bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluorophilic cobalt phthalocyanine‐containing Nafion membrane: high oxygen permeability and proton conductivity in the membrane
Authors: Shoji Masami , Nishide Hiroyuki 
Published: June 2009

AbstractA multiply‐fluorinated cobalt phthalocyanine (CoFPC) was prepared, which could reversibly interact with oxygen. CoFPC was introduced into the hydrophobic perfluoroethylene‐backbone domain of the Nafion membrane. The localization of CoFPC did not reduce the high proton conductivity (10−2–10−3 S cm−1) ascribed to the hydrophilic channel of Nafion. The oxygen permeability through the CoFPC/Nafion membrane was higher than the nitrogen permeability and that of the pristine Nafion membrane, and was significantly enhanced at the lower upstream pressure. The permselectivity of oxygen versus nitrogen increased beyond 20 with the CoFPC content in the membrane. The CoFPC/Nafion membrane was coated on a glassy carbon modified with a Pt/C catalyst. The high electrochemical reduction current of oxygen suggested that the CoFPC/Nafion membrane efficiently supplied oxygen to the Pt/C catalyst. Copyright © 2009 John Wiley & Sons, Ltd.
β1 integrin/FAK/ERK signalling pathway is essential for human fetal islet cell differentiation and survival
Authors: Saleem Saira , Li Jinming , Yee Siu‐Pok , Fellows George F , Goodyer Cynthia G , Wang Rennian 
Published: June 2009

Abstractβ1 integrin and collagen matrix interactions regulate the survival of cells by associating with focal adhesion kinase (FAK) and initiating MAPK/ERK signalling, but little is known about these signalling pathways during human fetal islet ontogeny. The purpose of this study was to investigate whether β1 integrin/FAK activation of the MAPK/ERK pathway regulates human fetal islet cell expression of endocrine cell markers and survival. Isolated human (18–21 weeks fetal age) islet–epithelial cell clusters, cultured on collagen I, were examined using β1 integrin blocking antibody, β1 integrin siRNA and FAK expression vector. Perturbing β1 integrin function in the human fetal islet–epithelial cell clusters resulted in a marked decrease in cell adhesion, in parallel with a reduction in the number of cells expressing PDX‐1, insulin and glucagon (p < 0.05). β1 integrin blockade disorganized focal adhesion contacts in the PDX‐1+ cells and decreased activation of FAK and ERK1/2 signalling in parallel with an increase in expression of cleaved caspases 9 and 3 (p < 0.01). Similar results were obtained following an siRNA knock‐down of β1 integrin expression. In contrast, over‐expression of FAK not only increased phospho‐ERK and the expression of PDX‐1, insulin and glucagon (p < 0.05) but also abrogated the decreases in phospho‐ERK and PDX‐1 by β1 integrin blockade. This study demonstrates that activation of the FAK/ERK signalling cascade by β1 integrin is involved in the differentiation and survival of human fetal pancreatic islet cells. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Up‐regulation of autophagy in small intestine Paneth cells in response to total‐body γ‐irradiation
Authors: Gorbunov Nikolai V. , Kiang Juliann G. 
Published: June 2009

AbstractMacroautophagy (mAG) is a lysosomal mechanism of degradation of cell self‐constituents damaged due to variety of stress factors, including ionizing irradiation. Activation of mAG requires expression of mAG protein Atg8 (LC3) and conversion of its form I (LC3‐I) to form II (LC3‐II), mediated by redox‐sensitive Atg4 protease. We have demonstrated upregulation of this pathway in the innate host defense Paneth cells of the small intestine (SI) due to ionizing irradiation and correlation of this effect with induction of pro‐oxidant inducible nitric oxide synthase (iNOS). CD2F1 mice were exposed to 9.25 Gy γ‐ionizing irradiation. Small intestinal specimens were collected during 7 days after ionizing irradiation. Assessment of ionizing irradiation‐associated alterations in small intestinal crypt and villus cells and activation of the mAG pathway was conducted using microscopical and biochemical techniques. Analysis of iNOS protein and the associated formation of nitrites and lipid peroxidation products was performed using immunoblotting and biochemical analysis, and revealed increases in iNOS protein, nitrate levels and oxidative stress at day 1 following ionizing irradiation. Increase in immunoreactivity of LC3 protein in the crypt cells was observed at day 7 following ionizing irradiation. This effect predominantly occurred in the CD15‐positive Paneth cells and was associated with accumulation of LC3‐II isoform. The formation of autophagosomes in Paneth cells was confirmed by transmission electron microscopy (TEM). Up‐regulation of LC3 pathway in the irradiated SI was accompanied by a decreased protein–protein interaction between LC3 and chaperone heat shock protein 70. A high‐level of LC3‐immunoreactivity in vacuole‐shaped structures was spatially co‐localized with immunoreactivity of 3‐nitro‐tyrosine. The observed effects were diminished in iNOS knockout B6.129P2‐NOS2tm1Lau/J mice subjected to the same treatments. We postulate that the observed up‐regulation of mAG in the irradiated small intestine is at least in part mediated by the iNOS signalling mechanism. Published in 2009 by John Wiley & Sons, Ltd.
Adamalysins in biology and disease
Authors: van Goor Harry , Melenhorst Wynand BWH , Turner Anthony J , Holgate Stephen T 
Published: June 2009

AbstractADAMs (a disintegrin and metalloprotease) are membrane‐bound enzymes, capable of shedding a multitude of proteins from the surface of the cell. They are therefore considered crucial modulators of physiological and pathophysiological processes. The structure and function of ADAMs is related to those of a family of snake venom metalloproteases which also possess a potential adhesion domain as well as a potential protease domain. Mammalian ADAMs are involved in various biological and disease‐related processes, such as cell–cell fusion, adhesion and intracellular signalling. Functional involvement has been described in sperm–egg binding and fusion, trophoblast invasion and matrix degradation during pregnancy, angiogenesis and neovascularization. Clinically, ADAMs are implicated in pathological processes, including cancer, inflammation, neurodegeneration and fibrosis, through shedding of the apoptosis‐inducing FAS ligand, cytokines and growth factors. A second group of proteins within the ADAM family has recently been discovered. These contain several thrombospondin‐like repeats in their C‐terminal regions, in the absence of the transmembrane domain known to be present in ADAMs. These proteins were called the ADAMTS (ADAM with thrombospondin domains) family. The relevance of ADAMTS enzymes has become evident in patients with a deficiency in ADAMTS‐13, a von Willebrand factor cleaving protease. These patients develop thrombotic thrombocytopenic purpura, a devastating thrombotic disorder caused by widespread microvascular thrombi composed of platelets and von Willebrand factor (VWF). Here we focus on the genetic, developmental, functional and disease‐related aspects of ADAMs and ADAMTS. Finally we discuss the perspectives of the therapeutical potential of ADAMs in disease. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Over‐expression of AEG‐1 significantly associates with tumour aggressiveness and poor prognosis in human non‐small cell lung cancer
Authors: Song Libing , Li Wen , Zhang Huizhong , Liao Wenting , Dai Ting , Yu Chunping , Ding Xiaofan , Zhang Lanjun , Li Jun 
Published: June 2009

AbstractAstrocyte elevated gene 1 (AEG‐1), a novel oncoprotein, has been implicated in oncogenesis and cancer progression in various types of human cancers. The clinical significance and biological role of AEG‐1 in non‐small cell lung cancer (NSCLC), however, remain unclear. In the present study, we found that the expression of AEG‐1 was markedly up‐regulated in NSCLC cell lines and NSCLC tissues at the level of both transcription and translation. Ectopically expressed AEG‐1 enhanced the migratory and invasive abilities of NSCLC cells, whereas knockdown of endogenous AEG‐1 by specific shRNAs significantly inhibited these abilities. The function of AEG‐1 on metastasis modulation was associated with the activation of the PI3K–Akt and NF‐κB signalling pathways. Furthermore, we showed high expression of AEG‐1 in 99/200 (49.5%) paraffin‐embedded archival NSCLC specimens. Moreover, statistical analysis displayed a significant correlation in AEG‐1 expression with the clinical stage (p < 0.001), T classification (p = 0.001), N classification (p = 0.015), distant metastasis (p = 0.004) and differentiation (p = 0.027). Patients with higher AEG‐1 expression had an overall shorter survival time, whereas patients with lower expression of AEG‐1 had a better survival time. Multivariate analysis suggested that AEG‐1 expression might be an independent prognostic indicator for the survival of NSCLC patients. Taken together, our results suggest that elevated expression of AEG‐1 plays an important role in the aggressiveness of NSCLC, leading to a poor clinical outcome. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
ADAM12s as a first‐trimester screening marker of trisomy
Authors: Wortelboer E. J. , Linskens I. H. , Koster M. P. H. , Stoutenbeek P. , Cuckle H. , Blankenstein M. A. , Visser G. H. A. , van Vugt J. M. G. , Schielen P. C. J. I. 
Published: June 2009

AbstractObjectiveTo evaluate the potential of maternal serum A Disintegrin And Metalloprotease 12‐S (ADAM12s) as an additional marker for the combined test in the Dutch first‐trimester national Down syndrome (DS) screening program.MethodsSerum samples were collected between 2004 and 2007 as part of the national program. A total of 218 singleton cases of trisomy 21 (DS), 62 trisomy 18 (Edwards syndrome) and 29 trisomy 13 (Patau syndrome) were identified. All cases were matched with controls for gestation, maternal weight and maternal age. The serum concentration of ADAM12s was determined ‘blind’ to outcome and expressed in multiples of the gestation‐specific median for controls (MoM).ResultsThe median ADAM12s was 1.00 MoM in controls and in the DS cases at 8, 9, 10, 11, 12, 13 weeks it was 0.45 (n = 3), 0.73 (22), 0.74 (53), 0.85 (37), 0.92 (71), 1.06 (32) MoM, respectively. The median for trisomy 18 was 0.85 MoM and for trisomy 13 0.63 MoM.ConclusionThe ADAM12s MoM values were clearly reduced in early first‐trimester for all trisomies. However, the screening performance for DS did not greatly improve adding ADAM12s. ADAM12s could be an additional biochemical marker for first‐trimester screening for trisomies other than DS. Copyright © 2009 John Wiley & Sons, Ltd.
Risk calculation of developing type 2 diabetes in Libyan adults
Authors: Abduelkarem AR , Sharif SI , Hammrouni AM , Aldouibi SS , Albraiki WM , El‐Shareif HJ 
Published: June 2009

AbstractThe aim of this study was to identify nationals at risk of developing type 2 diabetes within the next 10 years in some areas across Tripoli Health Authority in Libya.In this questionnaire‐based survey, a total of 400 Libyan nationals of both genders were randomly selected from seven areas across the central area of Tripoli Health Authority (Soug El‐Juma, Zawet Dahmani, Al‐Furnaj, Ain Zara, Al‐Madena Centre, Al‐Dhahra Centre, and Noflean).All participants approached (400) completed the study and responded to the items of the survey. Based on a modified Finnish Type 2 Diabetes Risk Score test (FINDRISC), 129 (32.3%) were categorised as either at moderate or at high/very high risk of developing diabetes within the next 10 years of life. Among the 129 participants at risk, body mass index was >25 kg/m2 in 125 (96.9%) and waist circumferences were high (>88 cm for females;>102 cm for males) in almost 45% of the women and 22% of the men.We found that in the sample studied the risk of developing diabetes was clear, and there is no doubt that interventions to reduce such risk are a priority rather than a need. Diabetes has a great impact on the health of the nation and also on the future resources of the country in managing the disease and its complications; a health education/health campaign could be one good answer to tackle the problem. Copyright ©2009 John Wiley & Sons.
A novel, spontaneously immortalized, human prostate cancer cell line, Bob, offers a unique model for pre‐clinical prostate cancer studies
Authors: Attard Gerhardt , Rizzo Sian , Ledaki Ioanna , Clark Jeremy , Reid Alison H.M. , Thompson Alan , Khoo Vincent , de Bono Johann S. , Cooper Colin S. , Hudson David L. 
Published: June 2009

AbstractINTRODUCTIONNew in vitro models of castration‐resistant prostate cancer (CRPC) are urgently required.METHODSTrans‐rectal needle biopsies (TRBP) of the prostate were performed for research purposes on progressing CRPC patients who had not received prior treatment to the prostate. Biopsies were immediately digested with collagenase and plated onto collagen‐coated flasks with a feeder layer of 3T6 cells and cultured in cytokine‐supplemented keratinocyte serum‐free medium.RESULTSBiopsies from 25 patients were collected and one of these, following an initial period of crisis, spontaneously immortalized. A series of cell lines called Bob were then established from a clone that survived CD133‐selection followed by 4 weeks under adhesion‐independent conditions in methylcellulose. Gains and losses previously described in clinical prostate tumors, most notably loss of 8(p) and gain of 8(q), were identified on comparative genomic hybridization and long‐term growth in culture, survival in methylcellulose and invasion through matrigel confirmed the malignant phenotype of Bob. Furthermore, Bob expressed high levels of p53 and markers of early differentiation, including K8, prostatic acid phosphatase and prostate stem cell antigen. There was, however, no in vivo growth and ERG and ETV1 were not rearranged. Growth in serum permitted some differentiation.CONCLUSIONThis is the first spontaneously immortalized prostate cancer cell line to be established from a TRBP of a patient with CRPC. Bob is a novel pre‐clinical model for functional studies in CRPC and especially for studying the CRPC “basal” phenotype. Prostate 69: 1507–1520, 2009. © 2009 Wiley‐Liss, Inc.
The use of automatic tools and human expertise in template‐based modeling of CASP8 target proteins
Authors: Venclovas Česlovas , Margelevičius Mindaugas 
Published: June 2009

AbstractHere, we describe our template‐based protein modeling approach and its performance during the eighth community‐wide experiment on the Critical Assessment of Techniques for Protein Structure Prediction (CASP8, http://predictioncenter.org/casp8). In CASP8, our modeling approach was supplemented by the newly developed distant homology detection method based on sequence profile–profile comparison. Detection of structural homologs that could be used as modeling templates was largely achieved by automated profile‐based searches. However, the other two major steps in template‐based modeling (TBM) (selection of the best template(s) and construction of the optimal sequence‐structure alignment) to a large degree relied on the combination of automatic tools and manual input. The analysis of 64 domains categorized by CASP8 assessors as TBM domains revealed that we missed correct structural templates for only four of them. The use of multiple templates or their fragments enabled us to improve over the structure of the single best PDB template in about 1/3 of our models for TBM domains. Our results for sequence‐structure alignments are mixed. Although many models have optimal or near optimal sequence mapping, a large fraction contains one or more misaligned regions. Strikingly, in spite of this, our TBM models have the best overall alignment accuracy scores. This clearly suggests that the correct mapping of protein sequence onto three‐dimensional structure remains one of the big challenges in protein structure prediction. Proteins 2009. © 2009 Wiley‐Liss, Inc.
X‐ray characterization of epi‐Ge/Pr2O3/Si(111) layer stacks by pole figures and reciprocal space mapping
Authors: Zaumseil Peter , Giussani Alessandro , Rodenbach Peter , Schroeder Thomas 
Published: June 2009

AbstractAn epi‐Ge/Pr2O3/Si(111) layer structure prepared by consecutive steps of epitaxial deposition and annealing is used to demonstrate the possibility of a complex characterization by combination of different X‐ray diffraction techniques. Especially pole figure measurements, reciprocal space mapping (RSM) and high resolution (HR) Θ/2Θ scans at selected inclined netplanes were successfully used to determine the in‐plane lattice orientation of the layers relative to the substrate, the strain state of all layers and the structural perfection of the epi‐Ge film. It was found that the major part of the epi‐Ge layer has the same type A stacking orientation as the Si substrate, but about 0.6% is of type B. The Pr2O3 buffer layer exhibits type B only. The strain state of oxide and epi‐Ge was determined, and a small difference in the lattice constant of type A and B epi‐Ge was found. Microtwins lying in inclined {111} planes were unambiguously identified by pole figure measurements as the dominating structural defects in the epi‐Ge layer. They cause a characteristic scattering pattern in reciprocal space maps. The proposed combination of X‐ray techniques allows a relatively fast, integral and non‐destructive analysis of heteroepitaxial semiconductor oxide semiconductor structures.
Heteroepitaxial growth of lattice matched films on GaAs(001)
Authors: Jenichen B. , Kaganer V. M. , Shayduk R. , Braun W. , Trampert A. 
Published: June 2009

AbstractThe thin films of lattice matched materials Fe3Si and Ge are grown on GaAs(001) by molecular beam epitaxy and studied by grazing incidence X‐ray diffraction. In the initial phase of Fe3Si growth, the surface is rough due to a formation of small islands. Two‐dimensional layer‐by‐layer growth arises later on. Germanium grows on GaAs in a layer‐by‐layer growth mode right from the beginning. A substantial improvement of the surface smoothness of the Ge film during the growth is found.
Interfacial roughness of Fe3Si/GaAs(001) films studied by X‐ray crystal truncation rods
Authors: Kaganer Vladimir , Jenichen Bernd , Shayduk Roman , Braun Wolfgang 
Published: June 2009

AbstractCrystal truncation rods (CTRs) from thin Fe3Si films grown on GaAs(001) by molecular beam epitaxy (MBE) are measured at different stages of deposition. The films do not develop their own surface roughness but are conformal to the substrate, so that the substrate roughness governs the whole system. A factor that describes the roughness of a zinc blende structure in the β model of terrace height probabilities is derived and applied to describe the experimental curves. We show that the β model adequately describes the CTRs while the model of continuous Gaussian fluctuations of the surface height notably underestimates the root‐mean‐squared (rms) roughness.
Ripple structures on surfaces and underlying crystalline layers in ion beam irradiated Si wafers
Authors: Grenzer J. , Biermanns A. , Mücklich A. , Grigorian S. A. , Pietsch U. 
Published: June 2009

AbstractWe report on the formation of ion beam induced ripples in Si(001) wafers when bombarded with Ar+ ions at an energy of 60 keV. A set of samples varying incidence and azimuthal angles of the ion beam with respect to the crystalline surface orientation was studied by two complementary near surface sensitive techniques, namely atomic force microscopy and depth‐resolved X‐ray grazing incidence diffraction (GID). Additionally, cross‐section TEM investigations were carried out. The ripple‐like structures are formed at the sample surface as well as at the buried amorphous–crystalline interface. Best quality of the ripple pattern was found when the irradiating ion beam was aligned parallel to the (111) planes. The quality decreases rapidly if the direction of the ion beam deviates from (111).
Structural changes in Si crystals exposed to chemical etching and ion implantation
Authors: Fodchuk I. , Zaplitnyy R. , Kazemirskiy T. , Litvinchuk I. , Swiatek Z. 
Published: June 2009

AbstractResults of X‐ray diffraction studies on structural changes in Si crystals caused by chemical etching for 40 s in HF, HNO3 solution and phosphorus‐ion implantation with the energy E = 100 keV and dose D = 8 × 1014 cm−2 are represented.Two‐ and three‐crystal X‐ray diffractometry methods are used for a quantitative assessment of structural changes occurring in the near‐surface crystal layers. Analysis of experimental rocking curves was made with the use of different approaches developed on the basis of kinematic and dynamic theory of X‐ray scattering in the imperfect crystals. A model of possible system of structural defects in the near‐surface silicon layers modified by chemical etching and ion implantation is proposed. The model accounts for the availability of respective sizes and concentrations of spherical and disc‐shaped cluster formations, dislocation loops.
Three‐dimensional ordering in self‐organized (In,Ga)As quantum dot multilayer structures
Authors: Kladko V. , Slobodian M. , Lytvyn P. , Strelchuk V. , Mazur Yu. , Marega E. , Hussein M. , Salamo G. 
Published: June 2009

AbstractMolecular beam epitaxy (MBE) grown In0.5Ga0.5As/GaAs multilayer structures with quantum dots chains (QDs), obtained under different growth conditions, were investigated by high‐resolution X‐ray diffractometry (HRXRD) and AFM. It was determined that self‐organized epitaxial growth of In0.5Ga0.5As/GaAs can lead to the formation of three‐dimensional quantum‐dot crystals with triclinic (distorted cubic) unit cell. The mechanisms of QDs ordering in dependence on As flux are analyzed.
Spatially resolved strain within a single SiGe island investigated by X‐ray scanning microdiffraction
Authors: Diaz Ana , Mocuta Cristian , Stangl Julian , Vila‐Comamala Joan , David Christian , Metzger Till H. , Bauer Günther 
Published: June 2009

AbstractA submicron X‐ray beam was employed to scan a 3.2 µm SiGe island in two directions. At each scanning position, 2D cuts of the reciprocal space close to the (004) Bragg reflection of the Si substrate were recorded with a CCD. From the position of the SiGe island induced diffuse scattering peak on each CCD frame, we detected and analyzed variations of the strain within a selected single island. Our method does not require the recording of the whole 3D reciprocal space at each position in real space, thus avoiding instability problems during data acquisition. We found changes in the strain which are consistent with finite element calculations of the strain within a model island. The knowledge of the strain distribution within SiGe epitaxial structures is relevant for the correct interpretation of their electronic and optical properties.
In situ X‐ray investigation of SiGe/Si islands grown by liquid phase epitaxy
Authors: Deiter S. , Hanke M. , Eisenschmidt C. , Boeck T. , Teubner T. , Jendritzki U. , Gerlitzke A.‐K. , Schadow G. 
Published: June 2009

AbstractWe report on the in situ observation during liquid phase epitaxy (LPE) of Stranski–Krastanow grown SiGe/Si(001) islands with X‐ray diffraction methods. Therefore, we developed a growth chamber combined with pre‐processed samples which afford LPE under N2 atmosphere (instead of H2 which is normally used for LPE) at a synchrotron beamline. The island evolution is probed with X‐ray diffraction methods from the backside of a thin silicon substrate which floats on the melt. The way towards LPE in situ X‐ray diffraction experiments will be described. Our results show the development of X‐ray diffraction signals in dependence of the current growth state.