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1.
Clin Exp Rheumatol ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38436270

RESUMO

OBJECTIVES: The study aimed to explore the value of texture analysis of radiomics based on the short tau inversion recovery (STIR) sequence to evaluate the activity of bone marrow oedema of sacroiliac joints in early AS. METHODS: 43 patients with early AS whose data were randomly divided into the training cohort (n=116) and verification cohort (n=56) according to the ratio of 7:3. The optimal feature subsets were obtained by Mann-Whitney U-test, the minimum-Redundancy Maximum-Relevancy (mRMR), and then least absolute shrinkage and selection operator (LASSO) using these texture feature parameters, which were used to construct the final prediction model and obtained the Radscore. The ROC curve was performed to evaluate the performance of the model. The Spearman correlation test was used to analyse the correlation of various indicators. RESULTS: In the training cohort, to differentiate early AS sacroiliac joint bone marrow oedema between the active and stable groups, the AUCs of the Radscore, SPARCC and ADC were 0.81, 0.91, 0.78, respectively. In the validation cohort, the AUCs were 0.87, 0.89, 0.85. In the two cohorts, there were no significant differences in AUCs between values of the Radscore and SPARCC, ADC (p>0.05). There was a significant difference in AUC between SPARCC and ADC in the training cohort (p<0.05), with no statistical significance in the validation cohort (p>0.05). The correlations were all low between the Radscore values and the values of ESR, CRP, tI, ASDAS-ESR and ASDAS-CRP (p<0.05). CONCLUSIONS: Radiomics analysis based on STIR texture analysis has a good prediction for the evaluation of bone marrow oedema activity of sacroiliac joints in AS. It can be a new non-invasive and objective evaluation method for AS activity.

2.
Chem Biodivers ; 20(1): e202200822, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36527339

RESUMO

The traditional Chinese medicine of fermented medicine may be under the involvement of multiple strains and the interaction between these microorganisms. Liu Shenqu (Massa Medicata Fermentata, MMF) is one of the most widely used fermented medicines, whose potential processing mechanism is still unclear. In this work, UPLC/MS and GNPS methods were employed to rapidly predict chemical compositions in MMF. Moreover, the dynamic changes of strains, chemical compositions and anti-inflammatory activity of MMF during fermentation process were investigated, and subsequently strains-chemical compositions-efficacy interactions were revealed by Pearson correlation analysis and partial least squares regression (PLSR) analysis. As a result, 24 components were identified, and the potential strains including Bacillus, Burkholderia_Caballeronia_Paraburkholderia, Enterobacter, Aspergillus heterocaryoticus, Rhizopus arrhizus, Kazachstania bulderi, which related to the production of anti-inflammatory active ingredients were exposed. These results demonstrated chemical compositions-strains-efficacy interactions during fermentation of MMF, and provide reference for the exploration of the processing mechanism of MMF.


Assuntos
Medicamentos de Ervas Chinesas , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Medicina Tradicional Chinesa/métodos , Anti-Inflamatórios/farmacologia
3.
Chem Biodivers ; 18(8): e2100314, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34101351

RESUMO

One new dioxolanone derivative, guignardianone G (1) and twelve known compounds (2-13) were isolated from the 95 % ethanol extract of the plant endophytic fungus Phyllosticta capitalensis cultured in rice medium. Among these known compounds, isoaltenuene (3), brassicasterol (7), 5,6-epoxyergosterol (8), citreoanthrasteroid A (9), demethylincisterol A (10), and chaxine C (11) were reported from Phyllosticta sp. for the first time. The structure of 1 was elucidated by 1D- and 2D-NMR experiments and HR-ESI-MS data analysis, and its absolute configuration was established through the comprehensive use of the methods of modified Mosher methods, calculations of ECD spectra and optical rotation values. The neuroprotective activity of compounds (1-9, 11-13) were evaluated on PC12 cells damage induced by glutamate, and compounds 9 and 12 showed potential neuroprotective activities with half effective concentration (EC50 ) of 24.2 and 33.9 µM, respectively.


Assuntos
Ascomicetos/química , Hamamelidaceae/microbiologia , Fármacos Neuroprotetores/química , Animais , Ascomicetos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Dioxolanos/química , Dioxolanos/isolamento & purificação , Dioxolanos/farmacologia , Endófitos , Ácido Glutâmico/farmacologia , Espectroscopia de Ressonância Magnética , Conformação Molecular , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Células PC12 , Ratos
4.
Mikrochim Acta ; 188(7): 241, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34212233

RESUMO

Based on platinum nanoparticle-embedded raspberry-liked SiO2, a sensitive and selective electrochemical sensor was developed for simultaneous determination of eugenol (EU) and methyleugenol (MEU). Raspberry-liked SiO2 (RL-SiO2) was characterized with open pores on the surface, which can be used as a path for utilizing the inner space fully. So, platinum nanoparticles (Pt NPs) could be embedded in the inner and outer surface of RL-SiO2. As a carrier, RL-SiO2 not only avoided the agglomeration of the Pt NPs but also improved the catalytic performance. Therefore, the prepared Pt NPs@RL-SiO2/GCE exhibited excellent electrocatalytic activity for simultaneous determination of EU and MEU; the linearity ranges were 0.50 ~ 60 µmol/L for EU at a working potential of 0.65 V (vs. saturated calomel electrode) and 0.50 ~ 50 µmol/L for MEU at a working potential of 1.10 V; the detection limits were 0.12 µmol/L and 0.16 µmol/L (S/N=3); and the relative standard deviations (RSDs) were 3.2% and 4.5%, respectively. In addition, Pt NPs@RL-SiO2/GCE was successfully applied to the analysis of fish samples; the obtained recoveries were between 92.0 and 107%. Notably, the results conducted on samples were highly consistent with those obtained from high-performance liquid chromatography. It can be concluded that the study provided a simple method for simultaneous electrochemical determination of EU and MEU in fish samples. Schematic illustration of the preparation of RL-SiO2@Pt NPs/GCE for simultaneous determination of eugenol and methyleugenol in fish samples.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Eugenol/análogos & derivados , Eugenol/química , Nanopartículas/química , Platina/química , Dióxido de Silício/química
5.
Phytochemistry ; 217: 113918, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37952710

RESUMO

Four undescribed sesquiterpene-shikimates (1-4), eight undescribed monoterpene-shikimates (5-12), together with two known ones were isolated and identified from the 95% ethanol extract of the plant endophytic fungus Phyllosticta capitalensis cultured in rice medium. Capitalensis A (1) was identified as the first sesquiterpene-shikimate-conjugated spirocyclic meroterpenoid degradation product, while capitalensis B (2) is a sesquiterpene-shikimate-conjugated spirocyclic meroterpenoid with a unique D-ring formed by a C-2-O-C-9' connection. The structures of these previously undescribed compounds were elucidated by multiple techniques, including IR, HR-ESI-MS, and NMR analysis. Furthermore, their absolute configurations were established through the comprehensive approach that involved the calculations of ECD spectra, optical rotation values, and single-crystal X-ray analysis. Moreover, the anti-inflammatory activity of all isolated compounds was evaluated using a lipopolysaccharide (LPS)-induced inflammation model in BV2 microglial cells. Meanwhile, these compounds exhibited activity in inhibiting NO production. Four compounds, capitalensis C (3), capitalensis D (4), 15-hydroxyl tricycloalternarene 5b (13) and guignarenone A (14) showed strong inhibitory effects with IC50 values of 21.6 ± 1.33, 12.2 ± 1.08, 18.6 ± 1.27, and 15.8 ± 1.20 µM, respectively. In addition, the structure-activity relationship of the anti-inflammatory activity of the compounds was discussed.


Assuntos
Sesquiterpenos , Ácido Chiquímico , Estrutura Molecular , Anti-Inflamatórios/química , Sesquiterpenos/química
6.
Food Chem ; 398: 133883, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35969995

RESUMO

Food safety is regarded as a crucial factor in both human health and economic progress. This study focuses on the fabrication of a label-free surface-enhanced Raman scattering (SERS) sensor for rapid sensing of three main mycotoxins (aflatoxin B1 (AFB1), ochratoxin A (OTA), ochratoxin B (OTB)) in rice using the optimized rough silver nanoparticles (AgNPs@K30) with enhancement factor (EF) 1.58 × 107 coupled multivariate calibration. Two variable selection chemometric calibration methods were comparatively applied. And genetic algorithm-partial least square achieved optimum correlation coefficient = 0.9797, 0.9779, and 0.9827, respectively for AFB1 ranging from 0.5 to 250 µg/Kg, for OTA and OTB 1 to 500 µg/Kg. The limit of detection (LOD) = 1.145, 1.133, and 1.180 µg/Kg, respectively, were determined according to principal component analysis-calibrated loading weight approach. And the great stability and reproducibility revealed the prepared SERS sensor has the potential to predict AFB1, OTA, and OTB in real rice samples.


Assuntos
Nanopartículas Metálicas , Micotoxinas , Oryza , Aflatoxina B1/análise , Calibragem , Humanos , Limite de Detecção , Micotoxinas/análise , Reprodutibilidade dos Testes , Prata , Análise Espectral Raman/métodos
7.
Anal Chim Acta ; 1206: 339787, 2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35473866

RESUMO

Cataluminescence sensor was useful for rapid determination of acetone in exhaled breath, which was a biomarker of diabetes. In Pt NPs@NU-901 nanocomposite, Pt NPs were dispersed in the elliptical structure of NU-901 successfully, and the original structure of NU-901 was kept intact. The CTL signal of acetone indicated that Pt NPs@NU-901 has the best catalytic performance. The introduction of Pt NPs improves the catalytic performance of nanocomposites effectively, and the coordination with acetone increased the adsorption energy by more than 8 times. Pt NPs@NU-901 integrated rapid capture, catalysis with detection of acetone, then the CTL method based on Pt NPs@NU-901 was established for rapid determination of acetone content in exhaled breath, the linear range was 0.50-70.0 mg/L, limit of detection was 0.23 mg/L (S/N = 3). RSDs for repeatability and reproducibility experiments were 4.8% and 4.5%, respectively. Acetone content in exhaled breath samples was detected by the method with recoveries from 90.6% to 107%. Notable, results of samples were consistent with that obtained from gas chromatography, indicating that the established CTL method was accurate, stable and rapid, and provided a guarantee for rapid and nondestructive screening of diabetic patients.


Assuntos
Diabetes Mellitus , Nanocompostos , Acetona/análise , Testes Respiratórios/métodos , Catálise , Diabetes Mellitus/diagnóstico , Humanos , Reprodutibilidade dos Testes
8.
J Clin Neurosci ; 102: 95-100, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35763987

RESUMO

This study identifies predictors of favourable intracranial venous collaterals and the effect of intracranial venous collaterals on outcomes and recanalization in patients with cerebral venous thrombosis (CVT). Data of 61 patients with CVT were retrospectively reviewed. Venous collateralization was defined as expanded cortical vein formation through different drainage pathways. Recanalization grades were classified into complete or partial recanalization based on images obtained during hospitalisation and follow-up. Independent predictors of collateral formation and poor prognosis were investigated via univariate and binary logistic regression analyses. The effects of different intracranial venous collaterals on recanalization in patients with CVT were assessed. A risk prediction nomogram for prognosis was constructed. Age ≤ 35 years (odds ratio (OR) = 7.067; 95% confidence interval (CI) = 1.776-28.277; P = 0.006) and male sex (OR = 5.490; 95% CI = 1.205-25.004; P = 0.028) were independent predictors of favourable venous collaterals. Venous collaterals were associated with early recanalization (P = 0.017) and not with long-term recanalization (P = 0.252). Male sex (OR = 0.047; 95% CI = 0.003-0.651; P = 0.023), subacute onset (OR = 0.026; 95% CI = 0.002-0.367; P = 0.007), and good collateral grade (OR = 0.168; 95% CI = 0.029-0.985; P = 0.048) were independent factors of favourable neurological outcomes at discharge. Haemorrhage on computed tomography at admission (OR = 10.868; 95% CI = 2.082-56.733; P = 0.005) was inversely correlated with prognosis. These findings suggested that male patients under 35 years of age are more likely to have favourable venous collaterals and good outcomes. Venous collaterals are significantly associated with early recanalization. These findings highlight the importance of venous collateral evaluation in patients with CVT.


Assuntos
Veias Cerebrais , Trombose Intracraniana , Trombose Venosa , Adulto , Veias Cerebrais/diagnóstico por imagem , Humanos , Trombose Intracraniana/complicações , Trombose Intracraniana/diagnóstico por imagem , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Trombose Venosa/diagnóstico por imagem
9.
Talanta ; 214: 120864, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32278408

RESUMO

In this work, Fe3O4/N co-doped hollow carbon spheres (Fe3O4@NHCS) as a promising electrocatalysis material had been prepared through carbonizing covalent organic frameworks and ferric irons. The morphology, structure, composition and electrocatalytic performance of Fe3O4@NHCS were characterized by various techniques. The electrode modified with Fe3O4@NHCS (Fe3O4@NHCS/GCE) exhibited excellent electrocatalytic activity for the oxidation of dopamine, uric acid, guanine and adenine. Simultaneous determination of these biomolecules was successfully achieved with Fe3O4@NHCS/GCE. Under the optimum conditions, the linear ranges for the determination of dopamine, uric acid, guanine and adenine were 0.01-40, 0.10-40, 0.50-30 and 0.50-40 µmol/L with the correlation coefficients of 0.9905, 0.9906, 0.9919 and 0.9908, respectively. The detection limits were 6.3, 36.1, 143.2 and 123.5 nmol/L for dopamine, uric acid, guanine and adenine, respectively (S/N = 3). In addition, the modified electrode was also applied to the simultaneous determination of these biomolecules in human serum samples and the recovery were varied from 97.6% to 104.2%. The results demonstrated that the Fe3O4@NHCS modified electrode had the characteristics of high sensitivity, good selectivity and reliability.


Assuntos
Adenina/sangue , Dopamina/sangue , Guanina/sangue , Estruturas Metalorgânicas/química , Ácido Úrico/sangue , Técnicas Biossensoriais , Carbono/química , Técnicas Eletroquímicas , Eletrodos , Compostos Férricos/química , Humanos , Nanosferas/química , Tamanho da Partícula , Propriedades de Superfície
10.
Talanta ; 188: 81-90, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30029450

RESUMO

In this paper, Fe3O4-doped nanoporous carbon (Fe3O4-NC) was synthesized through the carbonization of Fe-porous coordination polymer (Fe-PCP), which are also known as metal-organic framework (MOF), and fabricated into an electrochemical sensor for simultaneous analysis of diethylstilbestrol (DES) and 17ß-estradiol (E2) in toner. Fe3O4-NC was characterized by scanning electron microscope (SEM), powder X-ray diffraction (pXRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, N2 adsorption-desorption and so on. It is of great practical significance to achieve the simultaneous determination of the two estrogens because estrogens are co-existing in many real samples. The simultaneous determination of two common estrogens, DES and E2, was achieved through electro-catalytically oxidization at a Fe3O4-NC modified glassy carbon electrode (Fe3O4-NC/GCE). The peak currents of DES and E2 increased linearly as their concentrations increasing from 0.01 to 12 µmol/L and from 0.01 to 20 µmol/L, with detection limits of 4.6 nmol/L and 4.9 nmol/L (S/N = 3), respectively. This work was focused on the simultaneous determination of the two estrogens in toner. Furthermore, the recoveries of DES and E2 were 91.2-110%, in actual toner samples. The experimental results manifest that the sensor with a stronger anti-interference ability can be used for the simultaneous detection of DES and E2 in the actual toner sample.


Assuntos
Carbono/química , Dietilestilbestrol/análise , Técnicas Eletroquímicas/métodos , Estradiol/análise , Estrogênios/análise , Óxido Ferroso-Férrico/química , Adsorção , Eletrodos , Tinta , Limite de Detecção , Estruturas Metalorgânicas/química , Nanoporos , Porosidade , Reprodutibilidade dos Testes
11.
Biosens Bioelectron ; 112: 23-30, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-29689501

RESUMO

In this study, a facile solution approach was developed for the synthesis of a series of core-shell structured Ag@Cu2O nanocrystals of various shapes including triangles, spheres, and cubes with well-defined stable heterojunctions. The electrooxidation of dopamine (DA), uric acid (UA), guanine (G), and adenine (A) using these hybrids revealed morphology-dependent sensing properties, with activities and accumulation ability following the order, triangular Ag@Cu2O > spherical Ag@Cu2O > cubic Ag@Cu2O. Further, we constructed a novel graphene oxide (GO) nanosheet-reinforced triangular Ag@Cu2O ternary hetero-nanostructure. Such a hybrid with a three-dimensional interconnected hierarchical architecture is suitable for catalysis, since it not only leads to improved interfacial electron transfer, but also readily exposes the highly catalytic Ag@Cu2O to the reactants. Therefore, more enhanced electrochemical activities were observed for the oxidation of DA, UA, G, and A. This study provides an efficient way to synthesize morphology-controlled Ag@Cu2O heterogeneous catalysts for the fabrication of potential biosensors, and also opens up attractive avenues in the design of multifunctional ternary noble metal-semiconductor-carbon hybrids.


Assuntos
Adenina/isolamento & purificação , Técnicas Biossensoriais , Dopamina/isolamento & purificação , Guanina/isolamento & purificação , Ácido Úrico/isolamento & purificação , Adenina/química , Catálise , Cobre/química , Dopamina/química , Ouro/química , Grafite/química , Guanina/química , Nanoestruturas/química , Oxirredução , Ácido Úrico/química
12.
J Hazard Mater ; 302: 188-197, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26476305

RESUMO

A template-activated strategy was developed to construct core/shell structured carbon sphere@silver composite based on one-pot hydrothermal treatment. The CS@Ag possessed a uniform three-dimensional interconnected microstructure with an enlarged surface area and catalytic activity, which was further mechanically protected by graphene oxide (GO) nanolayers to fabricate intriguing configuration, which was beneficial for efficiently preventing the aggregation and oxidation of AgNPs and improving the electrical conductivity through intimate contact. By immobilizing this special material on electrode surface, the CS@Ag@GO was further used for sensitive determination of chlorinated phenols including 2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol. The tailored structure, fast electron transfer ability and facile preparation of CS@Ag@GO made it a promising electrode material for practical applications in phenols sensing.

13.
Food Chem ; 190: 544-551, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26213008

RESUMO

In this paper, we report a facile route to synthesize yolk-shell structured copper oxide@silica oxide (CuO@SiO2) spheres and their application to construct an electrochemical Formoterol fumarate (FF) sensor. The CuO@SiO2 was characterized by means of Fourier transform infrared spectroscopy, X-ray powder diffraction, Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy. Further, FF was electrocatalytically oxidized at the CuO@SiO2 film modified glassy carbon electrode (GCE), which led to a sensitive determination of FF. The oxidation current of FF was linear with concentration in the range of 0.030-10 µM and the detection limit was found to be 5.0 nM (S/N = 3). The observed analytical parameters such as wide linear range, low detection limit and short response time were superior to previously reported FF sensors. Finally, it was demonstrated that the proposed sensor could be used for the selective determination of FF present in swine feed and tissues.


Assuntos
Cobre/química , Fumarato de Formoterol/química , Microscopia Eletrônica de Transmissão/métodos , Dióxido de Silício/química , Animais , Suínos
14.
Talanta ; 121: 187-93, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24607125

RESUMO

A simple and novel electrochemical sensor for the determination of tetracycline (TC), a kind of antibiotic that may induce residue in the food chain, was developed by the modification of iron/zinc cation-exchanged montmorillonite (Fe/Zn-MMT) catalyst on glassy carbon electrode (GCE). The morphology and the structure of the Fe/Zn-MMT nanomaterial were characterized by scanning electron microscopy and X-ray diffraction, respectively. The results of electrochemical experiments demonstrated that the sensor exhibited excellent electrocatalytic activity to the oxidation of TC in the presence of sodium dodecyl sulfate. The sensor displayed a wide linear range from 0.30 to 52.0 µM and a low detection limit of 0.10 µM by using the derivative differential pulse voltammetry. Moreover, the electrochemical sensor was applied to the detection of TC in feedstuff and meat samples.


Assuntos
Bentonita/química , Técnicas Eletroquímicas/instrumentação , Ferro/química , Tetraciclinas/química , Zinco/química , Catálise , Cátions , Microscopia Eletrônica de Varredura , Difração de Raios X
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