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1.
Dalton Trans ; 53(5): 2120-2130, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38180436

RESUMO

To tackle the obstacles related to tumor targeting and overcome the limitations of single treatment models, we have developed a nanoplatform that is both tumor-targeted and enzyme-responsive. This nanoplatform integrates photothermal gold nanorods (AuNRs) and protein drugs into a single system. This nanosystem, known as AuNRs@HA-mPEG-Deta-LA, was fabricated by modifying gold nanorods (AuNRs) with a polymeric ligand called hyaluronic acid-grafted-(mPEG/diethylenetriamine-conjugated-lipoic acid). The purpose of this fabrication was to load cytochrome c (CC) and utilize it for the synergetic protein-photothermal therapy of cancer. The resulting nanoplatform exhibited a high efficiency in loading proteins and demonstrated excellent stability in different biological environments. Additionally, CC-loaded AuNRs@HA-mPEG-Deta-LA not only enabled localized hyperthermia for photothermal therapy (PTT) with laser irradiation but also facilitated the release of CC under the action of hyaluronidase, an enzyme known to be overexpressed in tumor cells. The confocal imaging results demonstrated that the presence of a specific polymeric ligand on this nanoparticle enhances the internalization of CD44-positive cancer cells, accelerates endo/lysosomal escape, and facilitates the controlled release of CC within the cells. Furthermore, the results of the MTT assay also showed that AuNRs@HA-mPEG-Deta-LA as a protein nanocarrier demonstrated excellent biocompatibility. Importantly, this synergistic therapeutic strategy effectively induced apoptosis in A549 cancer cells by increasing the intracellular concentration of CC and utilizing the photothermal conversion of AuNRs, which was observed to be more effective compared to using only protein therapy or PTT. Therefore, this study showcased a nanoplatform based on AuNRs that has great potential for tumor-targeted protein delivery in combination with PTT in cancer treatment.


Assuntos
Hipertermia Induzida , Nanotubos , Neoplasias , Polietilenoglicóis , Humanos , Fototerapia , Terapia Fototérmica , Ouro/farmacologia , Ligantes , DEET , Neoplasias/terapia , Neoplasias/patologia , Lisossomos , Linhagem Celular Tumoral
2.
Biotechnol Bioeng ; 120(8): 2333-2344, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37288610

RESUMO

Au nanorods (AuNRs) have attracted considerable interest as drug delivery systems because of their enhanced cell internalization and stronger drug-loading ability. In addition, the incorporation of photodynamic therapy (PDT) and photothermal therapy (PTT) into one nanosystem presents great promise to defect multiple drawbacks in cancer therapy. Herein, we fabricated a multifunctional and dual-targeting nanoplatform based on hyaluronic acid-grafted-(mPEG/triethylenetetramine-conjugated-lipoic acid/tetra(4-carboxyphenyl)porphyrin/folic acid) polymer ligand capped AuNRs (AuNRs@HA-g-(mPEG/Teta-co-(LA/TCPP/FA)) for combined photodynamic-photothermal therapy of cancer. The prepared nanoparticles displayed high TCPP loading capacity and excellent stability in different biological media. Furthermore, AuNRs@HA-g-(mPEG/Teta-co-(LA/TCPP/FA)) not only could produce a localized hyperthermia to conduct PTT, but also generate cytotoxic singlet oxygen (1 O2 ) to perform PDT under laser irradiation. Confocal imaging results disclosed that this nanoparticle endowing the specific function of polymeric ligand could enhance cellular uptake, accelerate endo/lysosomal escape, as well as produce higher reactive oxygen species. Importantly, this combination therapy strategy could also induce higher anticancer potential than PDT or PTT only against MCF-7 tumor cells in vitro. Therefore, this work presented an AuNRs-based therapeutic nanoplatform with great potential in dual-targeting and photo-induced combination therapy of cancer.


Assuntos
Nanopartículas , Nanotubos , Neoplasias , Fotoquimioterapia , Humanos , Ácido Hialurônico , Ouro/farmacologia , Terapia Fototérmica , Ligantes , Polímeros , Lisossomos , Linhagem Celular Tumoral
3.
Nat Prod Res ; 29(4): 327-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25109635

RESUMO

In this study, paclitaxel, baccatin III, taxuyunnanine C and sinenxane C were successfully separated by reversed-phase flash chromatography on a manually packed C18 column from Taxus chinensis cell culture extract. The crude cell culture extract was first treated with Al2O3 column chromatography and then divided into two parts: fraction 1 and fraction 2. Ten milligrams of baccatin III and 19 mg of paclitaxel were obtained from 100 mg dried fraction 1. Fifty-two milligrams of taxuyunnanine C and 11 mg sinenxane C were obtained from 100 mg dried fraction 2. The purities of the four compounds were 98.02%, 98.53%, 98.93% and 98.76%, respectively. Their structures were characterised by using UV, MS and NMR. These results indicate that paclitaxel and related taxanes including baccatin III can be obtained from cell culture in a highly pure state using reversed-phase flash chromatography.


Assuntos
Paclitaxel/isolamento & purificação , Taxoides/isolamento & purificação , Taxus/química , Alcaloides/isolamento & purificação , Técnicas de Cultura de Células , Cromatografia de Fase Reversa , Extratos Vegetais/química
4.
Nat Prod Res ; 29(12): 1139-44, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25427246

RESUMO

A new bibenzyl derivative (1), 4-acetoxy-3,5,3',4'-tetramethoxybibenzyl, along with eight known compounds (2-9), was isolated from the twigs and leaves of Schefflera arboricola (Araliaceae). The isolated compounds were elucidated mainly by means of one-dimensional, two-dimensional NMR and MS, and by comparison with the literature data. Compounds 2-5 and 7-9 are first reported from this plant. In the in vitro assays, compound 1 displayed moderate nuclear factor-kappaB inhibitory activity.


Assuntos
Araliaceae/química , Bibenzilas/química , NF-kappa B/antagonistas & inibidores , Animais , Linhagem Celular , Camundongos , Estrutura Molecular , Folhas de Planta/química , Caules de Planta/química
6.
Nat Prod Res ; 28(9): 674-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24650293

RESUMO

Orientin and vitexin are the two main bioactive compounds in Trollius chinensis Bunge. In this study, a rapid method was established for the isolation and purification of orientin and vitexin from T. chinensis Bunge using high-speed counter-current chromatography in one step, with a solvent system of ethyl acetate-ethanol-water (4:1:5, v/v/v). A total of 9.8 mg orientin and 2.1 mg vitexin were obtained from 100 mg of the ethyl acetate extract, with purities of 99.2% and 96.0%, respectively. Their structures were identified by UV, MS and NMR. The method was efficient and convenient, which could be used for the preparative separation of orientin and vitexin from T. chinensis Bunge.


Assuntos
Apigenina/isolamento & purificação , Flavonoides/isolamento & purificação , Glucosídeos/isolamento & purificação , Ranunculaceae/química , Apigenina/análise , Apigenina/química , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Flavonoides/análise , Flavonoides/química , Glucosídeos/análise , Glucosídeos/química , Ressonância Magnética Nuclear Biomolecular
7.
Phytochem Anal ; 25(3): 266-72, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24497376

RESUMO

INTRODUCTION: Poplar tree gum has a similar chemical composition and appearance to Chinese propolis (bee glue) and has been widely used as a counterfeit propolis because Chinese propolis is typically the poplar-type propolis, the chemical composition of which is determined mainly by the resin of poplar trees. The discrimination of Chinese propolis from poplar tree gum is a challenging task. OBJECTIVE: To develop a rapid thin-layer chromatographic (TLC) identification method using chemometric fingerprinting to discriminate Chinese propolis from poplar tree gum. METHODS: A new TLC method using a combination of ammonia and hydrogen peroxide vapours as the visualisation reagent was developed to characterise the chemical profile of Chinese propolis. Three separate people performed TLC on eight Chinese propolis samples and three poplar tree gum samples of varying origins. Five chemometric methods, including similarity analysis, hierarchical clustering, k-means clustering, neural network and support vector machine, were compared for use in classifying the samples based on their densitograms obtained from the TLC chromatograms via image analysis. RESULTS: Hierarchical clustering, neural network and support vector machine analyses achieved a correct classification rate of 100% in classifying the samples. A strategy for TLC identification of Chinese propolis using chemometric fingerprinting was proposed and it provided accurate sample classification. CONCLUSION: The study has shown that the TLC identification method using chemometric fingerprinting is a rapid, low-cost method for the discrimination of Chinese propolis from poplar tree gum and may be used for the quality control of Chinese propolis.


Assuntos
Cromatografia em Camada Fina/métodos , Populus/química , Própole/isolamento & purificação , Resinas Vegetais/isolamento & purificação , Animais , Abelhas , Análise por Conglomerados , Mapeamento de Peptídeos , Própole/química , Resinas Vegetais/química , Árvores
8.
J Anal Methods Chem ; 2013: 827361, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23738236

RESUMO

A simple and efficient HPLC-DAD (225 nm) method was developed and validated for the simultaneous determination of limonin and six key alkaloids (evodiamine, rutaecarpine, 1-methyl-2-undecyl-4(1H)-quinolone, evocarpine, 1-methy-2-[(6Z,9Z)]-6,9-pentadecadienyl-4-(1H)-quinolone, and dihydroevocarpine) in Evodia rutaecarpa (Juss.) Benth, which has been widely used as one of the Traditional Chinese Medicines. The chromatographic separation was carried out on a Hypersil BDS C18 column, and gradient elution was employed with a mobile phase containing acetonitrile and water. Contents of the analytes in 18 batches of samples were analyzed by ultrasonic extraction with ethanol and water mixture (80 : 20, v/v) followed by HPLC analysis. Separation of the seven analytes was achieved within 60 min with good linearity (r > 0.999). The RSD of both the intraday and interday precision was below 1.85%. The accuracy at different concentrations was within the range of 97.91 to 100.49%. Hierarchical clustering analysis was performed to differentiate and classify the samples based on the contents of the seven constituents. This study indicated that the quality control of E. rutaecarpa could be simplified to the measurement of four constituents, and that limonin, 1-methyl-2-undecyl-4(1H)-quinolone, and dihydroevocarpine should also be served as the chemical markers together with evodiamine for the quality control of Evodia rutaecarpa (Juss.) Benth.

9.
J Pharm Anal ; 3(3): 215-220, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29403820

RESUMO

Volatile components from Rhizoma Alpiniae Officinarum were respectively extracted by three methods including hydrodistillation, headspace solid-phase microextraction (HS-SPME) and diethyl ether extraction. A total of 40 (hydrodistillation), 32 (HS-SPME) and 37 (diethyl ether extraction) compounds were respectively identified by gas chromatography-mass spectrometry (GC/MS) and 22 compounds were overlapped, including α-farnesene, γ-muurolene, 2,6-dimethyl-6-(4-methyl-3-pentenyl)bicyclo[3.1.1]hept-2-ene, eucalyptol and cadina-1(10), 4-diene and so forth, varying in relative contents. HS-SPME is fast, sample saving and solvent-free and it also can achieve similar profiles as those from hydrodistillation and solvent extraction. Therefore, it can be the priority for extracting volatile components from medicinal plants.

10.
J Pharm Anal ; 3(6): 429-433, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29403850

RESUMO

A high-speed counter-current chromatography (HSCCC) method was successfully developed for the preparative separation and purification of deoxyschizandrin from Schisandrae Sphenantherae Fructus in one step. The purity of deoxyschizandrin was 98.5%, and the structure was identified by MS, UV and NMR. This method was simple, fast, convenient and appropriate to prepare pure compound as reference substances for related research on Schisandrae Sphenantherae Fructus.

11.
J Pharm Anal ; 3(6): 456-459, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29403855

RESUMO

Heteroclitin D (H.D) was successfully isolated from Kadsurae Caulis by using flash chromatography and recrystallized by methanol, 10.2 mg of H.D was obtained from 4.86 g of crude extract, and the purity determined by HPLC was 99.4%. The structure was identified by UV, IR, MS, and NMR analysis. The fast, simple and efficient method can be applied to the preparation of reference substance of H. D.

12.
J Pharm Anal ; 2(4): 258-263, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29403751

RESUMO

An efficient method for the isolation and purification of 12,13-dihydroxyeuparin from Radix Eupatorii Chinensis by high speed counter-current chromatography (HSCCC) was established in this paper. The ether extracts of Radix Eupatorii Chinensis were purified by HSCCC with a solvent system of hexyl hydride-ethyl acetate-methanol-water (1:2:1:2, v/v/v/v). The upper phase was used as the stationary phase and the lower phase as the mobile phase. About 8.4 mg of 12,13-dihydroxyeuparin was obtained from 200 mg of ether extracts from Radix Eupatorii Chinensis in one-step HSCCC separation, with the purity of 96.71%, as determined by HPLC. After methanol-water recrystallization, the purity of 12,13-dihydroxyeuparin reached 99.83%. Such a simple and effective method was fairly useful to prepare pure compound as reference substances for related study on Radix Eupatorii Chinensis.

13.
J Pharm Anal ; 1(3): 219-222, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29403703

RESUMO

A reversed phase high performance liquid chromatography (HPLC) method was established for the simultaneous determination of 12, 13-dihydroxyeuparin and glycyrrhizic acid in Yanyanfang mixture. A Grace Apollo C18 column (250 mm×4.6 mm, 5 µm) was used as the stationary phase and the mobile phase was composed of acetonitrile and aqueous phosphoric acid (0.2%, v/v). Gradient elution was carried out at the flow rate of 1.0 mL/min and the column temperature was 30 °C. An ultraviolet (UV) detector was used with a selected wavelength of 240 nm. Calibration curves were linear within the concentration range of 4.6-45.75 µg/mL for 12, 13-dihydroxyeuparin (r>0.9999) and 106.9-1068.9 µg/mL for glycyrrhizic acid (r>0.9999), respectively. Recoveries were 102.18% for 12, 13-dihydroxyeuparin and 101.17% for glycyrrhizic acid. The method developed could be applied to the simultaneous determination of 12, 13-dihydroxyeuparin and glycyrrhizic acid in Yanyanfang mixture.

14.
Nat Prod Res ; 24(19): 1854-60, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21104532

RESUMO

A silica gel column chromatography method is established for the isolation and purification of euparin and 12,13-dihydroxyeuparin from Radix Eupatorii Chinensis. For the first time, a high-performance liquid chromatography (HPLC) method is developed to determine simultaneously two benzofurans with UV absorptions at 240 nm. The analysis is performed on a Diamonsil C18 column with a gradient solvent system of acetonitrile and aqueous phosphoric acid (0.2%, v/v) at a flow-rate of 1.0 mL min⁻¹. All calibration curves reveal good linearity (r² > 0.9998) within the tested concentration ranges. The relative standard deviations for intra-day and inter-day are less than 2.0% and the recoveries range from 98.32% to 103.68% with relative SDs less than 2.0%. This method is successfully applied to quantitate two benzofurans in Radix Eupatorii Chinensis. Therefore, the new HPLC method is proven to be reliable and suitable for the quality control of Radix Eupatorii Chinensis.


Assuntos
Benzofuranos/química , Benzofuranos/isolamento & purificação , Eupatorium/química , Cromatografia Líquida de Alta Pressão , Estrutura Molecular
15.
Artigo em Chinês | MEDLINE | ID: mdl-20476580

RESUMO

OBJECTIVE: To study the effect of chronic rapid eye movement sleep deprivation on energy metabolism, FT3, FT4 in serum. METHODS: Rapid eye movement sleep deprivation of rats were deprived by flower pot, and then the energy metabolism were detected. The FT3, FT4 level in serum was determined by radioimmunoassay kit. RESULTS: Rats after sleep deprivation displayed food intake increased from (75.06 +/- 25.37)g/(d x kg) to (122.30 +/- 20.43)g/(d x kg), body weight substantially decreased from (360.89 +/- 43.01) g to (295.97 +/- 37.95) g, body temperature from (37.62 +/- 1.12) degrees C up to the first (39.00 +/- 0.87) degrees C and then reduced to (37.72 +/- 0.84) degrees C, the basal metabolism rate increased significantly from (1.69 +/- 0.36) mlO2/(g x h) to (2.40 +/- 0.09) mlO2/(g x h), compared with the control group( P < 0.05). Sleep deprivation also resulted significantly lower serum thyroxine levels in comparison with the control, serum free triiodothyronine (FT3) level reduced from (3.38 +/- 0.88) pmol/L to (2.38 +/- 0.83) pmol/L, then free thyroxine(FT4) decreased from (14.62 +/- 3.62) pmol/L to (8.26 +/- 2.80) pmol/L (P < 0.05). CONCLUSION: Rapid eye movement sleep deprivation can change energy metabolism remarkable, as well as the alteration of FT3, FT4 levels in serum.


Assuntos
Metabolismo Energético/fisiologia , Privação do Sono/metabolismo , Sono REM/fisiologia , Tiroxina/sangue , Tri-Iodotironina/análogos & derivados , Animais , Masculino , Ratos , Ratos Wistar , Privação do Sono/sangue , Fatores de Tempo , Tri-Iodotironina/sangue
16.
Yao Xue Xue Bao ; 37(5): 359-61, 2002 May.
Artigo em Chinês | MEDLINE | ID: mdl-12579841

RESUMO

AIM: To establish a RP-HPLC method for determination of cyclovirobuxine D. METHODS: Cyclovirobuxine D reacted with a derivative reagent 1-naphthyl isocyanate in chloroform to form fluorescence derivatives, stopped the reaction by adding the mobile phase and then directly injected the solution into the chromatograph to seperate it by RP-HPLC. The analysis was carried out on C18 column, the mobile phase is methanol-water (85:15), the excitation wavelength was set at 305 nm, emission at wavelength 385 nm, and the flow rate was 1 mL.min-1. The effect of several factors including the reaction medium, temperature, time and amount of 1-naphthyl isocyanate on the yield of the derivatization was also investigated systematically. RESULTS: A simple and rapid RP-HPLC method for the simultaneous isolation and analysis of cyclovirobuxine D and its related substances was developed, and the absence of interference between the derivative peak responses of cyclovirobuxine D and its related substances were verified by UV diode array detecter and MS. The linearity was obtained from 0.75 microgram.mL-1 to 2.5 micrograms.mL-1 of cyclovirobuxine D derivatives with a correlation coefficient of 0.9991. The detection limit of cyclovirobuxine D derivative was 1 ng.mL-1, the repeatability of derivatization was good with relative standard derivation no more than 1.2% and derivative was stable within 48 h. The method described conforms to the validation of China Pharmacopiea compendial methods used for pharmaceutical products in general. CONCLUSION: The established method is proved to be reliable quantitative method for the quality control of cyclovirobuxine D.


Assuntos
Medicamentos de Ervas Chinesas/análise , Buxus/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/isolamento & purificação , Plantas Medicinais/química , Controle de Qualidade
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