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The exudation of phenolics from the cut ends of mango explants greatly hinders their regenerative ability in any in vitro growth medium. However, pretreatment of explants using liquid shaker culture helps in overcoming this problem. Explants kept in liquid MS medium supplemented with 1% polyvinylpyrolidone in 250 ml conical flasks on an automated shaker at 75 rpm were able to produce shoots when inoculated on gelled MS medium supplemented with different concentrations of growth regulators.Abbreviations BA benzyladenine - IAA indoleacetic acid - NAA naphthaleneacetic acid - IBA indolebutyric acid  相似文献   
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Potentilla fulgens root traditionally used as a folk remedy in Meghalaya, India. However, systematic evaluation of its anticancer efficacy was limited. We investigated the anticancer potentials of the various extracts prepared by partitioning of the methanol extract of the root with the aim to discover major contributing factors from the most effective fractions. Methanol extract of P. fulgens roots (PRE) was prepared by maceration which was subsequently fractionated into hexane, ethyl-acetate (EA) and n-butanol soluble fractions. Various assays (clonogenic assay, Flow cytometry analysis, western blot, semiquantitative RT-PCR and the level of endogenous glutathione) were used to evaluate different parameters, such as Cell survivability, PARP-1 proteolysis, expression pattern of anti-apoptotic and γ-glutamyl-cysteine synthetase heavy subunit (GCSC) genes in both MCF-7 and U87 cancer cell lines. Since the EA-fraction showed most efficient growth inhibitory effect, it was further purified and a total of nine compounds and some monomeric and dimeric flavan-3-ols were identified and characterized. Three compounds viz., epicatechin (EC), gallic acid (GA) and ursolic acid (UA) were taken on the basis of their higher yield and 10 μg/ml of each was mixed together. The concentration used in this study for PRE, EA- and Hex-fraction was 100 μg/ml, which was higher than the IC50 value. Apoptotic cell death in the PRE, EA-fraction and EC+GA+UA treated cancer cell cultures was significantly greater than in normal cells due to suppression of anti-apoptotic protein Bcl2 following treatment. Depletion of glutathione by downregulating GCSC was also observed. Induction of apoptosis and lowering the level of glutathione are considered to be positive activity for an anticancer agent. Therefore, modulation of GSH concentration in tumor cells by PRE and its EA-fraction opened up the possibility of a new therapeutic approach because these plant products are not harmful to normal cells and may regulate the tumor cellular response to different anticancer treatments. Thus, it would be interesting to examine efficacy of these plant products or EA-fraction in human cancer treatment.  相似文献   
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Glycosylation is one of the most abundant and an important post-translational modification of proteins. Glycosylated proteins (glycoproteins) are involved in various cellular biological functions like protein folding, cell-cell interactions, cell recognition and host-pathogen interactions. A large number of eukaryotic glycoproteins also have therapeutic and potential technology applications. Therefore, characterization and analysis of glycosites (glycosylated residues) in these proteins is of great interest to biologists. In order to cater these needs a number of in silico tools have been developed over the years, however, a need to get even better prediction tools remains. Therefore, in this study we have developed a new webserver GlycoEP for more accurate prediction of N-linked, O-linked and C-linked glycosites in eukaryotic glycoproteins using two larger datasets, namely, standard and advanced datasets. In case of standard datasets no two glycosylated proteins are more similar than 40%; advanced datasets are highly non-redundant where no two glycosites’ patterns (as defined in methods) have more than 60% similarity. Further, based on our results with several algorihtms developed using different machine-learning techniques, we found Support Vector Machine (SVM) as optimum tool to develop glycosite prediction models. Accordingly, using our more stringent and non-redundant advanced datasets, the SVM based models developed in this study achieved a prediction accuracy of 84.26%, 86.87% and 91.43% with corresponding MCC of 0.54, 0.20 and 0.78, for N-, O- and C-linked glycosites, respectively. The best performing models trained on advanced datasets were then implemented as a user-friendly web server GlycoEP (http://www.imtech.res.in/raghava/glycoep/). Additionally, this server provides prediction models developed on standard datasets and allows users to scan sequons in input protein sequences.  相似文献   
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Lactation is a highly demanding event in mammals, including buffaloes. It modulates the partitioning of nutrients, energy utilization, and food intake of the mother to meet her own and infant's energy needs. Failure to satisfy these energy needs leads to Negative Energy Balance (NEB). Currently, the only available indirect NEB indicator is Body Condition Score (BCS). However, direct dependency of the BCS on the peak depletion of body fat causes its inefficient use in a dairy farm. Thus, to establish objective NEB indicators in buffaloes, the serum levels of biochemical (serum β-hydroxybutyrate [BHBA] and free fatty acids [FFAs]), and endocrine (Growth Hormone [GH], insulin-like growth factor1 [IGF1], Insulin, and leptin) parameters were estimated in buffaloes. Our results revealed that serum FFA levels were significantly (p < 0.05) higher in high milk yielders (HMY) than low milk yielders (LMY) and heifers (H) during the 3rd and the 4th weeks of postpartum. The serum FFA levels were also significantly (p < 0.001) higher in the postpartum buffaloes with BCS < 3 in the field conditions. Further, serum leptin levels were significantly (p < 0.05) lower in HMY than LMY during the 3rd week of postpartum. However, the BHBA, GH, IGF1, and insulin levels were not significantly different between lactating buffaloes and H. These observations indicated that the NEB condition is probably restricted to the first month of early lactation in buffaloes. In conclusion, the simultaneous higher FFA and lower leptin levels could act as direct plausible metabolic indicators of NEB in buffaloes.  相似文献   
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Response surface methodology (RSM) and centre composite design (CCD) were used to optimize immobilization of β-galactosidase (BGAL) from Pisum sativum onto two matrices: Sephadex G-75 and chitosan beads. The immobilization efficiency of 75.66% and 75.19% were achieved with Sephadex G-75 and chitosan, respectively. There was broad divergence in physico-chemical properties of Sephadex-PsBGAL and chitosan-PsBGAL. Chitosan-PsBGAL was better suited for industrial application based on its broad pH and temperature optima, higher temperature stability, reusability etc. Sephadex-PsBGAL and chitosan-PsBGAL showed much variation in their catalytic properties with respect to soluble enzyme. About 50% loss in activity of Sephadex-PsBGAL and chitosan-PsBGAL were observed after 12 and 46 days at 4 °C, respectively. Chitosan-PsBGAL showed higher rate of lactose hydrolysis present in milk and whey at room temperature and 4 °C than Sephadex-PsBGAL. In both cases, lactose of milk whey was hydrolyzed at higher rate than that of milk.  相似文献   
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Pseudomonas alcaligenes was detected at a high concentration (10 9 -10 10 cells mL -1 ) in the haemolymph of some dead Oryctes rhinoceros grubs collected from its breeding sites in the three southern districts, viz. Alleppey, Quilon and Kottayam of Kerala State, India. In a laboratory colony maintained for production of Oryctes virus, an important biocontrol agent of this major coconut pest, approximately 52% of the grubs succumbed to septicaemia with similar symptoms. The bacterium was found to be a component of the gut microflora of healthy grubs. Occurrence of the viral infection naturally or when induced in the laboratory in the O. rhinoceros grubs, appeared to be one of the biotic stress factors for P.alcaligenes to become an opportunistic pathogen. A preponderance of this bacterial infection in field populations during the periods when natural viral infection in grubs was above average, agrees with this observation. This finding becomes significant as infection by the opportunistic bacterial pathogen, P. alcaligenes , reduces the production of Oryctes virus inoculum in nature and limits the field-perpetuation of this viral biocontrol agent.  相似文献   
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