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501.
Subhas S. Karki Vivek Singh Bahaduria Vivek Rana Sujeet Kumar Prasanna G. Subbaro Umashankar Das 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):537-544
Various substituted 1-arylmethyl-2,3-dioxo-2,3-dihydroindole thiosemicarbazones 3a-h, 1-benzyl-2,3-dioxo-2,3-dihydroindole N4-aryl thiosemicarbazones 4a-i and 1-benzyl-2,3-dioxy-2,3-dihydroindole N4-cyclohexylthiocarbazone 5 were synthesized. All of these compounds were evaluated against human Molt 4/C8 and CEM T-lymphocytes as well as murine L1210 leukemia cells. Nearly 40% of these compounds possess low micromolar IC50 values and some are either more potent than, or equipotent with, melphalan. Various correlations between the structures of these compounds and cytotoxic potencies were obtained which included the use of QSAR and molecular modeling techniques. Representative compounds displayed anticonvulsant properties in rats and were well tolerated by these animals. The encouraging biodata noted affords adequate rationale for outlining guidelines for further development of these molecular scaffolds. 相似文献
502.
503.
Hanumanthu Prasanna Lakshmi Sthanikam Yeswanth Uppu Venkateswara Prasad Dudipeta Vasu Vimjam Swarupa Pasupuleti Santhosh Kumar Mangamoori Lakshmi Narasu Potukuchi Venkata Gurunadha Krishna Sarma 《Bioinformation》2013,9(4):169-173
Glucose-6-phosphate (G-6-P) formation in Staphylococcus aureus is catalysed by glucokinase (glkA) gene under high glucose
concentration leading to upregulation of various pathogenic factors; therefore the present study is aimed in the cloning and
characterization of glk A gene from S. aureus ATCC12600. The glk A gene was cloned in the Sma I site of pQE 30, sequenced
(Accession number: ) and expressed in E. coli DH5α. The recombinant glk A expressed from the resultant glk A 1 clone
was purified using nickel metal chelate chromatography, the pure enzyme gave single band in SDS-PAGE with molecular weight
of 33kDa. The rglk A showed very high affinity to glucose Km 5.1±0.06mM with Hill coefficient of 1.66±0.032mM. Analysis of
glucokinase sequence of S. aureus showed presence of typical ATP binding site and ROK motif CNCGRSGCIE. Sequentially and
phylogenetically S. aureus glk A exhibited low identity with other bacterial glk A and 21% homology with human glucokinase
(GCK). Functionally, S. aureus glk A showed higher rate of G-6-P formation compared to human GCK which may have profound
role in the pathogenesis. JN645812相似文献
504.
Feature selection from DNA microarray data is a major challenge due to high dimensionality in expression data. The number of
samples in the microarray data set is much smaller compared to the number of genes. Hence the data is improper to be used as the
training set of a classifier. Therefore it is important to select features prior to training the classifier. It should be noted that only a
small subset of genes from the data set exhibits a strong correlation with the class. This is because finding the relevant genes from
the data set is often non-trivial. Thus there is a need to develop robust yet reliable methods for gene finding in expression data. We
describe the use of several hybrid feature selection approaches for gene finding in expression data. These approaches include
filtering (filter out the best genes from the data set) and wrapper (best subset of genes from the data set) phases. The methods use
information gain (IG) and Pearson Product Moment Correlation (PPMC) as the filtering parameters and biogeography based
optimization (BBO) as the wrapper approach. K nearest neighbour algorithm (KNN) and back propagation neural network are
used for evaluating the fitness of gene subsets during feature selection. Our analysis shows that an impressive performance is
provided by the IG-BBO-KNN combination in different data sets with high accuracy (>90%) and low error rate. 相似文献
505.
Our current understanding of clathrin-mediated endocytosis proposes that the process is initiated at a specialized anatomical structure called a coated pit. Electron microscopy has been required for elucidation of the morphology of coated pits and the vesicles produced therein, and the presence of a bristle coat has been taken as suggestive of clathrin surrounding these vesicles. More recently, immunocytochemical methods have confirmed that endocytic vesicles are surrounded by clathrin and its adaptor proteins, but there is a need to identify precisely and to follow the fate of the cellular organelles seen by fluorescence microscopy. We used quantum immune-electron microscopy to localize clathrin in a human adrenal cortical cell line (SW-13). Clathrin was shown to associate with a variety of vesicle types including the classic clathrin-coated vesicles and pits used in receptor internalization, pentilaminar annular gap junction vesicles, and multivesicular bodies. The images obtained with quantum dot technology allow accurate and specific localization of clathrin and the clathrin adaptor protein, AP-2, with cellular organelles and suggest that some of the structures classified as typical coated vesicles by immunocytochemical light microscopic techniques actually may be membrane bound pits. 相似文献
506.
Buddhika TB Wijerathne Geetha K Rathnayake Shamila C Adikari Subashini Amarasinghe Prasanna L Abhayarathna Ajith S Jayasena 《Journal of physiological anthropology》2013,32(1):27
Background
The purpose of this study was to evaluate gender-wise diversity of digital dermatoglyphic traits in a sample of Sinhalese people in Sri Lanka.Findings
Four thousand and thirty-four digital prints of 434 Sinhalese individuals (217 males and 217 females) were examined for their digital dermatoglyphic pattern distribution. The mean age for the entire group was 23.66 years (standard deviation = 4.93 years). The loop pattern is observed more frequently (n = 2,592, 59.72%) compared to whorl (n = 1,542, 35.53%) and arch (n = 206, 4.75%) in the Sinhalese population. Females (n = 1,274, 58.71%) have a more ulnar loop pattern than males (n = 1,231, 56.73%). The plain whorl pattern is observed more frequently in males (n = 560, 25.81%) compared to females (n = 514, 23.69%).The double loop pattern is observed more frequently on the right and left thumb (digit 1) of both males and females. Pattern intensity index, Dankmeijer index and Furuhata index are higher in males.Conclusions
Ulnar loop is the most frequently occurring digital dermatoglyphic pattern among the Sinhalese. All pattern indices are higher in males. To some extent, dermatoglyphic patterns of Sinhalese are similar to North Indians and other Caucasoid populations. Further studies with larger sample sizes are recommended to confirm our findings. 相似文献507.
508.
This study uses a reconstructed vascular geometry to evaluate the thermal response of tissue during a three-dimensional radiofrequency (rf) tumor ablation. MRI images of a sectioned liver tissue containing arterial vessels are processed and converted into a finite-element mesh. A rf heat source in the form of a spherically symmetric Gaussian distribution, fit from a previously computed profile, is employed. Convective cooling within large blood vessels is treated using direct physical modeling of the heat and momentum transfer within the vessel. Calculations of temperature rise and thermal dose are performed for transient rf procedures in cases where the tumor is located at three different locations near the bifurcation point of a reconstructed artery. Results demonstrate a significant dependence of tissue temperature profile on the reconstructed vasculature and the tumor location. Heat convection through the arteries reduced the steady-state temperature rise, relative to the no-flow case, by up to 70% in the targeted volume. Blood flow also reduced the thermal dose value, which quantifies the extent of cell damage, from approximately 3600 min, for the no-flow condition, to 10 min for basal flow (13.8 cms). Reduction of thermal dose below the threshold value of 240 min indicates ablation procedures that may inadequately elevate the temperature in some regions, thereby permitting possible tumor recursion. These variations are caused by vasculature tortuosity that are patient specific and can be captured only by the reconstruction of the realistic geometry. 相似文献
509.
Raphael BM Aggio Arno Mayor Sophie Reade Chris SJ Probert Katya Ruggiero 《BMC bioinformatics》2014,15(1)