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41.
Research on the frequency of the highly functional mutations of genes coding required for metabolizing enzymes has shown significant ethnic variations. However, few studies, if any, have examined the frequency distribution of major allelic variations in the context of Iran. In this regard, the present study focused on the genotype profile of Southern Iranians in order to compare allele frequencies of their CYP3A5 and P2Y12 (T744C) which have been shown to have roles in metabolizing clopidogrel, with those of other populations. Therefore, genotyping was carried out on 112 unrelated individuals by PCR–RFLP. The CYP3A5*3 allele was found in 185 persons with allelic frequency 0.82, which is the most common allele among Caucasians (90–95%). The frequency of 82% is different from other Caucasians (90–94%), Indians (67%), Vietnam (67%) and Africans (15%). but lower than frequency in Chinese populations (74%) and Korean (76%). The allele frequency of the −744T (4%) is different from frequencies of Caucasian, American, Chinese, Korean, and Subsahara population. This study confirmed significant inter-ethnic differences in CYP3A5 and P2Y12 frequencies between Iranians and other ethnic groups. The results of this study will be useful for clinical pharmacokinetic investigations and drug dosage recommendations especially antiplatelet drugs such as Clopidogrel, for Iranians.  相似文献   
42.
Aquatic escape responses have typically been described as C-starts. However, another aquatic escape response, head retraction, occurs in several elongate species, but has never been studied in detail. The goals of this study are to describe the head retraction escape response in a phylogenetically diverse sample of species, to trace the evolution of head retraction in anamniote vertebrates, and to correlate key morphological traits with escape response behavior. In analyzing the evolution of escape behavior, we found that the head retraction escape response has evolved at least six times in anamniote vertebrates. Using independent contrast analysis, the head retraction escape response was found to be correlated with an increase in the total number of vertebrae and an increase in the elongation of an animal. Results from this study indicate a correlation between head retraction as an escape response, elongation of the axial skeleton, and living in structured habitats.  相似文献   
43.
Schwann cells (SCs), the supporting cells of the peripheral nerves, are indispensable for regenerating the peripheral and central nervous system. Copious preparation of these cells in a well-defined manner is to be a privileged position. SCs cultivation is overwhelmed by contaminating fibroblasts which are often outgrowing as the predominant cell type in an in vitro culture. This study introduces a technically simple and efficient procedure for SCs isolation and enrichment based on implementing recombinant and defined supplements. Collected adult rat sciatic nerves were cultured for 10 days as in vitro predegeneration. After dissociation and plating, the medium changed to knockout serum replacement supplemented DMDM/F12 medium containing various growth factors. The whole procedure took 3 weeks and SCs purity was then evaluated through implementing specific cytoplasmic and membranous markers. The viability of enriched SCs were evaluated by MTT assay. Within 10 days, over 99 % homogenous SCs were achieved and confirmed through immunofluorescence staining and flow-cytometry for P75NTR and S100 markers, respectively. MTT data revealed that the viability and metabolic activities of purified SCs were increased in expansion medium. This study provides a technically easy and efficient method with the benefits of not utilizing bovine serum or other animal products for SCs isolation and enrichment.  相似文献   
44.
Ghasemi  Samira  Harighi  Behrouz  Mojarrab  Mahdi  Azizi  Abdolbaset 《BioControl》2021,66(3):421-432

Volatile organic compounds (VOCs) produced by bacteria have significant potential to control phytopathogens. In this study, the VOCs produced by endofungal bacteria Pseudomonas sp. Bi1, Bacillus sp. De3, Pantoea sp. Ma3 and Pseudomonas sp. De1 isolated from wild growing mushrooms were evaluated in vitro for their antagonistic activity against Pseudomonas tolaasii Pt18, the causal agent of mushroom brown blotch disease. The gas chromatography–mass spectrometry (GC–MS) analysis revealed that strains Pseudomonas sp. Bi1, Pseudomonas sp. De1, Bacillus sp. De3 and Pantoea sp. Ma3 produced eight, sixteen, nine, and twelve VOCs, respectively. All antagonistic endofungal bacteria produced VOCs which significantly reduced brown blotch symptoms on mushroom caps and inhibited the growth of P. tolaasii Pt18 at the varying levels. Scanning electron microscopy revealed severe morphological changes in cells of P. tolaasii Pt18 following exposure to the VOCs of Pseudomonas sp. Bi1 and De1. Furthermore, The VOCs produced by endofungal bacteria significantly reduced swarming, swimming, twitching, chemotaxis motility and biofilm formation by P. tolaasii Pt18 cells, which are essential contributors to pathogenicity. This is to first report about the inhibition effects of VOCs produced by antagonistic bacteria on virulence traits of P. tolaasii. Our findings provide new insights regarding the potential of antibacterial VOCs as a safe fumigant to control mushroom brown blotch disease.

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45.
This paper addresses the geometrical, charge, topological, and thermochemical data for the adsorption of the relevant furan species during hydrogenation of furfural to furfuryl alcohol over Cu/SiO2 and Cu/MgO catalysts. The calculations indicated that the binding of Cu to magnesia was stronger than that on silica. The results also indicated that the formation of an alkoxide intermediate is more favoured than that of a hydroxyalkyl species. The binding energetic data were in general agreement with the geometrical parameters, electron densities, and molecular orbital energy levels. The QTAIM data revealed the closed-shell interactions between Cu and O atoms on both of the catalysts. Finally, the analysis of the partial charges on the atoms revealed that the Cu atom acquires a positive charge upon interaction with the carbonyl group owing to a π-back-donation from Cu to the C?=?O bond.  相似文献   
46.
47.
Cheese whey fermentation to ethanol using immobilized Kluyveromyces marxianus cells was investigated in batch and continuous operation. In batch fermentation, the yeast cells were immobilized in carboxymethyl cellulose (CMC) polymer and also synthesized graft copolymer of CMC with N-vinyl-2-pyrrolidone, denoted as CMC-g-PVP, and the efficiency of the two developed cell entrapped beads for lactose fermentation to ethanol was examined. The yeast cells immobilized in CMC-g-PVP performed slightly better than CMC with ethanol production yields of 0.52 and 0.49 g ethanol/g lactose, respectively. The effect of supplementation of cheese whey with lactose (42, 70, 100 and 150 g/l) on fermentative performance of K. marxianus immobilized in CMC beads was considered and the results were used for kinetic studies. The first order reaction model was suitable to describe the kinetics of substrate utilization and modified Gompertz model was quite successful to predict the ethanol production. For continuous ethanol fermentation, a packed-bed immobilized cell reactor (ICR) was operated at several hydraulic retention times; HRTs of 11, 15 and 30 h. At the HRT of 30 h, the ethanol production yield using CMC beads was 0.49 g/g which implies that 91.07 % of the theoretical yield was achieved.  相似文献   
48.
"Candidatus Phytoplasma aurantifolia" is the causative agent of witches' broom disease in the Mexican lime tree (Citrus aurantifolia L.), and is responsible for major tree losses in Southern Iran and Oman. The pathogen is strictly biotrophic, and, therefore, completely dependent on living host cells for its survival. The molecular basis of compatibility and disease development in this system is poorly understood. We applied a proteomics approach to analyse gene expression in Mexican limes infected with "Ca. Phytoplasma aurantifolia". Leaf samples were collected from healthy and infected plants and were analysed using 2-DE coupled with MS. Among 800 leaf proteins that were detected reproducibly in eight biological replicates of healthy and eight biological replicates of infected plants, 55 showed a significant response to the disease. MS resulted in identification of 39 regulated proteins, which included proteins that were involved in oxidative stress defence, photosynthesis, metabolism, and the stress response. Our results provide the first proteomic view of the molecular basis of the infection process and identify genes that could help inhibit the effects of the pathogen.  相似文献   
49.
Naturally-derived drugs have drawn much attention in recent decades. Efficiency, lower toxicity, and economic reasons are some of their advantages that justify this broad range of administration for different diseases, including cancer. If we can find a specific combination that boosts the effects of their single therapy, leading to synergism effect, increased efficiency, and decreased toxicity, they can act even better. Quercetin and fisetin, two well-known flavonoids, have been used to fight against various cancers. In this study, we investigated their possible synergism quercetin and fisetin on MCF7, MDA-MB-231, BT549, T47D, and 4T1 breast cancer cell lines. Then the optimum combined dose was used to study their impacts on wound healing abilities and clonogenic properties. The real-time qPCR was used to study the expression of their validated downstream effectors in predicted pathways. A significant synergism effect (p < .01, combination index: <1) was observed for all cell lines. Combination therapy was significantly more effective in colony formation (p < .0001) and wound healing assays (p < .001) compared to single therapies. The expression level of potential effectors was also showed a greater change. In vivo study confirmed the in vitro results and showed how significantly (p < .001) their synergism promotes their singular function in inhibiting cancer progression. The breast cancer mouse models receiving combined therapy lived longer with higher average body weight and smaller tumor sizes. These results exhibit that quercetin and fisetin inhibit cancer cell proliferation, migration and colony formation synergistically, and matrix metalloproteinase signaling and apoptotic pathways are relatively responsible for inhibitory activities.  相似文献   
50.
3-Hydroxybutyrate, one of the main blood ketone bodies, has been considered as a critical indicator for diagnosis of diabetic ketoacidosis. Biosensors designed for detection of 3-hydroxybutyrate with advantages of precision, easiness and speedy performance have attracted increasing attention. This study attempted to develop a 3-hydroxybutyrate dehydrogenase-based biosensor in which single-walled carbon nanotubes (SWCNT) was used in order to immobilize the cofactor, NAD+, on the surface of screen-printed electrode. The formation of NAD+–SWCNT conjugates was assessed by electrochemistry and electron microscopy. Cyclic voltammetry was used to analyze the performance of this biosensor electrochemically. The considerable shelf life and reliability of the proposed biosensor to analyze real sample was confirmed by this method. The reduction in the over potential of electrochemical oxidation of NADH to ?0.15 V can be mentioned as a prominent feature of this biosensor. This biosensor can detect 3-hydroxybutyrate in the linear range of 0.01–0.1 mM with the low detection limit of 0.009 mM. Simultaneous application of screen-printed electrode and SWCNT has made the biosensor distinguished which can open new prospects for detection of other clinically significant metabolites.  相似文献   
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