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91.
Cation-aromatic database   总被引:1,自引:0,他引:1  
Reddy AS  Sastry GM  Sastry GN 《Proteins》2007,67(4):1179-1184
Cation-aromatic database (CAD) is a publicly available web-based database that aims to provide further understanding of interaction between a cation and the pi interactions. A tool to identify the interactions in a user-given protein is also added to the database. CAD is freely accessible via the Internet at http://203.199.182.73/gnsmmg/databases/cad/.  相似文献   
92.
Molecular and Cellular Biochemistry - The nicotinamide adenine dinucleotide (NAD+) is an essential redox cofactor, involved in various physiological and molecular processes, including energy...  相似文献   
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94.
During development, the growth of the embryo must be coupled to its patterning to ensure correct and timely morphogenesis. In the mouse embryo, migration of the anterior visceral endoderm (AVE) to the prospective anterior establishes the anterior-posterior (A-P) axis. By analysing the distribution of cells in S phase, M phase and G2 from the time just prior to the migration of the AVE until 18 hours after its movement, we show that there is no evidence for differential proliferation along the A-P axis of the mouse embryo. Rather, we have identified that as AVE movements are being initiated, the epiblast proliferates at a much higher rate than the visceral endoderm. We show that these high levels of proliferation in the epiblast are dependent on Nodal signalling and are required for A-P establishment, as blocking cell division in the epiblast inhibits AVE migration. Interestingly, inhibition of migration by blocking proliferation can be rescued by Dkk1. This suggests that the high levels of epiblast proliferation function to move the prospective AVE away from signals that are inhibitory to its migration. The finding that initiation of AVE movements requires a certain level of proliferation in the epiblast provides a mechanism whereby A-P axis development is coordinated with embryonic growth.  相似文献   
95.
A thorough and extensive wild germplasm exploration survey was undertaken and 50 high yielding candidate plus trees (CPTs) of Pongamia pinnata (L.) Pierre from different locations from a latitudinal and longitudinal spread between 12°41′ and 22°E longitude and 77° and 84°40′N latitude covering 11 locations in an area spread of 150,000 km2 were collected for evaluating genetic association and variability in seed and growth characters. There were significant differences observed in seed morphology and oil content as was in plant height, and number of branches in the progeny trial. Plant height and number of branches exhibited much higher values of both phenotypic and genotypic variance than observed in the seed characters. Among seed characters oil content exhibited highest broad sense heritability of more than 93% followed by seed length (90.0%). In contrast seed width showed the second highest genetic advance of 5.64% following the highest genetic advance of 10.15% exhibited by oil content. Hierarchical clustering by Ward’s Minimum Variance Cluster Analysis method showed phylogeographic patterns of genetic diversity. K means clustering revealed that trees from different geographic regions were grouped together in a cluster and as were trees from the same geographical area placed in different clusters suggesting that geographical diversity did not go hand in hand with genetic diversity. In addition clustering identified promising accessions with favourable traits for future establishment of orchards.  相似文献   
96.
HIV-1 integrase (IN) is a validated therapeutic target for antiviral drug design. However, the emergence of viral strains resistant to clinically studied IN inhibitors demands the discovery of novel inhibitors that are structurally as well mechanistically different. Herein, we describe the design and discovery of novel IN inhibitors targeting the catalytic domain as well as its interaction with LEDGF/p75, which is essential for the HIV-1 integration as an IN cofactor. By merging the pharmacophores of salicylate and catechol, the 2,3-dihydroxybenzamide (5a) was identified as a new scaffold to inhibit the strand transfer reaction efficiently. Further structural modifications on the 2,3-dihydroxybenzamide scaffold revealed that the heteroaromatic functionality attached on the carboxamide portion and the piperidin-1-ylsulfonyl substituted at the phenyl ring are beneficial for the activity, resulting in a low micromolar IN inhibitor (5p, IC(50)=5 μM) with more than 40-fold selectivity for the strand transfer over the 3'-processing reaction. More significantly, this active scaffold remarkably inhibited the interaction between IN and LEDGF/p75 cofactor. The prototype example, N-(cyclohexylmethyl)-2,3-dihydroxy-5-(piperidin-1-ylsulfonyl) benzamide (5u) inhibited the IN-LEDGF/p75 interaction with an IC(50) value of 8 μM. Using molecular modeling, the mechanism of action was hypothesized to involve the chelation of the divalent metal ions inside the IN active site. Furthermore, the inhibitor of IN-LEDGF/p75 interaction was properly bound to the LEDGF/p75 binding site on IN. This work provides a new and efficient approach to evolve novel HIV-1 IN inhibitors from rational integration and optimization of previously reported inhibitors.  相似文献   
97.
Three 16S rRNA gene clone libraries (P1L, P4L and P8L) were constructed using three soil samples (P1S, P4S and P8S) collected near Pindari glacier, Himalayas. The three libraries yielded a total of 703 clones. Actinobacteria, Firmicutes and Proteobacteria were common to the three libraries. In addition to the above P1L and P8L shared the phyla Acidobacteria, Bacteroidetes, Gemmatimonadetes and Planctomycetes. Phyla Chlamydiae, Chlorobi, Chloroflexi, Dictyoglomi, Fibrobacteres, Nitrospirae, Verrucomicrobia, candidate division SPAM and candidate TM7s TM7a phylum were present only in P1L. Rarefaction analysis indicated that the bacterial diversity in P4S and P8S soil samples was representative of the sample. Principal component analysis (PCA) revealed that P1S and P8S were different from P4S soil sample. PCA also indicated that arsenic content, pH, Cr and altitude influence the observed differences in the percentage of specific OTUs in the three 16S rRNA gene clone libraries. The observed bacterial diversity was similar to that observed for other Himalayan and non-polar cold habitats. A total of 40 strains of bacteria were isolated from the above three soil samples and based on the morphology 20 bacterial strains were selected for further characterization. The 20 bacteria belonged to 12 different genera. All the isolates were psychro-, halo- and alkalitolerant. Amylase and urease activities were detected in majority of the strains but lipase and protease activities were not detected. Long chain, saturated, unsaturated and branched fatty acids were predominant in the psychrotolerant bacteria.  相似文献   
98.

Background

Effective provider-parent communication can improve childhood vaccination uptake and strengthen immunisation services in low- and middle-income countries (LMICs). Building capacity to improve communication strategies has been neglected. Rigorous research exists but is not readily found or applicable to LMICs, making it difficult for policy makers to use it to inform vaccination policies and practice. The aim of this project is to build research knowledge and capacity to use evidence-based strategies for improving communication about childhood vaccinations with parents and communities in LMICs.

Methods and design

This project is a mixed methods study with six sub-studies. In sub-study one, we will develop a systematic map of provider-parent communication interventions for childhood vaccinations by screening and extracting data from relevant literature. This map will inform sub-study two, in which we will develop a taxonomy of interventions to improve provider-parent communication around childhood vaccination. In sub-study three, the taxonomy will be populated with trial citations to create an evidence map, which will also identify how evidence is linked to communication barriers regarding vaccination. In the project's fourth sub-study, we will present the interventions map, taxonomy, and evidence map to international stakeholders to identify high-priority topics for systematic reviews of interventions to improve parent-provider communication for childhood vaccination. We will produce systematic reviews of the effects of high-priority interventions in the fifth sub-study. In the sixth and final sub-study of the project, evidence from the systematic reviews will be translated into accessible formats and messages for dissemination to LMICs.

Discussion

This project combines evidence mapping, conceptual and taxonomy development, priority setting, systematic reviews, and knowledge transfer. It will build and share concepts, terms, evidence, and resources to aid the development of communication strategies for effective vaccination programmes in LMICs.  相似文献   
99.
Our previous studies have shown that benzyl isothiocyanate (BITC) suppresses pancreatic tumor growth by inhibiting STAT-3; however, the exact mechanism of tumor growth suppression was not clear. Here we evaluated the effects and mechanism of BITC on pancreatic tumor angiogenesis. Our results reveal that BITC significantly inhibits neovasularization on rat aorta and Chicken-Chorioallantoic membrane. Furthermore, BITC blocks the migration and invasion of BxPC-3 and PanC-1 pancreatic cancer cells in a dose dependant manner. Moreover, secretion of VEGF and MMP-2 in normoxic and hypoxic BxPC-3 and PanC-1 cells was significantly suppressed by BITC. Both VEGF and MMP-2 play a critical role in angiogenesis and metastasis. Our results reveal that BITC significantly suppresses the phosphorylation of VEGFR-2 (Tyr-1175), and expression of HIF-α. Rho-GTPases, which are regulated by VEGF play a crucial role in pancreatic cancer progression. BITC treatment reduced the expression of RhoC whereas up-regulated the expression of tumor suppressor RhoB. STAT-3 over-expression or IL-6 treatment significantly induced HIF-1α and VEGF expression; however, BITC substantially suppressed STAT-3 as well as STAT-3-induced HIF-1α and VEGF expression. Finally, in vivo tumor growth and matrigel-plug assay show reduced tumor growth and substantial reduction of hemoglobin content in the matrigel plugs and tumors of mice treated orally with 12 μmol BITC, indicating reduced tumor angiogenesis. Immunoblotting of BITC treated tumors show reduced expression of STAT-3 phosphorylation (Tyr-705), HIF-α, VEGFR-2, VEGF, MMP-2, CD31 and RhoC. Taken together, our results suggest that BITC suppresses pancreatic tumor growth by inhibiting tumor angiogenesis through STAT-3-dependant pathway.  相似文献   
100.
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