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991.
Gargi Maity Shabana Fahreen Aniruddha Banerji Paromita Roy Choudhury Triparna Sen Anindita Dutta Amitava Chatterjee 《Molecular and cellular biochemistry》2010,336(1-2):65-74
Interaction between cell surface integrin receptors and extracellular matrix (ECM) components plays an important role in cell survival, proliferation, and migration, including tumor development and invasion of tumor cells. Matrix metalloproteinases (MMPs) are a family of metalloproteinases capable of digesting ECM components and are important molecules for cell migration. Binding of ECM to integrins initiates cascades of cell signaling events modulating expression and activity of different MMPs. The aim of this study is to investigate fibronectin–integrin-mediated signaling and modulation of MMPs. Our findings indicated that culture of human cervical cancer cell (SiHa) on fibronectin-coated surface perhaps sends signals via fibronectin–integrin-mediated signaling pathways recruiting focal adhesion kinase (FAK) extracellular signal regulated kinase (ERK), phosphatidyl inositol 3 kinase (PI-3K), integrin-linked kinase (ILK), nuclear factor-kappa B (NF-κB), and modulates expression and activation of mainly pro-MMP-9, and moderately pro-MMP-2 in serum-free culture medium. 相似文献
992.
Fatouma Alimirah Avani Vaishnav Michael McCormick Ibtissam Echchgadda Bandana Chatterjee Rajendra G. Mehta Xinjian Peng 《Molecular and cellular biochemistry》2010,342(1-2):143-150
It is well-established that CYP24, an immediate target gene of VDR is upregulated by VDR ligands. This study is focused on the functional role of unliganded VDR by investigating the correlation between the expression of VDR protein and basal mRNA levels of CYP24 in breast cancer cell lines. Analyses of multiple breast cancer cell lines demonstrated an inverse correlation between VDR protein expression and CYP24 mRNA expression levels; while in the presence of ligand, VDR protein level was positively correlated with CYP24 expression. In MCF-7 cells, VDR was mainly distributed in the nuclei in the absence of ligand. VDR overexpression in MCF-7 cells and MDA-MB231 cells decreased CYP24 mRNA expression levels and CYP24 promoter activity. Conversely, knock-down of VDR using siRNA techniques in MCF-7 and T47D cells significantly increased CYP24 mRNA expression. We also found that overexpression of VDR with a polymorphic site (FokI-FF) at its AF-1 domain, which makes VDR shorter by three amino acids, failed to repress CYP24 promoter activity. This report provides conclusive evidence for the repressive action of unliganded VDR on the expression of its target gene CYP24 and the importance of an intact VDR AF-1 domain for its repressive action. 相似文献
993.
Hemang Parikh Zuoming Deng Meredith Yeager Joseph Boland Casey Matthews Jinping Jia Irene Collins Ariel White Laura Burdett Amy Hutchinson Liqun Qi Jennifer A. Bacior Victor Lonsberry Matthew J. Rodesch Jeffrey A. Jeddeloh Thomas J. Albert Heather A. Halvensleben Timothy T. Harkins Jiyoung Ahn Sonja I. Berndt Nilanjan Chatterjee Robert Hoover Gilles Thomas David J. Hunter Richard B. Hayes Stephen J. Chanock Laufey Amundadottir 《Human genetics》2010,127(1):91-99
Single nucleotide polymorphisms (SNPs) in the KLK3 gene on chromosome 19q13.33 are associated with serum prostate-specific antigen (PSA) levels. Recent genome wide association studies of prostate cancer have yielded conflicting results for association of the same SNPs with prostate cancer risk. Since the KLK3 gene encodes the PSA protein that forms the basis for a widely used screening test for prostate cancer, it is critical to fully characterize genetic variation in this region and assess its relationship with the risk of prostate cancer. We have conducted a next-generation sequence analysis in 78 individuals of European ancestry to characterize common (minor allele frequency, MAF >1%) genetic variation in a 56 kb region on chromosome 19q13.33 centered on the KLK3 gene (chr19:56,019,829–56,076,043 bps). We identified 555 polymorphic loci in the process including 116 novel SNPs and 182 novel insertion/deletion polymorphisms (indels). Based on tagging analysis, 144 loci are necessary to tag the region at an r 2 threshold of 0.8 and MAF of 1% or higher, while 86 loci are required to tag the region at an r 2 threshold of 0.8 and MAF >5%. Our sequence data augments coverage by 35 and 78% as compared to variants in dbSNP and HapMap, respectively. We observed six non-synonymous amino acid or frame shift changes in the KLK3 gene and three changes in each of the neighboring genes, KLK15 and KLK2. Our study has generated a detailed map of common genetic variation in the genomic region surrounding the KLK3 gene, which should be useful for fine-mapping the association signal as well as determining the contribution of this locus to prostate cancer risk and/or regulation of PSA expression. 相似文献
994.
Jayanta Chakrabarti Sabyasachi Chatterjee Sisir Ghosh Narayan Chandra Chatterjee Sikha Dutta 《Current microbiology》2010,61(3):203-209
A novel Acinetobacter strain, Ud-4, possessing a strong capacity to degrade edible, lubricating, and heavy oil was isolated from seawater in a
fishing port located in Toyama, Japan. It was identified by morphological and physiological analyses and 16S rDNA sequencing.
This strain could utilize five types of edible oils (canola oil, olive oil, sesame oil, soybean oil, and lard), lubricating
oil, and C-heavy oil as the sole carbon source for growth in M9 medium. The strain grew well and heavily degraded edible oils
in Luria–Bertani medium during a 7-day culture at 25°C; it also degraded all kinds of oils in artificial seawater medium for
marine bacteria. Furthermore, this strain was capable of degrading almost all C10–C25 n-alkanes in C-heavy oil during a 4-week culture. Oligonucleotide primers specific to two catabolic genes involved in the degradation
of n-alkanes (Acinetobacter sp. alkM) and triglyceride (Acinetobacter sp. lipA) allowed amplification of these genes in strain Ud-4. To our knowledge, this is the first report on the isolation of a bacterium
that can efficiently degrade both edible and mineral oils. 相似文献
995.
Chatterjee R Singh O Pachuau L Malik SP Paul M Bhadra K Paul S Kumar GS Mondal NB Banerjee S 《Bioorganic & medicinal chemistry letters》2010,20(22):6699-6702
Chromatographic separation of the methanolic extract of the leaves of Azadirachta indica led to the isolation of a sulfonoglycolipid characterized as a sulfonoquinovosyldiacylglyceride (SQDG), by extensive 2D NMR and mass spectral analysis. SQDG induces apoptosis in a dose dependent manner with IC(50) 8.3 μM against acute lymphoblastic leukemia (ALL) MOLT-4 cell lines. The compound showed significant DNA binding properties as evidenced by the enhancement of melting temperature and perturbation of the characteristic B-form in CD evidence of calf thymus DNA. The DNA binding was also characterized by isothermal calorimetry where a predominantly enthalpy driven binding to CT DNA was revealed. 相似文献
996.
Goyal AK Middha SK Usha T Chatterjee S Bothra AK Nagaveni MB Sen A 《Bioinformation》2010,5(4):184-185
Bamboo, the "Green Gold", included in the non-timber forest products has both ecological and economic importance. Here is an attempt to describe a database named "Bambooinfoline" , which provides enumeration of the different species of bamboos found in North Bengal, with special emphasis on taxonomy, edible properties, chemical constituents, morphological features along with tissue culture specifications, which in turn benefits of scientific community. AVAILABILITY: The database is freely available at http://www.bamboodb.ind.in/ 相似文献
997.
Nilanjan Chatterjee 《Biometrics》2003,59(4):1184-1185
998.
The unique physicochemical properties of a thioamide bond, which is an ideal isostere of an amide bond, have not been fully exploited because of the tedious synthesis of thionated amino acid building blocks. Here, we report a purification‐free and highly efficient synthesis of thiobenzotriazolides of Fmoc‐protected and orthogonally protected 20 naturally occurring amino acids including asparagine, glutamine, and histidine. The near‐quantitative conversion to the respective thioamidated peptides on solid support demonstrates the robustness of the synthetic route. Furthermore, the unaltered incorporation efficiency of thiobenzotriazolides from their stock solution till 48 h suggests their compatibility toward automated peptide synthesis. Finally, utilizing an optimized cocktail of 2% DBU + 5% piperazine for fast Fmoc‐deprotection, we report the synthesis of a thioamidated Pin1 WW domain and thioamidated GB1 directly on solid support. 相似文献
999.
Sumit Ranjan Sahu Vallabha Rao Rikka Prathap Haridoss Abhijit Chatterjee Raghavan Gopalan Raju Prakash 《Liver Transplantation》2020,10(36)
Orthorhombic α‐MoO3 is a potential anode material for lithium‐ion batteries due to its high theoretical capacity of 1100 mAh g?1 and excellent structural stability. However, its intrinsic poor electronic conductivity and high volume expansion during the charge–discharge process impede it from achieving a high practical capacity. A novel composite of α‐MoO3 nanobelts and single‐walled carbon nanohorns (SWCNHs) is synthesized by a facile microwave hydrothermal technique and demonstrated as a high‐performance anode material for lithium‐ion batteries. The α‐MoO3/SWCNH composite displays superior electrochemical properties (654 mAh g?1 at 1 C), excellent rate capability (275 mAh g?1 at 5 C), and outstanding cycle life (capacity retention of >99% after 3000 cycles at 1 C) without any cracking of the electrode. The presence of SWCNHs in the composite enhances the electrochemical properties of α‐MoO3 by acting as a lithium storage material, electronic conductive medium, and buffer against pulverization. 相似文献
1000.
Samrat Paul Piyali Basak Ranabir Majumder Anwesha Mukherjee Joydeep Ghosh Shamayita Patra Nandan Kumar Jana 《Journal of plant biochemistry and biotechnology.》2020,29(1):86-93
Breast tissue remodeling occurs throughout a women’s life from pre-menstrual to post menopausal time, hence there is a high risk of DNA damage. Estrogen metabolite generates free radical that causes DNA damage leading to cancer cell formation. Moringa oleifera leaf extract contain rich amount of Polyphenolic and Flavonoids compound which trap the free radical and thereby prevent cancer cell progression. Moreover anti-gonadotrophic hormonal activity of the leaf extract slows down the proliferation rate of T47D cell line. Hence our aim of study mainly focused to develop an anticancer drug delivery system using M. oleifera leaf extract. Silver nanoparticle (AgNp) is formed by green synthesis method using M. oleifera leaf extract. Reducing sugar, Flavonoids, Polyphenolic compound, and NADPH dependent dehydrogenase present in M. oleifera leaf extract are responsible for reduction of the silver ion (Ag+) followed by formation of metallic silver (Ag0). The formation of spherical and rectangular shaped AgNp with average size of 50 nm is reflected with sharp SPR band near 420 nm and from SEM, TEM analysis. The nanoparticle mediated polyvinyl alcohol composite film (nano-rod) is prepared for delivery of the purified anti-neoplastic phyto-compound from leaf extract. The large surface area of AgNp permits its coordination with purified compound molecule by metal ligand bonding. Therefore it provide duel effect, it acts as carrier molecule for phyto-compound and also creates cytotoxicity effect on cancer cells. Single dose treatment on HeLa cell indicates that the composite film is more effective in killing the cancer cell than the purified anti-neoplastic phyto-compound. 相似文献