bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and characterization of embryonic stem‐like cells derived from in vivo‐produced cat blastocysts
Authors: Yu Xianfeng , Jin Guangzhen , Yin Xijun , Cho Sujin , Jeon Jintae , Lee Sangsuk , Kong Ilkeun
Published: January 2008

Embryonic stem (ES)‐like cells were isolated from in vivo‐produced cat embryos. Total of 101 blastocysts were collected from female cats. The inner cell mass (ICM) were mechanically isolated and cultured on mitomycin‐C‐treated cat embryonic fibroblast feeder layers in medium supplemented with knockout™ Serum Replacement (KSR‐medium) or fetal bovine serum (FBS‐medium). Putative ES‐like cell colonies developed in both KSR‐ and FBS‐medium conditions, but formed domed and flat colonies, respectively. ICM cell attachment and ES‐like cell colony formation were significantly higher in KSR‐medium, but subsequent cell proliferation was significantly lower than in FBS‐medium. For passaging, 32 and 18 colonies in KSR‐ and FBS‐medium were separated by enzymatic dissociation or mechanical disaggregation. Enzymatic dissociation resulted in cell differentiation; however, mechanical disaggregation generated cells that remained undifferentiated over more than four passages and yielded two cat ES‐like cell lines that continued to grow for up to eight passages in FBS‐medium. These cells had typical stem cell morphology, expressed high levels of alkaline phosphatase activity, and were positive for the ES cell‐markers Oct‐4, stage‐specific embryonic antigen‐1 (SSEA‐1), SSEA‐3, and SSEA‐4. These cells formed embryoid bodies (EBs) in suspension culture after extended suspension culture. When simple EBs were cultured on tissue culture plates, they differentiated into several cell types, including epithelium‐like and neuron‐like cells. In addition, EBs were positive for mesoderm marker, desmin. After prolonged in vitro culture, some colonies spontaneously differentiated into beating myocardiocytes, and were positive for alpha‐actinin. These observations indicate that cat ES‐like cells were successfully isolated and characterized from in vivo‐produced blastocysts. Mol. Reprod. Dev. 75: 1426–1432, 2008. © 2008 Wiley‐Liss, Inc.
BCL6 represses NFκB activity in diffuse large B‐cell lymphomas
Authors: Perez‐Rosado A , Artiga MJ , Vargiu P , Sanchez‐Aguilera A , Alvarez‐Barrientos A , Piris MA
Published: January 2008

BCL6 is a transcriptional repressor whose deregulated expression plays a key role in diffuse large B‐cell lymphomas (DLBCLs). BCL6 expression characterizes one of the two main subtypes (GC type) of DLBCL, while the other (ABC type) is recognized by increased NFκB activation. The mechanistic basis of this distinction remains unclear and the BCL6 targets have been only partially explored. Here we describe how NFκB activity is increased after BCL6 silencing by shRNA in DLBCL cells, leading us to propose that BCL6 represses NFκB activity. We also demonstrate that this repression is brought about by a mechanism involving protein–protein interaction between BCL6 and NFκB members, both in vitro and in vivo. Analysis of a series of DLBCLs shows a negative correlation between the expression of NFκB target genes and BCL6. This combined approach using silenced cells and a series of human DLBCL samples leads us to a better understanding of the role of BCL6 as an NFκB regulator in B‐cells. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Expression of coronin‐3 (coronin‐1C) in diffuse gliomas is related to malignancy
Authors: Thal DR , Xavier C‐P , Rosentreter A , Linder S , Friedrichs B , Waha A , Pietsch T , Stumpf M , Noegel AA , Clemen CS
Published: January 2008

Coronin‐3 (coronin‐1C), a homotrimeric F‐actin binding protein, has been shown to be important for cell migration and brain morphogenesis. Here, we present for the first time a detailed analysis of the expression pattern of coronin‐3 in human brain tumours and demonstrate that coronin‐3 expression correlates with malignant phenotype in diffuse gliomas. In general, the expression of coronin‐3 varies in different brain tumour entities. However, in diffuse gliomas, the number of coronin‐3 expressing tumour cells correlates with the degree of malignancy. High‐grade gliomas, such as anaplastic astrocytomas, anaplastic oligodendrogliomas, anaplastic oligoastrocytomas and glioblastomas, show high numbers of tumour cells positive for coronin‐3, while diffuse low‐grade gliomas, such as diffuse astrocytomas, oligodendrogliomas and oligoastrocytomas, exhibit low numbers of coronin‐3‐positive tumour cells. In order to explore and verify a contribution of coronin‐3 to the malignant phenotype of diffuse gliomas, we employed an efficient shRNA‐mediated coronin‐3 knockdown in U373 and A172 human glioblastoma cells. Coronin‐3 knockdown glioblastoma cells exhibited reduced levels of cell proliferation, cell motility and invasion into extracellular matrix compared to control cells. Together, our findings demonstrate evidence for a contribution of coronin‐3 expression in the malignant progression of diffuse gliomas. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Endothelial cells and normal breast epithelial cells enhance invasion of breast carcinoma cells by CXCR‐4‐dependent up‐regulation of urokinase‐type plasminogen activator receptor (uPAR, CD87) expression
Authors: Serratì S , Margheri F , Fibbi G , Di Cara G , Minafra L , Pucci‐Minafra I , Liotta F , Annunziato F , Pucci M , Del Rosso M
Published: January 2008

Here we show the increase of invasion of three breast cancer cell lines (8701‐BC, MDA‐MB‐231 and SKBR3) upon long‐term co‐incubation with culture medium of normal microvascular endothelial cells (MVEC) and normal breast epithelial cells (HB2). The enhancement of invasion relied on the interaction of microvascular endothelial cell and normal breast epithelial cell CXCL12 (SDF1) chemokine, whose expression by breast cancer cells was very low, with the cognate CXCR4 receptor of malignant cells, which resulted in over‐expression of the urokinase‐type plasminogen activator receptor (uPAR) on their surfaces. uPAR over‐expression, showed by RT–PCR and Western blotting, was paralleled by increased urokinase‐type plasminogen activator (uPA) partitioning on the cell surface with respect to the fluid phase, as demonstrated by zymography. Long‐term interaction of SDF1 with CXCR4 stimulated sustained activation of JNK phosphorylation. Blocking antibodies to CXCR4 were able to block the endothelial/epithelial cell‐dependent enhancement of invasion, as well as to inhibit SDF1‐CXCR4‐dependent JNK phosphorylation and uPAR over‐expression of malignant cells. We suggest that acquisition of the angiogenic phenotype by breast cancer cells triggers an amplification loop, in which endothelial cells and normal breast epithelial cells of the tumour cooperate to provide facilitated routes to cell invasion and metastasis and to enhance the aggressive phenotype of cancer cells. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Acid catalyzed 1, 2 Michael addition reaction: a viable synthetic route in designing fullerene core starlike macromolecule
Authors: Singh Rachana , Goswami Thakohari
Published: January 2008

The paper describes a comprehensive investigation to establish the heterophase acid‐catalyzed 1, 2 Michael addition reaction between fullerenol (nucleophile) and substituted acrylates (R = H, CH3, Ph)/vinyl acrylates (electron deficient olefins). The main emphasis is to evaluate structure–property relationship and establish a mechanism for tuning the structure in different operating conditions, which could be useful while adapting this reaction in designing of fullerene core starlike macromolecules. The effect of substituents on the rate of formation of the product is another important aspect covered in the present paper. The most significant outcome of the present investigation are (i) the nature of the product formed has direct bearing with operating process, whereas, (ii) rate of reaction and the properties of the end‐products depends on the nature and position of substituents attached to olefins. Adopting heterogeneous phase reaction scheme, the reaction can be easily controlled at 1, 2 Michael addition stage which otherwise proceeds further to provide cyclic product in single‐phase reaction. The nature of the substituent at β‐carbon of the olefins have the inverse effect on the rate of the reaction. The steric rather than electronic effect of substituents governs the rate of reaction. However, the significant influence of β‐substituents on the properties of the Michael addition products are observed in a more classical manner. The phenyl substituent at the β‐position measured the slowest rate of reaction but imparts highest thermal stability. In such systems, the vinyl substitution on esteric carbon further reduces both the reaction rate and the thermal stability. Copyright © 2008 John Wiley & Sons, Ltd.
Updated Atom/Functional Group and Atom_Code Volume Additivity Parameters for the Calculation of Crystal Densities of Single Molecules, Organic Salts, and Multi‐Fragment Materials Containing H, C, B, N, O, F, S, P, Cl, Br, and I
Authors: Ammon Herman L.
Published: January 2008

Data for crystal structures with ≤10 fragments per asymmetric unit from the Cambridge Structural Database were used to update and extend our previously described databases. Atom and functional group volumes and densities were determined for organic compounds with the elements H, C, B, N, O, F, P, S, Cl, Br, I, and halide anions. The datasets included organic ions and multi‐fragment structures. Linear and nonlinear volumes and linear densities were determined for 109 predefined atoms/functional groups from ∼41000 crystal structure data. An updated volume database for atom_codes, which are automatically defined by the atoms and their connections in a dataset, was determined in separate calculations with 2805 atom_codes defined for ∼48000 structures. The atom_code extension to 6‐coordinate C and B allowed carboranes to be modeled. The average percent difference between the observed and calculated densities is about 2%.
A novel transcript from the KLKP1 gene is androgen regulated, down‐regulated during prostate cancer progression and encodes the first non‐serine protease identified from the human kallikrein gene locus
Authors: Kaushal Aneel , Myers Stephen A. , Dong Ying , Lai John , Tan Olivia L. , Bui Loan T. , Hunt Melanie L. , Digby Matthew R. , Samaratunga Hemamali , Gardiner Robert A. , Clements Judith A. , Hooper John D.
Published: January 2008

BACKGROUND

The kallikrein‐related (KLK) serine protease, prostate specific antigen is the current marker for prostate cancer (PCa). Other members of the KLK family are also emerging as potential adjunct biomarkers for this disease. Our aim was to identify and characterize novel KLK‐related genes with potential as PCa bio‐markers.

METHODS

Low stringency DNA screening was coupled with amplification techniques to identify novel sequences. Transcripts were examined by Northern blot, RT‐PCR, and in situ hybridization analysis and in silico bioinformatics approaches. Protein characterization was performed by Western blot and confocal microscopy analysis. Gene regulation studies were performed by quantitative PCR and promoter reporter assays.

RESULTS

We identified a novel kallikrein‐related mRNA designated KRIP1 (kallikrein‐related, expressed in prostate 1) which, together with the recently reported ΨKLK1 and KLK31P transcripts, is transcribed from KLKP1; a gene evolved from, and located within, the KLK locus. Significantly, in contrast to these other non‐coding KLKP1 transcripts, the KRIP1 mRNA generates an ∼18 kDa intracellular protein—the first non‐serine protease identified from the KLK locus. KRIP1 mRNA is abundant only in normal prostate and is restricted to cells of epithelial origin in normal and diseased glands. Ligand binding of the androgen receptor increases transcription from the KLKP1 gene. Consistently, KRIP1 mRNA levels are lower in PCa samples compared to benign prostatic hyperplasia.

CONCLUSIONS

Transcription from KLKP1 is reduced as cells de‐differentiate on the pathway to malignancy. KLKP1/KRIP1 has potential as a marker of both PCa progression and recent evolutionary events within the KLK locus. Prostate 68: 381–399, 2008. © 2008 Wiley‐Liss, Inc.
Differential localization of MT1‐MMP in human prostate cancer tissue: Role of IGF‐1R in MT1‐MMP expression
Authors: Sroka Isis C. , McDaniel Kathy , Nagle Raymond B. , Bowden G. Tim
Published: January 2008

Background

MT1‐MMP is a metalloproteinase involved in prostate cancer metastasis. The IGF‐1R is a tyrosine kinase receptor involved with tumor progression and metastasis. The purpose of this investigation was to examine MT1‐MMP and IGF‐1R expression and localization in prostate cancer tissues and explore the role of IGF‐1R in regulating MT1‐MMP in prostate cancer cell lines.

Methods

Immunohistochemistry was utilized to study MT1‐MMP and IGF‐1R expression in human prostate tissues. IGF‐1R regulation of MT1‐MMP expression was determined by gene promoter analysis, quantitative RT‐PCR and Western blot analysis following pharmacological inhibition of the receptor in PC‐3N cells and treatment of LNCaP cells with androgen and IGF‐1.

Results

MT1‐MMP expression was high in the apical regions of the luminal cells in PIN and prostate cancer and less intense in the basalateral regions of benign tissues. IGF‐1R was expressed primarily in the basal cells of normal glands and highly expressed in prostate cancer. Inhibition of IGF‐1R in PC‐3N cells decreased MT1‐MMP expression and treatment of LNCaP cells with a synthetic androgen and IGF‐1 increased MT1‐MMP expression.

Conclusions

These data demonstrate that MT1‐MMP is highly expressed in the apical cytoplasmic regions of the luminal cells in PIN and prostate cancer when compared to basalateral cytoplasmic membrane staining in benign glands. Additionally, we demonstrate that IGF‐1R is highly expressed in human prostate carcinoma. These findings suggest that MT1‐MMP localization and IGF‐1R expression in prostate carcinoma could be predictive biomarkers for aggressive disease and support IGF‐1R as a promising therapeutic target to decrease processes of prostate cancer metastasis. Prostate 68: 463–476, 2008. © 2008 Wiley‐Liss, Inc.
Androgen receptor‐dependent regulation of Bcl‐xL expression: Implication in prostate cancer progression
Authors: Sun Aijing , Tang Jianxi , Hong Yan , Song Jiawu , Terranova Paul F. , Thrasher J. Brantley , Svojanovsky Stan , Wang Hong‐gang , Li Benyi
Published: January 2008

Background

Recently we reported that silencing the androgen receptor (AR) gene reduced Bcl‐xL expression that was associated with a profound apoptotic cell death in prostate cancer cells. In this study we further investigated AR‐regulated Bcl‐xL expression.

Methods

Prostate cancer cell line LNCaP and its sublines, LNCaP/PURO and LNCaP/Bclxl, were used for cell proliferation assay and xenograft experiments in nude mice. Luciferase gene reporters driven by mouse or human bcl‐x gene promoter were used to determine androgen regulation of Bcl‐xL expression. RT‐PCR and Western blot assays were conducted to assess Bcl‐xL gene expression. Chromatin immunoprecipitation assay was performed to determine AR interaction with Bcl‐xL promoter. Bcl‐xL‐induced alteration of gene expression was examined using cDNA microarray assay.

Results

In cultured prostate cancer LNCaP cells, androgen treatment significantly increased Bcl‐xL expression at mRNA and protein levels via an AR‐dependent mechanism. Promoter analyses demonstrated that the AR mediated androgen‐stimulated bcl‐x promoter activation and that the AR interacted with bcl‐x promoter. Enforced expression of Bcl‐xL gene dramatically increased cell proliferation in vitro and promoted xenograft tumor growth in vivo. Genome‐wide gene profiling analysis revealed that Bcl‐xL expression was significantly higher in metastatic and castration‐resistant diseases compared to normal prostate tissues or primary cancers. Bcl‐xL overexpression significantly increased the expression of cyclin D2, which might be responsible for Bcl‐xL‐induced cell proliferation and tumor growth.

Conclusions

Taken together, our data strongly suggest that androgen stimulates Bcl‐xL expression via the AR and that increased Bcl‐xL expression plays a versatile role in castration‐resistant progression of prostate cancer. Prostate 68: 453–461, 2008. © 2008 Wiley‐Liss, Inc.
Triiodothyronine modulates cell proliferation of human prostatic carcinoma cells by downregulation of the B‐Cell translocation gene 2
Authors: Tsui Ke‐Hung , Hsieh Wen‐Chi , Lin Mei‐Hsien , Chang Phei‐Lang , Juang Horng‐Heng
Published: January 2008

Background

Studies suggest that triiodothyronine (T3) and cognate nuclear receptors (hTR) are involved in regulation of prostatic cell growth and differentiation. To probe mechanisms for T3 effects, we studied prostate carcinoma cells, investigating the effect of T3 on expression of the B‐cell translocation gene 2 (BTG2), which regulates the G1/S transition of the cell cycle.

Methods

Effects of T3 on cell proliferation were determined by 3H‐thymidine incorporation. T3 modulation of BTG2 expression was investigated using immunoblots, Northern blots, and transient gene expression assays. The putative T3 response element was determined by electrophoretic mobility shift assay.

Results

T3 (0.1–1,000 nM) enhanced threefold the proliferation of prostate carcinoma cells and human androgen‐dependent prostate carcinoma cells (LNCaP), but not PC‐3 cells. T3 also inhibited BTG2 gene expression in LNCaP cells. Reporter assays showed that T3 downregulates by 50% promoter activity of the BTG2 gene in LNCaP cells but not PC‐3 cells or thyroid‐hormone receptor (TRβ1)‐overexpression PC‐3 cells. Deleting the putative thyroid hormone response element (TRE; AGCGATGACCTCAGCG) blocked the inhibitory effect of T3 on BTG2 promoter activity. Electrophoretic mobility shift assays with purified TRβ1 from in vitro translation, or with nuclear extracts from LNCaP cells and PC‐3 cells, demonstrated the presence of T3 receptor binding sites in the TRE region.

Conclusions

These results suggested that the T3 upregulates proliferation of LNCaP cells by downregulating BTG2 gene expression through the consensus TRE pathway. Prostate 68: 610–619, 2008. © 2008 Wiley‐Liss, Inc.
Enfuvirtide effects on human erythrocytes and lymphocytes functional properties
Authors: Vieira Catarina R. , Castanho Miguel , Saldanha Carlota , Santos Nuno C.
Published: January 2008

Enfuvirtide (T‐20) is the first inhibitor of human Immunodeficiency Virus type‐1 (HIV‐1) entrance on a target cell approved for clinical use. Recent studies indicated that its action mechanism involves the interaction with the membrane surface, increasing the concentration in the site of action. In the present study, the in vitro interaction between enfuvirtide and blood cells of healthy human donors, namely erythrocytes and lymphocytes, and the peptide effect on plasma and lymphocyte suspensions supernatant ions were evaluated, in order to better characterize the action of this peptide. Enfuvirtide causes a decrease in the concentration of hemoglobin and in the percentages of methemoglobin and carboxyhemoglobin, together with increased values of P50, pCO2, and [HCO3−], and significant decreases of pO2 and pH, in blood plasma. The supernatants of lymphocyte suspensions derived from blood incubated with enfuvirtide presented a decrease in pH and [HCO3−]. Fluorescence anisotropy measurements of 1,6‐diphenyl‐1,3,5‐hexatriene (DPH) and 1‐(4‐(trimethylamino)‐phenyl)‐6‐phenyl‐1,3,5‐hexatriene (TMA‐DPH), used to assess erythrocyte and lymphocyte membrane fluidity, did not yield enfuvirtide‐induced changes (an effect could be expected due to peptide partition to lipid bilayers). Erythrocytes incubated with high enfuvirtide concentrations showed a significant decrease in osmotic fragility. As for erythrocyte deformability, enfuvirtide leads to increased elongation indexes for low shear stress values, whereas for high shear stress values it has the opposite effect. Despite the observed statistically significant variations in several parameters, these enfuvirtide‐induced changes are not expected to lead to any detectable biomedical outcome for enfuvirtide‐treated patients. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.
Temperature and pH effects on biophysical and morphological properties of self‐assembling peptide RADA16‐I
Authors: Ye Zhaoyang , Zhang Hangyu , Luo Hanlin , Wang Shunkang , Zhou Qinghan , DU Xinpeng , Tang Chengkang , Chen Liyan , Liu Jingping , Shi Ying‐Kang , Zhang Er‐Yong , Ellis‐Behnke Rutledge , Zhao Xiaojun
Published: January 2008

It has been found that the self‐assembling peptide RADA 16‐I forms a β‐sheet structure and self‐assembles into nanofibers and scaffolds in favor of cell growth, hemostasis and tissue‐injury repair. But its biophysical and morphological properties, especially for its β‐sheet and self‐assembling properties in heat‐ and pH‐denatured conditions, remain largely unclear. In order to better understand and design nanobiomaterials, we studied the self‐assembly behaviors of RADA16‐I using CD and atomic force microscopy (AFM) measurements in various pH and heat‐denatured conditions. Here, we report that the peptide, when exposed to pH 1.0 and 4.0, was still able to assume a typical β‐sheet structure and self‐assemble into long nanofiber, although its β‐sheet content was dramatically decreased by 10% in a pH 1.0 solution. However, the peptide, when exposed to pH 13.0, drastically lost its β‐sheet structure and assembled into different small‐sized globular aggregates. Similarly, the peptide, when heat‐denatured from 25 to 70 °C, was still able to assume a typical β‐sheet structure with 46% content, but self‐assembled into small‐sized globular aggregates at much higher temperature. Titration experiments showed that the peptide RADA16‐I exists in three types of ionic species: acidic (fully protonated peptide), zwitterionic (electrically neutral peptide carrying partial positive and negative charges) and basic (fully deprotonated peptide) species, called ‘super ions’. The unordered structure and β‐turn of these ‘super ions’ via hydrogen or ionic bonds, and heat Brownian motion under the above denatured conditions would directly affect the stability of the β‐sheet and nanofibers. These results help us in the design of future nanobiomaterials, such as biosensors, based on β‐sheets and environmental changes. These results also help understand the pathogenesis of the β‐sheet‐mediated neuronal diseases such as Alzheimer's disease and the mechanism of hemostasis. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.
Enhancement of luminescence in ZnMgO thin‐film nanophosphors and application for white light generation
Authors: Chawla Santa , Jayanthi K. , Chander Harish
Published: January 2008

A series of ZnMgO thin‐film nanophosphors with varied Zn:Mg ratio has been prepared by chemical bath deposition. The structure, photoluminescence, time‐resolved decay and chromaticity of the films are presented. ZnMgO films absorb light efficiently in the near UV (330–400 nm) and the emission covers a large part of the visible spectrum. Luminescence enhancement is maximum for 25% Mg. All ZnMgO films show luminescence lifetimes in the microsecond range while low Mg content (0–10%) films also exhibit fast decay (10–10 s). Measured colorimetric coordinates of (0.28, 0.32) when excited by 350 nm light make them suitable for generation of white light in conjunction with near UV LEDs. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the improvement of the electroluminescent signal of organic light‐emitting diodes by the presence of an ultrathin metal layer at the interface organic/ITO
Authors: Bernède J. C. , Martinez F. , Neculqueo G. , Cattin L.
Published: January 2008

Under DOI 10.1002/pssa.200723206 erroneously a paper was published online in January 2008 which already had been published elsewhere. Please find this paper, entitled “On the improvement of the electroluminescent signal of organic light emitting diodes by the presence of an ultra‐thin metal layer at the interface organic/ITO” by J. C. Bernède, F. Martinez, G. Neculqueo, and L. Cattin under DOI 10.1002/pssr.200701217, published in phys. stat. sol. (RRL) 2, No. 1, 10–12 (2008). (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystallization behavior of Sb70Te30 and Ag3In5Sb60Te32 chalcogenide materials for optical media applications
Authors: Lee M. L. , Shi L. P. , Tian Y. T. , Gan C. L. , Miao X. S.
Published: January 2008

Addition of In and Ag into eutectic Sb70Te30 fast‐growth material was studied. We explored the optical transitions and crystallization kinetics of Sb70Te30 and Ag3In5Sb60Te32 recording films. The results showed that Ag3In5Sb60Te32 has a higher crystallization temperature but a similar melting point compared to Sb70Te30. In both the crystalline and amorphous states, addition of Ag and In increased the refractive index and decreased the extinction coefficient of Sb70Te30. Ag3In5Sb60Te32 has better thermal stability and a lower crystallization speed than Sb70Te30 film. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Contact effects in Cu(TCNQ) memory devices
Authors: Hefczyc Artur , Beckmann Lars , Becker Eike , Johannes Hans‐Hermann , Kowalsky Wolfgang
Published: January 2008

Reversible electrical switching and memory effects have been reported for a range of organic materials and device configurations. The underlying mechanism is still not clarified and subject of investigations. We present a detailed summary of our experiments on the influence of the contacts on the switching properties of bistable Cu(TCNQ) devices. We have electrically characterized devices with a number of different contact metals as well as different contact and device configurations. In the case of noble metal top contacts, switching was only observed when the contact area was small or when an oxide interlayer was used. These devices reversibly lost there switching properties when no oxygen was present in the ambience. We observed a dependence of the switching polarity on the work function of the contact met al. While devices in the commonly used stacked configuration have an asymmetric electrical characteristic, we were able to produce symmetric, planar devices with symmetric switching behaviour. A device structure comprising three electrodes allowed us to localize the switching process in the vicinity of the metal electrode with the lower work function. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical studies of optical gain of coupled quantum wells based on InGaAsN material system
Authors: Wartak M. S. , Weetman P.
Published: January 2008

The optical gain of two coupled quantum wells fabricated from a new material system of InGaAsN/GaAs is studied by applying 10‐band k·p Hamiltonian matrix. A self‐consistent scheme which involves simultaneous solution of matrix Schrödinger and Poisson equations was applied. The optical gain spectra were obtained and analyzed for various values of nitrogen composition and barrier widths. They show optimum values for particular barrier width, although the variations are not significant. However, the magnitude of gain peak undergoes significant changes when varying nitrogen composition. The determined parameters and their variations can play significant role in designing practical structures based on InGaAsN/GaAs material systems. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phonons in Bx Ga1–xN/GaN epilayers studied by means of UV Raman scattering
Authors: Cuscó R. , Alarcón‐Lladó E. , Ibáñez J. , Artús L. , Gautier S. , Ougazzaden A.
Published: January 2008

We present UV Raman scattering measurements on Bx Ga1–x N epilayers with boron composition up to 3.6%. The resonant enhancement of the longitudinal optical modes allows us to detect multiphonon scattering by A1(LO) modes. For low boron compositions (≲2%), both the E2 and the A1(LO) modes show a consistent frequency increase with boron composition due to alloying effects. Higher disorder and expansive strain are observed in alloys with higher boron content. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tight binding modelling of electronic structure of GaPN/GaP, InAsN/InAs and GaAsN/GaAs heterostructures
Authors: Akıncı Özden , Gürel H. Hakan , Ünlü Hilmi
Published: January 2008

We present a second nearest neighbor semi‐empirical sp3s*tight binding model to calculate the electronic band structure of nitride/arsenide or phosphide heterostructures. The sp3s*model Hamiltonian includes the spin‐orbit coupling of p‐states, second nearest neighbor (2NN) atomic interactions. Atomic energy levels and bond lengths of ternary semi‐ conductors are taken as nonlinear function of alloy com‐ position. The model findings for InAsN/InAs, GaPN/GaP and GaAsN/GaAs structures are in excellent agreement with experiment for the band gaps at Γ, L and X symmetry points. It is found that the bulk band structure properties and lattice mismatch strain have significant effects on band offsets and GaPN/GaP, InAsN/InAs and GaAsN/GaAs heterostructures are type II for small composition (0.0 < x < 0.50) and become type I for large composition 0.50 < x < 1.0. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Enhanced radiation hardness of ZnO nanorods versus bulk layers
Authors: Burlacu A. , Ursaki V. V. , Lincot D. , Skuratov V. A. , Pauporte T. , Rusu E. , Tiginyanu I. M.
Published: January 2008

It is shown that ZnO nanorods grown by MOCVD exhibit enhanced radiation hardness against high energy heavy ion irradiation as compared to bulk layers. The decrease of the luminescence intensity induced by 130 MeV Xe+23 irradiation at a dose of 1.5 × 1014 cm–2 in ZnO nanorods is nearly identical to that induced by a dose of 6 × 1012 cm–2 in bulk layers. The change in the nature of electronic transitions responsible for luminescence occurs at an irradiation dose around 1 × 1014 cm–2 and 5 × 1012 cm–2 in nanorods and bulk layers, respectively. High energy heavy ion irradiation followed by thermal annealing is also effective on the quality of ZnO nanorods grown by electrodeposition. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigating aluminum thin films properties by stochastic analysis
Authors: Hosseinabadi S. , Mortezaali A. , Masoudi A. A.
Published: January 2008

In this article, we investigate about stochastic properties of a thin film such as aluminum thin film that is formed by thermal evaporation in high vacuum. So we prepare thin films with different thicknesses on glass surfaces in high vacuum chamber with 10−6 torr. Then, we use Atomic Force Microscopy (AFM), for determining the height fluctuations of aluminum thin films in different growth stages and use an inverse method that utilizes data from AFM to construct a simple equation that governs the stochastic process and a relation between stochastic parameters such as roughness, correlation and Markov length, drift, and diffusion coefficients during the growth process. Also we show that aluminum thin films, during growth by evaporating in high vacuum chamber, have a mono fractal behavior in small distances(little than 100 nm) on the surfaces. Copyright © 2008 John Wiley & Sons, Ltd.
Iridium‐Complex‐Functionalized Fe3O4/SiO2 Core/Shell Nanoparticles: A Facile Three‐in‐One System in Magnetic Resonance Imaging, Luminescence Imaging, and Photodynamic Therapy
Authors: Lai Chih‐Wei , Wang Yu‐Hsiu , Lai Cheng‐Hsuan , Yang Meng‐Ju , Chen Chun‐Yen , Chou Pi‐Tai , Chan Chi‐Shun , Chi Yun , Chen Yu‐Chun , Hsiao Jong‐Kai
Published: January 2008

Highly uniform Fe3O4/SiO2 core/shell nanoparticles functionalized by phosphorescent iridium complexes (Ir) have been strategically designed and synthesized. The Fe3O4/SiO2(Ir) nanocomposite demonstrates its versatility in various applications: the magnetic core provides the capability for magnetic resonance imaging and the great enhancement of the spin–orbit coupling in the iridium complex makes it well suited for phosphorescent labeling and simultaneous singlet oxygen generation to induce apoptosis.
A method for re‐planning of software releases using discrete‐event simulation
Authors: Al‐Emran Ahmed , Pfahl Dietmar , Ruhe Günther
Published: January 2008

Software release planning can be described as a process consisting of the following three phases: (i) strategic release planning, i.e. the assignment of features to subsequent releases, (ii) operational release planning, i.e. the allocation of resources to tasks within each individual release, and (iii) dynamic re‐planning, i.e. the revision of plans to handle unexpected changes imposed on product/project managers responsible for the realization of individual releases. Example changes include the addition or removal of features and/or developers, adjustments due to over‐estimated developer productivity, or under‐estimated work volume of feature‐specific tasks, and adjusted degrees of task dependencies. The research presented in this article mainly focuses on phase (iii), in conjunction with phase (ii), of the release planning process, assuming that phase (i) has already been completed. For that purpose, we present a hybrid intelligence decision‐support method PRP (Planning/Re‐planning), and as its integral part a discrete‐event simulation model called DynaReP (Dynamic Re‐planner). The applicability, effectiveness, and efficiency of the proposed method and model are illustrated through a series of typical release planning and re‐planning scenarios on operational level. Copyright © 2008 John Wiley & Sons, Ltd.
Effects of service‐oriented architecture on software development lifecycle activities
Authors: Lewis Grace A. , Morris Edwin , Simanta Soumya , Wrage Lutz
Published: January 2008

Service‐Oriented Architecture (SOA) is having a major impact on the development of software systems because of its potential for increased business agility, adaptability of applications, interoperability between systems, and reuse of legacy assets. However, organizations often make decisions on SOA adoption without carefully analyzing the implications of their decisions. This article outlines a set of common misconceptions about SOA and suggests ways in which software development lifecycle activities can be adapted to account for the characteristics of SOA‐based systems. Copyright © 2008 John Wiley & Sons, Ltd.
Association between intrapulmonary arterial Doppler parameters and degree of lung growth as measured by lung‐to‐head ratio in fetuses with congenital diaphragmatic hernia
Authors: Moreno‐Alvarez O. , Hernandez‐Andrade E. , Oros D. , Jani J. , Deprest J. , Gratacos E.
Published: January 2008

Objectives

To describe the association between the intrapulmonary circulation and the degree of lung growth in fetuses with congenital diaphragmatic hernia (CDH).

Methods

Thirty‐six fetuses with isolated left CDH at 22–29 weeks of gestation were studied. Four groups were defined according to lung‐to‐head ratio (LHR), expressed as the ratio of observed to expected LHR for gestational age (O/E LHR). Pulsatility index (PI), peak systolic velocity (PSV), peak early‐diastolic reversed flow (PEDRF), end‐diastolic velocity (EDV), acceleration time (AT), time averaged velocity (TAV) and the ratio AT to ejection time (AT/ET) were measured in all fetuses in the proximal arterial branch of both lungs. For analysis, Doppler values were converted to Z‐scores.

Results

It was possible to record all Doppler parameters from the contralateral lung of all CDH fetuses, and from the ipsilateral lung in 28 (77.7%). PEDRF significantly increased in relation to the decrease in O/E LHR in both lungs (contralateral: r = − 0.65, P = 0.01; ipsilateral: r = − 0.43, P = 0.02). PI increased significantly with the reduction in O/E LHR but only on the side contralateral to the hernia (r = − 0.55, P = 0.02). In the ipsilateral pulmonary artery, PI values showed a significant overall increase but no differences were observed among the O/E LHR groups. PSV, EDV and TAV were reduced in both lungs with respect to normal values, but no association was found with the O/E LHR. No changes in AT or AT/ET were observed in either lung.

Conclusions

PEDRF is quick and easy to calculate, and showed the strongest and most consistent correlation with O/E LHR. The association between PEDRF and LHR might be an additional parameter that could help to establish prognosis in fetuses with CDH. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Prognostic Models for Predicting Death after Hepatectomy in Individuals with Hepatic Metastases from Colorectal Cancer
Authors: Kanemitsu Yukihide , Kato Tomoyuki
Published: January 2008

Background

Appropriate cancer treatment policies should include an accurate estimate of a patient’s baseline risk of death, determined by the tumor load. Few prognostic models have reached the stage at which they can be used to select patients who would benefit from hepatectomy for metastatic colorectal cancer. Establishing the prognosis of patients with hepatic metastases from colorectal cancer is an important part of their evaluation and treatment.

Methods

Pre‐ and post‐treatment prognostic nomograms were developed using Cox regression and multiple imputation from 578 patients with hepatic metastases from colorectal cancer who were candidates for hepatectomy.

Results

The preoperative nomogram included the following prognostic factors: primary histology, number of metastatic lymph nodes associated with the primary lesion, number of hepatic tumors, extrahepatic disease, and prehepatectomy carcinoembryonic antigen level. Plots of predicted versus actual outcomes suggested that the nomogram was well calibrated for predicting death after hepatectomy. The concordance index of the nomogram was 0.66, higher than those of other models for hepatic metastatic colorectal cancer in the literature. A postoperative nomogram was also prepared.

Conclusions

These models have improved predictive ability in individuals with hepatic metastases from colorectal cancer, which may be helpful in counseling patients and making treatment decisions.
Disparities in Oncologic Surgery
Authors: Greenberg Caprice C. , Weeks Jane C. , Stain Steven C.
Published: January 2008

Surgical oncology is one of the most frequently studied surgical specialties with regard to disparities in quality of care. There is variation in the care received according to nonclinical factors such as age, race and ethnicity, education, income, and even geographic region. Differences exist with regard to who gets treatment, what treatment is received, and the outcomes of those treatments. Although the existence of such disparities is no longer in doubt, the etiology is still being investigated. Ongoing research and quality improvement initiatives move beyond the mere description of existing disparities in one of three ways: (1) identifying and understanding the factors that lead to disparities; (2) advancing available methods to measure and track disparities; and (3) developing an approach to improvement. In this article, we start out by offering a framework to describe potential factors that lead to disparities, using examples from surgical oncology. We then describe the approaches to measuring and tracking disparities that are being used in research and quality improvement. Finally, we attempt to illustrate how all of these factors interact and offer some potential strategies to close the gap and alleviate disparities within the discipline.
Viscoelastic Properties of a Biological Hydrogel Produced from Soybean Oil
Authors: Xu Jingyuan , Liu Zengshe , Erhan Sevim Z.
Published: January 2008

Hydrogels formed from biopolymers or natural sources have special advantages because they may have biodegradable and biocompatible properties. The viscoelastic properties of a newly developed biological hydrogel made from epoxidized soybean oil (ESO) were investigated. The material called HPESO is a hydrolytic product of polymerized ESO (PESO). HPESO exhibited viscoelastic solid or gel behavior above 2% (wt. %) concentration at room temperature and viscous liquid behavior at 55 °C. The thermal assembly disassembly reassembly function of the HPESO hydrogel was completely reversible. The viscoelastic properties of HPESO were dependent on concentration. Analysis of modulus and concentration dependence and stress relaxation measurement indicated that HPESO was a physical gel where the cross‐linkers between the molecules were physical junctions. HPESO hydrogel also exhibited fast initial recovery of its viscoelastic properties after being subjected to mechanical shear disruption. The function and behavior of the HPESO hydrogel suggest that this biomaterial may be suitable for applications in drug delivery and scaffolds of bioengineering and tissue engineering.
The Church, Society and Politics: A View from Moscow
Authors: Alexius Patriarch
Published: January 2008

This article makes the point that politicians should not use religion as a tool for power but should instead promote religious values as a means to achieve the common good. A free church and a religious society are necessary conditions for genuine peace, both for individuals and for society as a whole.
Polycystin‐1 induced apoptosis and cell cycle arrest in G0/G1 phase in cancer cells
Authors: Zheng Rong , Zhang Zheng , Lv Xiaoyan , Fan JunMing , Chen Ye , Wang Yidong , Tan Ruizhi , Liu Yuhang , Zhou Qin
Published: January 2008

Studies have shown that polycystin‐1, encoded by PKD1, the major ADPKD, may have a central role in regulating both apoptosis and proliferation, which could prevent the malignant transformation of affected cells. However, as a putative tumor suppressor, direct studies on the possibility that polycystin‐1 may play a role in cancer cells' biological properties have not yet been reported. We have demonstrated that the apoptosis of cancer cells was induced by overexpression of polycystin‐1. After transfection with polycystin‐1, three cancer cell lines, HepG2, A549, and SW480, showed significantly increased apoptosis compared with the respective control groups. This was accompanied by cell cycle arrest at G0/G1 phase, whereas cell proliferation was not significantly affected. Overexpression of polycystin‐1 induces apoptosis in cancer cells, at least partially, through Wnt and a caspase‐dependent pathway.
Adolescent social development and chronic pain
Authors: Eccleston Christopher , Wastell Sarah , Crombez Geert , Jordan Abbie
Published: January 2008

Adolescents with chronic pain report disability, distress and reduced social functioning. A clinical sample of 110 adolescents, with a mean four year history of pain, was investigated for the psychosocial impact of pain on social development. All participants completed a range of self‐report measures of pain intensity, disability, distress, social and family functioning. Also completed was the Bath Adolescent Pain Questionnaire, including its development subscale. The development subscale measures the extent to which adolescents perceive themselves to be ahead or behind their peers on 11 aspects of social development. Three related analyses were undertaken. First, over 50% of adolescents reported themselves to be less developed than their peers on four or more aspects. The item with the highest endorsement of being ahead compared with peers was “dealing with problems”. Second, factor analyses revealed three factors of adolescent social development labelled ‘independence’, ‘emotional adjustment’ and ‘identity formation’. Third, regression analyses revealed that peer support had a positive effect on all three factors, disability and anxiety had a negative effect on perceptions of independence, greater family dysfunction had a negative effect on emotional adjustment, and depressive mood had a negative effect on identity formation. Pain intensity had a negative effect on all three factors. Findings suggest that adolescents with chronic pain judge themselves to be less developed than their peers. Pain intensity has a negative effect on this perception, but peer relations may play a protective role: strong peer relationships are associated with positive social comparisons of the level of social development.
Practicality of a computerized system for cognitive assessment in the elderly
Authors: Fillit Howard M. , Simon Ely S. , Doniger Glen M. , Cummings Jeffrey L.
Published: January 2008

Background

Early detection and diagnosis are critical to dementia care. However, many early cases remain undiagnosed as a result of the impracticality of neuropsychological testing, particularly in primary care. Mindstreams is an office‐based computerized system for measuring cognitive function in multiple domains, with demonstrated validity, test‐retest reliability, and sensitivity to treatment effects. This study evaluated its feasibility for assessment of the elderly.

Methods

Usability data were collected after each of 2,888 consecutive initial‐visit testing sessions at the first 11 clinical centers to use Mindstreams. The χ2 goodness‐of‐fit test was employed to determine whether patients and supervisors more often rated tests easy versus hard to use. Separate analyses were run for non–computer users, patients older than 75 years, and poor performers (≤1 standard deviation on overall battery performance).

Results

For all patients (n = 2,888; age, 64.7 ± 18.2 years), 83% rated the tests easy to use (P < .001). Seventy‐three percent of non–computer users, 70% of patients older than 75, and 69% of poor performers rated them easy to use (Ps < .001). Supervisor ratings and ease of understandability ratings were similar. For all patients, 76% of supervisor ratings indicated no patient frustration (P < .001). Seventy‐eight percent of ratings for non–computer users, 76% for patients older than 75, and 74% for poor performers indicated no frustration (Ps < .001).

Conclusions

Mindstreams was easily employed, including in patients with considerable cognitive impairment, supporting its practicality for in‐office cognitive assessment of the elderly. The availability of such valid and practical assessment suggests the feasibility of integrating the technology within a clinical algorithm for improved detection of cognitive decline.
Disease‐modifying approaches to Alzheimer's disease: Challenges and opportunities—Lessons from donepezil therapy
Authors: Sabbagh Marwan N. , Richardson Sharon , Relkin Norman
Published: January 2008

The era of disease modification as a therapeutic option for Alzheimer's disease (AD) is upon us. With dozens of novel drugs in development, there is more need than ever to develop biomarkers that distinguish normal aging from AD and AD from other dementias, track changes over time as disease progresses, and respond to interventions. Future trials will need to weight biomarker outcomes equal to cognitive outcomes especially when the biomarkers are linked to specific mechanisms, such as changes to beta amyloid (Aβ) deposition or brain volume. Since the advent of donepezil as a treatment for AD, new mechanisms of action of this molecule have been discovered. In this perspective, we review trial design and discuss the use of biomarkers by using lessons learned from previous trials conducted with cholinergic therapy.