Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 122
Filtrar
1.
Anal Chem ; 96(19): 7772-7779, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38698542

RESUMO

There is growing attention focused toward the problems of ecological sustainability and food safety raised from the abuse of herbicides, which underscores the need for the development of a portable and reliable sensor for simple, rapid, and user-friendly on-site analysis of herbicide residues. Herein, a novel multifunctional hydrogel composite is explored to serve as a portable and flexible sensor for the facile and efficient analysis of atrazine (ATZ) residues. The hydrogel electrode is fabricated by doping graphite-phase carbon nitride (g-C3N4) into the aramid nanofiber reinforced poly(vinyl alcohol) hydrogel via a simple solution-casting procedure. Benefiting from the excellent electroactivity and large specific surface area of the solid nanoscale component, the prepared hydrogel sensor is capable of simple, rapid, and sensitive detection of ATZ with a detection limit down to 0.002 ng/mL and per test time less than 1 min. After combination with a smartphone-controlled portable electrochemical analyzer, the flexible sensor exhibited satisfactory analytical performance for the ATZ assay. We further demonstrated the applications of the sensor in the evaluation of the ATZ residues in real water and soil samples as well as the user-friendly on-site point-of-need detection of ATZ residues on various agricultural products. We envision that this flexible and portable sensor will open a new avenue on the development of next-generation analytical tools for herbicide monitoring in the environment and agricultural products.


Assuntos
Atrazina , Técnicas Eletroquímicas , Herbicidas , Hidrogéis , Atrazina/análise , Herbicidas/análise , Hidrogéis/química , Técnicas Eletroquímicas/instrumentação , Grafite/química , Eletrodos , Limite de Detecção , Nitrilas/química , Nitrilas/análise , Nanofibras/química , Poluentes Químicos da Água/análise
2.
Opt Express ; 32(7): 12839-12851, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571095

RESUMO

In order to achieve the tunable unidirectional reflection amplification in a uniform atomic medium that is of vital importance to design high-quality nonreciprocal photonic devices, we propose a coherent closed three-level Δ-type atomic system by applying a microwave field, and a strong coupling field of linear variation along the x direction to control a probe field. In our scheme, the linearly increased coupling field destroys the spatial symmetry of probe susceptibility and effectively suppresses the reflection of one side; the microwave field constructs closed loop transitions to amplify the probe field and causes phase changes. The numerical simulation indicates that the unidirectional reflection amplification is sensitive to the relative phase ϕ and the coupling detuning Δc. Our results will open a new route toward harnessing optical non-reciprocity, which can provide more convenience and possibilities in the experimental realization.

3.
Phys Rev Lett ; 133(11): 116303, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39331964

RESUMO

In isolated nonlinear optical waveguide arrays, simultaneous conservation of longitudinal momentum flow ("internal energy") and optical power ("particle number") of the optical modes enables study of coupled thermal and particle transport in the negative temperature regime. Based on exact numerical simulation and rationale from Landauer formalism, we predict generic photonic version of the Wiedemann-Franz law in such systems, with the Lorenz number L∝|T|^{-2}. This is rooted in the spectral decoupling of thermal and particle current, and their different temperature dependence. In addition, in asymmetric junctions, relaxation of the system toward equilibrium shows apparent asymmetry for positive and negative biases, indicating rectification behavior. This Letter illustrates the possibility of simulate nonequilibrium transport processes using optical networks, in parameter regimes difficult to reach in natural condensed matter or atomic gas systems. It also provides new insights in manipulating power and momentum flow of optical waves in artificial waveguide arrays.

4.
Opt Express ; 31(23): 38228-38239, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017934

RESUMO

Control of unidirectional light propagation is of paramount importantance to optical signal processing and optical communication. Especially, the amplified optical signal can isolate noise well that may provide more applications. In this work, we propose a dynamically modulated regime to realize unidirectional reflection amplification in a short and dense uniform atomic medium, and all atoms are driven into four-level double-Λ type by two coupling fields with linearly varied intensities along x direction and two weak probe fields. Based on four-wave mixing resonance and the broken spatial symmetry, the complete nonreciprocal reflection (unidirectional reflection) can be amplified with reflectivity more than 2.0, even to 6.0. In addition, the width, height, and position of the unidirectional reflection bands can be tunable. Thus, our regime is feasible and may inspire further applications in all-optical networks that require controllable unidirectional light amplification.

5.
Opt Express ; 31(9): 14694-14704, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37157328

RESUMO

Non-reciprocal reflections of optical signals are unusual yet fascinating to achieve the imminent applications of non-reciprocal photonic devices and circuits. The complete non-reciprocal reflection (unidirectional reflection) was recently found to be achievable in a homogeneous medium, if the real and imaginary parts of the probe susceptibility satisfy the spatial Kramers-Kronig (KK) relation. We propose a coherent four-level tripod model for realizing dynamically tunable two-color non-reciprocal reflections by applying two control fields with linearly modulated intensities. We found that, the unidirectional reflection can be obtained if the non-reciprocal frequency regions are located in the electromagnetically induced transparency (EIT) windows. This mechanism is to break the spatial symmetry by the spatial modulation of susceptibility to induce unidirectional reflections, the real and imaginary parts of the probe susceptibility are no longer required to satisfy the spatial KK relation.

6.
J Sep Sci ; 46(10): e2201012, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36919915

RESUMO

A previously developed high-performance liquid chromatography method combined with pulsed amperometric detection allowed to separate many impurities of paromomycin. However, due to the presence of ion pairing agents and sodium hydroxide in the mobile phase, direct coupling to mass spectrometry for the identification of the chemical structures of the impurities was not an option. Indeed, ion suppression was encountered by trifluoroacetic acid and pentafluoroproponic acid in the mobile phase. A cation self-regenerating suppressor, which was originally designed for increasing analyte conductivity of ammonia and amines analysis in ion chromatography, was coupled between the liquid chromatography and ion trap-time of flight-mass spectrometry and almost all trifluoroacetic acid and pentafluoroproponic acid in the mobile phase was removed. The limit of detection of paromomycin in this integrated system improved significantly to 20 ng/ml (0.4 ng). The chemical structures of 19 impurities were elucidated and seven impurities were reported for the first time.

7.
Eur Arch Otorhinolaryngol ; 280(9): 4131-4140, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37160465

RESUMO

PURPOSE: Accurate histologic grade assessment is helpful for clinical decision making and prognostic assessment of sinonasal squamous cell carcinoma (SNSCC). This research aimed to explore whether whole-tumor histogram analysis of apparent diffusion coefficient (ADC) maps with machine learning algorithms can predict histologic grade of SNSCC. METHODS: One hundred and forty-seven patients with pathologically diagnosed SNSCC formed this retrospective study. Sixty-six patients were low-grade (grade I/II) and eighty-one patients were high-grade (grade III). Eighteen histogram features were obtained from quantitative ADC maps. Additionally, the mean ADC value and clinical features were analyzed for comparison with histogram features. Machine learning algorithms were applied to build the best diagnostic model for predicting histological grade. The receiver operating characteristic (ROC) curve was used to evaluate the performance of each model prediction, and the area under the ROC curve (AUC) were analyzed. RESULTS: The histogram model based on three features (10th Percentile, Mean, and 90th Percentile) with support vector machine (SVM) classifier demonstrated excellent diagnostic performance, with an AUC of 0.947 on the testing dataset. The AUC of the histogram model was similar to that of the mean ADC value model (0.947 vs 0.957; P = 0.7029). The poor diagnostic performance of the clinical model (AUC = 0.692) was improved by the combined model incorporating histogram features or mean ADC value (P < 0.05). CONCLUSION: ADC histogram analysis improved the projection of SNSCC histologic grade, compared with clinical model. The complex histogram model had comparable but not better performance than mean ADC value model.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias dos Seios Paranasais , Humanos , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Curva ROC , Neoplasias dos Seios Paranasais/diagnóstico por imagem , Algoritmos , Sensibilidade e Especificidade
8.
J Environ Manage ; 347: 119093, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37783080

RESUMO

Eutrophic lakes are a major source of the atmospheric greenhouse gas methane (CH4), and CH4 ebullition emissions from inland lakes have important implications for the carbon cycle. However, the spatio-temporal heterogeneity of CH4 ebullition emission and its influencing factors in shallow eutrophic lakes of arid and semi-arid regions remain unclear. This study aimed to determine the mechanism of CH4 emission via eutrophication in Lake Ulansuhai, a large shallow eutrophic lake in a semi-arid region of China.To this end, monthly field surveys were conducted from May to October 2021, and gas chromatography was applied using the headspace equilibrium technique with an inverted funnel arrangement. The total CH4 fluxes ranged from 0.102 mmol m-2 d-1 to 59.296 mmol m-2 d-1 with an average value of 4.984 ± 1.82 mmol m-2 d-1. CH4 ebullition emissions showed significant temporal and spatial variations. The highest CH4 ebullition emission was observed in July with a grand mean of 9.299 mmol m-2 d-1, and the lowest CH4 ebullition emissions occurred in October with an average of 0.235 mmol m-2 d-1. Among seven sites (S1-S7), the maximum (3.657 mmol m-2 d-1) and minimum (1.297 mmol m-2 d-1). CH4 ebullition emissions were observed at S2 and S7, respectively. As the main route of CH4 emission to the atmosphere in Lake Ulansuhai, the CH4 ebullition flux during May to October accounted for 69% of the total CH4 flux. Statistical analysis showed that CH4 ebullition was positively correlated with temperature (R = 0.391, P < 0.01) and negatively correlated with air pressure (R = 0.286, P < 0.00). Temperature and air pressure were found to strongly regulate the production and oxidation of CH4. Moreover, nutritional status indicators such as TP and NH4+-N significantly affect CH4 ebullition emissions (R = 0.232, P < 0.01; R = -0.241, P < 0.01). This study reveals the influencing factors of CH4 ebullition emission in Lake Ulansuhai, and provides theoretical reference and data support for carbon emission from eutrophic lakes. Nevertheless, research on eutrophic shallow lakes needs to be further strengthened. Future research should incorporate improved flux measurement techniques with process-based models to improve the accuracy from regional to large-scale estimation of CH4 emissions and clarify the carbon budget of aquatic ecosystems. In this manner, the understanding and predictability of CH4 ebullition emission from shallow lakes can be improved.


Assuntos
Lagos , Metano , Metano/análise , Ecossistema , China , Carbono/análise
9.
Molecules ; 28(21)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37959866

RESUMO

The processing of tea leaves plays a crucial role in the formation of the taste of the resulting tea. In order to study the compositions of and changes in taste-related substances during the processing of Rizhao green tea, non-targeted metabolomics was used, based on UHPLC-Q Exactive MS. Totals of 529, 349, and 206 non-volatile metabolites were identified using three different detection modes, of which 112 secondary metabolites were significantly changed. Significant variations in secondary metabolites were observed during processing, especially during the drying stage, and the conversion intensity levels of non-volatile metabolites were consistent with the law of "Drying > Fixation > Rolling". The DOT method was used to screen tea-quality-related compounds that contributed significantly to the taste of Rizhao green tea, including (-)-epicatechin gallate, (-)-epicatechin gallate, gallic acid, L-theanine, and L-leucine, which make important contributions to taste profiles, such as umami and bitterness. Metabolic pathway analysis revealed that purine metabolism, caffeine metabolism, and tyrosine metabolism perform key roles in the processing of Rizhao green tea in different processing stages. The results of this study provide a theoretical basis for tea processing and practical advice for the food industry.


Assuntos
Camellia sinensis , Chá , Chá/metabolismo , Cafeína/análise , Paladar , Percepção Gustatória , Metabolômica/métodos , Camellia sinensis/metabolismo
10.
Anal Bioanal Chem ; 414(22): 6497-6506, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35829769

RESUMO

The multiclass determination of antibiotic residues in the soil is challenging because of its complex physicochemical properties. In this study, a simple analytical method was developed to simultaneously extract and determine 58 antibiotics from the soil. A novel acidity-regulated extraction-partition-concentration protocol was established for the simultaneous extraction of five classes (23 sulfonamides, 18 quinolones, five tetracyclines, eight macrolides, and four chloramphenicols) of antibiotics from the soil. Compared to traditional methods, the sample preparation efficiency was significantly improved by four times (45 min vs. 230 min) by optimizing the extraction method and omitting the time-consuming solid-phase extraction (SPE) procedure. The ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was optimized to determine the 58 antibiotics in a single run by applying positive/negative switching acquisition mode in less than 10 min with the baseline separation of sulfameter and sulfamethoxypyridazine. Suitable recoveries, ranging between 60 and 120%, were obtained for most antibiotics, with RSD <20%. The limits of quantification (LOQ) of the method were 2 µg/kg and 5 µg/kg. Thus, this study provides a simple, reliable, and economical method for accurately and rapidly determining a multiclass of antibiotics in the soil.


Assuntos
Macrolídeos , Quinolonas , Antibacterianos/análise , Cloranfenicol/análise , Cromatografia Líquida de Alta Pressão , Macrolídeos/análise , Quinolonas/análise , Solo/química , Extração em Fase Sólida/métodos , Sulfonamidas/análise , Espectrometria de Massas em Tandem/métodos , Tetraciclina , Tetraciclinas/análise
11.
J Comput Assist Tomogr ; 46(5): 830-835, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35675691

RESUMO

OBJECTIVE: The aim of the study was to explore the value of T2-sampling perfection with application-optimized contrasts by using different flip angle evolutions (T2-SPACE) in identifying space-occupying lesions of the inner ear. METHODS: We collected the T2-SPACE and 3-dimensional inversion-recovery sequence with real reconstruction (3D-real IR) images of 220 patients with inner ear symptoms, including 15 patients with inner ear space-occupying lesions. With T2-SPACE images hidden, a senior and junior radiologist made a diagnosis for all patients using only the 3D-real IR images. After 4 weeks the images were shuffled, and T2-SPACE images were made available to the 2 radiologists in addition to 3D-real IR to reconsider the diagnosis for all patients. RESULTS: With the SPACE images hidden, the correct diagnosis rate of the space-occupying lesions was 8/15 (53.3%) for the senior radiologist, whereas it was only 2/15 (13.3%) for the junior radiologist. Without the SPACE images hidden, the correct diagnosis rate of the space-occupying lesions was 15/15 (100.0%) for the senior radiologist, whereas it was 13/15 (86.7%) for the junior radiologist. Of the 15 patients, 7 had only vestibular space-occupying lesions, 2 had only cochlear space-occupying lesions, and 6 had both. No semicircular canal space-occupying lesion was observed. CONCLUSIONS: T2-SPACE can help identify space-occupying lesions of the inner ear that tend to be misdiagnosed as endolymphatic hydrops on 3D-real IR. The senior radiologist had a higher rate for the identification of space-occupying lesions than the junior radiologist when using only 3D-real IR, although the senior radiologist detection rate was still only 53.3%. With the addition of T2-SPACE, both the junior and senior radiologist achieved a high detection rate, which increased to 86.7% and 100%, respectively.


Assuntos
Orelha Interna , Hidropisia Endolinfática , Erros de Diagnóstico , Orelha Interna/diagnóstico por imagem , Orelha Interna/patologia , Hidropisia Endolinfática/diagnóstico por imagem , Hidropisia Endolinfática/patologia , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Perilinfa
12.
J Sep Sci ; 45(10): 1806-1817, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35261148

RESUMO

Acephate is widely used in crops as racemate. However, the enantioselective dissipation of acephate enantiomers has not been investigated in pakchoi. A sensitive and effective approach was established for determining residues of acephate and its highly toxic metabolite methamidophos enantiomers by supercritical fluid chromatography tandem mass spectrometry. Baseline separations for their enantiomers were achieved by using a Chiralcel OD-H column. The optimal chromatographic conditions were obtained as follows: CO2 /ethanol (95/5) as mobile phase; flow rate, 3.0 mL/min; column temperature, 40°C. The mean recoveries (RSDs) of analytes were in the range of 77-83.1% (6.1-9.9%), 75.4-87.5% (9.3-13.2%), and 81.5-84.2% (7.1-13.4%) at three fortification levels (0.005, 0.05, and 0.5 mg/kg for each enantiomer) for interday assay (n = 18). The method was used to evaluate the enantioselective dissipation of acephate and methamidophos in pakchoi. S-acephate dissipated faster than R-acephate, while the concentration of R-methamidophos was higher than that of S-methamidophos during the entire study period. The results indicated that the R-enantiomer of acephate and methamidophos was preferentially enriched in pakchoi. The established analysis approach and the study data provided useful information for the rational use of acephate in agriculture.


Assuntos
Cromatografia com Fluido Supercrítico , Inseticidas , Inseticidas/análise , Compostos Organotiofosforados , Fosforamidas , Estereoisomerismo , Espectrometria de Massas em Tandem/métodos
13.
BMC Med Imaging ; 22(1): 132, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35883055

RESUMO

BACKGROUND: Diffusion-weighted imaging (DWI) has become an important tool for the detection of cholesteatoma. The purpose of this study was to explore the value of 2D BLADE turbo gradient- and spin-echo imaging (TGSE BLADE) DWI in the quantitative diagnosis of recurrent temporal bone cholesteatoma (CS). METHODS: From March 2018 to October 2021, 67 patients with suspected recurrence of temporal bone CS after assessment by clinical otorhinolaryngologists who had undergone previous ear surgery for CS were prospectively evaluated by magnetic resonance imaging (MRI). Two radiologist assessed images independently. Quantitative parameters such as signal intensity ratio (SIR) calculated using, as a reference, the inferior temporal cortex (SIRT) and the background noise (SIRN), apparent diffusion coefficient (ADC) value, and ADC ratio (with pons as reference) measured on TGSE BLADE sequences were assessed. Using receiver operating characteristic (ROC) curve analysis, the optimal threshold and diagnostic performance for diagnosing recurrent CS were determined. Pair-wise comparison of the ROC curves was performed using the area under the ROC curve (AUC). RESULTS: Finally, 44 patients were included in this study, including 25 CS and 19 non-cholesteatoma (NCS). Mean SIRT and mean SIRN on TGSE BLADE DWI were significantly higher for CS than NCS lesions (p < 0.001). Meanwhile, mean ADC values and mean ADC ratios on ADC maps were significantly lower in the CS group than in the NCS group (p < 0.001). According to ROC analysis, the diagnostic efficacy of quantitative parameters such as SIRT (AUC = 0.967), SIRN (AUC = 0.979), ADC value (AUC = 1.0), and ADC ratio (AUC = 0.983) was significantly better than that of qualitative DWI (AUC = 0.867; p = 0.007, 0.009, 0.011 and 0.037, respectively). CONCLUSIONS: Residual/recurrent temporal bone CS can be accurately detected using quantitative evaluation of TGSE BLADE DWI.


Assuntos
Imagem de Difusão por Ressonância Magnética , Humanos , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética , Curva ROC , Sensibilidade e Especificidade , Osso Temporal/diagnóstico por imagem
14.
Acta Radiol ; 63(10): 1381-1389, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34528834

RESUMO

BACKGROUND: A two-dimensional turbo gradient-echo and spin-echo diffusion-weighted pulse sequence with a non-Cartesian BLADE trajectory (TGSE BLADE) can eliminate image artifacts and distortion with clinically acceptable scan times. This process has the potential to overcome the shortcomings of current diffusion-weighted imaging (DWI) techniques, especially in the sinonasal region. PURPOSE: To investigate the feasibility of TGSE BLADE in the assessment of sinonasal lesions and compare the quality of TGSE BLADE with RESOLVE images both qualitatively and quantitatively. MATERIAL AND METHODS: A total of 36 patients with sinonasal lesions were included in this prospective study. DW images acquired using TGSE BLADE and RESOLVE were performed with the same acquisition time. Two independent observers evaluated the qualitative parameters (overall image quality, lesion visibility, and geometric distortion) and quantitative parameters (geometric distortion ratio [GDR], signal-to-noise ratio [SNR], contrast, contrast-to-noise ratio [CNR], and apparent diffusion coefficient [ADC] value) of the two sequences. RESULTS: Qualitative assessment revealed that TGSE BLADE exhibited higher overall image quality (P < 0.001) and lesion visibility (P < 0.001) and less geometric distortion (P < 0.001) than RESOLVE. Quantitative assessment showed that TGSE BLADE images exhibited higher contrast (P < 0.001) and CNR (P < 0.001) and lower GDR (P < 0.05) and SNR (P < 0.001) than RESOLVE images. The ADC value of TGSE BLADE was significantly lower than that of RESOLVE (P < 0.05). CONCLUSION: TGSE BLADE can reduce susceptibility artifacts and geometric distortion more than RESOLVE and appears to be a promising diffusion imaging sequence for the assessment of sinonasal lesions.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imagem Ecoplanar , Artefatos , Imagem de Difusão por Ressonância Magnética/métodos , Imagem Ecoplanar/métodos , Humanos , Estudos Prospectivos , Reprodutibilidade dos Testes , Razão Sinal-Ruído
15.
Molecules ; 27(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36431783

RESUMO

The purpose of this study is to explore the effects of pine pollen polysaccharides and sulfated polysaccharides on mice with ulcerative colitis and whether they could protect mice from inflammation by regulating the tight junctions of colonic epithelial cells and regulating the RIPK3-dependent necroptosis pathways. Pine pollen polysaccharides were prepared by water boiling and ethanol precipitation. After deproteinedization with trichloroacetic acid, the UV spectrum showed that there were no proteins. One polysaccharide component (PPM60-III) was made by gel filtration chromatography, and then sulfated polysaccharide (SPPM60-III) was derived using the chlorosulfonic acid-pyridine method. After treatment with PPM60-III and SPPM60-III, the body weight of mice with ulcerative colitis induced by dextran sodium sulfate increased, the DAI score decreased, the levels of pro-inflammatory factors and inflammation-related enzymes decreased, and the level of anti-inflammatory factors increased. In addition, after treatment, the expressions levels of tight junction proteins increased, the expressions levels of key proteins of programmed necroptosis decreased, while the level of Caspase-8 increased. The results indicated that pine pollen polysaccharides and sulfated polysaccharides have a certain therapeutic effect on UC mice, and the therapeutic effect may be achieved by regulating the tight junction of colonic epithelial cells and regulating the RIPK3-dependent necroptosis pathways.


Assuntos
Colite Ulcerativa , Necroptose , Camundongos , Animais , Junções Íntimas , Sulfatos/análise , Sulfato de Dextrana/efeitos adversos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Polissacarídeos/química , Óxidos de Enxofre , Inflamação , Pólen/química , Proteína Serina-Treonina Quinases de Interação com Receptores
16.
J Sci Food Agric ; 102(12): 5288-5300, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35306664

RESUMO

BACKGROUND: As a lipid-soluble vitamin necessary for normal human physiology, vitamin D is mostly used in fortified foods, medicines and adjuvant treatment of diseases. However, taken in high doses, vitamin D can be toxic. METHODS: We treated RAW264.7 cells with a semi-inhibitory concentration (IC50 ) of vitamin D3 . The metabolic changes in the treated cells were analyzed by 1 H nuclear magnetic resonance (NMR) and ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). RESULTS: After treatment of RAW264.7 cells with an IC50 dose of 55 µm vitamin D3 , tunor necrosis factor-α levels decreased significantly and remarkable metabolic differences were also observed, with 12 types of metabolites were identified by 1 H NMR and 87 identified by UPLC-MS/MS. Moreover, the metabolism of amino acids, sugars, lipids and other metabolic pathways were also affected. CONCLUSION: Although vitamin D3 is an indispensable nutrient in the body, excessive exposure has negative effects on cells and their metabolism. The present study will assist further analyses of the mechanism underlying vitamin D3 toxicity. © 2022 Society of Chemical Industry.


Assuntos
Colecalciferol , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Humanos , Espectroscopia de Ressonância Magnética , Metabolômica/métodos , Espectrometria de Massas em Tandem/métodos , Vitamina D , Vitaminas/análise
17.
Clin Otolaryngol ; 47(6): 717-723, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35034431

RESUMO

OBJECTIVES: Three-dimensional inversion-recovery sequence with real reconstruction (3D-real IR) magnetic resonance imaging (MRI) can detect endolymphatic hydrops of the inner ear. We aimed to explore a appropriate dose for intravenous gadolinium injection. DESIGN: Observational prospective study. SETTING: Tertiary referral centre. PARTICIPANTS: We collected 90 unilateral definite Meniere's disease patients. MAIN OUTCOME MEASURES: All enrolled patients were divided into three groups randomly (patients in group A, B and C received gadolinium injection in 1/1.5/2 times doses respectively). After 4 h, inner ear MRI scans were applied. RESULTS: The signal intensities of B-affected ears and C-affected ears were significantly higher than A-affected ears (p < .05); however, no difference was found between B-affected ears and C-affected ears (p = .267). The same conditions also appeared in the three unaffected-ear groups. Moreover, the signal intensities of affected-ear in group A, B and C were significantly higher than that of the corresponding unaffected-ear groups (p < .05). Besides, the subjective visual evaluation scores of group B and C were significantly better than that of group A (p < .05). CONCLUSIONS: Intravenous injection of gadolinium in a single dose may be unbefitting for the inner ear imaging based on 3D-real IR MRI, both the applications of gadolinium in 1.5 times and double doses can have a good perilymphatic enhancement effect of inner ear. In order to minimise the use of dose for avoiding or mitigating the adverse reactions and renal damage, 1.5 times dose may be preferred in clinical practice.


Assuntos
Orelha Interna , Doença de Meniere , Meios de Contraste , Orelha Interna/diagnóstico por imagem , Gadolínio , Gadolínio DTPA , Humanos , Injeções Intravenosas , Imageamento por Ressonância Magnética/métodos , Doença de Meniere/diagnóstico por imagem , Estudos Prospectivos
18.
Exp Brain Res ; 239(2): 401-412, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33206235

RESUMO

Delta-opioid receptor (DOR) is widely distributed in the central nervous system, and its activation protects against ischaemic/hypoxic brain injury. However, the role of DOR in microglia in ischaemic stroke has not yet been fully investigated. We found that DOR was expressed in both human and mouse cerebral microglia, besides, it was upregulated in activated BV2 microglial cells by immunofluorescence staining and Western blot. DOR activation by the specific agonist TAN-67 significantly enhanced BV2 microglial cell viability and reduced apoptosis, as evidenced by decreased cleaved caspase-3 levels and TdT-mediated aUTP-X nick end labelling (TUNEL) staining after LPS stimulation. Furthermore, activation of DOR significantly inhibited inducible nitric oxide synthase (iNOS) production and dose-dependently inhibited the mRNA and protein expression levels of other pro-inflammatory cytokines, including IL-1ß and IL-6, whereas it increased the expression of the anti-inflammatory cytokine IL-10 in LPS-stimulated BV2 microglial cells; these effects were correlated with diminished phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38. Moreover, these effects could be reversed by the DOR antagonist naltrindole. DOR activation can activate microglia to switch to the beneficial phenotype and inhibit LPS-induced inflammation and apoptosis via the mitogen-activated protein kinase (MAPK)/caspase-3 pathway in BV2 microglial cells. This study provides new insight into neuroprotection against and treatment of ischaemic stroke.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Analgésicos Opioides , Animais , Apoptose , Caspase 3 , Caspases , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Lipopolissacarídeos/toxicidade , Camundongos , Microglia , Óxido Nítrico , Receptores Opioides
19.
Phytother Res ; 35(4): 2057-2073, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33210367

RESUMO

Pinus yunnanensis pollen is rich in various physiological functions. However, whether the pine pollen wall (PW) plays a beneficial role in the body has not been studied. In this work, we have analyzed its effects on the metabolism and gut microbiota of mouse models of dyslipidemia. We found that the intake of pine PW prevents the liver pathologic changes and reduce the concentrations of TNF-α, IL-6, TC, and high-density lipoprotein cholesterol. Moreover, it can regulate bile acid and fat metabolism, SCFAs content, and the structure of the gut microbiota. According to the change of carbohydrate metabolites, we speculated that cellulose should be the main component to play the above beneficial role, and sporopollenin cannot be utilized in the intestine. Therefore, we consider this study of great significance as it gives a description of biological effects of the pine PW and paves the road to its use in health products.


Assuntos
Biomarcadores , Dislipidemias , Microbioma Gastrointestinal , Pinus , Animais , Masculino , Camundongos , Biomarcadores/metabolismo , Dislipidemias/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Metabolismo dos Lipídeos , Pinus/química
20.
Am J Physiol Heart Circ Physiol ; 318(5): H1068-H1079, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32216615

RESUMO

The clinical risks and prognosis of diabetic vascular intimal calcification (VIC) and medial calcification (VMC) are different. This study aims to investigate the mechanism of VIC/VMC translocation. Anterior tibial arteries were collected from patients with diabetic foot amputation. The patients were then divided into VIC and VMC groups. There were plaques in all anterior tibial arteries, while the enrichment of galectin-3 in arterial plaques in the VIC group was significantly higher than that in the VMC group. Furthermore, a macrophage/vascular smooth muscle cell (VSMC) coculture system was constructed. VSMC-derived extracellular vesicles (EVs) was labeled with fluorescent probe. After macrophages were pretreated with recombinant galectin-3 protein, the migration of VSMC-derived EVs and VSMC-derived calcification was more pronounced. And anti-galectin-3 antibody can inhibit this process of EVs and calcification translocation. Then, lentivirus (LV)-treated bone marrow cells (BMCs) were transplanted into apolipoprotein E-deficient (ApoE-/-) mice, and a diabetic atherosclerosis mouse model was constructed. After 15 wk of high-fat diet, ApoE-/- mice transplanted with LV-shgalectin-3 BMCs exhibited medial calcification and a concentrated distribution of EVs in the media. In conclusion, upregulation of galectin-3 in macrophages promotes the migration of VSMC-derived EVs to the intima and induces diabetic vascular intimal calcification.NEW & NOTEWORTHY The clinical risk and prognosis of vascular intimal and medial calcification are different. Macrophage galectin-3 regulates the migration of vascular smooth muscle cell-derived extracellular vesicles and mediates diabetic vascular intimal/medial calcification translocation. This study may provide insights into the early intervention in diabetic vascular calcification.


Assuntos
Angiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Galectina 3/metabolismo , Macrófagos/metabolismo , Túnica Íntima/metabolismo , Calcificação Vascular/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Apolipoproteínas E/genética , Células Cultivadas , Angiopatias Diabéticas/patologia , Cardiomiopatias Diabéticas/genética , Cardiomiopatias Diabéticas/patologia , Vesículas Extracelulares/metabolismo , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Miócitos de Músculo Liso/metabolismo , Artérias da Tíbia/metabolismo , Artérias da Tíbia/patologia , Túnica Íntima/patologia , Calcificação Vascular/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA