Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Artículo en Chino | WPRIM | ID: wpr-955576

RESUMEN

Objective:To explore the application status and development trend of massive open online course (MOOC) in the field of higher medical education in China, so as to provide the reference for future research in this field.Methods:The related literatures collected from China National Knowledge Infrastructure (CNKI), Wanfang Data service platform, VIP database and China Biology Medicine disc were searched from their inception to March 1st, 2020, and the statistical analysis was carried out on the annual volume, journal distribution, fund support, author distribution, cited frequency, literature type and high-frequency keywords by using the bibliometrics method. The extracted data was set up in Excel 2010, and descriptive statistics was made by frequency analysis.Results:The study collected 754 articles, which were included in 262 journals, mainly medical education journals. The funding rate reached 50%. Huang Ping, Zhang Xin, Li Xinhui and seven others were core authors. Basic medical curriculum application research represented by human anatomy was the most. MOOC application research focused on theoretical curriculum. The curriculum evaluation included such five aspects as terminal evaluation, formative evaluation, platform assessment, comprehensive ability and autonomous learning ability. The research focus was the mixed teaching mode based on MOOC and its application in nursing education, traditional Chinese medicine education and continuing medical education.Conclusion:In the past five years, MOOC has developed rapidly in China's higher medical education, and the core authors have formed, but there is a lack of in-depth cooperation. In the future, we should increase the applied research of experimental (training) courses, and further improve the design of experimental research and curriculum evaluation system.

2.
Nat Commun ; 11(1): 5990, 2020 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-33239608

RESUMEN

Bioresorbable electronic stimulators are of rapidly growing interest as unusual therapeutic platforms, i.e., bioelectronic medicines, for treating disease states, accelerating wound healing processes and eliminating infections. Here, we present advanced materials that support operation in these systems over clinically relevant timeframes, ultimately bioresorbing harmlessly to benign products without residues, to eliminate the need for surgical extraction. Our findings overcome key challenges of bioresorbable electronic devices by realizing lifetimes that match clinical needs. The devices exploit a bioresorbable dynamic covalent polymer that facilitates tight bonding to itself and other surfaces, as a soft, elastic substrate and encapsulation coating for wireless electronic components. We describe the underlying features and chemical design considerations for this polymer, and the biocompatibility of its constituent materials. In devices with optimized, wireless designs, these polymers enable stable, long-lived operation as distal stimulators in a rat model of peripheral nerve injuries, thereby demonstrating the potential of programmable long-term electrical stimulation for maintaining muscle receptivity and enhancing functional recovery.


Asunto(s)
Implantes Absorbibles , Terapia por Estimulación Eléctrica/instrumentación , Traumatismos de los Nervios Periféricos/terapia , Poliuretanos/química , Tecnología Inalámbrica/instrumentación , Animales , Modelos Animales de Enfermedad , Terapia por Estimulación Eléctrica/métodos , Femenino , Humanos , Ensayo de Materiales , Músculo Esquelético/inervación , Músculo Esquelético/fisiología , Ratas , Regeneración , Nervio Ciático/lesiones , Nervio Ciático/fisiología
3.
Artículo en Chino | WPRIM | ID: wpr-828391

RESUMEN

This study is to explore the effect of Qingfei Paidu Decoction(QPD) on the host metabolism and gut microbiome of rats with metabolomics and 16 S rDNA sequencing. Based on 16 S rDNA sequencing of gut microbiome and metabolomics(GC-MS and LC-MS/MS), we systematically studied the serum metabolites profile and gut microbiota composition of rats treated with QPD for continued 5 days by oral gavage. A total of 23 and 43 differential metabolites were identified based on QPD with GC-MS and LC-MS/MS, respectively. The involved metabolic pathways of these differential metabolites included glycerophospholipid metabolism, linoleic acid metabolism, TCA cycle and pyruvate metabolism. Meanwhile, we found that QPD significantly regulated the composition of gut microbiota in rats, such as enriched Romboutsia, Turicibacter, and Clostridium_sensu_stricto_1, and decreased norank_f_Lachnospiraceae. Our current study indicated that short-term intervention of QPD could significantly regulate the host metabolism and gut microbiota composition of rats dose-dependently, suggesting that the clinical efficacy of QPD may be related with the regulation on host metabolism and gut microbiome.


Asunto(s)
Animales , Ratas , Bacterias , Clasificación , Cromatografía Liquida , Medicamentos Herbarios Chinos , Farmacología , Microbioma Gastrointestinal , Metabolómica , Espectrometría de Masas en Tándem
4.
Artículo en Chino | WPRIM | ID: wpr-828496

RESUMEN

OBJECTIVE@#To establish the optimum extraction technique and high performance liquid chromatographic (HPLC) method to simultaneously quantify nine compounds of gallic acid, hydroxy-paeoniflorin, catechin, albiflorin, paeoniflorin, pentagalloylglucose, benzoic acid, benzoylpaeoniflorin and paeonol in .@*METHODS@#Linear gradient elution was applied using water containing 0.1%phosphoric acid and acetonitrile as the mobile phase with a flow rate of 0.8 mL/min, column temperature of 30℃ and wavelength of 230 nm. The method of ultrasound extraction was used. Methanol and ethanol were used as extraction solvents, and three factors and three levels of orthogonal experiments was designed using L (3 ) table to investigate the effects of solvent concentration, ratio of liquid to material and extraction time on the total content of nine components of .@*RESULTS@#HPLC method was verified to have high specificity, sensitivity and accuracy through methodological validation, and it could be used for simultaneous quantitative analysis of nine components of . The results showed that the optimum extraction technology of nine components of was using 70%ethanol as extraction solvent, ratio of liquid to material was 200 mL/g and ultrasound extraction time was 30 min.@*CONCLUSIONS@#HPLC method for the simultaneous determination of nine components of is established, and the optimum extraction technology is confirmed.


Asunto(s)
Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos , Paeonia
5.
Food Res Int ; 126: 108604, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31732021

RESUMEN

This work aimed to develop a novel colorimetric indicator film for monitoring of food freshness based on gelatin/polyvinyl alcohol matrix incorporated with anthocyanin extracts from mulberry. The color of anthocyanin extracts solutions obviously changed from bright red to dark green in the pH range of 2.0-11.0. FTIR spectra and isothermal titration calorimetry showed that the anthocyanin extracts were successfully combined with gelatin/polyvinyl alcohol matrix by hydrogen binding and electrostatic interaction, which enhanced the stability of anthocyanin. The scanning electric microscopy showed that the compatibility between polyvinyl alcohol and gelatin were improved owing to the addition of anthocyanin extracts. With the anthocyanin extracts addition from 0 to 45 mg/100 mL mixed solution, the tensile strength decreased from 30.80 to 21.01 MPa and the elongation at break increased from 589.22% to 905.86%. The color response of film in buffer solution of different pH were in accordance with anthocyanin extracts solutions, and its color changes were clearly visible with naked eye. Finally, the film was evaluated by a test on monitoring fish spoilage, which presented visible color changes due to volatile nitrogenous compounds formed over time. These results showed that this developed film could be used as an effective method for the monitoring of food freshness.


Asunto(s)
Antocianinas/química , Embalaje de Alimentos/instrumentación , Indicadores y Reactivos/química , Morus/química , Alcohol Polivinílico/química , Alimentos Marinos , Animales , Colorimetría , Peces , Almacenamiento de Alimentos/instrumentación , Gelatina/química , Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Extractos Vegetales/química , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática
6.
Environ Sci Pollut Res Int ; 23(13): 13200-9, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27023806

RESUMEN

The occurrence and fate of four cyclic (D3 to D6) and 10 linear (L5 to L14) siloxanes were investigated in influent and effluent wastewater, sludge from a wastewater treatment plant (WWTP), and surrounding air and soil within the WWTP in Harbin, Northeast China. The mean concentrations of total siloxanes in influent and effluent were 4780 and 997 ng/L and in excess sludge and aerobic sludge were 25.1 and 32.3 µg/g dw, respectively. The concentrations in air and soil within the WWTP were 243 ng/m(3) and 4960 ng/g dw, respectively. A similar composition profile of siloxanes in influent and sludge suggests their same source. Seasonal variation with concentration was comprehensively studied. It was found that temperature and rainfall are the two important factors for the seasonal variation of siloxanes. Adsorption with sewage sludge was the major way for the removal of siloxanes during the municipal wastewater treatment process. Overall, on a daily basis, the mass loading of the Σsiloxanes into the WWTP, out of the WWTP with the effluent and sludge, were estimated to be 3.0, 0.6 and 1.3 kg, respectively. In general, 21 % of siloxanes were discharged into the receiving body (Songhua River), 43 % of siloxanes were absorbed on sludge, and 36 % of siloxanes were lost during the whole process of WWTP.


Asunto(s)
Siloxanos/análisis , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Adsorción , Contaminantes Atmosféricos/análisis , China , Ríos , Estaciones del Año , Aguas del Alcantarillado/análisis , Suelo/química
7.
Molecules ; 15(5): 3694-708, 2010 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-20657508

RESUMEN

Response surface methodology was employed to optimize the conditions for alkaline extraction of polysaccharides from Ganoderma lucidum. The results indicated that the optimum conditions were an extraction temperature of 60.1 degrees C, an extraction time of 77.3 min, a sodium hydroxide (NaOH) concentration of 5.1% and a substrate/liquid ratio of 1:21.4. Immunological assays results have shown that the alkaline soluble polysaccharides have no noticeable effects on monocyte phagocytosis and immune organ (spleen, thymus) weight of immunocompromised mice at the tested dosages. However, they could restore delayed type hypersensitivity reaction to dinitrofluorobenzene (DFNB), hemolysis antibody levels at the three doses applied, and improve the natural killer cell activity at the high-dose and medium dose.


Asunto(s)
Inmunidad/efectos de los fármacos , Extractos Vegetales/química , Polisacáridos/aislamiento & purificación , Polisacáridos/farmacología , Reishi/química , Animales , Relación Dosis-Respuesta a Droga , Métodos , Ratones , Tamaño de los Órganos , Fagocitosis/efectos de los fármacos , Bazo/inmunología , Timo/inmunología
8.
Journal of Experimental Hematology ; (6): 1275-1277, 2010.
Artículo en Inglés | WPRIM | ID: wpr-332378

RESUMEN

The aim of this study was to explore the effect of hyperbaric oxygen (HBO) preconditioning on the rejection of skin allograft in mice and its molecular mechanism. BALB/c donor mice and C57BL/6 recipients received hyperbaric oxygen preconditioning once a day for 7 days. After skin transplantation, the recipients were treated with cyclosporine A (CsA) intraperitoneally. Immunofluorescent staining technique and flow cytometry were used to observe the influence HBO on percentage of spleen lymphocytes CD3+, CD4+, CD8+ and cell adhesion molecule LFA-1 (CD11a/CD18). The results showed that as compared with control, the numbers of CD3+, CD4+, CD8+, CD4+CD11a+, CD4+ CD18+, CD8+CD11a+, CD8+CD18+ lymphocytes of spleen decreased in HBO preconditioning groups and CsA group, and decreased markedly in HBO preconditioning combined with CsA group (p<0.05); the general state of recipient mice in HBO preconditioning combined with CsA group was better than that of recipient mice received HBO preconditioning or CsA only. It is concluded that the method of HBO preconditioning combined with traditional immunosuppressive agent CsA has remarkable advantage in inhibiting the rejection of skin graft. Its molecular protective mechanism is correlated with the expression of adhesive molecules on T cell subsets.


Asunto(s)
Animales , Femenino , Masculino , Ratones , Adhesión Celular , Moléculas de Adhesión Celular , Farmacología , Ciclosporina , Farmacología , Rechazo de Injerto , Supervivencia de Injerto , Oxigenoterapia Hiperbárica , Recuento de Linfocitos , Linfocitos , Biología Celular , Metabolismo , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Trasplante de Piel , Alergia e Inmunología , Bazo , Biología Celular , Acondicionamiento Pretrasplante , Métodos
9.
Ying Yong Sheng Tai Xue Bao ; 20(7): 1551-8, 2009 Jul.
Artículo en Chino | MEDLINE | ID: mdl-19899450

RESUMEN

By the methods of phenotypic identification and SRAP makers amplification, the genetic diversity of twenty-five local tea cultivars in Guangdong Province and five contrastive cultivars from other regions was assessed and classified, and the phenotypic traits of the cultivars were clustered by Pearson correlation and Farthest neighbor methods. The coefficient of variation of the phenotypic traits was averagely 32.15%. Fine-hair had the highest coefficient of variation (42.41%), while the growth period of bud leaves had the smallest one (18.52%). Based on the cluster analysis of phenotypic traits, the test 30 tea cultivars could be clustered into 4 groups, 17 cultivars in the first group, 10 cultivars in the second group, 2 contrastive cultivars Yunnan-dayezhong and Lingyun-baimaocha in the third group, and 1 contrastive cultivar Hainan-dayezhong in the fourth group. After the amplification with 21 SRAP primers, a total of 127 fragments were detected, among which, 114 fragments were polymorphic, accounting for 88.67% of the total. The amplified fragments and polymorphic fragments per primer combination were averagely 6.05 and 5.43, respectively. At the genetic distance of 0.39 cm, the tea cultivars could be classified into three groups A, B and C, and 83.33% of the cultivars were belonged to group A. At the genetic distance of 0.31 cm, group A could be further classified into three sub-groups I , II and III, 13 cultivars in subgroup I, 2 cultivars in subgroup II, and 10 cultivars in subgroup III. It was not exactly the same between the clustering based on SRAP markers amplification and the performance of phenotypic traits.


Asunto(s)
Camellia sinensis/clasificación , Camellia sinensis/genética , Variación Genética , Técnicas de Amplificación de Ácido Nucleico/métodos , China , Marcadores Genéticos/genética , Fenotipo , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo Genético
10.
Artículo en Inglés | WPRIM | ID: wpr-267923

RESUMEN

The objective of this study was to investigate the function and mechanism of hyperbaric oxygen (HBO) in antagonizing acute graft-versus-host disease (aGVHD) and improving the rate of survival. The lethally irradiated C57BL/6 recipients were injected with bone marrow and lymphocyte of spleen from BALB/c donors and were treated with HBO, cyclosporine A (CsA) and methotrexate (MTX). T lymphocytes and subsets, adhesion molecules and cytokines were detected by flow cytometry, ELISA and RT-PCR respectively. The results showed that the survival rate in HBO group was much higher than that in allogenetic bone marrow transplantation (allo-BMT) group and CsA + MTX group; the numbers of CD3(+), CD4(+), CD8(+), CD4(+)CD11a(+), CD4(+)CD18(+), CD8(+)CD11a(+), CD8(+)CD18(+) lymphocytes in spleen were decreased markedly by HBO and CsA + MTX (p < 0.05); the levels of IL-2 and TNFalpha mRNA and their serum concentrations in HBO group were much lower than those in allo-BMT group but were higher than those in CsA + MTX group; the levels of IL-4 and IL-10 mRNA in HBO group were much higher than those in allo-BMT group and CsA + MTX group. It is concluded that HBO has more remarkable advantage in improving the rate of survival than CsA + MTX, its mechanism of anti-aGVHD is tightly correlated with the transform of T cell and its subsets and the expression of adhesion molecules and cytokines.


Asunto(s)
Animales , Femenino , Masculino , Ratones , Enfermedad Aguda , Trasplante de Médula Ósea , Citocinas , Enfermedad Injerto contra Huésped , Terapéutica , Oxigenoterapia Hiperbárica , Transfusión de Linfocitos , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Linfocitos T , Alergia e Inmunología , Irradiación Corporal Total
11.
Zhonghua Xue Ye Xue Za Zhi ; 27(4): 244-8, 2006 Apr.
Artículo en Chino | MEDLINE | ID: mdl-16875555

RESUMEN

OBJECTIVE: To explore the biological effect on NB4 cells proliferation, all-trans retinoic acid (ATRA) inducing differentiation and resistance to apoptosis by vascular endothelial growth factor (VEGF)-C cDNA transfection. METHODS: The recombinant eukaryotic expression plasmid pcDNA3.1-VEGF-C and the vacant pcDNA3.1 vector were introduced separately into NB4 cells by lipofectamine mediation. The positive clones were screened by G418 and identified by reverse transcriptase-PCR (RT-PCR) and Western blotting. The proliferation capacity of NB4/VEGF-C cells was analysed by MTT assay and colony forming assay in vitro. After NB4/VEGF-C cells were induced by ATRA, the expression level of C/EBPalpha gene, CD11b on cells surface and morphological alteration were analysed by real-time quantitative PCR (RQ-PCR), flow cytometry (FCM), and Wright-Giemsa staining, respectively. FCM Annexin V-FITC/PI dual labeling technique was performed to investigate the etoposide (Vp16) induced NB4/VEGF-C cells apoptosis and bcl-2 gene expression level in these cells was analysed by RQ-PCR. The NB4/pcDNA3.1 cells was used as control in the above experiments. RESULTS: A stable NB4 cell line that secrets VEGF-C and its control lines were established. The proliferation capacity of the former was stronger than that of the latter. The expression level of C/EBPalpha gene of NB4/VEGF-C cells on ATRA treatment was only 1/32 that of NB4/pcDNA3.1 cells. The CD11b level and the degree of differentiation of NB4/VEGF-C were weaker than that of NB4/pcDNA3.1 cells. The percentage of apoptotic NB4/VEGF-C cells induced by Vp16 [(7.20 +/- 2.52)%] was significantly lower than that of NB4/pcDNA3.1 cells [(16.07 +/- 3.58)%] (P = 0.005), but the bcl-2 gene expression level of NB4/VEGF-C cells is 2.28-fold that of NB4/pcDNA3.1 cells. CONCLUSION: The VEGF-C via VEGFR-3 signaling pathway could promote the proliferation of leukemic cells by autocrine pathway and inhibit the cell differentiation mediated by ATRA and chemotherapy-induced apoptosis. VEGF-C/VEGFR-3 signaling loops might play an important role in disease progression and be potential therapeutic target for the treatment of leukemias.


Asunto(s)
Apoptosis/fisiología , Diferenciación Celular/fisiología , Proliferación Celular , Factor C de Crecimiento Endotelial Vascular/fisiología , Apoptosis/efectos de los fármacos , Apoptosis/genética , Western Blotting , Proteína alfa Potenciadora de Unión a CCAAT/genética , Proteína alfa Potenciadora de Unión a CCAAT/metabolismo , Antígeno CD11b/genética , Antígeno CD11b/metabolismo , Diferenciación Celular/genética , Línea Celular Tumoral , ADN Complementario/genética , Resistencia a Antineoplásicos , Citometría de Flujo , Vectores Genéticos , Humanos , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección , Tretinoina/farmacología , Factor C de Crecimiento Endotelial Vascular/genética , Factor C de Crecimiento Endotelial Vascular/metabolismo
12.
Chinese Journal of Hematology ; (12): 244-248, 2006.
Artículo en Chino | WPRIM | ID: wpr-243965

RESUMEN

<p><b>OBJECTIVE</b>To explore the biological effect on NB4 cells proliferation, all-trans retinoic acid (ATRA) inducing differentiation and resistance to apoptosis by vascular endothelial growth factor (VEGF)-C cDNA transfection.</p><p><b>METHODS</b>The recombinant eukaryotic expression plasmid pcDNA3.1-VEGF-C and the vacant pcDNA3.1 vector were introduced separately into NB4 cells by lipofectamine mediation. The positive clones were screened by G418 and identified by reverse transcriptase-PCR (RT-PCR) and Western blotting. The proliferation capacity of NB4/VEGF-C cells was analysed by MTT assay and colony forming assay in vitro. After NB4/VEGF-C cells were induced by ATRA, the expression level of C/EBPalpha gene, CD11b on cells surface and morphological alteration were analysed by real-time quantitative PCR (RQ-PCR), flow cytometry (FCM), and Wright-Giemsa staining, respectively. FCM Annexin V-FITC/PI dual labeling technique was performed to investigate the etoposide (Vp16) induced NB4/VEGF-C cells apoptosis and bcl-2 gene expression level in these cells was analysed by RQ-PCR. The NB4/pcDNA3.1 cells was used as control in the above experiments.</p><p><b>RESULTS</b>A stable NB4 cell line that secrets VEGF-C and its control lines were established. The proliferation capacity of the former was stronger than that of the latter. The expression level of C/EBPalpha gene of NB4/VEGF-C cells on ATRA treatment was only 1/32 that of NB4/pcDNA3.1 cells. The CD11b level and the degree of differentiation of NB4/VEGF-C were weaker than that of NB4/pcDNA3.1 cells. The percentage of apoptotic NB4/VEGF-C cells induced by Vp16 [(7.20 +/- 2.52)%] was significantly lower than that of NB4/pcDNA3.1 cells [(16.07 +/- 3.58)%] (P = 0.005), but the bcl-2 gene expression level of NB4/VEGF-C cells is 2.28-fold that of NB4/pcDNA3.1 cells.</p><p><b>CONCLUSION</b>The VEGF-C via VEGFR-3 signaling pathway could promote the proliferation of leukemic cells by autocrine pathway and inhibit the cell differentiation mediated by ATRA and chemotherapy-induced apoptosis. VEGF-C/VEGFR-3 signaling loops might play an important role in disease progression and be potential therapeutic target for the treatment of leukemias.</p>


Asunto(s)
Humanos , Apoptosis , Genética , Fisiología , Western Blotting , Proteína alfa Potenciadora de Unión a CCAAT , Genética , Metabolismo , Antígeno CD11b , Genética , Metabolismo , Diferenciación Celular , Genética , Fisiología , Línea Celular Tumoral , Proliferación Celular , ADN Complementario , Genética , Resistencia a Antineoplásicos , Citometría de Flujo , Vectores Genéticos , Leucemia Promielocítica Aguda , Genética , Metabolismo , Patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección , Tretinoina , Farmacología , Factor C de Crecimiento Endotelial Vascular , Genética , Metabolismo , Fisiología
13.
Artículo en Chino | WPRIM | ID: wpr-272795

RESUMEN

<p><b>OBJECTIVE</b>To observe the change of auditory event-related potentials (P300) and sympathetic skin response (SSR) in people with insomia of Sweet Dream Capsule therapy.</p><p><b>METHODS</b>30 patients meeting criteria for primary insomnia and 30 healthy volunteers with age matching controls were selected for the study. P300 and SSR were measured before treatment of Sweet Dream Capsule and at week 4 , 8 of the therapeutic course. That the change of P300 and SSR before and after treatment and their relations with PSQI were studied.</p><p><b>RESULT</b>Compared with those of normal controls, both P300 latency and SSR latency were prolonged while amplitude was decreased in patients with insomnia (P < 0.01). P300 amplitude was increased significantly at central (Cz) electrode sites only at week 8 when compared with amplitude before treatment (P < 0.05). With improvement of symptom and PSQI scores, latency and amplitude of SSR were improved at week 4 and week 8 (P < 0.05 and P < 0.01) .</p><p><b>CONCLUSION</b>P300 has a some improvement in people with insomia of Sweet Dream Capsule therapy while SSR im proves significantly, and PSQI scores are ameliorated too.</p>


Asunto(s)
Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cápsulas , Combinación de Medicamentos , Medicamentos Herbarios Chinos , Farmacología , Estimulación Eléctrica , Potenciales Relacionados con Evento P300 , Potenciales Evocados Somatosensoriales , Fitoterapia , Plantas Medicinales , Química , Piel , Trastornos del Inicio y del Mantenimiento del Sueño , Quimioterapia , Sistema Nervioso Simpático
14.
Yao Xue Xue Bao ; 38(4): 241-4, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12889119

RESUMEN

AIM: To assess the antioxidative properties and the mechanism of action of dihydromyricetin (DMY) from Ampelopsis grossedentata. METHODS: The antioxidative properties of DMY were measured by scavenging 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and inhibiting lipid peroxidation induced by FeSO4-edetic acid in linoleic acid. The mechanism of antioxidative properties of DMY was tested by measuring the chelating activities of DMY for Fe2+ with ultraviolet spectrum (UV) method. RESULTS: The specific absorption of DPPH radical solution at 517 nm was reduced 73.3%-91.5% when DMY was added into the reaction solution in the concentration range from 0.01% to 0.04%. DMY was shown to greatly inhibit the increase of lipid peroxidation (LPO) values in linolei acid system catalyzed by FeSO4-edetic acid. The reaction rates (A532.min-1) of lipid peroxidation were 0.0021-0.0004 in the concentration range from 0.01% to 0.04% and the inhibition activities of DMY was found to be in a concentration-dependent manner. The mechanism of antioxidative properties of DMY was chelating Fe2+ in the Fe(2+)-dependent lipid peroxidation system. CONCLUSION: DMY showed great antioxidative effect and would be a good natural antioxidant.


Asunto(s)
Ampelopsis/química , Antioxidantes/farmacología , Flavonoles/farmacología , Peroxidación de Lípido/efectos de los fármacos , Antioxidantes/aislamiento & purificación , Quelantes/farmacología , Flavonoles/química , Flavonoles/aislamiento & purificación , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Estructura Molecular , Plantas Medicinales/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA