Simultaneous/Incidental Cholecystectomy During Gastric/Esophageal Resection: Systematic Analysis of Risks and Benefits
Authors: Gillen Sonja , Michalski Christoph W. , Schuster Tibor , Feith Marcus , Friess Helmut , Kleeff Jörg 
Published: February 2010

AbstractBackgroundAfter esophageal/gastric resection with resulting truncal vagotomy, the incidence of gallstone formation seems to increase. The clinical relevance of gallstones and the role of simultaneous/incidental cholecystectomy in this setting are controversially discussed.MethodsSystematic analysis has been performed for retrospective/prospective studies on the incidence/symptoms of gallstone formation after esophageal/gastric resection. Pooled estimates of the incidence of cholecystectomies were calculated by random effect models. Risk analyses of simultaneous, acute postoperative cholecystectomy and long‐term cholecystectomy were performed.ResultsSixteen studies on gallstone formation after upper gastrointestinal (GI) surgery (3,735 patients) reported increased incidences of 5–60% with a pooled estimate of 17.5% (95% confidence interval (CI), 14.1–21.2%; inconsistency statistic (I2) = 86%) compared with 4–12% in the control population. In 113 of 3,011 patients (12 studies), late cholecystectomies were performed for symptomatic cholecystolithiasis, corresponding to an estimated overall proportion of 4.7% (95% CI, 2.1–8.2%; I2 = 92%). In 1.2% (95% CI, >0–3.7%; I2 = 93%) of patients undergoing upper GI surgery, a cholecystectomy was performed because of acute postoperative biliary problems (4 studies, 8,748 patients). Simultaneous cholecystectomy had a higher morbidity of 0.95% (95% CI, 0.54–1.49%; I2 = 28%) compared with the calculated additional morbidity of early and late cholecystectomy of 0.45%.ConclusionsApproximately 6% of patients undergoing upper GI surgery are expected to require cholecystectomy during follow‐up. Because late cholecystectomies can be performed safely and because the additional calculated morbidity for these operations is lower than the morbidity for simultaneous cholecystectomy, it cannot generally be recommended to remove a normal acalculous gallbladder during upper GI surgery.