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1.
J Med Microbiol ; 73(7)2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38973691

RESUMO

Introduction. Aminoglycoside antibiotics such as amikacin and kanamycin are important components in the treatment of Mycobacterium tuberculosis (Mtb) infection. However, more and more clinical strains are found to be aminoglycoside antibiotic-resistant. Apramycin is another kind of aminoglycoside antibiotic that is commonly used to treat infections in animals.Hypothesis. Apramycin may have in vitro activity against Mtb.Aim. This study aims to evaluate the efficacy of apramycin against Mtb in vitro and determine its epidemiological cut-off (ECOFF) value.Methodology. One hundred Mtb isolates, including 17 pansusceptible and 83 drug-resistant tuberculosis (DR-TB) strains, were analysed for apramycin resistance using the MIC assay.Results. Apramycin exhibited significant inhibitory activity against Mtb clinical isolates, with an MIC50 of 0.5 µg ml-1 and an MIC90 of 1 µg ml-1. We determined the tentative ECOFF value as 1 µg ml-1 for apramycin. The resistant rates of multidrug-resistant tuberculosis (MDR-TB), pre-extensively drug-resistant (pre-XDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) strains were 12.12 % (4/33), 20.69 % (6/29) and 66.67 % (14/21), respectively. The rrs gene A1401G is associated with apramycin resistance, as well as the cross-resistance between apramycin and other aminoglycosides.Conclusion. Apramycin shows high in vitro activity against the Mtb clinical isolates, especially the MDR-TB clinical isolates. This encouraging discovery calls for more research on the functions of apramycin in vivo and as a possible antibiotic for the treatment of drug-resistant TB.


Assuntos
Antituberculosos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis , Nebramicina , Nebramicina/análogos & derivados , Nebramicina/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Humanos , Antituberculosos/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Farmacorresistência Bacteriana Múltipla
2.
Eur J Immunol ; : e2350796, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38922884

RESUMO

Tuberculosis (TB) was the leading cause of death from a single infectious agent before the coronavirus pandemic. Therefore, it is important to search for severity biomarkers and devise appropriate therapies. A total of 139 pulmonary TB (PTB) patients and 80 healthy controls (HCs) were recruited for plasma soluble CD137 (sCD137) detection through ELISA. Moreover, pleural effusion sCD137 levels were measured in 85 TB patients and 36 untreated lung cancer patients. The plasma cytokine levels in 64 patients with PTB and blood immune cell subpopulations in 68 patients with PTB were analysed via flow cytometry. Blood sCD137 levels were higher in PTB patients (p = 0.012) and correlated with disease severity (p = 0.0056). The level of sCD137 in tuberculous pleurisy effusion (TPE) was markedly higher than that in malignant pleurisy effusion (p = 0.018). Several blood cytokines, such as IL-6 (p = 0.0147), IL-8 (p = 0.0477), IP-10 (p ≤ 0.0001) and MCP-1 (p = 0.0057), and some laboratory indices were significantly elevated in severe PTB (SE) patients, but the percentages of total lymphocytes (p = 0.002) and cytotoxic T cells (p = 0.036) were significantly lower in SE patients than in non-SE patients. In addition, the sCD137 level was negatively correlated with the percentage of total lymphocytes (p = 0.0008) and cytotoxic T cells (p = 0.0021), and PTB patients with higher plasma sCD137 levels had significantly shorter survival times (p = 0.0041). An increase in sCD137 is a potential biomarker for severe TB and indicates a poor prognosis.

3.
Micromachines (Basel) ; 15(6)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38930742

RESUMO

This paper presents a comprehensive study on single- and repetitive-frequency UIS characteristics of 1200 V asymmetric (AT) and double trench silicon carbide (DT-SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) and their electrical degradation under electrical-thermal working conditions, investigated through experiment and simulation verification. Because their structure is different, the failure mechanisms are different. Comparatively, the gate oxide of a DT-MOSFET is more easily damaged than an AT-MOSFET because the hot carriers are injected into the oxide. The parameters' degradation under repetitive UIS stress also requires analysis. The variations in the measured parameters are recorded to evaluate typical electrical features of device failure. Furthermore, TCAD simulation is used to reveal the electrothermal stress inside the device during avalanche. Additionally, failed devices are decapsulated to verify the location of the failure point. Finally, a new type of stepped-oxide vertical power DT MOSFET with P-type shielding and current spread layers, along with its feasible process flow, is proposed for the improvement of gate dielectric reliability.

4.
J Food Sci ; 89(7): 4480-4492, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38847765

RESUMO

Depression is a prevalent psychiatric disease with the characteristic of persistently gloomy mood. The treatment of depression with traditional therapeutic medications suffers from low efficacy and adverse side effects due to the extremely unpredictable courses and uneven responses to treatment. The goal of this paper was to investigate the preparation of selenium-enriched fermented goat milk and the potential mechanism of its intervention on the chronic unpredictable stress-induced depression mice model. The results showed that Se-Lactobacillus paracasei 20241 (Se-20241) significantly alleviated depressive behavior, reversed the upregulation of inflammatory factors, and attenuated glucocorticoid resistance. Meanwhile, the results showed a modulatory function on oxidative stress dysfunction in the liver, hippocampus, and prefrontal cortex. The change in abundance of Ileibacterium, Muribaculaceae, Turicibacter, Dubosiella, and Bifidobacterium was also modified. These results provided the theoretical groundwork for the development of psychoactive probiotic supplements for depressed patients and clarified the probable mechanism of Se-20241 for antidepressant impact on the CUMS model.


Assuntos
Depressão , Modelos Animais de Doenças , Cabras , Lacticaseibacillus paracasei , Leite , Probióticos , Selênio , Animais , Selênio/farmacologia , Depressão/terapia , Camundongos , Probióticos/farmacologia , Masculino , Lacticaseibacillus paracasei/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Produtos Fermentados do Leite/microbiologia , Fermentação , Antidepressivos/farmacologia , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Estresse Psicológico , Comportamento Animal/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos
5.
Food Funct ; 15(14): 7619-7630, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38940701

RESUMO

Copper II oxide nanoparticles (CuO NPs), a kind of widely used nanomaterial, have been detected in food and the environment, which has aroused widespread public concern. Recently, increasing data have suggested that intestinal microecology is closely related to immune homeostasis. However, the intestinal immunotoxicity induced by CuO NPs through intestinal microbiota is still unknown. Therefore, in this study, zebrafish were exposed to CuO NPs to explore intestinal immunotoxicity by evaluating physiological indicators, intestinal tissue injury, antioxidant enzyme activities, gene expression of immune factors, and changes in intestinal microbiota and its metabolites (short-chain fatty acids (SCFAs) and lipopolysaccharides (LPS)). The results revealed that the intestinal immunotoxicity of CuO NPs was mediated by the impact on intestinal microbiota and its metabolite levels. Specifically, changes were observed in the abundance of microbes that participated in the metabolism of SCFAs and LPS. The reduction in acetic acid, propionic acid and valeric acid upregulated GPR84 expression, and the decline in LPS levels further resulted in the suppression of the key immune regulatory pathways TLR4/MyD88/NF-κB, ultimately leading to intestinal immunotoxicity. This study would provide a scientific basis for the risk assessment of CuO NPs and a new perspective for research on the immunotoxicity of nanoparticles.


Assuntos
Cobre , Disbiose , Ácidos Graxos Voláteis , Microbioma Gastrointestinal , Peixe-Zebra , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Disbiose/induzido quimicamente , Disbiose/microbiologia , Cobre/toxicidade , Ácidos Graxos Voláteis/metabolismo , Nanopartículas Metálicas/toxicidade , Intestinos/efeitos dos fármacos , Intestinos/imunologia , Intestinos/microbiologia , Nanopartículas/toxicidade , Lipopolissacarídeos
6.
J Chromatogr A ; 1727: 464988, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38749348

RESUMO

In this research, a novel magnetic nanocomposite (Fe3O4@Zn/Al-LABSA-LDH/ZIF-8) was synthesized using Fe3O4 as the magnetic core, layered double hydroxide (LDH) with linear alkylbenzene sulfonic acid (LABSA) intercalation and zeolitic imidazolate framework-8 (ZIF-8) as the shell. Benefiting from the intercalation of LABSA into LDH combined with ZIF-8, the multiple interactions, including π-π stacking, hydrogen bonding, and electrostatic interactions, conferred high selectivity and good extraction capability to the material towards heterocyclic aromatic amines (HAAs). Fe3O4@Zn/Al-LABSA-LDH@ZIF-8 was used as an adsorbent for magnetic solid-phase extraction (MSPE) to enrich HAAs in thermally processed meat samples, followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) detection. The method exhibited a low detection limit (0.021-0.221 ng/g), good linearity (R2 ≥ 0.9999), high precision (RSD < 7.2 %), and satisfactory sample recovery (89.7 % -107.5 %). This research provides a promising approach for developing novel adsorbents in sample preparation and improving analytical performance.


Assuntos
Aminas , Limite de Detecção , Nanocompostos , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Aminas/análise , Aminas/química , Nanocompostos/química , Extração em Fase Sólida/métodos , Imidazóis/química , Compostos Heterocíclicos/análise , Compostos Heterocíclicos/química , Hidróxidos/química , Zeolitas/química , Carne/análise , Estruturas Metalorgânicas/química , Adsorção , Contaminação de Alimentos/análise , Espectrometria de Massa com Cromatografia Líquida
7.
Food Microbiol ; 120: 104475, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38431321

RESUMO

Alicyclobacillus acidoterrestris is the major threat to fruit juice for its off-odor producing characteristic. In this study, Pyrococcus furiosus Argonaute (PfAgo), a novel endonuclease with precise DNA cleavage activity, was used for A. acidoterrestrisdetection, termed as PAD. The partially amplified 16 S rRNA gene of A. acidoterrestris can be cleaved by PfAgo activated by a short 5'-phosphorylated single strand DNA, producing a new guide DNA (gDNA). Then, PfAgo was activated by the new gDNA to cut a molecular beacon (MB) with fluorophore-quencher reporter, resulting in the recovery of fluorescence. The fluorescent intensity is positively related with the concentration of A. acidoterrestris. The PAD assay showed excellent specificity and sensitivity as low as 101 CFU/mL, which can be a powerful tool for on-site detection of A. acidoterrestris in fruit juice industry in the future, reducing the economic loss.


Assuntos
Alicyclobacillus , Pyrococcus furiosus , Sucos de Frutas e Vegetais , Pyrococcus furiosus/genética , Alicyclobacillus/genética , DNA , Frutas
8.
J Agric Food Chem ; 72(2): 1354-1360, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38174972

RESUMO

Pyrococcus furiosusArgonaute (PfAgo) emerged as a novel endonuclease for the nucleic acid test recently. However, the input of exogenous guide DNA (gDNA) to activate PfAgo has reduced its flexibility. In this work, an enzyme-assisted endogenous gDNA generation-mediated PfAgo for the target detection strategy, termed EGG-PAD, was proposed. With the aid of EcoR Ι, the target double-strand DNA was cut, producing a phosphate group at the 5' end, functioning as gDNA to activate PfAgo for nucleic acid detection. The applicability of this assay was tested in the detection ofAlicyclobacillus acidoterrestris, a bacterium causing the spoilage of fruit juice, showing excellent sensitivity and specificity, ascribed to the "duplex amplification and triple insurance" mechanism. Moreover, EGG-PAD exhibited superior versatility in the identification of common foodborne pathogens. This powerful platform could also be an on-site test tool for detecting nucleic acid-containing organisms such as tumor cell, pathogen, and virus in the future.


Assuntos
Alicyclobacillus , Pyrococcus furiosus , Pyrococcus furiosus/genética , DNA , Sucos de Frutas e Vegetais , Alicyclobacillus/genética
9.
World J Surg Oncol ; 22(1): 40, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38297303

RESUMO

BACKGROUND: The application of machine learning (ML) for identifying early gastric cancer (EGC) has drawn increasing attention. However, there lacks evidence-based support for its specific diagnostic performance. Hence, this systematic review and meta-analysis was implemented to assess the performance of image-based ML in EGC diagnosis. METHODS: We performed a comprehensive electronic search in PubMed, Embase, Cochrane Library, and Web of Science up to September 25, 2022. QUADAS-2 was selected to judge the risk of bias of included articles. We did the meta-analysis using a bivariant mixed-effect model. Sensitivity analysis and heterogeneity test were performed. RESULTS: Twenty-one articles were enrolled. The sensitivity (SEN), specificity (SPE), and SROC of ML-based models were 0.91 (95% CI: 0.87-0.94), 0.85 (95% CI: 0.81-0.89), and 0.94 (95% CI: 0.39-1.00) in the training set and 0.90 (95% CI: 0.86-0.93), 0.90 (95% CI: 0.86-0.92), and 0.96 (95% CI: 0.19-1.00) in the validation set. The SEN, SPE, and SROC of EGC diagnosis by non-specialist clinicians were 0.64 (95% CI: 0.56-0.71), 0.84 (95% CI: 0.77-0.89), and 0.80 (95% CI: 0.29-0.97), and those by specialist clinicians were 0.80 (95% CI: 0.74-0.85), 0.88 (95% CI: 0.85-0.91), and 0.91 (95% CI: 0.37-0.99). With the assistance of ML models, the SEN of non-specialist physicians in the diagnosis of EGC was significantly improved (0.76 vs 0.64). CONCLUSION: ML-based diagnostic models have greater performance in the identification of EGC. The diagnostic accuracy of non-specialist clinicians can be improved to the level of the specialists with the assistance of ML models. The results suggest that ML models can better assist less experienced clinicians in diagnosing EGC under endoscopy and have broad clinical application value.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Endoscopia , Aprendizado de Máquina
10.
Anal Bioanal Chem ; 416(4): 1057-1067, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38117324

RESUMO

Here, an enzyme-free lateral flow aptasensor was designed by target-induced strand-displacement effect and followed by the activation of multi-component nucleic acid enzyme (MNAzyme)-mediated cleavage to enable rapid and portable ochratoxin A (OTA) detection. The substrate was prepared as an oligonucleotide strand modified with magnetic beads (MB) and human chorionic gonadotropin (hCG). The interaction of OTA with the aptamer induces the release of blocking DNA, which hybridized with three separated subunits of DNA, forming a sequence-specific MNAzyme catalytic core. This core subsequently initiated an enzyme-free MNAzyme cleavage reaction in the presence of the Mg2+ cofactor, cleaving a special substrate and releasing both the incomplete MNAzyme catalytic core and hCG-DNA probe. The incomplete MNAzyme catalytic core was then recognized by substrates once again, triggering a cascade recycling cleavage and resulting in the generation of a larger number of hCG-DNA probes. After magnetic enrichment, the free hCG-DNA probes flow through the pregnancy test strip (PTS) to the T line, generating a colorimetric readout that unequivocally confirms the presence of the target OTA. This work leverages the efficient enzyme-free cleavage amplification of MNAzyme and the PTS-based portable detection device, presenting a biosensing strategy with significant potential for sensitive and portable OTA detection. This method exhibited remarkable sensitivity and selectivity for OTA detection, boasting a detection limit of 5 nM. The present study successfully demonstrated the practical application of this method on real samples, offering a viable alternative for rapid and portable detection of mycotoxins.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Micotoxinas , Ocratoxinas , Humanos , Micotoxinas/análise , Ocratoxinas/análise , Técnicas Biossensoriais/métodos , DNA , Catálise , Sondas de DNA , Limite de Detecção
11.
J Agric Food Chem ; 71(29): 11217-11227, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37439414

RESUMO

Patulin (PAT) is a water-soluble mycotoxin that causes digestive tract damage and liver and kidney function abnormalities. The current control approaches only reduce the amount of PAT in raw materials and food, which is difficult to remove once ingested in the body. In this study, lignin-based cross-linked particles loaded with chlorogenic acid were prepared, which intervened the liver and colon damage caused by PAT in mice. In the simulated digestion process in vitro, the accumulated adsorption capacity of the LB/CA-SH for PAT was 0.934 mg/g. LB/CA-SH intervention reversed the shortening of the colon length, alleviated the changes in the activities of antioxidant enzymes, and reduced the levels of oxidation markers protein carbonyl and malondialdehyde in the colon tissue of the model group. The absorption of sorbent alleviated the decrease of organ index and the abnormality of serum biochemical indexes (alanine aminotransferase, aspartate aminotransferase, urea nitrogen, and uric acid) caused by PAT. These results support the potential of using LB/CA-SH as a novel protective agent to reduce the toxicity of PAT.


Assuntos
Patulina , Camundongos , Animais , Patulina/toxicidade , Ácido Clorogênico , Lignina , Adsorção , Colo
12.
J Cancer Res Clin Oncol ; 149(14): 12821-12834, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37458804

RESUMO

BACKGROUND: Existing predictive models often focus solely on overall survival (OS), neglecting the bias that other causes of death might introduce into survival rate predictions. To date, there is no strict predictive model established for cancer-specific survival (CSS) in patients with intermediate and advanced colon cancer after receiving surgery and chemotherapy. METHODS: We extracted the data from the Surveillance, Epidemiology, and End Results (SEER) database on patients with stage-III and -IV colon cancer treated with surgery and chemotherapy between 2010 and 2015. The cancer-specific survival (CSS) was assessed using a competitive risk model, and the associated risk factors were identified via univariate and multivariate analyses. A nomogram predicting 1-, 3-, and 5-year CSS was constructed. The c-index, area under the curve (AUC), and calibration curve were adopted to assess the predictive performance of the model. Additionally, the model was externally validated. RESULTS: A total of 18 risk factors were identified by univariate and multivariate analyses for constructing the nomogram. The AUC values of the nomogram for the 1-, 3-, and 5-year CSS prediction were 0.831, 0.842, and 0.848 in the training set; 0.842, 0.853, and 0.849 in the internal validation set; and 0.815, 0.823, and 0.839 in the external validation set. The C-index were 0.826 (se: 0.001), 0.836 (se: 0.002) and 0.763 (se: 0.013), respectively. Moreover, the calibration curve showed great calibration. CONCLUSION: The model we have constructed is of great accuracy and reliability, and can help physicians develop treatment and follow-up strategies that are beneficial to the survival of the patients.

13.
Int J Biol Macromol ; 245: 125489, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37348583

RESUMO

Supersaturating drug delivery system (SDDS) is a promising approach to enhance the solubility of hydrophobic functional components. However, SDDS is thermodynamically unstable and crystallization tends to occur. In this work, curcumin was used as a model compound, and the crystallization inhibitory effect of konjac glucomannan (KGM), sodium alginate (SA) and xanthan gum (XTG) on curcumin in supersaturated solution was investigated. Amorphous solubility of curcumin was determined using ultraviolet extinction, fluorescence spectroscopy and dynamic light scattering methods. Nucleation induction time (NIT) and crystal growth rate of curcumin were evaluated using ultraviolet probe in the absence and presence of various natural polysaccharides (NPs). Results showed that amorphous solubility of curcumin was approximately 30 µg/mL in pH 6.8 phosphate buffer. NPs used in this work restrained nucleation or crystal growth of curcumin effectively. The NITs of curcumin in the absence of NPs and in the presence of XTG, KGM and SA (1 µg/mL) were 3.7, 60.7, 20.0 and 8.0 min, respectively. The crystal growth rate of curcumin in the absence of NPs and in the presence of XTG, SA and KGM (1 µg/mL) were 0.0103, 0.00752, 0.00286 and 0.000306 min-1, respectively. The nucleation inhibitory effect of NPs on curcumin was ranked as XTG > KGM > SA. The order of crystal growth inhibition capacity of NPs was KGM > SA > XTG. In conclusion, NPs could be incorporated into SDDS to maintain supersaturation of hydrophobic components for enhanced bioavailability.


Assuntos
Curcumina , Cristalização , Curcumina/farmacologia , Alginatos , Mananas/química , Solubilidade
14.
Food Chem ; 424: 136349, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37244185

RESUMO

Acrylamide (AA) and heterocyclic aromatic amines (HAAs), as classic hazards produced during food thermal processing, have been widely concerned, but because of their polarity difference, it is very difficult to detect these contaminants simultaneously. Herein, novel cysteine (Cys)-functionalized magnetic covalent organic frameworks (Fe3O4@COF@Cys) were synthesized via a thiol-ene click strategy and then used as adsorbents for magnetic solid-phase extraction (MSPE). Benefiting from the hydrophobic properties of COFs and the modification of hydrophilic Cys, AA and HAAs could be enriched simultaneously. Then, a rapid and reliable method based on MSPE coupled with HPLC-MS/MS was developed for the simultaneous detection of AA and 5 HAAs in thermally processed foods. The proposed method showed good linearity (R2 ≥ 0.9987) with satisfactory limits of detection (0.012-0.210 µg kg-1) and recoveries (90.4-102.8%). Actual sample analysis showed that the levels of AA and HAAs in French fries were affected by frying time and temperature, water activity of samples, content and type of reaction precursors, and reuse of oils.


Assuntos
Estruturas Metalorgânicas , Cromatografia Líquida de Alta Pressão , Estruturas Metalorgânicas/química , Espectrometria de Massas em Tandem , Cisteína , Acrilamida , Alimento Processado , Aminas/química , Fenômenos Magnéticos , Extração em Fase Sólida/métodos , Limite de Detecção
15.
Food Chem ; 415: 135735, 2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-36863235

RESUMO

Advanced glycation end products (AGEs) are formed by a series of chemical reactions of amino acids, peptides, proteins, and ketones at normal temperature or heated non-enzymatic conditions. A large amount of AGEs derived from Maillard Reaction (MR) during the process of food heat-processing. After oral intake, dietary AGEs are converted into biological AGEs through digestion and absorption, and accumulated in almost all organs. The safety and health risk of dietary AGEs have attracted wide attention. Increasing evidence have shown that uptake of dietary AGEs is closely related to the occurrence of many chronic diseases, such as diabetes, chronic kidney disease, osteoporosis, and Alzheimer's disease. This review summarized the most updated information of production, bio-transport in vivo, detection technologies, and physiological toxicity of dietary AGEs, and also discussed approaches to inhibit dietary AGEs generation. Impressively, the future opportunities and challenges on the detection, toxicity, and inhibition of dietary AGEs are raised.


Assuntos
Diabetes Mellitus , Produtos Finais de Glicação Avançada , Humanos , Produtos Finais de Glicação Avançada/metabolismo , Produtos Finais da Glicação Avançada em Alimentos , Dieta , Reação de Maillard
16.
Food Chem ; 413: 135553, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36745944

RESUMO

Inspired by a biomineralization behavior, we prepared a nanoflower-like artificial clickase (namely LCN clickase) for portable and sensitive click SERS immunoassay of foodborne bacterial pathogen. Encouraged by its high click catalytic activity to trigger Cu(I)-catalyzed azide-alkyne cycloaddition reaction, LCN clickase was successfully used for establishing a novel click SERS immunoassay by combining the clickase-mediated SERS signal variation at Raman-silent region. The developed method not only effectively eliminated the interferences between Raman reporter and biological species, but also reduced the complex sample matrix interference. Compared with traditional CuAAC-based immunoassays, the established method avoided the superfluous dissolution process of nanocatalysts and eliminated the requirement of reducing agent during detection, thereby shortening detection time and improving detection reliability. Impressively, the proposed method showed high selectivity and sensitivity for detection of Salmonella enterica serovar Paratyphi B with a low LOD of 20 CFU/mL, exhibiting a great potential in detection of foodborne bacterial pathogen in food samples.


Assuntos
Bactérias , Salmonella paratyphi B , Reprodutibilidade dos Testes , Imunoensaio/métodos , Análise Espectral Raman/métodos
17.
Crit Rev Food Sci Nutr ; 63(15): 2544-2558, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34523362

RESUMO

Fungal contamination of food, which causes large economic losses and public health problems, is a global concern. Chemical methods are typically used in the food industry to inhibit the growth of spoilage fungus, but there are several drawbacks of chemical methods. Thus, the development of consumer-friendly and ecologically sustainable biological preservation technology has become a hot spot in food research. As a natural biological control agent, lactic acid bacteria (LAB) is a good choice in food preservation due to its antifungal properties. In order to screen and identify new antifungal LAB and antifungal compounds, this review compares three screening methods (overlay method, agar diffusion method, and microplate inhibition method) of antifungal LAB and summarizes the separation and purification techniques of antifungal compounds. A discussion of the effects of LAB, media, temperature, pH, and incubation period on the antifungal activity of LAB to highlight the antifungal properties of LAB for future studies then follows. Additionally, the antifungal mechanism of LAB is elucidated from three aspects: 1) LAB cells, 2) antifungal compounds, and 3) co-cultivation. Finally, research regarding antifungal LAB in food preservation (fruits, vegetables, grain cereals, bakery products, and dairy products) is summarized, which demonstrates the potential application value of LAB in food.


Assuntos
Lactobacillales , Antifúngicos/farmacologia , Fungos , Microbiologia de Alimentos , Conservação de Alimentos/métodos
18.
Food Chem ; 399: 133843, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35998488

RESUMO

A facile approach was proposed for the preparation of boric acid-functionalized core-shell structured magnetic covalent organic framework (COF) nanocomposites through employing the Fe3O4 nanoparticles as magnetic core, boric acid-functionalized COFs as the shell via sequential post-synthetic modification (denoted as Fe3O4@COF@BA). The synthesized nanocomposites showed large specific surface area, high magnetic responsiveness, and desirable chemical and thermal stability. Combined with HPLC-MS/MS, the as-prepared Fe3O4@COF@BA composite was applied as a sorbent for magnetic solid-phase extraction (MSPE) of endocrine disrupting compounds (EDCs) from meat samples. Under optimal conditions, the method displays low limits of detection (LODs, 0.08-0.72 µg kg-1) and good precision with relative standard deviations (RSD) lower than 5.4 %. The approach was successfully employed for the extraction and detection of EDCs in blank and spiked beef, chicken and pork samples with recovery ranging from 88.8 to 104.2 %.


Assuntos
Disruptores Endócrinos , Estruturas Metalorgânicas , Adsorção , Animais , Ácidos Bóricos , Bovinos , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Fenômenos Magnéticos , Carne/análise , Estruturas Metalorgânicas/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem
19.
ChemSusChem ; 15(23): e202201394, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36116112

RESUMO

Inorganic perovskite solar cells have attracted wide attention due to their excellent thermodynamic stability and suitable bandgap as the top absorber materials for tandem solar cells. However, the power conversion efficiencies (PCEs) of the perovskite cells can be considerably limited by the non-radiative energy loss caused by grain boundaries and surfaces. Here, the synergistic functionalization of CsPbI2 Br perovskites was demonstrated by using a metal-organic complex. Experimental and theoretical studies revealed that the adsorption energy of the passivator could be a good descriptor to evaluate the surface passivation effect. The cooperative adsorption could eliminate the unsaturated surface sites, reduce the surface energy, and thus benefit device performance. The CsPbI2 Br solar cells passivated by zinc diethyldithiocarbamate showed a champion power conversion efficiency of 17.15 % and retained 94 % of their initial efficiency after working under 1 sun illumination for 720 h in N2 atmosphere.

20.
Small Methods ; 6(10): e2200794, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36114150

RESUMO

Infectious pathogens cause severe human illnesses and great deaths per year worldwide. Rapid, sensitive, and accurate detection of pathogens is of great importance for preventing infectious diseases caused by pathogens and optimizing medical healthcare systems. Inspired by a microbial defense system (i.e., CRISPR/ CRISPR-associated proteins (Cas) system, an adaptive immune system for protecting microorganisms from being attacked by invading species), a great many new biosensors have been successfully developed and widely applied in the detection of infectious viruses and pathogenic bacteria. Moreover, advanced nanotechnologies have also been integrated into these biosensors to improve their detection stability, sensitivity, and accuracy. In this review, the recent advance in CRISPR/Cas systems-based nano/biosensors and their applications in the detection of infectious viruses and pathogenic bacteria are comprehensively reviewed. First of all, the categories and working principles of CRISPR/Cas systems for establishing the nano/biosensors are simply introduced. Then, the design and construction of CRISPR/Cas systems-based nano/biosensors are comprehensively discussed. In the end, attentions are focused on the applications of CRISPR/Cas systems-based nano/biosensors in the detection of infectious viruses and pathogenic bacteria. Impressively, the remaining opportunities and challenges for the further design and development of CRISPR/Cas system-based nano/biosensors and their promising applications are proposed.


Assuntos
Técnicas Biossensoriais , Proteínas Associadas a CRISPR , Doenças Transmissíveis , Viroses , Vírus , Humanos , Sistemas CRISPR-Cas/genética , Bactérias/genética , Viroses/diagnóstico , Vírus/genética
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