631 research outputs found

    Thymidine phosphorylase in cancer cells stimulates human endothelial cell migration and invasion by the secretion of angiogenic factors

    Get PDF
    BACKGROUND: Thymidine phosphorylase (TP) is often overexpressed in tumours and has a role in tumour aggressiveness and angiogenesis. Here, we determined whether TP increased tumour invasion and whether TP-expressing cancer cells stimulated angiogenesis. METHODS: Angiogenesis was studied by exposing endothelial cells (HUVECs) to conditioned medium (CM) derived from cancer cells with high (Colo320TP1 = CT-CM, RT112/TP = RT-CM) and no TP expression after which migration (wound-healing-assay) and invasion (transwell-assay) were determined. The involvement of several angiogenic factors were examined by RT-PCR, ELISA and blocking antibodies. RESULTS: Tumour invasion was not dependent on intrinsic TP expression. The CT-CM and RT-CM stimulated HUVEC-migration and invasion by about 15 and 40%, respectively. Inhibition by 10 mu M TPI and 100 mu M L-dR, blocked migration and reduced the invasion by 50-70%. Thymidine phosphorylase activity in HUVECs was increased by CT-CM. Reverse transcription-polymerase chain reaction revealed a higher mRNA expression of bFGF (Colo320TP1), IL-8 (RT112/TP) and TNF-alpha, but not VEGF. Blocking antibodies targeting these factors decreased the migration and invasion that was induced by the CT-CM and RT-CM, except for IL-8 in CT-CM and bFGF in RT-CM. CONCLUSION: In our cell line panels, TP did not increase the tumour invasion, but stimulated the migration and invasion of HUVECs by two different mechanisms. Hence, TP targeting seems to provide a potential additional strategy in the field of anti-angiogenic therapy

    Modelling of faults for chemical batch reactor using artificial neural network and fuzzy logic [TP1-1185].

    Get PDF
    Setiap proses kimia cenderung untuk mengalami kegagalan. Situasi ini memaksa industri dan penyelidik mencari teknik bersesuaian bagi mengesan kegagalan secepat yang mungkin. Every chemical processes prones to failure. This situation enforces the researchers and industrial to find the appropriate techniques to detect a process failure as early as possible

    Anticipated Fiscal Policy and Adaptive Learning

    Get PDF
    We consider the impact of anticipated policy changes when agents form expectations using adaptive learning rather than rational expectations. To model this we assume that agents combine limited structural knowledge with a standard adaptive learning rule. We analyze these issues using two well-known set-ups, an endowment economy and the Ramsey model. In our set-up there are important deviations from both rational expectations and purely adaptive learning. Our approach could be applied to many macroeconomic frameworks.Taxation, expectations, Ramsey model.

    Polymorphism in TNP-1 gene of Murrah buffalo bulls

    Get PDF
    Transition nuclear proteins (TPs), the major proteins found in chromatin of condensing spermatids, have been reported to be important for histone displacement and chromatin condensation during mammalian spermatogenesis. In the present study, transition nuclear protein-1 (TNP-1) gene was analyzed using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technique- to detect polymorphism in Murrah bulls. Analysis of TNP-1 gene sequence of Murrah buffalo revealed 3 single nucleotide polymorphisms (SNPs) at 205, 340 and 346 bp positions of intronic region. The effect of this polymorphism was explored on individual motility, mass activity and maturation of spermatozoa. Analysis of variance indicates that two variants C and D of Murrah buffalo had significant effect on spermatozoal maturation. However, their effects on individual motility and mass activity was non significant.Key words: TNP-1 gene, polymorphism, infertility, sub-fertility, sperm maturation, SNP

    Analysis of group evolution prediction in complex networks

    Full text link
    In the world, in which acceptance and the identification with social communities are highly desired, the ability to predict evolution of groups over time appears to be a vital but very complex research problem. Therefore, we propose a new, adaptable, generic and mutli-stage method for Group Evolution Prediction (GEP) in complex networks, that facilitates reasoning about the future states of the recently discovered groups. The precise GEP modularity enabled us to carry out extensive and versatile empirical studies on many real-world complex / social networks to analyze the impact of numerous setups and parameters like time window type and size, group detection method, evolution chain length, prediction models, etc. Additionally, many new predictive features reflecting the group state at a given time have been identified and tested. Some other research problems like enriching learning evolution chains with external data have been analyzed as well

    Preparation, Characterization And Performance Of Tio2 Based Catalytic Pellet For Detection Of Volatile Organic Compound Under UV Light[TP1-1185].

    Get PDF
    Dewasa ini, peraturan alam sekitar ke atas sebatian organik meruap telah diketatkan di seluruh dunia, memandangkan penyejatannya yang cepat dan beracun serta sifat karsinogenik semulajadinya pada kepekatan yang tinggi di dalam udara menyebabkan ia berbahaya kepada kehidupan manusia Nowadays, environmental regulations on volatile organic compounds (VOCs) have been tightened all over the world, as their rapid evaporation and toxic or carcinogenic nature at high concentrations in the air make them dangerous to human beings

    Symmetric bilinear forms and vertices in characteristic 2

    Get PDF
    Let GG be a finite group and let kk be an algebraically closed field of characteristic 22 and let MM be an indecomposable kGkG-module which affords a non-degenerate GG-invariant symmetric bilinear form. We introduce the symmetric vertices of MM. Each of these is a 22-subgroup of GG which contains a Green vertex of MM with index at most 22. If MM is irreducible then its symmetric vertices are determined up to GG-conjugacy. If BB is the real 22-block of GG containing MM, we show that each symmetric vertex of MM is contained in an extended defect group of BB. Moreover, we characterise the extended defect groups in terms of symmetric vertices. In order to prove these results, we develop the theory of involutary GG-algebras. This allows us to translate questions about symmetric kGkG-modules into questions about projective modules of quadratic type.Comment: Changes from v2: erroneous Lemma 2.3 (on lifting idempotents) corrected. Consequent minor changes made to the rest of the paper. Table of contents remove
    corecore