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Plant Cell, Tissue and Organ Culture (PCTOC) - Melittin peptide is the main component of honey bee venom with the cytotoxic and anti-cancer effect which can affect healthy and cancerous cells...  相似文献   
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Catalytic combustion of hydrocarbons is an important technology to produce energy. Compared to conventional flame combustion, the catalyst enables this process to operate at lower temperatures; hence, reducing the energy required for efficient combustion. The reaction and activation energies of direct combustion of hydrocarbons (CH?→?C?+?H) on a series of metal surfaces were investigated using density functional theory (DFT). The data obtained for the Ag, Au, Al, Cu, Rh, Pt, and Pd surfaces were used to investigate the validity of the Brønsted-Evans-Polanyi (BEP) and transition state scaling (TSS) relations for this reaction on these surfaces. These relations were found to be valid (R2?=?0.94 for the BEP correlation and R2?=?1.0 for the TSS correlation) and were therefore used to estimate the energetics of the combustion reaction on Ni, Co, and Fe surfaces. It was found that the estimated transition state and activation energies (ETS?=??69.70 eV and Ea?=?1.20 eV for Ni, ETS?=??87.93 eV and Ea?=?1.08 eV for Co and ETS?=??92.45 eV and Ea?=?0.83 eV for Fe) are in agreement with those obtained by DFT calculations (ETS?=??69.98 eV and Ea?=?1.23 eV for Ni, ETS?=??87.88 eV and Ea?=?1.08 eV for Co and ETS?=??92.57 eV and Ea?=?0.79 eV for Fe). Therefore, these relations can be used to predict energetics of this reaction on these surfaces without doing the time consuming transition state calculations. Also, the calculations show that the activation barrier for CH dissociation decreases in the order Ag ? Au ? Al ? Cu ? Pt ? Pd ? Ni?>?Co?>?Rh?>?Fe.  相似文献   
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Laccase catalyzes the oxidation of various phenolic compounds that can be used in a wide range of industrial applications such as waste detoxification and the textile industry. In the present study, we generated transplastomic tobacco plants to develop a reliable commercial source of laccase production. The stability of the laccase protein in the transgenic plants was increased by using the enhancer sequence from green fluorescent protein, resulting in three independent lines with high levels of laccase accumulation (up to 2?% of total protein); significant laccase activity, however, was not detected. Interestingly, the transplastomic lines showed slightly retarded vegetative growth, with a light green leaf color in comparison with the control, which may be attributable to copper deficiency induced by ligand chelation by abundantly produced laccase. These results suggest that the tobacco chloroplast is an efficient system for the mass production of laccase protein, but further studies are needed to obtain active enzyme.  相似文献   
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Plastids from Nicotiana benthamiana were transformed with the vector for dicistronic expression of two genes—aminoglycoside 3'-adenyltransferase (aadA) and green fluorescent protein (gfp)—in the plastids of Nicotiana tabacum. Transplastomic shoots exhibited green fluorescence under UV light. Transformation efficiencies were similar between species. Although the border sequence (trnI and trnA) for homologous recombination to transform the plastid genome of N. benthamiana was identical to that sequence of N. tabacum, the exception was a 9-bp addition in the intron of trnI. This indicated that the N. tabacum sequence used as a border region for recombination was sufficient to insert the foreign gene into the target site between the trnI and trnA of N. benthamiana with similar efficiency. Southern blot analysis detected the presence of aadA and gfp between trnI and trnA in the plastid genome of N. benthamiana. Northern and western blot analyses revealed high expression of gfp in the plastids from petals and leaves. Our results suggest that the plastid transformation system established here is applicable to investigations of the interactions between plastid and nucleus in N. benthamiana.  相似文献   
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This study reports the in vitro anticoagulation activity of acetonic extract (AE) of 42 lichen species and the identification of potential bioavailable anticoagulant compounds from Umbilicaria decussata as a competent anticoagulant lichen species. Lichens’ AEs were evaluated for their anticoagulant activity by monitoring activated partial thromboplastin time (APTT) and prothrombin time (PT) assays. A strong, positive correlation was observed between total phenolics concentration (TPC) of species and blood coagulation parameters. U. decussata was the only species with the longest clotting time in both APTT and PT assays. The research was moved forward by performing in vivo assays using rats. The results corroborated the dose-dependent impact of U. decussata’s AE on rats’ clotting time. Major secondary metabolites of U. decussata and their plasma-related bioavailability were also investigated using LC-ESI-MS/MS. Atranol, orsellinic acid, D-mannitol, lecanoric acid, and evernic acid were detected as possible bioavailable anticoagulants of U. decussata. Our findings suggest that U. decussata might be a potential anticoagulant lichen species that can be used for the prevention or treatment of coagulation-related issues such as cardiovascular diseases (CVDs).  相似文献   
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International Journal of Peptide Research and Therapeutics - Hepatitis C virus (HCV) is an important causative agent of acute and chronic hepatitis. The non-structural protein 3 (NS3) of HCV...  相似文献   
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Background: Helicobacter pylori infection of the stomach is widespread among human populations and is considered to play a major role in the pathogenesis of various diseases such as peptic ulcer, adenocarcinoma, and mucosa associated lymphoid tissue (MALT) lymphoma of the stomach. To increase H. pylori eradication rate without increasing bacterial resistance, various regimens have been recommended. Commonly the association of at least two antibiotics with a proton‐pump inhibitor is used. The treatment regimens for second‐line therapy, suggested in studies from the western world may not be ideal in Iran. Aim: In this study, we evaluated the safety and efficacy of a new quadruple therapy regimen and compared it with the standard second‐line treatment for H. pylori eradication. Methods: We selected 220 H. pylori positive patients, with a clear indication of eradication therapy, who did not respond to a 2 weeks treatment with metronidazole, amoxicillin, omeprazole, and bismuth. They were randomized into two groups. Group A (n = 110) were treated with azithromycin, ofloxacin, bismuth, and omeprazole and group B (n = 110) with amoxicillin, clarithromycin, bismuth, and omeprazole for 2 weeks. Four weeks after the end of treatment, urea breath test was performed for all subjects to confirm eradication. Results: In intention‐to‐treat analysis, the rate of H. pylori eradication in groups A and B was 77.3% (85/110) and 64.5% (71/110) respectively (p = .027). In per‐protocol analysis, the rate of H. pylori eradication in groups A and B was 86.7 and 74.7%, respectively (p = .026). The incidence of poor compliance was lower, although not significantly so, in group A than group B (3.5 vs 4.3%). No major adverse events occurred in both groups. Conclusion: Two weeks of treatment with ofloxacin, azithromycin, omeprazole, and bismuth is an effective and safe regimen for H. pylori eradication as second‐line therapy.  相似文献   
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