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1.
Ultrasonics ; 142: 107402, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39013349

RESUMO

Bolted joints are widely used in various machines and engineering structures. The tightening state of bolts directly affects the reliability and safety of bolted joints. Therefore, the bolt looseness detection is very important to ensure the reliability of bolted joints. In this paper, a novel nonlinear ultrasonic wave mixing method is proposed for looseness detection of bolted joints. The basic theory of the nonlinear ultrasonic wave mixing method for detecting the bolt looseness is established. Based on the detection theory, a nonlinear modulation index is defined to quantify the level of bolt looseness. An experimental setup is built to implement the nonlinear ultrasonic wave mixing detection method on bolted joints. Experiments are conducted on two bolted joints with different materials and sizes. The influences of excitation frequencies and voltages of two ultrasonic signals on the detection performance are investigated experimentally. A method is proposed for the selection of appropriate excitation frequencies to improve the detection performance. The experimental results demonstrate that the proposed method can effectively detect bolt looseness and it has good detection sensitivity to the early bolt loosening.

2.
Phys Chem Chem Phys ; 26(24): 17223-17231, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38855975

RESUMO

The electronic, optical and photocatalytic properties of GaN/C2N van der Waals heterostructures are investigated using the first-principles theory, and effective regulation through element doping or strain is achieved further. The results show that the GaN/C2N heterostructure exhibits a type-II band alignment with an indirect band gap of 2.25 eV, which benefits photocatalytic water splitting. In this study, both type-I and type-II band alignments can be obtained through doping or strain modulation. Doping with P or As atoms reduces the band gap of the GaN/C2N heterostructure and transforms it to a type-I direct bandgap semiconductor, which makes the doped GaN/C2N heterostructure more suitable for optoelectronic devices. In addition, the GaN/C2N heterostructure retains type-II band alignment and has a decreased band gap under tensile strain (0 to +4%), which is more favorable for photocatalytic water splitting. Compressive strain (0 to -4%) converts the type-II band alignment to type-I, resulting in a wider light absorption range, making the GaN/C2N heterostructure more suitable for optoelectronic devices. These theoretical results are helpful for the design of GaN/C2N vdW heterostructures in the fields of optoelectronic devices and photocatalysts.

3.
Nano Today ; 542024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38681872

RESUMO

The prevailing desmoplastic stroma and immunosuppressive microenvironment within pancreatic ductal adenocarcinoma (PDAC) pose substantial challenges to therapeutic intervention. Despite the potential of protein tyrosine kinase (PTK) inhibitors in mitigating the desmoplastic stromal response and enhancing the immune milieu, their efficacy is curtailed by suboptimal pharmacokinetics (PK) and insufficient tumor penetration. To surmount these hurdles, we have pioneered a novel strategy, employing lipid bilayer-coated mesoporous silica nanoparticles (termed "silicasomes") as a carrier for the delivery of Nintedanib. Nintedanib, a triple PTK inhibitor that targets vascular endothelial growth factor, platelet-derived growth factor and fibroblast growth factor receptors, was encapsulated in the pores of silicasomes via a remote loading mechanism for weak bases. This innovative approach not only enhanced pharmacokinetics and intratumor drug concentrations but also orchestrated a transformative shift in the desmoplastic and immune landscape in a robust orthotopic KRAS-mediated pancreatic carcinoma (KPC) model. Our results demonstrate attenuation of vascular density and collagen content through encapsulated Nintedanib treatment, concomitant with significant augmentation of the CD8+/FoxP3+ T-cell ratio. This remodeling was notably correlated with tumor regression in the KPC model. Strikingly, the synergy between encapsulated Nintedanib and anti-PD-1 immunotherapy further potentiated the antitumor effect. Both free and encapsulated Nintedanib induced a transcriptional upregulation of PD-L1 via the extracellular signal-regulated kinase (ERK) pathway. In summary, our pioneering approach involving the silicasome carrier not only improved antitumor angiogenesis but also profoundly reshaped the desmoplastic stromal and immune landscape within PDAC. These insights hold excellent promise for the development of innovative combinatorial strategies in PDAC therapy.

5.
ACS Nano ; 17(5): 4942-4957, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36853930

RESUMO

While oral desensitization is capable of alleviating peanut allergen anaphylaxis, long-term immune tolerance is the sought-after goal. We developed a liver-targeting lipid nanoparticle (LNP) platform to deliver mRNA-encoded peanut allergen epitopes to liver sinusoidal endothelial cells (LSECs), which function as robust tolerogenic antigen-presenting cells that induce FoxP3+ regulatory T-cells (Tregs). The mRNA strand was constructed by including nucleotide sequences encoding for nonallergenic MHC-II binding T-cell epitopes, identified in the dominant peanut allergen, Ara h2. These epitopes were inserted in the mRNA strand downstream of an MHC-II targeting sequence, further endowed in vitro with 5' and 3' capping sequences, a PolyA tail, and uridine substitution. Codon-optimized mRNA was used for microfluidics synthesis of LNPs with an ionizable cationic lipid, also decorated with a lipid-anchored mannose ligand for LSEC targeting. Biodistribution to the liver was confirmed by in vivo imaging, while ELISpot assays demonstrated an increase in IL-10-producing Tregs in the spleen. Prophylactic administration of tandem-repeat or a combination of encapsulated Ara h2 epitopes induced robust tolerogenic effects in C3H/HeJ mice, sensitized to and subsequently challenged with crude peanut allergen extract. In addition to alleviating physical manifestations of anaphylaxis, there was suppression of Th2-mediated cytokine production, IgE synthesis, and mast cell release, accompanied by increased IL-10 and TGF-ß production in the peritoneum. Similar efficacy was demonstrated during LNP administration postsensitization. While nondecorated particles had lesser but significant effects, PolyA/LNP-Man lacked protective effects. These results demonstrate an exciting application of mRNA/LNP for treatment of food allergen anaphylaxis, with the promise to be widely applicable to the allergy field.


Assuntos
Anafilaxia , Camundongos , Animais , Anafilaxia/terapia , Interleucina-10 , Arachis , Epitopos , RNA Mensageiro/genética , Sequência de Bases , Células Endoteliais , Distribuição Tecidual , Imunoglobulina E , Camundongos Endogâmicos C3H , Fígado , Alérgenos , Lipídeos
6.
Graefes Arch Clin Exp Ophthalmol ; 261(7): 1811-1822, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36617582

RESUMO

PURPOSE: To apply propensity score matching to evaluate the impact of peripapillary staphylomas (PPS) on vascular and structural characteristics in the myopic eyes. METHODS: This was a prospective, cross-sectional study. Forty-one control eyes and 41 eyes with PPS were analyzed. The eyes were selected using propensity score matching analysis based on the age and axial length. All subjects underwent ophthalmologic examinations for assessing vessel and structure parameters using swept-source optical coherence tomography (SS-OCT), OCT angiography, color fundus photography, and ocular biometry. RESULTS: As compared with control eyes, the eyes with PPS had shallower anterior chamber depth (3.61 ± 0.24 mm vs 3.77 ± 0.24 mm, P = 0.004), higher intraocular pressure (IOP) (16.59 ± 2.88 mmHg vs 14.53 ± 2.45 mmHg, P = 0.002), and higher myopic spherical equivalent (- 11.52 ± 3.22D vs - 9.88 ± 2.20D, P = 0.009). while corneal curvature and lens thickness between the two groups were not statistically different. Compared with control eyes, increased macular deep vessel density, reduced macular choriocapillaris and radial peripapillary capillary, and thinning retinal layer, ganglion cell complex, choroidal layer as well as the superior and inferior peripapillary retinal nerve fiber layer were observed in eyes with PPS, apart from larger disc area, parapapillary atrophy area, and degree of disc rotation. Logistic regression analysis revealed that the IOP (P = 0.046), disc rotation (P = 0.003), and average peripapillary choroidal thickness (P = 0.009) were associated with the presence of PPS. CONCLUSION: Close association of PPS with exacerbation of myopia and anatomical alterations was observed which not only affected the eye posterior segment but also the anterior segments. We further identified significant reductions in the radial peripapillary capillary and macular choroidal perfusion with the increase in macular deep retinal flow blood of myopic eyes with PPS. Higher IOP, thinner peripapillary choroidal thickness, and rotated optic disc were risk factors for the presence of PPS.


Assuntos
Miopia , Disco Óptico , Humanos , Estudos Transversais , Estudos Prospectivos , Pontuação de Propensão , Miopia/complicações , Miopia/diagnóstico , Disco Óptico/irrigação sanguínea , Tomografia de Coerência Óptica/métodos
7.
Regen Biomater ; 9: rbac036, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35936552

RESUMO

The recently emerging bismuth oxyhalide (BiOX) nanomaterials are promising indirect band gap photosensitizer for ultraviolet (UV) light-triggered phototherapy due to their unique layered nanosheet structure. However, the low absorption and poor photothermal conversion efficiency have always impeded their further applications in cancer clinical therapy. Herein, BiOCl rich in oxygen vacancies has been reported to have full-spectrum absorption properties, making it possible to achieve photothermal property under near-infrared laser. Under 808 nm irradiation, the photothermal conversion efficiency of black BiOCl nanosheets (BBNs) is up to 40%. BBNs@PEG can effectively clear primary subcutaneous tumors and prevent recurrence, achieving good synergistic treatment effect. These results not only broke the limitation of UV on the BiOCl material and provided a good template for other semiconductor materials, but also represent a promising approach to fabricate BBN@PEG a novel, potent and multifunctional theranostic platform for precise photothermal therapy and prognostic evaluation.

8.
ACS Nano ; 16(8): 13168-13182, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35920660

RESUMO

Although toll-like receptor (TLR) agonists hold great promise as immune modulators for reprogramming the suppressive immune landscape in pancreatic ductal adenocarcinoma (PDAC), their use is limited by poor pharmacokinetics (PK) and off-target systemic inflammatory effects. To overcome these challenges as well as to attain drug synergy, we developed a lipid bilayer (LB)-coated mesoporous silica nanoparticle (silicasome) platform for co-delivery of the TLR7/8 agonist 3M-052 with the immunogenic chemotherapeutic agent irinotecan. This was accomplished by incorporating the C18 lipid tail of 3M-052 in the coated LB, also useful for irinotecan remote loading in the porous interior. Not only did the co-formulated carrier improve PK, but it strengthened the irinotecan-induced immunogenic cell death response by 3M-052-mediated dendritic cell activation at the tumor site as well as participating lymph nodes. The accompanying increase in CD8+ T-cell infiltration along with a reduced number of regulatory T-cells was associated with tumor shrinkage and metastasis disappearance in subcutaneous and orthotopic KRAS-mediated pancreatic carcinoma tumor models. Moreover, this therapeutic outcome was accomplished without drug or nanocarrier toxicity. All considered, dual-delivery strategies that combine chemo-immunotherapy with co-formulated TLR agonists or other lipid-soluble immune modulators predict successful intervention in heterogeneous PDAC immune landscapes.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Irinotecano/uso terapêutico , Receptor 7 Toll-Like/agonistas , Morte Celular Imunogênica , Linhagem Celular Tumoral , Neoplasias Pancreáticas/tratamento farmacológico , Imunoterapia , Carcinoma Ductal Pancreático/tratamento farmacológico , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/uso terapêutico , Bicamadas Lipídicas , Neoplasias Pancreáticas
10.
Vet Microbiol ; 258: 109126, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34020176

RESUMO

Mycobacterium bovis (M. bovis) infection triggers cytokine production via pattern recognition receptors. These cytokines include type I interferons (IFNs) and interleukin-1ß (IL-1ß). Excessive type I IFN levels impair host resistance to M. bovis infection. Therefore, strict control of type I IFN production is helpful to reduce pathological damage and bacterial burden. Here, we found that a deficiency in caspase-1, which is the critical component of the inflammasome responsible for IL-1ß production, resulted in increased IFN-ß production upon M. bovis infection. Subsequent experiments demonstrated that caspase-1 activation reduced cyclic GMP-AMP synthase (cGAS) expression, thereby inhibiting downstream TANK-binding kinase 1 (TBK1)- interferon regulatory factor 3 (IRF3) signaling and ultimately reducing IFN production. A deficiency in caspase-1 activation enhanced the bacterial burden during M. bovis infection in vitro and in vivo and aggravated pathological lesion formation. Thus, caspase-1 activation reduced IFN-ß production upon M. bovis infection by dampening cGAS-TBK1-IRF3 signaling, suggesting that the inflammasome protects hosts by negatively regulating harmful cytokines.


Assuntos
Caspase 1/metabolismo , Animais , Inibidores de Caspase/farmacologia , Sobrevivência Celular , Dipeptídeos/farmacologia , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Inflamassomos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Interferon beta , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium bovis , Nucleotidiltransferases , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Distribuição Aleatória , para-Aminobenzoatos/farmacologia
11.
Graefes Arch Clin Exp Ophthalmol ; 259(8): 2119-2130, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33404680

RESUMO

OBJECTIVE: To investigate the microvasculature and structural characteristics of the eyes of myopic patients and their association with posterior staphyloma (PS). METHODS: This was a retrospective, case-control study comprising of 106 eyes from 72 individuals. Using 1:1 matching of axial length (AL) of their eyes, patients were allocated into a PS group or no posterior staphyloma (NPS) group. All patients were examined using ultra-widefield fundus imaging, optical coherence tomography angiography, and ocular biometry to acquire microvasculature and microstructure parameters. RESULTS: The anterior chamber depth (ACD) of the PS group was significantly different from that of the NPS group (3.56 mm vs 3.76 mm, P < 0.001), as was 1ens thickness (3.72 mm vs 3.57 mm, P = 0.005) and spherical equivalent (SE)(-10.11D vs -8.80D, P = 0.014). The PS group had reduced choriocapillaris flow, subfoveal choroidal thickness (SFCT), and a thinner retinal layer compared with the NPS group. No difference in retinal blood flow between the two groups was observed. The PS group exhibited a smaller disc area (15082.89 vs 17,043.32, P = 0.003) and angle α between temporal retinal arterial vascular arcades (113.29°vs 128.39°, P = 0.003), a larger disc tilt ratio (1.41 vs 1.24, P < 0.001) and parapapillary atrophy (PPA) area (13840.98 vs 8753.86, P = 0.020), compared with the NPS group. Multivariate regression analysis indicated that disc tilt ratio (P = 0.031) and SFCT (P = 0.015) were significant predictors of PS. In addition, PS (P = 0.049), AL (P = 0.003), corneal refractive power (P < 0.001), ACD (P = 0.022), relative lens position (P = 0.045), and disc area (P = 0.011) were significant predictors of SE. CONCLUSIONS: PS was found to be closely linked to a reduction in choriocapillaris perfusion and anatomical abnormalities including posterior and anterior segments. Furthermore, PS exacerbated the progression of myopia.


Assuntos
Miopia , Doenças da Esclera , Estudos de Casos e Controles , Humanos , Microvasos , Miopia/diagnóstico , Estudos Retrospectivos , Doenças da Esclera/diagnóstico , Tomografia de Coerência Óptica
12.
Artigo em Inglês | MEDLINE | ID: mdl-33102244

RESUMO

Background: Many studies have explored changes in the gut microbiome associated with HIV infection, but the consistent pattern of changes has not been clarified. Men who have sex with men (MSM) are very likely to be an independent influencing factor of the gut microbiome, but relevant research is still lacking. Methods: We conducted a meta-analysis by screening 12 published studies of 16S rRNA gene amplicon sequencing of gut microbiomes related to HIV/AIDS (six of these studies contain data that is relevant and available to MSM) from NCBI and EBI databases. The analysis of gut microbiomes related to HIV infection status and MSM status included 1,288 samples (HIV-positive (HIV+) individuals, n = 744; HIV-negative (HIV-) individuals, n = 544) and 632 samples (MSM, n = 328; non-MSM, n = 304), respectively. The alpha diversity indexes, beta diversity indexes, differentially enriched genera, differentially enriched species, and differentially enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) functional pathways related to gut microbiomes were calculated. Finally, the overall trend of the above indicators was evaluated. Results: Our results indicate that HIV+ status is associated with decreased alpha diversity of the gut microbiome. MSM status is an important factor that affects the study of HIV-related gut microbiomes; that is, MSM are associated with alpha diversity changes in the gut microbiome regardless of HIV infection, and the changes in the gut microbiome composition of MSM are more significant than those of HIV+ individuals. A consistent change in Bacteroides caccae, Bacteroides ovatus, Bacteroides uniformis, and Prevotella stercorea was found in HIV+ individuals and MSM. The differential expression of the gut microbiome may be accompanied by changes in functional pathways of carbohydrate metabolism, amino acid metabolism, and lipid Metabolism. Conclusions: This study shows that the changes in the gut microbiome are related to HIV and MSM status. Importantly, MSM status may have a far greater impact on the gut microbiome than HIV status.


Assuntos
Microbioma Gastrointestinal , Infecções por HIV , Minorias Sexuais e de Gênero , Bacteroides , Feminino , Infecções por HIV/complicações , Homossexualidade Masculina , Humanos , Masculino , Prevotella , RNA Ribossômico 16S/genética , Comportamento Sexual
13.
Biomed Res Int ; 2020: 1204605, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32566650

RESUMO

BACKGROUND: This study is aimed at identifying unknown clinically relevant genes involved in colorectal cancer using bioinformatics analysis. METHODS: Original microarray datasets GSE107499 (ulcerative colitis), GSE8671 (colorectal adenoma), and GSE32323 (colorectal cancer) were downloaded from the Gene Expression Omnibus. Common differentially expressed genes were filtered from the three datasets above. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed, followed by construction of a protein-protein interaction network to identify hub genes. Kaplan-Meier survival analysis and TIMER database analysis were used to screen the genes related to the prognosis and tumour-infiltrating immune cells of colorectal cancer. Receiver operating characteristic curves were used to assess whether the genes could be used as markers for the diagnosis of ulcerative colitis, colorectal adenoma, and colorectal cancer. RESULTS: A total of 237 differentially expressed genes common to the three datasets were identified, of which 60 were upregulated, 125 were downregulated, and 52 genes that were inconsistently up- and downregulated. Common differentially expressed genes were mainly enriched in the cellular component of extracellular exosome and integral component of membrane categories. Eight hub genes, i.e., CXCL3, CXCL8, CEACAM7, CNTN3, SLC1A1, SLC16A9, SLC4A4, and TIMP1, were related to the prognosis and tumour-infiltrating immune cells of colorectal cancer, and these genes have diagnostic value for ulcerative colitis, colorectal adenoma, and colorectal cancer. CONCLUSION: Three novel genes, CNTN3, SLC1A1, and SLC16A9 were shown to have diagnostic value with respect to the occurrence of colorectal cancer and should be verified in future studies.


Assuntos
Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/metabolismo , Contactinas , Transportador 3 de Aminoácido Excitatório , Transportadores de Ácidos Monocarboxílicos , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/genética , Biologia Computacional , Contactinas/análise , Contactinas/genética , Contactinas/metabolismo , Transportador 3 de Aminoácido Excitatório/análise , Transportador 3 de Aminoácido Excitatório/genética , Transportador 3 de Aminoácido Excitatório/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Transportadores de Ácidos Monocarboxílicos/análise , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Mapas de Interação de Proteínas , Curva ROC , Transcriptoma/genética
14.
J Mater Chem B ; 7(39): 5983-5991, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31532444

RESUMO

Drug-loaded nanoparticles can be specifically uptaken by tumor cells to realize active targeting due to the conjugated ligands or antibodies on their surface. However, some non-cancerous cells express non-specific receptors or antigens on their surface, which can react with the ligands or antibodies conjugated on the nanoparticle surface and then result in non-specific uptake of the nanoparticles by non-cancerous cells. In order to reduce the non-specific uptake of nanoparticles by non-cancerous cells, in this study, we proposed a pH-sensitive polymer based precise tumor targeting strategy and synthesized superparamagnetic iron oxide nanoparticle (SPION) encapsulated albumin nanoparticles (AN) with conjugation of folic acid (FA) and mPEG-DCA (SPION-AN-FA@mPEG), in which mPEG can shield FA, avoiding the non-specific recognition by normal cells under physiological conditions, and can be shed to expose FA in tumor microenvironments. The pH-sensitivity of mPEG-DCA was verified by HPLC characterization and 1H-NMR spectroscopy. The graft density and length of mPEG-DCA were optimized via the cellular uptake of SPION-AN-FA@mPEG measured by flow cytometry analysis. The r2 value and r2/r1 ratio of the optimized SPION-AN-FA@mPEG (i.e., SPION-AN-FA@mPEG4) are 168.6 mM-1 s-1 and 42.8, respectively, which are both much higher than that of the commercial contrast agent Resovist®. The in vitro T2-weighted MR images and in vivo MRI performance demonstrate that our SPION-AN-FA@mPEG4 nanoparticles can be used as an effective T2-weighted MRI contrast agent.


Assuntos
Terapia de Alvo Molecular , Nanopartículas/química , Nanopartículas/metabolismo , Polietilenoglicóis/química , Polietilenoglicóis/metabolismo , Transporte Biológico , Compostos Férricos/química , Receptor 1 de Folato/metabolismo , Ácido Fólico/química , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7
15.
Biomaterials ; 223: 119464, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31525691

RESUMO

Malignant melanoma, one of the most aggressive types of cancer easily metastasizes, making it extremely difficult to treat and unresponsive to current therapies. Recent breakthroughs in nanomaterials-based cancer immunotherapy have provided potential specific strategy for tumor and metastasis inhibition. With the development of nanotechnology, inorganic nanomaterials have been increasingly studied for their potential cancer therapeutic and molecular imaging functions. However, only iron-based nanomaterials have been approved by the Food and Drug Administration (FDA) in inorganic nanomedicines. For promising clinical application, a new type of nanocomposite is engineered by combining ultra-small iron oxide nanoparticles (Fe3O4 NPs) and ovalbumin (OVA), denoted as Fe3O4-OVA nanocomposites in this study. Interestingly, this is the first time that Fe3O4 NPs are found as nano-immunopotentiators helping nanocomposites efficiently stimulate dendritic cell-based immunotherapy and potentially-activate macrophages. These nanocomposites efficiently stimulate the maturation level of bone marrow derived dendritic cell (BMDCs) and corresponding activation of T cells and also potentially-activate macrophages. With the help of the Fe3O4 nano-immunopotentiators (Fe3O4 NPs), this therapeutic and prophylactic Fe3O4-OVA vaccine can not only efficiently inhibit the subcutaneous and metastatic B16-OVA tumor growth but also successfully prevent the formation of subcutaneous and metastatic tumor, providing a promising strategy for expanding the clinical use of Fe-based nanomaterials.


Assuntos
Compostos Férricos/química , Imunoterapia/métodos , Neoplasias Pulmonares/prevenção & controle , Melanoma/patologia , Neoplasias Cutâneas/terapia , Animais , Antígenos de Neoplasias/imunologia , Materiais Biocompatíveis/química , Células da Medula Óssea/citologia , Células Dendríticas/citologia , Feminino , Humanos , Neoplasias Pulmonares/secundário , Macrófagos/citologia , Melanoma/terapia , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Microscopia de Fluorescência , Nanomedicina/métodos , Metástase Neoplásica , Células RAW 264.7 , Neoplasias Cutâneas/patologia , Raios X
16.
Nano Lett ; 19(8): 5674-5682, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31361142

RESUMO

The efficiency of chemical intercommunication between enzymes in natural networks can be significantly enhanced by the organized catalytic cascades. Nevertheless, the exploration of two-or-more-enzymes-engineered nanoreactors for catalytic cascades remains a great challenge in cancer therapy because of the inherent drawbacks of natural enzymes. Here, encouraged by the catalytic activity of the individual nanozyme for benefiting the treatment of solid tumors, we propose an organized in situ catalytic cascades-enhanced synergistic therapeutic strategy driven by dual-nanozymes-engineered porphyrin metal-organic frameworks (PCN). Precisely, catalase-mimicking platinum nanoparticles (Pt NPs) were sandwiched by PCN, followed by embedding glucose oxidase-mimicking ultrasmall gold nanoparticles (Au NPs) within the outer shell, and further coordination with folic acid (P@Pt@P-Au-FA). The Pt NPs effectively enabled tumor hypoxia relief by catalyzing the intratumoral H2O2 to O2 for (1) enhancing the O2-dependent photodynamic therapy and (2) subsequently accelerating the depletion of ß-d-glucose by Au NPs for synergistic starving-like therapy with the self-produced H2O2 as the substrate for Pt NPs. Consequently, a remarkably strengthened antitumor efficiency with prevention of tumor recurrence and metastasis was achieved. This work highlights a rationally designed tumor microenvironment-specific nanoreactor for opening improved research in nanozymes and provides a means to design a catalytic cascade model for practical applications.


Assuntos
Ouro/uso terapêutico , Estruturas Metalorgânicas/uso terapêutico , Neoplasias/tratamento farmacológico , Platina/uso terapêutico , Porfirinas/uso terapêutico , Animais , Linhagem Celular Tumoral , Humanos , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/ultraestrutura , Camundongos , Neoplasias/patologia , Fotoquimioterapia
17.
Nanoscale ; 10(46): 22035-22043, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30452049

RESUMO

Currently, cancer immunotherapy appears to be an effective strategy for cancer therapy, but the state of unresponsiveness to tumor antigenic stimulation in immune systems is one of the stumbling blocks to the clinical applications of cancer immunotherapy. Nanomaterials have been increasingly applied in cancer immunotherapy by virtue of their irreplaceable superiority to carry antigens to specific sites and stimulate immune responses. Among the many excellent fluorescent nanomaterials, carbon dots (CDs) stand out from the others as a result of their extraordinary performance. Therefore, photoluminescent CDs were used as vaccine adjuvants to be combined with tumor protein antigen model ovalbumin (OVA), with red, yellow and green colored luminescence under different excitation wavelengths. These CDs could positively contribute to antigen uptake and efficiently accelerate the maturation of dendritic cells (DCs). The obtained nanocomposite of CDs and OVA (CDs-OVA) could efficiently enhance the expression of costimulatory molecules CD80 and CD86, and the production of tumor necrosis factor α (TNF-α) from DCs. In addition, CDs-OVA could also strongly stimulate splenocyte proliferation and the production of interferon gamma (IFN-γ). In addition, this CDs-OVA vaccine could effectively be endocytosed and processed by immune cells in vivo, then it could induce strong antigen-specific cellular immune responses to inhibit the growth of B16-OVA melanoma cancer in C57BL/6 mice. This work represents not only the first report of CDs as vaccine adjuvants for tumor inhibition, but also opens up many possibilities for more biomedical applications of CDs in cancer immunotherapy and in other potential clinical applications.


Assuntos
Adjuvantes Imunológicos/química , Carbono/química , Pontos Quânticos/química , Adjuvantes Imunológicos/uso terapêutico , Animais , Antígeno B7-2/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Dendríticas/citologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Feminino , Imunoterapia , Interferon gama/metabolismo , Melanoma Experimental/patologia , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Ovalbumina/química , Ovalbumina/imunologia , Baço/citologia , Baço/imunologia , Baço/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
18.
Small ; 14(35): e1801851, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30058139

RESUMO

AuroShell nanoparticles (sealed gold nanoshell on silica) are the only inorganic materials that are approved for clinical trial for photothermal ablation of solid tumors. Based on that, porous gold nanoshell structures are thus critical for cancer multiple theranostics in the future owing to their inherent cargo-loading ability. Nevertheless, adjusting the diverse experimental parameters of the reported procedures to obtain porous gold nanoshell structures is challenging. Herein, a series of amino-functionalized porous metal-organic frameworks (NH2 -MOFs) nanoparticles are uncovered as superior templates for porous gold nanoshell deposition (NH2 -MOFs@Aushell ) by means of a more facile and general one-step method, which combines the enriched functionalities of NH2 -MOFs with those of porous gold nanoshells. Moreover, in order to illustrate the promising applications of this method in biomedicine, platinum nanozymes-encapsulated NH2 -MOFs are further designed with porous gold nanoshell coating and photosensitizer chlorin e6 (Ce6)-loaded nanoparticles with continuous O2 -evolving ability (Pt@UiO-66-NH2 @Aushell -Ce6). The combination of photodynamic and photothermal therapy is then carried out both in vitro and in vivo, achieving excellent synergistic therapeutic outcomes. Therefore, this work not only presents a facile strategy to fabricate functionalized porous gold nanoshell structures, but also illustrates an excellent synergistic tumor therapy strategy.


Assuntos
Ouro/química , Estruturas Metalorgânicas/química , Nanoconchas/química , Neoplasias/terapia , Animais , Terapia Combinada , Humanos , Células MCF-7 , Estruturas Metalorgânicas/ultraestrutura , Camundongos , Nanoconchas/ultraestrutura , Porosidade , Temperatura
19.
Small ; 14(19): e1800094, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29655279

RESUMO

Gold nanoparticle (AuNP) assemblies (GNAs) have attracted attention since enhanced coupling plasmonic resonance (CPR) emerged in the nanogap between coupling AuNPs. For one dimensional GNAs (1D-GNAs), most CPR from the nanogaps could be easily activated by electromagnetic waves and generate drastically enhanced CPR because the nanogaps between coupling AuNPs are linearly distributed in the 1D-GNAs. The reported studies focus on the synthesis of 1D-GNAs and fundamental exploration of CPR. There are still problems which impede further applications in nanomedicine, such as big size (>500 nm), poor water solubility, and/or poor stability. In this study, a kind of 1D flexible caterpillar-like GNAs (CL-GNAs) with ultrasmall nanogaps, good water solubility, and good stability is developed. The CL-GNAs have a flexible structure that can randomly move to change their morphology, which is rarely reported. Numerous ultrasmall nanogaps (<1 nm) are linearly distributed along the structure of CL-GNAs and generate enhanced CPR. The toxicity assessments in vitro and vivo respectively demonstrate that CL-GNAs have a low cytotoxicity and good biocompatibility. The CL-GNAs can be used as an efficient photothermal agent for photothermal therapy, a probe for Raman imaging and photothermal imaging.


Assuntos
Diagnóstico por Imagem , Ouro/química , Hipertermia Induzida , Nanopartículas Metálicas/química , Fototerapia , Animais , Feminino , Humanos , Células MCF-7 , Nanopartículas Metálicas/ultraestrutura , Camundongos Nus , Soroalbumina Bovina/química , Análise Espectral Raman
20.
Nanoscale ; 10(13): 5845-5851, 2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29542782

RESUMO

Due to the molecular and cellular heterogeneity of glioma, discovery of novel targeted sites and ligands for glioma imaging and therapy remains challenging. Neuropeptide Y (NPY) Y1 receptors (Y1Rs) are highly over expressed in various brain tumors including glioma, and can serve as potential targeting sites for glioma imaging and therapy. Here, we show by in vivo fluorescent imaging that a highly selective Y1R ligand, [Asn6, Pro34] NPY (AP-NPY), facilitated circumvention of the blood brain barrier (BBB) by nanomicelles specifically targeting glioma. Modification with AP-NPY stabilized doxorubicin-loaded nanomicelles in the normal physiological state and promoted drug release in the acidic tumor microenvironment. Furthermore, targeted delivery of AP-NPY nanomicelles improved the therapeutic efficacy of doxorubicin for glioma, producing a prolonged survival rate. These results suggest that Y1R is a novel targeted receptor, and its selective ligand AP-NPY improves BBB permeability and glioma targeting. Our study paves the way for developing a novel delivery system for diagnosis and treatment of glioma in which Y1Rs are over expressed.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/tratamento farmacológico , Glioma/diagnóstico por imagem , Glioma/tratamento farmacológico , Nanopartículas , Receptores de Neuropeptídeo Y/metabolismo , Animais , Barreira Hematoencefálica , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Células Endoteliais , Humanos , Ligantes , Camundongos , Camundongos Nus , Micelas , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/tratamento farmacológico , Imagem Óptica , Ligação Proteica
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