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981.
Several molecular and cellular markers are currently used as prognostic indicators for diagnosis and therapeutic intervention of breast cancer. Although some of these markers have helped clinicians provide an earlier diagnosis (or prognosis), they have failed to provide adequate information about the mechanisms responsible for different stages of tumor malignancy so that more effective anticancer therapies can be developed. Recently translocator protein (TSPO), formerly known as the peripheral benzodiazepine receptor (PBR), has received attention as a potential target for anticancer drug development. It is a well-conserved protein, located at outer-inner mitochondrial membrane contact sites, and is expressed in almost all tissues, although the level of expression varies. TSPO is closely associated with the 32 kDa voltage-dependent anion channel (VDAC) and the 30 kDa adenine nucleotide translocase (ANT), considered to form the core of a mitochondria multiprotein complex [named the mitochondrial permeability transition pore (MPTP)] and plays a role in apoptotic cell death. As the major role of TSPO is steroid biosynthesis, TSPO expression is particularly high in organs involved in steroidogenesis such as the adrenals, testes, ovaries, placenta, prostate, colon, kidney, and cardiovascular system. It is well known that TSPO is over-expressed in highly aggressive tumors, especially those of the breast, and that expression correlates with advancing stages of this malignancy. TSPO expression, nuclear localization, and TSPO-mediated cholesterol transport into the nucleus are involved in breast cancer cell proliferation and aggressive phenotype expression. Hence, it can be used as a biomarker in the stage-dependent diagnosis of this cancer. In addition, cell proliferation, invasion and migration appears to be decreased when treated with high doses of TSPO ligand PK-11195, a compound that may represent a therapeutic agent for the control of breast cancer progression. Control of breast cancer development by consumption of dietary soy protein has been linked to down-regulation of the expression of TSPO-mediated angiogenic signaling molecules. This chapter provides insight into the potential of TSPO as a rational target for the development of novel therapeutics for breast cancer. 相似文献
982.
Amrita Banerjee Arijit Jana Bikash R. Pati Keshab C. Mondal Pradeep K. Das Mohapatra 《The protein journal》2012,31(4):306-327
The tannase protein sequences of 149 bacteria and 36 fungi were retrieved from NCBI database. Among them only 77 bacterial
and 31 fungal tannase sequences were taken which have different amino acid compositions. These sequences were analysed for
different physical and chemical properties, superfamily search, multiple sequence alignment, phylogenetic tree construction
and motif finding to find out the functional motif and the evolutionary relationship among them. The superfamily search for
these tannase exposed the occurrence of proline iminopeptidase-like, biotin biosynthesis protein BioH, O-acetyltransferase,
carboxylesterase/thioesterase 1, carbon–carbon bond hydrolase, haloperoxidase, prolyl oligopeptidase, C-terminal domain and
mycobacterial antigens families and alpha/beta hydrolase superfamily. Some bacterial and fungal sequence showed similarity
with different families individually. The multiple sequence alignment of these tannase protein sequences showed conserved
regions at different stretches with maximum homology from amino acid residues 389–469 and 482–523 which could be used for
designing degenerate primers or probes specific for tannase producing bacterial and fungal species. Phylogenetic tree showed
two different clusters; one has only bacteria and another have both fungi and bacteria showing some relationship between these
different genera. Although in second cluster near about all fungal species were found together in a corner which indicates
the sequence level similarity among fungal genera. The distributions of fourteen motifs analysis revealed Motif 1 with a signature
amino acid sequence of 29 amino acids, i.e. GCSTGGREALKQAQRWPHDYDGIIANNPA, was uniformly observed in 83.3 % of studied tannase
sequences representing its participation with the structure and enzymatic function. 相似文献
983.
Zhu W Frost EE Begum F Vora P Au K Gong Y MacNeil B Pillai P Namaka M 《Journal of cellular and molecular medicine》2012,16(8):1856-1865
Multiple sclerosis (MS) is characterized by focal destruction of the white matter of the brain and spinal cord. The exact mechanisms underlying the pathophysiology of the disease are unknown. Many studies have shown that MS is predominantly an autoimmune disease with an inflammatory phase followed by a demyelinating phase. Recent studies alongside current treatment strategies, including glatiramer acetate, have revealed a potential role for brain-derived neurotrophic factor (BDNF) in MS. However, the exact role of BDNF is not fully understood. We used the experimental autoimmune encephalomyelitis (EAE) model of MS in adolescent female Lewis rats to identify the role of BDNF in disease progression. Dorsal root ganglia (DRG) and spinal cords were harvested for protein and gene expression analysis every 3 days post-disease induction (pdi) up to 15 days. We show significant increases in BDNF protein and gene expression in the DRG of EAE animals at 12 dpi, which correlates with peak neurological disability. BDNF protein expression in the spinal cord was significantly increased at 12 dpi, and maintained at 15 dpi. However, there was no significant change in mRNA levels. We show evidence for the anterograde transport of BDNF protein from the DRG to the dorsal horn of the spinal cord via the dorsal roots. Increased levels of BDNF within the DRG and spinal cord in EAE may facilitate myelin repair and neuroprotection in the CNS. The anterograde transport of DRG-derived BDNF to the spinal cord may have potential implications in facilitating central myelin repair and neuroprotection. 相似文献
984.
985.
986.
Q. Chen D. Das D. Chitnis K. Walls T. D. Drysdale S. Collins D. R. S. Cumming 《Plasmonics (Norwell, Mass.)》2012,7(4):695-699
Multi-pixel, 4.5?×?9???m, plasmonic colour filters, consisting of periodic subwavelength holes in an aluminium film, were directly integrated on the top surface of a complementary metal oxide semiconductor (CMOS) image sensor (CIS) using electron beam lithography and dry etch. The 100?×?100-pixel plasmonic CIS showed full colour sensitivities across the visible range determined by a photocurrent measurement. The filters were fabricated in a simple process utilising a single lithography step. This is to be compared with the traditional multi-step processing when using dye-doped polymers. The intrinsic compatibility of these plasmonic components with a standard CMOS process allows them to be manufactured in a metal layer close to the photodiodes. The incorporation of such plasmonic components may in the future enable the development of advanced CIS with low cost, low cross-talk and increased functionality. 相似文献
987.
Nowadays gold nanoparticle (GNP) is increasingly being used in drug delivery and diagnostics. Here we have reported a comparative analysis of detailed stability and toxicity (in vitro and in vivo) profile of three water soluble spherical GNPs, having nearly similar size, but the surfaces of which were modified with three different capping materials aspartic acid (GNPA), trisodium citrate dihydrate (GNPC) or bovine serum albumin (GNPB). Spectral analyses on the stability of these GNPs revealed that depending on the nature of capping agents, GNPs behave differently at different environmental modalities like wide range of pH, high salt concentrations, or in solutions and buffers of biological usage. GNPB was found to be extremely stable, where capped protein molecule successfully maintained its secondary structure and helicity on the nanoparticle, whereas colloidal stability of GNPA was most susceptible to altered conditions. In vitro cytotoxicity of these nanoparticle formulations in vitro were determined by water soluble tetrazolium and lactate dehydrogenase assay in human fibroblast cell line (MRC-5) and acute oral toxicity was performed in murine model system. All the GNPs were non-toxic to MRC-5 cells. GNPC had slight hepatotoxic and nephrotoxic responses. Hepatotoxicity was also evident for GNPA treatment. Present study established that there is a correlation between capping material and stability together with toxicity of nanoparticles. GNPB was found to be most biocompatible among the three GNPs tested. 相似文献
988.
Rahul R Nair Manivasagam B Nandhini Elango Monalisha Kavitha Murugan Thilaga Sethuraman Sangeetha Nagarajan Nayani Surya Prakash Rao Doss Ganesh 《Bioinformation》2012,8(22):1096-1104
Synonymous codon usage of 53 protein coding genes in chloroplast genome of Coffea arabica was analyzed for the first time to find
out the possible factors contributing codon bias. All preferred synonymous codons were found to use A/T ending codons as
chloroplast genomes are rich in AT. No difference in preference for preferred codons was observed in any of the two strands, viz.,
leading and lagging strands. Complex correlations between total base compositions (A, T, G, C, GC) and silent base contents (A3, T3,
G3, C3, GC3) revealed that compositional constraints played crucial role in shaping the codon usage pattern of C. arabica chloroplast
genome. ENC Vs GC3 plot grouped majority of the analyzed genes on or just below the left side of the expected GC3 curve
indicating the influence of base compositional constraints in regulating codon usage. But some of the genes lie distantly below the
continuous curve confirmed the influence of some other factors on the codon usage across those genes. Influence of compositional
constraints was further confirmed by correspondence analysis as axis 1 and 3 had significant correlations with silent base contents.
Correlation of ENC with axis 1, 4 and CAI with 1, 2 prognosticated the minor influence of selection in nature but exact separation
of highly and lowly expressed genes could not be seen. From the present study, we concluded that mutational pressure combined
with weak selection influenced the pattern of synonymous codon usage across the genes in the chloroplast genomes of C. arabica. 相似文献
989.
Abhishek Chowdhury Shantanu Sen Pradip Dey Pankaj Chetia Anupam Das Talukdar Amitabha Bhattacharjee Manabendra Dutta Choudhury 《Bioinformation》2012,8(18):875-880
The advent of Multi Drug Resistant (MDR) strain of Mycobacterium tuberculosis (TB) necessitated search for new drug targets for the
bacterium. It is reported that 3.3% of all new tuberculosis cases had multidrug resistance (MDR-TB) in 2009 and each year, about
0.44 million MDR-TB cases are estimated to emerge and 0.15 million people with MDR-TB die. Keeping such an alarming situation
under consideration we wanted to design suitable anti tubercular molecules for new target using computational tools. In the work
Methionine aminopeptidase (MetAP) of Mycobacterium tuberculosis was considered as target and three non-toxic phenolic=ketonic
compounds were considered as ligands. Docking was done with Flex X and AutoDock 4.2 separately. Ten proven inhibitors of
MetAP were collected from literature with their IC50 and were correlated using EasyQSAR to generate QSAR model. Activity of
ligands in question was predicted from QSAR. Pharmacophore for each docking was generated using Ligandscout 3.0. Toxicity of
the ligands in question was predicted on Mobyle@rpbs portal and Actelion property explorer. Molecular docking with target
showed that of all three ligands, 3-ammonio-3-(4-oxido-1H-imidazol-1-ium-5-yl) propane-1, 1-bis (olate) has highest affinity (-
37.5096) and lowest IC50 (4.46 µM). We therefore, propose that -3-ammonio-3-(4-oxido-1H-imidazol-1-ium-5-yl) propane-1,1-
bis(olate) as a potent MetAP inhibitor may be a new anti-tubercular drug particularly in the context of Multi Drug Resistant
Tuberculosis (MDR-TB). 相似文献
990.
There are over 600 million people worldwide covering Asian and Oceanic countries including India have the habit of chewing areca nut as masticator in different forms. Arecoline (C(8)H(13)NO(2)) has been reported as one of the abundant constituents of areca nut. A good number of scientific publications have made Arecoline responsible for oral cancer. Based on observation from clinical situation in North East India, one of the most betel quid chewing region of the country, we suspected a link between consumption of areca nut and Cerebro Vascular Disease like stroke. Therefore, we considered Low Density Lipoprotein (LDL) receptor as target and Arecoline as ligand and studied ligand -target interaction using computational tools. Also we considered High Density Lipoprotein (HDL) receptor as another target to see if Arecoline has any binding potential with it over and above LDL receptor. Docking result indicated that Arecoline and Cholesterol both, have affinity towards extracellular domain of Human LDL receptor but affinity of Arecoline is much higher (-12.3560.) than that of Cholesterol(-0.1810). Docking of Arecoline and 1, 2-Hexyl-1- cyclopentanone thiosemicarbazone (thiosemicarbazone) with Bovine HDL receptor showed that Arecoline also has the potential (Score, -6.2690Kcal/Mol) to block HDL receptor though its potential is less than that (score, -10.0509 Kcal/Mol) of control (thiosemicarbazone). We, therefore, suggest that by inhibiting endocytosis of LDL cholesterol because of blocking LDL receptor function and also by preventing LDL cholesterol uptake by liver from blood because of interference with HDL receptor, Arecoline may contribute to atherosclerosis. The study therefore, indicates a positive correlation between chewing of betel quid and Cerebro Vascular Disease. 相似文献