631 research outputs found
Thymidine phosphorylase in cancer cells stimulates human endothelial cell migration and invasion by the secretion of angiogenic factors
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].
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
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
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
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].
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
Let be a finite group and let be an algebraically closed field of
characteristic and let be an indecomposable -module which affords a
non-degenerate -invariant symmetric bilinear form. We introduce the
symmetric vertices of . Each of these is a -subgroup of which
contains a Green vertex of with index at most . If is irreducible
then its symmetric vertices are determined up to -conjugacy.
If is the real -block of containing , we show that each
symmetric vertex of is contained in an extended defect group of .
Moreover, we characterise the extended defect groups in terms of symmetric
vertices.
In order to prove these results, we develop the theory of involutary
-algebras. This allows us to translate questions about symmetric
-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
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