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1.
Nanomaterials (Basel) ; 12(13)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35808117

RESUMO

Benzylation of the electrochemically generated dianion from N-p-tolyl-[60]fullerooxazolidinone with benzyl bromide provides three products with different addition patterns. The product distribution can be dramatically altered by varying the reaction conditions. Based on spectral characterizations, these products have been assigned as mono-benzylated 1,4-adduct and bis-benzylated 1,2,3,16- and 1,4,9,25-adducts, respectively. The assigned 1,2,3,16-adduct has been further established by X-ray diffraction analysis. It is believed that the 1,4-adduct is obtained by decarboxylative benzylation of the dianionic species, while bis-benzylated 1,2,3,16- and 1,4,9,25-adducts are achieved via a rearrangement process. In addition, the electrochemical properties of these products have been studied.

2.
Adv Mater ; 33(8): e2004128, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33432664

RESUMO

Lithium (Li) metal is one of the most promising alternative anode materials of next-generation high-energy-density batteries demanded for advanced energy storage in the coming fourth industrial revolution. Nevertheless, disordered Li deposition easily causes short lifespan and safety concerns and thus severely hinders the practical applications of Li metal batteries. Tremendous efforts are devoted to understanding the mechanism for Li deposition, while the final deposition morphology tightly relies on the Li nucleation and early growth. Here, the recent progress in insightful and influential models proposed to understand the process of Li deposition from nucleation to early growth, including the heterogeneous model, surface diffusion model, crystallography model, space charge model, and Li-SEI model, are highlighted. Inspired by the abovementioned understanding on Li nucleation and early growth, diverse anode-design strategies, which contribute to better batteries with superior electrochemical performance and dendrite-free deposition behavior, are also summarized. This work broadens the horizon for practical Li metal batteries and also sheds light on more understanding of other important metal-based batteries involving the metal deposition process.

3.
J Breast Cancer ; 21(3): 251-258, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30275853

RESUMO

PURPOSE: Multidrug resistance (MDR) remains a major obstacle in the treatment of triple-negative breast cancer (TNBC) with conventional chemotherapeutic agents. A previous study demonstrated that hsa-miRNA-143-3p plays a vital role in drug resistance of TNBC. Downregulation of hsa-miRNA-143-3p upregulated the expression of its target protein cytokine-induced apoptosis inhibitor 1 (CIAPIN1) in order to activate MDR, while upregulation of hsa-miRNA-143-3p effectively enhances the sensitivity of drug-resistant TNBC cells to chemotherapeutics. The present study aimed to further verify these findings in vivo. METHODS: We established a hypodermic tumor nude mice model using paclitaxel-resistant TNBC cells. We expressed ectopic hsa-miRNA-143-3p under the control of a breast cancer-specific human mammaglobin promoter that guided the efficient expression of exogenous hsa-miRNA-143-3p only in breast cancer cells. Thereafter, we overexpressed hsa-miRNA-143-3p in xenografts using a recombinant virus system and quantified the expression of hsa-miRNA-143-3p, CIAPIN1 protein, and proteins encoded by related functional genes by western blot. RESULTS: We successfully completed the prospective exploration of the intravenous virus injection pattern from extensive expression to targeted expression. The overexpression of hsa-miRNA-143-3p significantly alleviated chemoresistance of TNBC by inhibiting viability. In addition, we observed that the expression of CIAPIN1 as a hsa-miRNA-143-3p target protein was remarkably decreased. CONCLUSION: We partly illustrated the mechanism underlying the hsa-miRNA-143-3p/CIAPIN1 drug resistance pathway. HsamiRNA-143-3p as a tumor suppressive microRNA may be a novel target to effectively reverse MDR of TNBC in vivo.

4.
Zhongguo Zhong Yao Za Zhi ; 43(6): 1235-1240, 2018 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-29676134

RESUMO

This study aimed to investigate the colorectal cancer preventive effect of the combined administration of phenolic acids and supercritical extracts from Angelica sinensis. The AOM/DSS model in mice was adopted. Phenolic acids were administrated orally in the initial stage of the model at a dose of 1 g·kg⁻¹ BW, which was combined withtherectal administration with three doses of supercritical extracts (15, 30, 60 g·kg⁻¹ BW). PCNA, 8-oxoguaine, γ-H2AX, iNOS and COX-2 were tested by immunohistochemistry and Western blot assays. The results showed that the combined administration of phenolic acids and supercritical extracts from A. sinensis suppressed the tumor growth and cell proliferation, and DNA damages and inflammatory responses were reduced in a dose-dependent manner. These results indicate that the combined administration of phenolic acids and supercritical extracts from A. sinensis have a certain effect in preventing carcinogenesis.


Assuntos
Angelica sinensis/química , Neoplasias Colorretais/tratamento farmacológico , Hidroxibenzoatos/farmacologia , Extratos Vegetais/farmacologia , Animais , Camundongos
5.
J Zhejiang Univ Sci B ; 15(11): 929-39, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25367786

RESUMO

A rapid, reliable, and sensitive method was developed using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) with an electrospray ionization (ESI) source for determination of seven bioactive compounds in rat plasma after oral administration of Ginkgo biloba tablets (GBTs). The method simultaneously detects bilobalide (BB), ginkgolide A (GA), ginkgolide B (GB), ginkgolide C (GC), quercetin (QCT), kaempferol (KMF), and isorhamnetin (ISR) for pharmacokinetic study. The analytes and internal standard (IS) were extracted from rat plasma by acetidin. An MS/MS detection was conducted using multiple reaction monitoring (MRM) and operating in the negative ionization mode. The calibration curve ranges were 5-500, 5-500, 2.5-250, 1-100, 1-100, 1-100, and 1-100 ng/ml for BB, GA, GB, GC, QCT, KMF, and ISR, respectively. The mean recovery of the analytes ranged from 68.11% to 84.42%. The intra- and inter-day precisions were in the range of 2.33%-9.86% and the accuracies were between 87.67% and 108.37%. The method was used successfully in a pharmacokinetic study of GBTs. The pharmacokinetic parameters of seven compounds were analyzed using a non-compartment model. Plasma concentrations of the seven compounds were determined up to 48 h after administration, and their pharmacokinetic parameters were in agreement with previous studies.


Assuntos
Cromatografia Líquida/métodos , Flavonóis/sangue , Ginkgo biloba/química , Lactonas/sangue , Extratos Vegetais/farmacocinética , Espectrometria de Massas por Ionização por Electrospray/métodos , Administração Oral , Animais , Relação Dose-Resposta a Droga , Masculino , Extratos Vegetais/administração & dosagem , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Comprimidos , Terpenos/sangue
6.
Zhongguo Zhong Yao Za Zhi ; 39(7): 1265-9, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-25011266

RESUMO

To study the chemo-preventive effect of the supercritical extracts from Angelica sinensis (SFE-AS) on induced colorectal carcinoma in mice by using the AOM/DSS-induced male mice colorectal carcinoma model, and discuss its possible action mechanism. Male Balb/c mice were subcutaneously injected with single dose of azoxymethane (AOM, 10 mg x kg(-1) body weight). One week later, they were given 2% dextran sodium sulfate (DSS) in drinking water for 7 days to induce colorectal carcinoma. Each drug group was orally administered with supercritical extracts from Angelica sinensis at 15, 30, 60 mg x kg(-1) until the 17th week. The tumor incidence rate of the SFE-AS group, mice tumor-bearing quantity and tumor-bearing volume of the SFE-AS group were lower than that of the AOM/DSS model control group, which may be related with the significant reduction of PCNA, COX-2, iNOS in the AOM/DSS-induced mouse colorectal carcinoma model associated with inflammation by SFE-AS. According to the results of this study, SFE-AS showed an intervention effect in the incidence and development of AOM/DSS-induced mouse colorectal carcinoma associated with inflammation, and could be further used in chemo-preventive studies on human colorectal carcinoma.


Assuntos
Angelica sinensis/química , Neoplasias do Colo/prevenção & controle , Neoplasias Colorretais/prevenção & controle , Medicamentos de Ervas Chinesas/administração & dosagem , Animais , Azoximetano/efeitos adversos , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/genética , Neoplasias do Colo/imunologia , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/imunologia
7.
Zhongguo Zhong Yao Za Zhi ; 39(2): 222-9, 2014 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-24761635

RESUMO

To prepare Zhitong micro-emulsion in this study, with the empirical formula of Zhitong preparation as the model medicine, the essential oil in the formula as the oil phase, and the water decoction as the water phase. The types of surfactant and co-surfactant were investigated. The changes in micro-emulsion conductivity and construction, the water percentage in the micro-emulsion system, the changing curve of conductivity and the fine pseudo-ternary phase diagram of micro-emulsion were drawn to determine the surfactant-co-surfactant mass ratio (K(m)). Subsequently, the D-mixture design was used to optimize Zhitong Micro-emulsion formula, with particle size and surface tension of micro-emulsion as the indexes. Finally, efforts were made to determine part of physical parameters of Zhitong micro-emulsion and preliminarily detect its stability. The results showed that the micro-emulsion was optimal with the EL-35-tween 20 ratio of 4:1 in surfactant, whereas the absolute ethyl alcohol was recommended as the co-surfactant. The ratio between surfactant and co-surfactant (K(m)) was 1.5. The finalized micro-emulsion formula contains 12% surfactant, 8% co-surfactant, 70% 1 g x mL(-1) water decoction and 8% oil. The results of the preliminary stability experiment showed a better stability of Zhitong micro-emulsion.


Assuntos
Química Farmacêutica/métodos , Medicamentos de Ervas Chinesas/química , Emulsões , Tensoativos/química , Temperatura
8.
J Zhejiang Univ Sci B ; 15(2): 153-64, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24510708

RESUMO

The aim of this present study is to investigate the effect of Zanthoxylum bungeanum oil (essential oil from Z. bungeanum Maxim.) on cytotoxicity and the transdermal permeation of 5-fluorouracil and indomethacin. The cytotoxicity of Z. bungeanum oil on dermal fibroblasts and epidermal keratinocytes was studied using an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The rat skin was employed to determine the percutaneous penetration enhancement effect of Z. bungeanum oil on hydrophilic and lipophilic model drugs, i.e., 5-fluorouracil and indomethacin. The secondary structure changes of the rat stratum corneum (SC) were determined using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and saturated solubilities and SC/vehicle partition coefficients of two model drugs with and without Z. bungeanum oil were also measured to understand its related mechanisms of action. It was found that the half maximal inhibitory concentration (IC50) values of Z. bungeanum oil were significantly lower in HaCaT and CCC-ESF-1 cell lines compared to the well-established and standard penetration enhancer Azone. The Z. bungeanum oil at various concentrations effectively facilitated the percutaneous penetration of two model drugs across the rat skin. In addition, the mechanisms of permeation enhancement by Z. bungeanum oil could be explained with saturated solubility, SC/vehicle partition coefficient, and secondary structure changes of SC.


Assuntos
Fibroblastos/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Óleos Voláteis/química , Óleos de Plantas/química , Pele/efeitos dos fármacos , Zanthoxylum/química , Administração Cutânea , Animais , Linhagem Celular , Linhagem Celular Tumoral , Fluoruracila/administração & dosagem , Humanos , Indometacina/administração & dosagem , Concentração Inibidora 50 , Masculino , Ratos , Ratos Sprague-Dawley , Pele/metabolismo , Absorção Cutânea , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Sais de Tetrazólio , Tiazóis
9.
Zhongguo Zhong Yao Za Zhi ; 38(14): 2292-6, 2013 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-24199557

RESUMO

Using sustained release tablets of Ginkgo bibolia extract as model drug,discuss technical feasibility of using biotic index to evaluate sustained release tablets. Chosing two pharmacological indicatrix: antioxidant ability and inhibition of platelet aggregation, to investigate the influence factors on experimental result, optimize the method and experiment condition, and set up pharmacological indicatrix evaluation method. Using those methods to determinate biological effects of dissolved liquid. Drawing release curves and biological effects curves, discussing their correlation. A good correlation was observed, illustrating that pharmacological indicatrix could evaluate sustained release tablets.


Assuntos
Ginkgo biloba/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Preparações de Ação Retardada , Feminino , Masculino , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/química , Coelhos , Comprimidos
10.
Zhongguo Zhong Yao Za Zhi ; 38(16): 2597-600, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24228570

RESUMO

The present paper was designed to investigate the effect of varying concentrations of ethanol in receiver solution on the in vitro transdermal permeation of drug across the rat skin. 5-fluorouracil (5-FU) was used as the model drug on account of its good hydrophility, the excised rat skins were treated with different concentration ethanol prepared with normal saline for 12 h, then replaced by normal saline and added the saturated model drug into the donor compartment to determine the transdermal parameters of the drug. Meanwhile, scanning electron microscopy (SEM) was employed to monitor the effect of the different concentration ethanol on the stratum corneum of the rat skin. The ethanol below the concentration of 15% didn't significantly affect the barrier profile of the rat skin, while significant difference of in steady-state transdermal rate and lag times were observed when the concentration of ethanol was 20% or above. The SEM studies indicated that wrinkle of the intact rat skin gradually disappeared and a number of flakes were desquamated from the skin when the concentration of ethanol was above 20%. The results showed that the low concentration of the ethanol (below 15%) didn't obviously affect the excised skin, yet the barrier profile of rat skin would significantly disrupted with the concentration of ethanol above 20%.


Assuntos
Química Farmacêutica/métodos , Etanol/química , Pele/metabolismo , Animais , Fluoruracila/química , Fluoruracila/metabolismo , Masculino , Microscopia Eletroquímica de Varredura , Permeabilidade , Ratos , Ratos Sprague-Dawley , Pele/ultraestrutura
11.
Zhongguo Zhong Yao Za Zhi ; 38(16): 2614-7, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24228574

RESUMO

To study the varieties of adhesives in gels on the basis of previous studies, dosage of adhesives required for forming of gels by using the single factor design, as well as the drug loading capacity of gels with the adhesiveness and stickiness as the scoring indicators, in order to determine the forming method of analgesic micro-emulsion gel. Subsequently, the improved Franz diffusing cell method was adopted to study the release of water-soluble components and liposoluble components in analgesic gels, with imperatorin and ferulic acid as index components. The results showed that analgesic micro-emulsion gel could promote the release of imperatorin and ferulic acid. Finally, HPLC was used to detect that the loss amount of volatile components in analgesic micro-emulsion gel was 23.13% lower than that in the original analgesic gel. In the experiment, we finally prepared finished products of micro-emulsion gel, discovered that the micro-emulsion technology is helpful to improve the synchronous release of water-soluble components and liposoluble components in prescriptions and can reduce the loss of volatile components.


Assuntos
Analgésicos/química , Química Farmacêutica/métodos , Medicamentos de Ervas Chinesas/química , Dor/tratamento farmacológico , Adesividade , Analgésicos/uso terapêutico , Animais , Medicamentos de Ervas Chinesas/uso terapêutico , Emulsões , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Pomadas
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