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1.
New Phytol ; 244(3): 825-839, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39169597

RESUMO

Plants frequently encounter adverse conditions and stress during their lives. Abscisic acid (ABA) plays a crucial role in response to salt stress, and dynamic regulation of ABA levels is essential for plant growth and stress resistance. In this study, we identified a transcription factor, OsSGL (Oryza sativa Stress tolerance and Grain Length), which acts as a negative regulator in salt stress, controlling ABA synthesis. OsSGL-overexpressing and mutant materials exhibited sensitivity and tolerance to salt stress, respectively. Notably, under salt treatment, several ABA-related genes, including the ABA synthesis enzyme OsNCED3 and the ABA response gene OsRAB21, were bound by OsSGL, leading to the inhibition of their transcription. Additionally, we found that a key enzyme involved in glycolysis, OsGAPC1, interacted with OsSGL and enhanced the inhibitory effect of OsSGL on OsNCED3. Upon salt stress, OsGAPC1 underwent acetylation and then translocated from the nucleus to the cytoplasm, partially alleviating the inhibitory effect of OsSGL on OsNCED3. Identification of the OsGAPC1-OsSGL module revealed a negative regulatory mechanism involved in the response of rice to salt stress. This discovery provides insight into the dynamic regulation of ABA synthesis in plants under salt stress conditions, highlighting the delicate balance between stress resistance and growth regulation.


Assuntos
Ácido Abscísico , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Tolerância ao Sal , Oryza/genética , Oryza/fisiologia , Oryza/efeitos dos fármacos , Oryza/metabolismo , Ácido Abscísico/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Tolerância ao Sal/genética , Tolerância ao Sal/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Estresse Salino , Acetilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Estresse Fisiológico/genética , Estresse Fisiológico/efeitos dos fármacos , Plantas Geneticamente Modificadas
2.
Opt Express ; 32(5): 7079-7089, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439398

RESUMO

A compound resonant cavity-type single longitudinal mode erbium-doped fiber laser is proposed and verified in this paper. We use a compound four-cavity to expand the longitudinal mode spacing of the laser and a homemade grating F-P filter and a saturable absorber to narrow the gain spectral bandwidth, enabling the laser to operate in a single-frequency state. Through theoretical analysis and experimental verification of the important roles of the main constructed fiber laser parts, the center wavelength of the laser output of 1550.06 nm is obtained, and the optical signal-to-noise ratio is 65 dB. In a 50 minute period, the wavelength fluctuation is exhibited along with the maximum power fluctuation of 0.28 dB. The value of the laser output linewidth is ∼250 Hz, measured by using the delayed self-heterodyne method.

3.
Luminescence ; 39(3): e4717, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38504447

RESUMO

Tetracyclines are currently the most commonly used class of antibiotics, and their residue issue significantly impacts public health safety. In this study, a surface modification of perovskite with cetyltrimethylammonium bromide led to the generation of stable electrochemiluminescence (ECL) emitters in aqueous systems and improved the biocompatibility of perovskite. A perovskite quantum dot-based ECL sensing strategy was developed. Utilizing the corresponding aptamer of the antibiotics, strain displacement reactions were triggered, disrupting the ECL quenching system composed of perovskite and Ag nanoclusters (Ag NCs) on the electrode surface, generating a signal to achieve quantitative detection of several common tetracycline antibiotics. The perovskite quantum dot provided a strong and stable initial signal, while the efficient catalytic activity of the silver cluster enhanced the recognition sensitivity. Tetracycline, chlortetracycline, and oxytetracycline were used as examples to demonstrate the differentiation and quantitative detection through this method. In addition, the aptasensor exhibited analytical performance with the linear range (0.1-10 µM OTC) and good recovery rates of 94.7% to 101.6% in real samples. This approach has the potential to become a sensitive and practical approach for assessing antibiotic residues.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Compostos de Cálcio , Nanopartículas Metálicas , Óxidos , Titânio , Tetraciclina , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Antibacterianos , Tetraciclinas , Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química , Aptâmeros de Nucleotídeos/química
4.
Nano Lett ; 23(24): 11809-11817, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38048290

RESUMO

Insect sex pheromones as an alternative to chemical pesticides hold promising prospects in pest control. However, their burst release and duration need to be optimized. Herein, pheromone-loaded core-shell fibers composed of degradable polycaprolactone and polyhydroxybutyrate were prepared by coaxial electrospinning. The results showed that this core-shell fiber had good hydrophobic performance and thermal stability, and the light transmittance in the ultraviolet band was only below 40%, which provided protection to pheromones. The core-shell structure alleviated the burst release of pheromone in the fiber and extended the release time to about 133 days. In the field, the pheromone-loaded core-shell fibers showed the same continuous and efficient trapping of Spodoptera litura as the commercial carriers. More importantly, the electrospun fibers combined with biomaterials had a degradability unmatched by commercial carriers. The structure design strategy provides ideas for the innovative design of pheromone carriers and is a potential tool for the management of agricultural pests.


Assuntos
Materiais Biocompatíveis , Feromônios
5.
J Sep Sci ; 46(8): e2200984, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36795010

RESUMO

Phorbol is a tetracyclic diterpenoid found in Euphorbia tirucalli, Croton tiglium, and Rehmannia glutinosa, and is nuclear of various phorbol esters. The rapid obtaining of phorbol with high purity highly contributes to its application, such as synthesizing phorbol esters with designable side chains and particular therapeutic efficacy. This study introduced a biphasic alcoholysis method for obtaining phorbol from croton oil by using polarity imparity organic solvents in both phases and established a high-speed countercurrent chromatography method for simultaneous separation and purification of phorbol. The optimized operation conditions of biphasic alcoholysis were a reaction time of 91 min, a temperature of 14°C, and a croton oil-methanol ratio of 1:30 (g:ml). The phorbol during the biphasic alcoholysis was 3.2-fold higher in content than that obtained in conventional monophasic alcoholysis. The optimized high-speed countercurrent chromatography method was using the ethyl acetate/n-butyl alcohol/water at 4.7:0.3:5 (v:v:v) with Na2 SO4 at 0.36 g/10 ml as the solvent system, using the mobile phase flow rate of 2 ml/min, the revolution of 800 r/min, under which the retention of the stationary phase was achieved at 72.83%. The crystallized phorbol following high-speed countercurrent chromatography was obtained as high purity of 94%.


Assuntos
Distribuição Contracorrente , Forbóis , Distribuição Contracorrente/métodos , Óleo de Cróton , Solventes/química , Extratos Vegetais/química , Ésteres de Forbol , Cromatografia Líquida de Alta Pressão
6.
Lett Appl Microbiol ; 76(2)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36787890

RESUMO

Severe infection with multidrug-resistant Enterobacterales caused by the plasmid-induced colistin resistance gene MCR-1 is a serious public health challenge. In this case, it is necessary and pressing to find a treatment to overcome antibiotic resistance. Here, we investigated the synergistic effect and mechanism of loperamide combined with colistin against MCR-1-positive pathogens. We evaluated the combined effect of loperamide and colistin using the checkerboard method and the time-kill experiment. The results showed that loperamide could enhance the bactericidal ability of colistin, and this combination regimen could completely kill the tested bacteria within 4 h. Subsequently, spectrofluorimetric methods were used to explore the mechanism of loperamide combined with colistin. The results indicated that the mode of action of loperamide combined with colistin was found to involve mechanical disruption of the membrane. Furthermore, molecular simulation and microscale thermophoresis results revealed that loperamide reduced the impact of MCR-1 protein by directly binding to its active site. In addition, the combined regimen of loperamide and colistin effectively reduced the bacterial load in the thighs of mice while increasing the protection rate by 70%. In short, as a potential lead compound, loperamide can enhance the killing effect of colistin on pathogenic Enterobacterales carrying MCR-1 by causing membrane damage and inhibiting MCR-1 protein activity.


Assuntos
Colistina , Proteínas de Escherichia coli , Animais , Camundongos , Colistina/farmacologia , Loperamida , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Testes de Sensibilidade Microbiana , Plasmídeos , Proteínas de Escherichia coli/genética
7.
Phytother Res ; 37(11): 5378-5393, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37589332

RESUMO

Epinodosin has shown antibacterial and antitumor biological characteristics in the documents. We found that Epinodosin has an effective inhibitory effect on esophageal squamous cell carcinoma (ESCC). However, the potential roles and mechanisms of Epinodosin in ESCC remain unclear. We performed many experiments to clarify the effect and mechanism of Epinodosin on ESCC. In this study, cell viability, invasion, migration, and apoptosis were determined by 3-(4,5-dimethyl-2-thiazolyl)-2,-diphenytetrazoliumromide (MTT), Transwell, and flow cytometry. The differentially expressed miRNAs were screened through RNA transcriptome sequencing. The expression levels of miRNA-143-3p and some proteins were measured by real-time polymerase chain reaction (PCR) and Western blot. The anticancer effects of Epinodosin in vivo were determined by a nude mouse model. Epinodosin suppressed cell proliferation/invasion/migration and induced ESCC cell apoptosis. Epinodosin remarkably affected the protein expression of mitogen-activated protein kinase (MAPK) signaling pathway. The animal experiments demonstrated that Epinodosin could attenuate the growth of ESCC tumors in nude mice. The expression of p53, Bim, and Bax was upregulated, while that of Bcl-2 was downregulated in tumor tissues. In conclusion, Epinodosin suppresses cell viability/invasion/migration, while induces ESCC cell apoptosis by mediating miRNA-143-3p and Bcl-2, and can markedly attenuate the growth of ESCC tumors in nude mice.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , Animais , Camundongos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/patologia , Carcinoma de Células Escamosas/tratamento farmacológico , Camundongos Nus , Neoplasias Esofágicas/tratamento farmacológico , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica
8.
J Immunol ; 204(7): 1736-1745, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32111731

RESUMO

IL-37 is a newly identified immune-suppressive factor; however, the function, cellular sources, and mechanism of IL-37 in humoral immunity and Myasthenia gravis (MG) are still unclear. In this study, we found IL-37 were substantially downregulated in the serum and PBMCs of MG patients compared with healthy controls. The lower IL-37 was associated with severer disease (quantitative MG score) and higher follicular Th (Tfh)/Tfh17 and B cell numbers. Flow cytometry analysis revealed that IL-37 was mainly produced by CD4+ T cells without overlapping with Th1, Th17, and Tfh subsets in MG patients. Regulatory IL-37+ T cell rarely expressed Foxp3 and CD25 but produced numerous IL-4. Tfh and B cell expressed high levels of SIGIRR, the receptor of IL-37, in MG patients. Mechanically, IL-37 directly bond to SIGIRR, repressed the proliferation, cytokine production of Tfh and B cells, and the secretion of autoantibody via inhibition of STAT3 signaling in Tfh and B cells.


Assuntos
Autoimunidade/imunologia , Linfócitos B/imunologia , Interleucina-1/imunologia , Miastenia Gravis/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Células Th17/imunologia , Adulto , Autoanticorpos/imunologia , Células Cultivadas , Feminino , Humanos , Imunidade Humoral/imunologia , Masculino , Pessoa de Meia-Idade
9.
Drug Dev Res ; 83(2): 432-446, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34636432

RESUMO

Paeonol exerted an effect in lung cancer, but the underlying mechanism remained vague. In this research, we assessed the effects of Paeonol and microRNA (miR)-126-5p on the viability, migration, invasion, and epithelial-mesenchymal transition (EMT) of lung cancer cells. Lung cancer cells and BEAS-2B cells were treated with Paeonol, and viability was detected by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide (MTT) assay. The migration and invasion of lung cancer cells after treatment with Paeonol at 40 µg/mL or 80 µg/mL were detected by wound healing assay and Transwell assay, respectively. The effects of Paeonol on transforming growth factor-ß1 (TGF-ß1)-induced EMT and relative expressions of EMT-related proteins were determined using Western blot. The target gene of miR-126-5p and the binding sites between them were predicted by TargetScan, and confirmed using dual-luciferase reporter assay. Relative expressions of miR-126-5p, its target gene and EMT-related proteins were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Rescue assay was performed to analyze the relation between Paeonol and miR-126-5p. Paeonol down-regulated cell viability and inhibited migration, invasion and TGF-ß1-induced EMT while up-regulating miR-126-5p expression in lung cancer cells as the dose increased. However, miR-126-5p inhibitor could reverse the effect of Paeonol. ZEB2 was the target gene of miR-126-5p, and silencing ZEB2 expression reversed the effects of miR-126-5p downregulation. Paeonol also regulated the expression of ZEB2 in lung cancer cells, and this regulation depends on the regulation of miR-126-5p. Paeonol inhibits human lung cancer cell viability and metastasis via the miR-126-5p/ZEB2 axis, and could be adopted as a potential agent for lung cancer treatment.


Assuntos
Neoplasias Pulmonares , MicroRNAs , Acetofenonas , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Fator de Crescimento Transformador beta1/metabolismo , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genética , Homeobox 2 de Ligação a E-box com Dedos de Zinco/metabolismo
10.
Molecules ; 27(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36364136

RESUMO

In order to improve the mechanical strength and imprinting efficiency, a novel bovine serum albumin (BSA) molecularly imprinted poly(ionic liquid)/calcium alginate composite cryogel membrane (MICM) was prepared. The results of the tensile test indicated that the MICM had excellent mechanical strength which could reach up to 90.00 KPa, 30.30 times higher than the poly (ionic liquid) membrane without calcium alginate; the elongation of it could reach up to 93.70%, 8.28 times higher than the poly (ionic liquid) membrane without calcium alginate. The MICM had a very high welling ratio of 1026.56% and macropore porosity of 62.29%, which can provide effective mass transport of proteins. More remarkably, it had a very high adsorption capacity of 485.87 mg g-1 at 20 °C and 0.66 mg mL-1 of the initial concentration of BSA. Moreover, MICM also had good selective and competitive recognition toward BSA, exhibiting potential utility in protein separation. This work can provide a potential method to prepare the protein-imprinted cryogel membrane with both high mechanical strength and imprinting efficiency.


Assuntos
Líquidos Iônicos , Impressão Molecular , Criogéis , Soroalbumina Bovina , Alginatos , Impressão Molecular/métodos , Adsorção
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