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1.
BMC Health Serv Res ; 24(1): 1167, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39363315

RESUMO

BACKGROUND AND AIM: China has used traditional Chinese medicine (TCM) to treat diseases for more than 2000 years. Traditionally, TCMs in medicine cabinets are arranged alphabetically or on the basis of experience, but this arrangement greatly affects dispensing efficiency. However, owing to the unique properties and qualities of TCM, very few automatic approaches or systems have specifically addressed TCM dispensing problems. Therefore, it is necessary to establish a method of optimizing the traditional Chinese medicine placement scheme (TCMPS) via computer algorithms to improve the work efficiency of pharmacists. METHODS: A prescription dataset from a hospital in 2022 was obtained, and the association rule algorithm (ARA) was used to calculate the frequency of use for each type of TCM and the associations between different types of TCMs. On the basis of these association and frequency data, the optimal TCMPS was calculated using the simulated annealing algorithm (SAA) and then verified using the prescription dataset from 2023. RESULTS: A total of 10,601 prescriptions were collected in 2022, involving 360 different TCMs, and each prescription contained an average of 9.485 TCMs, with Danggui (3628) being the most frequently used. When the threshold of support was set to 0.05 and the confidence was set to 0.8, 78 couplet medicines used in orthopedics clinics were found through ARA. When the threshold value of support was set to 0, the confidence was set to 0, and the rule length was 2, a total of 129,240 rules were obtained, indicating support between all pairwise TCMs. The TCMPS, calculated using SAA, had a correlation sum of 14.183 and a distance sum of 3.292. The TCMPS was verified using a prescription dataset from 2023 and theoretically improved the dispensing efficiency of pharmacists by approximately 50%. CONCLUSIONS: In this study, the ARA and SAA were successfully applied to pharmacies for the first time, and the optimal TCMPS was calculated. This approach not only significantly improves the dispensing efficiency of pharmacists and reduces patient waiting time but also enhances the quality of medical services and patient satisfaction, and provides a valuable reference for the development of smart medicine.


Assuntos
Algoritmos , Medicina Tradicional Chinesa , Medicina Tradicional Chinesa/métodos , Humanos , China , Serviço de Farmácia Hospitalar , Medicamentos de Ervas Chinesas/normas , Medicamentos de Ervas Chinesas/uso terapêutico , Prescrições de Medicamentos/estatística & dados numéricos , Prescrições de Medicamentos/normas
2.
BMC Psychiatry ; 23(1): 107, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36793025

RESUMO

BACKGROUND: Older adults' psychological health is a public health issue that cannot be ignored, especially when these psychological health problems and related factors change across different social backgrounds because of rapid changes in traditions and family structures and the epidemic responses after the outbreak of COVID-19 in China. The aim of our study is to determine the prevalence of anxiety and depression and their associated factors among community-dwelling older adults in China. METHODS: A cross-sectional study was conducted from March to May 2021 with 1173 participants aged 65 years or above from three communities in Hunan Province, China who were selected using convenience sampling. A structured questionnaire including sociodemographic characteristics, clinical characteristics, the Social Support Rating Scale (SSRS), the 7-Item Generalized Anxiety Disorder scale (GAD-7), and the Patient Health Questionnaire-9 Item (PHQ-9) was used to collect relevant demographic and clinical data and to measure social support status, anxiety symptoms, and depressive symptoms, respectively. Bivariate analyses were conducted to explore the difference in anxiety and depression based on samples' different characteristics. The multivariable logistic regression analysis was performed to test for significant predictors of anxiety and depression. RESULTS: The prevalence of anxiety and depression were 32.74% and 37.34%, respectively. Multivariable logistic regression analysis revealed that being female, being unemployed before retirement age, lacking physical activity, having physical pain, and having three or more comorbidities were significant predictors for anxiety. Subjective social support and support utilization were significant protective factors. Regarding depression, religion, lacking physical activity, having physical pain, having three or more comorbidities were found to be significant predictors. Support utilization was a significant protective factor. CONCLUSIONS: The study group showed a high prevalence of anxiety and depression. Gender, employment status, physical activity, physical pain, comorbidities, and social support were associated with psychological health problems of older adults. These findings suggest that governments should focus on the psychological health problems of older adults by raising community awareness of issues related to older adults' psychological health. They should also screen for anxiety and depression among high-risk groups and encourage individuals to seek supportive counseling.


Assuntos
Ansiedade , Depressão , Idoso , Feminino , Humanos , Masculino , Ansiedade/epidemiologia , Ansiedade/psicologia , China/epidemiologia , COVID-19/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Depressão/psicologia , Prevalência
3.
Opt Express ; 30(7): 11444-11458, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35473088

RESUMO

Active phase-control metasurfaces show outstanding capability in the active manipulation of light propagation, while the previous active phase control methods have many constraints in the cost of simulation or the phase modulation range. In this paper, we design and demonstrate a phase controlled metastructure based on two circular split ring resonators (CSRRs) composed of silicon and Au with different widths, which can continuously achieve an arbitrary Pancharatnam-Berry (PB) phase between -π and π before or after active control. The PB phase of such a metasurface before active control is determined by the rotation angle of the Au-composed CSRR, while the PB phase after active control is determined by the rotation angle of the silicon-composed CSRR. And active control of the PB phase is realized by varying conductivity of silicon under an external optical pump. Based on this metastructure, active control of light deflection, metalens with arbitrary reconfigurable focal points and achromatic metalens under selective frequencies are designed and simulated. Moreover, the experimental results demonstrate that focal spots of metalens can be actively controlled by the optical pump, in accord with the simulated ones. Our metastructure implements a plethora of metasurfaces' active phase modulation and provides applications in active light manipulation.

4.
FASEB J ; 34(9): 12177-12196, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32716585

RESUMO

miR-375-3p is a significantly downregulated miRNA in bladder cancer (BC). However, its role in BC regulation is still unclear. In this study, we reported that miR-375-3p overexpression inhibited proliferation and migration and promoted apoptosis in BC cells. Frizzled-8 (FZD8) gene is identified as the direct miR-375-3p targeting gene. miR-375-3p blocks the Wnt/ß-catenin pathway and downstream molecules Cyclin D1 and c-Myc by inhibiting the expression of FZD8 directly, it could increase caspase 1 and caspase 3 expression and promote T24 cell apoptosis as well. miR-375-3p also showed a significant inhibitory effect in vivo in bladder tumor-bearing nude mice, as demonstrated by the reduced tumor volume and Ki67 proliferation index in tumor tissue. Collectively, miR-375-3p is a suppressor of BC that inhibits proliferation and metastasis, and promotes apoptosis in BC cells as well as suppresses tumor growth in a T24 xenograft mouse model, which could be used as a potential therapeutic approach for BC in future.


Assuntos
Exossomos/fisiologia , Genes Supressores de Tumor/fisiologia , MicroRNAs/fisiologia , Neoplasias da Bexiga Urinária/prevenção & controle , Via de Sinalização Wnt/fisiologia , Animais , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Receptores de Superfície Celular/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Phys Chem Chem Phys ; 23(26): 14195-14204, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34159999

RESUMO

The two-dimensional counterpart of diamond, diamane, has attracted increasing interest due to its potentially distinctive properties. In this paper, diamanes anchored with different anion groups have been systematically studied with density functional theory (DFT) for the first time. Among them 12 conformers are confirmed to be stable and present direct semiconductor features with bandgaps ranging from 2.527 eV to 4.153 eV, and the in-plane stiffness is larger than that of graphene. Moreover, the electron carrier mobility of chair2-F is exceptionally high at 16546.713 cm2 V-1 s-1 along the y-direction, which is remarkably larger than that of diamond; and N-, B-doped boat2-H can be doped to have n-, p-type conductivity with a moderate activation energy of 0.34 and 0.37 eV, respectively. This work suggests that functionalized diamanes are promising for electronic devices and engineering materials.

6.
Molecules ; 26(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279368

RESUMO

The purpose of this study was to identify new metal-based anticancer drugs; to this end, we synthesized two new copper(II) complexes, namely [Cu(ncba)4(phen)] (1) and [Cu(ncba)4(bpy)] (2), comprised 4-chloro-3-nitrobenzoic acid as the main ligand. The single-crystal XRD approach was employed to determine the copper(II) complex structures. Binding between these complexes and calf thymus DNA (CT-DNA) and human serum albumin (HSA) was explored by electronic absorption, fluorescence spectroscopy, and viscometry. Both complexes intercalatively bound CT-DNA and statically and spontaneously quenched DNA/HSA fluorescence. A CCK-8 assay revealed that complex 1 and complex 2 had substantial antiproliferative influences against human cancer cell lines. Moreover, complex 1 had greater antitumor efficacy than the positive control cisplatin. Flow cytometry assessment of the cell cycle demonstrated that these complexes arrested the HepG2 cell cycle and caused the accumulation of G0/G1-phase cells. The mechanism of cell death was elucidated by flow cytometry-based apoptosis assays. Western blotting revealed that both copper(II) complexes induced apoptosis by regulating the expression of the Bcl-2(Bcl-2, B cell lymphoma 2) protein family.


Assuntos
Antineoplásicos/síntese química , Clorobenzoatos/química , Complexos de Coordenação/síntese química , Cobre/química , Albumina Sérica Humana/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/farmacologia , DNA/química , Células Hep G2 , Humanos
7.
Opt Express ; 27(12): 16624-16634, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31252886

RESUMO

A novel electromagnetically induced transparency (EIT) all-dielectric metamaterial is proposed, fabricated, and characterized. The unit cell of the proposed metamaterial comprises of two asymmetric split ring resonators (a-SRRs) positioned with a mirror symmetry. The asymmetric nature of a-SRRs results from the length difference of two arcs. Optical properties of the fabricated metamaterial are investigated numerically using finite difference method, as well as experimentally using a terahertz time-domain spectroscopy. The results confirm that the proposed metamaterial exhibits an EIT transparent window in the frequency range around 0.78THz with a Q-factor of ~75.7 and a time-delay up to ~28.9ps. Theoretical investigations show that EIT effects in our metamaterial are achieved by hybridizing two bright modes in the same unit cell, which are aroused by the excitation of magnetic moments. We also confirm that the proposed metamaterial has great potential for sensing applications with high sensitivity and high figure of merit (FOM), which guarantees potential applications in in situ chemical and biological sensing.

8.
Opt Express ; 27(4): 5217-5229, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30876123

RESUMO

In this paper, a mid-infrared perfect absorber based on the dual gratings-coupled graphene-dielectric multilayer structures (DGC-GDM) is proposed, in which GDM is sandwiched between two Au gratings. The DGC-GDM absorber shows advantages of dual-band and tunable absorption, insensitive to polarization, ultrathin thickness and wide angle range absorption. Two kinds of SPPs in the GDM layer can be excited by the upper and lower Au gratings, respectively, which confine the incident light into the GDM and thus contribute to the dual-band absorption. The wavelength of the absorption peak can be effectively changed by varying the Fermi level of graphene. Most importantly, an analytic formulas describing the relationships between the parameters of the absorber and the absorption spectra is derived. And the accuracy of the theoretical formulas is verified by comparing the simulation results with the theoretically calculated ones. Therefore, the exact values of parameters of the structure for an absorption peak as required can be obtained. The proposed structure can be applied to absorbers that are working at other frequencies.

9.
Exp Cell Res ; 363(2): 141-150, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29269076

RESUMO

Extracellular vesicles (EVs) are nano vesicular structures that are secreted by almost all kinds of cells. Exosomes are small EVs derived from endosomes, with a diameter between 30-100nm. Tumour-derived exosomes carry many molecules and factors from tumour cells. These exosomes are recognized and taken up by immunocytes. However, tumour-derived exosomes can not only suppress immune cell functions but also help tumours escape immune surveillance in the tumour microenvironment. The present work investigated the effect of exosomes derived from genetical modified K562 cells (GMK cells), which express IL-15, IL-18 and 4-1BBL (TNFSF9) on their surface. The results showed that these GME exosomes, carrying IL-15, IL-18 and 4-1BBL proteins similar to their host cells, could activate NK cells, increase the cytotoxicity of NK cells on some tumour cells in a short treatment (4h) and promote NK cells proliferation. However, with an extended treatment time (48h), these exosomes could inhibite the cytotoxicity of NK cells by inhibiting activated receptor expression on NK cells. These results indicated the bifacial effects of GMK exosomes on NK cells, which will be helpful to explore the possibility of using transformed exosomes as an anti-tumour immune vaccine or a therapeutic tool in future.


Assuntos
Engenharia Celular , Citotoxicidade Imunológica/imunologia , Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Células Matadoras Naturais/imunologia , Engenharia Celular/métodos , Proliferação de Células/fisiologia , Humanos , Células K562 , Transdução de Sinais/fisiologia , Microambiente Tumoral/fisiologia
10.
Opt Express ; 26(6): 7842-7851, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29609332

RESUMO

Two (La0.7Sr0.3MnO3)n/(SrTiO3)m superlattices with different superlattice period but the same total thickness were deposited on LaAlO3 substrates by pulsed laser deposition. Dielectric properties of these samples were investigated by means of terahertz time-domain spectroscopy (THz-TDS) under external continuous wave green laser excitation and optical-pump terahertz-probe spectroscopy (OPTP) at room temperature. Experimental results show that the real part of the permittivity for both superlattices increases significantly with increasing green laser pump power, which indicates the decrease of the plasma frequency, along with the increase of the electron scattering rate, soft mode eigenfrequency and oscillator strength in the Drude-Lorentz model. Furthermore, it's observed that the insulating superlattice exhibits a more significant dielectric tunability than the metallic superlattice. Besides, the carrier lifetime of superlattices is much shorter than the La0.7Sr0.3MnO3 thin film in the OPTP measurements, indicating that the electrons excited in the La0.7Sr0.3MnO3 layers may be trapped by the defects located in the interfaces of La0.7Sr0.3MnO3 and SrTiO3 or the SrTiO3 layers. With the optical field-induced tunability of dielectric properties, (La0.7Sr0.3MnO3)n/(SrTiO3)m superlattices show great potential in the actively tunable devices in the THz range.

11.
J Bone Miner Metab ; 36(1): 1-11, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28766139

RESUMO

Extracellular vesicles (EVs) are phospholipid membrane-enclosed entities containing specific proteins, RNA, miRNA, and lncRNA. EVs are released by various cells and play a vital role in cell communication by transferring their contents from the host cells to the recipient cells. The role of EVs has been characterized in a wide range of physiological and pathophysiological processes. In this context, we highlight recent advances in our understanding of the regulatory effects of EVs, with a focus on bone metabolism and the bone microenvironment. The roles of EVs in cell communication among bone-related cells, stem cells, tumor cells, and other cells under physiological or pathological conditions are also discussed. In addition, promising applications for EVs in treating bone-related diseases are proposed.


Assuntos
Osso e Ossos/metabolismo , Microambiente Celular , Vesículas Extracelulares/metabolismo , Animais , Doenças Ósseas/patologia , Humanos , Modelos Biológicos , Células-Tronco/metabolismo
12.
Pharm Biol ; 55(1): 799-809, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28112016

RESUMO

CONTEXT: Sonchus oleraceus L. (Asteraceae) (SO) is a dietary and traditional medicinal plant in China. However, its underlying mechanism of action as an anti-inflammatory agent is not known. OBJECTIVE: This study evaluates the anti-inflammatory activity of aqueous extract of SO. MATERIALS AND METHODS: The extract of SO was used to treat RAW 264.7 cells (in the working concentrations of 500, 250, 125, 62.5, 31.3 and 15.6 µg/mL) for 24 h. Pro-inflammatory cytokines and mediators produced in LPS-stimulated RAW 264.7 cells were assessed. Meanwhile, the expression level of TLR-4, COX-2, pSTATs and NF-κB was tested. Moreover, the anti-inflammatory activity of the extract in vivo was assessed using xylene-induced mouse ear oedema model and the anti-inflammatory compounds in the extracts were analyzed by HPLC-MS. RESULTS: SO extract significantly inhibited the production of pro-inflammatory cytokines and mediators at gene and protein levels with the concentration of 31.3 µg/mL, and suppressed the expression of TLR-4, COX-2, NF-κB and pSTAT in RAW 264.7 cells. The anti-inflammatory activity of SO in vivo has significant anti-inflammatory effects with the concentration of 250 and 125 mg/kg, and less side effect on the weights of the mice at the concentration of 250 mg/kg. Moreover, HPLC-MS analysis revealed that the anti-inflammatory compounds in the extract were identified as villosol, ferulaic acid, ß-sitosterol, ursolic acid and rutin. DISCUSSION AND CONCLUSION: This study indicated that SO extract has anti-inflammatory effects in vitro and in vivo, which will be further developed as novel pharmacological strategies in order to defeat inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Lipopolissacarídeos/farmacologia , Extratos Vegetais/farmacologia , Sonchus , Animais , Sobrevivência Celular/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/farmacologia , Citocinas/antagonistas & inibidores , Citocinas/genética , Masculino , Camundongos , NF-kappa B/análise , Extratos Vegetais/análise , Células RAW 264.7 , Sonchus/química , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/genética
13.
Opt Express ; 24(6): 6606-18, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-27136850

RESUMO

Graphene possesses a unique Landau level system that is non-equidistantly spaced in energy, as thus a large amount of optical transitions may become possible. Here, by utilizing this unique feature, we propose a novel dual field method which combines both external magnetic field and gate electric field together to control the optical response of the graphene-based devices. The key principle of this method is to selectively allow different optical transitions in graphene among Landau levels via an electric gate tuning of the Fermi level. By applying this method to a graphene based amplitude modulator and through an implementation based on transfer matrix method, we numerically demonstrated the well characteristics of switchable modulation on four individual channels, a huge modulation depth up to 80 dB and an extremely low required energy of tuning Fermi level down to 10 meV. Such excellent frequency tunability and gate controlling ability of this dual field method may open up the potential for applications in active optoelectronics, spin optics, ultrafast optics and etc.

15.
Opt Express ; 22 Suppl 6: A1400-11, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25607297

RESUMO

A metallic hole-array structure was inserted into a tandem solar cell structure as an intermediate electrode, which allows a further fabrication of a novel and efficient hybrid organic-inorganic tandem solar cell. The inserted hole-array layer reflects the higher-energy photons back to the top cell, and transmits lower-energy photons to the bottom cell via the extraordinary optical transmission (EOT) effect. In this case light absorption in both top and bottom subcells can be simultaneously enhanced via both structural and material optimizations. Importantly, this new design could remove the constraints of requiring lattice-matching and current-matching between the used two cascaded subcells in a conventional tandem cell structure, and therefore, the tunnel junction could be no longer required. As an example, a novel PCBM/CIGS tandem cell was designed and investigated. A systematic modeling study was made on the structural parameter tuning, with the period ranging from a few hundreds nanometers to over one micrometer. Surface plasmon polaritons, magnetic plasmon polaritons, localized surface plasmons, and optical waveguide modes were found to participate in the EOT and the light absorption enhancement. Impressively, more than 40% integrated power enhancement can be achieved in a variable structural parameter range.


Assuntos
Fontes de Energia Elétrica , Eletrodos , Nanopartículas Metálicas/química , Refratometria/instrumentação , Semicondutores , Energia Solar , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Nanopartículas Metálicas/efeitos da radiação , Nanopartículas Metálicas/ultraestrutura , Modelos Teóricos , Nanoporos/ultraestrutura , Espalhamento de Radiação , Integração de Sistemas
16.
ScientificWorldJournal ; 2014: 959328, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24895681

RESUMO

This paper investigates the recognition of unknown words in Chinese parsing. Two methods are proposed to handle this problem. One is the modification of a character-based model. We model the emission probability of an unknown word using the first and last characters in the word. It aims to reduce the POS tag ambiguities of unknown words to improve the parsing performance. In addition, a novel method, using graph-based semisupervised learning (SSL), is proposed to improve the syntax parsing of unknown words. Its goal is to discover additional lexical knowledge from a large amount of unlabeled data to help the syntax parsing. The method is mainly to propagate lexical emission probabilities to unknown words by building the similarity graphs over the words of labeled and unlabeled data. The derived distributions are incorporated into the parsing process. The proposed methods are effective in dealing with the unknown words to improve the parsing. Empirical results for Penn Chinese Treebank and TCT Treebank revealed its effectiveness.


Assuntos
Vocabulário , Povo Asiático , Humanos , Idioma , Reconhecimento Psicológico
17.
Nanomaterials (Basel) ; 14(14)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39057878

RESUMO

The ligand engineering of inorganic lead halide perovskite quantum dots (PQDs) is an indispensable strategy to boost their photoluminescence stability, which is pivotal for optoelectronics applications. CsPbX3 (X = Cl, Br, I) PQDs exhibit exceptional optical properties, including high color purity and tunable bandgaps. Despite their promising characteristics, environmental sensitivity poses a challenge to their stability. This article reviews the solution-based synthesis methods with ligand engineering. It introduces the impact of factors like humidity, temperature, and light exposure on PQD's instability, as well as in situ and post-synthesis ligand engineering strategies. The use of various ligands, including X- and L-type ligands, is reviewed for their effectiveness in enhancing stability and luminescence performance. Finally, the significant potential of ligand engineering for the broader application of PQDs in optoelectronic devices is also discussed.

18.
Adv Sci (Weinh) ; 11(4): e2305959, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38037307

RESUMO

With the CoO2 slabs consisting of Co4 O4 cubane structure, layered Nax CoO2 are considered promising candidates for oxygen evolution reaction (OER) in alkaline media given their earth-abundant and structural advantages. However, due to the strong adsorption of intermediates on the large basal planes, Nax CoO2 cannot meet the activity demands. Here, a novel one-pot synthesis strategy is proposed to realize the high solubility of iron in Nax CoO2 in an air atmosphere. The optimist Na0.6 Co0.9 Fe0.1 O2 exhibits enhanced OER activity compared to their pristine and other reported Fe-doped Nax CoO2 counterparts. Such an enhancement is mainly ascribed to the abundant active sites on the activated basal planes and the participation of oxidized oxygen as active sites independently, which breaks the scaling relationship limit in the OER process. This work is expected to contribute to the understanding of the modification mechanism of Fe-doped cobalt-based oxides and the exploitation of layer-structured oxides for energy application.

19.
Int J Nanomedicine ; 19: 9613-9635, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39309184

RESUMO

Background: The combination of nanoplatform-based chemotherapy and photodynamic therapy (PDT) is a promising way to treat cancer. Celastrol (Cela) exhibits highly effective anti-hepatoma activity with low water solubility, poor bioavailability, non-tumor targeting, and toxic side effects. The combination of Cela-based chemotherapy and PDT via hepatoma-targeting and reactive oxygen species (ROS)-responsive polymeric micelles (PMs) could solve the application problem of Cela and further enhance antitumor efficacy. Methods: In this study, Cela and photosensitizer chlorin e6 (Ce6) co-loaded glycyrrhetinic acid-modified carboxymethyl chitosan-thioketal-rhein (GCTR) PMs (Cela/Ce6/GCTR PMs) were prepared and characterized. The safety, ROS-sensitive drug release, and intracellular ROS production were evaluated. Furthermore, the in vitro anti-hepatoma effect and cellular uptaken in HepG2 and BEL-7402 cells, and in vivo pharmacokinetic, tissue distribution, and antitumor efficacy of Cela/Ce6/GCTR PMs in H22 tumor-bearing mice were then investigated. Results: Cela/Ce6/GCTR PMs were successfully prepared with nanometer-scale particle size, favorable drug loading capacity, and encapsulation efficiency. Cela/Ce6/GCTR PMs exhibited a strong safety profile and better hemocompatibility, exhibiting less damage to normal tissues. Compared with Cela-loaded GCTR PMs, the ROS-responsiveness of Cela/Ce6/GCTR PMs was increased, and the release of Cela was accelerated after combination with PDT. Cela/Ce6/GCTR PMs can efficiently target liver tumor cells by uptake and have a high cell-killing effect in response to ROS. The combination of GCTR PM-based chemotherapy and PDT resulted in increased bioavailability of Cela and Ce6, improved liver tumor targeting, and better anti-hepatoma effects in vivo. Conclusion: Hepatoma-targeting and ROS-responsive GCTR PMs co-loaded with Cela and Ce6 combined with PDT exhibited improved primary hepatic carcinoma therapeutic effects with lower toxicity to normal tissues, overcoming the limitations of monotherapy and providing new strategies for tumor treatment.


Assuntos
Carcinoma Hepatocelular , Quitosana , Clorofilídeos , Neoplasias Hepáticas , Micelas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Porfirinas , Espécies Reativas de Oxigênio , Animais , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacocinética , Fármacos Fotossensibilizantes/administração & dosagem , Células Hep G2 , Porfirinas/química , Porfirinas/farmacocinética , Porfirinas/farmacologia , Porfirinas/administração & dosagem , Quitosana/química , Quitosana/análogos & derivados , Linhagem Celular Tumoral , Triterpenos Pentacíclicos/farmacologia , Triterpenos Pentacíclicos/farmacocinética , Triterpenos/química , Triterpenos/farmacologia , Triterpenos/farmacocinética , Ácido Glicirretínico/química , Ácido Glicirretínico/farmacologia , Ácido Glicirretínico/farmacocinética , Ácido Glicirretínico/análogos & derivados , Polímeros/química , Distribuição Tecidual , Liberação Controlada de Fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Masculino , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética
20.
ACS Appl Mater Interfaces ; 16(43): 59597-59605, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39432759

RESUMO

Spintronic THz emitters have been widely studied due to their advantages of broadband frequency, high efficiency, and easy fabrication. The spintronic THz signal is proportional to the magnetization of the ferromagnetic (FM) layer and requires an external magnetic field to maximize the THz signal intensity. Recently, a field-free emitter was designed based on a CoFeB/IrMn3 heterostructure via the exchange bias between two films. However, field-free spintronic THz emitters based on a common FM/nonmagnetic metal structure are rare. Here, we fabricate a tunable and field-free THz emitter with giant THz emission modulation ability based on a polyimide/CoFeB/Pt heterostructure. The THz emission can be modulated by changing the curvature radius of the polyimide substrate. After the emitter is forward bent, the THz radiation without an external magnetic field is stronger than in the flat state with a field, which we attribute to in-plane magnetic anisotropy on the FM layer induced by the tensile strain. When we curve the emitter backward, the THz intensity decreases sharply. Moreover, the modulation (ΔS/Smax) of the THz wave from the forward-curved and backward-curved emitter is over 95%, and the device shows good cyclic repeatability. We provide a novel way to design field-free spintronic THz sources, and flexible devices are promising for application in THz devices.

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