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1.
Food Chem ; 371: 131200, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34624741

RESUMO

Fresh shiitake (Lentinus edodes) is prone to brown, pileus-opening and flavor-loss during storage. Therefore, it is important to find an effective preservation method for fresh shiitake. Negative air ions (NAI) are negatively-charged molecules or atoms in the air, and can affect the physiological metabolism of live cells and be conveniently used with low cost. In this study, NAI treatment was performed at different times and the physico-chemical characteristics, microstructure, membrane potential and energy metabolism of shiitake were determined during storage. Results showed that NAI treatment for 40 min could reduce 29% of browning index and maintain the hardness of shiitake. NAI treatment groups had higher content of sweetness amino acids, umami amino acids, 5'-IMP, eight-carbon alcohols compounds and cyclic sulfides compounds than the control, and comprehensive quality of the group being treated for 40 min was the best. The mitochondria of shiitake swelled and the membrane potential decreased after being treated by NAI. However, NAI treatment for 40 min could improve the contents of ATP and ADP, maintain a relatively stable energy charge level, and promote energy utilization of shiitake during storage. The results demonstrated that NAI treatment had the potential to improve the quality shiitake during storage.

2.
Hepatology ; 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34482560

RESUMO

BACKGROUND AND AIMS: Nonalcoholic steatohepatitis (NASH) is a complicated disease characterized by hepatocyte steatosis, inflammation infiltration, and liver fibrosis. Accumulating evidence suggests that the innate immunity plays a key role in NASH progression. Here, we aimed to reveal the role of melanoma-differentiation-associated gene 5 (MDA5, also known as Ifih1), a conventional innate immune regulator upon viral infection, in the progression of NASH and investigate its underlying mechanism. APPROACH AND RESULTS: We first examined the expression of MDA5 and found that MDA5 was markedly downregulated in the livers with NASH in human individuals and mice models. MDA5 overexpression significantly inhibited the free fatty acid (FFA) induced lipid accumulation and inflammation in hepatocyte in vitro, while MDA5 knockdown promotes hepatocyte lipotoxicity. Using hepatocyte-specific Mda5 gene knockout and transgenic mice, we found that diet induced hepatic steatosis, inflammation and liver fibrosis were markedly exacerbated by Mda5 deficiency but suppressed by Mda5 overexpression. Mechanistically, we found that the activation of ASK1-MAPK pathway was significantly inhibited by MDA5 but enhanced by MDA5 deletion. We further validated that MDA5 directly interacted with ASK1 and suppressed its N-terminal dimerization. Importantly, blockage of ASK1 with adenovirus expressing dominant negative ASK1 (dnASK1) obviously reversed the lipid accumulation and ASK1 pathway activation when Mda5 knockout. CONCLUSIONS: These data indicate that MDA5 is an essential suppressor in NASH, the findings support MDA5 as a novel regulator of ASK1 and a promising therapeutic target for NASH.

3.
Protein Pept Lett ; 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34493183

RESUMO

In recent years, bioactive peptide drugs as new drugs have attracted growing attention due to the increasing difficulty in developing new drugs with novel chemical structures. In addition, many diseases are linked to excessive oxidation in the human body. Therefore, the role of peptides with antioxidant activity in counteracting diseases related to oxidative stress is worth exploring. Amphibians are a major repository for bioactive peptides that protect the skin from biotic and abiotic stresses such as microbial infection and radiation injury. We characterized the first amphibian-derived gene-encoded antioxidant peptides in 2008. Since then, a variety of antioxidant peptides have been detected in different amphibian species. In this work, the physicochemical properties of antioxidant peptides identified from amphibians are reviewed for the first time, particularly acquisition methods, amino acid characteristics, antioxidant mechanisms, and application prospects. This review should provide a reference for advancing the identification, structural analysis, and potential therapeutic value of natural antioxidant peptides.

4.
Soft Matter ; 17(36): 8308-8313, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34550160

RESUMO

Multi-functional materials have received wide attention due to their potential applications in various fields; therefore, developing a simple and easy strategy for the preparation of multi-functional materials is an interesting issue. In this work, a novel supramolecular gel, TP-QG, has been successfully constructed via the assembly of a simple methoxyl-pillar[5]arene host (TP) and a tripodal (tri-pyridine-4-yl)-amido-benzene guest (Q). Interestingly, TP-QG could act as a multi-functional material and showed strong fluorescence, good self-healing, host-guest stimuli-responsiveness and conductive properties. Due to these properties, TP-QG shows a fascinating application prospect. For instance, TP-QG could exhibit ultrasensitive fluorescence response for Fe3+ and F- in water via the fluorescence "ON-OFF-ON" pathway; the lowest detection limit (LOD) of TP-QG for Fe3+ was 2.32 × 10-10 M and the LOD of TP-QG-Fe for F- was 4.30 × 10-8 M. These properties permit TP-QG to act as not only a Fe3+ and F- sensor, but also an "ON-OFF-ON" fluorescence display material and an efficient logic gate. Meanwhile, the xerogel of TP-QG could remove Fe3+ from water, and the adsorption ratio was 98.68%; the xerogel of TP-QG-Fe could also remove F- from water; the removal ratio was about 87.92%. This work provides a feasible way to construct multi-functional smart materials by host-guest assembly.

5.
Cell Metab ; 33(10): 1943-1956.e2, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34478633

RESUMO

Metabolic dysfunction is becoming a predominant risk for the development of many comorbidities. Ischemic heart disease (IHD) still imposes the highest disease burden among all cardiovascular diseases worldwide. However, the contributions of metabolic risk factors to IHD over time have not been fully characterized. Here, we analyzed the global disease burden of IHD and 15 associated general risk factors from 1990 to 2019 by applying the methodology framework of the Global Burden of Disease Study. We found that the global death cases due to IHD increased steadily during that time frame, while the mortality rate gradually declined. Notably, metabolic risk factors have become the leading driver of IHD, which also largely contributed to the majority of IHD-related deaths shifting from developed countries to developing countries. These findings suggest an urgent need to implement effective measures to control metabolic risk factors to prevent further increases in IHD-related deaths.

6.
Cell Metab ; 33(10): 2059-2075.e10, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34536344

RESUMO

Myocardial ischemia-reperfusion (MIR) injury is a major cause of adverse outcomes of revascularization after myocardial infarction. To identify the fundamental regulator of reperfusion injury, we performed metabolomics profiling in plasma of individuals before and after revascularization and identified a marked accumulation of arachidonate 12-lipoxygenase (ALOX12)-dependent 12-HETE following revascularization. The potent induction of 12-HETE proceeded by reperfusion was conserved in post-MIR in mice, pigs, and monkeys. While genetic inhibition of Alox12 protected mouse hearts from reperfusion injury and remodeling, Alox12 overexpression exacerbated MIR injury. Remarkably, pharmacological inhibition of ALOX12 significantly reduced cardiac injury in mice, pigs, and monkeys. Unexpectedly, ALOX12 promotes cardiomyocyte injury beyond its enzymatic activity and production of 12-HETE but also by its suppression of AMPK activity via a direct interaction with its upstream kinase TAK1. Taken together, our study demonstrates that ALOX12 is a novel AMPK upstream regulator in the post-MIR heart and that it represents a conserved therapeutic target for the treatment of myocardial reperfusion injury.

7.
Hepatology ; 2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34272738

RESUMO

BACKGROUND AND AIMS: NAFLD is the most prevalent chronic liver disease worldwide, but no effective pharmacological therapeutics are available for clinical use. NASH is the more severe stage of NAFLD. During this progress, dysregulation of endoplasmic reticulum (ER)-related pathways and proteins is one of the predominant hallmarks. We aimed to reveal the role of ring finger protein 5 (RNF5), an ER-localized E3 ubiquitin-protein ligase, in NASH and to explore its underlying mechanism. APPROACH AND RESULTS: We first inspected the expression level of RNF5 and found that it was markedly decreased in livers with NASH in multiple species including humans. We then introduced adenoviruses for Rnf5 overexpression or knockdown into primary mouse hepatocytes and found that palmitic acid/oleic acid (PAOA)-induced lipid accumulation and inflammation in hepatocytes were markedly attenuated by Rnf5 overexpression but exacerbated by Rnf5 gene silencing. Hepatocyte-specific Rnf5 knockout significantly exacerbated hepatic steatosis, inflammatory response, and fibrosis in mice challenged with diet-induced NASH. Mechanistically, we identified 3-hydroxy-3-methylglutaryl CoA reductase degradation protein 1 (HRD1) as a binding partner of RNF5 by systematic interactomics analysis. RNF5 directly bound to HRD1 and promoted its lysine 48 (K48)-linked and K33-linked ubiquitination and subsequent proteasomal degradation. Furthermore, Hrd1 overexpression significantly exacerbated PAOA-induced lipid accumulation and inflammation, and short hairpin RNA-mediated Hrd1 knockdown exerted the opposite effects. Notably, Hrd1 knockdown significantly diminished PAOA-induced lipid deposition, and up-regulation of related genes resulted from Rnf5 ablation in hepatocytes. CONCLUSIONS: These data indicate that RNF5 inhibits NASH progression by targeting HRD1 in the ubiquitin-mediated proteasomal pathway. Targeting the RNF5-HRD1 axis may provide insights into the pathogenesis of NASH and pave the way for developing strategies for NASH prevention and treatment.

8.
Food Chem ; 364: 130398, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34175630

RESUMO

Shiitake mushroom (Lentinus edodes) is the second most-widely-consumed edible fungi with strong flavor and unique taste. To study the effects of Lactiplantibacillus plantarum fermentation on umami compounds in shiitake mushrooms, the levels of taste-imparting compounds were analyzed, including organic acids, free amino acids, and 5'-nucleotides during fermentation. The contents of all umami compounds except for succinic acid and fumaric acid were improved with increasing fermentation time; broths obtained at each fermentation stage formed clear clusters upon subjecting the electronic tongue data to principal component and discriminant function analyses. Compounds that predominantly contributed to important umami were identified. Among the 30 umami compounds investigated, 11 compounds were considered to be predominantly responsible for the different taste characteristics of shiitake mushroom broths at various stages of fermentation. Taken together, L. plantarum fermentation improved the contents of umami taste compounds in shiitake mushroom.


Assuntos
Cogumelos Shiitake , Aminoácidos , Fermentação , Aromatizantes , Paladar
9.
Hepatology ; 74(4): 2133-2153, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34133792

RESUMO

BACKGROUND AND AIMS: Hepatic ischemia/reperfusion (I/R) injury, a common clinical problem that occurs during liver surgical procedures, causes a large proportion of early graft failure and organ rejection cases. The identification of key regulators of hepatic I/R injury may provide potential strategies to clinically improve the prognosis of liver surgery. Here, we aimed to identify the role of tumor necrosis factor alpha-induced protein 3-interacting protein 3 (TNIP3) in hepatic I/R injury and further reveal its immanent mechanisms. APPROACH AND RESULTS: In the present study, we found that hepatocyte TNIP3 was markedly up-regulated in livers of both persons and mice subjected to I/R surgery. Hepatocyte-specific Tnip3 overexpression effectively attenuated I/R-induced liver necrosis and inflammation, but improved cell proliferation in mice, whereas TNIP3 ablation largely aggravated liver injury. This inhibitory effect of TNIP3 on hepatic I/R injury was found to be dependent on significant activation of the Hippo-YAP signaling pathway. Mechanistically, TNIP3 was found to directly interact with large tumor suppressor 2 (LATS2) and promote neuronal precursor cell-expressed developmentally down-regulated 4-mediated LATS2 ubiquitination, leading to decreased Yes-associated protein (YAP) phosphorylation at serine 112 and the activated transcription of factors downstream of YAP. Notably, adeno-associated virus delivered TNIP3 expression in the liver substantially blocked I/R injury in mice. CONCLUSIONS: TNIP3 is a regulator of hepatic I/R injury that alleviates cell death and inflammation by assisting ubiquitination and degradation of LATS2 and the resultant YAP activation.TNIP3 represents a promising therapeutic target for hepatic I/R injury to improve the prognosis of liver surgery.

10.
J Agric Food Chem ; 69(20): 5638-5651, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33993695

RESUMO

Extensive studies focused on the therapeutic efficacy of epigallocatechin-3-gallate (EGCG) against bacterial infection. However, little is known about its prophylactic efficacy against bacterial infection. Herein, we found that EGCG showed an effective prophylactic efficacy against bacterial infection with a broad spectrum, including Gram-negative, Gram-positive, and drug-resistant bacteria. Pretreatment with EGCG through intraperitoneal injection, intravenous injection, or intragastric administration significantly reduced the bacterial load, inflammatory response, and mortality in mouse abdominal infection models induced by bacterial inoculation or cecal ligation and puncture. Pretreatment with EGCG by intraperitoneal injection significantly increased the numbers of neutrophils and monocytes/macrophages in the abdominal cavity and peripheral blood of mice, and depletion of neutrophils and monocytes/macrophages by specific antibodies or chemical drugs obviously increased the bacterial load in mice. Of note, EGCG did not directly induce neutrophil and macrophage migration, and it just induced phagocyte migration in the presence of macrophages in a co-cultured system, implying that EGCG-induced phagocyte migration relies on its immunoregulatory effects on macrophages. EGCG markedly induced the production of cytokines and chemokines in macrophages and mouse peritoneal lavage, including tumor necrosis factor-α (TNF-α), interleukin-1 ß (IL-1ß), IL-6, CXC chemokine ligands 1 and 2 (CXCL1 and 2), and monocyte chemotactic protein-1 (MCP-1). EGCG significantly induced the phosphorylation of p38 and JNK mitogen-activated protein kinases (MAPKs) in macrophages, and inhibition of p38 and JNK MAPKs markedly reduced EGCG-induced chemokine and cytokine production. Anti-67-kDa laminin receptor (67LR) antibody treatment significantly reduced EGCG-induced chemokine production and p38 and JNK phosphorylation in macrophages. Together, EGCG showed an obvious prophylactic efficacy against bacterial infection by inducing a pro-inflammatory response in macrophages through the 67LR/p38/JNK signaling pathway, supporting the further development of EGCG as a potent prophylaxis for bacterial infection and providing new clues to understand the healthcare function of green tea.


Assuntos
Infecções Bacterianas , Catequina , Preparações Farmacêuticas , Animais , Catequina/análogos & derivados , Sistema de Sinalização das MAP Quinases , Macrófagos/metabolismo , Camundongos , Receptores de Laminina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Small ; 17(10): e2007090, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33464716

RESUMO

Dual phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), has shown a great prospect in cancer treatment. However, its therapeutic effect is restricted by the depth of light penetration in tissue and tumor hypoxia environment. Herein, inspired by the specific response of nanozymes to the tumor microenvironment (TME), a simple and versatile nanozyme-mediated synergistic dual phototherapy nanoplatform (denoted as FePc/HNCSs) is constructed using hollow nitrogen-doped carbon nanospheres (HNCSs) and iron phthalocyanine (FePc). FePc/HNCSs simultaneously exhibit peroxidase (POD)- and catalase (CAT)-like activities, which not only can convert endogenous hydrogen peroxide (H2 O2 ) into highly toxic hydroxyl radicals (•OH) for catalytic therapy, but also decompose H2 O2 to oxygen (O2 ) to enhance O2 -dependent PDT. In addition, their enzyme-like activities are significantly enhanced under light irradiation. Combining with the excellent photothermal effect, FePc/HNCSs realize a high tumor inhibition rate of 96.3%. This strategy opens a new horizon for exploring a more powerful tumor treatment nanoplatform.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Neoplasias/tratamento farmacológico , Fototerapia , Hipóxia Tumoral , Microambiente Tumoral
12.
Chempluschem ; 86(1): 146-154, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33459522

RESUMO

The exploration and understanding of self-assembly and stimuli-responsive mechanisms of supramolecular systems are of fundamental importance for researchers to plan syntheses reasonably. Herein, the self-assembly and ions responsive mechanisms of a tripodal quinolinamido-based supramolecular organogel (TBT-gel) were investigated through experiments and theoretical calculations including independent gradient model (IGM), localized orbitals locator (LOL) and hole-electron theory. According to these studies, the self-assembly mechanism of TBT-gel was based on strong threefold H-bonding and π-π interactions, which induced the TBT forming helical, one-dimensional supramolecular polymer. After addition of Fe3+ into the TBT-gel, the one-dimensional supramolecular polymer had been crosslinked by the Fe3+ through coordination interaction and formed a metallogel (TBT-Fe-gel). Interestingly, the TBT-gel showed selective fluorescent response for Fe3+ and F- based on a competitive coordination mechanism. Moreover, the study on fluorescence responsive mechanism of TBT-gel for Fe3+ and F- implied the ICT mode governs both the electron excitation and de-excitation processes. The calculated results were in agreement with the corresponding experimental results. Notably, the quantum chemical calculations provided a deep understanding and visualized presentation of the assembly and stimuli-responsive mechanisms.

13.
Langmuir ; 36(45): 13469-13476, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33147040

RESUMO

The booming of host-guest assembly-based supramolecular chemistry provides abundant ways to construct functional systems and materials. Attracted by the important application prospect of white light emission and aggregation-induced emission (AIE) materials, herein, we report an efficient way for fabricating metal-free white light-emitting AIE materials through the supramolecular assembly of simple organic compounds: methoxyl pillar[5]arene (MP5) and tri-(pyridine-4-ylamido)benzene (TAP). By host-guest assembly, MP5 and TAP formed a supramolecular polymer (MP5-T); meanwhile, the MP5-T xerogel powder emitted white light at CIE coordinates (0.29 and 0.29). The supramolecular assembly and white light-emitting mechanisms were carefully investigated by experiments as well as quantum chemical calculations including density functional theory (DFT), reduced density gradient, electrostatic surface potential, independent gradient model, and frontier molecular orbital (highest-occupied molecular orbital-lowest-unoccupied molecular orbital) analyses. Interestingly, according to the experiments and calculations, the supramolecular assembly is critical in the white light-emitting phenomenon. Moreover, in this work, the quantum chemical calculations could not only support experimental phenomena but also provide deep understanding and visualized presentation of the assembly and emission mechanism. In addition, the obtained MP5-T solid powder could serve as a novel and easy means to make material for white light-emitting devices.

14.
Materials (Basel) ; 13(21)2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33105648

RESUMO

By combining density functional theory, quantum theory of atoms in molecules and transport properties calculations, we evaluated the thermoelectric properties of Sb-S system compounds and shed light on their relationships with electronic structures. The results show that, for Sb2S3, the large density of states (DOS) variation induces a large Seebeck coefficient. Taking into account the long-range weak bonds distribution, Sb2S3 should exhibit low lattice thermal conductivity. Therefore, Sb2S3 is promising for thermoelectric applications. The insertion of Be atoms into the Sb2S3 interstitial sites demonstrates the electrical properties and Seebeck coefficient anisotropy and sheds light on the understanding of the role of quasi-one-dimensional structure in the electron transport. The large interstitial sites existing in SbS2 are at the origin of phonons anharmonicity which counteracts the thermal transport. The introduction of Zn and Ga atoms into these interstitial sites could result in an enhancement of all the thermoelectric properties.

15.
Mol Med Rep ; 22(4): 3073-3080, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32945450

RESUMO

Diabetes mellitus poses a major threat towards global heath due to a lack of effective treatment. Fluoxetine hydrochloride, a selective 5­hydroxytryptamine reuptake inhibitor, is the most commonly used antidepressant in clinical therapy; however, the potential molecular mechanisms of fluoxetine in diabetes remain unknown. In the present study, reduced glucose, total cholesterol and triglyceride levels and lipid metabolism, as well as upregulated proliferator­activated receptor γ, fatty acid synthase and lipoprotein lipase, and downregulated sterol regulatory element­binding protein 1­c were detected in rats with streptozotocin (STZ)­induced diabetes following treatment with fluoxetine. Furthermore, fluoxetine significantly inhibited the expression levels of glucose metabolism­associated proteins in liver tissues, including glycogen synthase kinase 3ß (GSK­3ß), glucose­6 phosphatase catalytic subunit (G6PC), phosphoenolpyruvate carboxykinase (PEPCK) and forkhead box protein O1 (FOXO1). In addition, fluoxetine treatment notably attenuated morphological liver damage in rats with STZ­induced diabetes. Additionally, fluoxetine could inhibit the phosphatidylinositol 3­kinase­protein kinase B (PI3K­AKT) signaling pathway, whereas LY294002, a specific inhibitor of PI3K, suppressed the function of PI3K­AKT signaling and suppressed the expression levels of glucose metabolism­associated proteins, including GSK­3ß, G6PC, PEPCK and FOXO1 in BRL­3A cells. The results of the present study revealed that fluoxetine may regulate glucose and lipid metabolism via the PI3K­AKT signaling pathway in diabetic rats.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Fluoxetina/administração & dosagem , Metabolismo dos Lipídeos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular , Cromonas/farmacologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Estreptozocina
16.
PLoS One ; 15(8): e0236898, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785280

RESUMO

The development of fungal fruiting bodies from a hyphal thallus is inducible under low temperature (cold stress). The molecular mechanism has been subject to surprisingly few studies. Analysis of gene expression level has become an important means to study gene function and its regulation mechanism. But identification of reference genes (RGs) stability under cold stress have not been reported in famous medicinal mushroom-forming fungi Cordyceps militaris. Herein, 12 candidate RGs had been systematically validated under cold stress in C. militaris. Three different algorithms, geNorm, NormFinder and BestKeeper were applied to evaluate the expression stability of the RGs. Our results showed that UBC and UBQ were the most stable RGs for cold treatments in short and long periods, respectively. 2 RGs (UBC and PP2A) and 3 RGs (UBQ, TUB and CYP) were the suitable RGs for cold treatments in short and long periods, respectively. Moreover, target genes, two-component-system histidine kinase genes, were selected to validate the most and least stable RGs under cold treatment, which indicated that use of unstable expressed genes as RGs leads to biased results. Our results provide a good starting point for accurate reverse transcriptase quantitative polymerase chain reaction normalization by using UBC and UBQ in C. militaris under cold stress and better support for understanding the mechanism of response to cold stress and fruiting body formation in C. militaris and other mushroom-forming fungi in future research.


Assuntos
Resposta ao Choque Frio/genética , Cordyceps/genética , Cordyceps/fisiologia , Perfilação da Expressão Gênica/normas , Histidina Quinase/genética , Cordyceps/enzimologia , Padrões de Referência
17.
Photochem Photobiol Sci ; 19(10): 1373-1381, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32852021

RESUMO

A catechol-functionalized phenazine imidazole (PD) was tailored with 2,3-diaminophenazine and 3,4-dihydroxy benzaldehyde, and it served as a hybrid acceptor for capturing HSO4- anions. The selectivity and sensitivity of the PD receptor for anion sensing were studied. It was found that the PD receptor could not only display a preferable sensitivity to HSO4- ions with a "turn-off" fluorescence response, but also have a strong anti-interference ability toward other common anions, especially basic anions such as CH3COO-, HPO42-, and H2PO4-. The anion recognition mechanism of PD towards HSO4- is based on multiple hydrogen bond interactions. Finally, the strips for anion detection were prepared, which were verified to be a convenient and high-efficiency test kit for detecting HSO4- ions with the naked eye.


Assuntos
Fenazinas/química , Sulfitos/química , Ânions/química , Fluorescência , Estrutura Molecular , Tamanho da Partícula , Fenazinas/síntese química , Sulfitos/síntese química , Propriedades de Superfície
18.
Int J Med Mushrooms ; 22(2): 133-144, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32479002

RESUMO

Total phenolics, flavonoids, and polysaccharides, and individual ganoderic acid (GA) contents, antioxidant capacity, and transcription levels of key enzyme genes involved in GA biosynthesis in pileus and stipes of Ganoderma lucidum fruiting body at different growth stages were investigated in this study. Results showed that the highest total phenolics and total flavonoids contents were determined in stipes at spore maturity stage, resulting in high antioxidant activity, while the highest total polysaccharide content was found in pileus at the same stage. The pileus contained more GA than the stipes, and higher contents of ganoderic acid A and D were found at fruiting body mature stage while that of ganoderic acid B, C2, and G were found at bud elongation stage. Results from quantitative real-time PCR indicated that higher gene transcription levels of hydroxyl methylglutaryl-CoA reductase (hmgr), farnesyl pyrophosphate synthase (fps), squalene synthase (sqs), and oxidosqualene cyclase (osc) were found in pileus at bud elongation stage. Our findings will be helpful for understanding the biosynthesis of bioactive components and determining the harvest time for the desired G. lucidum fruiting bodies.


Assuntos
Antioxidantes/análise , Carpóforos/química , Proteínas Fúngicas/genética , Reishi/química , Triterpenos/metabolismo , Antioxidantes/metabolismo , Farnesil-Difosfato Farnesiltransferase/genética , Flavonoides/metabolismo , Carpóforos/enzimologia , Carpóforos/genética , Carpóforos/crescimento & desenvolvimento , Geraniltranstransferase/genética , Hidroxibenzoatos/metabolismo , Hidroximetilglutaril-CoA Redutases/genética , Transferases Intramoleculares/genética , Polissacarídeos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reishi/enzimologia , Reishi/genética , Reishi/crescimento & desenvolvimento , Triterpenos/análise
19.
Soft Matter ; 16(24): 5734-5739, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32525181

RESUMO

Stimuli-responsive optical materials attract lots of attention due to their broad applications. Herein, a novel smart stimuli-responsive supramolecular polymer was successfully constructed using a simple tripodal quaternary ammonium-based gelator (TH). The TH self-assembles into a supramolecular polymer hydrogel (TH-G) and shows aggregation-induced emission (AIE) properties. Interestingly, the transparency and fluorescence of the TH-G xerogel film (TH-GF) could be reversibly regulated by use of triethylamine (TEA) and hydrochloric acid (HCl) vapor. When alternately fumed with TEA and HCl vapor, the optical transmittance of the TH-GF was changed from 8.9% to 92.7%. Meanwhile, the fluorescence of the TH-G shows an "ON/OFF" switch. The reversible switching of the transparency and the fluorescence of the TH-GF is attributed to the assembly and disassembly of the supramolecular polymer TH-G. Based on these stimuli-response properties, the TH-GF could act as an optical material and shows potential applications as smart windows or fluorescent display material controlled by TEA and HCl vapor.

20.
J Infect ; 81(3): 420-426, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32504745

RESUMO

The seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was examined among 105 healthcare workers (HCWs) exposed to four patients who were laboratory confirmed with coronavirus disease 2019 (COVID-19), the disease caused by SARS-CoV-2 infection. These HCWs were immediately under quarantine for 14 days as soon as they were identified as close contacts. The nasopharyngeal swab samples were collected on the first and 14th day of the quarantine, while the serum samples were obtained on the 14th day of the quarantine. With the assay of enzyme immunoassay (EIA) and microneutralization assay, 17.14% (18/105) of HCWs were seropositive, while their swab samples were found to be SARS-CoV-2 RNA negative. Risk analysis revealed that wearing face mask could reduce the infection risk (odds ratio [OR], 0.127, 95% confidence interval [CI] 0.017, 0.968), while when exposed to COVID-19 patients, doctors might have higher risk of seroconversion (OR, 346.837, 95% CI 8.924, 13479.434), compared with HCWs exposed to colleagues as well as nurses and general service assistants who exposed to patients. Our study revealed that the serological testing is useful for the identification of asymptomatic or subclinical infection of SARS-CoV-2 among close contacts with COVID-19 patients.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Infecções por Coronavirus/sangue , Infecções por Coronavirus/imunologia , Pessoal de Saúde , Pneumonia Viral/sangue , Pneumonia Viral/imunologia , Adulto , COVID-19 , Busca de Comunicante , Infecções por Coronavirus/transmissão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Pandemias , Equipamento de Proteção Individual , Pneumonia Viral/transmissão , Fatores de Risco , SARS-CoV-2 , Estudos Soroepidemiológicos
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