Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Nat Prod ; 86(1): 119-130, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36579935

RESUMO

Nine new sesquiterpenes, hyperhubeins A-I (1-9), and 14 known analogues (10-23) were isolated from the aerial portions of Hypericum hubeiense. Their structures and absolute configurations were determined unambiguously via spectroscopic analysis, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Compounds 1-3 possess an unprecedented sesquiterpene carbon skeleton. Further, a plausible biosynthetic pathway from farnesyl diphosphate (FPP) is proposed. The isolated phytochemicals were evaluated for neuroprotective and anti-neuroinflammatory properties in vitro. Compounds 1, 2, 5-8, 14, and 21 displayed notable neuroprotective activity against hydrogen peroxide (H2O2)-induced lesions in PC-12 cells at 10 µM. Additionally, compounds 1, 2, 12, and 13 exhibited inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production in BV-2 microglial cells, with their IC50 values ranging from 4.92 to 6.81 µM. Possible interactions between these bioactive compounds and inducible nitric oxide synthase (iNOS) were predicted via molecular docking. Moreover, Western blotting indicated that compound 12 exerted anti-neuroinflammatory activity by suppressing LPS-stimulated expression of toll-like receptor-4 (TLR-4) and inhibiting consequent activation of nuclear factor-kappa-B (NF-κB) signaling.


Assuntos
Hypericum , Sesquiterpenos , Anti-Inflamatórios/química , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Peróxido de Hidrogênio , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , Microglia/metabolismo , Dicroísmo Circular , Óxido Nítrico , Óxido Nítrico Sintase Tipo II/metabolismo
2.
Phytochem Anal ; 33(3): 490-501, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35194875

RESUMO

INTRODUCTION: Forsythia suspensa (Thunb.) Vahl (FS), the fruit of Oleaceae plants, as a large part of traditional Chinese medicine, is classified as "Qingqiao (Q)" and "Laoqiao (L)" based on the harvest time. Because the maturation of FS is a gradual process, its accurate identification based on different maturity levels is an important issue. OBJECTIVES: We suggest colorimetric, electronic tongue, and high-performance liquid chromatography (HPLC) characteristic fingerprints to discriminate FS in different harvest periods. MATERIAL AND METHODS: First, FS fruits from different harvest times were collected, and then, their colour parameters, E-tongue sensory properties, HPLC characteristic fingerprints, and contents of nominal ingredients were determined. Finally, multivariate statistical analyses, including three-dimensional scatter plots, hierarchical cluster, principal component, linear discriminant, similarity, and partial least squares discriminant analyses were performed. RESULTS: The results demonstrated that the three experimental techniques could effectively discriminate FS based on different harvest times with 100% accuracy. Under the qualitative conditions, nine common peaks were identified in the HPLC fingerprints of 60 samples, among which, six peaks [variable importance in projection (VIP) > 1] could be used as index peaks for qualitative identification. In fact, the contents of quality marker components, including forsythin, phillygenin, rutin and forsythoside A, were significant different (P < 0.001) at different harvest times. Interestingly, the quality markers not only accurately reflected the maturity of FS but also showed close correlations with the colour parameters and sensory E-tongue responses. CONCLUSION: In our present investigation, bionic technologies, including a colorimeter, E-tongue analysis, and HPLC characteristic fingerprints, combined with chemometrics, were employed to develop a novel and accurate method for discriminating FS based on different harvest times.


Assuntos
Medicamentos de Ervas Chinesas , Forsythia , Quimiometria , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Forsythia/química , Frutas/química , Medicina Tradicional Chinesa
3.
Dalton Trans ; 49(42): 14995-15001, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33094765

RESUMO

The eCO2RR activity is correlated to the internal structural character of the catalyst. We employed two types of structural models of porphyrin-based MOFs of PCN-222(Cu) and PCN-224(Cu) into heterogeneous catalysis to illustrate the effect of structural factors on the eCO2RR performance. The composite catalyst PCN-222(Cu)/C displays better activity and selectivity (η = 450 mV, FEHCOOH = 44.3%, j = 3.2 mA cm-2) than PCN-224(Cu)/C (η = 450 mV, FEHCOOH = 34.1%, j = 2.4 mA cm-2) for the CO2 reduction to HCOOH in the range of -0.7--0.9 V (vs. RHE) due to its higher BET surface area, CO2 uptake, and a larger pore diameter. It is interesting that PCN-224(Cu)/C displays better performance in the range of -0.4--0.6 V (vs. RHE) due to its greater heat of adsorption, Qst and a higher affinity for CO2 molecule, which could promote the capture of CO2 onto the exposed active sites. As a result, PCN-224(Cu)/C exhibits better stability for the long-term electrolysis.

4.
J Photochem Photobiol B ; 207: 111869, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32278270

RESUMO

An animal laboratory in a teaching hospital is a possible cause of cross infection. We aimed to assess the infection control in our animal laboratory and evaluate the disinfectant effects of a portable pulsed xenon ultraviolet (PX-UV) machine. Samples were taken from the surface of research tables, other high touch places, such as doorknobs, weighing scales, and handles of trolleys, and from air in the barrier system pre- and post-manual cleaning and post-PX-UV disinfection. The bacteria types were identified. We found that routine manual cleaning significantly reduced bacterial colony form unit (CFU)/cm2 (P = .02), and the median of CFU/cm2 reduced from 0.5 pre-cleaning to zero post-cleaning. PX-UV disinfection also significantly reduced residual bacterial counts (P = .002), with the highest counts 10 pre-PX-UV disinfection and 1 afterwards. Without manual cleaning, PX-UV disinfected surfaces significantly (P < .001), median count 6 pre-PX-UV disinfection and zero afterwards. PX-UV significantly reduced bacterial colony counts in the air with the median count falling from 6 to zero (P < .001). Some of the 21 species of pathogens we identified in the current study are pathogenic, resistant to antibiotics, and able to cause nosocomial infections and zoonosis. PX-UV reduced counts of most of the pathogens. PX-UV is an effective agent against these pathogens.


Assuntos
Bactérias/efeitos da radiação , Infecção Hospitalar/prevenção & controle , Desinfecção/instrumentação , Desinfecção/métodos , Raios Ultravioleta , Xenônio/química , Animais , China , Contagem de Colônia Microbiana , Computadores de Mão , Relação Dose-Resposta à Radiação , Microbiologia Ambiental , Hospitais , Hospitais de Ensino , Humanos , Laboratórios
5.
Microbiol Immunol ; 60(8): 533-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27399903

RESUMO

Poultry husbandry is a very important aspect of the agricultural economy in China. However, chicks are often susceptible to infectious disease microorganisms, such as bacteria, viruses and parasites, causing large economic losses in recent years. In the present study, we isolated an Acinetobacter baumannii strain, CCGGD201101, from diseased chicks in the Jilin Province of China. Regression analyses of virulence and LD50 tests conducted using healthy chicks confirmed that A. baumannii CCGGD201101, with an LD50 of 1.81 (±0.11) × 10(4) CFU, was more virulent than A. baumannii ATCC17978, with an LD50 of 1.73 (±0.13) × 10(7) CFU. Moreover, TEM examination showed that the pili of A. baumannii CCGGD201101 were different from those of ATCC17978. Antibiotic sensitivity analyses showed that A. baumannii CCGGD201101 was sensitive to rifampicin but resistant to most other antibiotics. These results imply that A. baumannii strain CCGGD201101 had both virulence enhancement and antibiotic resistance characteristics, which are beneficial for A. baumannii survival under adverse conditions and enhance fitness and invasiveness in the host. A. baumannii CCGGD20101, with its high virulence and antimicrobial resistance, may be one of the pathogens causing death of diseased chicks.


Assuntos
Infecções por Acinetobacter/veterinária , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Doenças das Aves Domésticas/microbiologia , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Acinetobacter baumannii/ultraestrutura , Animais , China , Testes de Sensibilidade Microbiana , Fenótipo , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/mortalidade , Virulência
6.
J Asian Nat Prod Res ; 17(9): 867-75, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25996193

RESUMO

Four new iridoids (1, 2, 12, and 13), together with nine known iridoids (3-11), were isolated from the male flowers of Eucommia ulmoides Oliver and were characterized as 3ß-methoxyartselawnin C (1), 6ß-hydroxyl-1ß,3ß-dimethoxyartsclaenin III (2), 3,4-dihydro-3ß-ethoxyasperuloside (12) and 3,4-dihydro-3ß-ethoxydesacetylasperuloside (13) by extensive analyses of their 1D and 2D NMR spectroscopy and mass spectra. All of the isolated compounds were assayed for the promoting proliferation of skin fibroblasts cell (ESF-1) and compounds 4 and 7 (5 µM) significantly stimulated the proliferation of ESF-1 cells.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Eucommiaceae/química , Iridoides/isolamento & purificação , Iridoides/farmacologia , Extratos Vegetais/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Flores/química , Iridoides/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
7.
Artigo em Inglês | MEDLINE | ID: mdl-25600055

RESUMO

A protein with high purity has become an essential pre-requisite for investigating its bioactivity, molecular structure and characteristics. Therefore, the development of technologies for efficient purification of protein is urgently necessary. The objective of this study was to establish a purification protocol for a recombinant protein rG17PE38. Different forms of chromatography such as hydrophobic interaction and ion exchange chromatography were chosen as the core purification steps. The performance of each technique was optimized to meet the requirements and the purification steps were arranged in a logical way of facilitating to operate in next step. In addition, some characteristics of the protein such as stability, bioactivity and cellular location were determined. Finally, whether the protein could induce cell apoptosis was also explored. The results showed the protein purified via the suggested three-step purification scheme could obtain a purity of 95%, and its bioactivity in the form of IC50 was 17.6 ng/mL, furthermore it could keep stable at 4 °C for at least 10 days. The protein could bind on its target cell membrane specifically, and inducing cell apoptosis was demonstrated to be one of the cytotoxicity mechanisms of the protein. Results obtained in our study may provide useful information on strategies of protein purification and lay a substantial foundation for the followed animal or clinical experiments on rG17PE38.


Assuntos
Cromatografia por Troca Iônica/métodos , Proteínas Recombinantes/isolamento & purificação , Sulfato de Amônio , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Precipitação Química , Escherichia coli/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia
8.
Zhongguo Zhong Yao Za Zhi ; 39(21): 4225-9, 2014 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-25775798

RESUMO

Nine triterpenes compounds were isolated from the male flowers of Eucommia ulmoides by recrystallization and chromatographic techniques over silica gel, Sephadex LH-20, and RP-18 gel. Their chemical structures were identified on the basis of spectral analysis and as 3-oxo-12-en-ursane-28-O-α-L-arabinofuranosyl (1 --> 6) -ß-D-glucopyranoside (1), 2α, 3ß-dihydroxyurs-12-en-28-oic acid(28 --> 1) -ß-D-glucopyranosyl ester (2), ursolic acid (3), α-amyrin (4), uvaol (5), ursolic acid acetate (6), 3-O-acetate oleanoic acid (7), betulinic acid (8), and betulinol (9). Compound 1 was a new compound, and compounds 2, 4-7 were isolated from the Eucommiu genus for the first time. Cytotoxic activity was tested for all the compounds against K562 and HepG2 cells. The results showed that only compound 3, exhibited cytotoxic activity.


Assuntos
Eucommiaceae/química , Triterpenos/análise , Antineoplásicos Fitogênicos/farmacologia , Células Hep G2 , Humanos , Células K562 , Triterpenos/farmacologia
9.
Zhongguo Zhen Jiu ; 33(6): 533-7, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-23967645

RESUMO

OBJECTIVE: To observe the changes in the expression of neuroal nitric oxide synthase (nNOS) and glial fibrillary acidic protein (GFAP) in dentate gyrus (DG) of rats with Parkinson's disease (PD) and effects of electroacupuncture (EA). METHODS: On the 7th day of stereotactic injection with 6-hydroxydopamine into right medial forebrain bundle, apomorphine-induced rotation was carried out to select the PD rats. The selected 12 rats were randomly divided into a model group (n = 6) and an EA group (n = 6). Moreover a normal group was established (n = 6). Then, the rats in EA group were treated with EA at "Hegu" (LI 4) and "Taichong" (LR 3), once a day for 21 days, and the other groups without any treatment. After EA treatment, the expressions of nNOS and GFAP in right DG were examined by immunohistochemistry method. RESULTS: The expression of nNOS in the right DG was weak in normal group, and the expression of nNOS in model group was significantly higher than that in normal group (P < 0.01), while in EA group, it was significantly lower than that in model (P < 0.01), with no difference between EA group and normal group (P > 0.05). The expression level of GFAP in model group was significantly higher than that in normal group (P < 0.01), while there was no difference in the number of GFAP positive cells between the above two groups (P > 0.05), and the number of GFAP positive cells in EA group was significantly increased compared with that in model group (P < 0.01), while with no significant difference in the expression level of GFAP between EA group and model group (P > 0.05). CONCLUSION: EA can reverse the increase of nNOS expression and promote the activation of astrocyte in DG on the injured side in rats with PD.


Assuntos
Astrócitos/enzimologia , Giro Denteado/citologia , Eletroacupuntura , Óxido Nítrico Sintase/genética , Doença de Parkinson/terapia , Animais , Giro Denteado/enzimologia , Humanos , Masculino , Óxido Nítrico Sintase/metabolismo , Doença de Parkinson/enzimologia , Doença de Parkinson/genética , Ratos , Ratos Sprague-Dawley
10.
Zhen Ci Yan Jiu ; 37(4): 286-90, 2012 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-23140049

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) on the expression of proliferating cell nuclear antigen (PCNA) and glial fibrillary acidic protein (GFAP) in the subventricular zone (SVZ) of Parkinson's disease (PD) rats, so as to explore its mechanisms underlying improvement of PD. METHODS: Eighteen SD rats were randomized into normal control, model and EA groups (6 rats/group). PD model was duplicated by microinjection of 6-hydroxydopamine (2.5 microg/microL, 6 microL) containing 0.02% antiscorbic acid into the right medial forebrain bundle region (P: -4. 0, L: 0.8, H: 8.0). On the 7th day after modeling, EA (100 Hz) was applied to bilateral "Hegu" (LI 4) and "Taichong" (LR 3) for 30 min, once a day for 21 days. The expression levels of tyrosine hydroxylase (TH), GFAP and PCNA in the right SVZ tissue were detected by immunohistochemistry. RESULTS: TH expression was strong in the normal control group, but no TH expression was found in the model and EA groups. In comparison with the normal control group, the expression levels of PCNA and GFAP proteins and the number of PCNA-IR-positive cells in the right SVZ were decreased significantly in the model group (P < 0.01); while compared with the model group, the expression levels of PCNA and GFAP proteins and the number of PCNA-IR-positive cells in the right SVZ were up-regulated considerably in the EA group (P < 0.01, P < 0.05). CONCLUSION: EA can up-regulate the expression of PCNA and GFAP proteins in the SVZ in PD rats without changes of TH expression, which may contribute to its effect in improving clinical symptoms of PD.


Assuntos
Encéfalo/metabolismo , Eletroacupuntura , Proteína Glial Fibrilar Ácida/genética , Doença de Parkinson/genética , Doença de Parkinson/terapia , Antígeno Nuclear de Célula em Proliferação/genética , Animais , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Masculino , Doença de Parkinson/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos , Ratos Sprague-Dawley
11.
Neurochem Res ; 34(12): 2089-101, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19472051

RESUMO

We investigated the survival and the possible differentiation fate of the progenitors and immature neurons in the pars compacta of the substantia nigra (SNc) by intranigral injection of a glial cell line-derived neurotropic factor (GDNF) or glial cell line-derived neurotropic factor plus epidermal growth factor (EGF + GDNF) in 6-hydroxydopamine (6-OHDA)-lesioned rats. First, we performed behavioral tests by postural asymmetry and forelimb akinesia on the rats injected with 6-OHDA in striatumat day 7, and selected the qualified model according to the results. Then, intranigral GDNF or EGF + GDNF treatment was administered in the qualified PD model rats. On day 21, behavioral tests were performed with these rats; and then the rats were sacrificed for analyses of ß-tubulin isotype-III (Tuj1), nestin, glial fibrillary acidic protein (GFAP), and tyrosine hydroxylase (TH) by immunohistochemistry and Western blotting. The results indicated that GDNF could promote the survival of the progenitor cells and immature neurons in rat SNc following 6-OHDA lesion. Moreover, EGF is capable of enhancing the survival effect of GDNF on the progenitor cells and immature neurons in SNc. On day 21, rapid functional recovery from the lesion-induced behavioral asymmetries was observed in the GDNF or EGF + GDNF treated rats, and the numbers of TH-positive neurons increased in SNc, suggesting that the rats might generate new dopaminergic neurons. Thus, our study provides the new insight that the progenitors and immature neurons in SNc of 6-OHDA-lesioned rats might be able to differentiate toward the dopaminergic neurons fate subsequent to treatment with GDNF or EGF + GDNF.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Fator Neurotrófico Derivado de Linhagem de Célula Glial/farmacologia , Oxidopamina/toxicidade , Substância Negra/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Diferenciação Celular , Proteína Glial Fibrilar Ácida/biossíntese , Masculino , Células-Tronco Neurais , Neurônios/efeitos dos fármacos , Oxidopamina/farmacologia , Transtornos Parkinsonianos/fisiopatologia , Ratos , Ratos Sprague-Dawley , Células-Tronco/metabolismo , Substância Negra/citologia , Substância Negra/patologia , Tubulina (Proteína)/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...