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1.
J Appl Microbiol ; 134(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37960923

RESUMO

AIMS: This study aimed to investigate the inhibitory effect of tannic acid (TA) on the growth of Apiospora arundinis and 3-Nitropropionic acid (3-NPA) production. METHODS AND RESULTS: To investigate the antifungal mechanism, the effects of TA on the hypha growth, electrical conductivity, hypha morphology, defense-related enzymes, and 3-NPA production of A. arundinis were studied. TA concentrations of 640 and 1280 µg ml-1 exhibited strong antifungal activity against A. arundinis. The results of scanning electron microscopy and transmission electron microscopy showed that the hypha of the A. arundinis was severely deformed after TA treatment, and the cell membrane was blurred and thin, vacuoles were obviously shrunken and smaller, and most of the organelles were decomposed into irregular fragments. The increased electrical conductivity and malondialdehyde content indicated that TA caused peroxidation of unsaturated fatty acids and damaged the structure of the cell membrane. The decrease of intracellular ATPase and succinate dehydrogenase content indicated that TA damaged the function of mitochondria, and participated in the inhibition of respiratory metabolism. In addition, TA significantly reduced 3-NPA production and completely inhibited 3-NPA production at 640 and 1280 µg ml-1. CONCLUSION: TA effectively inhibited both growth of A. arundinis in vitro and 3-NPA production.


Assuntos
Antifúngicos , Mitocôndrias , Antifúngicos/farmacologia , Propionatos/farmacologia
2.
Appl Opt ; 61(17): 5237-5243, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-36256206

RESUMO

A method of generating multiple solitons with controllable separation is proposed by injecting the dissipative soliton (DS) and conventional soliton (CS) into the polarization-maintaining fiber (PMF), respectively. The soliton separation can be adjusted subjectively from 12 to 28 ps, corresponding to PMF lengths from 10 to 24 m. Multiple solitons consisting of three, four, five, and six solitons can be observed at pump powers of 480, 550, 610, and 700 mW. DS's average single-pulse energy can increase from 20.4 to 40.7 pJ, while the average single-pulse energy of CS decreases from 29.3 to 13.7 pJ. The experimental results can contribute to the further understanding of the dynamics of multiple solitons.

4.
Comp Med ; 74(1): 19-24, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38365263

RESUMO

Among several existing mouse models for hepatitis B virus (HBV) infection, the high-pressure hydrodynamic injection (HDI) method is frequently used in HBV research due to its economic advantages and ease of implementation. The use of the HDI method is influenced by factors such as mouse genetic background, age, sex, and the type of HBV plasmid used. This overview provides a multidimensional analysis and comparison of various factors that influence the effectiveness of the HBV mouse model established through HDI. The goal is to provide a summary of information for researchers who create HBV models in mice.


Assuntos
Hepatite B , Doenças dos Roedores , Animais , Camundongos , Modelos Animais de Doenças , Vírus da Hepatite B/genética , Hidrodinâmica , Plasmídeos , Replicação Viral
5.
Front Microbiol ; 14: 1314887, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38188586

RESUMO

Sugarcane (Saccharum officinarum L.) may be infected with Apiospora, which can produce the toxin 3-nitropropionic acid (3-NPA) during improper transportation and storage. The consumption of sugarcane that contains 3-NPA can lead to food poisoning. Therefore, this study sought to explore a novel biocontrol agent to prevent and control Apiospora mold. Bacteria were isolated from the soil of healthy sugarcane and identified as Bacillus velezensis T9 through colony morphological, physiological and biochemical characterization and molecular identification. The inhibitory effect of B. velezensis T9 on Apiospora mold on sugarcane was analyzed. Assays of the cell suspension of strain T9 and its cell-free supernatant showed that T9 had significant in vitro antifungal activities against Apiospora arundinis and thus, would be a likely antagonist. Scanning electron microscopy and transmission electron microscopy showed that treatment with T9 significantly distorted the A. arundinis mycelia, perforated the membrane, contracted the vesicles, and decomposed most organelles into irregular fragments. A re-isolation experiment demonstrates the ability of T9 to colonize the sugarcane stems and survive in them. This strain can produce volatile organic compounds (VOCs) that are remarkably strong inhibitors, and it can also form biofilms. Additionally, the cell-free supernatant significantly reduced the ability of A. arundinis to produce 3-NPA and completely inhibited its production at 10%. Therefore, strain T9 is effective at controlling A. arundinis and has the potential for further development as a fungal prevention agent for agricultural products.

6.
J Ethnopharmacol ; 278: 114267, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34087401

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: As an important Chinese herb, Coptis chinensis Franch. (Huanglian, HL) has a long history of usage for clearing heat, eliminating dampness, purging fire and detoxification in Traditional Chinese Medicine (TCM). HL, also called goldthread, was frequently used for the treatment of typhoid, tuberculosis, epidemic cerebrospinal meningitis, pertussis, and other lung-related diseases. Modern research has shown that HL and its main compounds also have anti-tumor effects. However, studies have not reported whether its main compounds inhibit Non-small cell lung cancer (NSCLC) development and progression. OBJECTIVE: This study aimed to find out the potential targets and mechanisms of Oxyepiberberine (OPB) isolated from HL in the treatment of NSCLC, using network pharmacology and biological experimental. METHODS: Silica gel chromatography column was used to isolate OPB from HL, and the structure of OPB was elucidated using different spectroscopic analysis methods, including 1H-nuclear magnetic resonance (NMR), 13C-NMR and electrospray ionization mass spectrometry (ESI/MS). MTT assay was performed to determine cell proliferation of OPB on A549, H1975 and BEAS-2B cells. Then, the potential targets, pathways and hub genes of OPB for treating NSCLC were screened out through network pharmacology. Based on the results of network pharmacology, core targets of OPB for treating NSCLC were docking with OPB via molecular docking. Wound healing, plate clone, Hoechst staining, and western blot assay were used to verify the function of OPB in treatment of NSCLC. RESULTS: OPB was isolated from the HL, its molecular formula was identified as C20H17NO5. Through MTT, OPB significantly inhibited the proliferation of H1975 cells and A549 cells, and A549 was chosen as the test cancer cell. Through network pharmacology, 22 potential targets, 156 related-pathways, and 6 hub genes were screened out. The results of molecular docking showed that SRC, BRAF, and MMP9 were the core targets of OPB against NSCLC. Through biological experimental, it was found that OPB inhibited growth and migration of A549 cells. In addition, OPB induced apoptosis in A549 cells. Through western blot assay, the expressions of Src, ERK1/2 and other four proteins were down-regulated, which suggested that OPB inhibited the proliferation of lung cancer cells by down-regulating SRC-FAK-RAS-RAF-MEK-ERK pathway, so as to achieve the anti-NSCLC effect. CONCLUSION: Our study demonstrated that anti-NSCLC effect of OPB through network and experiments, which provided a theoretical basis for the clinical antitumor of OPB, and provided a foundation for further study of OPB.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Coptis chinensis/química , Neoplasias Pulmonares/tratamento farmacológico , Células A549 , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/patologia , Simulação de Acoplamento Molecular , Farmacologia em Rede
7.
Front Pharmacol ; 12: 586010, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025394

RESUMO

The flavonoid quercitrin has a strong antioxidant property. It is also reported to have a protective effect on the liver. However, the mechanism by which it exerts a protective effect on the liver is not fully understood. The objective of this article is to confirm the protective effect of quercitrin extracted from Albiziae flos on acetaminophen (APAP)-induced liver injury and to explain its mechanism. In the in vivo study, quercitrin was administered orally to BALB/c mice at a dose of 50, 100, and 200 mg/kg for seven consecutive days. APAP (300 mg/kg) was injected intraperitoneally after a last dose of quercitrin was administered. Determination of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), reactive oxygen species (ROS), superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GSH-Px), catalase (CAT), and malondialdehyde (MDA) levels showed that quercitrin effectively attenuated APAP-induced acute liver injury in mice. Results of the in vitro study showed that quercitrin reduced the levels of ROS, protected mitochondria from damage, and restored the activity of mitochondrial complex I in APAP-treated L-02 cells. The addition of rotenone which is an inhibitor of complex I blocked the protective effect of quercitrin. The expression of mitochondrial complex I was also maintained by quercitrin. Our results suggest that quercitrin can maintain the level of mitochondrial complex I in injured cells and restore its activity, which reduces the production of ROS, protects the mitochondria from oxidative stress, and has a protective effect on the liver.

8.
Int J Biol Macromol ; 183: 369-378, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33932413

RESUMO

Hydrophobic drugs loaded nanogels were always associated with low encapsulation efficiency and immature burst release. In this work, dopamine grafted hyaluronate nanogels were designed for bortezomib (BTZ), a hydrophobic anticancer drug and a proteasome inhibitor. It was found that there was a more efficient loading and pH-controlled release of BTZ due to the presence of dopamine groups on the skeleton of the nanogels. The drug loading content (DLC) were up to 8.58% as the nanogels modified with 29% dopamine, compared to the DLC of less than 1% for nanogels without dopamine modification. It was the pH-sensitive nature of the borated bonds between BTZ and catechol groups that endowed the pH-responsive release behavior of BTZ in vitro. In vitro study proved good biocompatibility and efficient cell uptake of the nanogels. In vivo anti-tumor experiments demonstrated that bortezomib loading into the nanogel significantly enhanced the therapeutic effect of the drug. After 14-day treatment, the average tumor volume of BTZ loaded nanogel group was reduced by 200% more than that of free BTZ group. Combined with CD44 receptor targeting ability of hyaluronate and the merits of nanogel, the catechol modified hyaluronate nanogel exhibited as an efficient chemotherapeutic formulation of BTZ for cancer treatment.


Assuntos
Antineoplásicos/química , Antineoplásicos/uso terapêutico , Bortezomib/química , Bortezomib/uso terapêutico , Dopamina/química , Nanogéis/química , Polietilenoglicóis/química , Polietilenoimina/química , Animais , Portadores de Fármacos/química , Humanos , Concentração de Íons de Hidrogênio
9.
ACS Omega ; 5(49): 32123-32130, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33344867

RESUMO

AIM OF STUDY: The main objective of this study was to investigate the antithrombotic and antiplatelet effect of the extract from Rostellularia procumbenss (L.) Nees and understand the mechanisms by which it exerts its antithrombotic and antiplatelet mechanisms. MATERIALS AND METHODS: The antithrombotic effective parts (RPE) were isolated using D101 macroporous adsorption resin and potential active ingredients (JAC) were isolated using the preparative liquid-phase method. The lactate dehydrogenase kit was used to determine the toxicity of RPE and JAC to platelets. The antiadhesion effect of RPE and JAC on platelets was observed by fluorescence microscopy with rhodamine phalloidin. Antithrombotic efficacy of RPE and JAC in vivo was evaluated by establishing a rat tail thrombosis model. Contents of p-selectin, TXB2, and 6-keto-PGF1α in rat serum were measured using an enzyme-linked immunosorbent (ELISA) assay, and the rat black tail rate was measured to prove the protective effect of RPE and JAC on the tail thrombus rat model. Western blot was used for detection of serum-related proteins in the tail thrombus rat model. RESULTS: The results showed that RPE had antithrombotic and antiplatelet effects. RPE and JAC have no toxicity to platelets. In vitro experiments showed that RPE and JAC had antiadhesion effects on platelets. In vivo experiments showed that RPE significantly inhibited the increase of p-selectin and TXB2 and significantly increased the content of 6-keto-PGF1α in the serum of rats. Western blot results demonstrated that RPE and JDB significantly inhibited the phosphorylation of the MAPK protein family in the platelets of rats, and RPE also significantly inhibited the phosphorylation of ß3 protein. CONCLUSIONS: RPE has antithrombotic and antiplatelet activity in vivo and vitro. Its mechanism may be via preventing integrin αIIbß3 activation, which in turn leads to the inhibition of the phosphorylation of the MAPK family and further suppresses TXA2, which leads to the antithrombotic and antiplatelet effects.

10.
Drug Deliv ; 27(1): 344-357, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32090637

RESUMO

Stimuli-responsive drug delivery systems (DDSs) are expected to realize site-specific drug release and kill cancer cells selectively. In this study, a pH-responsive micelle was designed utilizing the pH-sensitivity of borate bonds formed between dopamine and boronic acid. First, methyl (polyethylene glycol)-block-polycaprolactone (mPEG-PCL) was conjugated with 4-cyano-4-(thiobenzoylthio)pentanoic acid (CTP) to obtain a macroinitiator. Two different segments poly(dopamine methacrylamide) (PDMA) and poly(vinylphenylboronic acid) (PVBA) were then grafted to the end of mPEG-PCL. Two triblock copolymers, mPEG-PCL-PDMA and mPEG-PCL-PVBA, were then obtained by reversible addition-fragmentation transfer (RAFT) polymerization. These copolymers and their mixture self-assembled in aqueous solution to form micelles that were able to load hydrophobic anticancer drug doxorubicin (DOX). These two-component micelles were found to be pH-sensitive, in contrast to the one-component micelles. Furthermore, MTT studies showed that the micelles were almost nontoxic. The DOX-loaded micelles showed cytotoxicity equivalent to that of DOX at high concentration. In vivo antitumor experiments showed that this pH-sensitive polymeric micellar system had an enhanced therapeutic effect on tumors. These two-component boronate-based pH micelles are universally applicable to the delivery of anticancer drugs, showing great potential for cancer therapy.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Polímeros/química , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Ácidos Borônicos/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Micelas , Neoplasias/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Colloids Surf B Biointerfaces ; 95: 90-5, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22417405

RESUMO

Mesoporous silica (MS) and amino-functionalized mesoporous silica (NH(2)-FMS) were prepared and characterized using the techniques of transmission electron microscopy (TEM) and nitrogen adsorption-desorption. Voltammetry was used to investigate the electrochemical behavior of capsaicin at the amino-functionalized mesoporous silica, which was modified through carbon paste electrode (NH(2)-FMS/CPE). NH(2)-FMS/CPE showed better performance for the electrochemical oxidation of capsaicin, when compared with bare carbon paste electrode (CPE) and mesoporous silica modified carbon paste electrode (MS/CPE). We optimized the experimental conditions influencing the determination of capsaicin. Under optimal conditions, the oxidation peak current was proportional to capsaicin concentration in the range of 0.040-0.40 µmol L(-1)and 0.40-4.0 µmol L(-1), when the detection limit was 0.020 µmol L(-1) (S/N=3). The above method was successfully applied to determine capsaicin in hot pepper samples, yielding satisfactory results. The spiked recoveries were in the range of 93.1-100.7%.


Assuntos
Aminas/química , Capsaicina/análise , Carbono/química , Dióxido de Silício/química , Adsorção , Técnicas Eletroquímicas , Eletrodos , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Nitrogênio/química , Oxirredução , Tamanho da Partícula , Porosidade , Propriedades de Superfície
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