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1.
Nano Lett ; 21(22): 9543-9550, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34762431

RESUMO

We investigated the magnetic effect of Mn2+ ions on an exciton of Mn-doped CsPbI3 quantum dots (QDs), where we looked for the signatures of an exciton magnetic polaron known to produce a large effective magnetic field in Mn-doped CdSe QDs. In contrast to Mn-doped CdSe QDs that can produce ∼100 T of magnetic field upon photoexcitation, manifested as a large change in the energy and relaxation dynamics of a bright exciton, Mn-doped CsPbI3 QDs exhibited little influence of a magnetic dopant on the behavior of a bright exciton. However, a µs-lived dark exciton in CsPbI3 QDs showed 40% faster decay in the presence of Mn2+, equivalent to the effect of ∼3 T of an external magnetic field. While further study is necessary to fully understand the origin of the large difference in the magneto-optic property of an exciton in two systems, we consider that the difference in antiferromagnetic coupling of the dopants is an important contributing factor.

2.
Chem Commun (Camb) ; 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34812448

RESUMO

We report here a catalytically active nano covalent organic framework [COF(Fe)] with high drug loading capacity for reversing tumor multidrug resistance (MDR). The Fe catalytic sites in COF(Fe) could convert intracellular overexpressed H2O2 into highly reactive ˙OH to induce oxidation stress and down-regulate MDR protein. Therefore, COF(Fe) could enhance the intracellular drug accumulation to overcome MDR, which was demonstrated both in vitro and in vivo.

3.
Anal Chem ; 93(40): 13734-13741, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34605236

RESUMO

Precisely detecting biomarkers in living systems holds tremendous promise for disease diagnosis and monitoring. Herein, we developed a covalent organic framework (COF)-based tricolor fluorescent nanoprobe for simultaneously imaging biomarkers with different spatial locations in living cells. Briefly, a TAMRA-labeled survivin mRNA antisense nucleotide and a Cy5-labeled transmembrane glycoprotein mucin 1 (MUC1) aptamer were adsorbed on a nanoscale fluorescent COF. To enhance the interactions between COF nanoparticles (NPs) and nucleic acid molecules, a freezing method was employed for improving the nucleic acid loading density and ensuring detection performance. The fluorescence signals of dyes on DNAs were first quenched by the COF NPs. Internalization and distribution of the nanoprobes can be real-time visualized by the autofluorescence of COF NPs. In living cells, recognition between MUC1 with MUC1 aptamers causes fluorescence signal recovery of Cy5, while hybridization between survivin mRNA and its antisense DNA induces the signal recovery of TAMRA. Therefore, this COF-based multicolor nanoprobe could be employed for visualizing MUC1 on the cell membrane and survivin mRNA in the cytoplasm. Cancer cell-specific diagnostic imaging and monitoring of the process of cancer cell exosomes infecting normal cells using the nanoprobe were achieved. This work not only offers a versatile nanoprobe for bioanalysis but also provides new insights for developing novel COF-based nanoprobes.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Ácidos Nucleicos , DNA , Corantes Fluorescentes , Imagem Óptica
4.
Nat Commun ; 12(1): 6046, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663832

RESUMO

When hitting interfaces between two different media, light beams may undergo small shifts. Such beam shifts cannot be described by the geometrical optics based on Snell's law and their underlying physics has attracted much attention. Conventional beam shifts like Goos-Hänchen shifts and Imbert-Fedorov shifts not only require obliquely incident beams but also are mostly very small compared to the wavelength and waist size of the beams. Here we propose a method to realize large and controllable polarization-dependent lateral shifts for normally incident beams with photonic crystal slabs. As a proof of the concept, we engineer the momentum-space geometric phase distribution of a normally incident beam by controlling its interaction with a photonic crystal slab whose momentum-space polarization structure is designed on purpose. The engineered geometric phase distribution is designed to result in a large shift of the beam. We fabricate the designed photonic crystal slab and directly observe the beam shift, which is ~5 times the wavelength and approaches the waist radius. Based on periodic structures and only requiring simple manipulation of symmetry, our proposed method is an important step towards practical applications of beam shifting effects.

5.
Chem Commun (Camb) ; 57(91): 12087-12097, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34714302

RESUMO

Inducing the immunogenic cell death (ICD) of cancer cells is an important method to improve the immunogenicity of tumor cells for enhanced cancer immunotherapy. Therefore, we discuss the ICD process and then highlight various ICD inducers and strategies for triggering the ICD of cancer cells. We hope that this Feature Article will inspire readers to develop more effective ICD inducers.

6.
Reprod Sci ; 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34515984

RESUMO

Adenomyosis is a benign disease with a malignant behavior, bothering a lot of women at reproductive age who suffer from increased menstruation, prolonged menstruation, progressive dysmenorrhea, and infertility. At present, there is no effective treatment for adenomyosis. It seriously affects the life quality of these patients. However, the pathogenesis of adenomyosis is not yet clear. Recently, uterus junctional zone, defined as the inner 1/3 of myometrium between endometrium and myometrium, has gained broad attention. As is reported, the structure and function disorder of uterus junctional zone may play an important part in the occurrence and development of adenomyosis. In this issue, the present study generally reviews the role of uterine junction zone and the related mechanisms involved in adenomyosis, such as the local micro-damage, the formation of inflammatory and hypoxic microenvironment, changes of cytokines, and abnormalities of miRNA as well as signal pathways. It will provide new insights and potential therapeutic target strategies for clinical strategies in the management of adenomyosis.

7.
Nano Lett ; 21(18): 7862-7869, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34494442

RESUMO

Blocking energy metabolism of cancer cells and simultaneously stimulating the immune system to perform immune attack are significant for cancer treatment. However, how to potently deliver different drugs with these functions remains a challenge. Herein, we synthesized a nanoprodrug formed by a F127-coated drug dimer to inhibit glycolysis of cancer cells and alleviate the immunosuppressive microenvironment. The dimer was delicately constructed to connect lonidamine (LND) and NLG919 by a disulfide bond which can be cleaved by excess GSH to release two drugs. LND can decrease the expression of hexokinase II and destroy mitochondria to restrain glycolysis for energy supply. NLG919 can reduce the accumulation of kynurenine and the number of regulatory T cells, thus alleviating the immunosuppressive microenvironment. Notably, the consumption of GSH by disulfide bond increased the intracellular oxidative stress and triggered immunogenic cell death of cancer cells. This strategy can offer more possibilities to explore dimeric prodrugs for synergistic cancer therapy.


Assuntos
Antineoplásicos , Neoplasias , Pró-Fármacos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Glicólise , Morte Celular Imunogênica , Imunossupressão , Neoplasias/tratamento farmacológico , Polímeros/uso terapêutico , Pró-Fármacos/uso terapêutico
9.
Phys Rev Lett ; 127(4): 043901, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34355949

RESUMO

We report the observation of polarization singularities in momentum space of 2D photonic quasicrystal slabs. Supercell approximation and band-unfolding approach are applied to obtain approximate photonic dispersions and the far-field polarization states defined on them. We discuss the relations between the topological charges of the polarization vortex singularities at Γ points and the symmetries of photonic quasicrystal slabs. With a perspective of multipolar expansions for the supercell, we confirm that the singularities are protected by the point-group symmetry of the photonic quasicrystal slab. We further uncover that the polarization singularities of photonic quasicrystal slab correspond to quasibound states in the continuum with exceptionally high-quality factors. Polarization singularities of different topological charges are also experimentally verified. Our Letter introduces core concepts of optical singularities into quasiperiodic systems, providing new platforms for explorations merging topological and singular optics.

10.
Anal Chem ; 93(34): 11751-11757, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34398599

RESUMO

Developing nanoplatforms that simultaneously integrate diagnostic imaging and therapy functions has been a promising but challenging task for cancer theranostics. Herein, we report the rational design of a smart nucleic acid-gated covalent organic framework (COF) nanosystem for cancer-specific imaging and microenvironment-responsive drug release. Cy5 dye-labeled single-stranded DNA (ssDNA) for mRNA recognition was adsorbed on the surface of doxorubicin (Dox)-loaded COF nanoparticles (NPs). Dox loaded in the pores of COF NPs could strengthen the interactions between ssDNA and COF and enhance the fluorescence quenching effect toward Cy5, while the densely coated ssDNA could prevent the leakage of Dox from COF NPs. The obtained nanosystem exhibited low fluorescence signal and Dox release in normal cells; however, the ssDNA could be released by the overexpressed TK1 mRNA in cancer cells to recover the intense fluorescence signal of Cy5, and the loaded Dox could be further released for chemotherapy. Therefore, cancer cell-specific diagnostic imaging and drug release were realized with the rationally developed nanosystem. This work offers a universal nanoplatform for cancer theranostics and a promising strategy for regulating the interaction between COFs and biomolecules.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Ácidos Nucleicos , Diagnóstico por Imagem , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
11.
Anal Chem ; 93(35): 12096-12102, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34432421

RESUMO

Developing spherical nucleic acids with new structures holds great promise for nanomedicine and bioanalytical fields. Covalent organic frameworks (COFs) are emerging promising materials with unique properties for a wide range of applications. However, devising COF-based spherical nucleic acid is challenging because methods for the preparation of functionalized COFs are still limited. We report here a bonding defect-amplified modification (BDAM) strategy for the facile preparation of functionalized COFs. Poly(acrylic acid) was employed as the defect amplifier to modify the surface of COF nanoparticles by the formation of amide bonds with amino residues, which successfully converted and amplified the residues into abundant reactive carboxyl groups. Then, amino terminal-decorated hairpin DNA was densely grafted onto the surface of COF nanoparticles (NPs) to give rise to a spherical nucleic acid probe (SNAP). A series of experiments and characterizations proved the successful preparation of the COF-based SNAP, and its application in specifically lighting up RNA biomarkers in living cells for cancer diagnostic imaging was demonstrated. Therefore, the COF-based SNAP is a promising candidate for biomedical applications and the proposed BDAM represents a useful strategy for the preparation of functionalized COFs for diverse fields.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Ácidos Nucleicos , DNA/genética , Sondas de Ácido Nucleico
12.
Biomed Res Int ; 2021: 5529368, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34368350

RESUMO

The aim of this study was to evaluate the biocompatibility and osteogenic potential of a Zeolite Socony Mobil-5 (ZSM-5) coating on a Ti-24 Nb-4 Zr-7.9 Sn (Ti-2448) surface. ZSM-5-modified Ti-2448 (ZSM-5/Ti-2448) and Ti-2448 (control) groups were employed. The physical and chemical properties of the two types of samples were evaluated by scanning electron microscopy, Fourier-transform infrared spectroscopy, nitrogen adsorption/desorption, and contact angle methods. The surface of the ZSM-5/Ti-2448 was rougher than that of the original Ti-2448, while the contact angle of the ZSM-5/Ti-2448 was smaller than that of Ti-2448. In addition, the ZSM-5/Ti-2448 largely increased the specific surface area and introduced silanol groups. A bone-like apatite layer could be formed on the surface of ZSM-5/Ti-2448 after 14 days of incubation in a simulated body fluid. ZSM-5/Ti-2448 was not cytotoxic. The number and alkaline phosphatase (ALP) activity of osteoblasts on ZSM-5/Ti-2448 were significantly higher than those on Ti-2448 surfaces, obtained in vitro using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide and ALP activity assays. Few inflammatory cells were observed around ZSM-5/Ti-2448 after insertion into the femurs of Japanese white rabbits after 4, 12, and 26 weeks through hematoxylin-eosin staining. The average gray scale of transforming growth factor-ß1 (TGF-ß1) on ZSM-5/Ti-2448 peaked earlier than that on Ti-2448, according to immunohistochemical staining. These results indicate that ZSM-5/Ti-2448 has a good biocompatibility and improved early osteogenic potential compared to a noncoated Ti-2448.


Assuntos
Ligas/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Osteogênese/efeitos dos fármacos , Zeolitas/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Biomineralização/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Implantes Experimentais , Masculino , Camundongos , Coelhos , Propriedades de Superfície , Fator de Crescimento Transformador beta/metabolismo
13.
ACS Appl Mater Interfaces ; 13(35): 41498-41506, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34435498

RESUMO

Covalent organic frameworks (COFs) have emerged as promising materials for biomedical applications, but their functions remain to be explored and the potential toxicity concerns should be resolved. Herein, it is presented that carbonization significantly enhances the fluorescence quenching efficiency and aqueous stability of nanoscale COFs. The probes prepared by physisorbing dye-labeled nucleic acid recognition sequences onto the carbonized COF nanoparticles (termed C-COF) were employed for cell imaging, which could effectively light up biomarkers (survivin and TK1 mRNA) in living cells. The C-COF has enhanced photothermal conversion capacity, indicating that the probes are also promising candidates for photothermal therapy. The potential toxicity concern from the aromatic rigid building units of COFs was detoured by carbonization. Overall, carbonization is a promising strategy for developing biocompatible and multifunctional COF-derived nanoprobes for biomedical applications. This work may inspire more versatile COF-derived nanoprobes for bioanalysis and nanomedicine.

14.
Adv Healthc Mater ; 10(18): e2100703, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34363332

RESUMO

Metal-organic nanomaterials have emerged as promising therapeutic agents to produce reactive oxygen species (ROS) under ultrasound (US) or light irradiation for tumor treatments. However, their relatively large sizes (ranging from tens to hundreds of nanometers) usually lead to low ROS utilization and body metabolism, thus enlarging their long-term toxicity and low therapeutic effect. To solve these shortcomings, herein the ultrasmall Gd3+ -hemoporfin framework nanodots (GdHF-NDs, ≈5 nm) is reported as efficient nano-sonosensitizers. Compared with GdHF aggregation (GdHF-A, ≈400 nm), the ultrasmall GdHF-NDs generate 2.3-fold toxic ROS amount under similar conditions, due to shorter diffusion path and larger relative specific surface area. When the GdHF-NDs dispersion is introvenously injected into tumor-bearing mouse, they are accumulated within tumors to provide high magnetic resonance imaging (MRI) contrast. Under US irradiation, the GdHF-NDs achieve a better sonodynamic therapeutic efficacy for tumors, compared with that from GdHF-A. More importantly, owing to ultrasmall size, most of GdHF-NDs can be rapidly cleared through the renal pathway. Therefore, GdHF-NDs can be used as a biosafety and high-performance sonodynamic agent for cancer theranostics.


Assuntos
Nanopartículas , Nanoestruturas , Neoplasias , Animais , Linhagem Celular Tumoral , Hematoporfirinas , Camundongos , Medicina de Precisão
15.
Clin Epigenetics ; 13(1): 166, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34452630

RESUMO

DNA methylation, an epigenetic modification, regulates gene transcription and maintains genome stability. DNA methyltransferase (DNMT) inhibitors can activate silenced genes at low doses and cause cytotoxicity at high doses. The ability of DNMT inhibitors to reverse epimutations is the basis of their use in novel strategies for cancer therapy. In this review, we examined the literature on DNA methyltransferase inhibitors. We summarized the mechanisms underlying combination therapy using DNMT inhibitors and clinical trials based on combining hypomethylation agents with other chemotherapeutic drugs. We also discussed the efficacy of such compounds as antitumor agents, the need to optimize treatment schedules and the regimens for maximal biologic effectiveness. Notably, the combination of DNMT inhibitors and chemotherapy and/or immune checkpoint inhibitors may provide helpful insights into the development of efficient therapeutic approaches.

16.
Entropy (Basel) ; 23(6)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203696

RESUMO

Bayesian Networks structure learning (BNSL) is a troublesome problem that aims to search for an optimal structure. An exact search tends to sacrifice a significant amount of time and memory to promote accuracy, while the local search can tackle complex networks with thousands of variables but commonly gets stuck in a local optimum. In this paper, two novel and practical operators and a derived operator are proposed to perturb structures and maintain the acyclicity. Then, we design a framework, incorporating an influential perturbation factor integrated by three proposed operators, to escape current local optimal and improve the dilemma that outcomes trap in local optimal. The experimental results illustrate that our algorithm can output competitive results compared with the state-of-the-art constraint-based method in most cases. Meanwhile, our algorithm reaches an equivalent or better solution found by the state-of-the-art exact search and hybrid methods.

17.
Light Sci Appl ; 10(1): 154, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315850

RESUMO

Inferring the properties of a scattering objective by analyzing the optical far-field responses within the framework of inverse problems is of great practical significance. However, it still faces major challenges when the parameter range is growing and involves inevitable experimental noises. Here, we propose a solving strategy containing robust neural-networks-based algorithms and informative photonic dispersions to overcome such challenges for a sort of inverse scattering problem-reconstructing grating profiles. Using two typical neural networks, forward-mapping type and inverse-mapping type, we reconstruct grating profiles whose geometric features span hundreds of nanometers with nanometric sensitivity and several seconds of time consumption. A forward-mapping neural network with a parameters-to-point architecture especially stands out in generating analytical photonic dispersions accurately, featured by sharp Fano-shaped spectra. Meanwhile, to implement the strategy experimentally, a Fourier-optics-based angle-resolved imaging spectroscopy with an all-fixed light path is developed to measure the dispersions by a single shot, acquiring adequate information. Our forward-mapping algorithm can enable real-time comparisons between robust predictions and experimental data with actual noises, showing an excellent linear correlation (R2 > 0.982) with the measurements of atomic force microscopy. Our work provides a new strategy for reconstructing grating profiles in inverse scattering problems.

18.
Chem Sci ; 12(9): 3130-3145, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34164080

RESUMO

Cancer immunotherapy is a revolutionary treatment method in oncology, which uses a human's own immune system against cancer. Many immunomodulators that trigger an immune response have been developed and applied in cancer immunotherapy. However, there is the risk of causing an excessive immune response upon directly injecting common immunomodulators into the human body to trigger an immune response. Therefore, the development of intelligent stimuli-responsive immunomodulators to elicit controlled immune responses in cancer immunotherapy is of great significance. Nanotechnology offers the possibility of designing smart nanomedicine to amplify the antitumor response in a safe and effective manner. Progress relating to intelligent stimuli-responsive nano immunomodulators for cancer immunotherapy is highlighted as a new creative direction in the field. Considering the clinical demand for cancer immunotherapy, we put forward some suggestions for constructing new intelligent stimuli-responsive nano immunomodulators, which will advance the development of cancer immunotherapy.

19.
Biology (Basel) ; 10(6)2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-34071147

RESUMO

Hepatopancreas necrosis disease (HPND) of the Chinese mitten crab Eriocheir sinensis causes huge economic loss in China. However, the pathogenic factors and pathogenesis are still a matter of dissension. To search for potential pathogens, the hepatopancreatic flora of diseased crabs with mild symptoms, diseased crabs with severe symptoms, and crabs without visible symptoms were investigated using metatranscriptomics sequencing. The prevalence of Absidia glauca and Candidatus Synechococcus spongiarum decreased, whereas the prevalence of Spiroplasma eriocheiris increased in the hepatopancreatic flora of crabs with HPND. Homologous sequences of 34 viral species and 4 Microsporidian species were found in the crab hepatopancreas without any significant differences between crabs with and without HPND. Moreover, DEGs in the hepatopancreatic flora between crabs with severe symptoms and without visible symptoms were enriched in the ribosome, retinol metabolism, metabolism of xenobiotics by cytochrome P450, drug metabolism-cytochrome P450, biosynthesis of unsaturated fatty acids, and other glycan degradation. Moreover, the relative abundance of functions of DEDs in the hepatopancreatic flora changed with the pathogenesis process. These results suggested that imbalance of hepatopancreatic flora was associated with crab HPND. The identified DEGs were perhaps involved in the pathological mechanism of HPND; nonetheless, HPND did not occur due to virus or microsporidia infection.

20.
ACS Appl Mater Interfaces ; 13(27): 31440-31451, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34184531

RESUMO

Activatable nanoscale drug delivery systems (NDDSs) are promising in maximizing cancer specificity and anticancer efficacy, and a multifunctional metal-organic nanomaterial is one of the new star NDDSs which requires further exploration. Herein, a novel DOX@MnCPs/PEG NDDSs were constructed by first synthesizing Mn3+-sealed coordination particles (MnCPs), modified with a targeted PEGylated polymer, and then loading anticancer drug doxorubicin (DOX). MnCPs were prepared from the assembly of Mn3+ ions and hematoporphyrin monomethyl ether (HMME) molecules. Furthermore, MnCPs had an average size of ∼100 nm and a large surface area (∼52.6 m2 g-1) and porosity (∼3.6 nm). After the loading of DOX, DOX@MnCPs/PEG exhibited a high DOX-loading efficacy of 27.2%, and they reacted with glutathione (GSH) to confer structural collapse, leading to the production of Mn2+ ions for enhanced magnetic resonance imaging (MRI), free HMME for augmented photodynamic effect, and free DOX for chemotherapy. As a consequence, these DOX@MnCPs/PEG NDDSs after intravenous injection showed efficient tumor homing and then exerted an obvious suppression for tumor growth rate by synergistic photodynamic-chemo therapy in vivo. Importantly, most of the DOX@MnCPs/PEG NDDSs could be gradually cleared through the renal pathway, and the remaining part could slowly be metabolized via the feces, enabling high biosafety. Therefore, this work provides a type of GSH-sensitive NDDS with biosafety, caner specificity, and multifunctionality for high synergistic treatment efficacy.


Assuntos
Doxorrubicina/química , Portadores de Fármacos/química , Glutationa/metabolismo , Manganês/química , Nanoestruturas/química , Fotoquimioterapia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Humanos , Polietilenoglicóis/química , Segurança
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