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231.
Indigenous Saccharomyces cerevisiae, as a new and useful tool, can be used in fermentation to enhance the aroma characteristic qualities of the wine-production region. In this study, we used indigenous S. cerevisiae L59 and commercial S. cerevisiae FX10 to ferment Prince (a new hybrid variety from Lion Winery) wine, detected the basic physicochemical parameters and the dynamic changes of fungal communities during fermentation, and analyzed the correlations between fungal communities and volatile compounds. The results showed that the indigenous S. cerevisiae L59 could quickly adapt to the specific physicochemical conditions and microbial ecology of the grape must, showing a strong potential for winemaking. Compared with commercial S. cerevisiae FX10, the wine fermented by indigenous S. cerevisiae L59 contained more glycerol and less organic acids, contributing to a rounder taste. The results of volatile compounds indicated that the indigenous S. cerevisiae L59 had a positive effect on adding rosy, honey, pineapple and other sweet aroma characteristics to the wine. Overall, the study we performed showed that selection of indigenous S. cerevisiae from the wine-producing region as a starter for wine fermentation is conducive to improving the aroma profile of wine and preserving the aroma of the grape variety.  相似文献   
232.
The clinical application of gentamicin may lead to acute kidney injury (AKI), and the nephrotoxicity of gentamicin is related to the pathological mechanism of several oxidative and inflammatory cytokines. Plant-derived essential oils have good anti-inflammatory and antioxidant properties. This study aimed to clarify the protective effect of Amomum tsao-ko essential oils (AOs) on gentamicin-induced AKI in rats and its possible mechanism. The rat AKI model was induced by intraperitoneal injection of gentamicin. After 14 days of oral AO treatment, the renal function and pathological changes of the kidney tissues were evaluated, and the level of kidney tissue oxidative stress was detected. The content of inflammatory cytokines was measured by ELISA. The expression of ERK1/2, JNK1/2, p38, NF-κB, caspase-3, and Bax/Bcl-2 proteins were estimated by Western blot analysis. The results showed that taking AO reduced the contents of serum urea and creatinine in AKI rats and improve the pathological changes and oxidative stress of the kidney tissue in rats. At the same time, AO reduced inflammation and apoptosis during AKI by regulating the MAPK pathway. The data show that AO has a protective effect on the kidneys and may be a potential drug for treating kidney injury.  相似文献   
233.
In recent years, the prevalence of diabetes is on the rise, globally. Resistant starch (RS) has been known as a kind of promising dietary fiber for the prevention or treatment of diabetes. Therefore, it has become a hot topic to explore the hypoglycemic mechanisms of RS. In this review, the mechanisms have been summarized, according to the relevant studies in the recent 15 years. In general, the blood glucose could be regulated by RS by regulating the intestinal microbiota disorder, resisting digestion, reducing inflammation, regulating the hypoglycemic related enzymes and some other mechanisms. Although the exact mechanisms of the beneficial effects of RS have not been fully verified, it is indicated that RS can be used as a daily dietary intervention to reduce the risk of diabetes in different ways. In addition, further research on hypoglycemic mechanisms of RS impacted by the RS categories, the different experimental animals and various dietary habits of human subjects, have also been discussed in this review.  相似文献   
234.
The application of crumb rubber from end-of-life tires and waste cooking oil (WCO) in road pavements is of significant importance from an economic and environmental viewpoint. However, the incorporation of crumb rubber greatly shortens the allowable construction time of epoxy asphalt binders due to the high viscosity of the epoxy asphalt rubber (EAR) binder and poor compatibility between crumb rubber and asphalt binder. To lower the viscosity of asphalt rubber, extend the allowable construction time and improve the compatibility of EAR binder, waste cooking oil (WCO) was introduced. The effect of WCO on the viscosity–time behavior, thermal stability, dynamic modulus, glass transitions, crosslink density, damping ability, compatibility, mechanical properties and phase separation of WCO-modified EAR binders was investigated by using the Brookfield viscometer, thermogravimetric analysis, dynamic mechanical analysis, universal testing machine and laser confocal microscopy. The test results demonstrated that the incorporation of WCO declined the viscosity and extended the allowable construction time of the unmodified EAR binder. The inclusion of WCO improved the compatibility between asphalt and crumb rubber and the damping ability and elongation at the break of the unmodified EAR binder. The presence of WCO had a marginal effect on the thermal stability of the unmodified EAR binder. Confocal microscopy observation revealed that asphalt rubber particles aggregated in the epoxy phase of the unmodified EAR binder. With the inclusion of WCO, co-continuous asphalt rubber particles became more spherical.  相似文献   
235.
236.
Sample preparation remains both a challenging and time-consuming process in the field of bioanalytical chemistry. Many traditional techniques often require multi-step processes, which can introduce additional errors to the analytical method. Given the complexity of many biological matrices, thorough analyte extraction presents a major challenge to researchers. In the present study, a headspace solid-phase microextraction (HS-SPME) coupled with a GC/Q-ToF-MS method, was developed to quantify in vitro metabolism of β-caryophyllene by both human liver microsome (HLM) and S9 liver fractions. Validation of the method was demonstrated both in terms of linearity (R2 = 0.9948) and sensitivity with a limit of detection of 3 ng/mL and a limit of quantitation of 10 ng/mL. In addition, the method also demonstrated both inter- and intra-day precision with the relative standard deviation (RSD) being less than 10% with four concentrations ranging from 50–500 ng/mL. Since this method requires no solvents and minimal sample preparation, it provides a rapid and economical alternative to traditional extraction techniques. The method also eliminates the need to remove salts or buffers, which are commonly present in biological matrices. Although this method was developed to quantify in vitro metabolism of one analyte, it could easily be adapted to detect or quantify numerous volatiles and/or semi-volatiles found in biological matrices.  相似文献   
237.
In this work, manganese (Mn)-doped YFeO3, i.e., YFMxO powders with 0 ≤ x ≤ 0.1, was synthesized by a hydrothermal method to study the influences of doping on its structural, morphological, optical, magnetic, and local electrical properties. The experimental results show that all the samples exhibit an orthorhombic structure with space group Pnma. Refined structure parameters are presented. Morphology images show the shape evolution from layered to multilayered with increasing Mn content. Infrared spectra reveal the characteristic vibrations of the obtained YFMxO samples. From the magnetic study, an increased magnetic moment in the range of 0 ≤ x ≤ 0.075 is observed. The Fe and Y K-edge local structure studies indicate that the valency of Fe and Y is mainly found in the trivalent state, which also indicates that the substitution of Mn ions not only affects the nearest neighbor atomic shell of Fe but also affects the nearest neighbor’s local structure of Y atoms. Our results show that the addition of Mn exhibits an evident influence on the local structural and magnetic properties.  相似文献   
238.
Hydrogen sulfide (H2S) as small molecular signal messenger plays key functions in numerous biological processes. The imaging detection of intracellular hydrogen sulfide is of great significance. In this work, a ratiometric fluorescent probe BH based on an asymmetric BODIPY dye for detection of H2S was designed and synthesized. After the interaction with hydrogen sulfide, probe display colorimetric and ratiometric fluorescence response, with its maximum emission fluorescence wavelength red-shifted from 542 nm to 594 nm, which is attributed to the sequential nucleophilic reaction of H2S leading to enhanced molecular conjugation after ring formation of the BODIPY skeleton. A special response mechanism has been fully investigated by NMR titration and MS, so that the probe has excellent detection selectivity. Furthermore, probe BH has low cytotoxicity and fluorescence imaging experiments indicate that it can be used to monitor hydrogen sulfide in living cells.  相似文献   
239.
Polymer electrolytes (PEs) with high flexibility, low cost, and excellent interface compatibility have been considered as an ideal substitute for traditional liquid electrolytes for high safety lithium metal batteries (LMBs). Nevertheless, the mechanical strength of PEs is generally poor to prevent the growth of lithium dendrites during the charge/discharge process, which seriously restricts their wide practical applications. Herein, a mechanical robust ZIF-8/epoxy composite electrolyte with unique pore structure was prepared, which effectively inhibited the growth of lithium dendrites. Meanwhile, the in situ growth of ZIF-8 in porous epoxy matrix can promote the uniform flux and fast transport of lithium ions. Ultimately, the optimal electrolyte shows high ionic conductivity (2.2 × 10−3 S cm−1), wide electrochemical window (5 V), and a large Li+ transference number (0.70) at room temperature. The Li||NCM811 cell using the optimal electrolyte exhibits high capacity and excellent cycling performance (83.2% capacity retention with 172.1 mA h g−1 capacity retained after 200 cycles at 0.2 C). These results indicate that the ZIF-8/epoxy composite electrolyte is of great promise for the application in LMBs.  相似文献   
240.
Protein arginine methyltransferase 5 (PRMT5) is a popular anticancer target that regulates histone or nonhistone methylation and is linked to the development and poor prognosis of non-small cell lung cancer. PRMT5 inhibitors have shown great promise in clinical trials as a cancer therapy. However, most inhibitors reported recently act in a SAM-competitive mode and lack structural diversity. In this paper, a novel non-SAM inhibitor, 3039-0164, was discovered by the structure-based virtual screening method. The binding mechanism of 3039-0164 to PRMT5 was revealed via molecular docking and molecular dynamics simulations. 3039-0164 inhibited PRMT5 enzymatic activity, downregulated the expression of PRMT5 downstream target genes (FGFR3 and eIF4E), and blocked the activation of the PI3K/AKT/mTOR and ERK signaling pathways. The discovery of 3039-0164 provides precise and creative hit compounds for the design optimization of PRMT5 lead compounds in non-small cell lung cancer.  相似文献   
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