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1.
Crit Rev Food Sci Nutr ; : 1-17, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37357923

RESUMO

Mycotoxins, secondary metabolites produced by mycotoxigenic fungi, are a major problem affecting food safety and security, because of their adverse health effects, their socio-economic impact and the difficulty of degradation or removal by conventional food processing methods. Plant-sourced natural products are a novel and effective control method for fungal infestation and mycotoxin production, with the advantages of biodegradability and acceptability for food use. However, development of resistance, low and inconsistent efficacy, and a limited range of antifungal activities hinder the effective application of single plant natural products for controlling mycotoxin contamination. To overcome these limitations, combinations of plant natural products have been tested extensively and found to increase efficacy, often synergistically. However, this extensive and promising research area has seen little development of practical applications. This review aims to provide up-to-date information on the antifungal, anti-mycotoxigenic and synergistic effects of combinations of plant natural products, as well as their mechanisms of action, to provide a reference source for future research and encourage application development.

2.
J Sci Food Agric ; 103(13): 6272-6279, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37163670

RESUMO

BACKGROUND: The widespread incidence of "false smut" disease in rice has caused extensive ustiloxin contamination around the world. Until now there has been a lack of knowledge regarding the natural occurrence of ustiloxins in paddy. The development of efficient removal methods is also still a challenge that remains unexplored. RESULTS: In the current study, three main ustiloxins - ustiloxin A (UA), ustiloxin B (UB), and ustiloxin G (UG) - were determined simultaneously by ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) in 206 paddy samples collected in 2021 from five rice-producing provinces in China. The predominant ustiloxin was UA with an occurrence of 46.1% and an average concentration of 49.71 µg kg-1 . This was followed by UB (31.1%, 13.31 µg kg-1 ) and UG (18.4%, 9.19 µg kg-1 ). No targeted ustiloxins were detected in white rice samples randomly collected from supermarkets in Shanghai. To reveal the causes, two approaches were tested for the removal of the ustiloxins: most of the targeted ustiloxins (>93%) were removed in brown rice by husking and, subsequently, all targeted ustiloxins (100%) were removed by whitening. CONCLUSION: A wide distribution of ustiloxins was discovered in paddy samples in this study. The UA contaminations were significantly different depending on their origin, with the highest occurrence in paddy from Shanghai and Jiangsu, southeast coast provinces in China. Contamination by UG was also found in paddy for the first time and was strongly correlated with those of UA and UB. A combination of husking and whitening has been verified to be a practicable and promising way to ensure efficient removal and food safety. © 2023 Society of Chemical Industry.


Assuntos
Micotoxinas , Oryza , Cromatografia Líquida , Oryza/química , Micotoxinas/análise , Espectrometria de Massas em Tandem , China
3.
Biophys J ; 121(21): 4109-4118, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36181266

RESUMO

The rhodopsin mimic is a chemically synthetized complex with retinyl Schiff base (RSB) formed between protein and the retinal chromophore that can mimic the natural rhodopsin-like protein. The artificial rhodopsin mimic is more stable and designable than the natural protein and hence has wider uses in photon detection devices. The mimic structure RSB, like the case in the actual rhodopsin-like protein, undergoes isomerization and protonation throughout the photoreaction process. As a result, understanding the dynamics of the RSB in the photoreaction process is critical. In this study, the ultrafast transient absorption spectra of three mutants of the cellular retinoic acid-binding protein II-based rhodopsin mimic at acidic environment were recorded, from which the related excited-state dynamics of the all-trans protonated RSB (AT-PRSB) were investigated. The transient fluorescence spectra measurements are used to validate some of the dynamic features. We find that the excited-state dynamics of AT-PRSB in three mutants share a similar pattern that differs significantly from the dynamics of 15-cis PRSB of the rhodopsin mimic in neutral solution. By comparing the dynamics across the three mutants, we discovered that the aromatic residues near the ß-ionone ring structure of the retinal may help stabilize the AT-PRSB and hence slow down its isomerization rate. The experimental results provide implications on designing a rhodopsin-like protein with significant infrared fluorescence, which can be particularly useful in the applications in biosensing or bioimaging in deeper tissues.


Assuntos
Rodopsina , Bases de Schiff , Rodopsina/química , Bases de Schiff/química , Isomerismo , Retina , Fótons , Retinaldeído/química
4.
Metab Brain Dis ; 37(7): 2163-2180, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35612695

RESUMO

Ischemic stroke (IS) is the most prevalent type of stroke. The early diagnosis and prognosis of IS are crucial for successful therapy and early intervention. Metabolomics, a tool in systems biology based on several innovative technologies, can be used to identify disease biomarkers and unveil underlying pathophysiological processes. Accordingly, in recent years, an increasing number of studies have identified metabolites from cerebral ischemia patients and animal models that could improve the diagnosis of IS and prediction of its outcome. In this paper, metabolomic research is comprehensively reviewed with a focus on describing the metabolic changes and related pathways associated with IS. Most clinical studies use biofluids (e.g., blood or plasma) because their collection is minimally invasive and they are ideal for analyzing changes in metabolites in patients of IS. We review the application of animal models in metabolomic analyses aimed at investigating potential mechanisms of IS and developing novel therapeutic approaches. In addition, this review presents the strengths and limitations of current metabolomic studies on IS, providing a reference for future related studies.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Biomarcadores , Metabolômica , Isquemia Encefálica/metabolismo , Acidente Vascular Cerebral/metabolismo
5.
Crit Rev Food Sci Nutr ; 60(9): 1523-1537, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30806521

RESUMO

Masked mycotoxins are biologically modified phase II metabolites formed by plant defense mechanisms through glucosylation catalyzed by uridine diphosphate -glucosyltransferases. Most of the current reports focus on the occurrence of masked mycotoxins in Europe, America, Africa, and cover other geographic regions, e.g. China and Japan. High proportions of masked mycotoxins co-occurring with their parent forms in various cereal-based food and feedstuff could clearly increase total exposures and pose additional health risks to humans and animals. In contrast to the parent mycotoxins, the data on the toxicity of masked mycotoxins are still scarce, however, the poor existing information showed that masked mycotoxins generally exhibit significant in vitro and in vivo toxicities lower than those of their parent forms, especially for deoxynivalenol-3-glucoside, which is the only thoroughly investigated masked mycotoxin. Although the lower toxicity level of masked mycotoxins, these are probably hydrolyzed into their free forms by intestinal microorganisms in the digestive tract of mammals and thus contribute to unpredicted toxicity. The metabolic characteristics of reported masked mycotoxins are species-specific. The most relevant animal model of human sensitivity, the pig, is most sensitive to masked mycotoxins. This review focuses on updates in the current knowledge on country-specific natural-occurrence data in global surveys, as well as in vitro and in vivo toxicology and metabolic investigations of masked mycotoxins.


Assuntos
Micotoxinas/metabolismo , Micotoxinas/toxicidade , Plantas/química , Animais , Contaminação de Alimentos/análise , Microbioma Gastrointestinal/fisiologia , Humanos , Micotoxinas/análise , Micotoxinas/química
6.
Int J Syst Evol Microbiol ; 70(1): 11-15, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31560297

RESUMO

Two novel strains (HT111-2T and HT170-2) of the genus Lactobacillus were isolated from Marmota himalayana faecal samples collected on the Qinghai-Tibet Plateau, PR China. The isolates were Gram-stain-positive, rod-shaped, non-spore-forming bacteria with irregular circular colonies. Phylogenetic analysis and comparison of the 16S rRNA gene sequences demonstrated that the two strains form a subcluster and are closest to Lactobacillus hamsteri JCM 6256T (97.3 %) and Lactobacillus amylolyticus DSM 11664T (97.2 %). Phylogenetic analysis of two housekeeping genes (rpoA and pheS) found that strains HT111-2T and HT170-2 had the same closest relatives as the 16S rRNA gene sequence analysis did. The G+C content of strains HT111-2T and HT170-2 were 38.8 mol%. The values of in silico DNA-DNA hybridization with known Lactobacillus species were lower than the threshold (70%). Average nucleotide identity values of strain HT111-2T with L. hamsteri JCM 6256T and L. amylolyticus DSM 11664T were 77.84 % and 76.85 %, respectively. The major fatty acids of strains HT111-2T and HT170-2 were C16 : 0, C18 : 1ω9c and C18 : 0. Results of phenotypic, chemotaxonomic and phylogenetic analyses suggest strains HT111-2T and HT170-2 represent a novel species of the genus Lactobacillus, for which the name Lactobacillus xujianguonis sp. nov. is proposed with HT111-2T (=CGMCC 1.13855T=KCTC 15803T) as the type strain.


Assuntos
Lactobacillus/classificação , Marmota/microbiologia , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Genes Bacterianos , Lactobacillus/isolamento & purificação , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet
7.
Anal Chem ; 91(6): 4116-4123, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30793880

RESUMO

An innovative approach based on a surface functional monomer-directing strategy for the construction of a sensitive and selective molecularly imprinted electrochemical sensor for patulin recognition is described. A patulin imprinted platinum nanoparticle (PtNP)-coated poly(thionine) film was grown on a preformed thionine tailed surface of PtNP-nitrogen-doped graphene (NGE) by electropolymerization, which provided high capacity and fast kinetics to uptake patulin molecules. Thionine acted not only as a functional monomer for molecularly imprinted polymer (MIP), but also as a signal indicator. Enhanced sensitivity was obtained by combining the excellent electric conductivity of PtNPs, NGE, and thionine with multisignal amplification. The designed sensor displayed excellent performance for patulin detection over the range of 0.002-2 ng mL-1 (R2 = 0.995) with a detection limit of 0.001 ng mL-1 for patulin. In addition, the resulting sensor showed good stability and high repeatability and selectivity. Furthermore, the feasibility of its applications has also been demonstrated in the analysis of real samples, providing novel tactics for the rational design of MIP-based electrochemical sensors to detect a growing number of deleterious substances.


Assuntos
Cromatografia de Afinidade/métodos , Técnicas Eletroquímicas/métodos , Sucos de Frutas e Vegetais/análise , Impressão Molecular/métodos , Mutagênicos/análise , Patulina/análise , Fenotiazinas/química , Técnicas Biossensoriais , Limite de Detecção , Malus/química , Mutagênicos/química , Nanopartículas/química , Patulina/química , Patulina/isolamento & purificação , Vitis/química
8.
Int J Syst Evol Microbiol ; 69(11): 3629-3635, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31511125

RESUMO

Two Gram-stain-positive, irregular rod-shaped (0.2-0.5×1.3-2.5 um) strains, HY056T and HY057, were isolated from the faeces of Equus kiang (the largest of the wild asses) collected at different regions from the Qinghai-Tibetan Plateau of PR China. Phylogenetic analyses indicated that strains HY056T and HY057 belong to the genus Nocardioides by sharing a similarity ranging from 96.3 to 97.0 % in the 16S rRNA gene sequence and forming a distinct cluster with Nocardioides daphniae JCM 16608T, Nocardioides houyundeii 78T, Nocardioides solisilvae Ka25T and Nocardioides gilvus XZ17T. The digital DNA-DNA hybridization value of strain HY056T was 96.9 % with strain HY057, but less than 30.0 % with the above four closest relatives. MK-8(H4) was the predominant (91.6 %) respiratory quinone. The cell wall contained ll-2,6-diaminopimelic acid as the diamino acid of the peptidoglycan. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and phospholipid. The predominant fatty acids (>10.0 %) were C18 : 1ω9c and iso-C16:0. The DNA G+C contents of strains HY056T and HY057 were 68.9 and 69.1 mol%, respectively. ß-Glucosidase expression was positive, and acid was produced from d-fructose. Strain HY056T (=CGMCC 4.7563T=JCM 33399T) is assigned as the type strain of a novel species within the genus Nocardioides, for which the name Nocardioidesyefusunii sp. nov is proposed.


Assuntos
Actinobacteria/classificação , Equidae/microbiologia , Fezes/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/análogos & derivados , Vitamina K 2/química
9.
Molecules ; 21(6)2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27258245

RESUMO

Sorbicillinoids are important hexaketide metabolites derived from fungi. They have a variety of biological activities including cytotoxic, antioxidant, antiviral and antimicrobial activity. The unique structural features of the sorbicillinoids make them attractive candidates for developing new pharmaceutical and agrochemical agents. About 90 sorbicillinoids have been reported in the past few decades. This mini-review aims to briefly summarize their occurrence, structures, and biological activities.


Assuntos
Produtos Biológicos/química , Produtos Biológicos/farmacologia , Cicloexanonas/química , Cicloexanonas/farmacologia , Fungos/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Produtos Biológicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Cicloexanonas/isolamento & purificação , Humanos , Estrutura Molecular
10.
Molecules ; 19(6): 7169-88, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24886942

RESUMO

Bis-naphtho-γ-pyrones are an important group of aromatic polyketides derived from fungi. They have a variety of biological activities including cytotoxic, antitumor, antimicrobial, tyrosine kinase and HIV-1 integrase inhibition properties, demonstrating their potential applications in medicine and agriculture. At least 59 bis-naphtho-γ-pyrones from fungi have been reported in the past few decades. This mini-review aims to briefly summarize their occurrence, biosynthesis, and structure, as well as their biological activities. Some considerations regarding to synthesis, production, and medicinal and agricultural applications of bis-naphtho-γ-pyrones are also discussed.


Assuntos
Fungos/química , Pironas/metabolismo , Pironas/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Apoptose/efeitos dos fármacos , Humanos , Inibidores de Integrase/química , Inibidores de Integrase/metabolismo , Inibidores de Integrase/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Policetídeos/química , Policetídeos/metabolismo , Policetídeos/farmacologia , Pironas/química
11.
Molecules ; 19(9): 14221-34, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25211003

RESUMO

Hyalodendriella sp. Ponipodef12, an endophytic fungus from the hybrid "Neva" of Populus deltoides × P. nigra, is a high producer of the bioactive dibenzo-α-pyrones botrallin and TMC-264. However, both the botrallin and TMC-264 produced by Hyalodendriella sp. Ponipodef12 were retained as both intracellular and extracellular products. The aim of this study was to evaluate an in situ macroporous resin adsorption for enhancement of botrallin and TMC-264 production in mycelial liquid culture of Hyalodendriella sp. Ponipodef12. Production of botrallin and TMC-264 was most effectively enhanced by macroporous resin DM-301 among the thirteen nonionic macroporous resins tested. The highest botrallin yield (51.47 mg/L, which was 2.29-fold higher than the control at 22.49 mg/L) was obtained by adding resin DM-301 at 4.38% (g/mL) to the culture broth on day 24 and allowing a period of 4 days for adsorption. The highest TMC-264 yield reached 47.74 mg/L, which was 11.76-fold higher than that of the control (4.06 mg/L), and was achieved by adding DM-301 resin at 4.38% (w/v) in the culture broth on day 24 and allowing a period of 6 days for adsorption. The results show that in situ resin adsorption is an effective strategy for enhancing production of botrallin and TMC-264, and also for facilitating their recovery from mycelial liquid culture of Hyalodendriella sp. Ponipodef12.


Assuntos
Compostos Heterocíclicos com 3 Anéis/isolamento & purificação , Pironas/isolamento & purificação , Adsorção , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Reatores Biológicos , Técnicas de Cultura , Compostos Heterocíclicos com 3 Anéis/metabolismo , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Porosidade , Pironas/metabolismo , Resinas Sintéticas/química
12.
J Phys Chem B ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940335

RESUMO

Microbial rhodopsin, a pivotal photoreceptor protein, has garnered widespread application in diverse fields such as optogenetics, biotechnology, biodevices, etc. However, current microbial rhodopsins are all transmembrane proteins, which both complicates the investigation on the photoreaction mechanism and limits their further applications. Therefore, a specific mimic for microbial rhodopsin can not only provide a better model for understanding the mechanism but also can extend the applications. The human protein CRABPII turns out to be a good template for design mimics on rhodopsin due to the convenience in synthesis and the stability after mutations. Recently, Geiger et al. designed a new CRABPII-based mimic M1-L121E on microbial rhodopsin with the 13-cis, syn (13C) isomerization after irradiation. However, it still remains a question as to how similar it is compared with the natural microbial rhodopsin, in particular, in the aspect of the photoreaction dynamics. In this article, we investigate the excited-state dynamics of this mimic by measuring its transient absorption spectra. Our results reveal that there are two components in the solution of mimic M1-L121E at pH 8, known as protonated Schiff base (PSB) and unprotonated Schiff base (USB) states. In both states, the photoreaction process from 13-cis, syn(13C) to all-trans,anti (AT) is faster than that from the inverse direction. In addition, the photoreaction process in the PSB state is faster than that in the USB state. We compared the isomerization time of the PSB state to that of microbial rhodopsin. Our findings indicate that M1-L121E exhibits behaviors similar to those of microbial rhodopsins in the general pattern of PSB isomerization, where the isomerization from 13C to AT is much faster than its inverse direction. However, our results also reveal significant differences in the excited-state dynamics of the mimic relative to the native microbial rhodopsin, including the slower PSB isomerization rates as well as the unusual USB photoreaction dynamics at pH = 8. By elucidating the distinctive characteristics of mimics M1-L121E, this study enhances our understanding of microbial rhodopsin mimics and their potential applications.

13.
J Biomed Mater Res A ; 112(7): 1004-1014, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38327244

RESUMO

After implantation of the Mg alloy in the human body, the adsorption of plasma protein on surface will cause a series of cell reactions and affect the degradation of Mg alloys. Herein, in vitro biological reactions of the ZK60 and AZ31 Mg alloys are analyzed in plasma protein environment. Combined with mass spectrometry analysis of the type of adsorbed proteins, it is shown that proteins such as fibrinogen, vitronectin, fibronectin, and prothrombin are prone to get adsorbed on the surface of the alloys than other proteins, leading to the promotion of MG63 cell adhesion and proliferation. The effect of selected proteins (fibrinogen, fibronectin, and prothrombin) on degradation of ZK60 and AZ31 Mg alloys is investigated using immersion tests. The degradation of AZ31 Mg alloy is significantly restrained with the presence of proteins. This is due to the protein adsorption effect on the sample surface. The molecular dynamics simulation results indicate that both fibrinogen and fibronectin tend to adsorb onto the AZ31 rather than ZK60, forming a stable protein layer on the AZ31 Mg alloy retarding the degradation of the samples. As to ZK60 alloy, the addition of protein inhibits the degradation in the short term, however, the degradation increases after a long time of immersion. This phenomenon is particularly pronounced in fibronectin solution.


Assuntos
Ligas , Materiais Biocompatíveis , Proteínas Sanguíneas , Magnésio , Teste de Materiais , Ligas/química , Ligas/farmacologia , Humanos , Materiais Biocompatíveis/química , Magnésio/química , Magnésio/farmacologia , Proteínas Sanguíneas/química , Proteínas Sanguíneas/metabolismo , Adsorção , Fibronectinas/química , Proliferação de Células/efeitos dos fármacos , Simulação de Dinâmica Molecular , Adesão Celular/efeitos dos fármacos , Fibrinogênio/química
14.
Molecules ; 18(12): 15587-99, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24352015

RESUMO

Two spirobisnaphthalenes, namely palmarumycins C2 and C3, were isolated from cultures of the endophytic fungus Berkleasmium sp. Dzf12 after treatment with 1-hexadecene. After addition of 1-hexadecene at 10% to the medium on day 6 of culture, the maximal yields of palmarumycins C2 and C3 were obtained as 0.40 g/L and 1.19 g/L, which were 40.00 fold and 59.50 fold higher, respectively, in comparison with those of the control (0.01 g/L and 0.02 g/L). The results indicated that addition of 1-hexadecene can be an effective strategy for enhancing the production of palmarumycins C2 and C3 in liquid culture of endophytic fungus Berkleasmium sp. Dzf12. Palmarumycin C3 exhibited stronger antimicrobial and antioxidant activities than palmarumycin C2.


Assuntos
Ascomicetos/efeitos dos fármacos , Endófitos/efeitos dos fármacos , Álcoois Graxos/química , Naftalenos/química , Naftalenos/farmacologia , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Ascomicetos/metabolismo , Cromatografia Líquida de Alta Pressão , Endófitos/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Naftalenos/metabolismo , Compostos de Espiro/metabolismo
15.
Sci Total Environ ; 864: 161058, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36565876

RESUMO

Deoxynivalenol (DON) can easily injure the intestinal tract, which represents the first barrier against food contaminants. The intestinal toxicity induced by DON was mainly focused on mitogen-activated protein kinase (MAPK) activation, however, the underlying mechanisms by which DON triggers apoptosis by other pathways remain poorly understood. In this study, the Janus kinase 2/signal transducers and activators of transcription 3 (JAK2/STAT-3) pathway was proposed to regulate the intrinsic apoptosis induced by DON and thoroughly investigated in intestinal porcine epithelial cells (IPEC-J2). First, DON was found to be able to efficiently inhibit cell viability and increase the release of lactate dehydrogenase. It could also enhance the activity of the cleaved caspase-3 in a time-dependent manner, accompanied by a loss of mitochondrial membrane potential and an up-regulation of the apoptosis rate. Then, the expression of genes associated with inflammation and apoptosis were investigated. DON increased the expression of IL-6, IL-1ß, TNF-α, SOCS3 and Bax, but decreased the expression of Bcl-2 and Bcl-xL. Moreover, we discovered that DON robustly inhibited STAT-3 activity together with the down-regulation of JAK2, Bcl-2 and Bcl-xL, paralleling the increase in p38 phosphorylation. Furthermore, a pharmacological activation of JAK2/STAT-3 alleviated DON induced-apoptosis. Concurrent with the apoptotic pathway, during the initial exposure to DON (first 4 h), a survival pathway involving phosphorylated Erk1/2, Akt, and FoxO1 was also observed. Thus, apoptosis induced by DON was Janus faced: although the survival pathway was activated, the DON-induced apoptotic JAK2/STAT-3/caspase-3 pathway dominated, leading to an imbalance in cell homeostasis. This study provides a novel avenue to comprehensively reveal the pathological mechanisms of DON-induced intestinal disorders, which is promising for future applications to other contaminants in food and feed.


Assuntos
Apoptose , Janus Quinase 2 , Animais , Suínos , Janus Quinase 2/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Células Epiteliais , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
16.
J Agric Food Chem ; 71(46): 17723-17732, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37938806

RESUMO

Ustilaginoidea virens is a destructive phytopathogenic fungus that causes false smut disease in rice. In this study, the natural product 2,4-di-tert-butylphenol (2,4-DTBP) was found to be an environmentally friendly and effective agent for the first time, which exhibited strong antifungal activity against U. virens, with an EC50 value of 0.087 mmol/L. The scanning electron microscopy, fluorescence staining, and biochemical assays indicated that 2,4-DTBP could destroy the cell wall, cell membrane, and cellular redox homeostasis of U. virens, ultimately resulting in fungal cell death. Through the transcriptomic analysis, a total of 353 genes were significantly upregulated and 367 genes were significantly downregulated, focusing on the spindle microtubule assembly, cell wall and membrane, redox homeostasis, mycotoxin biosynthesis, and intracellular metabolism. These results enhanced the understanding of the antifungal activity and action mechanisms of 2,4-DTBP against U. virens, supporting it to be a potential antifungal agent for the control of false smut disease.


Assuntos
Hypocreales , Oryza , Antifúngicos/farmacologia , Hypocreales/genética , Fenóis/farmacologia , Oryza/genética , Doenças das Plantas/microbiologia
17.
Front Psychol ; 14: 1268091, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38145000

RESUMO

This study examines the impact of ethical leadership on top management team (TMT) decision-making regarding corporate social responsibility (CSR), considering the mediating role of TMT passion and the moderating role of performance stress. The study distinguishes between TMT harmonious and obsessive work passion and categorizes CSR as proactive and reactive. The findings reveal the following: (1) Ethical leadership positively influences proactive CSR, with TMT harmonious work passion acting as a positive mediator and TMT obsessive work passion playing a negative mediating role; (2) ethical leadership positively affects reactive CSR, with both TMT harmonious and obsessive work passion serving as positive mediators; (3) performance stress diminishes the impact of ethical leadership on TMT harmonious work passion; however, it amplifies the effect on TMT obsessive work passion. Consequently, the mediating effect of TMT harmonious work passion weakens, while the mediating effect of TMT obsessive work passion strengthens. This study emphasizes the significant role of TMT in CSR strategic decision-making and proposes a novel mediating mechanism through which ethical leadership drives CSR decision-making by considering TMT work passion. These findings reconcile the theoretical-practical conflict and have important theoretical and practical implications for enterprises in fulfilling their social responsibility.

18.
Front Plant Sci ; 14: 1202738, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37560029

RESUMO

A systematic study was carried out on 638 wheat and paddy grains (including fresh and stored samples) collected in 2021 from Shanghai, China, to identify the major mycobiota and their toxigenic abilities. A total of 349 fungi, namely, 252 Fusarium, 53 Aspergillus, and 44 Alternaria, were characterized by morphological and molecular identification. Fusarium and Aspergillus were more frequently isolated in paddy with Fusarium sambucinum species complex and Aspergillus section flavi as the predominant species, respectively. The genus Alternaria was the most frequently isolated fungal species in wheat. The toxin-producing potentials of the identified fungi were further evaluated in vitro. Deoxynevalenol (DON) was produced by 34.5% of Fusarium isolates and zearalenone (ZEN) was produced by 47.6% of them, and one isolate also processed the abilities for fumonisin B1 (FB1), B2 (FB2), and B3 (FB3) productions. Aflatoxin B1 (AFB1), B2 (AFB2), and G1 (AFG1) were only generated by Aspergillus section flavi, with the production rate of 65.5%, 27.6%, and 13.8%, respectively. Alternariol (AOH) was the most prevalent Alternaria toxin, which could be produced by 95.5% of the isolates, followed by alternariol monomethyl ether (AME) (72.7%), altenuene (ALT) (52.3%), tenuazonic acid (TeA) (45.5%), tentoxin (TEN) (29.5%), and altenusin (ALS) (4.5%). A combinational analysis of mycobiota and toxigenic ability allowed us to provide comprehensive information about the production mechanisms of mycotoxins in wheat and paddy in a specific geographic area, and will be helpful for developing efficient prevention and control programs.

19.
J Mater Chem B ; 10(42): 8596-8615, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36264053

RESUMO

Rare earth-doped nanocrystals are widely used in medical diagnostics and bioimaging due to their narrow luminescence emission spectra (10-20 nm), long lifetime, and no photobleaching properties. Especially in the near-infrared (NIR) region, deeper tissue imaging can be achieved with low background luminescence and high spatial resolution. Further precise image-guided diagnosis and treatment can be achieved by using multimodal imaging such as MRI/CT/NIR/PA. Here, we focus on the construction of rare earth-doped nanocrystals, optical properties, and progress of such nanocomposites for bioimaging in the NIR region. In addition, the limitations at this stage in the field of bioimaging and the prospects for future technological development of rare earth-doped nanocrystals are present.


Assuntos
Metais Terras Raras , Nanopartículas , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Metais Terras Raras/química , Luminescência , Nanopartículas/química , Imageamento por Ressonância Magnética
20.
Materials (Basel) ; 15(22)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36431560

RESUMO

The development of polymer-based composites with a high thermal conductivity and electromagnetic interference (EMI) shielding performance is crucial to the application of polymer-based composites in electronic equipment. Herein, a novel strategy combining ice-templated assembly and stress-induced orientation was proposed to prepare polydimethylsiloxane (PDMS)/alumina/carbon fiber (CF) composites. CF in the composites exhibited a highly oriented structure in the horizontal direction. Alumina was connected to the CF, promoting the formation of thermal conductive pathways in both the horizontal and vertical directions. As the CF content was 27.5 vol% and the alumina content was 14.0 vol%, the PDMS/alumina/CF composite had high thermal conductivities in the horizontal and vertical directions, which were 8.44 and 2.34 W/(m·K), respectively. The thermal conductivity in the horizontal direction was 40.2 times higher than that of PDMS and 5.0 times higher than that of the composite with a randomly distributed filler. The significant enhancement of the thermal conductivity was attributed to the oriented structure of the CF and the bridging effect of alumina. The PDMS/alumina/CF composite exhibited an excellent EMI shielding effectiveness of 40.8 dB which was 2.4 times higher than that of the composite with a randomly distributed filler. The PDMS/alumina/CF composite also exhibited a low reflectivity of the electromagnetic waves. This work could provide a guide for the research of polymer-based composites with a high thermal conductivity and an EMI shielding performance.

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