Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Asian Nat Prod Res ; 26(1): 59-68, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38031435

RESUMO

A total of 65 phenolic acid compounds were annotated or identified by UHPLC-MS/MS method, among them, 17 p-HAP (p-hydroxyacetophenone) glycosides were firstly targeted profiled based on molecular networking. Their characteristic product ions of MS/MS spectra were found and examined on the guideline of targeted isolation. As a result, a new p-HAP glycoside was thus obtained and determined as 2'-O-caffeoyl-p-HAP-4-O-ß-D-glucopyranoside (33) based on 1D and 2D NMR data. Besides, multicomponents quantitative analysis indicated the distinct regional variability in chemicals distribution of A. japonica, and meanwhile, the contents of p-HAP glycosides from A. japonica were higher than those in A. capillaris as a whole, which further suggested the potential medicinal value of A. japonica.


Assuntos
Artemisia , Espectrometria de Massas em Tandem , Glicosídeos/química , Artemisia/química , Espectroscopia de Ressonância Magnética , Imageamento por Ressonância Magnética , Estrutura Molecular
2.
Stem Cell Rev Rep ; 18(6): 2137-2151, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34181185

RESUMO

Intestinal dysfunction is frequently driven by abnormalities of specific genes, microbiota, or microenvironmental factors, which usually differ across individuals, as do intestinal physiology and pathology. Therefore, it's necessary to develop personalized therapeutic strategies, which are currently limited by the lack of a simulated intestine model. The mature human intestinal mucosa is covered by a single layer of columnar epithelial cells that are derived from intestinal stem cells (ISCs). The complexity of the organ dramatically increases the difficulty of faithfully mimicking in vivo microenvironments. However, a simulated intestine model will serve as an indispensable foundation for personalized drug screening. In this article, we review the advantages and disadvantages of conventional 2-dimensional models, intestinal organoid models, and current microfluidic intestine-on-a-chip (IOAC) models. The main technological strategies are summarized, and an advanced microfluidic primary IOAC model is proposed for personalized intestinal medicine. In this model, primary ISCs and the microbiome are isolated from individuals and co-cultured in a multi-channel microfluidic chip to establish a microengineered intestine device. The device can faithfully simulate in vivo fluidic flow, peristalsis-like motions, host-microbe crosstalk, and multi-cell type interactions. Moreover, the ISCs can be genetically edited before seeding, and monitoring sensors and post-analysis abilities can also be incorporated into the device to achieve high-throughput and rapid pharmaceutical studies. We also discuss the potential future applications and challenges of the microfluidic platform. The development of cell biology, biomaterials, and tissue engineering will drive the advancement of the simulated intestine, making a significant contribution to personalized medicine in the future. Graphical abstract The intestine is a primary organ for digestion, absorption, and metabolism, as well as a major site for the host-commensal microbiota interaction and mucosal immunity. The complexity of the organ dramatically increases the difficulty of faithfully mimicking in vivo microenvironments, though physiological 3-dimensional of the native small intestinal epithelial tissue has been well documented. An intestinal stem cells-based microfluidic intestine-on-a-chip model that faithfully simulate in vivo fluidic flow, peristalsis-like motions, host-microbe crosstalk, and multi-cell type interactions will make a significant contribution.


Assuntos
Dispositivos Lab-On-A-Chip , Microfluídica , Humanos , Mucosa Intestinal , Intestinos , Medicina de Precisão
3.
Foods ; 10(11)2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34828932

RESUMO

Aristolochic acid (AA) toxicity has been shown in humans regarding carcinogenesis, nephrotoxicity, and mutagenicity. Monitoring the AA content in drug homologous and healthy foods is necessary for the health of humans. In this study, a monoclonal antibody (mAb) with high sensitivity for aristolochic acid I (AA-I) was prepared. Based on the obtained mAb, a chemiluminescent immunoassay (CLEIA) against AA-I was developed, which showed the 50% decrease in the RLUmax (IC50) value of 1.8 ng/mL and the limit of detection (LOD) of 0.4 ng/mL. Carbon dots with red emission at 620 nm, namely rCDs, were synthesized and employed in conventional indirect competitive enzyme-linked immunosorbent assay (icELISA) to improve the assay sensitivity of a fluoroimmunoassay (FIA). Oxidized 3,3'',5,5''-tetramethylbenzidine dihydrochloride (oxTMB) can quench the emission of the rCDs through the inner-filter effect; therefore, the fluorescence intensity of rCDs can be regulated by the concentration of mAb. As a result, the assay sensitivity of FIA was improved by five-fold compared to CLEIA. A good relationship between the results of the proposed assays and the standard ultra-high performance liquid chromatography-triple quadrupole mass spectrometer (UPLC-QQQ-MS/MS) of real samples indicated good accuracy and practicability of CLEIA and FIA.

4.
Eur J Med Chem ; 164: 706-716, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30677669

RESUMO

Considerable interest has been attracted in oleanolic acid and its analogues because of their hypoglycemic activity. In this study, a series of novel oleanolic acid analogues against α-glucosidase were synthesized and their biological activities were evaluated in vitro and in vivo. In vitro α-glucosidase inhibition activity results indicated that most of the designed analogues exhibited prominent inhibition activities, especially compounds 10, 15, 16 and 26 which with the IC50 values of 0.33 ±â€¯0.01, 0.98 ±â€¯0.06, 0.69 ±â€¯0.01 and 0.72 ±â€¯0.21 µM, respectively. Enzyme kinetic studies on the most potent compounds reveled that derivatives 10, 15, 16 and 26 were noncompetitive inhibitors. Moreover, the docking studies were carried out to prove that the four compounds could interact with the hydrophobic region of the active pocket and form hydrogen bonds to enhance the binding affinity of them with the α-glucosidase. Cytotoxicity evaluation assay demonstrated a high level of safety profile of the active compounds (10, 15, 16 and 26) against normal 3T3 cell line. Furthermore, the in vivo actual pharmacological potential studies on derivatives 10, 15, 16 and 26 showed that the hypoglycemic effects of them were comparable to that of positive control, acarbose.


Assuntos
Inibidores de Glicosídeo Hidrolases/síntese química , Ácido Oleanólico/farmacologia , alfa-Glucosidases/efeitos dos fármacos , Células 3T3 , Animais , Domínio Catalítico , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/farmacologia , Concentração Inibidora 50 , Camundongos , Simulação de Acoplamento Molecular , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Ligação Proteica
5.
Infect Drug Resist ; 11: 1945-1957, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30498366

RESUMO

BACKGROUND: Fusidic acid (FA) (WU-FA-00) is the only commercially available antimicrobial from the fusidane family that has a narrow spectrum of activity against Gram-positive bacteria. METHODS: Herein, the hydrogenation derivative (WU-FA-01) of FA was prepared and both compounds were examined against a panel of six bacterial strains. In addition, their anti-inflammatory properties were evaluated using a 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse ear edema model. RESULTS: The results of the antimicrobial assay revealed that both WU-FA-00 and WU-FA-01 displayed a high level of antimicrobial activity against Gram-positive strains. Moreover, killing kinetic studies were performed and the results were in accordance with the minimum inhibitory concentration and minimum bactericidal concentration results. We also demonstrated that the topical application of WU-FA-00 and WU-FA-01 effectively decreased TPA-induced ear edema in a dose-dependent manner. This inhibitory effect was associated with the inhibition of TPA-induced upregulation of proinflammatory cytokines IL-1ß, TNF-α, and COX-2. WU-FA-01 significantly suppressed the expression levels of p65, IκB-α, and p-IκB-α in the TPA-induced mouse ear model. CONCLUSION: Overall, our results showed that WU-FA-00 and WU-FA-01 not only had effective antimicrobial activities in vitro, especially to the Gram-positive bacteria, but also possessed strong anti-inflammatory effects in vivo. These results provide a scientific basis for developing FA derivatives as antimicrobial and anti-inflammatory agents.

6.
Sci Rep ; 7: 45578, 2017 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-28358057

RESUMO

Ursolic acid (UA) is a major pentacyclic triterpenoid in plants, vegetables and fruits, which has been reported to have a potential anti-diabetic activity. Despite various semi-synthetic ursolic acid derivatives already described, new derivatives still need to be designed and synthesized to further improve the anti-diabetic activity. In the present study, two series of novel UA derivatives, were synthesized and their structures were confirmed. The enzyme inhibition activities of semi-synthesized analogues against α-glucosidase were screened in vitro. The results indicated that most of UA derivatives showed a significant inhibitory activity, especially analogues UA-O-i with the IC50 values of 0.71 ± 0.27 µM, which was more potential than other analogues and the positive control. Furthermore, molecular docking studies were also investigated to verify the in vitro study. Structure modification at the C-3 and C-2 positions of UA was an effective approach to obtain the desired ligand from UA, whose structure was in accordance with the active pocket. Besides, suitable hydrophobic group at the position of C-2 might play an important role for the docking selectivity and binding affinity between the ligand and the homology modelling protein. These results could be helpful for designing more potential α-glucosidase inhibitors from UA in the future.


Assuntos
Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/síntese química , Hipoglicemiantes/farmacologia , Triterpenos/síntese química , Triterpenos/farmacologia , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Ácido Ursólico
7.
Bioorg Med Chem Lett ; 26(21): 5334-5339, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27680589

RESUMO

2-Substituted-1,4,5,6-tetrahydrocyclopenta[b]pyrrole, a key structural moiety exiting in many bioactive molecules, has been shown to have excellent selective activity on COX-2. In the present study, the anti-inflammatory activity and the underlying molecular mechanism of 2-substituted-1,4,5,6-tetrahydrocyclopenta[b]pyrrole on skin inflammation were assessed by 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin inflammation in mice. Most of the compounds showed anti-inflammatory activity on TPA-induced skin inflammation. The anti-inflammatory activity of compound 4 showed higher anti-inflammatory activity than celecoxib (3.2-fold). Compound 4 pretreatment resulted in markedly suppression of TPA-induced IL-1ß, IL-6, TNF-α, and COX-2, respectively. Furthermore, the mechanical study indicated that the anti-inflammatory activity of compound 4 was associated with its ability to inhibit activation of factor kappa-κB (NF-κB) by blocking IκB kinase (IKK) activities. Accordingly, compound 4 could be used as a potential anti-inflammatory agent for skin inflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Dermatite/prevenção & controle , Acetato de Tetradecanoilforbol/toxicidade , Animais , Ciclopentanos , Dermatite/etiologia , Camundongos , NF-kappa B/metabolismo , Pirróis
8.
Oncol Lett ; 11(6): 4160-4166, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27313760

RESUMO

The concentrations required for curcumin to exert its anticancer activity (IC50, 20 µM) are difficult to achieve in the blood plasma of patients, due to the low bioavailability of the compound. Therefore, much effort has been devoted to the development of curcumin analogues that exhibit stronger anticancer activity and a lower IC50 than curcumin. The present study investigated twelve pyridine analogues of curcumin, labeled as groups AN, BN, EN and FN, to determine their effects in CWR-22Rv1 human prostate cancer cells. The inhibitory effects of these compounds on testosterone (TT)-induced androgen receptor (AR) activity was determined by performing an AR-linked luciferase assay and by TT-induced expression of prostate-specific antigen. The results of the current study suggested that the FN group of analogues had the strongest inhibitory effect of growth on CWR-22Rv1 cultured cells, and were the most potent inhibitor of AR activity compared with curcumin, and the AN, BN and EN analogues. Thus, the results of the present study indicate the inhibition of the AR pathways as a potential mechanism for the anticancer effect of curcumin analogues in human prostate cancer cells. Furthermore, curcumin analogues with pyridine as a distal ring and tetrahydrothiopyran-4-one as a linker may be good candidates for the development of novel drugs for the treatment of prostate cancer, by targeting the AR signaling pathway.

9.
Food Chem ; 165: 560-8, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25038712

RESUMO

In this study, the essential oil from mustard seed was isolated by simultaneous steam distillation and extraction (SDE) and analyzed by gas chromatography-mass spectrometry (GC-MS). Fourteen components were identified in the mustard seed essential oil with allyl isothiocyanate being the main component (71.06%). The essential oil has a broad-spectrum antimicrobial activity with inhibition zones and MIC values in the range of 9.68-15.57 mm and 128-512 µg/mL respectively. The essential oil was subsequently encapsulated in complex coacervation microcapsules with genipin, a natural water-soluble cross-linker. The optimum parameters for the hardening effectiveness of the genipin-hardened essential oil microcapsules were 8h at 40°C and pH 10.0 with a genipin concentration of 0.075 g/g gelatin. The genipin-hardened microcapsules had a particle size of mainly 5-10 µm and strong chemistry stability which is potential for its application in food preservation.


Assuntos
Antibacterianos/farmacologia , Composição de Medicamentos/métodos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Óleos Voláteis/química , Sementes/química , Sinapis/química , Ágar/química , Cápsulas , Destilação , Cromatografia Gasosa-Espectrometria de Massas , Gelatina/análise , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Extratos Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
10.
Eur J Med Chem ; 80: 502-8, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24813878

RESUMO

In this study, a series of ursolic acid derivatives were synthesized, and their structures were confirmed. The activity of the synthesized compounds against α-glucosidase was determined in vitro. The results suggested that all compounds have significant inhibitory activity, especially compounds 3-5 and 8, the IC50 values of which were 2.66 ± 0.84, 1.01 ± 0.44, 3.26 ± 0.22, and 3.24 ± 0.21 µM. These compounds were more potent than acarbose (positive control) against α-glucosidase. Kinetic studies were performed to determine the mechanism of inhibition by compounds 3-5 and 8. The kinetic inhibition studies indicated that compound 3 was a non-competitive inhibitor, and the inhibition constant Ki was calculated to be 2.67 ± 0.19 µM. Moreover, the kinetic inhibition studies of compounds 4, 5 and 8 demonstrated that they were mixed-type inhibitors. Furthermore, the actual pharmacological potentials of synthesized compounds 3 and 4 were demonstrated by the reduction of postprandial blood glucose levels in normal Kunming mice. The hypoglycemic effects of these compounds were more evident 30 and 60 min after maltose ingestion (P < 0.05), which was similar to the effect displayed by the positive control, acarbose.


Assuntos
Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Triterpenos/química , Triterpenos/farmacologia , Animais , Glicemia/metabolismo , Cinética , Camundongos , alfa-Glucosidases/metabolismo , Ácido Ursólico
11.
Chemosphere ; 95: 105-10, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24034823

RESUMO

Bisphenol A (BPA) is a ubiquitous environmental contaminant in food products and aquatic ecosystems. Its endocrine and developmental toxicity presents a serious concern to human health and an effective high-throughput method for its detection is desirable. In this paper, water-soluble quantum dots (QDs) have been conjugated covalently with BPA antibodies and the conjugate has been utilized in a competitive fluorescence-linked immunoassay (FLISA). Cd-doped ZnO QDs were functionalized with poly(amidoamine) (PAMAM) dendrimers, as evidenced by ultraviolet absorption spectrum and fluorescence emission spectra analyses, and this led to their successful transfer into aqueous solution. Biological mass spectrometry demonstrated that the bisphenol A antibodies were successfully coupled to the water-soluble QDs, and the structures of these conjugates kept intact. The FLISA method allowed for BPA determination in a linear working range of 20.8-330.3 ng mL(-1) with the limit of detection (LOD) of 13.1 ng mL(-1). The recoveries of BPA from water samples were from 85.92% to 109.62%. In conclusion, a rapid and sensitive FLISA was developed by utilizing novel QD coupling method and validated for use in aqueous samples.


Assuntos
Compostos Benzidrílicos/análise , Cádmio/química , Imunoensaio/métodos , Fenóis/análise , Pontos Quânticos/química , Poluentes Químicos da Água/análise , Óxido de Zinco/química , Anticorpos/química , Compostos Benzidrílicos/química , Humanos , Limite de Detecção , Fenóis/química , Poluentes Químicos da Água/química
12.
Chem Pharm Bull (Tokyo) ; 61(11): 1149-55, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23985704

RESUMO

Eleven curcumin-related compounds containing a benzyl piperidone moiety were synthesized and evaluated for their effects on cultured prostate cancer PC-3 cells, pancreas cancer BxPC-3 cells, colon cancer HT-29 cells and lung cancer H1299 cells. Inhibitory effects of these compounds on the growth of PC-3, BxPC-3, HT-29 and H1299 cells were determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and trypan blue exclusion assay. Compounds benzyl piperidone 2 (P2), P4, P7, 4-bromo-2-fluoro-benzyl piperidone 2 (PFBr2), PFBr3 and PFBr4 (see syntheses and structures in Figs. 1, 2) exhibited potent inhibitory effects on the growth of cultured PC-3, BxPC-3, HT-29 and H1299 cells. The IC50 for these compounds was lower than 2 µM in all four cell lines. PFBr4 was 41-, 36-, 40- and 46-fold more active than curcumin for inhibiting the growth of PC-3, BxPC-3, HT-29 and H1299 cells, respectively. The benzyl piperidone-containing compounds studied also stimulated apoptosis in PC-3 cells. Mechanistic studies indicate that the effects of both curcumin and PFBr4 on PC-3 cells were associated with a decrease in phospho-Akt and phospho-extracellular signal-regulated kinase (Erk)1/2. The present study indicates that P2, P4, P7, PFBr2, PFBr3 and PFBr4 may have useful effects on human cancer cells.


Assuntos
Antineoplásicos/síntese química , Curcumina/análogos & derivados , Piperidonas/química , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Curcumina/toxicidade , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Relação Estrutura-Atividade
13.
Nanoscale Res Lett ; 7(1): 405, 2012 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-22809232

RESUMO

In the present work, ZnO quantum dots (QDs) have been prepared by the sol-gel method, and the performance of the QDs has been improved. The effect of Cd concentration on the structural and luminescent properties of the QDs, as well as the effect of the mass ratio of trioctylphosphine oxide (TOPO)/octadecylamine (ODA), has been investigated. The ZnO and Cd-doped ZnO QDs have hexagonal wurtzite structures and are 3 to 6 nm in diameter. When the Cd content was increased, the QD particle size was reduced; this effect was confirmed in the corresponding ultraviolet-visible spectra. The fluorescence intensity was simultaneously enhanced significantly. Both the UV and fluorescence spectra were blue-shifted. The luminous intensity was further enhanced when the QDs were modified with TOPO/ODA. Fourier transform infrared and X-ray diffraction techniques proved that the polymer successfully coated the surfaces of the QDs. A TOPO/ODA mass ratio of 1:2 was determined to result in the best optical performance among the different ratios examined. The results showed that the described synthetic method is appropriate for the preparation of doped QDs with high-fluorescence quantum efficiency.

14.
Zhong Yao Cai ; 35(2): 304-6, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22822679

RESUMO

OBJECTIVE: To investigate the technology of Aucubin in Eucommia ulmoides leaves extracted by enzymatic method and its antibacterial activity. METHODS: Aucubin in Eucommia ulmoides leaves was extracted by cellulase method. The extraction technology was optimized using the content of Aucubin as index. The antibacterial activity of Aucubin was determined. RESULTS: The results showed that the optimum technology was as follows; The solid-liquid ratio was 1:12, extracted for 50 min by 0.4% enzyme at 50 degrees C in pH 6.0. The extraction rate of Aucubin was as high as 17.892 mg/g. The Aucubin extracted could obviously inhibit the growth of Escherichia coli and Staphylococcus aureus, the MIC of Aucubin against Staphylococcus aureus and Escherichia coli were 4.832 mg/mL and 9.664 mg/mL respectively. However, Aucubin presented weak inhibitory effect on Streptococcus pneumonia and MG-hemolytic streptococcus, the MIC of Aucubin against them were all 28.946 mg/mL. CONCLUSION: The extraction technology obtained in this experiment is reasonable and feasible with high extraction rate, and the Aucubin has some antibacterial activity.


Assuntos
Antibacterianos/farmacologia , Eucommiaceae/química , Glucosídeos Iridoides/isolamento & purificação , Glucosídeos Iridoides/farmacologia , Folhas de Planta/química , Antibacterianos/isolamento & purificação , Celulase/metabolismo , Escherichia coli/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Hidrólise , Glucosídeos Iridoides/química , Plantas Medicinais/química , Staphylococcus aureus/efeitos dos fármacos , Tecnologia Farmacêutica/métodos , Temperatura
15.
Zhong Yao Cai ; 34(12): 1940-2, 2011 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-22500434

RESUMO

OBJECTIVE: To optimize the extraction technology of total flavonoids and improve the extraction ratio of total flavonoids from Selaginella uncinata. METHODS: Using the content of flavonoids as the index determined by UV spectrophotometry, chose single factor experiment to investigate the total flavonoids content influenced by four factor ethanol concentration, extracting time, extraction times and solvent content on the influence of extraction efficiency. And on the basis, L9 (3(4)) orthogonal experiment was carried out. RESULTS: The ethanol reflux extraction conditions were as tollows: extracted in 60% ethanol (solid-liquid rate at 1: 35) for 3 times and heated for 1.5 hours per time. CONCLUSION: The optimum extraction by the orthogonal design method is rational and feasible, provides experimental basis for improving the content of the total flavonoids and further scientific theoretical basis for industrial production of the total flavonoids from Selaginella uncinata.


Assuntos
Flavonoides/isolamento & purificação , Plantas Medicinais/química , Selaginellaceae/química , Tecnologia Farmacêutica/métodos , Etanol/química , Quercetina/química , Solventes/química , Espectrofotometria Ultravioleta , Fatores de Tempo
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(12): 3362-5, 2011 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-22295795

RESUMO

Cd-Zn quantum dots (QDs) modified with thiourea was firstly prepared asthe cores, then the cores were coated with polyacrylic acid with PVP K-30 as the stabilizer in water-soluble reaction system. The water-soluble fluorescence QDs were the same size and stable. The water-soluble QDs were characterized by fluorescence emission spectra, infrared spectra (IR), and transmission electron microscopy (TEM). The effects of the nuclear QDs with different concentration under polyacrylic acid solution on the optical properties of QDs were also studied. The results showed that the nanoparticles of QDs modified with polyacrylic acid have more uniform particle distribution, and the main peak was blueshifted from 548 to 448 nm. C==O and C--O stretching vibration absorption peaks were 2092.8 and 1384.3 cm(-1) in infrared spectra, amide bond of C==O stretching vibration absorption peaks were 1644.5 cm(-1). The best concentration of nuclear QDs under polyacrylic acid solution was 2.67 mg x mL(-1). QDs prepared by this simple method have good stability and strong fluorescence intensity. The approach introduced in this paper will lay a solid foundation for biological markers and applications of QDs in the future.

17.
Zhong Yao Cai ; 33(5): 724-6, 2010 May.
Artigo em Chinês | MEDLINE | ID: mdl-20873555

RESUMO

OBJECTIVE: To isolate and identify the chemical constituents from the active section with lowering blood sugar of agrimony. METHODS: The compounds were separated by repeated silica gel, polyamide and HPLC chromatographies. The structures of compounds isolated were identified by analysis of their spectral data and chemical peoperties. RESULTS: Nine compounds were isolated from the active section with lowering blood sugar of agrimony and their structures were identified as oleanoic acid (1), ursolic acid (2), 19alpha-hydroxy ursolic acid (3), tormentic acid (4), apigenin (5) , luteolin (6), kaempferol (7), 3,3'-di-O-methyl ellagic acid (8), kaempferol-7-O-alpha-L-rhamnoside (9). CONCLUSION: Compounds 1-3, 8, 9 are isolated from Agrimony for the first time.


Assuntos
Agrimonia/química , Hipoglicemiantes/isolamento & purificação , Ácido Oleanólico/análogos & derivados , Plantas Medicinais/química , Saponinas/isolamento & purificação , Triterpenos/isolamento & purificação , Apigenina/química , Apigenina/isolamento & purificação , Ácido Elágico/análogos & derivados , Ácido Elágico/química , Ácido Elágico/isolamento & purificação , Hipoglicemiantes/química , Luteolina/química , Luteolina/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ácido Oleanólico/química , Ácido Oleanólico/isolamento & purificação , Componentes Aéreos da Planta/química , Saponinas/química , Triterpenos/química , Ácido Ursólico
18.
Zhong Yao Cai ; 32(7): 1028-30, 2009 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-19873727

RESUMO

OBJECTIVE: To determine the contents of gastrodin, amino acids and total flavonoids in wild and cultivated Gastrodia elata, in order to choose the best method for its cultivation. The Gastrodia elata was picked at Guxiang town Bomi county Linzhi Region in Tibet. METHODS: HPLC was used to determine the content of gastrodin. The autoanalyzer was used to determine the content of amino acid. The ultraviolet spectrophotometer was adopted to measure the content of total flavonoids. RESULTS: The Gastrodin in wild Gastrodia elata was the highest. The contents of amino acids and total flavonoids in organic cultivated Gastrodia elata were higher than those in common cultivated and wild Gastrodia elata. CONCLUSION: The organic cultivated Gastrodia elata has better quality.


Assuntos
Aminoácidos/análise , Álcoois Benzílicos/análise , Flavonoides/análise , Gastrodia/química , Glucosídeos/análise , Plantas Medicinais/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Fertilizantes , Gastrodia/classificação , Gastrodia/crescimento & desenvolvimento , Plantas Medicinais/classificação , Plantas Medicinais/crescimento & desenvolvimento , Espectrofotometria Ultravioleta
19.
Biomed Environ Sci ; 22(3): 237-43, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19725467

RESUMO

OBJECTIVE: To prepare artificial antigens and anti-citrinin egg yolk-derived immunoglobulin (IgY) to build an enzyme-linked immunosorbent assay (ELISA) for citrinin (CTN). METHODS: CTN was conjugated with bovine serum albumin (BSA), ovalbumin (OVA) with formaldehyde condensation method to prepare artificial antigens and identified by ultraviolet (UV) spectrometry and Infrared (IR) spectrometry. Artificial antigens for CTN and anti-CTN IgY were purified with polyethylene glycol two-step precipitation method and identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). ELISA with IgY was established. Cross-reactivity of IgY with various structural similarities to CTN and possible co-occurrence with CTN in agricultural commodities were studied. RESULTS: UV and IR absorption spectra suggested that CTN was correlated with the carrier protein of BSA or OVA. SDS-PAGE patterns showed that the anti-CTN IgY was almost pure with a molecular weight of approximate 100 KD. The indirect competitive ELISA showed that the detection limit of CTN was 10 ng x mL(-1), with a good linearity ranging 20-640 ng x mL(-1). CONCLUSION: Artificial antigens of CTN can be successfully synthesized. The established ELISA can be used to determine CTN- contaminated samples.


Assuntos
Antígenos/química , Citrinina/química , Gema de Ovo/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulinas/imunologia , Animais , Especificidade de Anticorpos , Galinhas , Feminino
20.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): o1926, 2009 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-21583609

RESUMO

In the cation of the title compound, C(7)H(7)N(4)O(2) (+)·Cl(-), the benzimidazole ring system is planar with a maximum deviation of -0.019 (3) Å. In the crystal structure, C-H⋯Cl, N-H⋯Cl, and N-H⋯Cl inter-actions link the mol-ecules into a two-dimensional network. π-π contacts between benzimidazole rings [centroid-centroid distances = 3.928 (1) and 3.587 (1) Å] may further stabilize the structure.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...