M2-like macrophages in the fibrotic liver protect mice against lethal insults through conferring apoptosis resistance to hepatocytes.

Acute injury in the setting of liver fibrosis is an interesting and still unsettled issue. Most recently, several prominent studies have indicated the favourable effects of liver fibrosis against acute insults. Nevertheless, the underlying mechanisms governing this hepatoprotection remain obscure. In the present study, we hypothesized that macrophages and their M1/M2 activation critically involve in the hepatoprotection conferred by liver fibrosis. Our findings demonstrated that liver fibrosis manifested a beneficial role for host survival and apoptosis resistance. Hepatoprotection in the fibrotic liver was tightly related to innate immune tolerance. Macrophages undertook crucial but divergent roles in homeostasis and fibrosis: depleting macrophages in control mice protected from acute insult; conversely, depleting macrophages in fibrotic liver weakened the hepatoprotection and gave rise to exacerbated liver injury upon insult. The contradictory effects of macrophages can be ascribed, to a great extent, to the heterogeneity in macrophage activation. Macrophages in fibrotic mice exhibited M2-preponderant activation, which was not the case in acutely injured liver. Adoptive transfer of M2-like macrophages conferred control mice conspicuous protection against insult. In vitro, M2-polarized macrophages protected hepatocytes against apoptosis. Together, M2-like macrophages in fibrotic liver exert the protective effects against lethal insults through conferring apoptosis resistance to hepatocytes

Optimization of Syringa oblata Lindl. Flower for Extraction of Polyphenols by Ultrasound-Assisted Deep Eutectic Solvents and Analysis of Antioxidant Activity

To establish an environmentally friendly and efficient method for extracting polyphenols from Syringa oblata Lindl. flowers and study the antioxidant activity of its polyphenols, this study used ultrasound-assisted deep eutectic solvents (UADESs) to extract polyphenols from Syringa oblata Lindl. flowers. Firstly, the choline chloride-malice acid, at a molar ratio of 1:1.5, and on the basis of the results of single-factor experiments, the extraction temperature, ultrasonic time, solid-liquid ratio and ultrasonic power, were selected as the key factors for optimization, and the extraction amount of polyphenols was used as the response value, and the Box-Behnken response surface method was used to optimize, and the scavenging ability of Syringa oblata Lindl. polyphenols on DPPH radicals and hydroxyl radicals was studied. The results showed that the optimized extraction parameters were extraction temperature of 60 ℃, ultrasonic time of 60 min, solid-liquid ratio 1:30 g/mL and ultrasonic power of 300 W, the polyphenol content could reach 52.19±0.13 mg/g, significantly higher than that of traditional extraction (60% ethanol, methanol) (P<0.05). Then in vitro antioxidant experiments showed that when the concentration of Syringa oblata Lindl. polyphenols was 2.0 mg/mL, the scavenging rates of DPPH and hydroxyl radicals were 93.28% and 52.57% respectively. This study would provide a green and efficient way for extracting polyphenols from Syringa oblata Lindl. using ultrasonic-assisted deep eutectic solvents and provide a theoretical foundation for the efficient extraction and practical utilization of Syringa oblata Lindl. polyphenols

Optimization of Cellulase-Assisted Ultrasound Extraction and Antioxidant Analysis of Flavonoids from Syringa oblata Leaves

To investigate the efficient method of total flavonoids from Syringa oblata leaves, this paper firstly used cellulase-assisted ultrasound method to extract flavonoids from four Syringa oblata leaves. The effects of cellulase dosage, pH, ultrasound time, ultrasound power, liquid-material ratio, temperature and ethanol volume fraction on the extraction rate of total flavonoids from Syringa pubescens Turcz. leaves were analyzed by single-factor experiments, and the best extraction process was obtained by applying response surface methodology optimization. The scavenging ability of Syringa oblata leaves flavonoids on DPPH and OH radicals was also examined in vitro as an antioxidant. The results showed that, the optimum extraction process was enzyme addition 2%, pH5.5, sonication time 40 min, sonication power 400 W, ethanol volume fraction 63%, temperature 56 ℃, liquid to material ratio 30:1 (mL/g), and under these conditions, the Syringa oblata flavonoids content was 32.21±0.16 mg/g, which was in proximity to the predicted value of 32.57 mg/g from the regression model. The results of antioxidant activity showed that the scavenging ability of the four Syringa oblata leaf flavonoids on DPPH was Syringa pubescens Turcz.>Syringa reticulata var. mamds huricq.>Syringa oblata var. affinis lingdelsh.>Syringa oblata Linal. The scavenging ability on OH was Syringa pubescens Turcz.>Syringa reticulata var. mamds huricq.> Syringa oblata Linal.>Syringa oblata var. affinis lingdelsh. The cellulase-assisted ultrasonication method can efficiently extract flavonoids from Syringa oblata leaves, and the flavonoids of Syringa oblata leaves have good antioxidant properties and have certain potential for development

Insight into the Stability of Cross-β Amyloid Fibril from VEALYL Short Peptide with Molecular Dynamics Simulation

Amyloid fibrils are found in many fatal neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, type II diabetes, and prion disease. The VEALYL short peptide from insulin has been confirmed to aggregate amyloid-like fibrils. However, the aggregation mechanism of amyloid fibril is poorly understood. Here, we utilized molecular dynamics simulation to analyse the stability of VEALYL hexamer. The statistical results indicate that hydrophobic residues play key roles in stabilizing VEALYL hexamer. Single point and two linkage mutants confirmed that Val1, Leu4, and Tyr5 of VEALYL are key residues. The consistency of the results for the VEALYL oligomer suggests that the intermediate states might be trimer (3-0) and pentamer(3-2). These results can help us to obtain an insight into the aggregation mechanism of amyloid fibril. These methods can be used to study the stability of amyloid fibril from other short peptides

Peptide Fragmentation and Amino Acid Quantification by Mass Spectrometry

Research presented in this dissertation falls into two parts: fragmentation mechanisms of peptide and fragmentation mechanism of amino acid derivatives. The study of peptide fragmentation may help to improve protein identification by incorporating the rules governing this process into search algorithms. This study elucidates the chemical 'rules' governing peptide dissociation. It is believed that these 'rules' can be incorporated into searching algorithms to achieve better protein identification. The present study focuses on the effects of different amino acids on fragmentation. Amino acids with a wide range of different chemical and physical properties are investigated, including amino acids with hydrophilic side chains, amino acids with aliphatic side chains and amino acids without side chains. It can be concluded from the present studies that the different amino acid properties have great influence on the peptide fragmentation and spectrum appearance.The study of fragmentation mechanisms of amino acid derivatives is another focus of this dissertation. Based on the fragmentation mechanism study, a quantification method was developed. The method can distinguish glutamine with 15N-label at N-terminal amine vs the side chain even if they have same molecular weight. Ammonia metabolism was successfully monitored by feeding mosquitoes with isotope-labeled compounds and subsequently measuring the amount of the labeled amino acids. This method demonstrates the power of mass spectrometry in metabolism studies

Efficient Recovery of Penicillin G by a Hydrophobic Ionic Liquid

Penicillin G is a widely used antibiotic, but the traditional volatile organic solvent extraction causes serious environmental problems. In this work, a hydrophobic ionic liquid ([Bmim]PF6) was developed as a new extraction agent for recovery of penicillin G from aqueous solutions. The extraction efficiency and the partition coefficient of penicillin G were used as the indexes to evaluate the IL extraction ability. Key factors affecting the effectiveness of recovery, such as the pH of the aqueous solution, the initial concentration of penicillin G, and the IL-to-aqueous solution volume ratio, were investigated to determine the optimal conditions. The results showed that the pH of the aqueous phase strongly influenced the success of the extraction. The optimal pH value, phase ratio, and penicillin concentration were 1.5-2.0, 1.5/1 to 2.0/ 1, and 3.00-5.00 X 10(4) units/mL, respectively, whereby the partition coefficient and extraction efficiency were more than 30 and 91%, respectively. The extraction mechanism was explored by analyzing the chemical bonds using spectrographic analysis. Preliminary results indicated that penicillin G can be effectively extracted from fermentation broth by [Bmim]PF6 with extraction efficiencies of &gt;87%. In addition, a higher selectivity and a much lower extent of emulsification were achieved by [Bmim]PF6 compared to those of butyl acetate. It demonstrates that the IL-based extraction strategy developed in this work is promising and effective, and as a result, the development of an IL-based extraction process for the recovery of penicillin G is straightforwardly envisaged

Response of Water Radiation Utilization of Summer Maize to Planting Density and Genotypes in the North China Plain

Increasing the planting density of summer maize to improve the utilization efficiency of limited soil and water resources is an effective approach; however, how the leaf water-use efficiency (WUEL), yield, and RUE respond to planting density and genotypes remains unclear. A 2-year field experiment was performed in the North China Plain (NCP) to investigate the effects of planting density (high, 100,000 plants ha−1; medium, 78,000 plants ha−1; and low, 56,000 plants ha−1) and genotypes (Zhengdan 958 and Denghai 605) on the leaf area index (LAI), photosynthetic characteristics, dry-matter accumulation, WUEL, and RUE of maize. The objective was to explore the effect of density and genotype on the WUEL and RUE of maize. Increasing planting density boosted LAI, light interception, dry-matter accumulation, and spike number but reduced the chlorophyll content, net photosynthetic rate, transpiration rate, and 1000-kernel weight. Both high and low planting densities were averse to RUE and yield. Zhengdan 958 increased the WUEL by 19.45% compared with Denghai 605, but the RUE of Denghai 605 was 18.19% higher than Zhengdan 958, suggesting that Denghai 605 had a greater production potential as the planting density increased. Our findings recommend using 78,000 plants ha−1 as the planting density with Denghai 605 to maintain summer maize yields in the NCP