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Guo-Xing Li Xiao-Wei Qu Lu-Wei Hao Qing Li Su Chen 《Journal of polymer science. Part A, Polymer chemistry》2022,60(11):1710-1717
From the implementation point of view, the printable magnetic Janus colloidal photonic crystals (CPCs) microspheres are highly desirable. Herein, we developed a dispensing-printing strategy for magnetic Janus CPCs display via a microfluidics-automatic printing system. Monodisperse core/shell colloidal particles and magnetic Fe3O4 nanoparticles precursor serve as inks. Based on the equilibrium of three-phase interfacial tensions, Janus structure is successfully formed, followed by UV irradiation and self-assembly of colloid particle to generate magnetic Janus CPCs microspheres. Notably, this method shows distinct superiority with highly uniform Janus CPCs structure, where the TMPTA/Fe3O4 hemisphere is in the bottom side while CPCs hemisphere is in the top side. Thus, by using Janus CPCs microspheres with two different structural colors as pixel points, a pattern with red flower and green leaf is achieved. Moreover, 1D linear Janus CPCs pattern encapsulated by hydrogel is also fabricated. Both the color and the shape can be changed under the traction of magnets, showing great potentials in flexible smart displays. We believe this work not only offers a new feasible pathway to construct magnetic Janus CPCs patterns by a dispensing-printable fashion, but also provides new opportunities for flexible and smart displays. 相似文献
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Atopic dermatitis is characterized by leukocyte migration into the skin dermis and typically driven by excessive chemokine production at the site of inflammation. Conventional topical formulations such as gels, creams, and ointments are insufficient for this treatment because of low penetration of drug molecules into the targeted skin tissues. Herein, using a simple, green, sustainable strategy, we have developed novel primary zein nanoparticles embedded in curcumin (Cur) and coated with silk sericin (ZHSCs) for the topical delivery of Cur to penetrate into the dermis and exercise anti-dermatitis effects on the lesion with minimal side-effects. Transdermal delivery experiments and porcine skin fluorescence imaging indicated that ZHSCs facilitate the penetration of Cur across the epidermis layer of skin to reach deep-seated sites. Notably, ZHSCs = 1:0.25 (zein-to-silk sericin mass ratios of 1:0.25) markedly elevated the skin permeability and cumulative turnover of Cur transferred, which were provided a greater than a 3.8-fold increase relative to free Cur. The special nanoparticles of ZHS = 1:0.25 possessed the deepest localization depth and experience a transition of the particle structure and core-shell separation after penetrating into the dermis of skin. In a cell model of dermatitis induced by tumor necrosis factor α/interferon γ co-stimulation, compared with free Cur, Cur-loaded ZHS nanoparticles down-regulated the generation of inflammatory cytokines and chemokines in keratinocytes through suppression of the nuclear translocation of NF-κBp65 and hence exerted an anti-dermatitis effect. This strategy may provide new avenues and direction for the demanding issues of valid topical delivery systems. 相似文献
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Kang Il Yoo Ji Yeong Jeon Su Jeong Ryu Giri Nam Hyewon Youn Eun Young Choi 《Experimental & molecular medicine》2015,47(2):e140
In allogeneic transplantation, including the B6 anti-BALB.B settings, H60 and H4 are two representative dominant minor histocompatibility antigens that induce strong CD8 T-cell responses. With different distribution patterns, H60 expression is restricted to hematopoietic cells, whereas H4 is ubiquitously expressed. H60-specific CD8 T-cell response has been known to be dominant in most cases of B6 anti-BALB.B allo-responses, except in the case of skin transplantation. To understand the mechanism underlying the subdominance of H60 during allogeneic skin transplantation, we investigated the dynamics of the H60-specific CD8 T cells in B6 mice transplanted with allogeneic BALB.B tail skin. Unexpectedly, longitudinal bioluminescence imaging and flow cytometric analyses revealed that H60-specific CD8 T cells were not always subdominant to H4-specific cells but instead showed a brief dominance before the H4 response became predominant. H60-specific CD8 T cells could expand in the draining lymph node and migrate to the BALB.B allografts, indicating their active participation in the anti-BALB.B allo-response. Enhancing the frequencies of H60-reactive CD8 T cells prior to skin transplantation reversed the immune hierarchy between H60 and H4. Additionally, H60 became predominant when antigen presentation was limited to the direct pathway. However, when antigen presentation was restricted to the indirect pathway, the expansion of H60-specific CD8 T cells was limited, whereas H4-specific CD8 T cells expanded significantly, suggesting that the temporary immunodominance and eventual subdominance of H60 could be due to their reliance on the direct antigen presentation pathway. These results enhance our understanding of the immunodominance phenomenon following allogeneic tissue transplantation. 相似文献
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Su X. F. Zhang Y. L. Maximov A. L. Zhang K. Xin Q. Feng C. Q. Bai X. F. Wu W. 《Russian Journal of Applied Chemistry》2020,93(1):127-136
Russian Journal of Applied Chemistry - Nanoscale ZSM-5 (AlZ5-D) and Ga-substituted ZSM-5 zeolites ((Al,Ga)Z5-D and GaZ5-D) were synthesized by a green dry-gel conversion strategy. For comparison,... 相似文献
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Journal of Thermal Analysis and Calorimetry - In the present work, pyrolysis kinetic mechanism was studied for regenerated cellulosic fiber (RCF) and composite RCF containing silicon/nitrogen flame... 相似文献
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