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941.
Sterol glycosyltransferases regulate the properties of sterols by catalyzing the transfer of carbohydrate molecules to the sterol moiety for the synthesis of steryl glycosides and acyl steryl glycosides. We have analyzed the functional role of TTG15/UGT80B1 gene of Arabidopsis thaliana in freeze/thaw and heat shock stress using T-DNA insertional sgt knockout mutants. Quantitative study of spatial as well as temporal gene expression showed tissue-specific and dynamic expression patterns throughout the growth stages. Comparative responses of Col-0, TTG15/UGT80B1 knockout mutant and p35S:TTG15/UGT80B1 restored lines were analyzed under heat and freeze stress conditions. Heat tolerance was determined by survival of plants at 42°C for 3 h, MDA analysis and chlorophyll fluorescence image (CFI) analysis. Freezing tolerance was determined by survival of the plants at -1°C temperature in non-acclimatized (NA) and cold acclimatized (CA) conditions and also by CFI analysis, which revealed that, p35S:TTG15/UGT80B1 restored plants were more adapted to freeze stress than TTG15/UGT80B1 knockout mutant under CA condition. HPLC analysis of the plants showed reduced sterol glycoside in mutant seedlings as compared to other genotypes. Following CA condition, both β-sitosterol and sitosterol glycoside quantity was more in Col-0 and p35S:TTG15/UGT80B1 restored lines, whereas it was significantly less in TTG15/UGT80B1 knockout mutants. From these results, it may be concluded that due to low content of free sterols and sterol glycosides, the physiology of mutant plants was more affected during both, the chilling and heat stress.  相似文献   
942.
943.
Cold plasma technology is an efficient, environmental-friendly, economic and noninvasive technology; and in recent years these advantages placed this novel technology at the centre of diverse studies for food industry applications. Dried food ingredients including spices, herbs, powders and seeds are an important part of the human diet; and the growing demands of consumers for higher quality and safe food products have led to increased research into alternative decontamination methods. Numerous studies have investigated the effect of nonthermal plasma on dried food ingredients for food safety and quality purposes. This review provides critical review on potential of cold plasma for disinfection of dried food surfaces (spices, herbs and seeds), improvement of functional and rheological properties of dried ingredients (powders, proteins and starches). The review further highlights the benefits of plasma treatment for enhancement of seeds performance and germination yield which could be applied in agricultural sector in near future. Different studies applying plasma technology for control of pathogens and spoilage micro-organisms and modification of food quality and germination of dried food products followed by benefits and current challenges are presented. However, more systemic research needs to be addressed for successful adoption of this technology in food industry.  相似文献   
944.
International Journal of Peptide Research and Therapeutics - The extensive use of antibiotics in medical, as well as in veterinary practices has led to the development of antibiotic resistance...  相似文献   
945.
International Journal of Peptide Research and Therapeutics - Antimicrobial peptides (AMPs) offer a novel alternative to present day antibiotics which are becoming ineffective due to development of...  相似文献   
946.
Genetic variants in a number of immunoregulatory genes have been previously associated with health and production traits in dairy cattle. Therefore, in the following study, the genes coding interferon gamma (IFNG), IFNG receptor 1 and 2 domains, interleukin-22 (IL22), and IL22 receptor alpha 1, were investigated for single nucleotide polymorphisms (SNPs) in Holstein bulls. These SNPs, along with SNPs previously identified in IL10, IL10 receptor, and transforming growth factor beta 1 (TGFB1) genes, were evaluated for statistical associations to estimated breeding values for milk somatic cell score (SCS), a trait highly correlated to mastitis incidence, and various production-related traits, including milk yield, protein yield, fat yield, and lactation persistency. While no significant associations were found between these SNPs and SCS, SNPs in IL10 receptor beta subunit showed a significant effect on protein yield and lactation persistency. While there is evidence that IL10 plays an important role during lactation, it is also likely that the effects of SNPs in IL10 receptor beta subunit on protein yield and lactation persistency are due to linkage disequilibrium with a neighboring QTL.  相似文献   
947.
This study describes the synthesis of a new class of substrate-selective molecularly imprinted polymer. This involved tetraethylene glycol 3-morpholin propionate acrylate (functional monomer) and bovine serum albumin (template) for polymerization in aqueous condition, using "surface grafting-from" approach directly on a vinyl exposed multiwalled carbon nanotubes-ceramic electrode. The analyte recapture at pH 6.8 in aqueous environment simultaneously involved hydrophobically driven hydrogen bonds and ionic interactions between negatively charged bovine serum albumin and positively charged imprinted nanofilm. The selectively encapsulated bovine serum albumin first gets reduced at -0.9V and then oxidized within the cavity, without getting stripped off, to respond a differential pulse voltammetry signal. The limit of detection [0.42ngmL(-1) (3σ, RSD≤1.02%)] obtained was free from any cross-reactivity and matrix complications in aqueous, pharmaceutical, serum, and liquid milk samples. The proposed sensor can be used as a practical sensor for ultra-trace analysis of bovine serum albumin in clinical settings.  相似文献   
948.
Simple and efficient synthesis of quebecol and a number of its analogs was accomplished in five steps. The synthesized compounds were evaluated for antiproliferative activities against human cervix adenocarcinoma (HeLa), human ovarian carcinoma (SK-OV-3), human colon carcinoma (HT-29), and human breast adenocarcinoma (MCF-7) cancer cell lines. Among all the compounds, 7c, 7d, 7f, and 8f exhibited antiproliferative activities against four tested cell lines with inhibition over 80% at 75 μM after 72 h, whereas, compound 7b and 7g were more selective towards MCF-7 cell line. The IC50 values for compounds 7c, 7d, and 7f were 85.1 μM, 78.7 μM, and 80.6 μM against MCF-7 cell line, respectively, showing slightly higher antiproliferative activtiy than the synthesized and isolated quebecol with an IC50 value of 104.2 μM against MCF-7.  相似文献   
949.
Sarcoplasmic reticulum (SR) Ca2 + release plays an essential role in mediating cardiac myocyte contraction. Depolarization of the plasma membrane results in influx of Ca2 + through l-type Ca2 + channels (LTCCs) that in turn triggers efflux of Ca2 + from the SR through ryanodine receptor type-2 channels (RyR2). This process known as Ca2 +-induced Ca2 +release (CICR) occurs within the dyadic region, where the adjacent transverse (T)-tubules and SR membranes allow RyR2 clusters to release SR Ca2 + following Ca2 + influx through adjacent LTCCs. SR Ca2 + released during systole binds to troponin-C and initiates actin–myosin cross-bridging, leading to muscle contraction. During diastole, the cytosolic Ca2 + concentration is restored by the resequestration of Ca2 + into the SR by SR/ER Ca2 +-ATPase (SERCA2a) and by the extrusion of Ca2 + via the Na+/Ca2 +-exchanger (NCX1). This whole process, entitled excitation–contraction (EC) coupling, is highly coordinated and determines the force of contraction, providing a link between the electrical and mechanical activities of cardiac muscle. In response to heart failure (HF), the heart undergoes maladaptive changes that result in depressed intracellular Ca2 + cycling and decreased SR Ca2 + concentrations. As a result, the amplitude of CICR is reduced resulting in less force production during EC coupling. In this review, we discuss the specific proteins that alter the regulation of Ca2 + during HF. In particular, we will focus on defects in RyR2-mediated SR Ca2 + release. This article is part of a Special Issue entitled: Heart failure pathogenesis and emerging diagnostic and therapeutic interventions.  相似文献   
950.
A series of aryl S,N-ketene acetals 7(af) was synthesized and evaluated for their in vitro and in vivo antileishmanial activity against Leishmania donovani. All the 6 compounds exhibited significant in vitro activity against intracellular amastigotes of L. donovani with IC50 values ranging from 1.2 to 3.5 μM and were found promising as compared with reference drugs, sodium stibogluconate (SSG) and paromomycin. On the basis of good selectivity indices (SI), they were further tested for their in vivo potential against L. donovani/hamster model. Two compounds 7a and 7b showed significant inhibition of parasite multiplication, 72% and 83%, respectively. These compounds were comparable with SSG and superior to paromomycin. Preliminary in vitro metabolic investigations were also performed to assess the metabolic stability and in vitro hepatic intrinsic clearance (Clint) of compound 7b in hamster liver microsomes.  相似文献   
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