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1.
Toxins (Basel) ; 15(8)2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-37624249

RESUMEN

In this study, a dual-member bacterial consortium with the ability to oxidize deoxynivalenol (DON) to 3-keto-DON, designated SD, was first screened from the feces of Tenebrio molitor larvae. This consortium consisted of Pseudomonas sp. SD17-1 and Devosia sp. SD17-2, as determined by 16S rRNA-based phylogenetic analysis. A temperature of 30 °C, a pH of 8.0-9.0, and an initial inoculum concentration ratio of Devosia to Pseudomonas of 0.1 were optimal single-factor parameters for the DON oxidation activity of the bacterial consortium SD. Genome-based bioinformatics analysis revealed the presence of an intact PQQ biosynthesis operon (pqqFABCDEG) and four putative pyrroloquinoline quinone (PQQ)-dependent alcohol dehydrogenase (ADH) genes in the genomes of Pseudomonas strain SD17-1 and Devosia strain SD17-2, respectively. Biochemical analyses further confirmed the PQQ-producing phenotype of Pseudomonas and the DON-oxidizing enzymatic activities of two of four PQQ-dependent ADHs in Devosia. The addition of PQQ-containing a cell-free fermentation supernatant from Pseudomonas activated DON-oxidizing activity of Devosia. In summary, as members of the bacterial consortium SD, Pseudomonas and Devosia play indispensable and complementary roles in SD's oxidation of DON. Specifically, Pseudomonas is responsible for producing the necessary PQQ cofactor, whereas Devosia expresses the PQQ-dependent DON dehydrogenase, together facilitating the oxidation of DON.


Asunto(s)
Tenebrio , Animales , Filogenia , ARN Ribosómico 16S , Biotransformación , Heces , Larva , Cofactor PQQ , Pseudomonas/genética
2.
Toxins (Basel) ; 15(6)2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37368668

RESUMEN

Deoxynivalenol (DON) is frequently detected in cereals and cereal-based products and has a negative impact on human and animal health. In this study, an unprecedented DON-degrading bacterial isolate D3_3 was isolated from a sample of Tenebrio molitor larva feces. A 16S rRNA-based phylogenetic analysis and genome-based average nucleotide identity comparison clearly revealed that strain D3_3 belonged to the species Ketogulonicigenium vulgare. This isolate D3_3 could efficiently degrade 50 mg/L of DON under a broad range of conditions, such as pHs of 7.0-9.0 and temperatures of 18-30 °C, as well as during aerobic or anaerobic cultivation. 3-keto-DON was identified as the sole and finished DON metabolite using mass spectrometry. In vitro toxicity tests revealed that 3-keto-DON had lower cytotoxicity to human gastric epithelial cells and higher phytotoxicity to Lemna minor than its parent mycotoxin DON. Additionally, four genes encoding pyrroloquinoline quinone (PQQ)-dependent alcohol dehydrogenases in the genome of isolate D3_3 were identified as being responsible for the DON oxidation reaction. Overall, as a highly potent DON-degrading microbe, a member of the genus Ketogulonicigenium is reported for the first time in this study. The discovery of this DON-degrading isolate D3_3 and its four dehydrogenases will allow microbial strains and enzyme resources to become available for the future development of DON-detoxifying agents for food and animal feed.


Asunto(s)
Rhodobacteraceae , Tenebrio , Animales , Humanos , Larva , Cofactor PQQ , Filogenia , ARN Ribosómico 16S/genética , Oxidorreductasas , Estrés Oxidativo
3.
RSC Adv ; 12(51): 33049-33055, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36425205

RESUMEN

ZnO based transparent conducting oxides are important as they provide an alternative to the more expensive Sn : In2O3 that currently dominates the industry. Here, we investigate B-doped ZnO thin films grown via aerosol assisted chemical vapour deposition. B : ZnO films were produced from zinc acetate and triethylborane using either tetrahydrofuran or methanol (MeOH) as the solvent. The lowest resistivity of 5.1 × 10-3 Ω cm along with a visible light transmittance of ∼75-80% was achieved when using MeOH as the solvent. XRD analysis only detected the wurtzite phase of ZnO suggesting successful solid solution formation with B3+ substituting Zn2+ sites in the lattice. Refinement of the XRD patterns showed minimal distortion to the ZnO unit cell upon doping when MeOH was the solvent due to the immiscibility of the [BEt3] solution (1.0 M solution in hexane) in methanol that limited the amount of B going into the films, thus preventing excessive doping.

4.
Ann Transl Med ; 10(8): 454, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35571440

RESUMEN

Background: Osteoarthritis (OA) is one of the most common chronic diseases today, and its prevalence and incidence are expected to increase as life expectancy increases. By investigating the inhibition of long non-coding RNA maternally expressed gene 3 (lncRNA MEG3) in OA, we hope to provide some new insights into the treatment of osteoarthritis. Methods: By constructing an osteoarthritis model, the knee joint tissue of the model was observed using hematoxylin and eosin staining (HE) and computed tomography (CT). Detection of miR-34a and Klotho expression by fluorescent quantitative polymerase chain reaction (PCR) and Western blot. The lncRNA MEG3 overexpression vector was constructed and transfected into C28/I2 cells. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to detect the results of lncRNA MEG3 and miR-34a expression in each group of cells, and Western blot was used to detect the results of Klotho, recombinant fibroblast growth factor 23 (FGF23), B-cell lymphoma-2 (Bcl-2), BCL2-associated X (Bax), Transforming growth factor beta 1 (TGF-ß1), cysteinyl aspartate specific proteinase 3 (Caspase3) and cysteinyl aspartate specific proteinase 8 (Caspase8) protein expression. Results: Compared with the control group, HE and CT results showed significant pathological changes in the knee joint of the osteoarthritis model mice. and Klotho expression was significantly decreased and miR-34a expression was significantly increased in the model group (P<0.05). Compared with those in the control group, the expression levels of lncRNA MEG3, Klotho, FGF23, and Bcl-2 decreased significantly and the expression levels of microRNA-34a (miR-34a), Bax, TGF-ß1, Caspase 3, and Caspase 8 increased sharply (P<0.05) in the lipopolysaccharides (LPS) group. Meanwhile, lncRNA MEG3 overexpression upregulated the expression of miR-34a, Bax, TGF-ß1, Caspase3 and Caspase8, and downregulated the expression of Klotho, FGF23 and Bcl-2. Conclusions: lncRNA MEG3 regulated the expression of FGF23, Bcl-2, Bax, TGF-ß1, Caspase 3, and Caspase 8 by regulating the miR-34a/Klotho axis, thereby affecting the progress of OA.

5.
RSC Adv ; 10(57): 34527-34533, 2020 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-35514390

RESUMEN

Extrinsically doped ZnO thin films are of interest due to their high electrical conductivity and transparency to visible light. In this study, P doped ZnO thin films were grown on glass substrates via aerosol assisted chemical vapour deposition. The results show that P is a successful dopant for ZnO in the V+ oxidation state and is able to reduce resistivity to 6.0 × 10-3 Ω cm while maintaining visible light transmittance at ∼75%. The thins films were characterized by X-ray diffraction studies that showed only Bragg peaks for the wurtzite ZnO phase. Fitting of the diffraction data to a Le Bail model also showed a general expansion of the ZnO unit cell upon doping due to the substitution of Zn2+ ions with the larger P5+.

7.
Pestic Biochem Physiol ; 145: 15-21, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29482727

RESUMEN

Resistance to benzimidazole fungicides in many phytopathogenic fungi is caused by specific point mutations in the ß-tubulin gene (ß-tubulin). However, the mutated locus and genotype of ß-tubulin differ among phytopathogenic fungi. To validate the point mutation in Fusarium asiaticum ß2-tubulin that confers resistance to carbendazim and to analyze the molecular interaction between carbendazim and F. asiaticum ß2-tubulin. In this study, a new point mutation (GAG→GCG, E198A) at codon 198 of ß2-tubulin in a wild-type F. asiaticum strain was constructed by site-directed mutagenesis followed by a split marker strategy. The site-directed mutants were verified and exhibited a high level of resistance to carbendazim. In the absence of fungicide treatment, the biological characteristics did not differ between the site-directed mutants and the wild-type strain. Molecular docking between carbendazim and ß2-tubulin was carried out using the Surflex-Dock program in Sybyl X-2.0 version and the results indicated that the E198A mutation altered the configuration of ß2-tubulin, resulting in the change of the bonding sites and docking scores. We concluded that the point mutation of F. asiaticum ß2-tubulin conferring carbendazim resistance may not always be the bonding site for carbendazim.


Asunto(s)
Bencimidazoles/farmacología , Carbamatos/farmacología , Farmacorresistencia Fúngica/genética , Fungicidas Industriales/farmacología , Fusarium/efectos de los fármacos , Mutación Puntual , Tubulina (Proteína)/genética , Sitios de Unión , Fusarium/genética , Genes de Plantas , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Mutagénesis Sitio-Dirigida , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
8.
Plant Dis ; 102(7): 1234-1239, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30673573

RESUMEN

This study evaluated the use of phenamacril and ipconazole, alone and in mixtures, for the control of rice bakanae disease caused by Fusarium fujikuroi. Mixtures were studied with the goal of reducing the selection of fungicide-resistant field isolates of the fungus. When tested alone, both phenamacril and ipconazole exhibited high antifungal activity against F. fujikuroi mycelial growth; the average EC50 value for 19 field isolates was 0.1544 µg/ml for phenamacril and 0.0472 µg/ml for ipconazole. A 2:1 mixture of phenamacril and ipconazole caused a slightly synergistic (greater than additive) inhibition of mycelial growth. Inhibition of F. fujikuroi sporulation was highest for ipconazole alone, intermediate with the 2:1 mixture, and lowest for phenamacril alone. Inhibition by phenamacril and ipconazole alone or by the 2:1 mixture was substantially lower for spore germination than for mycelial growth or sporulation. When the total fungicide concentration was <24 g of a.i./100 kg of treated rice seeds, the fungicides, whether alone or in the 2:1 mixture, were not phytotoxic to seeds or seedlings of two rice cultivars. In a greenhouse experiment, the 2:1 mixture of phenamacril and ipconazole at 6 g of a.i./100 kg of treated seeds provided 100% control of rice bakanae disease on two cultivars. Overall, the results indicate that the use of a 2:1 mixture of phenamacril and ipconazole should control rice bakanae disease while reducing the occurrence of fungicide resistance in F. fujikuroi.


Asunto(s)
Fungicidas Industriales/farmacología , Fusarium/fisiología , Oryza/microbiología , Enfermedades de las Plantas/microbiología , Sinergismo Farmacológico , Fusarium/clasificación , Fusarium/efectos de los fármacos , Interacciones Huésped-Patógeno/efectos de los fármacos , Micelio/efectos de los fármacos , Micelio/fisiología , Plantones/microbiología , Semillas/microbiología , Especificidad de la Especie , Esporas Fúngicas/efectos de los fármacos , Esporas Fúngicas/fisiología
9.
Pest Manag Sci ; 72(11): 2128-2135, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26823005

RESUMEN

BACKGROUND: The point mutation at codon 200 (TTC→TAC, F200Y) of the ß2 -tubulin gene confers resistance to benzimidazole fungicide in Fusarium asiaticum. These isolates with this mutation have been detected mainly by determining the minimum inhibitory concentration (MIC) of fungicides, which is always time consuming, tedious and inefficient. RESULTS: A visual, rapid and efficient method with high specificity was developed, based on loop-mediated isothermal amplification (LAMP). Six sets of LAMP primers were designed, and one set was optimised specifically to distinguish the F200Y mutant genotype. With the optimal LAMP primers, concentrations of LAMP components were optimised. The optimal reaction conditions were 57-64 °C for 75 min. The feasibility of the LAMP assay for detection of the F200Y mutant genotype of F. asiaticum was demonstrated by assaying diseased wheat spikelets that were artificially inoculated in the field. CONCLUSION: The new LAMP assay had good specificity, sensitivity, stability and repeatability. It will be useful for assessing the risk of F. asiaticum populations with carbendazim resistance developing in the field, and will also provide important reference data for integrated control of Fusarium head blight caused by F. asiaticum. © 2016 Society of Chemical Industry.


Asunto(s)
Bencimidazoles/farmacología , Fungicidas Industriales/farmacología , Fusarium/efectos de los fármacos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Mutación Puntual , Farmacorresistencia Fúngica , Fusarium/genética , Genotipo
10.
Plant Dis ; 100(5): 976-983, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-30686158

RESUMEN

The point mutation at codon 200 (TTC→TAC, F200Y) confers moderate resistance to carbendazim in Sclerotinia sclerotiorum. This mutant genotype (F200Y) has been detected mainly by determining the minimum inhibitory concentration (MIC), which requires 3 to 5 days. Here, we developed a loop-mediated isothermal amplification (LAMP) assay for the rapid detection of the F200Y mutant genotype of carbendazim-resistant isolates of S. sclerotiorum. Specific LAMP primers were designed and concentrations of LAMP components were optimized. The optimal reaction conditions were 62 to 63°C for 45 min. The new LAMP assay requires no special equipment and is highly sensitive and specific (the i.e., it generated positive results with F200Y mutant genotype but generated negative results with other carbendazim-resistant mutants and with a variety of carbendazim-resistant mutants of Botrytis cinerea and Fusarium graminearum). Inclusion of the loop backward (LB) primer reduced the reaction time to 15 min. Results were identical with LAMP and MIC determinations. The advantages of the LB-accelerated LAMP assay for detection of the F200Y mutant genotype were demonstrated by assaying sclerotia produced on rape stems that were artificially inoculated in the field. The results indicated that the new LAMP assay represents an improved way to detect the F200Y mutant genotype of carbendazim-resistant isolates of S. sclerotiorum.

11.
ACS Appl Mater Interfaces ; 7(41): 23278-90, 2015 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-26430876

RESUMEN

To enhance the efficacy and optimize the treatment of cancers, the integration of multimodal treatment strategies leading to synergistic effects is a promising approach. The coassembly of multifunctional agents for systematic therapies has received considerable interest in cancer treatment. Herein, Ru(II) complex-functionalized single-walled carbon nanotubes (Ru@SWCNTs) are developed as nanotemplates for bimodal photothermal and two-photon photodynamic therapy (PTT-TPPDT). SWCNTs have the ability to load a great amount of Ru(II) complexes (Ru1 or Ru2) via noncovalent π-π interactions. The loaded Ru(II) complexes are efficiently released by the photothermal effect of irradiation from an 808 nm diode laser (0.25 W/cm(2)). The released Ru(II) complexes produce singlet oxygen species ((1)O2) upon two-photon laser irradiation (808 nm, 0.25 W/cm(2)) and can be used as a two-photon photodynamic therapy (TPPDT) agent. Based on the combination of photothermal therapy and two-photon photodynamic therapy, Ru@SWCNTs have greater anticancer efficacies than either PDT using Ru(II) complexes or PTT using SWCNTs in two-dimensional (2D) cancer cell and three-dimensional (3D) multicellular tumor spheroid (MCTS) models. Furthermore, in vivo tumor ablation is achieved with excellent treatment efficacy under a diode laser (808 nm) irradiation at the power density of 0.25 W/cm(2) for 5 min. This study examines an efficacious bimodal PTT and TPPDT nanoplat form for the development of cancer therapeutics.


Asunto(s)
Hipertermia Inducida , Rayos Infrarrojos , Nanotubos de Carbono/química , Fotoquimioterapia , Rutenio/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Espectroscopía de Resonancia por Spin del Electrón , Endocitosis/efectos de los fármacos , Femenino , Células HeLa , Humanos , Ratones Desnudos , Nanotubos de Carbono/ultraestructura , Fotones , Oxígeno Singlete/química , Espectrofotometría Ultravioleta , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/patología
12.
Chemistry ; 21(43): 15308-19, 2015 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-26338207

RESUMEN

Hypoxia is the critical feature of the tumor microenvironment that is known to lead to resistance to many chemotherapeutic drugs. Six novel ruthenium(II) anthraquinone complexes were designed and synthesized; they exhibit similar or superior cytotoxicity compared to cisplatin in hypoxic HeLa, A549, and multidrug-resistant (A549R) tumor cell lines. Their anticancer activities are related to their lipophilicity and cellular uptake; therefore, these physicochemical properties of the complexes can be changed by modifying the ligands to obtain better anticancer candidates. Complex 1, the most potent member of the series, is highly active against hypoxic HeLa cancer cells (IC50 =0.53 µM). This complex likely has 46-fold better activity than cisplatin (IC50 =24.62 µM) in HeLa cells. This complex tends to accumulate in the mitochondria and the nucleus of hypoxic HeLa cells. Further mechanistic studies show that complex 1 induced cell apoptosis during hypoxia through multiple pathways, including those of DNA damage, mitochondrial dysfunction, and the inhibition of DNA replication and HIF-1α expression, making it an outstanding candidate for further in vivo studies.


Asunto(s)
Antraquinonas/química , Antraquinonas/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Neoplasias Pulmonares/química , Rutenio/química , Línea Celular Tumoral , Células HeLa , Células Hep G2 , Humanos , Hipoxia , Ligandos , Neoplasias Pulmonares/tratamiento farmacológico
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