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1.
Quant Imaging Med Surg ; 14(5): 3581-3592, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38720848

RESUMO

Background: One in four individuals with Parkinson's disease (PD) experience cognitive impairment (CI). However, few practical models integrating clinical and neuroimaging biomarkers have been developed to address CI in PD. This study aimed to evaluate the correlation between circulating neuron-specific enolase (NSE) levels, substantia nigra hyperechogenicity (SNH), and cognitive function in PD and to develop a nomogram based on clinical and neuroimaging biomarkers for predicting CI in patients with PD. Methods: A total of 385 patients with PD who underwent transcranial sonography (TCS) from January 2021 to December 2022 at Beijing Tiantan Hospital, Capital Medical University, were recruited as the training cohort. For validation, 165 patients with PD treated from January 2023 to December 2023 were enrolled. Data for SNH, plasma NSE, and other clinical measures were collected, and cognitive function was assessed using the Montreal Cognitive Assessment (MoCA). Logistic regression analysis was employed to select potential risk factors and establish a nomogram. The receiver operating characteristic curve and calibration curve were generated to evaluate the performance of the nomogram. Results: Patients with PD exhibiting CI displayed advanced age, elevated Unified PD Rating Scale-III (UPDRS-III) score, an increased percentage of SNH, higher levels of plasma NSE and homocysteine (Hcy), a larger SNH area, and lower education levels compared to PD patients without CI. Gender [odds ratio (OR) =0.561, 95% confidence interval (CI): 0.330-0.954, P=0.03], age (OR =1.039; 95% CI: 1.011-1.066; P=0.005), education level (OR =0.892; 95% CI: 0.842-0.954; P<0.001), UPDRS-III scores (OR =1.026; 95% CI: 1.009-1.043; P=0.003), plasma NSE concentration (OR =1.562; 95% CI: 1.374-1.776; P<0.001), and SNH (OR =0.545; 95% CI: 0.330-0.902; P=0.02) were independent predictors of CI in patients with PD. A nomogram developed using these six factors yielded a moderate discrimination performance with an area under the curve (AUC) of 0.823 (95% CI 0.781-0.864; P<0.001). The calibration curve demonstrated acceptable agreement between predicted outcomes and actual values. Validation further confirmed the reliability of the nomogram, with an AUC of 0.864 (95% CI: 0.805-0.922; P<0.001). Conclusions: The level of NSE in plasma and the SNH assessed by TCS are associated with CI in patients with PD. The proposed nomogram has the potential to facilitate the detection of cognitive decline in individuals with PD.

2.
Int J Biol Macromol ; 208: 1063-1071, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35378154

RESUMO

This study investigated the adsorption behavior of Pb2+ by three different oxidized yeast ß-glucans (OYG) and their effect on lead-induced PC12 cytotoxicity. The analysis revealed that the adsorption kinetics conformed to pseudo-first-order model and the adsorption capacities for Pb2+ (36.50, 41.61 and 50.31 µg/mg for OYG1-3) showed a positive correlation with oxidation degree (15.2%, 47.3% and 71.2% for OYG1-3). Additionally, the lead adsorption by OYGs showed an endothermic process and the adsorption capacity increased with the increasing Pb2+ concentration in the aqueous phase. Then, it was found that OYGs were biocompatible and could increase cell viability from 60% to 80% during lead stress. Nuclear staining revealed an inhibitory effect of OYGs on cell apoptosis, with the best performance for OYG3. Furthermore, OYGs could significantly suppress lead-induced production of reactive oxygen species (ROS) and nitric oxide (NO) in PC12 cells. Specifically, when being supplemented with 20 µg/mL OYG3, the increase of fluorescence intensity caused by the production of ROS and NO in PC12 cells were significantly alleviated from 2.65 and 2.6 to 1.23 and 1.35-fold, respectively. Our findings indicate that OYGs could adsorb lead effectively and protect PC12 cells from lead-induced cytotoxicity.


Assuntos
Saccharomyces cerevisiae , beta-Glucanas , Adsorção , Animais , Íons , Cinética , Chumbo/toxicidade , Células PC12 , Ratos , Espécies Reativas de Oxigênio , beta-Glucanas/farmacologia
3.
Opt Express ; 29(6): 8967-8984, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33820336

RESUMO

Directed at the strong correlation among the input parameters and long measurement chain, which are difficult for uncertainty analysis with the guide of the expression of uncertainty in the measurement (GUM) method, a novel dynamic stereo vision measurement system based on the quaternion theory is presented to reduce the orthogonality restrictions of shafting manufacturing and application. According to the quaternion theory in the kinematic model of the cameras and the analytical solution of uncertainty with the GUM method, the complete, detailed, and continuous uncertainty results of the full-scale measurement space can be obtained. Firstly, one-dimensional turntables and rigid connections are utilized to form the motion cores and the automatic control carriers in the system. Secondly, the novel measurement model is used in the measurement process to shorten the calibration and measurement chains. Once the system based on the novel measurement model is set up, the analytical solution of uncertainty is utilized in the accuracy process. During the analysis process, the strong correlation among the extrinsic parameters is decoupled by introducing virtual circles and the measurement strategy with the GUM method. Through analyzing the relationship among the attitude angles, the major factors which influence the uncertainties in each axis and the final uncertainty are clarified. Moreover, the analytical continuous uncertainty maps for the uncertainties along each axis, combined standard uncertainty, and the expanded uncertainty are illustrated and the uncertainty variation tendency is declared. Finally, the analytical solution of uncertainty with the GUM method proposed in this paper predicts the uncertainty in the full-scale space and provides a new idea of the uncertainty analysis for the complicated combined measurement system.

4.
Food Chem ; 350: 129223, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33607408

RESUMO

This work investigated selenium (Se) release kinetics and mechanism from exopolysaccharide-selenium nanoparticles (EPS-SeNPs, Se/EPS = 1/20, 1/1 and 4/3) in simulated gastric (SGF) and intestinal fluids (SIF) using kinetics models of Zero order, First order, Higuchi, Hixson-Crowell and Korsmeyer-Peppas. EPS-SeNPs showed an increase in size from 80-125 nm to 250-320 nm and more ambiguous boundary after gastrointestinal digestion. Se/EPS ratio and pH had significant influence on Se release. Se release kinetics from EPS-SeNPs (Se/EPS = 1/1 and 4/3 in SGF) followed a classical Fickian diffusion, in contrast to an erosion governed by macromolecular chains relaxation for Se/EPS = 1/20 in SIF. Se release from EPS-SeNPs (Se/EPS = 1/1 and 4/3 in SIF) was well-fitted to Korsmeyer-Peppas model and followed a non-Fickian mechanism controlled by both diffusion and erosion. Additionally, EPS-SeNPs (Se/EPS = 1/20) showed a low Se release after SGF digestion, but a high release after SIF digestion, suggesting its application in controlled release of Se-enriched supplements for Se-deficiency treatment.


Assuntos
Biomimética , Cordyceps/química , Polissacarídeos Fúngicos/química , Trato Gastrointestinal/metabolismo , Selênio/química , Cinética , Nanopartículas/química
5.
Carbohydr Polym ; 250: 116924, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33049838

RESUMO

This work was to investigate the effect of the degree of oxidation (DO) on the structure, solution properties and morphology of yeast ß-glucan. Five different degrees of oxidized yeast ß-glucan (OYG1-5) samples were controllably prepared by TEMPO-mediated oxidation on C-6 position. Namely, the -CH2OH units were oxidized into -COO-/-COOH, and the DO was quantified to be 10.0∼71.2% by potentiometric titration. With an increase of the DO, the OYG samples had a remarkable increase in solubility as indicated by the decreasing turbidity, particle size and zeta-potential, and showed an overall decrease from 2.63 × 106 to 1.43 × 105 g/mol in molecular weight and from 3.95 to 1.66 in polydispersity. OYG1-4 with DO from 10.0% to 47.3% had aggregate morphology with different sizes, while OYG5 with DO of 71.2% showed uniformly dispersed chains and a loose network formed by chain entanglement. These findings demonstrated that the solution properties and morphology of yeast ß-glucan can be altered by adjusting the DO.

6.
Bioresour Technol ; 273: 394-403, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30458409

RESUMO

This study investigated the effects and related mechanisms of ultrasound- and alkali-assisted enzymolysis on production of water-soluble yeast ß-glucan (WSYG). Results indicated that ultrasound and alkali pretreatments reduced the particle size of yeast ß-glucan (YG) from 8.80 µm to 1.77 and 7.19 µm, respectively. Ultrasound-induced cavitation disrupted YG aggregates to a coarse appearance and exposed internal structure. Alkali penetrated into YG particles and broke the YG aggregates into a flake-like morphology by cleaving the linkages within YG chains. Both pretreatments facilitated enzymolysis by enlarging the YG surface area and increased the WSYG yield to 32.3% and 36.2%, respectively. Meanwhile, the purity of WSYG reached 98.8% after zymoprotein removal by DEAE-Sepharose fast flow column. This work not only provides a green method for producing high-purity and high-yield WSYG, but also reveals the mechanisms of ultrasound and alkali pretreatments for improving enzymolysis efficiency by loosening the YG structure and increasing the surface area.


Assuntos
beta-Glucanas/química , Álcalis/química , Saccharomyces cerevisiae , Solubilidade , Ondas Ultrassônicas , Água/química
7.
Zhongguo Zhong Yao Za Zhi ; 32(15): 1508-10, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17972574

RESUMO

OBJECTIVE: To study the effects of high temperature stress on the root vitality and leaf biochemical indexes in populations of Pinellia ternate. METHOD: The leaf activity of SOD, contents of MDA and free praline and root vitality were determined after a treatment of high temperature stress (35 degrees C/25 degrees C) was given to different populations of P. ternate. RESULT AND CONCLUSION: By stress time increasing, the leaf SOD and free praline rose firstly and then dropped, the content of MDA increased while the root ability decreased in all populations. And the response of populations of P. ternate to high temperature was significantly different.


Assuntos
Resposta ao Choque Térmico/fisiologia , Pinellia/metabolismo , Raízes de Plantas/fisiologia , Plantas Medicinais/metabolismo , China , Ecossistema , Temperatura Alta , Malondialdeído/metabolismo , Pinellia/fisiologia , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Plantas Medicinais/fisiologia , Prolina/metabolismo , Superóxido Dismutase/metabolismo
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