Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Plant Physiol ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507576

RESUMO

Grapevine (Vitis vinifera L.) incurs severequality degradation and yield loss from powdery mildew, a major fungal disease caused by Erysiphe necator. ENHANCED DISEASE RESISTANCE1 (EDR1), a Raf-like mitogen-activated protein kinase kinase kinase (MAPKKK), negatively regulates defense responses against powdery mildew in Arabidopsis (Arabidopsis thaliana). However, little is known about the role of the putatively orthologous EDR1 gene in grapevine. In this study, we obtained grapevine VviEDR1-edited lines using CRISPR/Cas9. Plantlets containing homozygous and bi-allelic indels in VviEDR1 developed leaf lesions shortly after transplanting into the soil and died at the seedling stage. Transgenic plants expressing wild-type VviEDR1 and mutant Vviedr1 alleles as chimera (designated as VviEDR1-chi) developed normally and displayed enhanced resistance to powdery mildew. Interestingly, VviEDR1-chi plants maintained a spatiotemporally distinctive pattern of VviEDR1 mutagenesis: while almost no mutations were detected from terminal buds, ensuring normal function of the apical meristem, mutations occurred in young leaves and increased as leaves matured, resulting in resistance to powdery mildew. Further analysis showed that the resistance observed in VviEDR1-chi plants was associated with callose deposition, increased production of salicylic acid (SA) and ethylene (ET), H2O2 production and accumulation, and host cell death. Surprisingly, no growth penalty was observed with VviEDR1-chi plants. Hence, this study demonstrated a role of VviEDR1 in the negative regulation of resistance to powdery mildew in grapevine and provided an avenue for engineering powdery mildew resistance in grapevine.

2.
J Gene Med ; 26(1): e3587, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37697474

RESUMO

BACKGROUND: Cytotoxic T-lymphocyte (CTL)-mediated therapy has become the central theme of cancer immunotherapy. The present study emphasized the role of CTLs in acute myeloid leukemia (AML) and aimed to understand the role of CTLs cytogenetic markers in monitoring AML prognostic outcomes and clinical treatment responses. METHODS: Seurat was employed to analyze single-cell RNA sequencing data in GSE116256. CellChat was used to detect cell-cell interactions to determine the central role of CTLs. The marker genes of CTLs were extracted and randomForestSRC was employed to construct a random forest model. The prognosis, immune checkpoint expression, immune cell infiltration, immunotherapy response and drug sensitivity of AML patients were evaluated according to the model. RESULTS: Seven types of cellular components of AML were identified in GSE116256, and CTLs radiated the most interactions with other cell types. Random forest analysis screened out six marker genes for construction of the model. The risk score calculated according to the model was positively correlated with immune score, immune cell infiltration, expression of multiple immune checkpoints and immune effect pathway. The response rate of immunotherapy was significantly higher and more sensitive to 14 drugs in high-risk samples than in low-risk samples, whereas low-risk patients showed a higher sensitivity to six drugs. CONCLUSIONS: The present study emphasized the central role of CTLs in cell communication and established a random forest regression model based on its cytogenetic markers, which helps to stratify the prognosis of AML, promotes the understanding of the phenotype of AML and may also guide the treatment choice of AML patients, which contributed to stratification of AML prognosis, promoted understanding of the phenotype of AML and may guide treatment selection in patients with AML.


Assuntos
Leucemia Mieloide Aguda , Linfócitos T Citotóxicos , Humanos , Linfócitos T Citotóxicos/metabolismo , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Imunoterapia
3.
Micromachines (Basel) ; 14(10)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37893271

RESUMO

The SAW (surface acoustic wave) gyroscopic effect is a key parameter that reflects the sensitivity performance of SAW angular velocity sensors. This study found that adding a layer of non-piezoelectric material with a lower reflection coefficient than that of the upper-layer material below the piezoelectric substrate to form a double-layer structure significantly enhanced the SAW gyroscopic effect, and the smaller the reflection coefficient of the lower-layer material, the stronger the SAW gyroscopic effect, with values being reached that were two to three times those with single-layer substrate structures. This was confirmed using a three-dimensional model, and the experimental results also showed that the thickness of the piezoelectric layer and the type of the lower-layer material also had a significant impact on the SAW gyroscopic effect. This novel discovery will pave the way for the future development of SAW angular velocity sensors.

4.
Hortic Res ; 10(9): uhad163, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37746307

RESUMO

The powdery mildew (Erysiphe necator) is a prevalent pathogen hampering grapevine growth in the vineyard. An arsenal of candidate secreted effector proteins (CSEPs) was encoded in the E. necator genome, but it is largely unclear what role CSEPs plays during the E. necator infection. In the present study, we identified a secreted effector CSEP080 of E. necator, which was located in plant chloroplasts and plasma membrane. Transient expressing CSEP080 promotes plant photosynthesis and inhibits INF1-induced cell death in tobacco leaves. We found that CSEP080 was a necessary effector for the E. necator pathogenicity, which interacted with grapevine chloroplast protein VviB6f (cytochrome b6-f complex iron-sulfur subunit), affecting plant photosynthesis. Transient silencing VviB6f increased the plant hydrogen peroxide production, and the plant resistance to powdery mildew. In addition, CSEP080 manipulated the VviPE (pectinesterase) to promote pectin degradation. Our results demonstrated the molecular mechanisms that an effector of E. necator translocates to host chloroplasts and plasma membrane, which suppresses with the grapevine immunity system by targeting the chloroplast protein VviB6f to suppress hydrogen peroxide accumulation and manipulating VviPE to promote pectin degradation.

5.
Chem Soc Rev ; 52(15): 5340-5342, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37435885

RESUMO

Correction for 'Near-infrared metal agents assisting precision medicine: from strategic design to bioimaging and therapeutic applications' by Chonglu Li et al., Chem. Soc. Rev., 2023, 52, 4392-4442, https://doi.org/10.1039/D3CS00227F.

6.
Chem Soc Rev ; 52(13): 4392-4442, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37334831

RESUMO

Metal agents have made incredible strides in preclinical research and clinical applications in recent years, but their short emission/absorption wavelengths continue to be a barrier to their distribution, therapeutic action, visual tracking, and efficacy evaluation. Nowadays, the near-infrared window (NIR, 650-1700 nm) provides a more accurate imaging and treatment option. Thus, there has been ongoing research focusing on developing multifunctional NIR metal agents for imaging and therapy that have deeper tissue penetration. The design, characteristics, bioimaging, and therapy of NIR metal agents are covered in this overview of papers and reports published to date. To start with, we focus on describing the structure, design strategies, and photophysical properties of metal agents from the NIR-I (650-1000 nm) to NIR-II (1000-1700 nm) region, in order of molecular metal complexes (MMCs), metal-organic complexes (MOCs), and metal-organic frameworks (MOFs). Next, the biomedical applications brought by these superior photophysical and chemical properties for more accurate imaging and therapy are discussed. Finally, we explore the challenges and prospects of each type of NIR metal agent for future biomedical research and clinical translation.


Assuntos
Diagnóstico por Imagem , Medicina de Precisão , Metais , Corantes Fluorescentes/química , Imagem Óptica/métodos
7.
Biosens Bioelectron ; 218: 114752, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36240627

RESUMO

Innovative optoelectronics are expected to play more important role in clinical diagnosis. In this study, on the basis of sensitive gating effect by in situ enzymatic functionalization of semiconductors, a novel organic photoelectrochemical transistor (OPECT) detection of serum alkaline phosphatase (ALP) level was demonstrated. Specifically, the OPECT detection operates upon the ALP-catalyzed hydrolysis of sodium thiophosphate to yield hydrogen sulfide (H2S), which could in situ generate CdS on the TiO2 electrode in the presence of Cd2+ cations. Correlated to the ALP level, the CdS directly formed on and interfacing with the TiO2 could sensitively gating the poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) channel, allowing unique optoelectronic detection of serum ALP level with a linear range from 0.005 to 15 U L-1 and a detection limit corresponding to 0.0012 U L-1 (S/N = 3). This study offers not only an optoelectronic method for detection of serum ALP level, but also a perspective for unique OPECT gating and application. Moreover, the general catalytic abilities of enzymes to produce functional species and their rich interactions with various gate substrates further provide great space for futuristic OPECT detection in enzyme-associated diseases.


Assuntos
Técnicas Biossensoriais , Sulfeto de Hidrogênio , Fosfatase Alcalina , Cádmio , Estirenos , Limite de Detecção
8.
Biosens Bioelectron ; 217: 114700, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182837

RESUMO

Metal-organic framework (MOF) derivatives with unique physicochemical and electronic properties have seen a tremendous growth in diverse applications. Organic optobioelectronics have long been pursued in modern electronics for next-generation bio-relevant implementations. The intersection of these two disciplines could be an appealing way to pursue better performance of materials and devices. Herein this work reports the exploration of MOF derivatives and its ionic modulation for gating organic photoelectrochemical transistor (OPECT) biosensing. In the representative system of poly(ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) gated by zeolitic-imidazolate-framework (ZIF)-8-derived CdxZn1-xS, a high current gain could be achieved at zero gate bias. In connection to a CuO nanoparticle-labeled sandwich immunoassay, acidolysis-triggered Cu2+-induced ionic modulation of the system results into a good performance toward human IgG with a low limit of detection of 0.003 pg/mL. This work features the MOF derivative-gated organic electronics and is expected to inspire more interest to explore various MOF derivative electronics with unknown possibilities, considering the diversity of MOF derivatives.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Técnicas Biossensoriais/métodos , Cádmio , Humanos , Imunoensaio , Imunoglobulina G , Íons , Estruturas Metalorgânicas/química , Estirenos
9.
ACS Sens ; 7(9): 2788-2794, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36069701

RESUMO

Nature makes use of molecular charges to operate specific biological synthesis and reactions. Targeting advanced opto-bioelectronic sensors, organic photoelectrochemical transistors (OPECTs), taking advantage of the light fuel substituting an external gate potential, is now debuting and expected to serve as a universal platform for studying the rich light-biomatter interplay for new bioanalytics. Given the ubiquity of charged biomolecules in nature, molecular charge manipulation should underpin a generic route for innovative OPECT regulation and operation, which nevertheless has remained unachieved. Herein, this work manifests the biological tuning of surface charge toward the OPECT biosensor, which was exemplified by a light-sensitive CdS quantum dot (QD) gate electrode interfaced by a smart DNA superstructure with adenosine triphosphate (ATP) responsiveness. Highly negative-charged supramolecular DNA concatemers were self-assembled via sequential hybridization, and the ATP-triggered disassembly of the DNA concatemers would cause a tandem change of the effective gate voltage and transfer characteristics with significantly improved resolution. The present opto-bioelectronic device translates the events of charged molecules into amplified electrical signals and outlines a generic format for the future exploitation of rich biological tunability and light-biomatter interplay for innovative bioanalytics and beyond.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Trifosfato de Adenosina , DNA/análise , Hibridização de Ácido Nucleico , Pontos Quânticos/química
10.
Mikrochim Acta ; 188(8): 243, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34231032

RESUMO

The design and development of a 3D hierarchical CdS/NiO heterojunction and its application in a self-powered cathodic photoelectrochemical (PEC) bioanalysis is introduced. Specifically, NiO nanoflakes (NFs) were in situ formed on carbon fibers via a facile liquid-phase deposition method followed by an annealing step and subsequent integration with CdS quantum dots (QDs). The glucose oxidase (GOx) was then coated on the photocathode to allow the determination of glucose. Under 5 W 410 nm LED light and at a working voltage of 0.0 V (vs. Ag/AgCl), this method can assay glucose concentrations down to 1.77×10-9 M. The linear range was 5×10-7 M to 1×10-3 M, and the relative standard deviation (RSD) was below 5%. The photocathodic biosensor achieved target detection with high sensitivity and selectivity. This work is expected to stimulate more passion in the development of innovative hierarchical heterostructures for advanced self-powered photocathodic bioanalysis. Design of 3D hierarchical CdS/NiO heterojunction and its application in a self-powered cathodic photoelectrochemical (PEC) bioanalysis.


Assuntos
Compostos de Cádmio/química , Glucose Oxidase/metabolismo , Glucose/análise , Nanocompostos/química , Níquel/química , Sulfetos/química , Técnicas Biossensoriais , Fibra de Carbono , Técnicas Eletroquímicas , Limite de Detecção , Processos Fotoquímicos , Pontos Quânticos
12.
Sci Rep ; 10(1): 766, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964975

RESUMO

The proteasome inhibitor bortezomib is the most successfully applied chemotherapeutic drug for treating multiple myeloma. However, its clinical efficacy reduced due to resistance development. The underlying molecular mechanisms of bortezomib resistance are poorly understood. In this study, by combining in silico analysis and sgRNA library based drug resistance screening assay, we identified SENP2 (Sentrin/SUMO-specific proteases-2) as a bortezomib sensitive gene and found its expression highly downregulated in bortezomib resistant multiple myeloma patient's samples. Furthermore, down regulation of SENP2 in multiple myeloma cell line RPMI8226 alleviated bortezomib induced cell proliferation inhibition and apoptosis, whereas, overexpression of SENP2 sensitized these cells to bortezomib treatment. We further demonstrate that knockdown of SENP2 in RPMI8226 cells increased SUMO2 conjugated IκBα that resulted in the activation of NF-κB. Taken together, we report that silencing of SENP2 and consequent activation of NF-κB through the modulation of IκBα sumoylation as a novel mechanism inducing bortezomib resistance in multiple myeloma.


Assuntos
Bortezomib/farmacologia , Cisteína Endopeptidases/genética , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Mieloma Múltiplo/genética , Inibidor de NF-kappaB alfa/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Simulação por Computador , Regulação Neoplásica da Expressão Gênica , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , NF-kappa B/metabolismo , RNA Guia de Cinetoplastídeos/farmacologia , Transdução de Sinais , Sumoilação
13.
Sci Rep ; 10(1): 498, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949170

RESUMO

The incidence of resistant Candida isolates, especially Candida albicans, has increased continuously. To overcome the resistance, research on antifungal agent sensitizers has attracted considerable attention. Omeprazole and lansoprazole were found to inhibit the growth of sensitive C. albicans and hyphae formation in a high dose, respectively. This study aimed to determine the interactions of common clinically proton pump inhibitors (PPIs) and fluconazole both in vitro and in vivo and to further explore the possible mechanisms. In vitro, the tested PPIs all acted synergistically with fluconazole against both resistant C. albicans planktonic cells and biofilms preformed for ≤12 h with the minimum inhibitory concentration of fluconazole decreased from >512 µg/mL to 1-4 µg/mL. In vivo, PPIs plus fluconazole prolonged the survival rate of infected Galleria mellonella larvae by two-fold compared with that for the fluconazole monotherapy group and significantly reduced the tissue damage of infected larvae. Mechanism studies showed that PPIs significantly suppressed efflux pump activity, which is the common resistance mechanism of C. albicans, and significantly inhibited the virulence factors: phospholipase activity and morphology switching. These findings will provide new insights into antifungal agent discovery and potential approaches for the treatment of candidiasis caused by resistant C. albicans.


Assuntos
Candida albicans/efeitos dos fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Fluconazol/farmacologia , Inibidores da Bomba de Prótons/farmacologia , Animais , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Candida albicans/crescimento & desenvolvimento , Sinergismo Farmacológico , Holometábolos/crescimento & desenvolvimento , Holometábolos/parasitologia , Hifas/efeitos dos fármacos , Testes de Sensibilidade Microbiana
14.
Int J Antimicrob Agents ; 55(1): 105804, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31605727

RESUMO

The incidence of fungal infections has increased continuously in recent years, and drug resistance, especially resistance to fluconazole (FLC), has emerged. To overcome this challenge, research on the antifungal activities of non-antifungal agents has gained more attention. In this study, we determined the anti-Candida activity of ribavirin (RBV), an antiviral drug commonly used in the clinic, and found that RBV displayed potent antifungal activity when used alone or in combination with FLC in vitro and in vivo. In vitro, the MIC80 values of RBV were 2-4 µg/mL for FLC-susceptible Candida albicans and 8 µg/mL for FLC-resistant C. albicans. When RBV at a dose of 1 µg/mL was combined with FLC, significant synergistic effects were exhibited against FLC-resistant C. albicans, and the MICs of FLC decreased from >512 µg/mL to 0.25-1 µg/mL. Synergism was also exhibited against C. albicans biofilms. In vivo, RBV plus FLC significantly improved the survival of infected Galleria mellonella larvae compared with the FLC-treated group over a 4-day period and attenuated the damage of FLC-resistant C. albicans to G. mellonella larvae tissue. Furthermore, mechanistic studies indicated that the antifungal effects of RBV used alone or in combination with FLC might be associated with inhibition of biofilm formation, reduced extracellular phospholipase activity and inhibition of hyphal growth, but is not related to promotion of FLC uptake and inhibition of FLC efflux. These results provide a promising direction for overcoming drug resistance and for expanding the clinical application of existing drugs.


Assuntos
Antifúngicos/administração & dosagem , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candidíase/tratamento farmacológico , Fluconazol/administração & dosagem , Ribavirina/administração & dosagem , Animais , Antifúngicos/farmacologia , Candida albicans/patogenicidade , Candidíase/microbiologia , Farmacorresistência Fúngica , Sinergismo Farmacológico , Fluconazol/farmacologia , Humanos , Larva , Mariposas , Ribavirina/farmacologia , Virulência
15.
Int J Antimicrob Agents ; 51(1): 107-114, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28943366

RESUMO

Candida spp. are the primary opportunistic pathogens of nosocomial fungal infections, causing both superficial and life-threatening systemic infections. Combination therapy for fungal infections has attracted considerable attention, especially for those caused by drug-resistant fungi. Gentamicin (GM), an aminoglycoside antibiotic, has weak antifungal activity against Fusarium spp. The aim of this study was to investigate the interactions of GM with azoles against Candida spp. and the underlying mechanisms. In a chequerboard assay, GM was found not only to work synergistically with azoles against planktonic cells of drug-resistant Candida albicans with a fractional inhibitory concentration index (FICI) of 0.13-0.14, but also synergised with fluconazole (FLC) against C. albicans biofilms pre-formed in <12 h. Synergism of GM with FLC was also confirmed in vivo in a Galleria mellonella infection model. In addition, mechanism studies showed that GM not only suppressed the efflux pump of resistant C. albicans in a dose-dependent manner but also inhibited extracellular phospholipase activity of resistant C. albicans when combined with FLC. These findings suggest that GM enhances the efficacy of azoles against resistant C. albicans via efflux inhibition and decreased activity of extracellular phospholipase.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Fluconazol/farmacologia , Gentamicinas/farmacologia , Mariposas/microbiologia , Animais , Infecção Hospitalar/microbiologia , Farmacorresistência Fúngica , Sinergismo Farmacológico , Humanos , Larva/microbiologia , Proteínas de Membrana Transportadoras/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Fosfolipases/antagonistas & inibidores
16.
Front Microbiol ; 9: 3142, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30766527

RESUMO

The incidence of resistant Candida isolates has increased continuously in recent decades, especially Candida albicans. To overcome this resistance, research on antifungal sensitizers has attracted considerable attention. Linezolid was found to inhibit the growth of Pythium insidiosum and synergize with amphotericin B against Cryptococcus neoformans. The objective of this study was to determine the interactions of linezolid and azoles against C. albicans in vitro and in vivo. In vitro, linezolid combined with azoles induced synergistic effects not only against some susceptible C. albicans isolates, but also against all tested resistant C. albicans isolates. For all resistant isolates, exposure to the combination of linezolid with azoles induced a significant decrease in the minimum inhibitory concentrations (MIC) of azoles, from >512 to 0.5-1 µg/mL for fluconazole, from >16 to 0.25-1 µg/mL for itraconazole, and from >16 to 0.03-0.25 µg/mL for voriconazole. Additionally, linezolid synergized with fluconazole against biofilms that were preformed for ≤ 12 h from both susceptible and resistant C. albicans, and the sessile MIC of fluconazole decreased from >1024 to 1-4 µg/mL. In vivo, linezolid plus azoles prolonged the survival rate of infected Galleria mellonella larvae twofold compared with the azole monotherapy group, significantly decreased the fungal burden of the infected larvae, and reduced the damage of resistant C. albicans to the larval tissue. These findings will contribute to antifungal agent discovery and new approaches for the treatment of candidiasis caused by C. albicans.

17.
Int J Antimicrob Agents ; 49(2): 125-136, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28040409

RESUMO

Invasive fungal infections caused by Candida spp. remain the most predominant nosocomial fungal infections. Owing to the increased use of antifungal agents, resistance of Candida spp. to antimycotics has emerged frequently, especially to fluconazole (FLC). To cope with this issue, new efforts have been dedicated to discovering novel antimycotics or new agents that can enhance the susceptibility of Candida spp. to existing antimycotics. The secondary metabolites of plants represent a large library of compounds that are important sources for new drugs or compounds suitable for further modification. Research on the anti-Candida activities of phytocompounds has been carried out in recent years and the results showed that a series of phytocompounds have anti-Candida properties, such as phenylpropanoids, flavonoids, terpenoids and alkaloids. Among these phytocompounds, some displayed potent antifungal activity, with minimum inhibitory concentrations (MICs) of ≤8 µg/mL, and several compounds were even more effective against drug-resistant Candida spp. than FLC or itraconazole (e.g. honokiol, magnolol and shikonin). Interestingly, quite a few phytocompounds not only displayed anti-Candida activity alone but also synergised with FLC against Candida spp., even leading to a reversal of FLC resistance. This review focuses on summarising the anti-Candida activities of phytocompounds as well as the interactions of phytocompounds with FLC. In addition, we briefly overview the synergistic mechanisms and present the structure of the antimycotic phytocompounds. Hopefully, this analysis will provide insight into antifungal agent discovery and new approaches against antifungal drug resistance.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Interações Medicamentosas , Fluconazol/farmacologia , Compostos Fitoquímicos/farmacologia , Testes de Sensibilidade Microbiana
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...