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761.
Curcumin has multiple pharmacological effects, but it has poor stability. Complexation of curcumin with metals improves its stability. Here, the effects of vanadyl curcumin and vanadyl diacetylcurcumin on the function and structure of horseradish peroxidase enzyme were evaluated by spectroscopic techniques. Cytotoxic effect of the complexes was also assessed on MCF-7 breast cancer, bladder and LNCaP prostate carcinoma cell line. The results showed that the complexes improve catalytic activity of HRP, and also increase its tolerance against the oxidative condition. The result also indicated that the affinity of HRP for hydrogen peroxide substrate decreases, while the affinity increases for phenol substrate. Circular dichroism and fluorescence spectroscopies showed that compactness of the enzyme structure around the catalytic heme group and the distance between the heme group and tryptophan residue decreases after the binding. The antibacterial and cytotoxic results indicated that the complexes have anticancer potential, but they have no considerable antibacterial activity.  相似文献   
762.
763.
Cellular and Molecular Neurobiology - Cellular stress can lead to the production of reactive oxygen species (ROS) while autophagy, as a catabolic pathway, protects the cells against stress....  相似文献   
764.
Thymus vulgaris of family Lamiaceae is one of the most plants in pharmacy industries. In this study effect of Piriformospora indica and Sebacina vermifera on growth and development plant, yield and composition of the essential oil in a completely randomized design were evaluated in vitro and in pot culture experiments. Plants were studied by means of plant height, shoot fresh and dry weights, number of shoots, root length, root fresh and dry weights and essential oil analyses. The oil was extracted from the dry matter of shoots by hydro distillation, and their composition was determined by GC/MS. In vitro and in vivo cultures showed that plant height and root length increased in pots inoculated with S. vermifera and P. indica. Maximum fresh and dry weight (shoot and root), number of shoots were observed in pots inoculated with P. indica. In thyme inoculated with S. vermifera and P. indica oil yield increased as compared to non-inoculated control plants. GC and GC/MS revealed that the level of thymol was enhanced as the effect of S. vermifera and P. indica.  相似文献   
765.
Genetic diversity in a collection of 70 bread wheat ( Triticum aestivum ) genotypes was studied using 73 microsatellite [simple sequence repeat (SSR)] loci evenly spaced on wheat chromosomes. A total of 592 alleles with an average of 8.53 allele/locus were detected, of which 185 (31.25%) occurred only in a specific group of genotypes. A set of SSR markers consisted of 22 loci with polymorphic information content values of 0.80 or higher were selected for rapid fingerprinting of many genotypes. Average of gene diversity was 0.74 ± 0.017, and significant difference between observed and maximum theoretical values of gene diversity in the analysed SSR loci was obtained using a paired t -test. Genetic distance-based clustering methods including unweighted pair group method with arithmetic average and neighbour joining (NJ) were used for grouping of genotypes. The resulted dendrogram based on NJ and number of differences coefficient hinted of the existence of three groups. This grouping was in agreement with the pedigree information and confirmed by high within-group bootstrap value. A comparatively higher genetic diversity in the studied wheat collection as revealed by presence of high allelic diversity and large number of specific alleles could be utilised in development of new cultivars with desired characteristics.  相似文献   
766.
Background:Non-Hodgkin''s lymphomas comprise the most common hematological cancers worldwide and consist of a heterogenous group of malignancies affecting the lymphoid system. Treatment of non-Hodgkin’s lymphoma has been significantly enhanced with the addition of Rituximab to the standard chemotherapy regimen. However, even with the advancement of treatment patients continue to relapse and develop resistance to Rituximab, rendering subsequent treatments unsuccessful. The use of novel drugs with unique antitumor mechanisms has gained considerable attention. In this study, we explored the in vitro anti-cancer effects of the combined therapy of Rituximab and Nisin on human Burkitt’s lymphoma cells.Methods:The human Burkitt’s lymphoma cells lines, Raji and Daudi, were treated with Nisin, Rituximab, or a combination of the two agents at various concentrations. Cytotoxicity following treatment was determined using cell viability assay. The degree of apoptosis was verified via flow cytometric analysis using FITC annexin V/PI staining.Results:Our findings show that the combined treatment of Rituximab and Nisin results in a more significant reduction in the survival of Raji and Daudi Burkitt’s lymphoma cells, compared to Nisin or Rituximab treatment alone. Additionally, our results indicate that Nisin can induce a significant degree of apoptosis in the Burkitt’s lymphoma cells compared to the negative controls. However, the addition of Nisin to the Rituximab treatment synergistically enhances the apoptotic antitumor effect.Conclusion:This study demonstrates the synergistic antitumor effect of Nisin treatment in vitro to enhance tumor cell apoptosis and the potential value of Nisin as an adjunct therapy in the treatment of lymphoma.Key Words: Apoptosis, Burkitt’s lymphoma, Cell viability, Combination, Nisin, Rituximab  相似文献   
767.
Dimers of cytosine and its N1-methylated counterpart were investigated in gas-phase and in various solvents including chloroform, dimethylsulfoxide, and water. The studies were performed at DFT/M06-2X/6-31+G(d,p) level of theory. Relative stabilities of tautomers of cytosine solvated explicitly by a small number of solvent molecules were evaluated. Further solvation effect calculations for homodimers were carried out with conductor-like polarizable continuum model (CPCM). H-NMR shifts and IR frequencies for optimized structures were calculated and compared with available experimental data.  相似文献   
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