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1.
Opt Express ; 32(7): 11583-11599, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571002

RESUMEN

A multiple sub-pupil ultra-spectral imaging system designed with a single spectrometer and detector can simultaneously detect multiple-channel spectra with ultra-high spectral resolution. However, due to using a prism in the system's front end, the nonlinear dispersion introduces spectral line tilt in the imaging spectra. This phenomenon can lead to bias in the final spectral data. To eliminate this issue, we propose a new design by introducing a second prism to correct this spectral tilt in the system. The angle of spectral line tilt generated by the nonlinear dispersion of the first prism is derived. It provides the theoretical basis for characterizing the second complementary prism. Finally, a UV multiple sub-pupil ultra-spectral imaging system is designed. The system employs two pupil separation prisms and one flat panel array to segment the pupil in three channels, each operating within spectral ranges of 180∼210 nm, 275∼305 nm, and 370∼400 nm, respectively. The spectral resolutions in all three channels are better than 0.1 nm. The corrected spectral line tilt is less than 1/3 of a pixel in the two channels with pupil separation prisms. At a Nyquist frequency of 30 lp/mm, the modulation transfer functions of all three channels are greater than 0.7, ensuring imaging quality. The design results indicate that the method proposed in this paper, utilizing complementary prisms, can effectively correct the spectral line tilt caused by the nonlinear dispersion of the pupil separation prisms. This design approach can be a reference for developing multiple sub-pupil ultra-spectral imaging systems.

2.
Int J Mol Sci ; 24(2)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36675284

RESUMEN

The preparation of adsorbents with eco-friendly and high-efficiency characteristics is an important approach for pollutant removal, and can relieve the pressure of water shortage and environmental pollution. In recent studies, much attention has been paid to the potential of hydrothermal carbonization (HTC) from biomass, such as cellulose, hemicellulose, lignin, and agricultural waste for the preparation of adsorbents. Hereby, this paper summarizes the state of research on carbon adsorbents developed from various sources with HTC. The reaction mechanism of HTC, the different products, the modification of hydrochar to obtain activated carbon, and the treatment of heavy metal pollution and organic dyes from wastewater are reviewed. The maximum adsorption capacity of carbon from different biomass sources was also evaluated.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Biomasa , Colorantes , Celulosa , Adsorción , Temperatura
3.
J Cell Mol Med ; 22(3): 1489-1500, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29265525

RESUMEN

Exercise training (ET) is a safe and efficacious therapeutic approach for myocardial infarction (MI). Given the numerous benefits of exercise, exercise-induced mediators may be promising treatment targets for MI. C57BL/6 mice were fed 1-trifluoromethoxyphenyl-3-(1-propionylpiperidine-4-yl) urea (TPPU), a novel soluble epoxide hydrolase inhibitor (sEHI), to increase epoxyeicosatrienoic acid (EET) levels, for 1 week before undergoing MI surgery. After 1-week recovery, the mice followed a prescribed exercise programme. Bone marrow-derived endothelial progenitor cells (EPCs) were isolated from the mice after 4 weeks of exercise and cultured for 7 days. Angiogenesis around the ischaemic area, EPC functions, and the expression of microRNA-126 (miR-126) and its target gene Spred1 were measured. The results were confirmed in vitro by adding TPPU to EPC culture medium. ET significantly increased serum EET levels and promoted angiogenesis after MI. TPPU enhanced the effects of ET to reduce the infarct area and improve cardiac function after MI. ET increased EPC function and miR-126 expression, which were further enhanced by TPPU, while Spred1 expression was significantly down-regulated. Additionally, the protein kinase B/glycogen synthase kinase 3ß (AKT/GSK3ß) signalling pathway was activated after the administration of TPPU. EETs are a potential mediator of exercise-induced cardioprotection in mice after MI. TPPU enhances exercise-induced cardiac recovery in mice after MI by increasing EET levels and promoting angiogenesis around the ischaemic area.


Asunto(s)
Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Cardiotónicos/metabolismo , Inhibidores Enzimáticos/farmacología , Infarto del Miocardio/terapia , Neovascularización Fisiológica , Compuestos de Fenilurea/farmacología , Condicionamiento Físico Animal , Piperidinas/farmacología , Ácido 8,11,14-Eicosatrienoico/metabolismo , Ácido 8,11,14-Eicosatrienoico/farmacología , Proteínas Adaptadoras Transductoras de Señales , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Cardiotónicos/farmacología , Vasos Coronarios/cirugía , Modelos Animales de Enfermedad , Células Progenitoras Endoteliales/citología , Células Progenitoras Endoteliales/efectos de los fármacos , Células Progenitoras Endoteliales/metabolismo , Epóxido Hidrolasas/antagonistas & inhibidores , Epóxido Hidrolasas/genética , Epóxido Hidrolasas/metabolismo , Regulación de la Expresión Génica , Glucógeno Sintasa Quinasa 3 beta/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , MicroARNs/metabolismo , Infarto del Miocardio/genética , Infarto del Miocardio/metabolismo , Infarto del Miocardio/fisiopatología , Cultivo Primario de Células , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Transducción de Señal
4.
Artículo en Inglés | MEDLINE | ID: mdl-38757332

RESUMEN

INTRODUCTION: Quercetin (Qc), rutin (Ru), and hyperoside (Hyp) are three common polyphenols widely distributed in the plant kingdom. METHOD: This study explored the inhibition and mechanisms of Qc, Ru, and Hyp against xanthine oxidase (XOD) by enzyme kinetic analysis, fluorescence analysis, and molecular docking. The inhibitory activities of the three polyphenols on XOD showed the following trend: quercetin > hyperoside > rutin, with IC50 values of 8.327 ± 0.36 µmol/L, 35.215 ± 0.4 µmol/L and 60.811 ± 0.19 µmol/L, respectively. All three polyphenols inhibited xanthine oxidase activity in a mixed-competitive manner. Synchronous fluorescence results demonstrated that three polyphenols binding to XOD were spontaneous and showed static quenching. RESULT: The binding of the three polyphenols to XOD is mainly driven by hydrogen bonding and van der Waals forces, resulting in the formation of an XOD-XA complex with only one affinity binding site. The binding sites of the three RSFQ phenolic compounds are close to those of tryptophan. Molecular docking showed that all three polyphenols enter the active pocket of XOD and maintain the stability of the complex through hydrogen bonding, hydrophobic interaction, and van der Waals forces. CONCLUSION: The results provide a theoretical basis for quercetin, rutin, and hyperoside to be used as function factors to prevent hyperuricemia.

5.
Biomolecules ; 11(7)2021 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-34208902

RESUMEN

The vasculature of stem-cell-derived liver organoids can be engineered using methods that recapitulate embryonic liver development. Hepatic organoids with a vascular network offer great application prospects for drug screening, disease modeling, and therapeutics. However, the application of stem cell-derived organoids is hindered by insufficient vascularization and maturation. Here, we review different theories about the origin of hepatic cells and the morphogenesis of hepatic vessels to provide potential approaches for organoid generation. We also review the main protocols for generating vascularized liver organoids from stem cells and consider their potential and limitations in the generation of vascularized liver organoids.


Asunto(s)
Hígado/patología , Organoides/irrigación sanguínea , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular , Evaluación Preclínica de Medicamentos/métodos , Ingeniería Genética/métodos , Hepatocitos/patología , Humanos , Hígado/crecimiento & desarrollo , Organogénesis/fisiología , Organoides/crecimiento & desarrollo , Organoides/metabolismo , Células Madre/metabolismo
6.
World Neurosurg ; 147: 105-114, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33290896

RESUMEN

BACKGROUND: Surgery is the definitive treatment option for symptomatic Chiari malformation I (CMI), but there is no clear consensus as to the preferred surgical method. This study aimed to quantitatively assess and compare the effect and safety of dura splitting decompression (DSD) and posterior fossa decompression with duraplasty (PFDD) in treating patients with CMI. METHODS: A literature search of EMBASE, MEDLINE, PubMed, Cochrane Library, and Web of Science databases was conducted. References from January 1990 to September 2020 were retrieved. We only included papers containing original data, comparing the use of DSD and PFDD in CMI patients. RESULTS: Overall, 11 relevant studies were identified, wherein 443 patients treated for CMI by DSD were compared with 261 patients treated by PFDD. No difference was observed between PFDD and PFD in terms of clinical improvement (P = 0.69), syringomyelia improvement (P = 0.90), or reoperation (P = 0.22). DSD was associated with shorter operation durations (P = 0.0007), shorter length of stay (P = 0.0007), and shorter overall postoperative complications (P < 0.0001) (especially cerebrospinal fluid [CSF] leak [P = 0.005], meningitis [P = 0.002], and pseudomeningocele [P = 0.002]), as compared with PFDD. CONCLUSIONS: This study confirmed that dura splitting decompression has clinical and syringomyelia improvement outcomes comparable to posterior fossa decompression with duraplasty. Compared with PFDD, DSD not only significantly shortened the operation time and length of stay, but also significantly reduced the overall complication rate, especially those related to incidence of CSF-related complications. More evidence from advanced multicenter studies are needed to require to validate the findings.


Asunto(s)
Malformación de Arnold-Chiari/cirugía , Fosa Craneal Posterior/cirugía , Descompresión Quirúrgica/métodos , Duramadre/cirugía , Procedimientos Neuroquirúrgicos/métodos , Complicaciones Posoperatorias/epidemiología , Siringomielia/cirugía , Malformación de Arnold-Chiari/diagnóstico por imagen , Malformación de Arnold-Chiari/fisiopatología , Pérdida de Líquido Cefalorraquídeo/epidemiología , Espacio Epidural , Humanos , Tiempo de Internación/estadística & datos numéricos , Meningitis/epidemiología , Tempo Operativo , Reoperación/estadística & datos numéricos , Infección de la Herida Quirúrgica/epidemiología , Siringomielia/diagnóstico por imagen , Siringomielia/fisiopatología , Resultado del Tratamiento
7.
Talanta ; 144: 1-5, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26452784

RESUMEN

In this study, we have reported the preparation of NiO/graphene (NiO/GR) nanocomposite for determination of H2O2 via a convenient solid reaction. The electrocatalytic behaviors towards H2O2 are investigated by cyclic voltammetry and chronoamperometry in alkaline aqueous solution. Electrochemical results indicate that the NiO/GR nanocomposite exhibits a high peak current towards the oxidation of H2O2. Moreover, high electrocatalytic activity toward the oxidation of H2O2 is observed with a low detection limit of 0.7664 µM, high sensitivity of 591 µA mM(-1) cm(-2), a wide linear range of 0.25-4.75 mM (R(2)=0.9971). Besides, the sensor presents many attractive features such as high stability and reproducibility.


Asunto(s)
Grafito/química , Peróxido de Hidrógeno/análisis , Límite de Detección , Nanoestructuras/química , Níquel/química , Catálisis , Electroquímica , Electrodos , Peróxido de Hidrógeno/química , Concentración de Iones de Hidrógeno , Reproducibilidad de los Resultados , Agua/química
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