Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Food Sci Nutr ; 12(2): 1035-1045, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38370061

RESUMEN

Resveratrol (RSV) is a natural polyphenol compound found in various plants that has been shown to have potential benefits for preventing aging and supporting cardiovascular health. However, the specific signal pathway by which RSV protects the aging heart is not yet well understood. This study aimed to explore the protective effects of RSV against age-related heart injury and investigate the underlying mechanisms using a D-galactose-induced aging model. The results of the study indicated that RSV provided protection against age-related heart impairment in mice. This was evidenced by the reduction of cardiac histopathological changes as well as the attenuation of apoptosis. RSV-induced cardioprotection was linked to a significant increase in antioxidant activity and mitochondrial transmembrane potential, as well as a reduction in oxidative damage. Additionally, RSV inhibited the production of pro-inflammatory cytokines such as interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α). Furthermore, the expression of toll-like receptor 4 (TLR4), nuclear factor kappa-B p65 (NF-κB p65), and notch 1 protein were inhibited by RSV, indicating that inhibiting the Notch/NF-κB pathway played a critical role in RSV-triggered heart protection in aging mice. Moreover, further data on intestinal function demonstrated that RSV significantly increased short-chain fatty acids (SCFAs) in intestinal contents and reduced the pH value in the feces of aging mice. RSV alleviated aging-induced cardiac dysfunction through the suppression of oxidative stress and inflammation via the Notch/NF-κB pathway in heart tissue. Furthermore, this therapeutic effect was found to be associated with its protective roles in the intestine.

2.
Radiology ; 301(1): 154-162, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34374594

RESUMEN

Background The value of measuring mechanical properties to categorize various pathophysiologic states of the liver is as yet undetermined in chronic hepatitis B (CHB) or C (CHC). Purpose To evaluate multiparametric three-dimensional (3D) MR elastography as a means of detecting early necroinflammation, distinguishing necroinflammation from fibrosis, and gauging the severity of portal hypertension (PH) in CHB or CHC. Materials and Methods From January 2015 to September 2019, participants with CHB or CHC were prospectively enrolled from a single institution and were divided into two groups: those with liver biopsy and no evidence of PH (group 1) and those with PH and a hepatic venous pressure gradient (HVPG) measurement (group 2). For group 3, healthy volunteers were separately recruited from a nearby community. Multiple viscoelastic parameters (shear stiffness [SS], storage modulus, loss modulus, and damping ratio [DR]) were determined at 3D MR elastography at 60 Hz, and multivariable logistic or linear regression analysis was used to assess associations of mechanical parameters with histologic scores and HVPG. Results A total of 155 participants (median age, 41 years [interquartile range, 32-48 years]; 85 women) were in group 1 (training set: n = 78, validation set: n = 77), 85 participants (median age, 57 years [interquartile range, 43-61 years]; 51 women) in group 2, and 60 healthy volunteers (median age, 49 years [interquartile range, 27-64 years]; 38 men) in group 3. The liver DR was higher in participants with necroinflammation (DR, 0.13 ± 0.03) versus those without (at liver fibrosis stage F0) (DR, 0.10 ± 0.02; P < .001). Liver DR and SS together performed well in the diagnosis of necroinflammation (area under the receiver operating characteristic curve [AUC], 0.88 [95% CI: 0.79, 0.96]) and the scoring of moderate to severe activity (AUC, 0.88 [95% CI: 0.81, 0.95]) in the validation data set. Liver DR (regression coefficient [ß] = -30.3 [95% CI: -58.0, -2.5]; P = .03) and splenic SS (ß = 2.3 [95% CI: 1.7, 2.9]; P < .001) were independently associated with HVPG. Conclusion Three-dimensional MR elastography may detect early necroinflammation, distinguish necroinflammation from liver fibrosis, and correlate with hepatic venous pressure gradient in chronic hepatitis B and C. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Reeder in this issue.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Hepatitis B Crónica/complicaciones , Hepatitis C Crónica/complicaciones , Hipertensión Portal/complicaciones , Imagenología Tridimensional/métodos , Inflamación/diagnóstico por imagen , Cirrosis Hepática/complicaciones , Adulto , Estudios Transversales , Femenino , Humanos , Hipertensión Portal/diagnóstico por imagen , Hipertensión Portal/patología , Inflamación/complicaciones , Inflamación/patología , Hígado/diagnóstico por imagen , Hígado/patología , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/patología , Masculino , Persona de Mediana Edad , Estudios Prospectivos
3.
Carbohydr Polym ; 202: 581-590, 2018 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-30287039

RESUMEN

The present study aimed to determine the cardioprotective effect of Ganoderma atrum polysaccharide (PSG-1) in doxorubicin (DOX)-treated mice and its underlying mechanism. Results indicated that PSG-1 treatment significantly alleviated DOX-induced myocardial damage via attenuating apoptosis and maintaining the structure of myocardial mitochondria. Meanwhile, PSG-1-evoked cardioprotection was associated with an increase of manganese superoxide dismutase activity and decrease of caspases activities. Moreover, administration of PSG-1 suppressed DOX-induced mitochondrial disorders, which was evidenced by reducing reactive oxygen species, elevating mitochondrial membrane potential and inhibiting the opening of mitochondrial permeability transition pore. PSG-1 was also found to reduce the release of cytochrome c from mitochondria to cytoplasm in mice subjected to DOX. Finally, our findings have provided comprehensive evidence for the cardioprotective effects of PSG-1 via reduction of apoptosis mediated by modification of the mitochondrial intrinsic apoptotic pathway, indicating that PSG-1 could be developed as an effective therapeutic strategy to prevent DOX-induced cardiotoxicity in clinical settings.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Doxorrubicina/farmacología , Ganoderma/química , Mitocondrias/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Polisacáridos/farmacología , Animales , Antibióticos Antineoplásicos/química , Doxorrubicina/química , Ratones , Mitocondrias/metabolismo , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Polisacáridos/química , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismo
4.
Sci Rep ; 8(1): 5566, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29615642

RESUMEN

A developed Fourier transform infrared spectroscopy (FT-IR) was employed to investigate changes of protein conformation, which played significant roles in maintaining stable protein networks of white croaker surimi gel, exploring the relationship between protein conformation and surimi gel networks. Spectra of surimi and gels with different grades (A, AA, FA and SA) were analyzed by tri-step FT-IR method and peak-fitting of deconvolved and baseline corrected amide I bands (1600~1700 cm-1). The result showed that α-helix was the main conformation of surimi proteins. During surimi gelation, α-helix of myosin partially transformed into ß-sheet, ß-turn and random coil structures. ß-sheet and random coil structures were the main protein conformations maintaining the structure of surimi gel, of which ß-sheet made the main contribution to gel strength. Scanning electron microscopy (SEM) result revealed that surimi gels had a fibrous and homogeneous network structure. Moreover, ordered interconnections between three-dimensional proteins networks of gels were inclined to emerge in higher grade surimi, in agreement with the gel strength results. It was demonstrated that the tri-step FT-IR spectroscopy combined with peak-fitting could be applicable for exploration of surimi protein conformation changes during gelation to deepen understanding of its effect on gel quality.


Asunto(s)
Proteínas de Peces/química , Microscopía , Espectroscopía Infrarroja por Transformada de Fourier , Amidas/química , Geles , Conformación Proteica en Hélice alfa , Estabilidad Proteica
5.
Int J Biol Macromol ; 98: 398-406, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28108410

RESUMEN

Ganoderma atrum polysaccharide (PSG-1), a main polysaccharide from Ganoderma atrum, possesses potent antioxidant capacity and cardiovascular benefits. The aim of this study was to investigate the role of PSG-1 in oxidative stress and apoptosis in human umbilical vein endothelial cells (HUVECs) under anoxia/reoxygenation (A/R) injury conditions. The results showed that exposure of HUVECs to A/R triggered cell death and apoptosis. Administration of PSG-1 significantly inhibited A/R-induced cell death and apoptosis in HUVECs. PSG-1-reduced A/R injury was mediated via mitochondrial apoptotic pathway, as evidenced by elevation of mitochondrial Bcl-2 protein and mitochondrial membrane potential, and attenuation of Bax translocation, cytochrome c release and caspases activation. Furthermore, PSG-1 enhanced the activities of superoxide dismutase, catalase and glutathione peroxidase and glutathione content, and concomitantly attenuated reactive oxygen species generation, lipid peroxidation and glutathione disulfide content. The antioxidant, N-acetyl-l-cysteine, significantly ameliorated all of these endothelial injuries caused by A/R, suggesting that antioxidant activities might play a key role in PSG-1-induced endothelial protection. Taken together, these findings suggested that PSG-1 could be as a promising adjuvant against endothelial dysfunction through ameliorating oxidative stress and apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Polisacáridos Fúngicos/farmacología , Ganoderma/química , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Estrés Oxidativo/efectos de los fármacos , Oxígeno/metabolismo , Antioxidantes/metabolismo , Caspasas/metabolismo , Supervivencia Celular/efectos de los fármacos , Citocromos c/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Peroxidación de Lípido/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteína X Asociada a bcl-2/metabolismo
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(2): 390-3, 2015 Feb.
Artículo en Chino | MEDLINE | ID: mdl-25970898

RESUMEN

Three feature extraction algorithms, such as the principal component analysis (PCA), the discrete cosine transform (DCT) and the non-negative factorization (NMF), were used to extract the main information of the spectral data in order to weaken the influence of the spectral fluctuation on the subsequent quantitative analysis results based on the SERS spectra of the pesticide thiram. Then the extracted components were respectively combined with the linear regression algorithm--the partial least square regression (PLSR) and the non-linear regression algorithm--the support vector machine regression (SVR) to develop the quantitative analysis models. Finally, the effect of the different feature extraction algorithms on the different kinds of the regression algorithms was evaluated by using 5-fold cross-validation method. The experiments demonstrate that the analysis results of SVR are better than PLSR for the non-linear relationship between the intensity of the SERS spectrum and the concentration of the analyte. Further, the feature extraction algorithms can significantly improve the analysis results regardless of the regression algorithms which mainly due to extracting the main information of the source spectral data and eliminating the fluctuation. Additionally, PCA performs best on the linear regression model and NMF is best on the non-linear model, and the predictive error can be reduced nearly three times in the best case. The root mean square error of cross-validation of the best regression model (NMF+SVR) is 0.0455 micormol x L(-1) (10(-6) mol x L(-1)), and it attains the national detection limit of thiram, so the method in this study provides a novel method for the fast detection of thiram. In conclusion, the study provides the experimental references the selecting the feature extraction algorithms on the analysis of the SERS spectrum, and some common findings of feature extraction can also help processing of other kinds of spectroscopy.

7.
J Chem Phys ; 135(24): 241102, 2011 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-22225136

RESUMEN

The ability to achieve sub-wavenumber resolution (0.6 cm(-1)) and a large signal-to-noise ratio in high-resolution broadband sum-frequency generation vibrational spectroscopy (HR-BB-SFG-VS) allows for the detailed SFG spectral lineshapes to be used in the unambiguous determination of fine spectral features. Changes in the structural spectroscopic phase in SFG-VS as a function of beam polarization and experimental geometry proved to be instrumental in the identification of an unexpected 2.78 ± 0.07 cm(-1) spectral splitting for the two methyl groups at the vapor/dimethyl sulfoxide (DMSO, (CH(3))(2)SO) liquid interface as well as in the determination of their orientational angles.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(7): 1021-5, 2005 Jul.
Artículo en Chino | MEDLINE | ID: mdl-16241045

RESUMEN

A new equipment of pulsed DC discharge supersonic molecular beam was set up for producing transient species. Thepulsed DC discharge can be used stably under 10 kV. In data collection using software, it can be utilized as gated integrators and averagers. Using this equipment, the processes of N2O discharge were studied. The emission spectra of N2O+ (A2sigma+ - X2IIi) were obtained. From the intensity of vibrational spectra, the vibrational populations of the N2O+ (A2sigma+ ) states were calculated. Compared with other results, A states of N2O+ depart even more from a Boltzmann distribution.


Asunto(s)
Técnicas Electroquímicas/métodos , Óxido Nitroso/química , Espectrometría de Fluorescencia/métodos , Algoritmos , Técnicas Electroquímicas/instrumentación , Programas Informáticos , Espectrometría de Fluorescencia/instrumentación
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(12): 1502-5, 2004 Dec.
Artículo en Chino | MEDLINE | ID: mdl-15828311

RESUMEN

Using crossed molecular beam-chemiluminescence apparatus, visible chemiluminescence in the region of 300-900 nm was measured from the gas-phase reaction of microwave discharge of CF4 diluted in Ar with carbon disulfide at various pressures. The geometries and frequencies of possible reaction products were respectively investigated at the B3LYP/6-311 + + G (3df, 2pd) and MP2/6-311 + G(d, p) levels. Chemiluminescence spectrum was assigned to emission spectrum of the electronically excited states of F2S2. From the analysis of spectrum and reaction mechanism, it is proposed that carbon disulfur was dissociated by metastable Ar generated from microwave discharge. The electronically excited state of F2S2 was obtained from multistage reactions of the dissociative products with atoms F generated from microwave discharge.


Asunto(s)
Luminiscencia , Microondas , Disulfuro de Carbono , Mediciones Luminiscentes , Modelos Químicos , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...