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21.
Plasmonics - In this study, we report a design concept to obtain center frequency and bandwidth reconfigurable spoof surface plasmon polaritons (SSPP) band-pass filter using T-shaped spoof SPP...  相似文献   
22.

RNA interference (RNAi)-based host-induced gene silencing (HIGS) is emerging as a novel, efficient and target-specific tool to combat phytonematode infection in crop plants. Mi-msp-1, an effector gene expressed in the subventral pharyngeal gland cells of Meloidogyne incognita plays an important role in the parasitic process. Mi-msp-1 effector is conserved in few of the species of root-knot nematodes (RKNs) and does not share considerable homology with the other phytonematodes, thereby making it a suitable target for HIGS with minimal off-target effects. Six putative eggplant transformants harbouring a single copy RNAi transgene of Mi-msp-1 was generated. Stable expression of the transgene was detected in T1, T2 and T3 transgenic lines for which a detrimental effect on RKN penetration, development and reproduction was documented upon challenge infection with nematode juveniles. The post-parasitic nematode stages extracted from the transgenic plants showed long-term RNAi effect in terms of targeted downregulation of Mi-msp-1. These findings suggest that HIGS of Mi-msp-1 enhances nematode resistance in eggplant and protect the plant against RKN parasitism at very early stage.

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23.
DNA-enzymes (Dzs) usually cleave short synthetic target RNAs very efficiently, but this activity diminishes significantly when tested on full-length RNAs, primarily because of the rigid secondary structures near the target sequence. We identified two Dzs, one each for 81-17 and 10-23 Dz, which cleaved the human immunodeficiency virus type 1 (HIV-1) Gag RNA poorly. We sought to use short oligodeoxynucleotides (ODNs) with the hope that it will facilitate Dz-mediated cleavage. The efficiencies of several ODNs were analyzed for their ability to augment the 8-17 Dz-mediated cleavage. We observed that ODNs that hybridized close to 5' and 3' ends of the target sequence were able to enhance significantly 8-17 Dz-mediated cleavage activity in a dose-dependent manner. The same was true for 10-23 Dz with ODNs that hybridized close to the target site. Thus, it was possible to enhance significantly the cleavage activity of poorly cleaving HIV-1 Gag-specific Dzs by using sequence-specific ODNs. This combination of antisense and catalytic Dz will, in principle, result in more effective gene suppression that could be exploited for therapeutic purposes.  相似文献   
24.
Inositol hexaphosphate (IP6) is a natural constituent found in almost all cereals and legumes. It is known to cause numerous antiangiogenic manifestations. Notwithstanding its great potential, it is underutilized due to the chelation and rapid excretion from the body. Jacalin is another natural constituent obtained from seeds of jackfruit and can target disaccharides overexpressed in tumor cells. The current study was in-quested to develop and evaluate a surface-modified gold nanoparticulate system containing IP6 and jacalin which may maximize the apoptotic effect of IP6 against HCT-15 cell lines. IP6 loaded jacalin-pectin-gold nanoparticles (IJP-GNPs) were developed through reduction followed by incubation method. The developed formulation was tested for various in vitro and in silico studies to investigate its potential. HCT-15 cells when exposed to IJP-GNP resulted in significant apoptotic effects in dose as well as time-dependent manner, as measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, micronucleus, and reactive oxygen species assay. IJP-GNP displayed cell cycle arrest at the G0/G1 phase. To further explore the mechanism of chemoprevention, in silico studies were performed. The docking results revealed that the interactive behavior of IP6, P-GNP, and jacalin could target and inhibit the tumor formation activity, supported by in vitro studies. Taken together, all the findings suggested that IP6 loaded nanoparticles may increase the hope of future drug delivery strategy for targeting colon cancer.  相似文献   
25.
Seasonal changes in the fatty acid composition of phospholipids (PL), monoglycerides (MG), diglycerides (DG), free fatty acids (FA) and triglycerides (TG) separated from oleosomes (lipid bodies) of perennial root nodules of beach pea (Lathyrus maritimus) were analysed. Thin layer chromatography (TLC) revealed that PL and MG are the major lipids in nodule oleosomes. The fatty acid profile and overall double bond index (DBI) varied among lipid classes depending upon the season. High DBI in PL and MG found during late winter and early spring indicated that they may play a major role in winter survival and regeneration of perennial nodules. The DBI of DG was high at the end of the fall season and the DBI of FA and TG was high in summer months. The dominant fatty acids are C16:0 followed by C18:0 and C18:1. The levels of many unsaturated fatty acids such as C18:1, C18:2 and C18:3 increased while saturated fatty acid C18:0 decreased during winter. These unsaturated fatty acids possibly play an important role in the protection of nodule cells from cold stress. Nodules seem to retain some fatty acids and selectively utilize specific fatty acids to survive the winter and regenerate in spring.  相似文献   
26.
A series of nineteen substituted 1,2,3,4,6,7,12,12a-octahydropyrazino[2',1':6,1]pyrido[3, 4-b]indoles analogues of neuroleptic drug, Centbutindole have been studied using quantitative structure-activity relationship analysis. The derived models display good fits to the experimental data (r>or=0.75) having good predictive power (r(cv)>or=0.688). The best model describes a high correlation between predicted and experimental activity data (r=0.967). Statistical analysis of the equation populations indicates that hydrophobicity (as measured by pi(R), logP(o/w) and SlogP_VSA8), dipole y and structural parameters in terms of indicator variable, (In(1)) and globularity are important variables in describing the variation in the neuroleptic activity in the series.  相似文献   
27.
28.
In the present study, an attempt was made to prepare immediate-release enteric-coated pellets of aceclofenac, a poorly soluble nonsteroidal anti-inflammatory drug that has a gastrointestinal intolerance as its serious side effect. Formulation of enteric-coated pellets with improved solubility of aceclofenac could address both of these problems. To achieve these goals, pellets were prepared by extrusion–spheronization method using pelletizing agents that can contribute to the faster disintegration and thereby improve the solubility of the drug. Different disintegrants like β-cyclodextrin, kollidon CL, Ac-Di-Sol, and sodium starch glycolate were tried in order to further improve disintegration time. The pellets were characterized for drug content, particle size distribution, flow properties, infrared spectroscopy, surface morphology, disintegration rate, and dissolution profile. The formulations, which showed best disintegration and dissolution profiles, were coated with Eudragit L100-55, an enteric-coated polymer which does not dissolve at gastric pH but dissolves at intestinal pH, releasing the drug immediately in the dissolution medium. The optimized enteric-coated formulation containing 20% κ-carrageenan, lactose, and sodium starch glycolate as a disintegrant did inhibit the release of the drug for 2 h in 0.1 N HCl, whereas 87% of the drug was released within 45 min. The improvement was substantial when it was compared with solubility of pure drug under the same conditions. Thus, dissolution profiles suggested that combination of κ-carrageenan and sodium starch glycolate resulted into fast-disintegrating, immediate-release pellets, overcoming the bioavailability problem of the poorly soluble drug, aceclofenac, and enteric coating of these pellets avoids the exposure of aceclofenac to ulcer-prone areas of the gastrointestinal tract.  相似文献   
29.
The continuous advancements in cancer research have contributed to the overwhelming evidence of the presence of telomerase in primary and secondary tumours together with hsp90 and c-Myc. This review will discuss the important role of telomerase together with hsp90 and c-Myc within the initiation and progression of gliomas. Also it will review the differential expression of these genes in the different grades of gliomas and the possibility of new treatments targeting these specific genes.  相似文献   
30.
A new series of functionalized amino acid derivatives N-substituted 1-N-(tert-butoxycarbonyl)-2,2-dimethyl-4-phenyl-5-oxazolidine carboxamide (1-17) and 1-N-substituted-3-amino-2-hydroxy-3-phenylpropane-1-carboxamide (18-34) were synthesized and evaluated for their in vitro cytotoxicity against human cancer cell lines. Compound 6 has shown interesting cytotoxicity (IC50 = 5.67 μm) in ovarian cancer, while compound 10 exhibited promising cytotoxicity in ovarian (IC50 = 6.1 μm) and oral (IC50 = 4.17 μm) cancers. These compounds could be of use in designing new anti-cancer agents.  相似文献   
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