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31.
Camel milk has high levels of antioxidant peptides; therefore has a significant role in nutrition and health. There is a wide range of diseases associated with oxidative stress in the body, thereby preventing the production of free radicals followed the occurrence of such reactions have an important role in human health. Some peptides derived from natural sources as natural antioxidants have a significant role in the inhibition of free radicals. The aim of this study was the identification and purification of camel milk proteins and evaluation of their antioxidant properties. For this purpose, camel milk proteins were hydrolyzed and examined the antioxidant properties of resulting peptides. Ultrafiltration and reverse-phase HPLC techniques were used for fractionation of the hydrolysate. Antioxidant activity of peptides were evaluated using different methods such as 2,2′-diphenyl-1-picrylhydrazyl (DPPH·), 2,2′-azinobis(3-ethylbenzothiazo-line-6-sulfonic acid) diammonium salt (ABTS+), superoxide (O2·?), hydroxyl (OH·?) and polyunsaturated fatty acid peroxidation assays. The real-time PCR was performed to evaluate changes in expression of superoxide dismutase gene (SOD) as an antioxidant enzyme in HepG2 cells treated with different concentrations of peptide. Active peaks were analyzed using tandem mass spectrometry and thus identified two peptides NEDNHPGALGEPV (NV-13) and KVLPVPQQMVPYPRQ (KQ-15) with 1348.38 and 1780.15 dalton molecular weight, respectively. Both peptides showed antioxidant effects but KQ-15 peptide showed stronger effects than other. Molecular analysis showed that KQ-15 peptide was also able to increase the expression of SOD gene. The results show that the NV-13 and KQ-15 peptides have a high antioxidant capacity and they can be used to deal with diseases associated with oxidative stress.  相似文献   
32.
Abstract

In this study, the interactions of a novel metal complex [Dy(bpy)2Cl3.OH2] (bpy is 2,2'-bipyridine) with fish salmon DNA (FS-DNA) and bovine serum albumin (BSA) were investigated by experimental and theoretical methods. All results suggested significant binding between the Dy(III) complex with FS-DNA and BSA. The binding constants (Kb), Stern-Volmer quenching constants (KSV) of Dy(III)-complex with FS-DNA and BSA at various temperatures as well as thermodynamic parameters using Van’t Hoff equation were obtained. The experimental results from absorption, ionic strength, iodide ion quenching, ethidium bromide (EtBr) quenching studies and positive ΔH? and ΔS? suggested that hydrophobic groove-binding mode played a predominant role in the binding of Dy(III)-complex with FS-DNA. Indeed, the molecular docking results for DNA-binding were in agreement with experimental data. Besides, the results found from experimental and molecular modeling indicated that the Dy(III)-complex bound to BSA via Van der Waals interactions. Moreover, the results of competitive tests by phenylbutazone, ibuprofen, and hemin (as a site-I, site-II and site-III markers, respectively) considered that the site-III of BSA is the most possible binding site for Dy(III)-complex. In addition, Dy(III) complex was concurrently screened for its antimicrobial activities. The presented data provide a promising platform for the development of novel metal complexes that target nucleic acids and proteins with antimicrobial activity.

Communicated by Ramaswamy H. Sarma  相似文献   
33.
The room temperature reactions of RSH (R = Et, Ph) with (CO)3Mo(μ-dppm)2Ru(CO)3 (1) in toluene yield (CO)2Mo(μ-SR)(μ-CO)(μ-dppm)2Ru(H)(CO) [R = Et (3); Ph (4)], which are characterized by elemental analysis, 1H NMR and IR spectroscopies and, in the case of 3, by X-ray crystallography. The complexes contain a trans,trans-Mo(μ-dppm)2Ru unit with a bridging thiolate, a terminal hydride at the Ru, three terminal CO ligands (two at the Mo, and one at the Ru), and one semi-bridged CO closer to the Mo.  相似文献   
34.
The sawfly, Arge rosae Linnaeus (Hymenoptera: Argidae) is a serious pest of rose plants in a vast area of the world including Iran. Pesticides are applied in order to control in areas where infestation is high. So, there is a need for more environmentally benign alternatives to control this insect pest in urban areas. Therefore, the aim of the current study was to study the effect of cereal seed proteinaceous extracts including wheat and triticale on the insect α-amylase. Wheat and triticale seed proteins as well as fourth instars larvae α-amylase were extracted. The results showed that there are two different α-amylase isoenzymes in the insect gut, one major band and the other minor band, which had optimal activity at alkaline pH (pH 8.0). The effect of five concentrations including 0.42, 0.21, 0.105, 0.05 and 0.025?mg?ml?1 of each seed extract was tested on α-amylase activity of the larvae gut. At the highest concentration (0.42?mg?ml?1), wheat seed extract caused 74% inhibition of the enzyme activity while triticale seed extract inhibited 62% enzyme activity. Experiments proved that seed proteinaceous extract affected the enzyme activity in a pH-dependant manner.  相似文献   
35.
Abstract

Macrophomina phaseolina causes charcoal root rot (CRR) in numerous crops worldwide. However, structural progression of CRR epidemics in association with bean agro-ecosystems is little understood. Thus, progression of CRR epidemics in interaction with 13 agro-ecological variables was characterised in 48 commercial bean fields. Frequency of pathogen isolated from root was assessed at vegetative (V3), flowering-podding (R6-7) and pod maturity (R9) growth stages. Two principal factors accounting for 89% of total data variance characterised CRR epidemics. Rhizobial nodulation and cultivation–depth, clay–pH, date–preceding crop, urea–bean class and urea–herbicide interactions accounted for 50% CRR epidemic dynamics. Sixty-five percent of production variance was explained by soil clay, bean class, colonisation, planting date and depth, cultivation method, preceding crop, nodulation, herbicide and urea application. The present findings enabled us to explain a noticeable part of variations in productivity among the bean CRR pathosystems with the help of certain agricultural and environmental events for sustainable agriculture purposes.  相似文献   
36.

Background:

The aim of this study was to evaluate the possible protective effect of sodium selenite on serum, liver, and kidney antioxidant enzymes activities in alloxan-induced type 1 diabetic rats.

Methods:

Forty Sprague-Dawley male rats were randomly divided into four groups; Group one as control, Group two as sham-treated with sodium selenite by 1 mg/kg intraperitoneal (i.p.) injections daily, Group three as diabetic untreated, and Group four as diabetic treated with sodium selenite by 1 mg/kg i.p. injections daily .Diabetes was induced in the third and fourth groups by subcutaneous alloxan injections. After eight weeks the animals were euthanized and livers and kidneys were immediately removed and used fresh or kept frozen until analysis. Before the rats were killed blood samples were also collected to measure glutathione peroxidase (GPX) and catalase (CAT) activities in sera.

Results:

Glutathione peroxidase and CAT activities serum, liver, and kidney were all significantly less in the diabetic rats than in the controls. Sodium selenite treatment of the diabetic rats resulted in significant increases in GPX activity in the kidneys and livers, and CAT activity in the sera and livers.

Conclusions:

Our results indicate that sodium selenite might be a potent antioxidant that exerts beneficial effects on both GPX and CAT activities in alloxan-induced type 1 diabetic rats. Key Words: Diabetes, Rat, Sodium selenite, Antioxidant enzymes activity  相似文献   
37.
Brain-derived neurotrophic factor (BDNF) plays a role in mediating molecular, cellular, and behavioral adaptations underlying drug addiction. Here, we examined the influence of withdrawal from repeated morphine treatment on the expression of BDNF mRNA in the ventral tegmental area (VTA) and locus coeruleus (LC) of the rat brain. We also studied whether alternations in mRNA levels of BDNF in these tissues are associated with histone modifications around promoters II and III of the BDNF gene. Thus, chromatin immunoprecipitation (CHIP) and quantitative (q)-PCR were employed to assess acetylation of histone H3 at K9/K14 and trimethylation of histone H3 at K9. Results of qRT-PCR showed that levels of BDNF mRNA in both VTA and LC were significantly increased 7 days rather than 2 h or 24 h following the last injection of morphine. Consistently, CHIP and qPCR analysis revealed that on day 7 of morphine abstinence, both VTA and LC levels of histone methylation at BDNF promoters II and III of morphine treated rats were significantly lower than control animals. Morphine withdrawal caused only a significant increase in H3 acetylation at the promoter II in the LC. These data demonstrate the involvement of histone H3 methylation in the regulation of gene expression in the VTA and LC of rats during forced abstinence of morphine.  相似文献   
38.
39.
Colorectal cancer (CRC) is known as one of the most important causes of death and mortality worldwide. Although several efforts have been made for finding new therapies, no achievements have been made in this area. Multidrug resistance (MDR) mechanisms are one of the key factors that could lead to the failure of chemotherapy. Moreover, it has been shown that various chemotherapy drugs are associated with several side effects. Hence, it seems that finding new drugs or new therapeutic platforms is required. Among different therapeutic approaches, utilization of nanoparticles (NPs) for targeting a variety of molecules such as siRNAs are associated with good results for the treatment of CRC. Targeting siRNA-mediated NPs could turn off the effects of oncogenes and MDR-related genes. In the current study, we summarized various siRNAs targeted by NPs which could be used for the treatment of CRC. Moreover, we highlighted other routes such as liposome for targeting siRNAs in CRC therapy.  相似文献   
40.
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