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1.
J Environ Manage ; 354: 120327, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38359627

RESUMO

Sweet sorghum, as a seasonal energy crop, is rich in cellulose and hemicellulose that can be converted into biofuels. This work aims at investigating the effects of synergistic regulation of Pichia anomala and cellulase on ensiling quality and microbial community of sweet sorghum silages as a storage and pretreatment method. Furthermore, the combined pretreatment effects of ensiling and ball milling on sweet sorghum were evaluated by microstructure change and enzymatic hydrolysis. Based on membership function analysis, the combination of P. anomala and cellulase (PA + CE) significantly improved the silage quality by preserving organic components and promoting fermentation characteristics. The bioaugmented ensiling with PA + CE restructured the bacterial community by facilitating Lactobacillus and inhibiting undesired microorganisms by killer activity of P. anomala. The combined bioaugmented ensiling pretreatment with ball milling significantly increased the enzymatic hydrolysis efficiency (EHE) to 71%, accompanied by the increased specific surface area and decreased pore size/crystallinity of sweet sorghum. Moreover, the EHE after combined pretreatment was increased by 1.37 times compared with raw material. Hence, the combined pretreatment was demonstrated as a novel strategy to effectively enhance enzymatic hydrolysis of sweet sorghum.


Assuntos
Celulase , Saccharomycetales , Sorghum , Hidrólise , Sorghum/química , Sorghum/metabolismo , Silagem/análise , Silagem/microbiologia , Celulase/metabolismo , Fermentação
2.
Toxicon ; 235: 107313, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37832850

RESUMO

Microcystins constitute a class of toxins synthesized by cyanobacteria and are known to inflict significant damage on the antioxidant defense system of living organisms, primarily targeting the liver. α-Lipoic acid (α-LA) is universally recognized as a potent antioxidant in biological systems. It exerts its beneficial effects through multiple mechanisms-directly neutralizing reactive oxygen species (ROS) and free radicals, and indirectly enhancing antioxidant defenses by facilitating the regeneration of glutathione (GSH). However, the precise modus operandi of α-LA's protective effect against Microcystin-LR-induced hepatotoxicity remains incompletely elucidated. The present study, therefore, employed α-LA to explore its protective role against Microcystin-LR exposure in mice. A model of Microcystin-LR-induced hepatic injury was established by administering Microcystin-LR into the peritoneal cavity of BALB/c mice daily over a two-week period. Thereafter, BALB/c mice were pre-treated with varying concentrations of α-LA via oral gavage for a duration of 7 days, followed by a 7-day exposure to Microcystin-LR. Our findings reveal that α-LA pre-treatment significantly mitigated hepatic pathologies in Microcystin-LR-exposed mice. Furthermore, α-LA administration led to a notable elevation in the activities and expression levels of nuclear factor erythroid 2-related factor 2, superoxide dismutase, glutathione peroxidase, glutathione S-transferase, and glutathione-indicative of its antioxidative capacity. Concurrently, a significant decrease was observed in the activities and expression levels of malondialdehyde and cytochrome P450 2E1. Consequently, α-LA emerges as a promising therapeutic candidate for the amelioration of liver oxidative damage subsequent to Microcystin-LR exposure.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Animais , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Microcistinas/toxicidade , Microcistinas/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Glutationa/metabolismo
3.
Front Public Health ; 10: 944942, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36117609

RESUMO

The COVID-19 pandemic has caused millions of deaths, seriously hampering people's lives and their productivity. Drawing on social information processing theory, this research developed a moderated mediation model to investigate the influence of perceived COVID-19 crisis strength on individuals' well-being. The results from a sample of 441 suggest that individuals' perceived COVID-19 crisis strength indirectly affects their life satisfaction and sleep quality via their perceived risk of being infected. Moreover, both individuals' trust in local government and mindfulness trait can buffer the positive effect of perceived COVID-19 crisis strength on their perceived risk of being infected. At the same time, they also buffer the indirect impact of individuals' perceived COVID-19 crisis strength on life satisfaction and sleep quality through perceived risk of being infected. This research provides several practical implications for governments and individuals to mitigate the negative influences of the COVID-19 pandemic and help individuals boost life satisfaction and sleep quality.


Assuntos
COVID-19 , Humanos , Pandemias , Satisfação Pessoal , Qualidade do Sono
4.
Front Psychol ; 13: 938864, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36118445

RESUMO

The COVID-19 pandemic has created enormous challenges for organizations and employees. Due to the effectiveness of idiosyncratic deals (i-deals for short) in management practices, more and more organizations use this human resource management tool to address the challenges posed by the COVID-19 pandemic. However, whether there are potential risks or negative effects of i-deals in the COVID-19 pandemic environment is not very clear. Drawing upon social cognitive theory, we proposed that i-deals may foment focal employees' unethical behavior by triggering their hubristic pride, and such process may be moderated by their trait of grandiose narcissism. We conducted a survey during the COVID-19 outbreak and tested our hypotheses with 492 samples from Shandong Province, China. Consistent with predictions, we found a positive relationship between i-deals and hubristic pride, which, in turn, increased their unethical behavior. And the relationship between i-deals and unethical behavior was mediated by hubristic pride. Furthermore, grandiose narcissism strengthened the positive relationship between i-deals and hubristic pride, as well as the indirect effect of i-deals on unethical behavior via hubristic pride. Our findings contributed to the literature on i-deals and provided guidance for organizations to address the challenges posed by the COVID-19 pandemic.

5.
Artigo em Inglês | MEDLINE | ID: mdl-35270716

RESUMO

Environmental problems caused by excessive carbon emissions are becoming increasingly prominent and have received heightened attention in recent years. Encouraging people to adopt low-carbon behavior to reduce carbon emissions is desirable. Based on social learning theory, we developed and tested a moderated mediation model to investigate when and how environmentally specific servant (ESS) leadership impacts employees' low-carbon behavior (i.e., private low-carbon behavior and public low-carbon behavior). We tested our theoretical framework with a sample of 483 subordinates and their direct supervisors working in northern China. The results indicate that ESS leadership is positively related to employees' low-carbon behavior, and that environmental self-accountability plays a mediating role in this relationship. In addition, power distance orientation strengthens the direct effects of ESS leadership on employees' environmental self-accountability and low-carbon behavior, as well as the indirect effect of ESS leadership on private low-carbon behavior via environmental self-accountability. Our findings contribute to the literature surrounding ESS leadership and low-carbon behavior, and help to promote green development and thus achieve the goals of carbon neutrality and decreasing carbon dioxide emissions.


Assuntos
Liderança , Responsabilidade Social , China , Humanos , Negociação
6.
Front Psychol ; 12: 696309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421746

RESUMO

Applied social cognitive theory, this study built a moderated mediation model to explain how and when development idiosyncratic deals (i-deals) affect recipients' turnover intention. Specifically, this study proposed two paths that linked development i-deals with the recipients' turnover intention. One path was a retention path via perceived internal employability and another path was a turnover path via perceived external employability. This study tested the hypotheses with a sample of 337 employees from three companies in China. The results showed that development i-deals improved recipients' perception of internal and external employability both. Perceived internal employability predicted low risk of turnover, but perceived external employability predicted high risk of turnover. And perceived internal and external employability played mediating roles in the relationship between development i-deals and turnover intention. Furthermore, the recipients' perception of opportunity to perform in current organization strengthened the relationship between perceived internal employability and turnover intention, but weakened the relationship between perceived external employability and turnover intention. Theoretical and practical implications of these findings were discussed.

7.
J Ethnopharmacol ; 260: 113062, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32512042

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Polygala fallax Hemsl. is a kind of traditional medicine of Yao Minority in China. In Chinese medicine practice, Polygala fallax Hemsl. is commonly prescribed to treat all kinds of acute and chronic hepatitis. AIM OF THE STUDY: The present study aimed at investigating the effects and its possible mechanism of Polygala fallax Hemsl. on the proliferation and apoptosis of HepG2 cells (a kind of human hepatoma cell). MATERIALS AND METHODS: Through a variety of experimental methods, including MTT technique and Hoechst staining to detect apoptosis in Hepatocyte HepG2 cells, flow cytometry to observe the pro-apoptotic and circulatory arrest effects as well as real-time fluorescence quantitative polymerase chain reaction (q-PCR) technique to examine the expression levels of Bcl-2/Bax gene and prote Western blot to examine the expression levels of bcl-2/bax,caspase3,8,9,CyclinA,p21,p27,ERK.Phospho-ERK and AKT, Phospho-AKT in HepG2 cells. RESULTS: The results showed that compared with the control group, all polarity fractions of P. fallax had inhibitory effects on HepG2 cells, among which the inhibition effect of ethyl acetate fraction in 0.036 ± 0.001 mg/mL of IC50 for 24 h was the most obvious (P < 0.01). And the HepG2 cells induced at the ethyl acetate fraction could up-regulate Bax gene and protein, while down-regulating Bcl-2 gene and protein (P < 0.05) during S phase in a dose-dependent manner. In addition, the ethyl acetate site of Larch can also down regulate the expression of ERK, AKT and activate caspase 3, 8 and 9. CONCLUSION: It could be concluded that the ethyl acetate fraction of Polygala fallax Hemsl. can significantly prohibit the proliferation of HepG2 cells. The possible mechanism is to promote the expression of Bax, inhibit the expression of Bcl-2, and down regulate the expression of AKT and ERK.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Extratos Vegetais/farmacologia , Polygala , Acetatos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Concentração Inibidora 50 , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Extratos Vegetais/isolamento & purificação , Polygala/química , Transdução de Sinais , Solventes/química
8.
Stem Cells ; 38(3): 340-351, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31778238

RESUMO

Embryonic stem cells (ESCs) have self-renewal and multi-lineage differentiation potential and perform critical functions in development and biomedicine. Several long noncoding RNAs (lncRNAs) have been reported as key regulators of stem cell pluripotency and differentiation. However, the function and regulatory mechanism of lncRNAs during the initiation of ESC differentiation remains unclear. Here, we found that linc1557 was highly expressed in mouse ESCs and required for the initiation of ESC differentiation. Knockdown of linc1557 increased the expression and phosphorylation levels of signal transducer and activator of transcription 3 (STAT3), a key factor in the leukemia inhibitory factor (LIF)/STAT3 signaling pathway. Furthermore, we found that linc1557 directly bound to Stat3 mRNA and affected its stability. The differentially expressed transcriptome after linc1557 knockdown in ESCs was involved primarily in multicellular organism development and cell differentiation as similar to that after Stat3 knockdown. Moreover, either knockdown of Stat3 or addition of a LIF/STAT3 signaling inhibitor rescued the suppressive effects of linc1557 knockdown on the initiation of mouse ESC differentiation. These findings not only elucidated the critical function of linc1557 in the initiation of mouse ESC differentiation but also clarified that its specific mechanism as directly affecting Stat3 mRNA stability, which enhanced the understanding of the lncRNA-mediated regulatory mechanism for mRNA stability and key signaling pathways in ESC pluripotency and differentiation.


Assuntos
Fator Inibidor de Leucemia/metabolismo , Células-Tronco Embrionárias Murinas/metabolismo , Animais , Diferenciação Celular , Camundongos , Fator de Transcrição STAT3 , Transdução de Sinais
9.
Nucleic Acids Res ; 46(8): 3906-3920, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29529255

RESUMO

Previous studies have revealed the critical roles of N6-methyladenosine (m6A) modification of mRNA in embryonic stem cells (ESCs), but the biological function of m6A in large intergenic noncoding RNA (lincRNA) is unknown. Here, we showed that the internal m6A modification of linc1281 mediates a competing endogenous RNA (ceRNA) model to regulate mouse ESC (mESC) differentiation. We demonstrated that loss of linc1281 compromises mESC differentiation and that m6A is highly enriched within linc1281 transcripts. Linc1281 with RRACU m6A sequence motifs, but not an m6A-deficient mutant, restored the phenotype in linc1281-depleted mESCs. Mechanistic analyses revealed that linc1281 ensures mESC identity by sequestering pluripotency-related let-7 family microRNAs (miRNAs), and this RNA-RNA interaction is m6A dependent. Collectively, these findings elucidated the functional roles of linc1281 and its m6A modification in mESCs and identified a novel RNA regulatory mechanism, providing a basis for further exploration of broad RNA epigenetic regulatory patterns.


Assuntos
Adenosina/análogos & derivados , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Adenosina/química , Adenosina/metabolismo , Animais , Sequência de Bases , Diferenciação Celular/genética , Células Cultivadas , Epigênese Genética , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Modelos Biológicos , Processamento Pós-Transcricional do RNA , RNA Longo não Codificante/química , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Stem Cells ; 36(3): 325-336, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29205638

RESUMO

Clarifying the regulatory mechanisms of embryonic stem cell (ESC) neural differentiation is helpful not only for understanding neural development but also for obtaining high-quality neural progenitor cells required by stem cell therapy of neurodegenerative diseases. Here, we found that long noncoding RNA 1604 (lncRNA-1604) was highly expressed in cytoplasm during neural differentiation, and knockdown of lncRNA-1604 significantly repressed neural differentiation of mouse ESCs both in vitro and in vivo. Bioinformatics prediction and mechanistic analysis revealed that lncRNA-1604 functioned as a novel competing endogenous RNA of miR-200c and regulated the core transcription factors ZEB1 and ZEB2 during neural differentiation. Furthermore, we also demonstrated the critical role of miR-200c and ZEB1/2 in mouse neural differentiation. Either introduction of miR-200c sponge or overexpression of ZEB1/2 significantly reversed the lncRNA-1604 knockdown-induced repression of mouse ESC neural differentiation. Collectively, these findings not only identified a previously unknown role of lncRNA-1604 and ZEB1/2 but also elucidated a new regulatory lncRNA-1604/miR-200c/ZEB axis in neural differentiation. Stem Cells 2018;36:325-336.


Assuntos
MicroRNAs/metabolismo , Neurônios/citologia , Neurônios/metabolismo , RNA Longo não Codificante/metabolismo , Homeobox 2 de Ligação a E-box com Dedos de Zinco/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Linhagem Celular , Biologia Computacional/métodos , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Camundongos , MicroRNAs/genética , RNA Longo não Codificante/genética , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética
11.
Sci Rep ; 7: 39527, 2017 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-28155862

RESUMO

DNA methylation and histone methylation (H3K27me3) have been reported as major barriers to induced pluripotent stem cell (iPSC) generation using four core transcription factors (Oct4, Sox2, Klf4, and c-Myc, termed OSKM). Here, to illustrate the possibility of deriving iPSCs via demethylation, as well as the exact effects of DNA methylation and histone modification on gene expression regulation, we performed RNA sequencing to characterize the transcriptomes of ES cells and iPSCs derived by demethylation with miR-29b or shDnmt3a, and carried out integrated analyses. Results showed that OSKM + miR-29b-iPSC was more close to ES cells than the others, and up-regulated genes typically presented with methylated CpG-dense promoters and H3K27me3-enriched regions. The differentially expressed genes caused by introduction of DNA demethylation during somatic cell reprogramming mainly focus on stem cell associated GO terms and KEGG signaling pathways, which may decrease the tumorigenesis risk of iPSCs. These findings indicated that DNA methylation and histone methylation have synergetic effects on regulating gene expression during iPSC generation, and demethylation by miR-29b is better than shDnmt3a for iPSC quality. Furthermore, integrated analyses are superior for exploration of slight differences as missed by individual analysis.


Assuntos
Metilação de DNA , Regulação da Expressão Gênica , Código das Histonas , Histonas/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Animais , Linhagem Celular , Fator 4 Semelhante a Kruppel , Camundongos , MicroRNAs , Transcriptoma
12.
J Agric Food Chem ; 61(7): 1542-53, 2013 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-23330536

RESUMO

The influence of a prefermentative freezing process on changes of aromatic characteristics and volatile compounds in Meili wines was studied to optimize freezing parameters and reveal the mathematical relationship between aromatic characteristics and volatile compounds. The wines obtained were characterized by sensory evaluation and stir bar sorptive extraction (SBSE) followed by a thermal desorption-gas chromatography-mass spectrometry analysis. A total of 28 aromatic descriptors from 6 categories of wine aroma terminology were identified by judging with high "modified frequency (MF%)". In addition, 19 varietal aroma compounds and 36 fermentation aroma compounds were quantitated, followed by the determination of odor activity values (OAVs). On the basis of the data obtained, principal component analysis (PCA) was used to find the relationship between characteristic aroma terms and different freezing conditions, and then partial least-squares regression (PLSR) was proposed to establish the mathematical relationship between the resulting terms and impact odorants. Natural thawing treatment on frozen must resulted in higher aroma quality with higher extraction of varietal aroma compounds. Lower frozen maceration temperature contributed to higher esters and organic acids. Impact aroma compounds were related to models for floral, sweet fruit, temperate fruit, and vegetal, whereas the model of rose and strawberry contained only varietal volatile compounds, and temperate fruit could be regressed by impact fermentation aroma compounds.


Assuntos
Fermentação , Congelamento , Odorantes/análise , Vinho/análise , Fragaria/química , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Análise dos Mínimos Quadrados , Rosa/química , Paladar/fisiologia , Vitis/química , Compostos Orgânicos Voláteis/análise
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