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1.
Int J Nanomedicine ; 19: 3737-3751, 2024.
Article in English | MEDLINE | ID: mdl-38699684

ABSTRACT

Background: Chemo-photodynamic combination therapy has demonstrated significant potential in the treatment of cancer. Triptolide (TPL), a naturally derived anticancer agent, when combined with the photosensitizer Chlorin e6 (Ce6), has shown to provide enhanced anti-tumor benefits. However, the development of stimuli-responsive nanovehicles for the co-delivery of TPL and Ce6 could further enhance the efficacy of this combination therapy. Methods: In this study, we synthesized a pH/ROS dual-responsive mPEG-TK-PBAE copolymer, which contains a pH-sensitive PBAE moiety and a ROS-sensitive thioketal (TK) linkage. Through a self-assembly process, TPL and Ce6 were successfully co-loaded into mPEG-TK-PBAE nanoparticles, hereafter referred to as TPL/Ce6 NPs. We evaluated the pH- and ROS-sensitive drug release and particle size changes. Furthermore, we investigated both the in vitro suppression of cellular proliferation and induction of apoptosis in HepG2 cells, as well as the in vivo anti-tumor efficacy of TPL/Ce6 NPs in H22 xenograft nude mice. Results: The mPEG-TK-PBAE copolymer was synthesized through a one-pot Michael-addition reaction and successfully co-encapsulated both TPL and Ce6 by self-assembly. Upon exposure to acid pH values and high ROS levels, the payloads in TPL/Ce6 NPs were rapidly released. Notably, the abundant ROS generated by the released Ce6 under laser irradiation further accelerated the degradation of the nanosystem, thereby amplifying the tumor microenvironment-responsive drug release and enhancing anticancer efficacy. Consequently, TPL/Ce6 NPs significantly increased PDT-induced oxidative stress and augmented TPL-induced apoptosis in HepG2 cells, leading to synergistic anticancer effects in vitro. Moreover, administering TPL/Ce6 NPs (containing 0.3 mg/kg of TPL and 4 mg/kg of Ce6) seven times, accompanied by 650 nm laser irradiation, efficiently inhibited tumor growth in H22 tumor-bearing mice, while exhibiting lower systemic toxicity. Conclusion: Overall, we have developed a tumor microenvironment-responsive nanosystem for the co-delivery of TPL and Ce6, demonstrating amplified synergistic effects of chemo-photodynamic therapy (chemo-PDT) for hepatocellular carcinoma (HCC) treatment.


Subject(s)
Apoptosis , Chlorophyllides , Diterpenes , Liver Neoplasms , Mice, Nude , Phenanthrenes , Photochemotherapy , Photosensitizing Agents , Porphyrins , Reactive Oxygen Species , Animals , Humans , Photochemotherapy/methods , Reactive Oxygen Species/metabolism , Hep G2 Cells , Liver Neoplasms/drug therapy , Porphyrins/chemistry , Porphyrins/pharmacology , Porphyrins/administration & dosage , Porphyrins/pharmacokinetics , Diterpenes/chemistry , Diterpenes/pharmacology , Diterpenes/pharmacokinetics , Diterpenes/administration & dosage , Hydrogen-Ion Concentration , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , Photosensitizing Agents/administration & dosage , Apoptosis/drug effects , Mice , Carcinoma, Hepatocellular/drug therapy , Epoxy Compounds/chemistry , Epoxy Compounds/pharmacology , Epoxy Compounds/administration & dosage , Nanoparticles/chemistry , Xenograft Model Antitumor Assays , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/administration & dosage , Drug Liberation , Cell Proliferation/drug effects , Polyethylene Glycols/chemistry , Combined Modality Therapy
2.
Nano Lett ; 24(5): 1784-1791, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38265953

ABSTRACT

Selective control of light is essential for optical science and technology, with numerous applications. However, optical selectivity in the angular momentum of light has been quite limited, remaining constant by increasing the incident light power on previous passive optical devices. Here, we demonstrate a nonlinear boost of optical selectivity in both the spin and orbital angular momentum of light through near-field selective excitation of single-mode nanolasers. Our designed hybrid nanolaser circuits consist of plasmonic metasurfaces and individually placed perovskite nanowires, enabling subwavelength focusing of angular-momentum-distinctive plasmonic fields and further selective excitation of nanolasers in nanowires. The optically selected nanolaser with a nonlinear increase of light emission greatly enhances the baseline optical selectivity offered by the metasurface from about 0.4 up to near unity. Our demonstrated hybrid nanophotonic platform may find important applications in all-optical logic gates and nanowire networks, ultrafast optical switches, nanophotonic detectors, and on-chip optical and quantum information processing.

3.
RSC Adv ; 13(9): 5893-5899, 2023 Feb 14.
Article in English | MEDLINE | ID: mdl-36816078

ABSTRACT

Two-dimensional layered (BA)2PbI4 (BA = C4H9NH3) perovskites are emerging as a new class of layered materials and show great potential in optoelectronic applications. Elucidating how exciton-phonon interaction affects the excitonic emission is of great importance for a better knowledge of their optoelectronic properties. In this letter, we synthesized high-quality (BA)2PbI4 microplates via solution methods, and dual-excitonic emission peaks (surface-emission and interior-emission) were detected from the as-grown samples at low temperatures. Furthermore, we determine the energies for the longitudinal optical phonon modes to be ∼27 and ∼18 meV, and the exciton-phonon coupling strengths to be ∼177 and ∼21 meV for the surface-emission and interior-emission bands, respectively. Compared to the interior-emission band, the stronger exciton-phonon interaction results in a considerable degree of spectral broadening and red-shift for the surface-emission with increasing temperature. In contrast, the (OA)2PbI4 (OA = C8H17NH2) microplates with longer alkyl chains between Pb-I layers, exhibit only one excitonic emission peak, as well as a large exciton-phonon coupling strength. Our work clarifies the influence of exciton-phonon coupling on the excitonic emission of (BA)2PbI4 microplates, and also suggests the intrinsic relationship between the exciton-phonon coupling and the length of organic carbon chain ligands.

4.
Asian J Pharm Sci ; 17(2): 206-218, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35582637

ABSTRACT

The combination of Ce6, an acknowledged photosensitizer, and TPL, a natural anticancer agent, has been demonstrated as a useful strategy to reinforce the tumor growth suppression, as well as decrease the systemic side effects compared with their monotherapy. However, in view of the optimal chemo-photodynamic combination efficiency, there is still short of the feasible nanovehicle to steadily co-deliver Ce6 and TPL, and stimuli-responsively burst release drugs in tumor site. Herein, we described the synergistic antitumor performance of a pH-sensitive supramolecular nanosystem, mediated by the host-guest complexing between ß-CD and acid pH-responsive amphiphilic co-polymer mPEG-PBAE-mPEG, showing the shell-core structural micelles with the tight ß-CD layer coating. Both Ce6 and TPL were facilely co-loaded into the spherical supramolecular NPs (TPL+Ce6/NPs) by one-step nanoprecipitation method, with an ideal particle size (156.0 nm), acid pH-responsive drug release profile, and enhanced cellular internalization capacity. In view of the combination benefit of photodynamic therapy and chemotherapy, as well as co-encapsulation in the fabricated pH-sensitive supramolecular NPs, TPL+Ce6/NPs exhibited significant efficacy to suppress cellular proliferation, boost ROS level, lower MMP, and promote cellular apoptosis in vitro. Particularly, fluorescence imaging revealed that TPL+Ce6/NPs preferentially accumulated in the tumor tissue area, with higher intensity than that of free Ce6. As expected, upon 650-nm laser irradiation, TPL+Ce6/NPs exhibited a cascade of amplified synergistic chemo-photodynamic therapeutic benefits to suppress tumor progression in both hepatoma H22 tumor-bearing mice and B16 tumor-bearing mice. More importantly, lower systemic toxicity was found in the tumor-bearing mice treated with TPL+Ce6/NPs. Overall, the designed supramolecular TPL+Ce6/NPs provided a promising alternative approach for chemo-photodynamic therapy in tumor treatment.

5.
Nat Chem Biol ; 17(12): 1230-1237, 2021 12.
Article in English | MEDLINE | ID: mdl-34556863

ABSTRACT

Cholecystokinin receptors, CCKAR and CCKBR, are important neurointestinal peptide hormone receptors and play a vital role in food intake and appetite regulation. Here, we report three crystal structures of the human CCKAR in complex with different ligands, including one peptide agonist and two small-molecule antagonists, as well as two cryo-electron microscopy structures of CCKBR-gastrin in complex with Gi2 and Gq, respectively. These structures reveal the recognition pattern of different ligand types and the molecular basis of peptide selectivity in the cholecystokinin receptor family. By comparing receptor structures in different conformational states, a stepwise activation process of cholecystokinin receptors is proposed. Combined with pharmacological data, our results provide atomic details for differential ligand recognition and receptor activation mechanisms. These insights will facilitate the discovery of potential therapeutics targeting cholecystokinin receptors.


Subject(s)
Devazepide/chemistry , Receptors, Cholecystokinin/chemistry , Amino Acid Sequence , Cryoelectron Microscopy , Crystallization , Humans , Indoleacetic Acids/chemistry , Ligands , Models, Molecular , Protein Binding , Protein Conformation , Receptors, Cholecystokinin/genetics , Structure-Activity Relationship , Thiazoles/chemistry
6.
Nano Lett ; 21(14): 6220-6227, 2021 Jul 28.
Article in English | MEDLINE | ID: mdl-34264683

ABSTRACT

Plasmonic nanostructures can enable compact multiplexing of the orbital angular momentum (OAM) of light; however, strong dissipation of the highly localized OAM-distinct plasmonic fields in the near-field region hinders on-chip OAM transmission and processing. Superior transmission efficiency is offered by semiconductor nanowires sustaining highly confined optical modes, but only the polarization degree of freedom has been utilized for their selective excitation. Here we demonstrate that incident OAM beams can selectively excite single-crystalline cadmium sulfide (CdS) nanowires through coupling OAM-distinct plasmonic fields into nanowire waveguides for long-distance transportation. This allows us to build an OAM-controlled hybrid nanowire circuit for optical logic operations including AND and OR gates. In addition, this circuit enables the on-chip photoluminescence readout of OAM-encrypted information. Our results open exciting new avenues not only for nanowire photonics to develop OAM-controlled optical switches, logic gates, and modulators but also for OAM photonics to build ultracompact photonic circuits for information processing.

7.
Nat Commun ; 11(1): 6328, 2020 Dec 10.
Article in English | MEDLINE | ID: mdl-33303755

ABSTRACT

Light-induced halide segregation limits the bandgap tunability of mixed-halide perovskites for tandem photovoltaics. Here we report that light-induced halide segregation is strain-activated in MAPb(I1-xBrx)3 with Br concentration below approximately 50%, while it is intrinsic for Br concentration over approximately 50%. Free-standing single crystals of CH3NH3Pb(I0.65Br0.35)3 (35%Br) do not show halide segregation until uniaxial pressure is applied. Besides, 35%Br single crystals grown on lattice-mismatched substrates (e.g. single-crystal CaF2) show inhomogeneous segregation due to heterogenous strain distribution. Through scanning probe microscopy, the above findings are successfully translated to polycrystalline thin films. For 35%Br thin films, halide segregation selectively occurs at grain boundaries due to localized strain at the boundaries; yet for 65%Br films, halide segregation occurs in the whole layer. We close by demonstrating that only the strain-activated halide segregation (35%Br/45%Br thin films) could be suppressed if the strain is properly released via additives (e.g. KI) or ideal substrates (e.g. SiO2).

8.
Exp Ther Med ; 18(5): 3893-3904, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31602250

ABSTRACT

The aim of this study was to systematically search literature and conduct a meta-analysis comparing the clinical efficacy and safety of Evolut R and Sapien 3 valves for transcatheter aortic valve implantation (TAVI). The PubMed, Biomed Central, Scopus, Cochrane library and Google scholar databases were searched for articles published up to June, 2019. A total of 5 studies were included. In total, 795 patients underwent TAVI with Evolut R, while 665 patients received the Sapien 3 valve in the included studies. Overall device success with Evolut R was 95.7% and with Sapien 3 was 94.2%. Pooled data indicated no significant differences between the 2 valves (OR, 1.12; 95% CI, 0.66-1.89; P=0.68; I2=0%). No significant differences were observed in the incidence of none to mild paravalvular leakage between the 2 groups (OR, 1.71; 95% CI, 0.83-3.54; P=0.14; I2=0%). Both mean [random; mean difference (MD) = -3.96; 95% CI, -4.61 to -3.31; P<0.00001, I2=0%] and peak (random; MD = -6.85; 95% CI, -8.22 to -5.48; P<0.00001, I2=0%) aortic valve gradients were significantly lower with Evolut R. No significant differences were observed in the 30-day mortality (OR, 1.32; 95% CI, 0.45-3.87; P=0.62; I2=0%) or 30-day stroke outcomes (OR, 0.76; 95% CI, 0.32-1.81; P=0.54; I2=0%) between the 2 devices. On the whole, the findings of this study indicate that Evolut R and Sapien 3 valves may be comparable in terms of device success and short-term complications. The differences between the 2 devices for post-operative moderate to severe paravalvular leak and permanent pacemaker implantation remain unclear. There is thus a need for a large multi-center randomized controlled trial to provide stronger evidence on this subject.

9.
Nanoscale Adv ; 1(1): 168-176, 2019 Jan 15.
Article in English | MEDLINE | ID: mdl-36132482

ABSTRACT

In this work, the treatment of textile wastewater by a facile and high-efficiency technology using eco-friendly Aspergillus niger as a biosorbent was investigated. We measured physical changes (weight, size) during the formation and growth of fungus pellets and the pH values that influence the adsorption performance and biosorption mechanism. Three acid anionic dyes containing Acid Orange 56, Acid Blue 40 and Methyl Blue were chosen as model dyes to investigate batch adsorption efficiency. Two adsorption models (in vivo and in vitro) were adopted to decolorize the acid dyes. The results show that fungus pellets have excellent decoloration abilities with a high adsorption efficiency of 98% for 200 mg L-1 of acid dye. The pH value of the dye solution varied with the adsorption time and the dye removal efficiency greatly depended on the pH. The bioadsorption mechanism of nano-scale hyphae was revealed to be mainly due to electrostatic interactions caused by the pH change. Furthermore, the surface morphologies of the fungus after adsorption indicated that the dyes had been adsorbed on the surface of the fungus mycelia. Moreover, prepared 3D fungus/GO aerogels demonstrated superior dye removal abilities compared with fungus aerogels.

10.
Mater Sci Eng C Mater Biol Appl ; 69: 255-61, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-27612711

ABSTRACT

To develop lightweight biomimetic composite structures, the compressive failure and mechanical properties of fully integrated honeycomb plates were investigated experimentally and through the finite element method. The results indicated that: fracturing of the fully integrated honeycomb plates primarily occurred in the core layer, including the sealing edge structure. The morphological failures can be classified into two types, namely dislocations and compactions, and were caused primarily by the stress concentrations at the interfaces between the core layer and the upper and lower laminations and secondarily by the disordered short-fiber distribution in the material; although the fully integrated honeycomb plates manufactured in this experiment were imperfect, their mass-specific compressive strength was superior to that of similar biomimetic samples. Therefore, the proposed bio-inspired structure possesses good overall mechanical properties, and a range of parameters, such as the diameter of the transition arc, was defined for enhancing the design of fully integrated honeycomb plates and improving their compressive mechanical properties.


Subject(s)
Biomimetic Materials/chemistry , Bone Plates , Compressive Strength , Microscopy, Electron, Scanning , Models, Biological
11.
Materials (Basel) ; 9(3)2016 Feb 25.
Article in English | MEDLINE | ID: mdl-28773253

ABSTRACT

Multifuntional fabrics with special wettability have attracted a lot of interest in both fundamental research and industry applications over the last two decades. In this review, recent progress of various kinds of approaches and strategies to construct super-antiwetting coating on cellulose-based substrates (fabrics and paper) has been discussed in detail. We focus on the significant applications related to artificial superhydrophobic fabrics with special wettability and controllable adhesion, e.g., oil-water separation, self-cleaning, asymmetric/anisotropic wetting for microfluidic manipulation, air/liquid directional gating, and micro-template for patterning. In addition to the anti-wetting properties and promising applications, particular attention is paid to coating durability and other incorporated functionalities, e.g., air permeability, UV-shielding, photocatalytic self-cleaning, self-healing and patterned antiwetting properties. Finally, the existing difficulties and future prospects of this traditional and developing field are briefly proposed and discussed.

12.
Mater Sci Eng C Mater Biol Appl ; 50: 286-93, 2015 May.
Article in English | MEDLINE | ID: mdl-25746272

ABSTRACT

Honeycomb plates can be applied in many fields, including furniture manufacturing, mechanical engineering, civil engineering, transportation and aerospace. In the present study, we discuss the simulated effect on the mechanical properties of bionic integrated honeycomb plates by investigating the compressive and shear failure modes and the mechanical properties of trabeculae reinforced by long or short fibers. The results indicate that the simulated effect represents approximately 80% and 70% of the compressive and shear strengths, respectively. Compared with existing bionic samples, the mass-specific strength was significantly improved. Therefore, this integrated honeycomb technology remains the most effective method for the trial manufacturing of bionic integrated honeycomb plates. The simulated effect of the compressive rigidity is approximately 85%. The short-fiber trabeculae have an advantage over the long-fiber trabeculae in terms of shear rigidity, which provides new evidence for the application of integrated bionic honeycomb plates.


Subject(s)
Bionics/methods , Compressive Strength , Mechanical Phenomena , Shear Strength , Stress, Mechanical , Materials Testing , Silicates/chemistry
13.
J Org Chem ; 78(14): 7093-9, 2013 Jul 19.
Article in English | MEDLINE | ID: mdl-23795619

ABSTRACT

Novel C60 derivatives of a singly bonded dimer and a 1,4-adduct bearing a sulfonic acid functionality have been prepared via the electroreductive transformation of a [60]fullerosultone. It has been shown that the reaction of the in situ formed dianion with benzyl bromide is initiated by a ring-opening of the [60]fullerosultone via the C60-O bond cleavage upon receiving one electron. The [60]fullerosultone dianion is electrooxidized at 0.40 V to afford the singly bonded dimer species, which can be further electrooxidized at 1.30 V to restore the starting material [60]fullerosultone. The reaction mechanism is studied with the cyclic voltammetry and vis-NIR spectroscopy.


Subject(s)
Benzenesulfonates/chemistry , Electrochemical Techniques , Fullerenes/chemistry , Molecular Structure , Oxidation-Reduction
14.
PLoS One ; 8(6): e66252, 2013.
Article in English | MEDLINE | ID: mdl-23776645

ABSTRACT

BACKGROUND: Many studies have considered the prevalence of dementia in mainland China, Hong Kong and Taiwan. However, area level estimates have not been produced. This study examines area differences across mainland China, Hong Kong and Taiwan adjusting for the effect of methodological factors with the aim of producing estimates of the numbers of people with dementia in these areas. METHOD AND FINDINGS: A search of Chinese and English databases identified 76 dementia prevalence studies based on samples drawn from mainland China, Hong Kong and Taiwan between 1980 and 2012. A pattern of significantly decreasing prevalence was observed from northern, central, southern areas of mainland China, Hong Kong and Taiwan. Area variations in dementia prevalence were not explained by differences in methodological factors (diagnostic criteria, age range, study sample size and sampling method), socioeconomic level or life expectancy between areas. The results of meta-analysis were applied to current population data to provide best estimate. Based on the DSM-IV diagnostic criteria, the total number of people aged 60 and over with dementia in mainland China, Hong Kong and Taiwan is 8.4 million (4.6%, 95% CI: 3.4, 5.8) and in northern, central and southern areas are 3.8 (5.1%, 95% CI: 4.1, 6.1), 3.2 (4.4%, 95% CI: 3.2, 5.6) and 1.2 (3.9%, 95% CI: 2.3, 5.4) million respectively. These estimates were mainly based on the studies existing in highly developed areas and potentially affected by incomplete and insufficient data. CONCLUSIONS: The findings of this review provide a robust estimate of area differences in dementia prevalence. Application of the estimated prevalence to population data reveals the number of people with dementia is expected to double every 20 years, areas in mainland China will be facing the greatest dementia challenge.


Subject(s)
Dementia/epidemiology , China/epidemiology , Female , Humans , Male , Taiwan/epidemiology
15.
Org Lett ; 15(7): 1532-5, 2013 Apr 05.
Article in English | MEDLINE | ID: mdl-23496090

ABSTRACT

The silver carbonate promoted reaction of [60]fullerene with (Z)-N-arylbenzamidines afforded the unprecedented C60-fused imidazoline derivatives in high yields. Substrates with both electron-donating and -withdrawing groups on aromatic rings could be employed. In addition, the electrochemistry and further selective functionalization of the obtained C60-fused imidazolines were investigated.


Subject(s)
Fullerenes/chemistry , Imidazolines/chemical synthesis , Carbonates/chemistry , Catalysis , Combinatorial Chemistry Techniques , Imidazolines/chemistry , Molecular Structure , Silver Compounds/chemistry
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