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1.
Talanta ; 238(Pt 1): 123032, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34857350

RESUMO

Herein, the split aptamers, chitosan oligosaccharide, and AuNPs were combined as nanocomposites that present different formations to develop a label-free colorimetric aptasensor for rapid detection of small molecules. Kanamycin was chosen as a model target. Computational studies were performed to assist in the design of orientated immobilization of the split aptamers onto the AuNPs surface. Chitosan oligosaccharide was initially applied as an aggregation inducer of AuNPs, and chitopentaose was screened as the optimal. Under optimized conditions, the proposed aptasensor showed high sensitivity and selectivity, with a limit of detection of 20.58 nM, a linear range of 25-800 nM, and good recoveries of 98.49-104.9% and 85.69-107.0% when employed to detect kanamycin in tap water and milk samples, respectively. Only 55 min was needed for the whole assay. More importantly, this study can serve as a novel and robust reference for the aptasensing detection of other small molecules.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Quitosana , Nanopartículas Metálicas , Nanocompostos , Colorimetria , Ouro , Canamicina , Limite de Detecção , Oligossacarídeos
2.
Anal Chim Acta ; 1187: 339169, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34753567

RESUMO

In this work, a multiply-amplified peroxidase-like colorimetric strategy was proposed for the high-specific recognition and ultrasensitive detection of kanamycin (Kana). Based on two Kana-aptamer triggered sequential reactions, G-quadruplex (G4) and DNA (hairpins) modified Ni-Fe layered double oxides (LDOs) could be obtained simultaneously. Later, a three-dimensional G4/LDO frame networks, as a novel DNAzyme, with enhanced peroxidase-like catalytic activity was assembled through electrostatic interaction. This DNAzyme catalyzed 3,3',5,5'-tetramethylbenzidine oxidation for the colorimetric detection of Kana. The enhancement principle was discussed and the charge transfer process during the catalytic reaction was investigated. Under the optimal experiment conditions, the proposed method exhibited high sensitivity, where the linear range is from 10 fM to 10 nM (r2 = 0.992), and the limit of detection is 3 fM (S/N = 3). The practicability of this assay was demonstrated by successfully application of residual Kana detection in genuine milk and urine samples.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , DNA Catalítico , Quadruplex G , Colorimetria , DNA Catalítico/metabolismo , Canamicina , Limite de Detecção , Óxidos
3.
Anal Chem ; 93(42): 14214-14222, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34644046

RESUMO

The abuse of antibiotics in modern life and aquaculture has become a worldwide problem. Trace amounts of antibiotics discharged into natural water are increased in organisms through bioaccumulation and ultimately harm human health. Herein, we report a metal-tagged CRISPR/Cas12a bioassay and apply it to an ultrasensitive and highly selective evaluation of antibiotics bioaccumulation in wild fish samples. We integrated an element-tagging report probe and collateral cleavage activity of CRISPR/Cas12a. With the recognition and capture of target kanamycin by a "locked-activated" system, the activator strand was subsequently released to activate the collateral cleavage activity of Cas12a, followed by the cleavage of free Tm-Rep. After SA-MB capture, the biotin terminal was modified, and the uncleaved probe of Tm-Rep was removed. The acidized supernate containing the element tag fragment could be directly detected with 169Tm isotope monitoring by inductively coupled plasma mass spectrometry (ICPMS). With CRISPR/Cas12a biosensing and metal isotope detection by ICPMS, ultrasensitive and fast antibiotics analysis was realized with multiplex detection potential. Taking kanamycin as a modal analyte, a limit of detection as low as 4.06 pM was provided in a 30 min detection workflow. Besides, the bioaccumulation effect of kanamycin in a wild fish sample was also evaluated using the proposed strategy. We investigated the geographical distribution with Pseudorasbora parva samples collected in four different locations along a 600 km stretch of the Yangtze River. In addition, the bioaccumulation kinetics of antibiotics was evaluated in serum, muscle, and liver tissues of Pseudorasbora parva with 7 days of continuous feeding in a kanamycin-enriched environment.


Assuntos
Técnicas Biossensoriais , Sistemas CRISPR-Cas , Bioacumulação , Bioensaio , Sistemas CRISPR-Cas/genética , Humanos , Canamicina
4.
Molecules ; 26(19)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34641512

RESUMO

The improper use of antibiotics has led to the development of bacterial resistance, resulting in fewer antibiotics for many bacterial infections. Especially, the drug resistance of hospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) is distinctly serious. This research designed and synthesized two series of 3-substituted ocotillol derivatives in order to improve their anti-HA-MRSA potency and synergistic antibacterial activity. Among the synthesized compounds, 20-31 showed minimum inhibitory concentration (MIC) values of 1-64 µg/mL in vitro against HA-MRSA 18-19, 18-20, and S. aureus ATCC29213. Compound 21 showed the best antibacterial activity, with an MIC of 1 µg/mL and had synergistic inhibitory effects. The fractional inhibitory concentration index (FICI) value was 0.375, when combined with chloramphenicol (CHL) or kanamycin (KAN). The structure-activity relationships (SARs) of ocotillol-type derivatives were also summarized. Compound 21 has the potential to be developed as a novel antibacterial agent or potentiator against HA-MRSA.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Ginsenosídeos/química , Cloranfenicol/farmacologia , Desenho de Fármacos , Sinergismo Farmacológico , Canamicina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
5.
Anal Chim Acta ; 1181: 338927, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34556232

RESUMO

A"signal-off" photoelectrochemical aptasensor based on p-n type semiconductor competitive quenching effect and strand displacement reaction was constructed for the determination of kanamycin. Au NPs@MgIn2S4-graphene composite was used as n-type photoactive semiconductor material. In the presence of the kanamycin, strand displacement reaction was triggered and the p-type CuInS2 quantum dots labeled aptamer was introduced on the Au NPs@MgIn2S4-graphene surface. The CuInS2 quantum dots can competitive consume the electron donors (AA) and light energy of the PEC system, thus quenched the anodic photocurrent of Au NPs@MgIn2S4-graphene. The photocurrent decreased with the increase of kanamycin concentration. The linear range of kanamycin was 1.0 pM-10 µM, and the detection limit was 1.7 pM. In addition, the method can be used for the determination of kanamycin in milk and honey.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Pontos Quânticos , Técnicas Eletroquímicas , Canamicina , Limite de Detecção
6.
Anal Chim Acta ; 1180: 338780, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34538325

RESUMO

Herein, a sensitive and selective electrochemiluminescence (ECL) aptasensor was designed using Au@HKUST-1 as accelerator towards the perylene derivative (PTC-Cys)/peroxydisulfate (S2O82-) system for kanamycin (KAN) assay. Firstly, the PTC-Cys was prepared by covalently binding l-cysteine to 3,4,9,10-perylenete-tracarboxylic acid, which was acted as the luminophore. Then Au@HKUST-1could play the part of effective catalyst to accelerate the electrochemical reduction process of S2O82-to produce more sulfate radical anions (SO4•-), thus the ECL signal of the compound was noticeably raised by 2.4 times in comparison with that in which only luminophore and S2O82- are present, achieving signal amplification of the ECL system. In the presence of KAN, aptamer was pulled down from the sensing interface, achieving a considerable enhancement of ECL intensity in S2O82- solution. Upon the optimal condition, our proposed strategy can quantify the concentration of KAN from 1.0 × 10-13 to 1.0 × 10-8 M with low limit of detection of 4.2 × 10-14 M (S/N = 3).Besides, our proposed ECL aptasensor exhibited excellent sensitivity, stability and specificity, and could be successfully applied to detect KAN in practical samples, which proved its potential to detect other antibiotics in food security.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Cisteína , Técnicas Eletroquímicas , Canamicina , Limite de Detecção , Medições Luminescentes , Estruturas Metalorgânicas
7.
Antimicrob Agents Chemother ; 65(11): e0116421, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34460306

RESUMO

Antibiotic resistance among bacterial pathogens poses a major global health threat. Mycobacterium tuberculosis complex (MTBC) is estimated to have the highest resistance rates of any pathogen globally. Given the low growth rate and the need for a biosafety level 3 laboratory, the only realistic avenue to scale up drug susceptibility testing (DST) for this pathogen is to rely on genotypic techniques. This raises the fundamental question of whether a mutation is a reliable surrogate for phenotypic resistance or whether the presence of a second mutation can completely counteract its effect, resulting in major diagnostic errors (i.e., systematic false resistance results). To date, such epistatic interactions have only been reported for streptomycin that is now rarely used. By analyzing more than 31,000 MTBC genomes, we demonstrated that the eis C-14T promoter mutation, which is interrogated by several genotypic DST assays endorsed by the World Health Organization, cannot confer resistance to amikacin and kanamycin if it coincides with loss-of-function (LoF) mutations in the coding region of eis. To our knowledge, this represents the first definitive example of antibiotic reversion in MTBC. Moreover, we raise the possibility that mmpR (Rv0678) mutations are not valid markers of resistance to bedaquiline and clofazimine if these coincide with an LoF mutation in the efflux pump encoded by mmpS5 (Rv0677c) and mmpL5 (Rv0676c).


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Amicacina/farmacologia , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Clofazimina/farmacologia , Diarilquinolinas , Farmacorresistência Bacteriana Múltipla/genética , Epistasia Genética , Humanos , Canamicina/farmacologia , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/genética
8.
J Agric Food Chem ; 69(35): 10371-10378, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34436884

RESUMO

Herein, we combine the exonuclease III (Exo III)-catalyzed release of a Zn2+-dependent ligation DNAzyme with the DNAzyme-driven strand displacement reaction (SDR) to develop a novel homogeneous colorimetric bioassay method for kanamycin (Kana) antibiotic detection. Upon the biorecognition reaction between Kana and a designed hairpin DNA, the DNAzyme-containing strand can be catalytically released by Exo III. Then, this DNAzyme will catalyze the ligation of two oligonucleotides to cause a SDR and the aggregation of gold nanoparticles (Au NPs) labeled by two linker DNA strands. Due to the aggregation of Au NPs for colorimetric signal transduction and the Exo III and SDR-assisted dual signal amplification, this method shows a wide linear range of 5 orders of magnitude and a very low detection limit down to 8.1 fg mL-1. Together with its excellent selectivity, repeatability, reliability, and convenient manipulation, the proposed method shows a great potential for the food quality monitoring application.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , DNA Catalítico , Nanopartículas Metálicas , Antibacterianos , Bioensaio , Catálise , Exodesoxirribonucleases , Ouro , Canamicina , Limite de Detecção , Reprodutibilidade dos Testes , Zinco
9.
J Hazard Mater ; 420: 126601, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34265652

RESUMO

There is an increase in demand to develop simple, convenient, and low-cost approaches for rapid and label-free detection of antibiotics. Herein, we propose a new principle for the detection of kanamycin using the surface-anchored liquid crystal (LC) droplets. The optical images of the LC droplets uniformly change from four-clover, uniformly dark, and dark cross appearance gradually with the increase of surfactant concentration. The detection of kanamycin is fulfilled with the aid of a cationic surfactant cetyltrimethylammonium bromide (CTAB) and a kanamycin aptamer. The LC droplets show uniformly dark appearance and four-clover appearance in the presence of the aqueous solutions of CTAB and CTAB/aptamer complex, respectively. However, the specific binding of kanamycin to its aptamer can release the CTAB, which induces the uniformly dark appearance of the LC droplets. A portable device is built to measure the optical luminance of the LC droplets. This system can detect kanamycin with a concentration below 0.1 ng/mL (~0.17 nM) and also allows the detection of kanamycin in real samples such as milk and honey. Therefore, it is very promising in the development of new types of LC-based sensors by the surface-anchored LC droplets assisted with a portable optical device.


Assuntos
Cristais Líquidos , Animais , Antibacterianos , Canamicina , Leite , Tensoativos
10.
Biomacromolecules ; 22(8): 3534-3542, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34251178

RESUMO

Typically, quaternary ammonium polymers are employed for antibacterial purposes. However, a century of use has led bacteria to develop resistance to such materials. Therefore, attention is now turning toward other cationic moieties. In this context, the present work explores sulfur-based main-chain cationic polymers. The results indicate that sulfonium polymers with a ß-hydroxy motif do not suffer from structural instability issues as is commonly observed in cationic polythioethers. Furthermore, they can be highly effective toward important Gram-positive bacterial strains such as Mycobacterium smegmatis, a model organism to develop drugs against rapidly spreading tuberculosis infections. More importantly, however, more challenging Gram-negative strains such as Escherichia coli can also be targeted by the polysulfoniums with equal effectiveness. Interestingly, side-chain sulfonium polyelectrolytes are observed to be devoid of any significant antibacterial activity. Finally, a comparison with kanamycin and vancomycin suggests the present polymers to be similarly effective as the bactericidal antibiotic drugs. Overall, these results indicate the effectiveness of the main-chain trivalent ß-hydroxy sulfonium motif for the development of novel antibacterial polymers with a non-ammonium structure.


Assuntos
Compostos de Amônio , Preparações Farmacêuticas , Antibacterianos/farmacologia , Canamicina , Testes de Sensibilidade Microbiana , Polímeros , Sais , Vancomicina
11.
Antimicrob Agents Chemother ; 65(10): e0050621, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34252307

RESUMO

Amikacin and kanamycin are second-line injectables used in the treatment of multidrug-resistant tuberculosis (MDR-TB) based on the clinical utility of streptomycin, another aminoglycoside and first-line anti-TB drug. While streptomycin was tested as a single agent in the first controlled TB clinical trial, introduction of amikacin and kanamycin into MDR-TB regimens was not preceded by randomized controlled trials. A recent large retrospective meta-analysis revealed that compared with regimens without any injectable drug, amikacin provided modest benefits, and kanamycin was associated with worse outcomes. Although their long-term use can cause irreversible ototoxicity, they remain part of MDR-TB regimens because they have a role in preventing emergence of resistance to other drugs. To quantify the contribution of amikacin and kanamycin to second-line regimens, we applied two-dimensional matrix-assisted laser desorption ionization (MALDI) mass spectrometry imaging in large lung lesions, quantified drug exposure in lung and in lesions of rabbits with active TB, and measured the concentrations required to kill or inhibit growth of the resident bacterial populations. Using these metrics, we applied site-of-action pharmacokinetic and pharmacodynamic (PK-PD) concepts and simulated drug coverage in patients' lung lesions. The results provide a pharmacological explanation for the limited clinical utility of both agents and reveal better PK-PD lesion coverage for amikacin than kanamycin, consistent with retrospective data of contribution to treatment success. Together with recent mechanistic studies dissecting antibacterial activity from aminoglycoside ototoxicity, the limited but rapid penetration of streptomycin, amikacin, and kanamycin to the sites of TB disease supports the development of analogs with improved efficacy and tolerability.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose Pulmonar , Animais , Antituberculosos/uso terapêutico , Humanos , Canamicina , Coelhos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/tratamento farmacológico
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 262: 120147, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34271239

RESUMO

Kanamycin (KAN) is widely used in animal husbandry to treat bacterial infections. However, excessive KAN may cause residues and be transmitted to humans and the environment, causing serious adverse effects on humans. Herein, a simple fluorescence resonance energy transfer (FRET)-based aptasensor has been developed for sensitive detection of KAN in food. In the absence of KAN, UCNPs-aptamer hybridized with BHQ3-cDNA and quenched fluorescence was observed due to the FRET effect between BHQ3 and UCNPs. In the presence of KAN, double strands separated and the fluorescence intensity was recovered. Additionally, a linear relation (R2 = 0.9926) was found in the range of 0.05-50 µM and the recovered fluorescence intensity at 654 nm with a detection limit of 18.9 nM. The method was verified by standard recovery method and HPLC with satisfactory recovery rate (87.0-109.6%) and accuracy (P > 0.05). These results showed the proposed method could be successfully applied to detect KAN in food samples.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Animais , Transferência Ressonante de Energia de Fluorescência , Alimentos , Humanos , Canamicina , Limite de Detecção
13.
Molecules ; 26(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206584

RESUMO

In this work, a simple and rapid method based on the lateral flow assay (LFA) has been developed for the detection of dual antibiotics. To achieve the quantitative assay and to reduce the non-specific adsorption, an internal system has been developed. A non-specific DNA was exploited as an internal standard and could be recognized by the DNA marker that was coated at the internal line. Two different kinds of aptamers were applied to recognize ampicillin (AMP) and kanamycin (KAM), and the distance between the detection line and conjugate pad was then optimized. Under the optimum conditions, the quantitative assays of AMP (R2 = 0.984) and KAM (R2 = 0.990) were achieved with dynamic ranges of 0.50 to 500.0 ng/L, and of 0.50 to 1000.0 ng/L, respectively. The LOQs of AMP and KAM were 0.06 ng/L and 0.015 ng/L, respectively. Finally, the proposed method has been successfully applied to analyze aquaculture water, tap water, and lake water, and hospital wastewater, indicating the established method could be used to monitor the environment.


Assuntos
Ampicilina/análise , Aptâmeros de Nucleotídeos/química , Canamicina/análise , Água/análise
14.
Anal Chim Acta ; 1169: 338631, 2021 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-34088369

RESUMO

A biosensor in which an affinity reaction occurs in the sensitive microzone through the use of specific aptamers to determine kanamycin residues in agri-food samples has been developed. It is an irreversible and continuous flow aptameric biosensor (aptasensor) in which the signal variations are monitored by surface plasmon resonance (SPR) measurements based on the specific interaction of the aptamer with the antibiotic. The signal variation is proportional to the analyte concentration. Graphene is known for efficient binding of molecules with its π-electron system, so a monolayer of graphene prepared from chemical vapor deposition (CVD) has been compared to a multilayer of graphene made from reduced graphene oxide (rGO) for immobilization of the aptamer on the gold surface of the physicochemical transducer. The best results have been obtained with CVD graphene. The dynamic range was between 1 and 100 µmol L-1 of kanamycin concentration (r2 = 0.9981, n = 7, r = 4), with a limit of detection of 285 nmol L-1 and a sampling frequency of 6 h-1. The precision, expressed as relative standard deviation (RSD%), was established in the range of 1.49 and 3.89%, calculated for 1, 10, and 50 µmol L-1. The selectivity was studied applying the described method to determine other antibiotics, obtaining no significant difference in the analytical signal. The method was applied to determine kanamycin residues in milk samples with recovery values ranging between 90 and 96%.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Grafite , Canamicina , Limite de Detecção , Ressonância de Plasmônio de Superfície
15.
RNA ; 27(9): 981-990, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34117118

RESUMO

Many antibiotics that bind to the ribosome inhibit translation by blocking the movement of tRNAs and mRNA or interfering with ribosome dynamics, which impairs the formation of essential translocation intermediates. Here we show how translocation inhibitors viomycin (Vio), neomycin (Neo), paromomycin (Par), kanamycin (Kan), spectinomycin (Spc), hygromycin B (HygB), and streptomycin (Str, an antibiotic that does not inhibit tRNA movement), affect principal motions of the small ribosomal subunits (SSU) during EF-G-promoted translocation. Using ensemble kinetics, we studied the SSU body domain rotation and SSU head domain swiveling in real time. We show that although antibiotics binding to the ribosome can favor a particular ribosome conformation in the absence of EF-G, their kinetic effect on the EF-G-induced transition to the rotated/swiveled state of the SSU is moderate. The antibiotics mostly inhibit backward movements of the SSU body and/or the head domains. Vio, Spc, and high concentrations of Neo completely inhibit the backward movements of the SSU body and head domain. Kan, Par, HygB, and low concentrations of Neo slow down both movements, but their sequence and coordination are retained. Finally, Str has very little effect on the backward rotation of the SSU body domain, but retards the SSU head movement. The data underscore the importance of ribosome dynamics for tRNA-mRNA translocation and provide new insights into the mechanism of antibiotic action.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , RNA Mensageiro/metabolismo , RNA de Transferência/metabolismo , Subunidades Ribossômicas/efeitos dos fármacos , Transporte Biológico , Cinamatos/farmacologia , Escherichia coli/genética , Escherichia coli/metabolismo , Higromicina B/análogos & derivados , Higromicina B/farmacologia , Canamicina/farmacologia , Cinética , Neomicina/farmacologia , Paromomicina/farmacologia , Fator G para Elongação de Peptídeos/genética , Fator G para Elongação de Peptídeos/metabolismo , RNA Mensageiro/química , RNA Mensageiro/genética , RNA de Transferência/antagonistas & inibidores , RNA de Transferência/química , RNA de Transferência/genética , Subunidades Ribossômicas/genética , Subunidades Ribossômicas/metabolismo , Subunidades Ribossômicas/ultraestrutura , Espectinomicina/farmacologia , Estreptomicina/farmacologia , Viomicina/farmacologia
16.
Food Chem ; 362: 130261, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34111691

RESUMO

In this study, a novel surface enhanced Raman spectroscopy (SERS) sensor was developed for the ultrasensitive determination of kanamycin in foods. The sensor used two distinct signal amplification strategies, namely the surface plasmon resonance of gold nanorods and a Zn-doped carbon quantum dots catalytic cascade oxidation-reduction reaction switch controlled by a nucleic acid aptamer. Under optimized experimental conditions, the SERS sensor demonstrated a linear range of 10-12 to 10-5 g mL-1 for the detection of kanamycin, with a limit of detection of 3.03 × 10-13 g mL-1. Experiments with antibiotics structurally similar to kanamycin and interferrants revealed that the sensor had excellent selectivity. Milkpowder and honey samples spiked with kanamycin were assayed, with recoveries ranging from 84.1% to 107.2% and a relative standard deviation of 0.74% to 2.81% being obtained. Quantification of kanamycin in milk samples revealed no significant difference between the results obtained with the sensor and by HPLC.


Assuntos
Aptâmeros de Nucleotídeos/química , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Canamicina/análise , Nanotubos/química , Pontos Quânticos/química , Zinco/química , Antibacterianos/análise , Técnicas Biossensoriais/instrumentação , Carbono/química , Catálise , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Ressonância de Plasmônio de Superfície
17.
Int J Mol Sci ; 22(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34070066

RESUMO

Megalin has been proposed as an endocytic receptor for aminoglycosides as well as estrogen and androgen. We aimed to investigate the otoprotective effects of antiandrogens (flutamide, FM) on kanamycin (KM)-induced hearing loss in rats. Rats were divided into four groups. The KM group was administered KM (20 mg/kg/day) for 5 days, while the FM group received FM (15 mg/kg/day) for 10 days. In the KM + FM group, KM and FM (15 mg/kg/day) were simultaneously injected for 5 days and then FM was injected for 5 days. Auditory brainstem responses were measured. Western blotting and/or quantitative reverse transcriptase-polymerase chain reaction were performed for megalin, cytochrome P450 1A1 (Cyp1a1), Cyp1b1, metallothionein 1A (MT1A), MT2A, tumor necrosis factor (TNF)-α, caspase 3, and cleaved caspase 3. The FM + KM group showed attenuated auditory thresholds when compared with the KM group at 4, 8, 16, and 32 kHz (all p < 0.05). The KM + FM group showed lower megalin and Cyp1b1 levels than the KM group (all p < 0.05). The KM + FM group revealed lower MT1A, TNFα, and caspase 3 protein levels, compared with those in the KM group (all p < 0.05). Androgen receptor inhibition protects against cochlear injuries in KM-induced hearing loss rats by attenuating megalin expression, revealing anti-inflammatory and anti-apoptotic effects.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Perda Auditiva Neurossensorial/prevenção & controle , Animais , Antibacterianos/toxicidade , Limiar Auditivo/efeitos dos fármacos , Cóclea/efeitos dos fármacos , Cóclea/patologia , Cóclea/fisiopatologia , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/metabolismo , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Flutamida/farmacologia , Expressão Gênica/efeitos dos fármacos , Perda Auditiva Neurossensorial/induzido quimicamente , Perda Auditiva Neurossensorial/fisiopatologia , Canamicina/toxicidade , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Masculino , Metalotioneína/genética , Metalotioneína/metabolismo , Substâncias Protetoras/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
18.
Appl Environ Microbiol ; 87(15): e0046821, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34020940

RESUMO

The common cooccurrence of antibiotics and phages in both natural and engineered environments underscores the need to understand their interactions and implications for bacterial control and antibiotic resistance propagation. Here, aminoglycoside antibiotics that inhibit protein synthesis (e.g., kanamycin and neomycin) impeded the replication of coliphage T3 and Bacillus phage BSP, reducing their infection efficiency and mitigating their hindrance of bacterial growth, biofilm formation, and tolerance to antibiotics. For example, treatment with phage T3 reduced subsequent biofilm formation by Escherichia coli liquid cultures to 53% ± 5% of that of the no-phage control, but a smaller reduction of biofilm formation (89% ± 10%) was observed for combined exposure to phage T3 and kanamycin. Despite sharing a similar mode of action with aminoglycosides (i.e., inhibiting protein synthesis) and antagonizing phage replication, albeit to a lesser degree, tetracyclines did not inhibit bacterial control by phages. Phage T3 combined with tetracycline showed higher suppression of biofilm formation than when combined with aminoglycosides (25% ± 6% of the no-phage control). The addition of phage T3 to E. coli suspensions with tetracycline also suppressed the development of tolerance to tetracycline. However, this suppression of antibiotic tolerance development disappeared when tetracycline was replaced with 3 mg/liter kanamycin, corroborating the greater antagonism with aminoglycosides. Overall, this study highlights this overlooked antagonistic effect on phage proliferation, which may attenuate phage suppression of bacterial growth, biofilm formation, antibiotic tolerance, and maintenance of antibiotic resistance genes. IMPORTANCE The coexistence of residual antibiotics and phages is common in many environments, which underscores the need to understand their interactive effects on bacteria and the implications for antibiotic resistance propagation. Here, aminoglycosides acting as bacterial protein synthesis inhibitors impeded the replication of various phages. This alleviated the suppressive effects of phages against bacterial growth and biofilm formation and diminished bacterial fitness costs that suppress the emergence of tolerance to antibiotics. We show that changes in bacteria caused by environmentally relevant concentrations of sublethal antibiotics can affect phage-host dynamics that are commonly overlooked in vitro but can result in unexpected environmental consequences.


Assuntos
Antibacterianos/farmacologia , Fagos Bacilares/efeitos dos fármacos , Bacillus cereus/efeitos dos fármacos , Bacteriófago T3/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Canamicina/farmacologia , Neomicina/farmacologia , Fagos Bacilares/crescimento & desenvolvimento , Bacillus cereus/fisiologia , Bacillus cereus/virologia , Bacteriófago T3/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Escherichia coli/fisiologia , Escherichia coli/virologia , Tetraciclina/farmacologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-34006198

RESUMO

Aptamers, as single-stranded DNA or RNA fragments, have been widely applied as the bio-recognition element for fabrication of flexible and reliable aptasensors to be used in food safety control, clinical therapy and diagnosis and environment monitoring fields. With increasingly fierce antibiotics resistance appearing as a worldwide problem, a highly efficient method is urgently needed to detect antibiotics residues in animal-sourced food. Herein, a simply operated aptasensor based on quantitative real-time PCR (qRT-PCR) was fabricated to realise the simultaneous detection of two antibiotics (i.e. chloramphenicol and kanamycin). The limit of detection (LOD) of 6.13 ng/mL for chloramphenicol and of 19.17 ng/mL for kanamycin of this dual-aptasensor were achieved. Actually, such LOD values were not as good as that of an aptasensor individually established for each antibiotic. The circular dichroism analysis suggested that in the dual-aptasensor, adjacent aptamers might disturb each other's binding with their respective target. Although certain detection sensitivity was lost, the dual-aptasensor could still fulfil the detection requirements, and more importantly, it would improve the detection efficiency. Finally, this dual-aptasensor was applied for detecting chloramphenicol and kanamycin in real spiked food samples, and results indicated good recovery rates. These results demonstrated this developed dual-aptasensor to be a promising highly efficient method with low cost for simultaneous detection of chloramphenicol and kanamycin residues in animal-sourced food samples.


Assuntos
Antibacterianos/análise , Aptâmeros de Nucleotídeos/química , Cloranfenicol/análise , Canamicina/análise , Aptâmeros de Nucleotídeos/genética
20.
Antimicrob Agents Chemother ; 65(7): e0250220, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33903113

RESUMO

Eis promoter mutations can confer reduced Mycobacterium tuberculosis kanamycin susceptibility. GenoType MTBDRsl, a widely used assay evaluating this region, wrongly classified 17/410 isolates as eis promoter wild type. Six out of seventeen isolates harbored mutations known to confer kanamycin resistance, and the remainder harbored either novel eis promoter mutations (7/11) or disputed mutations (4/11). GenoType MTBDRsl can miss established and new variants that cause reduced susceptibility. These data highlight the importance of reflex phenotypic kanamycin testing.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Testes Diagnósticos de Rotina , Farmacorresistência Bacteriana Múltipla , Genótipo , Humanos , Canamicina/farmacologia , Resistência a Canamicina/genética , Testes de Sensibilidade Microbiana , Mutação/genética , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/genética
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