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1.
Nat Commun ; 12(1): 4993, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404798

RESUMO

Dissipative self-assembly, which requires a continuous supply of fuel to maintain the assembled states far from equilibrium, is the foundation of biological systems. Among a variety of fuels, light, the original fuel of natural dissipative self-assembly, is fundamentally important but remains a challenge to introduce into artificial dissipative self-assemblies. Here, we report an artificial dissipative self-assembly system that is constructed from light-induced amphiphiles. Such dissipative supramolecular assembly is easily performed using protonated sulfonato-merocyanine and chitosan based molecular and macromolecular components in water. Light irradiation induces the assembly of supramolecular nanoparticles, which spontaneously disassemble in the dark due to thermal back relaxation of the molecular switch. Owing to the presence of light-induced amphiphiles and the thermal dissociation mechanism, the lifetimes of these transient supramolecular nanoparticles are highly sensitive to temperature and light power and range from several minutes to hours. By incorporating various fluorophores into transient supramolecular nanoparticles, the processes of aggregation-induced emission and aggregation-caused quenching, along with periodic variations in fluorescent color over time, have been demonstrated. Transient supramolecular assemblies, which act as fluorescence modulators, can also function in human hepatocellular cancer cells.


Assuntos
Corantes Fluorescentes/química , Nanopartículas/química , Água/química , Fluorescência , Células Hep G2 , Humanos , Cinética , Substâncias Macromoleculares , Temperatura
2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(5): 1502-1506, 2018 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-30295275

RESUMO

OBJECTIVE: To explore the immunopathogenesis of Henoch-Schonlein purpara (HSP) by detecting the levels of Th17 cells, IL-17 and matrix metallo proteinase-13 (MMP-13) in peripheral blood and the expression of IL-17 in skin lesions at acate phase of HSP. METHODS: Th17 cell ratio in peripheral blood of HSP group and healthy control group was defected by flow cytometry, the plasma levels of IL-17 and MMP-13 in HSP group and healthy control group were defected by ELISA, and expression level of IL-17 in skin lesion of HSP group and skin tissue of healthy control group was deternined by: immunohistochemistry method. RESULTS: the ratio of Th17 cells in periphral blood of HSP group (1.21±0.59%) was very signif cantly higher than that in peripheral blood of control group (0.71±0.26%) ( t=4.907, P<0.01). The plasma levels of IL-17 and MMP-13 at acute phase of HSP were very significantly higher than those in control group (64.58±36.21) pg/ml vs (26.16±14.90) pg/ml and (17.57±5.40) pg/ml vs (11.53±4.40) pg/ml respectively (t=6.183, P<0.01 and t=5.022, P<0.01). The integrool optical density of IL-17 in skin lesin tissue of HSP group (7.26±2.34) was higher than that in control group (4.61±1.82) ( t=2.877, P<0.01). CONCLUSION: Th17 cells, IL-17 and MMP-13 may be involved in the immunological pathogenesis of HSP.


Assuntos
Púrpura de Schoenlein-Henoch , Células Th17 , Citometria de Fluxo , Humanos , Interleucina-17 , Metaloproteinase 13 da Matriz
3.
ACS Appl Mater Interfaces ; 10(30): 24987-24992, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30010314

RESUMO

A kind of supramolecular assemblies was constructed from two water-soluble and biocompatible saccharides, sulfonato-ß-cyclodextrin (SCD) and chitosan, and characterized by dynamic light scattering (DLS), UV-vis, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results showed that such nanoparticles presented good stability and controlled loading/release property, which enabled them as good drug carrier for berberine chloride (BE), a representative drug from traditional Chinese herbs. That is, the nanoparticles can load BE with high stability in a low-pH environment like that of the stomach but released BE when moved to a high-pH environment like that of the intestine.


Assuntos
Nanopartículas , Berberina , Quitosana , Preparações de Ação Retardada , Portadores de Fármacos , beta-Ciclodextrinas
4.
Food Chem ; 218: 386-395, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27719925

RESUMO

This study aimed to extract and identify anthocyanins from Nitraria tangutorun Bobr. seed meal and establish a green analytical method of anthocyanins. Ultrasound-assisted extraction of anthocyanins from N. tangutorun seed meal was optimized using response surface methodology. Extraction at 70°C for 32.73 min using 51.15% ethanol rendered an extract with 65.04mg/100g of anthocyanins and 947.39mg/100g of polyphenols. An in vitro antioxidant assay showed that the extract exhibited a potent DPPH radical-scavenging capacity. Eight anthocyanins in N. tangutorun seed meal were identified by HPLC-MS, and the main anthocyanin was cyanidin-3-O-(trans-p-coumaroyl)-diglucoside (18.17mg/100g). A green HPLC-DAD method was developed to analyse anthocyanins. A mixtures of ethanol and a 5% (v/v) formic acid aqueous solution at a 20:80 (v/v) ratio was used as the optimized mobile phase. The method was accurate, stable and reliable and could be used to investigate anthocyanins from N. tangutorun seed meal.


Assuntos
Antocianinas/análise , Magnoliopsida/química , Extratos Vegetais/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas , Polifenóis/análise , Sementes/química
5.
Soft Matter ; 11(12): 2488-93, 2015 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-25679755

RESUMO

Biocompatible and enzyme-responsive supramolecular assemblies have attracted more and more interest in biomaterial fields, and find many feasible applications especially in the controlled drug release at specific sites where the target enzyme is located. In this work, novel supramolecular nanoparticles were successfully constructed from two biocompatible materials, i.e. a cyclic polysaccharide named sulfato-ß-cyclodextrin (SCD) and a protein named protamine, through non-covalent association, and fully characterized by means of atomic force microscopy (AFM) and high-resolution transmission electron microscopy (TEM). Significantly, the disassembly of the resulting nanoparticles can respond especially to trypsin over other enzymes. Owing to their trypsin-triggered disassembly behaviors, these nanoparticles can efficiently release the encapsulated model substrate in a controlled manner. That is, the model substrate can be encapsulated inside the nanoparticles with a high stability and released when treated with trypsin.


Assuntos
Materiais Biocompatíveis/síntese química , Enzimas/química , Nanopartículas/química , Polímeros/química , Protaminas/química , beta-Ciclodextrinas/química , Biocatálise , Materiais Biocompatíveis/química
6.
J Pharm Anal ; 1(2): 81-91, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-29403684

RESUMO

In China, traditional Chinese medicines (TCMs) have been used in clinical applications for thousands of years. The successful hyphenation of high-Performance liquid chromatography (HPLC) and mass spectrometry (MS) has been applied widely in TCMs and biological samples analysis. Undoubtedly, HPLC/MS technique has facilitated the understanding of the treatment mechanism of TCMs. We reviewed more than 350 published papers within the last 5 years on HPLC/MS in the analysis of TCMs. The present review focused on the applications of HPLC/MS in the component analysis, metabolites analysis, and pharmacokinetics of TCMs etc. 50% of the literature is related to the component analysis of TCMs, which show that this field is the most populär type of research. In the metabolites analysis, HPLC coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry has been demonstrated to be the powerful tool for the characterization of structural features and fragmentation behavior patterns. This paper presented a brief overview of the applications of HPLC/MS in the analysis of TCMs. HPLC/MS in the fingerprint analysis is reviewed elsewhere.

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