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1.
Nanomaterials (Basel) ; 11(1)2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33450952

RESUMO

Two-phase flow with phase change in microstructure or nanostructure is an important issue in many fronts and critical applications nowadays, but with a lack of comprehensive understanding of the mechanism. This paper numerically investigates the transient behavior of two-phase flow with liquid phase change in the porous media, which consists of a series of connected pores at micro and nanoscale with the transient form of the semi-mixed model and self-compiled programs. Transient variation and spatial distribution of structure temperature, thermal non-equilibrium characteristic, phase change location and fluid-driven pressure are obtained and analyzed, and effects of initial system temperature, structure parameter and material property on the transient behaviors of two-phase flow and fluid-structure coupling heat transfer are discussed. The numerical simulations indicate that the two-phase flow with phase change in porous media is complex and ever-changing before reaching a steady state and affected by the above-mentioned three kinds of parameters significantly. Particularly, distinct phenomena of transient heat transfer deterioration and vapor block are discovered, and it is revealed that the transient heat transfer deterioration and vapor block are more serious in a porous matrix with smaller porosity and made of materials with higher heat capacity and density.

2.
World J Urol ; 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33475762

RESUMO

PURPOSE: To develop and validate a predictive nomogram for early stress urinary incontinence (SUI) after endoscopic enucleation of the prostate (EEP) in patients with benign prostatic hyperplasia (BPH). METHODS: The records of 458 patients who underwent plasmakinetic- or diode-based EEP at our center from March 2016 to December 2019 were reviewed. Among these, 326 and 132 cases were randomly assigned to the training and validation set, respectively. A predictive nomogram was constructed based on multivariate logistic regression analysis. Receiver operating characteristic (ROC) analysis and calibration curves were employed to evaluate its performance. RESULTS: 65 years ≤ age < 70 years, 75 years ≤ age, 25 kg/m2 ≤ BMI < 30 kg/m2, 30 kg/m2 ≤ BMI, 5 years ≤ LUTS duration, and 75 ml ≤ prostate volume were finally selected as independent predictors of early SUI into the multivariate logistics regression model. It was visualized as a concise nomogram with satisfactory discrimination and accuracy in both training and validation sets. CONCLUSIONS: A concise nomogram was developed and validated as a useful clinical tool for predicting early SUI post-EEP.

3.
Nanotechnology ; 32(8): 085505, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33142267

RESUMO

In the scanning probe microscope system, the weak signal detection of cantilever vibration is one of the important factors affecting the sensor sensitivity. In our current work, we present a novel design concept for an atomic force microscope (AFM) combined with optomechanics with an ultra-high quality factor and a low thermal noise. The detection system consists of a fixed mirror placed on the cantilever of the AFM and pump-probe beams that is equivalent to a Fabry-Perot cavity. We realize that the AFM combined with an optical cavity can achieve ultra-sensitive detection of force gradients of 10-12 N m-1 in the case of high-vacuum and low effective temperature of 1 mK, which may open up new avenues for super-high resolution imaging and super-high precision force spectroscopy.

4.
Biomaterials ; 264: 120453, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33069138

RESUMO

Thiol capped gold nanoparticles with small size, high dispersity, and broad light absorption covering ultraviolet (UV) to near infrared (NIR) region have been developed for catalysis, fluorescence imaging and photodynamic therapy (PDT). The constitution of the metal core in such nanoparticles can strongly influence the luminescence, catalysis, and stability properties. However, to date, a corresponding investigation of the influence of the metallic core on the generation of reaction oxygen species (ROS) and its therapeutic efficiency towards tumor cells remains to be lacking. Herein, we fabricated bimetallic nanoparticles by introducing bismuth into captopril capped gold nanoparticles. Surprisingly, the introduction of the Bi was found enhance the photothermal effect of the nanoparticles to a great extent, and the variation trends for the thermal effect, ROS generation rate, and tumor cell inhibition effect were found to disparate with the changes in the Au and Bi composition. The origin of the photothermal effect was deduced through density functional theory calculations based on microscopic construction. Combined with the intrinsic photodynamic effect, the bimetallic nanoparticles showed an outstanding tumor cell inhibition effect. Furthermore, due to the excellent CT imaging property, our designed nanoparticles provide the exciting possibility to realize CT imaging guided and light-mediated tumor therapy.

5.
Chemosphere ; 263: 128202, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297165

RESUMO

Pursuing a low-cost yet sustainable material with a high performance of removing boron is necessary for replacement of the synthetic adsorbents, but remains challengeable. Herein, we fabricated an mesopore-dominated bio-based material (LS-CPAM-TA) with abundant catechol groups by the electrostatic-interaction-driven self-assembly of lignosulfonate (LS), tannic acid (TA) and cationic polyacrylamide (CPAM) for efficient removal of boron. LS-CPAM-TA presented a mesopore area of 53.9 m2/g with a mesoporous distribution of 2-25 nm, as well as a mesopore/micropore volume ratio of 129.7. Such a mesopore-rich feature not only promoted the exposure of catechol groups in TA, which served as the adsorption sites, but also contributed to enhance the fast mass transport of boron. Consequently, a maximum adsorption capacity of 119.05 mg/g was observed for LS-CPAM-TA, surpassing some reported adsorbents. Even for the low concentration boron, LS-CPAM-TA also displayd the high adsorption efficiency. Moreover, LS-CPAM-TA followed the Langmuir isotherm adsorption model, and presented the excellent regeneration performance due to its robust self-assembled structure driven by the electrostatic interaction among LS, CPAM and TA. This work would provide guidelines for target design of bio-based materials with tunable porous structure and versatile adsorption or catalytic sites for various applications.


Assuntos
Boro , Taninos , Adsorção , Catecóis , Cátions
6.
Artigo em Inglês | MEDLINE | ID: mdl-33300776

RESUMO

Manipulating the strain effect of Ag without any foreign metals to boost its intrinsic oxygen reduction reaction (ORR) activity is intriguing, but it remains a challenge. Herein, we developed a class of Ag-based electrocatalysts with tunable strain structures for efficient ORR via ligand-assisted competitive decomposition of Ag-organic complexes (AgOCs). Benefiting from the superior coordination capability, 4,4'-bipyridine as a ligand triggered a stronger competition with NaBH4 for Ag ions during reduction-induced decomposition of AgOCs in comparison with the counterparts of the pyrazine ligand and the NO3- anion, which moderately modulated the compressive strain structure to upshift the d-band center of the catalyst and increase the electron density of Ag. Accordingly, the O2 adsorption was obviously improved, and the stronger repulsion effect between the Ag sites and the 4e ORR product, i.e., the electron-rich OH-, was generated to promote the desorption of OH- via the Ag-OH bond cleavage, which enabled more Ag sites to be regenerated after ORR. Both of these led to an enhancement to the intrinsic ORR activity of the Ag-based catalyst. This competitive decomposition of metal-organic complex strategy would provide a facile method to design other catalysts with the well-tuned strain structures for energy conversion and heterocatalysis.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33290033

RESUMO

Chemodynamic therapy (CDT) based on the Fenton reaction is a promising strategy for nonlight cancer treatment. However, the traditional Fenton reaction is only efficient in strongly acidic conditions (pH = 2-4), resulting in the limited curative effect in a weakly acidic tumor microenvironment (TME). Herein, we first developed a simple in situ growth method to confine FeOCl nanosheets into hollow dendritic mesoporous organosilicon (H-DMOS) nanoparticles to obtain FeOCl@H-DMOS nanospheres. Ascorbic acid (AA) was then absorbed on the nanosystem as a H2O2 prodrug and, meanwhile, was used for the regeneration of Fentons reagent for Fe2+. Finally, poly(ethylene glycol) (PEG) was coated on FeOCl@H-DMOS-AA to enhance the permeability and retention (EPR) effect in tumor tissue. The as-fabricated FeOCl@H-DMOS-AA/PEG can generate a large amount of highly toxic hydroxyl radicals (•OH) by catalyzing H2O2 even in neutral pH conditions with the help of AA. As a result, the effect of CDT has been markedly enhanced by the increased amount of H2O2 and the efficient Fenton reaction in mild acidic TME, which can remove almost all of the tumors in mice. In addition, FeOCl also endows the nanosystem with T2-weighted MR imaging capability (r2 = 34.08 mM-1 s-1), thus realizing the imaging-guided cancer therapy. All in all, our study may contribute a new direction and may have a bright future for enhanced CDT with a neutral pH range.

8.
Cancer Res ; 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33293426

RESUMO

The progression and metastatic capacity of solid tumors are strongly influenced by immune cells in the tumor microenvironment. In non-small cell lung cancer (NSCLC), accumulation of anti-inflammatory tumor-associated macrophages (TAMs) is associated with worse clinical outcome and resistance to therapy. Here we investigated the immune landscape of NSCLC in the presence of pro-tumoral TAMs expressing the macrophage receptor with collagenous structure (MARCO). MARCO-expressing TAM numbers correlated with increased occurrence of regulatory T cells and effector T cells and decreased Natural Killer (NK) cells in these tumors. Furthermore, transcriptomic data from the tumors uncovered a correlation between MARCO expression and the anti-inflammatory cytokine IL-37. In vitro studies subsequently showed that lung cancer cells polarized macrophages to express MARCO and gain an immune-suppressive phenotype through the release of IL-37. MARCO-expressing TAMs blocked cytotoxic T cell and NK cell activation, inhibiting their proliferation, cytokine production, and tumor killing capacity. Mechanistically, MARCO+ macrophages enhanced regulatory T (Treg) cell proliferation and IL-10 production and diminished CD8 T cell activities. Targeting MARCO or IL-37 receptor (IL-37R) by antibody or CRISPR knockout of IL-37 in lung cancer cell lines repolarized TAMs, resulting in recovered cytolytic activity and anti-tumoral capacity of NK cells and T cells and down-modulated Treg cell activities. In summary, our data demonstrate a novel immune therapeutic approach targeting human TAMs immune suppression of NK and T cell anti-tumor activities.

9.
J Cell Mol Med ; 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33336526

RESUMO

Early prognostication of neurological outcome in comatose patients after cardiac arrest (CA) is vital for clinicians when assessing the survival time of sufferers and formulating appropriate treatment strategies to avoid the withdrawal of life-sustaining treatment (WLST) from patients. However, there is still a lack of sensitive and specific serum biomarkers for early and accurate identification of these patients. Using an isobaric tag for relative and absolute quantitation (iTRAQ)-based proteomic approach, we discovered 55 differentially expressed proteins, with 39 up-regulated secreted serum proteins and 16 down-regulated secreted serum proteins between three comatose CA survivors with good versus poor neurological recovery. Then, four proteins were selected and were validated via an enzyme-linked immunosorbent assay (ELISA) approach in a larger-scale sample containing 32 good neurological outcome patients and 46 poor neurological outcome patients, and it was confirmed that serum angiotensinogen (AGT) and alpha-1-antitrypsin (SERPINA1) were associated with neurological function and prognosis in CA survivors. A prognostic risk score was developed and calculated using a linear and logistic regression model based on a combination of AGT, SERPINA1 and neuron-specific enolase (NSE) with an area under the curve of 0.865 (P < .001), and the prognostic risk score was positively correlated with the CPC value (R = 0.708, P < .001). We propose that the results of the risk score assessment not only reveal changes in biomarkers during neurological recovery but also assist in enhancing current therapeutic strategies for comatose CA survivors.

10.
Neuroscience ; 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33309967

RESUMO

The human nervous system is one of the most complicated systems in nature. Complex nonlinear behaviours have been shown from the single neuron level to the system level. For decades, linear connectivity analysis methods, such as correlation, coherence and Granger causality, have been extensively used to assess the neural connectivities and input-output interconnections in neural systems. Recent studies indicate that these linear methods can only capture a small amount of neural activities and functional relationships, and therefore cannot describe neural behaviours in a precise or complete way. In this review, we highlight recent advances in nonlinear system identification of neural systems, corresponding time and frequency domain analysis, and novel neural connectivity measures based on nonlinear system identification techniques. We argue that nonlinear modelling and analysis are necessary to study neuronal processing and signal transfer in neural systems quantitatively. These approaches can hopefully provide new insights to advance our understanding of neurophysiological mechanisms underlying neural functions. These nonlinear approaches also have the potential to produce sensitive biomarkers to facilitate the development of precision diagnostic tools for evaluating neurological disorders and the effects of targeted intervention.

11.
Int J Cancer ; 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33285000

RESUMO

The underlying molecular mechanisms involved in the pathogenesis of endometrial cancer (EC) are still not well understood. Our goal was to investigate the composition of the endometrial microbiota and the association with inflammatory cytokines in endometrial cancer. Endometrial microbiota profiles of women with endometrial cancer (n=25) and benign uterine lesions (BUL, n=25) were assessed by 16S ribosomal RNA gene amplicon sequencing. The expression levels of interleukin-6(IL-6), interleukin-8(IL-8), and interleukin-17(IL-17) mRNA and protein in the endometrial tissues of the two groups were determined by real-time quantitative polymerase chain reaction and Western blot, respectively. There were significant differences in alpha diversity based on the Observed OTUs (p=0.002), Pielou evenness(p=0.001), and Shannon index(p<0.001) between EC and BUL groups. Significant differences were also found in Bray-Curtis(p=0.001) and unweighted UniFrac(p=0.001) beta diversity measures between the two groups. At the genus level, Micrococcus was more abundant in the EC group. Pseudoramibacter_Eubacterium, Rhodobacter, Vogesella, Bilophila, Rheinheimera, and Megamonas were enriched in the BUL group. There were no differences in IL-8 and IL-17 protein levels between the two groups, except IL-6 protein levels. However, the mRNA expression levels of IL-6, IL-8, and IL-17 were significantly different. Moreover, the relative abundances of Micrococcus was positively correlated with IL-6, and IL-17 mRNA levels. In conclusion, our results suggested that dysbiosis of endometrial microbiota and the inflammatory cytokines were associated with Micrococcus in endometrial cancer patients, which might be useful for exploration of the mechanism between the endometrial microbiota and inflammatory responses in future studies.

12.
Curr Pharm Des ; 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33183190

RESUMO

Protein palmitoylation is a fundamental and reversible post-translational lipid modification that involves a series of biological processes. Although a large number of experimental studies have explored the molecular mechanism behind the palmitoylation process, the computational methods has attracted much attention for its good performance in predicting palmitoylation sites compared with expensive and time-consuming biochemical experiments. The prediction of protein palmitoylation sites is helpful to reveal its biological mechanism. Therefore, the research on the application of machine learning methods to predict palmitoylation sites has become a hot topic in bioinformatics and promoted the development in related fields. In this review, we briefly introduced the recent development in predicting protein palmitoylation sites by using machine learning-based methods and discussed their benefits and drawbacks. The perspective of machine learning-based methods in predicting palmitoylation sites was also provided. We hope the review could provide a guide in related fields.

13.
Biomed Pharmacother ; 133: 110990, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33232925

RESUMO

BACKGROUND: The NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome activation-mediated pyroptosis pathway has been linked to myocardial ischemia-reperfusion (MI/R) injury. This study explored whether uric acid (UA) aggravates MI/R injury through NLRP3 inflammasome-mediated pyroptosis. METHODS: In vivo, a mouse MI/R model was established by ligating the left coronary artery, and a mouse hyperuricemia model was created by intraperitoneal injection of potassium oxonate (PO). Then, the myocardial infarction (MI) size; terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) immunofluorescence; and serum levels of lactate dehydrogenase (LDH), creatine kinase isoenzyme (CK-MB), and UA, as well as the expression level of pyroptosis-related protein and caspase-3 in heart tissues, were measured. Separately, primary mouse cardiomyocytes were cultured in vitro to create a hypoxia/reoxygenation (H/R) model. We then compared cardiomyocytes viability, TUNEL immunofluorescence, and the levels of LDH, reactive oxygen species (ROS), and pyroptosis-related protein and caspase-3 in cardiomyocytes. RESULTS: In vivo, the MI area, levels of CK-MB and LDH, rate of cell death, and pyroptosis-related protein and the expression of caspase-3 were significantly higher in the MI/R group than in the sham group, and high UA levels worsened these changes. In vitro, cardiomyocytes viability was significantly downregulated, and the levels of ROS, LDH, pyroptosis-related protein, caspase-3, and the rate of cardiomyocyte death were significantly higher in the H/R + UA group compared with the HR group. Administration of an NLRP3 inflammasome inhibitor and ROS scavenger reversed these effects. CONCLUSION: UA aggravates MI/R-induced activation of the NLRP3 inflammatory cascade and pyroptosis by promoting ROS generation, while inflammasome inhibitors and ROS scavengers partly reverse the injury.

14.
ACS Appl Mater Interfaces ; 12(47): 52479-52491, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33196186

RESUMO

The development of near-infrared (NIR) laser triggered phototheranostics for multimodal imaging-guided combination therapy is highly desirable. However, multiple laser sources, as well as inadequate therapeutic efficacy, impede the application of phototheranostics. Here, we develop an all-in-one theranostic nanoagent PEGylated DCNP@DMSN-MoOx NPs (DCDMs) with a flower-like structure fabricated by coating uniformly sized down-conversion nanoparticles (DCNPs) with dendritic mesoporous silica (DMSN) and then loading the ultrasmall oxygen-deficient molybdenum oxide nanoparticles (MoOx NPs) inside through an electrostatic interaction. Owing to the doping of Nd ions, when excited by an 808 nm laser, DCNPs emit bright NIR-II emissions (1060 and 1300 nm), which have characteristic high spatial resolution and deep tissue penetration. In terms of treatment, MoOx NPs could be specifically activated by excessive hydrogen peroxide (H2O2) in the tumor microenvironment, thus generating 1O2 via the Russell mechanism. In addition, the excessive glutathione (GSH) in the tumor cells could be depleted through the Mo-mediated redox reaction, thus effectively decreasing the antioxidant capacity of tumor cells. Importantly, the excellent photothermal properties (photothermal conversion efficiency of 51.5% under an 808 nm laser) synergistically accelerate the generation of 1O2. This cyclic redox reaction of molybdenum indeed ensured the high efficacy of tumor-specific therapy, leaving the normal tissues unharmed. MoOx NPs could also efficiently catalyze tumor endogenous H2O2 into a considerable amount of O2 in an acidic tumor microenvironment, thus relieving hypoxia in tumor tissues. Moreover, the computed tomography (CT) and T1-weighted magnetic resonance imaging (MRI) effect from Gd3+ and Y3+ ions make DCNPs act as a hybrid imaging agent, allowing comprehensive analysis of tumor lesions. Both in vitro and in vivo experiments validate that such an "all-in-one" nanoplatform possesses desirable anticancer abilities under single laser source irradiation, benefiting from the NIR-II fluorescence/CT/MR multimodal imaging-guided photothermal/chemodynamic synergistic therapy. Overall, our strategy paves the way to explore other noninvasive cancer phototheranostics.

15.
Nanoscale ; 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33242048

RESUMO

Gasotransmitters with high therapeutic efficacy and biosafety have been drawing the attention of researchers. Nevertheless, how to effectively deliver gases to and precisely control their generation at the lesion as well as integrate them with other therapies to realize precision therapy have remained elusive. Herein, we report a versatile Cu2+-initiated nitric oxide (NO) nanocomposite for multimodal imaging-guided synergistic chemodynamic/photodynamic/gas therapy. After the nanomedicine was ingested by tumor cells, the acidic tumor microenvironment accelerated the decomposition of CuO2 and simultaneously triggered the Fenton-like catalytic reaction of Cu2+ and H2O2 to produce highly toxic ˙OH. By virtue of the NO generation and glutathione depletion, UMNOCC-PEG can relieve the antioxidant capacity and hypoxia of the tumor to improve the efficiency of chemodynamic therapy (CDT) and photodynamic therapy (PDT). Importantly, NO and reactive oxygen species (ROS) can generate reactive nitrogen species (RNS), which can result in DNA damage, further improving the therapeutic effect (cell apoptosis rate up to 93.4%). Moreover, the inherent properties of lanthanide ions endow UMNOCC-PEG with upconversion luminescence (UCL), CT and MRI trimodal imaging capability, achieving precise cancer treatment. By taking advantage of these features, the strategy developed here may provide a promising application foreground to conquer malignant tumors.

16.
J Mater Chem B ; 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33232438

RESUMO

Near infrared (NIR) light detonated phototherapy for cancer treatment based on photothermal therapy (PTT) and photodynamic therapy (PDT) has attracted increasing attention owing to its deep tissue penetration. However, the low absorption ability and therapeutic efficiency of the photosensitive drug have restricted the development of phototherapy to a great degree. Herein, a kind of IR808 dye sensitized glutathione (GSH) cladded Au-Bi bimetallic nanoparticles (Au-Bi-GSH@IR808) was prepared to enhance the inhibition effect of tumors. In this nanoplatform, the construction of GSH cladded Au-Bi bimetallic nanoparticles can effectively generate 1O2 while exhibiting outstanding photothermal conversion efficiency (η = 34.2%) upon 808 nm laser irradiation. Furthermore, IR808 as a small molecule dye endows the Au-Bi-GSH@IR808 with a higher 808 nm light absorption ability and stronger photothermal and photodynamic effects. The IR808 sensitized Au-Bi bimetallic nanoparticles with a small size (5 nm), hydrophilia and dispersible nature, exhibit a noticeably enhanced therapeutic peculiarity. Additionally, the prominent CT imaging property of Au-Bi-GSH@IR808 means it is expected to be used as a CT imaging contrast agent in clinical applications. The results of the in vitro and in vivo experiments indicate that the synthesized nanoparticles have an excellent ablation effect on cancer cells, and they are expected to be widely used in the accurate diagnosis and treatment of cancer.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33169349

RESUMO

This study investigated the functional role of p53-lincRNA-p21 in atherosclerosis (AS) by mediating the microRNA-17-5p (miR-17-5p)/SIRT7 axis. Peripheral blood was collected from AS patients, and an ApoE-/- mouse model of AS (AS-M) was induced by high-fat diet. The relationship among p53, lincRNA-p21, miR-17-5p, and SIRT7 was validated, and their effects on AS progression and vascular smooth muscle cell (VSMC) functions were analyzed using gain- and loss-of-function experiments in AS mice and human and mouse VSMCs. p53, lincRNA-p21, and SIRT7 were downregulated, and miR-17-5p was upregulated in AS-M and peripheral blood of AS patients. p53 positively regulated lincRNA-p21, while miR-17-5p, reversely targeted by lincRNA-p21, could target SIRT7. Overexpressing p53, lincRNA-p21, or SIRT7 contributed to impaired proliferation and promoted apoptosis of VSMCs in vitro as well as reducing the vulnerable plaque and lipid accumulation in AS mice. Collectively, p53-dependent lincRNA-p21 expression downregulated miR-17-5p, which consequently protecting against AS progression via SIRT7 elevation. Graphical abstract Collectively, p53-dependent lincRNA-p21 expression downregulated miR-17-5p, whichconsequently protecting against AS progression via SIRT7 elevation.

18.
J Mater Chem B ; 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33226055

RESUMO

The efficiency of photodynamic therapy (PDT) is severely constrained due to the innate hypoxic environment, besides the elevated level of glutathione (GSH). To get rid of the hypoxic environment and higher concentrations of GSH in the solid tumors, we propose an approach of oxygen self-sufficient multimodal imaging-guided nanocomposite CaO2-MnO2-UCNPs-Ce6/DOX (abbreviated as CaMn-NUC), in which CaO2 nanoparticles in the hydrophobic layer were seated on the hydrophilic MnO2 sheet and conjugated with chlorin e6 (Ce6) loaded upconversion nanoparticles (UCNPs-Ce6) via the click chemistry approach. CaMn-NUC was presented to overcome hypoxia and GSH-associated photodynamic resistance due to in situ oxygen generation and GSH reduction of MnO2 upon endocytosis, and a bulk amount of Mn2+ ions generated in the process under acidic tumor environment acts as the MRI contrast agent. Moreover, the MnO2 sheet protects Ce6 from self-degradation under irradiation; thus, it can be used to switch control of cellular imaging. Afterwards, in a regulated and targeted manner, the chemotherapeutic drug (doxorubicin hydrochloride, DOX) can be released with the degradation of CaMn-NUC in the acidic tumor microenvironment (TME). Thus, we testify a competent nanoplatform employing 808 nm-excited UCNPs-Ce6 for concurrent imaging and PDT in consideration of the large anti-Stokes shifts, deep penetration into biological tissues, narrow emission bands, and high spatial-temporal resolution of the UCNPs. Thus, our proposed nanoplatform postulates a strategy to efficiently kill cancer cells in a concentration- and time-dependent manner via the in situ oxygenation of solid tumor hypoxia to enhance the efficiency of multimodal imaging-guided chemo-photodynamic therapy.

19.
Opt Express ; 28(20): 30107-30116, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33114895

RESUMO

Continuous and reversible tuning of the properties of optical metasurfaces, as a functionality that would enable a range of device applications, has been a focus of the metasurface research field in recent years. Tuning mechanisms proposed and demonstrated so far have generally relied upon changing the morphology of a metasurface or the intrinsic properties of its constituent materials. Here we introduce, via numerical simulation, an alternative approach to achieve continuous tuning of gradient metasurface response, and illustrate its potential application to the challenge of continuous beam steering, as required for example in LIDAR and machine vision systems. It is based upon the coherent illumination of a silicon nano-pillar metasurface with two counter-propagating beams. Control of the input beams' relative phase and intensity enables tuning of the individual nano-pillars' electromagnetic response and thereby the phase gradient of the array, which in turn steers the direction of the output beam continuously over an angular range of approximately 9 degrees.

20.
Haematologica ; Online ahead of print: 0, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33124788

RESUMO

Not available.

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