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251.
International Journal of Peptide Research and Therapeutics - Irisin is a soluble and exercise-induced myokine and/or adipokine hormone; generated by FNDC5 (a gene precursor) and also, it can...  相似文献   
252.
The incidence of esophageal squamous cell carcinoma (ESCC) is very high in northeastern Iran. Previously, we reported a strong familial component of ESCC among Turkmens, who constitute approximately one-half of the population of this region. We hypothesized that the genes which cause Fanconi anemia might be candidate genes for ESCC. We sequenced the entire coding regions of 12 Fanconi anemia genes in the germline DNA of 190 Turkmen cases of ESCC. We identified three heterozygous insertion/deletion mutations: one in FANCD2 (p.Val1233del), one in FANCE (p.Val311SerfsX2), and one in FANCL (p.Thr367AsnfsX13). All three patients had a strong family history of ESCC. In addition, four patients (out of 746 tested) were homozygous for the FANCA p.Ser858Arg mutation, compared to none of 1,373 matched controls (OR?=?16.7, 95% CI?=?6.2-44.2, P?=?0.01). The p. Lys3326X mutation in BRCA2 (also known as Fanconi anemia gene FANCD1) was present in 27 of 746 ESCC cases and in 16 of 1,373 controls (OR?=?3.38, 95% CI?=?1.97-6.91, P?=?0.0002). In summary, both heterozygous and homozygous mutations in several Fanconi anemia-predisposing genes are associated with an increased risk of ESCC in Iran.  相似文献   
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The inhalation of Chenopodium album (C. album) pollen has been reported as an important cause of allergic respiratory symptoms. The aim of this study was to produce the recombinant profilin of C. album (rChe a 2) pollen and to investigate its cross-reactivity with other plant-derived profilins based on potential conformational epitopes and IgE reactivity analysis. Che a 2-coding sequence was cloned, expressed, and purified using one step metal affinity chromatography to recover high-purity target protein. We assessed cross-reactivity and predicted IgE potential epitopes among rChe a 2 and other plant-derived profilins. Immunodetection and inhibition assays using sixteen individual sera from C. album allergic patients demonstrated that purified rChe a 2 could be the same as that in the crude extract. The results of inhibition assays among rChe a 2 and other plant-derived profilins were in accordance with those of the homology of predicted conserved conformational regions. In this study, amino acid sequence homology analysis showed that a high degree of IgE cross-reactivity among plant-derived profilins may depend on predicted potential IgE epitopes.  相似文献   
255.
Khan AU  Islam B  Khan SN  Akram M 《Bioinformation》2011,5(10):440-445
Biofilm formation by Streptococcus mutans is considered as its principal virulence factor, causing dental caries. Mutants of S. mutans defective in biofilm formation were generated and analyzed to study the collective role of proteins in its formation. Mutants were characterized on the basis of adherence to saliva-coated surface, and biofilm formation. The confocal laser microscopy and scanning electron microscopy images showed that the control biofilms had cluster of cells covered by layer of exo-polysaccharide while the biofilms of mutants were thin and spaced. Two-dimensional protein electrophoresis data analysis identified 57 proteins that are either up (44 proteins) or down (13 proteins) regulated. These data points to the importance of up and down regulated proteins in the formation of biofilm in Streptococcus mutans.  相似文献   
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The effect of microwave modulated with square waves of different pulse repetition frequencies was studied on the physiologic behavior of the cyanobacterium Schizothrix mexicana Gomont (Oscillatorials). The organism was exposed for 2 h to microwave (9.685 GHz) modulated with square wave pulse repetition frequencies of 900, 720, 540, 360 and 180 Hz at a fixed incident power density (0.768 mW/cm2). Results revealed that growth rate, dry weight and photosynthetic pigments increased significantly especially in frequency of 540 Hz. Total carbohydrate and protein contents, and photosynthesis and nitrogenase activity showed drastic increase in 180, 360 and 540 Hz and dropped down when treated with 720 and 900 Hz frequency. This study revealed that the increase effect of microwave radiation on metabolism of Schizothrix mexicana was found to be frequency dependent. So, electrostimulation of Schizothrix mexicana provides a new extended domain of disciplines and methodologies for cultivation, processing of biomass and biofuels, biofertilizers and biotechnology applications. This study reveals that microwaves athermally induce different biologic effects.  相似文献   
258.
Abstract

Here, we report on the effect of aspirin (ASA), on the binding parameters with regard to bilirubin (BR) to human serum albumin (HSA). Two different classes of binding sites were detected. Binding to the first and second classes of the binding sites was dominated by hydrophobic forces in the case of HSA-BR, whereas in the case of the ternary system, binding to the first and second classes of the binding sites was achieved by electrostatic interaction. The binding constant (Ka) and number of binding site (n) obtained were 1.6 × 106 M?1 and 0.98, respectively, for the primary binding site in the case of HSA-BR, and 3.7 × 106 M?1 and 0.84, respectively, in the presence of ASA (ternary complex) at δex = 280 nm. The progressive quenching of the protein fluorescence as the BR concentration increased indicated an arrangement of the domain IIA in HSA. Changes in the environment of the aromatic residues were also observed by synchronous fluorescence spectroscopy (SFS). Changes of the secondary structure of HSA involving a decrease of α-helical and β-sheet contents and increased amounts of turns and unordered conformations were mainly found at high concentrations of BR. For the first time, the relationship between the structural parameters of HSA-BR by RLS for determining the critical induced aggregation concentration (CCIAC) of BR in the absence and presence of ASA was investigated, and there was a more significant enhancement in the case of the ternary mixture as opposed to the binary one. Changes in the zeta potential of HSA and the HSA-ASA complex in the presence of BR demonstrated a hydrophobic adsorption of this anionic ligand onto the surface of HSA in the binary system as well as both electrostatic and hydrophobic adsorption in the case of the ternary complex. By performing docking experiments, it was found that the acting forces between BR and HSA were mainly hydrophobic > hydrogen bonding > electrostatic interactions, and consequently BR had a long storage time in blood plasma, especially in the presence of ASA. This was due to the electrostatic interaction force between the BR and HSA being stronger in (HSA-ASA) BR than in the HSA-BR complex. In addition, it was demonstrated that, in the presence of ASA, the first binding site of BR on HSA was altered, but the parameters of binding did not become significantly modified, and thus the affinity of BR barely changed with and without ASA.  相似文献   
259.
The lipophilic vitamin E, α-Tocopherol (α-Toc), has been considered as a potent cellular antioxidant naturally occurring in biological membranes. It plays a number of key metabolic roles in plants exposed to various stressful cues. A field experimental was conducted on mungbean [Vigna radiata (L.) Wilczek] under varying water-limited regimes and the plants were sprayed with four levels of α-Toc (0, 100, 200, and 300 mg L?1) at the vegetative stage of plant growth. The results showed that limited field irrigation regimes (desiccated conditions) caused a marked reduction in growth parameters (shoot and root fresh and dry weights; shoot and root lengths), photosynthetic pigments (chlorophyll a and b), total soluble proteins (TSP) and yield attributes (number of pods, seeds per plant, weight of ripened pods and 100-seeds weight), while, in contrast, water deficiency induced an increase in phenolics, proline, glycine betaine (GB), hydrogen peroxide (H2O2), malondialdehyde (MDA), reducing and non-reducing sugars, total free amino acids, endogenous tocopherol levels, and activities of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). However, the foliar spray of α-Toc significantly improved shoot and root fresh and dry weights, shoot and root lengths, chlorophyll a and b contents, phenolics, proline, GB, reducing and non-reducing sugars, TSP, total free amino acids, endogenous tocopherol level, and activities of antioxidant enzymes (SOD, POD, and CAT), as well as yield parameters. On the other hand, it significantly decreased the MDA and H2O2 levels. Of all varying levels of α-Toc used, 100 mg L?1 was most effective in causing enhanced accumulation of ascorbic acid (AsA), MDA, and cellular tocopherols particularly in cv. Cyclone 7008, while proline and catalase in cv. Cyclone 8009. Of both cultivars, Cyclone 7008 was superior to the other cultivar in proline, TSP, SOD, and POD enzymes, but cv. Cyclone 8009 being superior in shoot fresh weights, root fresh weight, shoot and root lengths, chlorophyll a and b, phenolics, H2O2, AsA, MDA, CAT, number of pods, seeds, weight of ripened pods, and weight of 100 seeds under dry land conditions. Overall, exogenously applied tocopherol improved yield and myriad of key physio-biochemical attribute in mungbean.  相似文献   
260.
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