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1.
Opt Express ; 32(9): 16140-16155, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859250

RESUMO

In this paper, high-order LP modes based Sagnac interference for temperature sensing are proposed and investigated theoretically. Based on the specific high-order LP modes excited through the mode selective couplers (MSCs), we design a stress-induced Panda-type few-mode fiber (FMF) supporting 4 LP modes and construct a Sagnac interferometer to achieve a highly sensitive temperature sensor. The performances of different LP modes (LP01, LP11, LP21, and LP02) are explored under a single Sagnac interferometer and paralleled Sagnac interferometers, respectively. LP21 mode has the highest temperature sensitivity. Compared with fundamental mode (LP01), the temperature sensitivity based on LP21 mode improved by 18.2% at least. In addition, a way to achieve the enhanced optical Vernier effect is proposed. It should be noted that two Sagnac loops are located in two temperature boxes of opposite variation trends, respectively. Both two Sagnac interferometers act as the sensing element, which is different from the traditional optical Vernier effect. The temperature sensitivity of novel enhanced optical Vernier effect is magnified by 8 times, which is larger than 5 times the traditional Vernier effect. The novel approach avoids measurement errors and improves the stability of the sensing system. The focus of this research is on high-order mode interference, which has important guiding significance for the development of highly sensitive Sagnac sensors.

2.
Langmuir ; 39(22): 7660-7671, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37219917

RESUMO

The resistance of cancer cells to anticancer drugs has been recognized as one of the main reasons for chemotherapy failure. Multidrug combination therapy is one of the most effective ways to solve this problem. Therefore, in this article, we designed and synthesized a pH/GSH dual-responsive camptothecin/doxorubicin (CPT/DOX) dual pro-drug synergistic treatment system with the aim of overcoming the resistance of non-small cell lung cancer A549/ADR cells to DOX. The pro-drug cRGD-PEOz-S-S-CPT (cPzT) was obtained by linking CPT to poly(2-ethyl-2-oxazoline) (PEOz) with endosomal escape properties through a GSH-responsive disulfide bond and modifying it with the targeted peptide cRGD. The pro-drug mPEG-NH-N=C-DOX (mPX) was synthesized by attaching DOX to polyethylene glycol (PEG) through acid-sensitive hydrazone bonds. The dual pro-drug micelles cPzT/mPX configured according to the CPT/DOX mass ratio of 3:1 showed a strong synergistic therapeutic effect at IC50 with a combined therapy index CI = 0.49, far less than 1. Moreover, with the further improvement of the inhibition rate, the 3:1 ratio showed a stronger synergistic therapeutic effect than other ratios. The cPzT/mPX micelles not only had better targeted uptake ability but also showed a better therapeutic effect in both 2D and 3D tumor suppression assays relative to free CPT/DOX and significantly enhanced the penetration ability into solid tumors. In addition, the results of confocal laser scanning microscopy (CLSM) showed that cPzT/mPX could effectively overcome the resistance of A549/ADR cells to DOX by delivering DOX into the nucleus to exert its effect. Thus, this dual pro-drug synergistic therapy system combining targeting and endosomal escape ability provides a possible strategy to overcome tumor drug resistance.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Pró-Fármacos , Humanos , Micelas , Pró-Fármacos/química , Doxorrubicina , Polietilenoglicóis/química , Camptotecina/farmacologia , Camptotecina/química , Endossomos , Concentração de Íons de Hidrogênio , Células MCF-7
3.
Phys Chem Chem Phys ; 24(14): 8415-8421, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35343544

RESUMO

The structures, stabilities and superconducting properties of LiSeHn (n = 4-10) hydrides at 150-300 GPa were studied by the genetic algorithm (GA) and DFT calculation method. Three stable stoichiometries of LiSeH4, LiSeH6 and LiSeH10 were uncovered under high pressure. Four other metastable stoichiometries of LiSeH5, LiSeH7, LiSeH8, and LiSeH9 were also studied. By analyzing the electronic band structure and electronic density of states, C2 LiSeH4, Pmm2 LiSeH6 and C2 LiSeH10 were all found to be metal phases above 150 GPa. Electron-phonon coupling calculations showed that C2 LiSeH4 and Pmm2 LiSeH6 were promising superconductors. The predicted Tc values of C2 LiSeH4 and Pmm2 LiSeH6 were 77 K at 200 GPa and 111 K at 250 GPa, respectively.

4.
Environ Res ; 204(Pt B): 112077, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34560060

RESUMO

The negative consequences, such as healthy and environmental issues, brought by rapid urbanization and interactive human activities result in increasing social uncertainties, unreliable predictions, and poor management decisions. For instance, the Coronavirus Disease (COVID-19) occurred in 2019 has been plaguing many countries. Aiming at controlling the spread of COVID-19, countries around the world have adopted various mitigation and suppression strategies. However, how to comprehensively eva luate different mitigation strategies remains unexplored. To this end, based on the Artificial societies, Computational experiments, Parallel execution (ACP) approach, we proposed a system model, which clarifies the process to collect the necessary data and conduct large-scale computational experiments to evaluate the effectiveness of different mitigation strategies. Specifically, we established an artificial society of Wuhan city through geo-environment modeling, population modeling, contact behavior modeling, disease spread modeling and mitigation strategy modeling. Moreover, we established an evaluation model in terms of the control effects and economic costs of the mitigation strategy. With respect to the control effects, it is directly reflected by indicators such as the cumulative number of diseases and deaths, while the relationship between mitigation strategies and economic costs is built based on the CO2 emission. Finally, large-scale simulation experiments are conducted to evaluate the mitigation strategies of six countries. The results reveal that the more strict mitigation strategies achieve better control effects and less economic costs.


Assuntos
COVID-19 , Dióxido de Carbono , Simulação por Computador , Humanos , SARS-CoV-2
5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(6): 499-502, 2020 Dec 08.
Artigo em Zh | MEDLINE | ID: mdl-33314857

RESUMO

A kind of adjustable external fixation device for lower extremity is designed. The circuit is mainly composed of TEC1-00703 semiconductor refrigeration chip, HZC-30A pressure sensor, STC89C52RC single chip microcomputer and other electrical components. It can realize the timing intelligent temperature control and meet the local fixed-point refrigeration. The design of adjustable structure and the application of intelligent air cushion can satisfy the full fixation of lower limbs of different individuals. Its operation does not need much medical knowledge. It can solve the problem of emergency transportation and follow-up treatment of lower limb injury in ice and snow sports. It has a good application prospect and universality.


Assuntos
Fixadores Externos , Extremidade Inferior , Refrigeração , Semicondutores , Fixação de Fratura , Humanos
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(8): 2399-2404, 2016 Aug.
Artigo em Zh | MEDLINE | ID: mdl-30073824

RESUMO

Cerium doped Y2SiO5 (YSO) is an important scintillator material due to its high density, non-hygroscopic, excellent light output and fast decay time nature. in the paper, Y2SiO5∶Ce3+0.2%(YSO∶Ce) was grown with high-temperature solid-phase method. The time-resolved excitation and emission spectra and fluorescent decay curves at low temperature and room temperature (RT) were measured and discussed. There were two types of luminescence, one was the crystal defect emission, the center at 320 nm; the other one was doped Ce3+ ions 5d→4f emission, the center at 440 nm. Only when the excitation energy (Ex) was greater than the band gap width (Eg), the crystal defect emission can be observed corresponding to slow process, and the emission intensity was higher at low temperature. The crystals defect emission was hardly observed in the time-resolved emission spectra when the temperature rose to room temperature because of temperature quenching. Regions from 60~300 nm corresponding to emission due to 5d→4f transitions in the activator Ce3+ ions peaks at 440 nm, a plurality of excitation peaks were observed. Among them, the excitation with energy less than 6.1 eV(Ex

7.
Sci Rep ; 14(1): 7091, 2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38528032

RESUMO

Graphene quantum dots (GQDs) have attracted significant attention in biomedicine, while extensive investigations have revealed a reverse regarding the potential biotoxicity of GQDs. In order to supplementing the understanding of the toxicity profile of GQDs, this study employs a molecular dynamics (MD) simulation approach to systematically investigate the potential toxicity of both GQDs and Graphene Oxide Quantum Dots (GOQDs) on the Anterior Gradient Homolog 2 (AGR2) protein, a key protein capable of protecting the intestine. We construct two typical simulation systems, in which an AGR2 protein is encircled by either GQDs or GOQDs. The MD results demonstrate that both GQDs and GOQDs can directly make contact with and even cover the active site (specifically, the Cys81 amino acid) of the AGR2 protein. This suggests that GQDs and GOQDs have the capability to inhibit or interfere with the normal biological interaction of the AGR2 active site with its target protein. Thus, GQDs and GOQDs exhibit potential detrimental effects on the AGR2 protein. Detailed analyses reveal that GQDs adhere to the Cys81 residue due to van der Waals (vdW) interaction forces, whereas GOQDs attach to the Cys81 residue through a combination of vdW (primary) and Coulomb (secondary) interactions. Furthermore, GQDs aggregation typically adsorb onto the AGR2 active site, while GOQDs adsorb to the active site of AGR2 one by one. Consequently, these findings shed new light on the potential adverse impact of GQDs and GOQDs on the AGR2 protein via directly covering the active site of AGR2, providing valuable molecular insights for the toxicity profile of GQD nanomaterials.


Assuntos
Grafite , Mucoproteínas , Pontos Quânticos , Domínio Catalítico , Grafite/toxicidade , Grafite/química , Simulação de Dinâmica Molecular , Óxidos , Pontos Quânticos/toxicidade , Pontos Quânticos/química , Mucoproteínas/metabolismo , Proteínas Oncogênicas/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-38756075

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is a highly heterogeneous brain tumor with limited treatment options and a poor prognosis. Cancer stem cells (CSCs) have emerged as a critical factor in GBM resistance and management, contributing to tumor growth, heterogeneity, and immunosuppression. The transcription factor FOXM1 has been identified as a key player in the progression, spread, and therapy resistance of various cancers, including GBM. OBJECTIVE: In this research, the objective was to perform structure-based in silico screening with the aim of identifying natural compounds proficient in targeting the DNA-binding domain (DBD) of the FOXM1 protein. METHODS: In this study, in silico tools were employed for screening a hundred naturally occurring compounds capable of targeting the FOXM1 protein. Through molecular docking analysis and pharmacokinetic profiling, five compounds were found to be promising candidates for extensive interaction with the FOXM1 protein. Further, these compounds were validated for the stability of the FOXM1-natural compound complex using molecular dynamics (MD) simulations. RESULTS: Four compounds, such as Withaferin A, Bryophyllin A, Silybin B, Sanguinarine and Troglitazone (control compound), emerged as promising candidates with substantial interactions with FOXM1, suggesting their potential as a protein inhibitor based on molecular docking investigations. After MD simulation analysis, the FOXM1- Bryophyllin A complex was found to maintain the highest stability, and the other three ligands had moderate but comparable binding affinities over a period of 100 ns. CONCLUSION: This study provides valuable insights into four promising FOXM1 inhibitors that have the ability to induce senescence in GBM stem cells. These findings contribute to the development of structure-based designing strategies for FOXM1 inhibitors and innovative therapeutic approaches for the treatment of Glioblastoma.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(12): 3415-8, 2013 Dec.
Artigo em Zh | MEDLINE | ID: mdl-24611414

RESUMO

The authors studied the nonlocalized interference in multiple-beam interferometer. The light intensity distribution function was obtained. The result shows that the function in the circle center has the same form with localized interference. Numerical simulation method was used to analyse the light intensity distribution function. As the reflection coefficient increases, the stripe becomes sharp, Resolution ratio was improved, while the noise occured around the lower interference index. The noise becomes obviously as the reflection coefficient increases. While changing the receiving screen distance, the simulation result shows that linear relationship exists between inteference index and cosine value of interference stripe dip angle. The mirror spacing can be obtained through the straight line slope. With changing the mirror spacing, the numerical simulation result shows that linear relationship exists between interference index and stripe radii square. The straight slope shows a linear relationship with the mirror spacing.

10.
Materials (Basel) ; 16(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37687496

RESUMO

In this paper, a dual-core photonic crystal fiber (DC-PCF) sensitivity sensor filled with magnetic liquid is introduced and investigated with the finite element method (FEM). To regulate the energy coupling involving the two cores, the magnetic fluid is filled into the pore between the two cores. To adjust the coupling between the supermodes in the DC-PCF, the refractive index (RI) of the air hole filled magnetic fluid may change due to the external magnetic field. This specifically created a magnetic fluid-filled DC-PCF; the magnetic fluid-filled hole is not used as the core for energy transmission, thus avoiding transmission loss. The dip wavelength and the magnetic field displayed an excellent linear connection between 80 and 260 Oe, depending on the numerical data. The detection sensitivity of the magnetic field reached 515.75 pm/Oe at a short fiber length of 482 µm. The designed magnetic fluid-filled DC-PCF has high sensitivity and small volume and has great application prospects in magnetic field detection in the medical and industrial fields.

11.
Pharmazie ; 67(5): 426-31, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22764577

RESUMO

The transfection agent polycation polyethylenimine (PEI) has been rarely used to construct liposomes for chemical antitumor drugs. In this study, it was introduced into cisplatin (CDDP) encapsulated neutral liposomes (CDDP-NL) by amphiphilic PEI-cholesterol (PEI-Chol) to investigate its effect on the antitumor activity in A549 cells. The IC50 was 0.65 +/- 0.02, 2.94 +/- 0.21 and 2.03 +/- 0.15 microg/ml for CDDP-cationic liposomes (CDDP-CL), CDDP-NL and free CDDP, respectively. The enhanced anticancer activity was attributed to the addition of PEI-Chol which influenced cellular processing of CDDP. With the help of inhibitors, we found that besides clathrin dependent and actin dependent uptake pathways, caveolae-mediated endocytosis was involved in the internalization of CDDP-CL. Improved internalization of CDDP was observed. Intracellular Pt accumulations were 6.5 times and 3 times of those in CDDP-NL and free CDDP groups, respectively. The differences of intracellular location caused by endocytosis routes and lysosomes escape capacity of PEL-Chol was observed by fluorescence colocalization studies. PEI-Chol also decreased the Pt fraction exported out of cells and extended the cellular Pt retention of CDDP liposomes. In conclusion, cationic modification of liposomes with PEI is a potential and promising way for antitumor drug delivery.


Assuntos
Antineoplásicos/administração & dosagem , Portadores de Fármacos/química , Lipossomos/química , Polietilenoimina/química , Análise de Variância , Antineoplásicos/química , Antineoplásicos/farmacologia , Cátions/química , Linhagem Celular Tumoral , Sobrevivência Celular , Cisplatino/administração & dosagem , Sistemas de Liberação de Medicamentos , Endocitose/efeitos dos fármacos , Humanos , Tamanho da Partícula , Platina/química , Platina/metabolismo
12.
ACS Appl Mater Interfaces ; 14(18): 20616-20627, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35471860

RESUMO

Nanochemotherapy is recognized as one of the most promising cancer treatment options, and the design of the carrier has a crucial impact on the final efficacy. To precisely improve the efficacy and reduce the toxicity, we combined the clinical contrast agent (Gd-DTPA) with a stimulus-sensitive o-nitrobenzyl ester and then prepared a series of nNBGD lipids by varying the carbon chain length of the hydrophobic group. The self-assembled nNBGD liposomes can be tracked by MRI to localize the aggregation of drug carriers in vivo, so as to prompt the application of light stimulation at the optimal time to facilitate the precise release of carriers at the lesion site. And the application potential of this strategy was verified with 88% tumor suppression effect in the 12NBGD-DOX+UV group. In addition, this paper emphasizes that small differences in structure can affect the overall performance of the carriers. By exploration of the differences in stability, drug loading, stimulus responsiveness, MRI imaging effect, and toxicity of the series of nNBGD carriers, the relationship between the length of the hydrophobic group of nNBGD lipids and the overall performance of the carriers is given, which provides experimental support and design reference for other carriers.


Assuntos
Doxorrubicina , Neoplasias , Meios de Contraste/química , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Lipídeos , Lipossomos/química , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Sistemas de Liberação de Fármacos por Nanopartículas , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
13.
J Phys Condens Matter ; 34(35)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35714608

RESUMO

The calcium hydrides and lanthanum hydrides under high pressures have been reported to have good superconducting properties with high-TC. In this work, the structures and superconductivities of Ca-La-H ternary hydrides have been studied by genetic algorithm and density functional theory calculations. Our results show that at the pressure range of 100-300 GPa, the most stable structure of CaLaH12has aCmmmsymmetry, in which there is a H24hydrogen cage. It can be expected to have high possibility to be synthesized due to its large stability. Furthermore, the predictedTCof theCmmm-CaLaH12structure is about 140 K at 150 GPa, and when the pressure decreases to 30 GPa, the CaLaH12structure with aC2/msymmetry has a predictedTCof about 49 K. The CaLaH12is suggested to be a stable good superconductor with large stability and performs well at relatively low pressures.

14.
Biomater Adv ; 134: 112558, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35525754

RESUMO

Cancer treatment is imminent, and controlled drug carriers are an important development direction for future clinical chemotherapy. Visual guidance is a feasible means to achieve precise treatment, reduce toxicity and increase drug efficacy. However, the existing visual control methods are limited by imaging time-consuming, sensitivity and side effects. In addition, the ability of the carrier to respond to environmental stimuli in vivo is another difficulty that limits its application. Here, we propose a highly stimulus-responsive GC liposome with precise tracing and sensitive feedback capabilities. It combines magnetic resonance imaging and fluorescence imaging, and addresses the need for precise visualization by alternating imaging modalities. More importantly, GC liposomes are a carrier that can accumulate stimuli. In this paper, by tracking the fragmentation process of empty GC and drug-loaded D-GC liposomes, we confirm the synergistic effect between multiple stimuli, which can result in a more efficient drug release performance. Finally, in mice models we examined the GC liposome imaging approach and the D-GC + UV group guided by this visualization exhibited the highest tumor inhibition efficiency (6.85-fold). This study highlights the advantages of alternate visualization-guided and co-stimulation treatment strategies, and provides design ideas and potential materials for efficient and less toxic cancer treatments.


Assuntos
Lipossomos , Neoplasias , Animais , Portadores de Fármacos , Liberação Controlada de Fármacos , Imageamento por Ressonância Magnética/métodos , Camundongos
15.
Acta Biomater ; 141: 374-387, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-34971788

RESUMO

Controlled-release drug carriers in cancer therapy are the most ideal way to reduce toxicity and improve drug efficacy. Since light stimulation is precise and operable, most multi-stimulation response carriers utilize phototherapy to enhance release efficiency. However, phototoxicity severely limits the application of phototherapy. Herein, we designed and synthesized a Cou-ONB lipid with sensitive fluorescence feedback and multi-stimulus response. COBL liposomes prepared from Cou-ONB lipids will passively aggregate at the tumor and guide phototherapy by fluorescence. More importantly, it can reflect the drug release effect in vivo through its own sensitive fluorescence changes, further enabling precise phototherapy and reducing phototoxicity. In this paper, the multi-stimulus superimposed response and precise fluorescence-guided performance of COBL liposomes were investigated at the molecular, liposome, cellular, and animal levels. Finally, tumor treatment experiments showed that the d-COBL-UV group had the best tumor suppression effect (5.3-fold). This paper highlights a real-time fluorescence-guided multi-stimulus superposition strategy and provides a design idea to precisely implement exogenous stimuli by displaying the degree of drug release, aiming to achieve less toxic and more efficient cancer therapy through timely and precise multi-stimulation. STATEMENT OF SIGNIFICANCE: Multi-stimulus responsive drug carriers have been extensively developed in the last decade. Visual guidance is an important tool to achieve precision medicine and precise control of drug release. However, the available visualization materials are more aimed at directing stimulation at the optimal moment. There is little discussion on when to stop exogenous stimulation and how to minimize the damage of stimulation to the patient. Here, we provide a Cou-ONB lipid that not only responds to multiple stimuli, but also provides sensitive feedback on its own dissociation with a fluorescent signal so that physicians can adjust exogenous stimuli in a timely manner. This paper provides insights to facilitate precision drug delivery systems, providing viable design ideas for precise, efficient, and less toxic cancer therapies.


Assuntos
Lipossomos , Neoplasias , Animais , Sistemas de Liberação de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Lipídeos/uso terapêutico , Lipossomos/química , Neoplasias/patologia
16.
Front Genet ; 13: 941098, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36246605

RESUMO

Osteoporosis is a serious threat to human life. Guben Zenggu Granule is an empirical prescription for clinical treatment of osteoporosis. MC3T3-E1 cells are mouse osteogenic precursor cells with osteogenic differentiation, and are classic cells for studying bone metabolism and osteogenic mechanism, as well as mechanical stimulation sensitive cells. Therefore, it can be inferred that Guben Zenggu granule can repair MC3T3-E1 cells under continuous static pressure overload. This study aims to through the network of pharmacology and gene sequencing method, reveal thrift increase bone particles under the condition of continuous static pressure overload on osteogenesis mechanism of MC3T3-E1 cells. In the process of analysis, from a variety of 98 compounds was predicted in the database, a collection of 474 goals, a total of 29,164 difference between two groups of genes. Then, construction of composite targets between cells and predict targets and protein - protein interaction networks, and through the cluster analysis to further explore the relationship between the target. In addition, linkages between target proteins and cells were further identified using Gene Ontology (GO) and Pathways (KEGG Pathway). Finally, the repair effect of Guben Zenggu granule on MC3T3-E1 cells under continuous static pressure overload was verified through experiments, so as to accurately explain the pharmacodynamic mechanism of Traditional Chinese medicine.

17.
Innovation (Camb) ; 3(5): 100274, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-35832746

RESUMO

Strategy evaluation and optimization in response to troubling urban issues has become a challenging issue due to increasing social uncertainty, unreliable predictions, and poor decision-making. To address this problem, we propose a universal computational experiment framework with a fine-grained artificial society that is integrated with data-based models. The purpose of the framework is to evaluate the consequences of various combinations of strategies geared towards reaching a Pareto optimum with regards to efficacy versus costs. As an example, by modeling coronavirus 2019 mitigation, we show that Pareto frontier nations could achieve better economic growth and more effective epidemic control through the analysis of real-world data. Our work suggests that a nation's intervention strategy could be optimized based on the measures adopted by Pareto frontier nations through large-scale computational experiments. Our solution has been validated for epidemic control, and it can be generalized to other urban issues as well.

18.
Colloids Surf B Biointerfaces ; 205: 111866, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34044333

RESUMO

Constructing highly efficient and multifunctional nanoparticles to overcome the multiple challenges of targeted drug delivery is a new strategy urgently needed in tumor therapy. Here, we synthesized pH-responsive prodrug (PEG2K-NH-N-DOX), GSH-responsive prodrug (PEG2K-S-S-CPT), folate-receptor targeting polymers (FA-PEG2K-L8, FA-PEG2K-TOS) and T1-enhanced magnetic resonance imaging contrast agents (Gd-DTPA-N16-16), used to encapsulate combrestatinA4 (CA4) to prepare multifunctional nanoparticles (FTDCAG NPs). Unlike other nanoparticles, FTDCAG NPs contains three drugs with the ability to control the release in time and space, which can maximize the effectiveness of precise cancer chemotherapy. We first confirmed that specific binding between FTDCAG NPs and overexpressed folate-receptor cells by flow cytometry and confocal laser scanning microscopy. We then investigated the spatiotemporally controlled release ability of FTDCAG NPs loaded with doxorubicin (DOX), CA4 and camptothecin (CPT). Relative to pH = 7.4, the release efficiency of CA4 in the pH = 6.5 increased by 63.4 %. The first released CA4 is able to destroy the angiogenesis and help tumor cells to be exposed to the remaining FTDCG NPs. After being internalized into the tumor cells, FTDCG NPs is disassembled and the CPT and DOX were released due to the increase of intracellular GSH concentration and the decrease of pH value. Besides, the relaxation time of FTDCAG NPs is 3.86 times that of clinical Gd-DTPA, and the in vitro and vivo T1-weighted imaging is brighter, which can be used to trace the nanoparticles by MRI. Therefore, FTDCAG NPs provide an efficient strategy for the design of multifunctional drug delivery systems for enhancing antitumor efficacy.


Assuntos
Nanopartículas , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Polímeros
19.
Biomater Sci ; 9(14): 4968-4983, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34085682

RESUMO

Reactive oxygen species (ROS) are not only used as a therapeutic reagent in chemodynamic therapy (CDT), to stimulate the release of antineoplastic drugs, they can also be used to achieve a combined effect of CDT and chemotherapy to enhance anticancer effects. Herein, we synthesized a pH-responsive prodrug (PEG2k-NH-N-DOX), ROS-responsive prodrug (PEG2k-S-S-CPT-ROS), organic CDT agents (TPP-PEG2k-LND, TPP-PEG2k-TOS), and T1-enhanced magnetic resonance imaging contrast agents (Gd-DTPA-N16-16), and used them to encapsulate combrestatinA4 (CA4) to prepare traceable pH/ROS dual-responsive multifunctional nanoparticles (TLDCAG NPs) with endogenous ROS burst and spatiotemporally controlled multiple drug release ability. Firstly, TLDCAG NPs were accumulated in the tumor cell microenvironment via an enhanced permeability and retention (EPR) effect. Secondly, CA4 was released and specifically destroyed angiogenesis to facilitate the interaction between the tumor and the remaining TLDCG NPs. After accumulating in tumor cells, the TLDCG NPs could be destroyed under acidic conditions to quickly release doxorubicin (DOX), TPP-PEG2k-LND, and TPP-PEG2k-TOS. Thirdly, TPP-PEG2k-LND and TPP-PEG2k-TOS quickly targeted mitochondria, induced endogenous ROS bursts, reduced the mitochondrial membrane potential, and induced tumor cell apoptosis. Endogenous ROS can not only be used as a therapeutic reagent for CDT, but also can cut off the thioketal bond in PEG2k-S-S-CPT-ROS and release camptothecin (CPT). Finally, TLDCAG NPs were traced by magnetic resonance imaging (MRI). Furthermore, in vitro and vivo results indicate that the TLDCAG NPs have vigorous antitumor activity and negligible systemic toxicity. Therefore, the TLDCAG NPs provide an efficient strategy for enhancing antitumor efficacy.


Assuntos
Nanopartículas , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Espécies Reativas de Oxigênio
20.
J Colloid Interface Sci ; 603: 783-798, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34246838

RESUMO

The targeting dual-responsive drug delivery system was employed for cancer treatment as a positive strategy. Herein, Lactobionic acid (LA)-modified and non-modified UV/reduction dual-responsive molecules (10,10-NB-S-S-P-LA and 10,10-NB-S-S-P-OMe) were synthesized. Functional magnetic resonance imaging (MRI) contrast agent (12,12-NB-DTPA-Gd) was mixed with 10,10-NB-S-S-P-LA or 10,10-NB-S-S-P-OMe in the optimal ratio (3:1) to develop targeted empty liposomes (GNSPL) or non-targeted empty liposomes (GNSPM) with superior UV/reduction dual-responsiveness, biocompatibility and magnetic resonance imaging (MRI) performance. The drug-loaded liposomes (GNSPLD and GNSPMD) can keep stable in two weeks, and the drug cumulative release rate reached to the maximum under dual stimulation of ultraviolet (UV) and reducing agent (TCEP). The treatment with GNSPLD + UV significantly inhibited the growth and migration of cancer cells in vitro. The GNSPLD liposomes were more effectively accumulated in tumor site than GNSPMD liposomes, due to the targeting property of GNSPLD liposomes. The treatment with GNSPLD + UV showed a better therapeutic efficacy than Doxorubicin (DOX) in vivo, and almost no side effects during the treatment period. Thus, the MRI-guided targeting dual-responsive drug delivery system provided a reliable therapeutic strategy for treating liver cancer.


Assuntos
Sistemas de Liberação de Medicamentos , Neoplasias Hepáticas , Doxorrubicina/farmacologia , Humanos , Lipossomos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/tratamento farmacológico , Imageamento por Ressonância Magnética
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