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关键词： Benzopyrene   Acrylamide   Degradation   Roasted coffee   Corona discharge plasma   E-tongue   E-nose  

摘要： This study was aimed to reduce the concentrations of benzopyrene (BaP) and acrylamide (ACR) in roasted coffee beans by corona discharge plasma jet (CDPJ). The initial concentrations of BaP and ACR in roasted beans were decreased by 53.6% and 32.0%, respectively, following CDPJ (powered by 20 kV DC/1.5 A) treatment for 60 min. The levels of total solid, total acid, chlorogenic acid, caffeine, trigonelline, and pH were insignificantly changed upon CDPJ treatment compared to controls. However, the concentration of total phenolic content and Agtron color values were altered significantly. The treatment of beans did not alter descriptive sensory properties of the corresponding coffee brews, except aroma and aftertaste characteristics. As the treatment time increased from 15 to 60 min, scores for aroma profiles in PCA plot were shifted from right to left, although overlapping was observed between 15- and 30-min-treated samples. Additionally, none of the treated samples were discriminated from the control by electronic tongue.

关键词： 3D printing   directional freezing   biochemical guidance   topographical guidance   nerve regeneration  

摘要： Biochemical and physical guidance cues are both pivotal for axonal guidance and nerve regeneration. However, fabrication of a platform that can integrate biochemical gradients and topographical guidance cues remains challenging, especially in a three-dimensional (3D) scaffold that closely mimics in vivo axonal outgrowth conditions and ready to be used for in vivo nerve repair. In this study, a new method was introduced to construct 3D scaffolds displaying continuous biochemical gradients along longitudinally oriented microchannels by combining the modified 3D printing and directional freezing techniques. Fluorescence analysis and ELISA results demonstrated that a continuous biochemical gradient was formed, and scanning electron microscopy revealed a longitudinally oriented microstructure. Dorsal root ganglia explants seeded on the longitudinal sections of the newly developed scaffold (scaffold with nerve growth factor gradient along oriented microstructure, G-NGF + OS) showed that 81.3 +/- 4.5% of neurites oriented within +/- 10 degrees, 0.3 +/- 0.1 of guidance ratio, and 1.5-fold of the average length of neurites on the high-nerve growth factor (NGF) concentration side compared to that on the low-NGF concentration side, which were significantly higher than those in the other groups. In addition, the G-NGF + OS scaffold was used to repair a 15 mm sciatic nerve defect in rats. Immunofluorescence staining, Fluoro-Gold retrograde tracing, and transmission electron microscopy results confirmed that the G-NGF + OS scaffold enhanced nerve regeneration to the distal target and promoted myelination of regenerated axons. More importantly, the sciatic functional index and the von Frey test demonstrated that the G-NGF + OS scaffold accelerated sensory and motor functional recovery. These results provide new insights into the importance of combining topographical guidance cues with bioactive molecule gradient cues for neural tissue engineering. The 3D scaffold displaying bioche

关键词： Tobacco   Nicotiana tabacum   Drought-hardening   Drought tolerance   Varieties   Antioxidant enzymes   Gene expression   SnRK2   AREB   DREB  

摘要： BackgroundDrought stress is the most harmful one among other abiotic stresses with negative impacts on crop growth and development. Drought-hardening is a feasible and widely used method in tobacco seedlings cultivation. It has gained extensive interests due to its role in improving drought tolerance. This research aimed to investigate the role of drought-hardening and to unravel the multiple mechanisms underlying tobacco drought tolerance and *** study was designed in which various drought-hardening treatments (CK (no drought-hardening), T1 (drought-hardening for 24h), T2 (drought-hardening for 48h), and T3 (drought-hardening for 72h)) were applied to two tobacco varieties namely HongHuaDaJinYuan (H) and Yun Yan-100 (Y). The findings presented a complete framework of drought-hardening effect at physiological, biochemical, and gene expression levels of the two tobacco varieties under drought stress. The results showed that T2 and T3 significantly reduced the growth of the two varieties under drought stress. Similarly, among the various drought-hardening treatments, T3 improved both the enzymatic (POD, CAT, APX) and non-enzymatic (AsA) defense systems along with the elevated levels of proline and soluble sugar to mitigate the negative effects of oxidative damage and bringing osmoregulation in tobacco plants. Finally, the various drought-hardening treatments (T1, T2, and T3) showed differential regulation of genes expressed in the two varieties, while, particularly T3 drought-hardening treatment-induced drought tolerance via the expression of various stress-responsive genes by triggering the biosynthesis pathways of proline (P5CS1), polyamines (ADC2), ABA-dependent (SnRK2, AREB1), and independent pathways (DREB2B), and antioxidant defense-related genes (CAT, APX1, GR2) in response to drought ***-hardening made significant contributions to drought tolerance and adaptation in two tobacco variety seedlings by reducing its growth a

关键词： Magnesium   Osteoblast   Cellmigration   SNAI2   ZO-1   ALPactivity  

摘要： Magnesium is well known as a biodegradable biomaterial that has been reported to promote bone remodeling in several studies;however, the underlying biological mechanism remains unclear. In the present study, the role of magnesium ions in the migration of U-2 OS cells, which are osteoblast-like cell lines, was investigated. Magnesium treatment did not significantly alter the global transcriptome of U-2 OS cells, but increased the protein expression level of SNAI2, an epithelial-mesenchymal transition (EMT) marker. In addition, it was confirmed that the junctional site localization of Zona-occludens 1 (ZO1), a representative tight junction protein, was destroyed by magnesium treatment;furthermore, it was determined that cytoplasmic localization increased, and alkaline phosphatase (ALP) activity increased. The obtained results on the mechanism by which magnesium is involved in osteoblast migration, which is important for fracture healing, will contribute to the understanding of the bone-formation process in patients with osteoporosis and musculoskeletal injury. (C) 2020 Elsevier Inc. All rights reserved.

关键词： FTIR spectroscopy and microspectroscopy imaging   liver diseases   biofluid analysis   multivariate data analysis   high-throughput analysis  

摘要： Chronic liver diseases progressively lead to cirrhosis, liver failure, and other complications. Fourier Transform Infrared (FTIR) spectroscopy and microspectroscopy imaging are rapidly advancing techniques with multiple benefits for early diagnosis, grading, and monitoring of a broad spectrum of liver diseases. FTIR provides a biochemical overview of a sample, which can be used to determine the need for further in-depth investigations. Numerous studies have showed that infrared imaging offers a great promise for understanding of disease pathogenesis compared to that of common histopathological investigations. Moreover, high-throughput infrared characterization of biofluids has attracted increased interests for a wide array of pathologic diagnosis. The use of infrared spectroscopy and microspectroscopy for diagnosis, grading, and monitoring of liver diseases requires an understanding of infrared microspectroscopy, sample preparation, data collection, analysis, and interpretation. This review provides a comprehensive and up-to-date review of FTIR spectroscopy and microspectroscopy characterization of biofluids and tissues related to hepatic diseases. Each section of this review highlights practical problems and solutions for conducting FTIR spectroscopy and microspectroscopy studies.

关键词： essential elements   geranium   growth traits   sugarcane bagasse compost  

摘要： Compost produced from sugarcane bagasse was substituted at a range of different concentrations into soil bedding medium mixture, to evaluate their effects on the growth ofPelargonium x hortorum. Plants were grown in a substrate mixture (25% leaf compost;25% cow manure;50% garden soil (volume) as control and substitution with different rates of sugarcane bagasse compost of 20%, 30%, 40%, 80% and 100% were applied in three replications. The results showed that application of sugarcane compost started to stimulate plant growth at 20% level and continued over other levels;however, there was no significant difference among sugarcane compost levels regarding many growth traits. Application of low rates particularly 20% resulted in the highest record regarding many morphological traits including number of leaves, lateral stems, flowering shoots, flowers, inflorescence diameter, main shoot diameter, shoot and root biomass, and phosphorus concentration. Moreover, nitrogen and potassium concentrations were highest at 40% treatment. A positive increase in chlorophyllabut not chlorophyllbwas found by application of all levels of sugarcane compost compared to control plants.

关键词： Genetics   Carboxyls   Biosynthesis   Chemical structure   Chemical reactions  

摘要： Staphyloferrin B is a key siderophore secreted by Staphylococcus aureus to acquire ferric ions from a host during infection, and its biosynthetic pathway has been validated to develop efficient antibacterial agents. Herein, we report the crystal structure of AMP-bound SbnC from S. aureus (SaSbnC) as the first representative structure of type B synthetases in the biosynthesis of alpha-hydroxycarboxylate siderophores. While type B synthetases specifically use alpha-ketoglutarate (alpha-KG) as their carboxylic acid substrate, SaSbnC showed unique structural features in the substrate pocket compared with the type A and C synthetases. Screening of aKG analogues suggested that the hydrogen-bonding interaction between the alpha-carbonyl group of alpha-KG and residue Lys552 is a key determinant for the substrate selectivity of type B synthetases. Interestingly, citrate, the product of the tricarboxylic acid cycle and the substrate of type A synthetases, was found to inhibit the activity of SaSbnC with an IC(50 )value of 83 mu M by mimicking alpha-KG binding, suggesting a potential regulatory role of the tricarboxylic acid cycle, whose activity is under the control of the intracellular iron concentration, to SaSbnC and other type B synthetases. These results provide critical new information to understand the structure, function, and regulation of type B synthetases in the siderophore-based iron acquisition system employed by a large number of pathogenic microbes.

关键词： Oxidative stress   Gene expression   Histopathology   Cytochrome P450   Heat shock proteins  

摘要： The occurrence of Benzotriazole Ultraviolet Stabilizer-328 (BUV-328) in different environmental and biological matrices is of immediate environmental concern. In the present study, we evaluated the toxicity of BUV-328 in zebrafish liver tissues to understand the role of oxidative damage in hepatotoxicity. Adult zebrafish were exposed to 0.01,0.1 and 1 mg/L of BUV-328. At the end of 14, 28 and 42 days, liver tissues were examined for the responses of antioxidant enzymes, gene expression and histopathological alterations. The results indicated that superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities were elevated at concentrations of 0.1 and 1 mg/L on 14th and 28th day. Glutathione S-transferase (GST) activity and malondialdehyde (MDA) levels were elevated in all the treated groups. The transcriptional levels of genes encoding sod, cat, gpx and gst enzymes were increased at 14th day and then declined (except sod on 28th day). Moreover, transcription of cypla and hsp70 were up-regulated throughout the study period. Histopathological lesions such as hypertrophy, cellular and nuclear enlargement, cytoplasmic and nuclear degeneration, necrosis with pyknotic nuclei, lipid and cytoplasmic vacuolization and nuclear displacement to the periphery were found to be increased with the dose and exposure duration. In brief, our findings indicate that even a low dose of BUV-328 is toxic to induce oxidative stress and liver damage in zebrafish over a long period of exposure. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Mn-SOD   Heat stress   Wheat   Recombinant protein   ROS   Thermotolerance   Hydrogen peroxide   Transcript profiling   Homology   Domain profiling  

摘要： Heat stress causes oxidative bursts damaging the organelles and nascent proteins. Plants have inherited antioxidant defense system to neutralize the effect of reactive oxygen species. Superoxide dismutase provides first line of defense against the HS by regulating the accumulation of peroxide radicals inside the cells. Here, we report identification and cloning of putative manganese superoxide dismutase (Mn-SOD) gene of similar to 733 nt from wheat cv. HD2985 through de novo assembly. The gene was observed to localize on Chr 6D with a mitochondrial targeting peptide sequence and iron-imanganese domain. We predicted 147 homologs of Mn-SOD in eukaryotes with diverse speciation nodes. A recombinant Mn-SOD protein of similar to 25.5 kDa was purified through heterologous expression system. Kinetics assay of recombinant protein showed optimum pH of 8.0, optimum temperature of 35 degrees C and K-m and V-max values of 1.51 mu M and 9.45 U/mg proteins, respectively. Maximum expression and activity of Mn-SOD was observed in leaves from Raj3765, as compared to stem and spike during milky-ripe stage under differential HS. In gel activity assay showed the appearance of all the three isoforms of SOD in thermotolerant cv. under HS. Mn-SOD, being active at pivotal position, can be also used as potential biochemical marker in wheat breeding program. (C) 2020 Elsevier B.V. All rights reserved.