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1.
Food Chem ; 366: 130576, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34348222

RESUMO

Cinnamon oil is obtained by steam distillation from cinnamon leaves and is usually considered highly cost-effective compared to bark oil, however, which results in tons of waste cinnamon leaves (WCL) discarded annually. By using MS/MS molecular networking (MN) assisted profiling, six main chemical diversities including flavonols and flavones, phenolic acids, lactones, terpenoids, phenylpropanoids and flavanols were rapid revealed from WCL aqueous extract. 101 compounds were tentatively identified by assigning their MS/MS fragments within typical pathways under ESI-MS/MS dissociation. The featured phenolic acids, terpenoids and their glycosides in cinnamon species were recognized as the main constituents of WCL. The hydrophilic lactones, lignans and flavanols were reported for the first time in cinnamon leaves. Furthermore, ABTS and FRAP assays integrated with MN analysis were conducted to uncover an antioxidant fraction, from which 40 potential antioxidant compounds were rapidly annotated. This fundamental information will help expand the utilization of WCL from cinnamon oil industry.


Assuntos
Antioxidantes , Cinnamomum zeylanicum , Cromatografia Líquida , Extratos Vegetais , Espectrometria de Massas em Tandem
2.
Small ; 17(40): e2102470, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34480417

RESUMO

Tumor cells adapt to excessive oxidative stress by actuating reactive oxygen species (ROS)-defensing system, leading to a resistance to oxidation therapy. In this work, self-delivery photodynamic synergists (designated as PhotoSyn) are developed for oxidative damage amplified tumor therapy. Specifically, PhotoSyn are fabricated by the self-assembly of chlorine e6 (Ce6) and TH588 through π-π stacking and hydrophobic interactions. Without additional carriers, nanoscale PhotoSyn possess an extremely high drug loading rate (up to 100%) and they are found to be fairly stable in aqueous phase with a uniform size distribution. Intravenously injected PhotoSyn prefer to accumulate at tumor sites for effective cellular uptake. More importantly, TH588-mediated MTH1 inhibition could destroy the ROS-defensing system of tumor cells by preventing the elimination of 8-oxo-2'-deoxyguanosine triphosphate (8-oxo-dG), thereby exacerbating the oxidative DNA damage induced by the photodynamic therapy (PDT) of Ce6 under light irradiation. As a consequence, PhotoSyn exhibit enhanced photo toxicity and a significant antitumor effect. This amplified oxidative damage strategy improves the PDT efficiency with a reduced side effect by increasing the lethality of ROS without generating superabundant ROS, which would provide a new insight for developing self-delivery nanoplatforms in photodynamic tumor therapy in clinic.

3.
Biomaterials ; 273: 120854, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33932703

RESUMO

The development of photodynamic therapy (PDT) is severely limited by short half-life of singlet oxygen (1O2) and the hypoxic microenvironment. In this work, a plasma membrane targeted photodynamic O2 economizer (designated as P-POE) is developed to improve the subcellular delivery of photosensitizers and alleviate the tumor hypoxia for enhanced PDT effect. After self-assembly into nanomicelles, P-POE has a relatively high stability and a favorable photochemical performance, which are conducive to boosting the 1O2 production. Besides, the plasma membrane anchoring of P-POE contributes to enhancing the preferential retention and cellular accumulation of photosensitizers on tumor tissues and cells. More importantly, P-POE-induced mitochondrial respiratory depression is demonstrated to reduce the O2 consumption of tumor cells to relieve the hypoxia. Consequently, P-POE still exhibits a robust PDT effect against hypoxic tumors, which greatly inhibits the proliferation of breast cancer with low adverse reactions. This innovative combination of subcellular targeting and hypoxic alleviation would advance the development of individualized drug delivery systems for photodynamic therapy against hypoxic tumors.


Assuntos
Nanopartículas , Fotoquimioterapia , Linhagem Celular Tumoral , Membrana Celular , Humanos , Hipóxia/tratamento farmacológico , Oxigênio , Fármacos Fotossensibilizantes/uso terapêutico
4.
Acta Biomater ; 117: 349-360, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33010514

RESUMO

Development of antitumor agents with high efficiency and low toxicity is one of the most important goals for biomedical research. However, most traditional therapeutic strategies were limited due to their non-specificity and abnormal tumor microenvironments, causing a poor therapeutic efficiency and severe side effects. In this paper, a tumor targeted self-synergistic nanoplatform (designated as PAO@PCN@HA) was developed for chemotherapy sensitized photodynamic therapy (PDT) against hypoxic tumors. The efficient drug loading of phenylarsine oxide (PAO) in porphyrinic metal organic framework of PCN-224 as well as the surface modification of hyaluronic acid (HA) improved the targeted drug delivery and reduced the side effects of PAO at the therapeutic dose. Particularly, PAO as an arsenical-based chemotherapeutic agent could not only induce cell apoptosis by generating reactive oxygen species (ROS), but also regulate tumor microenvironments to improve the PDT effect of PCN-224 by mitigating hypoxia and consuming cellular GSH. Both in vitro and in vivo investigations confirmed an effective self-synergy of PAO@PCN@HA in hypoxic tumor therapy with a low systemic toxicity. This integration of microenvironment adjustment with tumor targeted self-synergistic mechanism might provide a new insight for the development of arsenic-based antitumor strategy for clinical applications.


Assuntos
Antineoplásicos , Arsênio , Neoplasias , Fotoquimioterapia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Arsênio/uso terapêutico , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Humanos , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Microambiente Tumoral
5.
Nat Prod Res ; : 1-7, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31709818

RESUMO

Cysestermerol A (1), a rare and new stilbene sestermer, was isolated from the whole herb of Cynodon dactylon. The planar and relative structures of 1 were elucidated based on HRESIMS, one- and two-dimensional NMR analyses, and its absolute configuration was further established by electronic circular dichroism calculations. Compound 1 obviously increased the glucose consumption in HepG2 cells equivalent to the positive control rosiglitazone and markedly inhibited the activity of α-glucosidase in vitro.

6.
Sci Rep ; 9(1): 15856, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676802

RESUMO

In this paper, modulation of reflected wavefront out of the incident plane by a tunable acoustic metasurface is investigated based on the fully generalized Snell's law in the three-dimensional space. The metasurface is constructed by a square lattice of circular holes with gradient annular bumps. The phase shift is tuned by changing the volume of water filled in the holes. The acoustic wave steering out of the incident plane and the out-of-plane acoustic focusing with the oblique incidence at the subwavelength scale are demonstrated numerically by selecting suitable distributions of water depth. The numerical results show that the wavefront of the reflected wave can be manipulated over a wide frequency range; and the gradient design of the unit cells can suppress the parasitic reflection. The present work is relevant to the practical design of novel acoustic devices.

7.
Ultrasonics ; 65: 154-64, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26518526

RESUMO

In this paper, anti-plane transverse wave propagation in nanoscale periodic layered piezoelectric structures is studied. The localization factor is introduced to characterize the wave propagation behavior. The transfer matrix method based on the nonlocal piezoelectricity continuum theory is used to calculate the localization factor. Additionally, the stiffness matrix method is applied to compute the wave transmission spectra. A cut-off frequency is found, beyond which the elastic waves cannot propagate through the periodic structure. The size effect or the influence of the ratio of the internal to external characteristic lengths on the cut-off frequency and the wave propagation behavior are investigated and discussed.

8.
Zhong Yao Cai ; 30(12): 1502-5, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18422180

RESUMO

OBJECTIVE: To set up method for the quality control of carbonized Cortex Moutan. METHODS: The optimized processing technology of carbonized Cortex Moutan was selected by the time of blood coagulation. Besides, the contents of tannin, adsorbability, paeonol and peoniflorin were researched. RESULTS: To parch the pieces 5 minutes at the temperature of 22 degrees C was the optimized processing technology. CONCLUSION: This study provides a reference to the institution for the quality standard of carbonized Cortex Moutan.


Assuntos
Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Paeonia/química , Tecnologia Farmacêutica/métodos , Acetofenonas/análise , Animais , Benzoatos/análise , Coagulação Sanguínea/efeitos dos fármacos , Hidrocarbonetos Aromáticos com Pontes/análise , Carvão Vegetal , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Glucosídeos/análise , Masculino , Camundongos , Monoterpenos , Casca de Planta/química , Raízes de Plantas/química , Controle de Qualidade , Taninos/análise , Tempo de Coagulação do Sangue Total
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