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2.
Molecules ; 26(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34361712

RESUMO

The genus Maytenus is a member of the Celastraceae family, of which several species have long been used in traditional medicine. Between 1976 and 2021, nearly 270 new compounds have been isolated and elucidated from the genus Maytenus. Among these, maytansine and its homologues are extremely rare in nature. Owing to its unique skeleton and remarkable bioactivities, maytansine has attracted many synthetic endeavors in order to construct its core structure. In this paper, the current status of the past 45 years of research on Maytenus, with respect to its chemical and biological activities are discussed. The chemical research includes its structural classification into triterpenoids, sesquiterpenes and alkaloids, along with several chemical synthesis methods of maytansine or maytansine fragments. The biological activity research includes activities, such as anti-tumor, anti-bacterial and anti-inflammatory activities, as well as HIV inhibition, which can provide a theoretical basis for the better development and utilization of the Maytenus.


Assuntos
Alcaloides/química , Maitansina/análogos & derivados , Maytenus/química , Compostos Fitoquímicos/química , Sesquiterpenos/química , Triterpenos/química , Alcaloides/classificação , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Fármacos Anti-HIV/química , Fármacos Anti-HIV/isolamento & purificação , Fármacos Anti-HIV/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Humanos , Maitansina/isolamento & purificação , Maitansina/farmacologia , Maytenus/metabolismo , Estrutura Molecular , Compostos Fitoquímicos/classificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Plantas Medicinais , Sesquiterpenos/classificação , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Relação Estrutura-Atividade , Triterpenos/classificação , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
3.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(2): 122-127, 2020 Apr 01.
Artigo em Chinês | MEDLINE | ID: mdl-32314882

RESUMO

OBJECTIVE: This study aimed to evaluate the effects of porcine acellular cartilaginous matrix (pACM) on the proliferation and differentiation of human adipose-derived stromal cells (hADSCs). METHODS: pACM was prepared from porcine articular cartilage through decellularization treatment. hADSCs were isolated from human adipose tissues and cultured with different pACM concentrations. No pACM was used as the control group. The effect of pACM on hADSCs proliferation was detected by CCK-8 method. Moreover, the effect of pACM on hADSCs chondrogenic differentiation was analyzed through fluorescence quantitative polymerase chain reaction and Western blot. RESULTS: hADSCs proliferation rate in 0.5, 1.0, and 2.0 mg·mL⁻¹ pACM groups was not significantly different from that in the control group, whereas that in 4.0 and 8.0 mg·mL⁻¹ pACM group was lower than that in the control group (P<0.05). The expression levels of pACM chondrogenic genes, including SOX-9, collagen type Ⅱ alpha 1 chain (COL2A1), and aggrecan (ACAN) and cell adhesion-related gene LAMININ in 0.5, 1.0, and 2.0 mg·mL⁻¹ pACM group were higher than those of the control group (P<0.05), but that of a stemness-related gene Notch-1 was lower than that of the control group (P<0.05). No statistical difference was found in the expression of a lipogenesis-related gene peroxisome proliferator-activated receptor-γ (PPAr-γ) (P>0.05). The expression levels of chondrogenic proteins (SOX-9, COL2A1, and ACAN) were higher than those of the control group (P<0.05). CONCLUSIONS: Appropriate pACM con-centrations do not affect hADSCs proliferation but can induce hADSCs chondrogenic differentiation.


Assuntos
Adipócitos , Células-Tronco , Tecido Adiposo , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Condrogênese , Humanos , Células Estromais , Suínos
4.
Ying Yong Sheng Tai Xue Bao ; 30(5): 1743-1753, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31107031

RESUMO

Bamboo forests have an efficient carbon sequestration capacity and play an important role in responding to global climate change. However, the current estimation of bamboo carbon storage has some errors, leading to uncertainty in the spatiotemporal pattern of bamboo forest carbon storage. This study simulated aboveground carbon storage of Zhejiang Province, China, during 1984-2014 based on the combination of an improved BIOME-BGC (biogeochemical cycles) model and remote sensing data, with the accuracy being verified with forest resource inventory data. The spatio-temporal distribution and environmental factors of aboveground carbon storage were analyzed. The results showed that the simulated carbon storage was accurate, with average correlation coefficient (r), root mean square error (RMSE) and relative bias (rBIAS) being 0.75, 7.24 Mg C·hm-2 and -2.57 Mg C·hm-2, respectively. Generally, the aboveground carbon storage of bamboo forests in the whole province tended to increase from 1984 to 2014, the range of aboveground carbon density was 13.10-17.14 Mg C·hm-2, and that of the total aboveground carbon storage was between 9.94-17.19 Tg C. The high aboveground carbon storage of bamboo was mainly distributed in developed bamboo industry areas, such as Anji, Lin'an, and Longyou. The change of aboveground carbon storage in bamboo forest was significantly correlated with temperature, precipitation, radiation, CO2 concentration and nitrogen deposition, with higher partial correlation coefficients between precipitation and temperature and carbon storage.


Assuntos
Sequestro de Carbono , Florestas , Biomassa , Carbono , China , Ecossistema , Monitoramento Ambiental , Sasa , Análise Espaço-Temporal , Árvores
5.
Ying Yong Sheng Tai Xue Bao ; 29(7): 2391-2400, 2018 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-30039679

RESUMO

Based on the MODIS surface reflectance data, five vegetation indices, including norma-lized difference vegetation index (NDVI), simple ratio index (SR), Gitelson green index (GI), enhanced vegetation index (EVI) and soil adjusted vegetation index (SAVI) were constructed as remote sensing variables, coupled with the seven original spectral reflectance bands of MODIS. Stepwise regression and correlation analysis were used to select the variables, and the stepwise regression and Back Propagation (BP) neural network models were constructed based on the measured LAI to retrieve the LAI time series data of Phyllostachys praecox (Lei bamboo) forest during the period from January 2014 to March 2017. The retrieval results were compared with MOD15A2 LAI products during the same period. The results showed that SR was the single variable selected for the stepwise regression model. The correlations of LAI with bands b1, b2, b3, b7 and five vegetation indices were significant, which could be used as input variables of BP neural network model. There was a significant correlation between the LAI estimated from BP neural network and measured LAI, with the R2 of 0.71, RMSE of 0.34, and RMSEr of 13.6%. R2 was increased by 10.9%, RMSE decreased by 5.6%, and RMSEr decreased by 12.3% compared with LAI estimated from stepwise regression method. R2 was increased by 54.5%, RMSE decreased by 79.3%, and RMSEr decreased by 79.1% compared with MODIS LAI. The LAI of Lei bamboo forest could be accurately retrieved using BP neural network method based on MODIS reflectance time series data, which would be a feasible method for rapid monitoring of LAI in Lei bamboo forest.


Assuntos
Folhas de Planta , Poaceae/fisiologia , Florestas , Redes Neurais de Computação , Tecnologia de Sensoriamento Remoto
6.
Anim Sci J ; 89(2): 505-509, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28967208

RESUMO

The aim of this study was to investigate the effects of cyclophosphamide (CPA) on cashmere shedding in cashmere goats. Thirty-two castrated Liaoning cashmere goats were randomly allotted to four groups, with eight replicates in each group. The four groups were injected intravenously with CPA doses of 0, 15, 20 and 25 mg/kg body weight, respectively. Feed intake, body weight, body temperature, and sphygmus were recorded and the erythrocyte count, leukocyte count, hemoglobin content, and cashmere yield and length were determined. CPA has no significant effect on feed intake, body weight, body temperature, or sphygmus of cashmere goats. It was found that CPA significantly decreased the erythrocyte count and hemoglobin content in cashmere goats on the days immediately following injection, but the effects on erythrocytes diminished within 6 days, with hemoglobin content returning to normal within 10 days. Cashmere fiber began to shed on about day 10 after injection with CPA. CPA had no significant effect on cashmere length but significantly increased cashmere yield. The results indicate that CPA can induce cashmere shedding and achieve the purpose of concentrated defleecing. A dose of 20 mg/kg body weight is preferable for hair removal and regrowth in cashmere goats.


Assuntos
Ciclofosfamida/administração & dosagem , Ciclofosfamida/farmacologia , Cabras/fisiologia , Remoção de Cabelo/métodos , Cabelo/efeitos dos fármacos , Cabelo/crescimento & desenvolvimento , Muda/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Contagem de Eritrócitos , Cabras/sangue , Hemoglobinas/metabolismo , Injeções Intravenosas , Masculino , Fatores de Tempo
7.
Talanta ; 170: 350-357, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28501180

RESUMO

A sensitive and stable bioassay for the detection of Aß oligomer (Aßo), a potentially promising candidate biomarker for Alzheimer's disease (AD) diagnosis, was developed using Fe3O4 magnetic nanoparticles (MNPs) as the recognition and concentration elements and BaYF5:Yb,Er upconversion nanoparticles (UCNPs) as highly sensitive labels, conjugated with the Aßo aptamer (DNA1) and the complementary oligonucleotide of the Aßo aptamer (DNA2), respectively. The DNA1 hybridized with DNA2 to form the duplex structure on the surface of the MNPs/UCNPs nanocomposites probe. When the target Aßo was introduced, the aptamer DNA1 preferentially bound with Aßo and caused the dissociation of some complementary DNA2, liberating some UCNP-labeled complementary DNA2 and leading to a decreased upconversion fluorescent intensity on the surface of MNPs. The decreased fluorescence intensity of UCNPs was related to the concentration of Aßo in the range of 0.2-15nM with a detection limit of 36 pM. The developed method then was successfully applied to measure Aßo in artificial cerebrospinal fluid. Benefiting from the magnetic separation and concentration effect of MNPs, the high sensitivity of UCNPs, as well as the selectivity and stability of the aptamer, the present strategy offered valuable information related to early diagnosis of AD process.


Assuntos
Peptídeos beta-Amiloides/líquido cefalorraquidiano , Aptâmeros de Nucleotídeos/química , Bário/química , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Elementos da Série dos Lantanídeos/química , Nanopartículas de Magnetita/química , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/análise , Érbio/química , Humanos , Nanopartículas de Magnetita/ultraestrutura , Nanopartículas/química , Nanopartículas/ultraestrutura , Itérbio/química , Ítrio/química
8.
J Sep Sci ; 40(14): 2933-2940, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28556490

RESUMO

The extraction adsorbent was fabricated by immobilizing the highly specific recognition and binding of aptamer onto the surface of Fe3 O4 magnetic nanoparticles, which not only acted as recognition elements to recognize and capture the target molecule berberine from the extract of Cortex phellodendri, but also could favor the rapid separation and purification of the bound berberine by using an external magnet. The developed solid-phase extraction method in this work was useful for the selective extraction and determination of berberine in Cortex phellodendri extracts. Various conditions such as the amount of aptamer-functionalized Fe3 O4 magnetic nanoparticles, extraction time, temperature, pH value, Mg2+ concentration, elution time and solvent were optimized for the solid-phase extraction of berberine. Under optimal conditions, the purity of berberine extracted from Cortex phellodendri was as high as 98.7% compared with that of 4.85% in the extract, indicating that aptamer-functionalized Fe3 O4 magnetic nanoparticles-based solid-phase extraction method was very effective for berberine enrichment and separation from a complex herb extract. The applicability and reliability of the developed solid-phase extraction method were demonstrated by separating berberine from nine different concentrations of one Cortex phellodendri extract. The relative recoveries of the spiked solutions of all the samples were between 95.4 and 111.3%, with relative standard deviations ranging between 0.57 and 1.85%.


Assuntos
Berberina/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Nanopartículas de Magnetita , Phellodendron/química , Reprodutibilidade dos Testes , Extração em Fase Sólida
9.
Ying Yong Sheng Tai Xue Bao ; 27(1): 49-58, 2016 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-27228592

RESUMO

This study focused on retrieval of net photosynthetic rate (Pn) of moso bamboo forest based on analysis of wavelet transform on hyperspectral reflectance data of moso bamboo forest leaf. The result showed that the accuracy of Pn retrieved by the ideal high frequency wavelet vegetation index ( VI) was higher than that retrieved by low frequency wavelet VI and spectral VI. Normalized difference vegetation index of wavelet (NDVIw), simple ratio vegetation index of wavelet (SRw) and difference vegetation index of wavelet (Dw) constructed by the first layer of high frequency coefficient through wavelet decomposition had the highest relationship with Pn, with the R² of 0.7 and RMSE of 0.33; low frequency wavelet VI had no advantage compared with spectral VI. Significant correlation existed between Pn estimated by multivariate linear model constructed by the ideal wavelet VI and the measured Pn, with the R² of 0.77 and RMSE of 0.29, and the accuracy was significantly higher than that of using the spectral VI. Compared with the fact that sensitive spectral bands of the retrieval through spectral VI were limited in the range of visible light, the wavelength of sensitive bands of wavelet VI ranged more widely from visible to infrared bands. The results illustrated that spectrum of wavelet transform could reflect the Pn of moso bamboo more in detail, and the overall accuracy was significantly improved than that using the original spectral data, which provided a new alternative method for retrieval of Pn of moso bamboo forest using hyper spectral remotely sensed data.


Assuntos
Fotossíntese , Folhas de Planta/fisiologia , Poaceae/fisiologia , Análise de Ondaletas , Florestas , Luz , Modelos Lineares , Tecnologia de Sensoriamento Remoto , Análise Espectral
10.
Ying Yong Sheng Tai Xue Bao ; 27(12): 3797-3806, 2016 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-29704336

RESUMO

LAI is one of the most important observation data in the research of carbon cycle of forest ecosystem, and it is also an important parameter to drive process-based ecosystem model. The Moso bamboo forest (MBF) and Lei bamboo forest (LBF) were selected as the study targets. Firstly, the MODIS LAI time series data during 2014-2015 was assimilated with Dual Ensemble Kalman Filter method. Secondly, the high quality assimilated MBF LAI and LBF LAI were used as input dataset to drive BEPS model for simulating the gross primary productivity (GPP), net ecosystem exchange (NEE) and total ecosystem respiration (TER) of the two types of bamboo forest ecosystem, respectively. The modeled carbon fluxes were evaluated by the observed carbon fluxes data, and the effects of different quality LAI inputs on carbon cycle simulation were also studied. The LAI assimilated using Dual Ensemble Kalman Filter of MBF and LBF were significantly correlated with the observed LAI, with high R2 of 0.81 and 0.91 respectively, and lower RMSE and absolute bias, which represented the great improvement of the accuracy of MODIS LAI products. With the driving of assimilated LAI, the modeled GPP, NEE, and TER were also highly correlated with the flux observation data, with the R2 of 0.66, 0.47, and 0.64 for MBF, respectively, and 0.66, 0.45, and 0.73 for LBF, respectively. The accuracy of carbon fluxes modeled with assimilated LAI was higher than that acquired by the locally adjusted cubic-spline capping method, in which, the accuracy of mo-deled NEE for MBF and LBF increased by 11.2% and 11.8% at the most degrees, respectively.


Assuntos
Ciclo do Carbono , Florestas , Poaceae , Carbono , Árvores
11.
Fa Yi Xue Za Zhi ; 31(6): 466-9, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-27141807

RESUMO

Mild traumatic brain injury (MTBI) is defined as a mild brain trauma resulting in a short loss of consciousness and alteration of mental status. It may also occasionally develop persistent and progressive symptoms. It has been confirmed that MTBI causes changes of anatomic structures in central nervous system and biomarkers in the body fluid. However, there is no sufficient research on relevance among threshold for the brain injury, individual vulnerability and duration of disturbance of consciousness. Furthermore, there are no reliable diagnostic methods to establish whether a blow to the head is sufficient to cause the brain injury. This review provides references for biomarkers in cerebrospinal fluid and blood associated with TBI. It also provides application status and potential prospects for further assessment and diagnosis of MTBI.


Assuntos
Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Lesões Encefálicas/sangue , Lesões Encefálicas/líquido cefalorraquidiano , Concussão Encefálica/complicações , Lesões Encefálicas/diagnóstico , Lesões Encefálicas/etiologia , Progressão da Doença , Humanos
12.
Chin J Nat Med ; 11(3): 296-301, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23725845

RESUMO

AIM: To synthesize three novel esterified-derivatives of mangiferin and evaluate their hypoglycemic activities. METHODS: Acetic, propionic, and butyric anhydride were reacted with mangiferin, respectively. The hypoglycemic activity of the derivatives was evaluated using a hyperglycemic mouse model induced by streptozotocin (STZ), and the islet cells were checked by biopsy inspection. RESULTS: 7, 2', 3', 4', 6'-penta-acetyl-mangiferin (PAM), 3, 6, 7, 2', 3', 4', 6'-hepta-propionyl-mangiferin (HPM) and 3, 6, 7, 2', 3', 4'-hexa-butyryl-mangiferin (HBM) were synthesized and their structures were identified by MS,(1)H, (13)C NMR, and 2D NMR. These three compounds were reported for the first time. PAM group (0.5, 0.25 mmol·kg(-1)), HPM group (0.5, 0.25 mmol·kg(-1)), and HBM group (0.5, 0.25, 0.125 mmol·kg(-1)) mice showed strong hypoglycemic activity (P < 0.01); mangiferin group (1, 0.5 mmol·kg(-1)), PAM group (0.125 mmol·kg(-1)) and HPM group (0.125 mmol·kg(-1)) showed marginal hypoglycemic activity (P < 0.05); mangiferin group (0.25 mmol·kg(-1)) had the potential for a hypoglycemic effect, although it did not demonstrate that statistically. In histological examination, the islet cells of the PAM, HPM, and HBM groups could recover from the STZ damage; islet cells of the mangiferin group could recover also, but less than the esterified-derivative groups. CONCLUSION: Derivatives could repair the damaged islet cells, and had higher lipid-solubility and stronger hypoglycemic activity than mangiferin itself. There existed a structure activity effect, and a solubility effect relationship: the larger esterification moieties, or the higher lipid-solubility, the stronger the hypoglycemic activity (no ester → acetyl → propionyl → butyryl). Esterified derivatives of mangiferin are potential compounds for new anti-diabetes drugs.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/síntese química , Xantonas/administração & dosagem , Xantonas/síntese química , Animais , Esterificação , Humanos , Hipoglicemiantes/química , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Camundongos , Estrutura Molecular , Xantonas/química
13.
Zhongguo Zhong Yao Za Zhi ; 30(11): 842-4, 2005 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-16110867

RESUMO

OBJECTIVE: To study the hypoglycemic effect of the total flavonoids in Leucaena seeds(TF). METHOD: Experimental observation was performed by using various diabetic mice induced by alloxan, adrenalin, etc. RESULT: TF could significantly lower the blood glucose levels in Alloxan model mice, adrenalin model mice and hyperglycemic mice, while had no hypoglycemic effect on the normal mice. CONCLUSION: The total flavonoids in Leucaena seeds has hypoglycemic effect in diabetic model mice.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Fabaceae/química , Flavonoides/farmacologia , Hipoglicemiantes/farmacologia , Animais , Epinefrina , Flavonoides/isolamento & purificação , Hiperglicemia/sangue , Hiperglicemia/induzido quimicamente , Hipoglicemiantes/isolamento & purificação , Masculino , Camundongos , Plantas Medicinais/química , Sementes/química
14.
Zhongguo Zhong Yao Za Zhi ; 28(9): 839-41, 2003 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-15015377

RESUMO

OBJECTIVE: To develop a new method for determination of Mangiferin in the leafs of Folium mangiferae. By this new method, Mangiferin in F. mangiferae sampled in different months and in different regions was determinated. METHOD: A RP-HPLC method was set up, using Shim pack CLC-ODS column, methanol-0.05 mol.L-1 H3PO4(65:134, pH 3.5) as mobile phase, with 258 nm of detection wave, at room temperature, 1 mL.min-1. F. mangiferae sampled in Nanning, Qinzhou and Tianyang, Guangxi province and sampled respectively in January to December were determinated. RESULT: The average recovery of the RP-HPLC was 99.2%, RSD = 1.05% (n = 5). The content of Mangiferin in F. mangiferae was statistically different due to different sample-regions or sample-time. CONCLUSION: This RP-HPLC method is simple, specific and exact. The contents of Mangiferin in the leafs of F. mangiferae sample in Nanning and Tinayang were statistically similar, but higher than that in Qinzhou. The contents of Mangiferin in the leafs of F. mangiferae sampled in July to October were higher than that in the other months. The content in September was the highest, the content in February was the lowest.


Assuntos
Mangifera/química , Plantas Medicinais/química , Xantonas/análise , China , Cromatografia Líquida de Alta Pressão/métodos , Ecossistema , Folhas de Planta/química , Estações do Ano
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