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BACKGROUND: Agaricus bisporus with a completely white appearance is popular with consumers. However, A. bisporus is susceptible to senescence and spoilage, which results in browning and oxidative tissue damage, with limited shelf life. This study investigated the effects of shortwave ultraviolet (UV‐C, 1.0 kJ m−2) irradiation on quality features, enzymatic browning, and defense properties of A. bisporus stored at 4 °C for 21 days. RESULTS: After storage, UV‐C irradiated A. bisporus had increased quality of sensory, color and hardness characteristics; it exhibited higher content of total phenolic, brown melanin precursors, including γ‐glutaminyl‐4‐hydroxybenzene, γ‐glutaminyl‐3,4‐dihydroxybenzene and tyrosine, lower accumulation of malondiadehyde, hydrogen peroxide and superoxide radical, and maintained membrane integrity in comparison to control samples. Besides, A. bisporus treated by UV‐C showed lower degree of browning and higher level of self‐defense capacity, which may be ascribed to the enhancement in activities of superoxide dismutase, catalase, phenylalanine ammonia lyase, chitinase and β‐1,3‐glucanase activity, while inhibiting polyphenol oxidase activity during storage. CONCLUSION: These results indicate that the higher self‐defense capacity with UV‐C treatment might be the mechanism associated with the delay of senescence in Agaricus bisporus. Therefore, UV‐C treatment is suggested as a potential practical application in mushrooms. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study aims to investigate the causal relationship between the Turkish stock market returns, namely XU100, and foreign exchange rates, namely USD/TRY and EUR/TRY, in Turkey using the wavelet coherence approach. In this study, we focus on the period from April 2000 to March 2019. Our findings reveal the following: (i) While we identify substantial volatility in the exchange rate during the 2000 November (banking crisis), 2001 February (economic crisis), and 2018 July (exchange rate crisis) periods, significant volatility was observed in the Turkish stock market during the 2000 banking crisis, 2001 economic crisis, and 2008 global crisis periods; (ii) There is a negative correlation between the Turkish stock market and foreign exchange rates at different frequencies over the selected sample period; (iii) A unidirectional causality runs from the Turkish stock market to foreign exchange rates between 2000 and 2004 at a scale of 4 months and between 2008 and 2012 at a scale of 32 months; (iv) Although inconsistent results are observed for the models of USD/TRY‐XU100 and EUR/TRY‐XU100, our empirical results show that the correlations between USD/TRY and XU100 are stronger than between EUR/TRY and XU100. [ABSTRACT FROM AUTHOR]

Summary: Shiitake mushrooms contain free phenolics (FPs) and bound phenolics (BPs). BPs embedded in mushrooms are generally neglected and underestimated. Methods of hydrolysis with acid, base and their combination in different sequences were developed to release BPs. The contents, compositions and antioxidant capacities of FPs and BPs were investigated. Results found that BPs yielded with combining base and acid hydrolysis received the highest value (25.67 mg gallic acid equivalents (GAE)/100 g dry weight (DW)), which was higher than FPs (20.62 mg GAE/100 g DW). LC‐ESI‐QqQ‐MS/MS analysis demonstrated that gallic acid, protocatechuic acid, caffeic acid, and ferulic acid presented in all BPs fractions, whereas hesperidin, luteolin, quercetin, and cinnamic acid were affected by hydrolysis methods and procedures. BPs fractions with higher phenolic content showed strong antioxidant capacities. These results demonstrate the importance of BPs and can be applied to enhance the amount and bioavailability of BPs from shiitake mushrooms and other foods. [ABSTRACT FROM AUTHOR]

BACKGROUND Button mushrooms with completely white appearance are popular with consumers. However, button mushrooms are susceptible to infection with Pseudomonas tolaasii, which results in browning. This study evaluates the effects of ultraviolet‐C (UV‐C) treatment on the inactivation of P. tolaasii in vitro and in vivo and on the physiological and chemical changes of button mushrooms during storage for 21 days at 4 °C. RESULTS: UV‐C doses of 0.5 to 9.0 kJ m−2 resulted in 3.91–6.26 log CFU mL−1 reduction of P. tolaasii populations in vitro, and UV‐C treatment reduced P. tolaasii populations inoculated on mushroom cap surfaces and browning severity. Moreover, P. tolaasii increased polyphenol oxidase (PPO) activity, and decreased phenylalanine ammonia‐lyase (PAL) activity, the accumulation of phenolics and contents of brown melanin precursors, including γ‐l‐glutaminyl‐4‐hydroxybenzene (GHB), γ‐l‐glutaminyl‐3,4‐dihydroxybenzene (GDHB), and tyrosine in button mushrooms. UV‐C treatment was found to reduce the negative changes due to P. tolaasii infection. CONCLUSION: These results indicated that the application of UV‐C treatment inhibited browning, inactivated P. tolaasii and reduced P. tolaasii – associated chemical and enzymatic changes of button mushrooms. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Controlled peptide assembly is an important approach for the synthesis of materials with diverse functions, which opened up new frontiers in polymer science. Herein, we have qualitatively evaluated the morphological changes of the self‐assembly heptapeptide "Fmoc‐AEAEAEA‐CONH2" under various experimental conditions by transmission electron microscopy. The results showed that the morphology of the self‐assembled heptapeptide were found to be strongly influenced by the temperature, pH and solvents. And the heptapeptide can form two assemblies, nanofibers and cubes, depending on the kinetic parameters during the fabrication. It was concluded that the rebalance of molecular interactions such as hydrophobic interactions, hydrogen bonding and electrostatic interactions between peptides are responsible for the conversion of morphology. Additionally, the two assemblies could be utilized as the β‐glucosidase mimics, and the catalytic activity of the hydrolases mimics followed the density of active sites outside the assemblies. This finding provided a new perspective to understanding the process of self‐assembling and the potential relationship between block architectures and the generation of efficient artificial enzymes. [ABSTRACT FROM AUTHOR]

Background & Aims: Serum adipocyte fatty acid‐binding protein (A‐FABP) is closely correlated to metabolic disorders such as obesity and insulin resistance (IR). Non‐alcoholic fatty liver disease (NAFLD) is a typical feature of IR in the liver. The aim of this study was to explore the relationship between serum A‐FABP levels and NAFLD. Methods: The study enrolled 728 subjects with normal glucose tolerance from communities. Serum A‐FABP levels were measured using a sandwich enzyme‐linked immunosorbent assay. The liver fat content was assessed by ultrasonography. The fatty liver index (FLI) was calculated to quantify the degree of liver steatosis. The upper quartile of homoeostasis model assessment‐insulin resistance (HOMA‐IR) in the total population was defined as IR. Adipose tissue insulin resistance (Adipo‐IR) was calculated to evaluate the impaired suppression of lipolysis in IR. Results: Serum A‐FABP levels were significantly higher in subjects with NAFLD than in those without (P < 0.01). Moreover, subjects with IR had higher levels of A‐FABP than those without (P < 0.01). The proportion of IR or NAFLD and the levels of fasting free fatty acid (FFA) or Adipo‐IR displayed an upward trend as A‐FABP increased (P for trend < 0.05). After adjusting for gender, age, body fat, metabolic factors and liver enzymes, A‐FABP was independently correlated with NAFLD (P < 0.01). A‐FABP was a positive determinant of FLI (P = 0.006). Conclusions: Serum A‐FABP levels were significantly elevated in NAFLD patients among a population with normal glucose tolerance. Serum A‐FABP levels were independently correlated with NAFLD after adjusting for confounding factors. [ABSTRACT FROM AUTHOR]

Magnetic materials were recently developed for sludge disposal because of their advantages. However, the role of magnetic materials in the process of anaerobic digestion of municipal dewatered sludge remains unclear. The aim of this present study is to investigate the magnetic effect factors such as static magnetic field, magnetic nanoparticles, and ordinary magnetic particles on the anaerobic digestion of municipal dewatered sludge. In addition, the biogas production variations and relevant physicochemical properties of municipal dewatered sludge under anaerobic digestion are also evaluated by adding anaerobic bacteria. Results indicated that the magnetic nanoparticles are superior to both ordinary magnetic particles and static magnetic field at total biogas production; moreover, the aerobic bacteria could shorten the duration of anaerobic digestion. For the sludge dewatering, the organic matter degradation rate, chemical oxygen demand degradation rate, and dewatering rate under the treatment condition with magnetic nanoparticles are 32.1%, 87.1%, and 70.9%, respectively. It is suggested that the magnetic nanoparticles are much suitable for sludge dewatering than ordinary magnetic particles. As combined with bacteria, magnetic nanoparticles can effectively increase gas output, methane content, and shorten the anaerobic digestion period. © 2018 American Institute of Chemical Engineers Environ Prog, 38: 374–379, 2019 [ABSTRACT FROM AUTHOR]

Summary: Recent studies have shown that circulating fibroblast growth factor (FGF) 23 and vitamin D levels are closely correlated with insulin resistance. The aim of this study was to investigate the relationship among serum FGF 23 levels, serum 25‐hydroxyvitamin D [25(OH)D] levels, and non‐alcoholic fatty liver disease (NAFLD) in Chinese patients with type 2 diabetes mellitus (T2DM). This study enrolled 331 hospitalized T2DM patients (209 patients with NAFLD and 122 patients without NAFLD). Serum FGF23 levels were measured using a sandwich enzyme‐linked immunosorbent assay. Serum 25(OH)D levels were determined by an electrochemiluminescence immunoassay. NAFLD was diagnosed by hepatic ultrasound, and the fatty liver index (FLI) was calculated to quantify hepatic steatosis. Results showed that T2DM patients with NAFLD had significantly higher serum FGF23 levels (44.17 [37.92‐51.30] pg/mL vs 40.21 [34.07‐48.33] pg/mL, P = .002), but lower serum 25(OH)D levels (16.43 [12.70‐21.37] ng/mL vs 19.59 [13.78‐26.26] ng/mL, P = .002) than those without NAFLD. Moreover, the incidence rate of NAFLD increased with increasing serum FGF23 levels and decreased with increasing 25(OH)D levels (both P < .05). Logistic regression analysis showed that both serum FGF23 and 25(OH)D levels were independent factors for NAFLD (both P < .05). Furthermore, a multiple stepwise regression analysis also revealed that both serum FGF23 and 25(OH)D levels were independently correlated with FLI (both P < .01). In conclusion, both high FGF23 and low vitamin D levels showed an independent relationship with NAFLD in Chinese T2DM patients, indicating that FGF23 and vitamin D function via different regulatory pathways in the liver. [ABSTRACT FROM AUTHOR]

Background Transforming growth factor ( TGF) β signalling pathway plays a crucial role in liver regeneration following partial hepatectomy in mice. Evidence demonstrated that β-2 Spectrin is involved in TGFβ/Smad signalling pathway as a Smad3/4 adaptor protein. Aim The aim of this study was to explore the role of β-2 Spectrin in hepatocyte proliferation. Methods β-2 Spectrin expression was evaluated in mice receiving partial hepatectomy. The effect of si RNA against β-2 Spectrin on hepatocyte proliferation was determined. The interaction between TGFβ/Smad and PI3K/ Akt signalling was investigated. Results Hepatic β-2 Spectrin decreased dramatically 2 days after 70% hepatectomy in mice. In AML-12 cells, hepatocyte proliferation was inhibited after the stimulation of TGF β1 and a reduction in β-2 Spectrin mediated by siRNA resulted in increase in proliferative response. Confocal results revealed that β-2 Spectrin represented a key regulator in TGFβ/Smad signalling through controlling Smad3/4 subcellular localization. Moreover, Alternation of Akt phosphorylation led to the change in subcellular localization of Smad2, 3, 4 and β-2 Spectrin, A reduction in Smad2, 3 and 4 mediated by siRNA resulted in the induction of pAkt expression. Conclusions These findings reveal that β-2 Spectrin plays a crucial role in hepatocyte proliferation, which contributes to liver regeneration following hepatectomy in mice. In addition, PI3K/ Akt is involved in TGFβ/Smad signalling pathway through the interaction with Smad proteins and β-2 Spectrin. [ABSTRACT FROM AUTHOR]

Transforming growth factor (TGF) β1 plays a critical role in liver fibrosis. Previous studies demonstrated embryonic liver fodrin (ELF), a β-spectrin was involved in TGF-β/Smad signalling pathway as Smad3/4 adaptor. Here we investigate the role of ELF in pathogenesis of liver cirrhosis. In carbon tetrachloride (CCl4)-induced mice model of liver cirrhosis, ELF is up-regulated in activated hepatic stellate cells (HSCs), and down-regulated in regenerative hepatocytes of cirrhotic nodules. In activated HSCs in vitro, reduction of ELF expression mediated by siRNA leads to the inhibition of HSC activation and procollagen I expression. BrdU assay demonstrates that down-regulation of ELF expression does not inhibit proliferation of activated HSCs in vitro. Immunostaining of cytokeratin 19 and Ki67 indicates that regenerative hepatocytes in cirrhotic liver are derived from hepatic progenitor cells (HPC). Further study reveals that HPC expansion occurs as an initial phase, before the reduction of ELF expression in regenerative hepatocytes. Regenerative hepatocytes in cirrhotic liver show the change in proliferative activity and expression pattern of proteins involved in G1/S transition, which suggests the deregulation of cell cycle in regenerative hepatocytes. Finally, we find that ELF participates in TGF-β/Smad signal in activated HSCs and hepatocytes through regulating the localization of Smad3/4. These data reveal that ELF is involved in HSC activation and the formation of regenerative nodules derived from HPC in cirrhotic liver. [ABSTRACT FROM AUTHOR]

Background: Study on viruses has greatly benefited from visualization of viruses tagged with green fluorescent protein (GFP) in living cells. But GFP tag, as a large inserted fragment, is not suitable for labelling Hepatitis B virus (HBV) that is a compact virion with limited internal space., Aim: To visualize HBV in living cells, we constructed several recombinant HBV fluorescently labelled with biarsenical dye to track the behaviour of HBV in the cytoplasm of infected cells., Methods: By mutagenesis, a smaller size tetracysteine (TC) tag (C-C-P-G-C-C) that could be bound with a biarsenical fluorescent dye was genetically inserted at different cell epitopes of HBV core protein expressed in transfected cells., Result: Confocal microscopy and transmission electron microscopy (TEM) observations showed that TC-tagged core proteins bound with biarsenical dye could specifically fluoresce in cells and be incorporated into nucleocapsid to form fluorescent virions. The recombinant fluorescent HBV virions retained their infectivity as wild-type ones. Moreover, tracking of fluorescent HBV particles in living cells reveals microtubule-dependent motility of the intracellular particles., Conclusion: To the best of our knowledge, this is the first time to generate fluorescent HBV virions with biarsenical labelling and to visualize their trafficking in living cells. The fluorescent HBV may become one highly valuable tool for further studying detailed dynamic processes of HBV life cycle and interaction of HBV with host in live-imaging approach., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Transforming growth factor (TGF) β signalling pathway plays a crucial role in liver regeneration following partial hepatectomy in mice. Evidence demonstrated that β-2 Spectrin is involved in TGFβ/Smad signalling pathway as a Smad3/4 adaptor protein., Aim: The aim of this study was to explore the role of β-2 Spectrin in hepatocyte proliferation., Methods: β-2 Spectrin expression was evaluated in mice receiving partial hepatectomy. The effect of siRNA against β-2 Spectrin on hepatocyte proliferation was determined. The interaction between TGFβ/Smad and PI3K/Akt signalling was investigated., Results: Hepatic β-2 Spectrin decreased dramatically 2 days after 70% hepatectomy in mice. In AML-12 cells, hepatocyte proliferation was inhibited after the stimulation of TGF β1 and a reduction in β-2 Spectrin mediated by siRNA resulted in increase in proliferative response. Confocal results revealed that β-2 Spectrin represented a key regulator in TGFβ/Smad signalling through controlling Smad3/4 subcellular localization. Moreover, Alternation of Akt phosphorylation led to the change in subcellular localization of Smad2, 3, 4 and β-2 Spectrin, A reduction in Smad2, 3 and 4 mediated by siRNA resulted in the induction of pAkt expression., Conclusions: These findings reveal that β-2 Spectrin plays a crucial role in hepatocyte proliferation, which contributes to liver regeneration following hepatectomy in mice. In addition, PI3K/Akt is involved in TGFβ/Smad signalling pathway through the interaction with Smad proteins and β-2 Spectrin., (© 2012 John Wiley & Sons A/S.)