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1.
J Mater Chem B ; 12(21): 5207-5219, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38693796

RESUMO

Transarterial chemoembolization (TACE) is widely recognized as a non-surgical treatment approach for advanced liver cancer, combining chemotherapy with the blockage of blood vessels supplying the tumor. To enhance the efficacy of TACE and address chemotherapy resistance, there is growing interest in the development of multifunctional embolic microspheres. In this study, multifunctional PVA microspheres, which encapsulate MIT as a chemotherapeutic drug, PPY as a photothermal agent, and Fe3O4 as a chemodynamic therapy agent, were prepared successfully. The results demonstrated that the developed multifunctional PVA microspheres not only exhibit favorable drug release, photothermal therapy, and chemodynamic therapy performance, but also show a promising synergistic therapeutic effect both in vitro and in vivo. Consequently, the engineered multifunctional PVA microspheres hold tremendous promise for enhancing TACE effectiveness and have the potential to overcome limitations associated with traditional liver cancer treatments.


Assuntos
Quimioembolização Terapêutica , Neoplasias Hepáticas , Microesferas , Terapia Fototérmica , Álcool de Polivinil , Álcool de Polivinil/química , Quimioembolização Terapêutica/métodos , Humanos , Animais , Camundongos , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/tratamento farmacológico , Antineoplásicos/química , Antineoplásicos/farmacologia , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Camundongos Nus
2.
ACS Nano ; 18(12): 9011-9018, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38470156

RESUMO

Topological semimetals have emerged as quantum materials including Dirac, Weyl, and nodal line semimetals, and so on. Dirac nodal line (DNL) semimetals possess topologically nontrivial bands crossing along a line or a loop and are considered precursor states for other types of semimetals. Here, we combine scanning tunneling microscopy/spectroscopy (STM/S) measurements and density functional theory (DFT) calculations to investigate a twist angle tuning of electronic structure in two-dimensional DNL semimetal Au2Ge. Theoretical calculations show that two bands of Au2Ge touch each other in Γ-M and Γ-K paths, forming a DNL. A significant transition of electronic structure occurs by tuning the twist angle from 30° to 24° between monolayer Au2Ge and Au(111), as confirmed by STS measurements and DFT calculations. The disappearing of DNL state is a direct consequence of symmetry breaking.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38403882

RESUMO

Pancreatic cancer, a prevalent malignancy of the digestive system, has a poor 5-year survival rate of around 10%. Although numerous minimally invasive alternative treatments, including photothermal therapy and photodynamic therapy, have shown effectiveness compared with traditional surgical procedures, radiotherapy, and chemotherapy. However, the application of these alternative treatments is constrained by their depth of penetration, making it challenging to treat pancreatic cancer situated deep within the tissue. Sonodynamic therapy (SDT) has emerged as a promising minimally invasive therapy method that is particularly potent against deep-seated tumors such as pancreatic cancer. However, the unique characteristics of pancreatic cancer, including a dense surrounding matrix, high reductivity, and a hypoxic tumor microenvironment, impede the efficient application of SDT. Thus, to guide the evolution of SDT for pancreatic cancer therapy, this review addresses these challenges, examines current strategies for effective SDT enhancement for pancreatic cancer, and investigates potential future advances to boost clinical applicability. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.


Assuntos
Neoplasias , Neoplasias Pancreáticas , Terapia por Ultrassom , Humanos , Neoplasias/terapia , Neoplasias Pancreáticas/terapia , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio , Microambiente Tumoral
4.
Adv Healthc Mater ; 13(4): e2302342, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37975509

RESUMO

Intercellular communication between tumor cells and immune cells regulates tumor progression including positive communication with immune activation and negative communication with immune escape. An increasing number of methods are employed to suppress the dominant negative communication in tumors such as PD-L1/PD-1. However, how to effectively improve positive communication is still a challenge. In this study, a nuclear-targeted photodynamic nanostrategy is developed to establish positive spatiotemporal communication, further activating dual antitumor immunity, namely innate and adaptative immunity. The mSiO2 -Ion@Ce6-NLS nanoparticles (NPs) are designed, whose surface is modified by ionic liquid silicon (Ion) and nuclear localization signal peptide (NLS: PKKKRKV), and their pores are loaded with the photosensitizer hydrogen chloride e6 (Ce6). Ion-modified NPs enhance intratumoral enrichment, and NLS-modified NPs exhibit nuclear-targeted characteristics to achieve nuclear-targeted photodynamic therapy (nPDT). mSiO2 -Ion@Ce6-NLS with nPDT facilitate the release of damaged double-stranded DNA from tumor cells to activate macrophages via stimulator of interferon gene signaling and induce the immunogenic cell death of tumor cells to activate dendritic cells via "eat me" signals, ultimately leading to the recruitment of CD8+ T-cells. This therapy effectively strengthens positive communication to reshape the dual antitumor immune microenvironment, further inducing long-term immune memory, and eventually inhibiting tumor growth and recurrence.


Assuntos
Nanopartículas , Fotoquimioterapia , Linhagem Celular Tumoral , Linfócitos T CD8-Positivos , Fármacos Fotossensibilizantes/farmacologia , Fotoquimioterapia/métodos , Macrófagos , Imunoterapia/métodos , Microambiente Tumoral
5.
Artigo em Inglês | MEDLINE | ID: mdl-37853634

RESUMO

Copper sulfide based phototherapy, including photothermal therapy and photodynamic therapy, is an emerging minimally invasive treatment of tumor, which the light was converted to heat or reactive oxygen to kill the tumor cells. Compared with conventional chemotherapy and radiation therapy, Cu2-x S based phototherapy is more efficient and has fewer side effects. However, considering the dose-dependent toxicity of Cu2-x S, the performance of Cu2-x S based phototherapy still cannot meet the requirement of the clinical application to now. To overcome this limitation, engineering of Cu2-x S to improve the phototherapy performance by increasing light absorption has attracted extensive attention. For better guidance of Cu2-x S engineering, we outline the currently engineering method being explored, including (1) structural engineering, (2) compositional engineering, (3) functional engineering, and (4) performance engineering. Also, the relationship between the engineering method and phototherapy performance was discussed in this review. In addition, the further development of Cu2-x S based phototherapy is prospected, including smart materials based phototherapy, phototherapy induced immune microenvironment modulation et al. This review will provide new ideas and opportunities for engineering of Cu2-x S with better phototherapy performance. This article is categorized under: Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Cobre/química , Cobre/farmacologia , Fototerapia/métodos , Sulfetos/química , Sulfetos/farmacologia , Neoplasias/terapia , Nanopartículas/química , Microambiente Tumoral
6.
ACS Nano ; 17(21): 21153-21169, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37921421

RESUMO

Innate and adaptive immunity is important for initiating and maintaining immune function. The nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome serves as a checkpoint in innate and adaptive immunity, promoting the secretion of pro-inflammatory cytokines and gasdermin D-mediated pyroptosis. As a highly inflammatory form of cell death distinct from apoptosis, pyroptosis can trigger immunogenic cell death and promote systemic immune responses in solid tumors. Previous studies proposed that NLRP3 was activated by translocation to the mitochondria. However, a recent authoritative study has challenged this model and proved that the Golgi apparatus might be a prerequisite for the activation of NLRP3. In this study, we first developed a Golgi apparatus-targeted photodynamic strategy to induce the activation of NLRP3 by precisely locating organelles. We found that Golgi apparatus-targeted photodynamic therapy could significantly upregulate NLRP3 expression to promote the subsequent release of intracellular proinflammatory contents such as IL-1ß or IL-18, creating an inflammatory storm to enhance innate immunity. Moreover, this acute NLRP3 upregulation also activated its downstream classical caspase-1-dependent pyroptosis to enhance tumor immunogenicity, triggering adaptive immunity. Pyroptosis eventually led to immunogenic cell death, promoted the maturation of dendritic cells, and effectively activated antitumor immunity and long-lived immune memory. Overall, this Golgi apparatus-targeted strategy provided molecular insights into the occurrence of immunogenic pyroptosis and offered a platform to remodel the tumor microenvironment.


Assuntos
Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Inflamassomos/metabolismo , Imunidade Inata , Complexo de Golgi/metabolismo , Interleucina-1beta , Caspase 1/metabolismo
7.
Nano Lett ; 23(21): 9851-9857, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37871176

RESUMO

Constructing two-dimensional (2D) artificial superlattices based on single-atom and few-atom nanoclusters is of great interest for exploring exotic physics. Here we report the realization of two types of artificial germanium (Ge) superlattice self-confined by a 37×37 R25.3° superstructure of bismuth (Bi) induced electronic kagome lattice potential valleys. Scanning tunneling microscopy measurements demonstrate that Ge atoms prefer to be confined in the center of the Bi electronic kagome lattice, forming a single-atom superlattice at 120 K. In contrast, room temperature grown Ge atoms and clusters are confined in the sharing triangle corner and the center, respectively, of the kagome lattice potential valleys, forming an artificial honeycomb superlattice. First-principle calculations and Mulliken population analysis corroborate that our reported atomically thin Bi superstructure on Au(111) has a kagome surface potential valley with the center of the inner Bi hexagon and the space between the outer Bi hexagons being energetically favorable for trapping Ge atoms.

8.
Acta Biomater ; 168: 606-616, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37479157

RESUMO

The misdiagnosis of tumors due to insufficient penetration depth or signal interference and damage to normal tissues due to indiscriminate treatment are the biggest challenges in using photothermal agents for clinical translation. To overcome these limitations, a strategy of switching from the near-infrared (NIR)-I region to the NIR-II region was developed based on tumor microenvironment (TME)-mediated gold (Au) self-assembly. Using zeolitic imidazolate framework-8 (ZIF-8) metal-organic framework-coated gold nanorods (AuNRs@ZIF-8) as a model photothermal agent, we demonstrated that only a NIR-I photoacoustic imaging signal was observed in normal tissue because ZIF-8 could prevent the aggregation of AuNRs. However, when ZIF-8 dissociated in the TME, the AuNRs aggregated to activate NIR-II photoacoustic imaging and attenuate the NIR-I signal, thereby allowing an accurate diagnosis of tumors based on signal transformation. Notably, TME-activated NIR-II photothermal therapy could also inhibit tumor growth. Therefore, this TME-activated NIR-I-to-NIR-II switching strategy could improve the accuracy of deep-tumor diagnoses and avoid the injury caused by undifferentiated treatment. STATEMENT OF SIGNIFICANCE: Photothermal agents used for photoacoustic imaging and photothermal therapy have garnered great attention for tumor theranostics. However, always "turned on" near-infrared (NIR)-I laser (700-1000 nm)-responsive photothermal agents face issues of penetration depth and damage to normal tissues. In contrast, tumor microenvironment-activated NIR-II "smart" photothermal agents exhibit deeper penetration depth and tumor selectivity. Therefore, a NIR-I-to-NIR-II switching strategy was developed based on tumor microenvironment-mediated Au self-assembly. This work provides a new strategy for developing tumor microenvironment-activated NIR-II smart photothermal agents.


Assuntos
Nanopartículas , Neoplasias , Humanos , Medicina de Precisão , Microambiente Tumoral , Neoplasias/patologia , Luz , Ouro/farmacologia , Ouro/uso terapêutico , Linhagem Celular Tumoral , Nanopartículas/uso terapêutico , Fototerapia/métodos , Nanomedicina Teranóstica/métodos
9.
Nanomedicine ; 50: 102668, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36933757

RESUMO

Frequency upconversion optical imaging has attracted great attention due to its remarkable advantages over traditional down-conversion optical imaging. However, the development of frequency upconversion optical imaging is extremely limited. Herein, five derivatives with BODIPY structure (B1-B5) were developed to investigate its frequency upconversion luminescence (FUCL) performance by introducing electron-donating and electron-withdrawing groups. Except for the nitro group decorated derivative, the other derivatives have strong and stable FUCL around 520 nm under 635 nm light excitation. More importantly, B5 retains FUCL ability after self-assembly. When applied to FUCL imaging of cells, B5 nanoparticles can be enriched in the cytoplasm and show a good signal-to-noise ratio. Meanwhile, FUCL tumor imaging can be achieved after 1 h of injection. This study not only provides a potential agent for FUCL biomedical imaging but also develops a new strategy for designing FUCL agents that exhibit excellent performance.


Assuntos
Nanopartículas , Neoplasias , Humanos , Luminescência , Nanopartículas/química
10.
ACS Appl Mater Interfaces ; 15(8): 10520-10528, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36794860

RESUMO

The long-standing misuse of antibiotics has accelerated the emergence of drug-resistant bacteria, which gives rise to an urgent public health threat. Antibacterial photodynamic therapy (aPDT), as a burgeoning and promising antibacterial strategy, plays an essential role in avoiding the evolution of drug-resistant microbes. However, it is hard for conventional photosensitizers to achieve satisfactory antibacterial efficacy because of the complex bacterial infectious microenvironment (BIME). Herein, a cascade BIME-triggered near-infrared cyanine (HA-CY) nanoplatform has been developed via conjugating cyanine units to biocompatible hyaluronic acid (HA) for enhanced aPDT efficacy. The HA-CY nanoparticles can be dissociated under the overexpressed hyaluronidase in BIME to release a cyanine photosensitizer. Meanwhile, cyanine can be protonated under acidic BIME, where protonated cyanine can efficiently adhere to the surface of a negatively charged bacterial membrane and increase singlet oxygen production due to intramolecular charge transfer (ICT). Experiments in the cellular level and animal model proved that the BIME-triggered activation of aPDT could remarkably boost aPDT efficacy. Overall, this BIME-triggered HA-CY nanoplatform presents great promise for overcoming the dilemma of drug-resistant microbes.


Assuntos
Infecções Bacterianas , Nanopartículas , Fotoquimioterapia , Animais , Fármacos Fotossensibilizantes/uso terapêutico , Antibacterianos , Corantes , Infecções Bacterianas/tratamento farmacológico
11.
J Colloid Interface Sci ; 629(Pt A): 554-562, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36088700

RESUMO

Magnetothermal therapy (MHT) has attracted significant attention due to the advantages of non-/minimal invasiveness, high efficiency, and excellent tissue penetration. However, developing small MHT agents (<50 nm) with excellent magnetothermal conversion performance and high tumor enrichment is a great challenge. Herein, a macrophage-mediated delivery of small Fe@Fe3O4-DHCA nanoparticles (∼14 nm) was designed for enhanced magnetic resonance imaging (MRI) and MHT of solid tumors. Based on the "Trojan horse" loading properties of the macrophages (RAW267.4 cells), the aggregation of Fe@Fe3O4-DHCA nanoparticles in the cells results in an enhanced MRI and magnetothermal performance in vitro. In addition, the MHT effect of RAW267.4 loaded with Fe@Fe3O4-DHCA in vivo is better than that of Fe@Fe3O4-DHCA alone, due to the tumor-targeting performance of RAW267.4 cells. This macrophage-mediated delivery provides a new strategy for the enhanced treatment effect of MHT based on Fe@Fe3O4-DHCA nanoparticles, and has great application potential for clinic tumor therapy.


Assuntos
Nanopartículas de Magnetita , Nanopartículas , Linhagem Celular Tumoral , Magnetismo , Imageamento por Ressonância Magnética/métodos , Macrófagos
12.
Eur J Nucl Med Mol Imaging ; 50(2): 275-286, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36242616

RESUMO

Radionuclides theranostic are ideal "partners" for bispecific antibodies to explore the immune response of patients and synergistic treatment. A bispecific single-domain antibody-Fc fusion protein, KN046, exhibits a good treatment effect by binding to programmed cell death-ligand 1 (PD-L1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4). An ionizing-radiation stimulus mediated by a low-dose of [131I] may be used for immunopotentiation. In this study, we established [131I]-labeled KN046 as a novel radioimmunotherapy agent to treat malignant melanoma and explored the mechanism. METHODS: After intravenous injection of [131I]-KN046, SPECT/CT imaging was applied to identify candidate targets for KN046 immunotherapy. [18F]-FDG and [68 Ga]-NOTA-GZP (granzyme B-specific PET imaging agent) micro-PET/CT imaging was used to assess the immune response in vivo after [131I]-KN046 treatment. The synergistic treatment effect of [131I]-KN046 was evaluated by exploring the [131I]-based radionuclide-induced release of tumor immunogenicity-related antigens as well as the histology and survival of tumor-bearing mice after treatment. RESULTS: The constructed [131I]-KN046 exhibited high affinity and specificity for PD-L1/CTLA-4 immune targets and had excellent in vivo intratumoral retention capability so as to achieve good antitumor efficacy. More importantly, the combination of low-dose [131I] and KN046-enhanced immunosensitivity increased the immunotherapy response rates significantly. Exposure of tumor cells to [131I]-KN046 led to upregulated expression of MHC-I and Fas surface molecules and significant increases in the degree of T-cell activation and counts of tumor-infiltrating immunocytes. CONCLUSION: Use of low-dose [131I] combined with a dual-target immunosuppressant could be exploited to identify the subset of treatment responders but also exhibited great potential for enhancing antitumor immune responses.


Assuntos
Antineoplásicos , Melanoma , Animais , Camundongos , Antígeno CTLA-4 , Imunossupressores , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Antígeno B7-H1/metabolismo , Antineoplásicos/farmacologia , Radioisótopos do Iodo/uso terapêutico , Imunoterapia/métodos , Imunidade
13.
J Adv Res ; 41: 159-168, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36328745

RESUMO

INTRODUCTION: Photothermal therapy can be synergistically combined with chemotherapy to improve the therapeutic effect for colon cancer. However, conventional therapeutic agents have side effects in normal tissues, limiting their application. OBJECTIVES: To reduce these side effects, a smart agent (Cur@HKUST-1@PVP) whose functionality is triggered by the high content of endogenous hydrogen sulfide in colon tumors was engineered for photoacoustic imaging-guided combination of photothermal therapy and chemotherapy for colon tumors. METHODS: After reacting with hydrogen sulfide, Cur@HKUST-1@PVP simultaneously generates CuS and releases curcumin. The generated CuS serves as an imaging agent for both photothermal therapy and photoacoustic imaging, while the released curcumin is used for chemotherapy. RESULTS: In vivo photoacoustic imaging experiments demonstrated that Cur@HKUST-1@PVP can be used for selectively imaging colon cancer tumors. In vivo experiments in mice for treatment suggested that the endogenous hydrogen sulfide-activated combination of photothermal therapy and chemotherapy has a better treatment effect that photothermal therapy or chemotherapy treatment alone. CONCLUSION: The endogenous hydrogen sulfide-activated Cur@HKUST-1@PVP agent developed herein shows great potential for the accurate diagnosis and effective treatment of colon cancer.


Assuntos
Neoplasias do Colo , Curcumina , Sulfeto de Hidrogênio , Técnicas Fotoacústicas , Camundongos , Animais , Técnicas Fotoacústicas/métodos , Terapia Fototérmica , Curcumina/uso terapêutico , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/tratamento farmacológico
14.
ACS Appl Mater Interfaces ; 14(34): 38604-38616, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35979620

RESUMO

Chemodynamic therapy (CDT) is a highly tumor-specific and minimally invasive treatment that is widely used in cancer therapy. However, its therapeutic effect is limited by the poor efficiency of hydroxyl radical generation. In colon cancer in particular, the high expression of hydrogen sulfide (H2S), which has strong reducibility, results in the consumption of generated hydroxyl radicals, further weakening the efficacy of CDT. To overcome this problem, we developed a novel two-dimensional (2D) Cu-bipyridine metal-organic framework (MOF) nanosheet [Cu(bpy)2(OTf)2] for colon cancer CDT. The therapeutic effect of Cu(bpy)2(OTf)2 is enhanced based on three factors. First, the developed 2D Cu-MOF rapidly consumes H2S to inhibit the consumption of generated hydroxyl radicals. Second, the ultrasmall CuS generated after H2S depletion facilitates Fenton-like reactions. Third, the generated CuS exhibits good photothermal performance in the second near-infrared window, allowing for photothermal-enhanced CDT. The ability of Cu(bpy)2(OTf)2 to improve the CDT effect was demonstrated through both in vitro and in vivo experiments. This work demonstrates the applicability of 2D Cu-MOF in the CDT of colon cancer and provides a novel strategy for constructing CDT agents for colon cancer.


Assuntos
Neoplasias do Colo , Hipertermia Induzida , Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Humanos , Peróxido de Hidrogênio/metabolismo , Radical Hidroxila/metabolismo , Hipertermia Induzida/métodos , Estruturas Metalorgânicas/farmacologia , Estruturas Metalorgânicas/uso terapêutico , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Fototerapia/métodos
15.
J Nanobiotechnology ; 20(1): 346, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35883134

RESUMO

BACKGROUND: Endogenous hydrogen sulfide (H2S)-responsive theranostic agents have attracted extensive attention due to their specificity for colon cancer. However, the development of such agents with high enrichment in tumors and excellent photothermal performance remains challenging. RESULTS: We prepared hyaluronic acid (HA)-coated Bi-doped cuprous oxide (Bi:Cu2O@HA) via a one-pot method. The HA specifically targets colon cancer tumor cells to improve the enrichment of Bi:Cu2O@HA at tumor sites, while the doped Bi both enhances the photothermal performance of the H2S-triggered Cu2O and serves as an agent for tumor imaging. The results in this work demonstrated that the Bi:Cu2O@HA nanoparticles exhibit good biocompatibility, target colon cancer tumor cells, facilitate computed tomography imaging, and enhanced H2S-responsive photothermal therapy performance, resulting in an excellent therapeutic effect in colon cancer. CONCLUSIONS: The novel Bi:Cu2O@HA nanoparticles exhibit excellent tumor targeting and photothermal therapeutic effects, which provide new strategies and insights for colon cancer therapy.


Assuntos
Neoplasias do Colo , Nanopartículas , Linhagem Celular Tumoral , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/tratamento farmacológico , Humanos , Ácido Hialurônico , Fototerapia
16.
ACS Appl Mater Interfaces ; 14(28): 32738-32746, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35802412

RESUMO

Monolayer PbSe has been predicted to be a two-dimensional (2D) topological crystalline insulator (TCI) with crystalline symmetry-protected Dirac-cone-like edge states. Recently, few-layered epitaxial PbSe has been grown on the SrTiO3 substrate successfully, but the corresponding signature of the TCI was only observed for films not thinner than seven monolayers, largely due to interfacial strain. Here, we demonstrate a two-step method based on molecular beam epitaxy for the growth of the PbSe-CuSe lateral heterostructure on the Cu(111) substrate, in which we observe a nanopore-patterned CuSe layer that acts as the template for lateral epitaxial growth of PbSe. This further results in a PbSe-CuSe lateral heterostructure with an atomically sharp interface. Scanning tunneling microscopy and spectroscopy measurements reveal a fourfold symmetric square lattice of such PbSe with a quasi-particle band gap of 1.8 eV, a value highly comparable with the theoretical value of freestanding PbSe. The weak monolayer-substrate interaction is further supported by both density functional theory (DFT) and projected crystal orbital Hamilton population, with the former predicting the monolayer's anti-bond state to reside below the Fermi level. Our work demonstrates a practical strategy to fabricate a high-quality in-plane heterostructure, involving a monolayer TCI, which is viable for further exploration of the topology-derived quantum physics and phenomena in the monolayer limit.

17.
Adv Sci (Weinh) ; 8(20): e2102500, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34473430

RESUMO

Combinations of immune checkpoint therapies show encouraging results in the treatment of many human cancers. However, the higher costs and greater side effects of such combinations compared with single-agent immunotherapies limit their further applications. In this work, a novel smart agent, KN046@19 F-ZIF-8, is developed to overcome these limitations. KN046 is a novel recombinant humanized PD-L1/CTLA-4 bispecific single-domain antibody-Fc fusion protein, which can bind to both PD-L1 and CTLA-4 effectively. ZIF-8 is a smart delivery system, which can safely and effectively deliver KN406 to a tumor. In vitro and in vivo results demonstrate that the smart agent KN046@19 F-ZIF-8 not only improves the immune response rate of the antibody drug in treatment of tumors but also reduces its toxic side effects, thereby achieving excellent antitumor efficacy. This study provides an engineering strategy for clinical applications of a more effective immunotherapy.


Assuntos
Anticorpos Biespecíficos , Antígeno B7-H1 , Antígeno CTLA-4 , Neoplasias , Animais , Humanos , Camundongos , Anticorpos Biespecíficos/química , Anticorpos Biespecíficos/imunologia , Anticorpos Biespecíficos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/genética , Antígeno CTLA-4/imunologia , Inibidores de Checkpoint Imunológico/farmacologia , Imunoterapia , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/terapia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/farmacologia , Anticorpos de Domínio Único/química , Anticorpos de Domínio Único/imunologia , Anticorpos de Domínio Único/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Sci Rep ; 11(1): 3414, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33564022

RESUMO

Intensive efforts have been devoted to surface Ullmann-like coupling in recent years, due to its appealing success towards on-surface synthesis of tailor-made nanostructures. While attentions were mostly drawn on metallic substrates, however, Ullmann dehalogenation and coupling reaction on semimetal surfaces has been seldom addressed. Herein, we demonstrate the self-assembly of 2, 7-dibromopyrene (Br2Py) and the well controllable dehalogenation reaction of Br2Py on the Bi(111)-Ag substrate with a combination of scanning tunnelling microscopy (STM) and density functional theory calculations (DFT). By elaborately investigating the reaction path and formed organic nanostructures, it is revealed that the pristinely inert bismuth layer supported on the silver substrate can initiate Ullmann-like coupling in a desired manner by getting alloyed with Ag atoms underneath, while side products have not been discovered. By clarifying the pristine nature of Bi-Ag(111) and Ullmann-like reaction mechanisms, our report proposes an ideal template for thoroughly exploring dehalogenative coupling reaction mechanisms with atomic insights and on-surface synthesis of carbon-based architectures.

19.
Nanomedicine ; 32: 102335, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33220508

RESUMO

Targeted T1-T2 MRI contrast agents, which can eliminate the difficulty of image matching across multiple imaging instruments and permit specific localization of lesions, are promising candidates for more accurate diagnosis of tumors. In this study, ultrasmall Fe@Fe3O4 nanoparticles were designed and synthesized as T1-T2 dual-mode MRI contrast agents for accurate tumor imaging. First, to investigate the influence of nanoparticle size, Fe@Fe3O4 nanoparticles with diameters of 4, 8, and 12 nm were prepared, among which the 8 nm 3-(3,4-dihydroxyphenyl)propionic acid (DHCA)-modified nanoparticles exhibited the optimal T1-T2 dual-mode MRI performance. Next, to develop a tumor-targeted contrast agent, the DHCA-Fe@Fe3O4 nanoparticles were conjugated with the F56 peptide, which targets the vascular endothelial growth factor receptor, and the resulting F56-DHCA-Fe@Fe3O4 nanoparticles were found to exhibit good T1-T2 dual-mode imaging and tumor-targeting performance both in vitro and in vivo, indicating the nanoparticles represent a new research tool for accurate tumor diagnosis.


Assuntos
Meios de Contraste/química , Diagnóstico por Imagem , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/química , Neoplasias/diagnóstico por imagem , Tamanho da Partícula , Resinas Acrílicas/química , Ácidos Cafeicos/química , Células HCT116 , Células Endoteliais da Veia Umbilical Humana , Humanos , Nanopartículas de Magnetita/ultraestrutura , Polietilenoglicóis/química , Solubilidade
20.
ACS Appl Bio Mater ; 4(7): 5753-5764, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35006738

RESUMO

Although multimethod therapy has shown great promise for effective cancer treatment, it is still a great challenge to develop simple and effective strategies to construct multifunctional therapeutic reagents. According to the characteristics of the tumor microenvironment, such as a mild acidic environment and overexpression of H2O2, an intelligent therapeutic reagent with photoacoustic (PA) imaging-guided photothermal therapy, chemodynamic therapy, and in situ chemotherapy was constructed by simply loading disulfiram (DSF) in a Cu-based porous metal-organic framework (HKUST-1). The resultant material DFS@HKUST-1 shows near-infrared adsorption around 600-900 nm and effective photoacoustic imaging properties and photothermal conversion efficiency upon 808 nm irradiation. Besides, after DFS@HKUST-1 is enriched in the tumor, the acidic environment of the tumor will slowly trigger the decomposition of HKUST-1, leading to the release of Cu2+ ions to react with DSF and endogenous H2O2 to generate the Cu/DSF complex (CuET) and cytotoxic •OH for chemotherapy and chemodynamic therapy, respectively. Therefore, DFS@HKUST-1 can serve as a promising tumor microenvironment response therapeutic reagent for photoacoustic imaging-guided multimethod therapy.


Assuntos
Estruturas Metalorgânicas , Neoplasias , Técnicas Fotoacústicas , Cobre/uso terapêutico , Dissulfiram/farmacologia , Humanos , Peróxido de Hidrogênio/uso terapêutico , Indicadores e Reagentes/uso terapêutico , Estruturas Metalorgânicas/uso terapêutico , Neoplasias/diagnóstico por imagem , Microambiente Tumoral
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