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1.
J Appl Gerontol ; 41(12): 2469-2479, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35938737

RESUMO

This research accordingly examines the effect of childhood social relationships on the use of mobile payment and e-money among Chinese middle-aged and older adults from a life course perspective and tests the mediation role of social activities in such a path with the Karlson-Holm-Breen (KHB) method. The findings support that good childhood community relationships, peer relationships, and close relationships positively affect mobile payment and electronic money use when people enter middle and old age. These effects are significantly mediated by social activities in later life. The findings make marginal contributions to life course theory (LCT), with practical implications for individuals, commercial enterprises, governments, and societies in their efforts to facilitate a society that promotes the digital inclusion of middle-aged and older adults.


Assuntos
Exclusão Digital , Humanos , Pessoa de Meia-Idade , Idoso , Relações Interpessoais , China
2.
ACS Nano ; 12(10): 10272-10280, 2018 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-30272942

RESUMO

The utility of layer-by-layer (LbL) coated microneedle (MN) skin patches for transdermal drug delivery has proven to be a promising approach, with advantages over hypodermal injection due to painless and easy self-administration. However, the long epidermal application time required for drug implantation by existing LbL MN strategies (15-90 min) can lead to potential medication noncompliance. Here, we developed a MN platform to shorten the application time in MN therapies based on a synthetic pH-induced charge-invertible polymer poly(2-(diisopropylamino) ethyl methacrylate- b-methacrylic acid) (PDM), requiring only 1 min skin insertion time to implant LbL films in vivo. Following MN-mediated delivery of 0.5 µg model antigen chicken ovalbumin (OVA) in the skin of mice, this system achieved sustained release over 3 days and led to an elevated immune response as demonstrated by significantly higher humoral immunity compared with OVA administration via conventional routes (subcutaneously and intramuscularly). Moreover, in an ex vivo experiment on human skin, we achieved efficient immune activation through MN-delivered LbL films, demonstrated by a rapid uptake of vaccine adjuvants by the antigen presenting cells. These features, rapid administration and the ability to elicit a robust immune response, can potentially enable a broad application of microneedle-based vaccination technologies.


Assuntos
Adjuvantes Imunológicos/farmacologia , Agulhas , Oligodesoxirribonucleotídeos/farmacologia , Ácidos Polimetacrílicos/síntese química , Receptor de Morte Celular Programada 1/imunologia , Pele/efeitos dos fármacos , Adjuvantes Imunológicos/administração & dosagem , Administração Cutânea , Animais , Galinhas , Sistemas de Liberação de Medicamentos , Feminino , Citometria de Fluxo , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Endogâmicos C57BL , Oligodesoxirribonucleotídeos/administração & dosagem , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Ácidos Polimetacrílicos/química , Pele/imunologia , Vacinação
3.
ACS Nano ; 11(3): 2531-2544, 2017 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-28157292

RESUMO

Messenger RNA (mRNA) represents a promising class of nucleic-acid-based therapeutics. While numerous nanocarriers have been developed for mRNA delivery, the inherent labile nature of mRNA results in a very low transfection efficiency and poor expression of desired protein. Here we preassemble the mRNA translation initiation structure through an inherent molecular recognition between 7-methylguanosine (m7G)-capped mRNA and eukaryotic initiation factor 4E (eIF4E) protein to form ribonucleoproteins (RNPs), thereby mimicking the first step of protein synthesis inside cells. Subsequent electrostatic stabilization of RNPs with structurally tunable cationic carriers leads to nanosized complexes (nanoplexes), which elicit high levels of mRNA transfection in different cell types by enhancing intracellular mRNA stability and protein synthesis. By investigating a family of synthetic polypeptides bearing different side group arrangements of cationic charge, we find that the molecular structure modulates the nanoscale distance between the mRNA strand and the eIF4E protein inside the nanoplex, which directly impacts the enhancement of mRNA transfection. To demonstrate the biomedical potential of this approach, we use this approach to introduce mRNA/eIF4E nanoplexes to murine dendritic cells, resulting in increased activation of cytotoxic CD8 T cells ex vivo. More importantly, eIF4E enhances gene expression in lungs following a systemic delivery of luciferase mRNA/eIF4E in mice. Collectively, this bioinspired molecular assembly method could lead to a new paradigm of gene delivery.


Assuntos
Fator de Iniciação 4E em Eucariotos/genética , Técnicas de Transferência de Genes , Nanopartículas/química , Iniciação Traducional da Cadeia Peptídica/genética , Capuzes de RNA/genética , RNA Mensageiro/genética , Fator de Iniciação 4E em Eucariotos/química , Conformação de Ácido Nucleico , Biossíntese de Proteínas , RNA Mensageiro/química
4.
Chemistry ; 20(20): 5977-82, 2014 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-24700506

RESUMO

Ba6Zn6ZrS14 was synthesized by a traditional salt-melt method with KI as flux. The pale yellow crystals of Ba6Zn6ZrS14 crystallize in the tetragonal space group I4/mcm with a=16.3481 (4) Šand c=9.7221(6) Å. The structure features unique one-dimensional parallel [Zn6S9](6-) and [ZrS5](6-) straight chains. The D2h-symmetric [Zn6S9](6-) cluster serves as the building block of the [Zn6S9](6-) chains. A powder sample was investigated by X-ray diffraction, optical absorption, and photoluminescence measurements. The compound shows multiple-absorption character with three optical absorption edges around 1.78, 2.50, and 2.65 eV, respectively, which are perfectly consistent with the results of first-principles calculations. Analysis of the density of states further revealed that the three optical absorption bands are attributable to the three S(3p(6))→Zr(4d(0)) transitions due to the splitting of the Zr 4d orbitals in the D4h crystal field. The multiband nature of Ba6Zn6ZrS14 also results in photocatalytic activity under visible-light irradiation and three band-edge emissions.

5.
ACS Appl Mater Interfaces ; 6(5): 3088-92, 2014 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-24552292

RESUMO

We report a new rapid household microwave method to successfully grow graphene on h-BN flakes without using any catalysts. We obtained a novel uniform multilevel matrix of vertical graphene sheets on h-BN flakes. The unique structure possessed outstanding electron conductivity and thermal properties (29.1 W m(-1) K(-1)).

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