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1.
Exp Biol Med (Maywood) ; 248(18): 1588-1597, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37749991

RESUMO

Increasing evidence indicates that deep venous thrombosis (DVT) is a common peripheral vascular disease. This study aims to investigate the mechanisms of thioredoxin-interacting protein (TXNIP) and nod-like receptor protein 3 (NLRP3) inflammasome in deep venous thrombosis (DVT). A total of 66 Sprague-Dawley (SD) rats were employed to conduct DVT model. DVT rat was treated with silenced TXNIP (si-TXNIP) lentivirus and MCC950 (a NLRP3 inhibitor). The thrombosis weight and weight/length ratio, tissue factor, inflammatory factors, superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) were measured. Hematoxylin-eosin (H&E) staining was used to investigate the pathological change. Western blotting was used to determine the protein expression level. The expression level of thioredoxin (TRx) was suppressed, whereas TXNIP and NLRP3 were elevated in DVT rat. Si-TXNIP or MCC950 could reduce the thrombosis weight and weight/length ratio, ameliorate the pathological change, and decrease inflammatory reaction. Mechanistically, si-TXNIP or MCC950 inhibited the expression levels of TXNIP, NLRP3, and interleukin (IL)-1ß while elevating the TRx level, thereby suppressing the DVT. Our study indicated that si-TXNIP or MCC950 injection rescued the injury of vein induced by DVT. The possible mechanisms connected with the inhibition of TXNIP and NLRP3. TXNIP is a possible therapeutic target for DVT.


Assuntos
Trombose , Trombose Venosa , Animais , Ratos , Proteínas de Ciclo Celular/metabolismo , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas NLR/metabolismo , Estresse Oxidativo , Ratos Sprague-Dawley , Tiorredoxinas/metabolismo
2.
Biosens Bioelectron ; 238: 115559, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37542976

RESUMO

Neonicotinoids such as thiamethoxam (TMX) were widely used in agricultural production and tended to accumulate in the environment, potentially harming human and ecosystem health. To enable widespread monitoring of TMX residues, it was essential to design a reliable and sensitive detection method. Here, we developed a novel smartphone-enablled molecularly imprinted ratiometric fluorescence sensing system for selective on-site detection of TMX. It was based on blue-emission carbon dots (CDs) wrapped with a molecularly imprinted layer (B-CDs@MIPs), which provided the response signal, while red-emission CDs (R-CDs) served as an internal reference. The fluorescence signal ratio of the sensor increased with the TMX concentration, resulting in an obvious fluorescence color change from red to blue. The sensor exhibited a satisfactory limit of detection (LOD) of 13.5 nM in fluorescence analysis while LOD of 70.1 nM in visual determination. In addition, the sensing system was validated using food and environment samples, exhibiting recoveries from 91.40% to 105.7%, indicating excellent reliability for TMX detection in actual samples. Thus, the sensing system developed in this study offered promising prospects for visual detection of pesticide residues in complex environmental samples.


Assuntos
Técnicas Biossensoriais , Impressão Molecular , Pontos Quânticos , Humanos , Pontos Quânticos/química , Tiametoxam , Carbono/química , Ecossistema , Reprodutibilidade dos Testes , Impressão Molecular/métodos , Espectrometria de Fluorescência/métodos , Corantes Fluorescentes/química , Técnicas Biossensoriais/métodos , Limite de Detecção
3.
Mikrochim Acta ; 190(8): 336, 2023 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-37515610

RESUMO

A novel magnetic nanozyme Fe3O4@MXene-Au nanocomposite, which possessed higher peroxidase-like activity than that of Fe3O4 nanoparticles and Fe3O4@MXene nanocomposites, was developed. The outstanding magnetic properties of the nanozyme endowed it with the ability of simple and rapid separation, achieving great recyclability. Based on Fe3O4@MXene-Au nanocomposites and glucose oxidase (Glu Ox), a highly selective colorimetric biosensor for glucose detection was developed. Fe3O4@MXene-Au nanocomposites can catalyze H2O2 produced from glucose catalyzed by glucose oxidase to ·OH and oxidize colorless 3,3',5,5'-tetramethylbenzidine (TMB) to blue oxidized TMB (oxTMB) with a significant absorbance at 652 nm. The linear range of glucose was 0-1.4 mM under optimal conditions, with a limit of detection (LOD) of 0.11 mM. Glucose in human whole blood was successfully detected with satisfactory recoveries. Furthermore, a facile agarose hydrogel detection platform was designed. With smartphone software, glucose detection can be realized by the agarose hydrogel platform, demonstrating the potential in on-site and visual detection of glucose.


Assuntos
Técnicas Biossensoriais , Nanocompostos , Humanos , Peroxidase , Glucose , Colorimetria , Glucose Oxidase , Smartphone , Peróxido de Hidrogênio , Sefarose , Peroxidases
4.
RSC Adv ; 13(20): 13824-13833, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37152563

RESUMO

The compound 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), one of the tobacco specific nitrosamines (TSNAs), is widely recognized as a major carcinogen found in tobacco products, environmental tobacco smoke and wastewater. Thus, a selective enrichment and sensitive detection method for monitoring the risk of NNK exposure is highly desirable. In this study, a magnetic molecularly imprinted polymer (MMIP) functionalized with dendritic nanoclusters was synthesized to selectively recognize NNK via the dummy template imprinting strategy, aiming to avoid residual template leakage and increase the imprinting efficiency. The nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, as well as vibrating sample magnetometry (VSM) and nitrogen adsorption/desorption analysis. The resulting MMIPs exhibited high adsorption capacity, fast binding kinetics and good selectivity for trace amounts of NNK. A rapid, low cost and efficient method for detecting NNK in tobacco products was established using magnetic dispersive solid-phase extraction coupled with HPLC-DAD with a good linear range of 0.1-250 µg mL-1. The limit of detection (LOD) and limit of quantification (LOQ) of NNK were 13.5 and 25.0 ng mL-1, respectively. The average recoveries were 87.8-97.3% with RSDs lower than 3%. The results confirmed that the MMIPs could be used as an excellent selective adsorbent for NNK, with potential applications in the pretreatment of tobacco products.

5.
Mikrochim Acta ; 189(12): 467, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36422716

RESUMO

A selective method for the determination of myosmine (a tobacco alkaloid) was developed using molecularly imprinted polymers (MIPs) based on Fe3O4@SiO2 and PAMAM dendrimers. Fe3O4@SiO2 with excellent magnetism and rapid separation performance was chosen as carrier for the MIPs. Moreover, the MIPs modified with PAMAM dendrimers exhibited a regular structure and abundant functional groups, which improve the efficiency of imprinting sites. The myosmine concentration was measured by HPLC with PDA detector, and the UV detection wavelength was set to 200 nm. The linear range of this assay was 13.2-400 mg/L with a correlation coefficient of 0.999, and the detection limit was 4.0 mg/L (S/N = 3). The MIPs have been used for the determination of myosmine in cigarettes, and the recovery range was 84.2-93.5%, with RSD values in the range 0.41-3.1%. In conclusion, our MIPs combine advantages of simple preparation and remarkable selectivity, which gives them excellent application prospects for the sensitive determination of trace myosmine in tobacco products.


Assuntos
Alcaloides , Dendrímeros , Impressão Molecular , Produtos do Tabaco , Polímeros Molecularmente Impressos , Impressão Molecular/métodos , Dióxido de Silício/química , Polímeros/química
6.
Inflammation ; 45(6): 2268-2279, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35655037

RESUMO

Deep vein thrombosis (DVT) has become a prevalent and increasingly serious problem globally and resveratrol (Res) is a natural antitoxin that inhibits arterial thrombosis. To investigate the effect of Res on DVT and further explore its mechanism, thrombosis was monitored at different time points and the pathological changes occurring in the inferior vena cava (IVC) and lung tissue were observed in Sprague-Dawley rats. The protein expression of HIF-1α and NLRP3 in the IVC and lung tissue and the concentrations of D-dimer (D2D), prothrombin fragment 1 + 2 (F1 + 2), interleukin-1ß (IL-1ß), caspase-1, and tissue factor (TF) in the plasma were determined. After setting different doses of Res groups and using low-molecular-weight heparin (LMWH) as a positive control to determine the effective experimental dose of Res, rats were further divided into sham, DVT, HIF-1α inhibitor, Res, and HIF-1α inhibitor + Res groups. The above indicators were tested repeatedly. The DVT was formed on the 1st day of modeling. With the extension of time, DVT was gradually institutionalized and finally recanalized. Lesions in the IVC and lung tissue were effectively ameliorated, and thrombosis was significantly decreased in the LMWH or 60 mg/kg Res-treated groups. The levels of D2D, F1 + 2, IL-1ß, caspase-1, TF, and the expression of HIF-1α and NLRP3 were significantly reduced in the HIF-1α inhibitor, Res, and HIF-1α inhibitor + Res groups. Res can ameliorate DVT in rats by inhibiting HIF-1α/NLRP3 pathway, which provides a novel therapeutic strategy for DVT treatment.


Assuntos
Heparina de Baixo Peso Molecular , Trombose Venosa , Ratos , Animais , Resveratrol/farmacologia , Resveratrol/uso terapêutico , Ratos Sprague-Dawley , Heparina de Baixo Peso Molecular/farmacologia , Heparina de Baixo Peso Molecular/uso terapêutico , Proteína 3 que Contém Domínio de Pirina da Família NLR , Subunidade alfa do Fator 1 Induzível por Hipóxia , Trombose Venosa/tratamento farmacológico , Trombose Venosa/patologia , Caspases
7.
Colloids Surf B Biointerfaces ; 212: 112347, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35085939

RESUMO

High plasma urate is closely related to gout, cardiovascular and other diseases. Therefore, monitoring the content of uric acid (UA) in plasma is of great significance for the treatment of gout and the prevention of other related diseases. Herein, a biosensor based on the biomimetic oxidase Fe3O4 nanoparticles (NPs) @MnO2 nanosheets (Fe3O4@MnO2 NS) was constructed for colorimetric determination of UA. MnO2 NS is an efficient biomimetic oxidase, and we found that the intrinsic oxidase activity of MnO2 NS doped with Fe3O4 NPs can be significantly enhanced. The chromogenic substrate TMB can be catalyzed by Fe3O4 @MnO2 NS to generate blue oxidized TMB, and UA can decompose the MnO2 NS to inhibit the color reaction of TMB selectively, thereby realizing the quantitative detection of UA. In addition, the UA biosensor can perform colorimetric analysis of UA level through three methods: naked eye, smartphone and ultraviolet-visible (UV-vis) spectrophotometer. The linear ranges of UV-vis spectrophotometry and colorimetry with smartphone were 1-70 µM and 200-650 µM, respectively, and the limits of detection (LOD) were 0.27 µM and 21 µM. The analysis results of human plasma samples showed that the method had good selectivity and practicability.


Assuntos
Técnicas Biossensoriais , Colorimetria , Benzidinas/química , Biomimética , Técnicas Biossensoriais/métodos , Colorimetria/métodos , Humanos , Compostos de Manganês/química , Oxirredução , Óxidos/química , Oxirredutases/química , Ácido Úrico
8.
Food Chem ; 368: 130838, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34425336

RESUMO

Herein, using Fe3O4 nanoparticles (Fe3O4 NPs) as a magnetic artificial peroxidase, an "on-off" ratiometric photoluminescence sensor with high-sensitivity and high-selectivity for coumarin was constructed based on photoinduced electron transfer (PET) between 7-hydroxycoumarin and rhodamine B (RB). The results showed that Fe3O4 NPs catalyzed H2O2 to generate nucleophilic group ·OH, which attacked the active site of coumarin and produced strong fluorescent 7-hydroxycoumarin molecules. Then, the fluorescence of RB was quenched with 7-hydroxycoumarin through the PET effect. The ratio signal generated in the above process was used for the quantitative detection of coumarin. Under optimized conditions, the linear range 0.5-25 mg/L was acquired for coumarin with the detection limit of 0.016 mg/L. This method had excellent selectivity and the recovery rate was 81.8%-106.8% with the relative standard deviation less than 5.6%, so it can be used for the quantitative analysis of coumarin in complex matrix samples.


Assuntos
Peróxido de Hidrogênio , Nanopartículas , Cumarínicos , Fluorescência , Tomografia por Emissão de Pósitrons
9.
ACS Biomater Sci Eng ; 7(6): 2767-2773, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-33940791

RESUMO

Hydrogen peroxide (H2O2) has been reported to mediate a variety of physiological and pathological processes in living systems. In this work, a biosensor for determination of H2O2 was prepared by using an HRP/Ti3C2/Nafion film-modified glassy carbon electrode (GCE). Ti3C2 nanosheets with remarkable conductivity and high specific surface area were chosen as carriers for HRP. Moreover, this biosensor modified with HRP has a specific catalytic effect on H2O2. The difference in peak current could reflect the quantitative change of H2O2. The linear range of the biosensor is 5-8000 µM, and the detection limit is 1 µM (S/N = 3). This biosensor was used to detect H2O2 in clinical serum samples of normal controls and patients with acute myocardial infarction (AMI) before and after percutaneous coronary intervention (PCI). The results showed that the difference between normal controls and patients is significant (P < 0.05), as well as the difference for patients before and after PCI (P < 0.01), but no significant difference existed between postoperative patients and normal controls. This biosensor has the advantages of simple preparation, high sensitivity, and quick detection, showing potential application in clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Infarto do Miocárdio , Intervenção Coronária Percutânea , Polímeros de Fluorcarboneto , Humanos , Peróxido de Hidrogênio , Infarto do Miocárdio/diagnóstico , Titânio
10.
Exp Ther Med ; 7(1): 103-108, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24348773

RESUMO

This study aimed to compare the efficacy and safety of thrombolytic and anticoagulant therapy for acute submassive pulmonary embolism (PE). A retrospective evaluation was performed on 25 consecutive inpatients with acute submassive PE treated by thrombolytic therapy and 25 earlier consecutive inpatients with acute submassive PE treated by anticoagulant therapy. No statistically significant difference in clinical curative effect was identified between the thrombolysis and anticoagulation groups (P>0.05). Following 24 h of therapy, the improvement rates of dyspnea and revascularization in the thrombolysis group achieved statistical significance compared with those of the anticoagulation group (P<0.01 for each). The PO2 level of the thrombolysis group (81.18±5.66 mmHg) was notably higher than that of the anticoagulation group and the difference was statistically significant (P<0.01). The pulmonary arterial pressures of the thrombolysis group (51.21±6.86 mmHg) were significantly lower than those of the anticoagulation group (60.64±5.17 mmHg) (P<0.01). Furthermore, the difference between the hemorrhage rates of the two groups was statistically significant (P<0.05). Thrombolysis was shown to rapidly relieve dyspnea, reduce pulmonary arterial pressure and revascularize the embolized blood vessels. However, the hemorrhage rate of the thrombolysis group was higher than that of the anticoagulation group. The overall efficacies and fatality rates of the thrombolysis and anticoagulation groups were similar.

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