Browsing by Author "Wang, Yen-Jen"

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Biomedical applications and colloidal properties of amphiphilically modified chitosan hybrids
(2013-09-01)
Larsson, Mikael
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Huang, Wei-Chen
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Hsiao, Meng-Hsuan
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Wang, Yen-Jen
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Nyden, Magnus
Chitosan is among the most abundant biopolymers on earth and has been either used or exhibited potential in a wide variety of industrial and biomedical applications. With the advancement of materials technologies, chitosan has been chemically modified to self-assemble into nanoarchitectures that are usable in advanced biomedical applications, such as drug nanocarriers, macroscopic injectables, tissue-engineering scaffolds, and nanoimaging agents. Colloidal amphiphilically modified chitosan (AMC) is a relatively recent material receiving increased attention with numerous publications addressing the medical advantages of specific systems. To date, many reviews have focused on the synthesis and biomedical properties of chitosan-based biomaterials, but a comprehensive study focusing on the colloidal properties of AMC in relation to biomedical performance appears to be lacking. This review provides a survey of the field, critically reviewing the colloidal properties and biomedical performance of AMC systems, such as nanoparticle drug delivery systems and macroscopic medical devices. Finally, the future development, market potential, and clinical implications of these promising colloidal-structured biomaterials are summarised. (C) 2013 Elsevier Ltd. All rights reserved.
Demethoxycurcumin-Carrying Chitosan Antibody Core Shell Nanoparticles with Multitherapeutic Efficacy toward Malignant A549 Lung Tumor: From in Vitro Characterization to in Vivo Evaluation
(2015-04-01)
Huang, Wei-Ting
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Larsson, Mikael
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Wang, Yen-Jen
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Chiou, Shih-Hwa
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Lin, Hui-Yi
Targeting controlled release core-shell nanocarriers with the potential to overcome multidrug resistant (MDR) lung cancer were prepared based on demethoxycurcumin (DMC) loaded amphiphilic chitosan nanoparticles coated with an anti-EGFR antibody layer. The nanocarriers were characterized with regard to size with dynamic light scattering, SEM, and TEM. The characterization confirmed the nanocarriers to have a surface coating of the anti-EGFR antibody and a final size excellently suited for circulating targeting nanocarriers, i.e., <200 nm in diameter. In vitro drug release revealed extended quasi-Fickian release from the nanocarriers, with the anti-EGFR layer further reducing the release rate. Cell culture experiments using normoxic and MDR hypoxic cells overexpressing EGFR confirmed improved DMC delivery for anti-EGFR coated particles and revealed that the DMC was delivered to the cytoplasmic region of the cells, forming nanoprecipitates in lysosomes and endosomes. The effective endocytosis and targeting of the core-shell nanoparticles resulted in the nanocarriers achieving high cytotoxicity also against MDR cells. The therapeutic potential was further confirmed in an A549 xenograft lung tumor mouse model, where DMC loaded core-shell nanocarriers achieved about 8-fold reduction in tumor volume compared with control group over the 8 weeks of the investigation. Both in vitro and in vivo data suggest the anti-EGFR coated core-shell nanocarriers as highly promising for treatment of hypoxic MDR cancers, especially for non-small cell lung cancer.
Electrophoretic coating of amphiphilic chitosan colloids on regulating cellular behaviour
(2013-09-06)
Wang, Yen-Jen
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Lo, Teng-Yuan
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Wu, Chieh-Hsi
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Liu, Dean-Mo
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材料科學與工程學系
In this communication, we report a facile nanotopographical control over a stainless steel surface via an electrophoretic deposition of colloidal amphiphilic chitosan for preferential growth, proliferation or migration of vascular smooth muscle cells (VSMCs) and human umbilical vein endothelial cells (HUVECs). Atomic force microscopy revealed that the colloidal surface exhibited a deposition time-dependent nanotopographical evolution, wherein two different nanotopographic textures indexed by 'kurtosis' (R-kur) value were easily designed, which were termed as 'sharp' (i.e. high peak-to-valley texture) surface and 'flat' (i.e. low peak-to-valley texture) surface. Cellular behaviour of VSMCs and HUVECs on both surfaces demonstrated topographically dependent morphogenesis, adherent responses and biochemical properties in comparison with bare stainless steel. The formation of a biofunctionalized surface upon a facile colloidal chitosan deposition envisions the potential application towards numerous biomedical devices, and this is especially promising for cardiovascular stents wherein a new surface with optimized texture can be designed and is expected to create an advantageous environment to stimulate HUVEC growth for improved healing performance.
Epidermal grafting for leukoderma resulting from 1064-nm quality-switched neodymium-doped yttrium aluminium garnet laser toning
(2018-12-01)
Wang, Yen-Jen
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Chang, Chang-Cheng
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影像與生醫光電研究所
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Institute of Imaging and Biomedical Photonics
Leukoderma secondary to Q-switched 1064-nm neodymium-doped yttrium aluminium garnet laser is usually refractory to treatment. The pathogenesis was cumulative phototoxic damage to melanocytes and eventually resulted in melanocytopenia. Wood's light or UV imaging can help observe early leukoderma before it becomes apparent clinically and determine the degree of melanocytopenia before conducting a biopsy. NB-UVB phototherapy and 308-nm excimer laser can potentially worsen the pre-existing melasma lesions and may not be effective if the lesions have already become melanocytopenic. Epidermal grafting can replenish the hypopigmented area with melanocytes without worsening melasma.
Forming of Demethoxycurcumin Nanocrystallite-Chitosan Nanocarrier for Controlled Low Dose Cellular Release for Inhibition of the Migration of Vascular Smooth Muscle Cells
(2012-08-01)
Wang, Yen-Jen
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Lin, Hui-Yi
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Wu, Chieh-Hsi
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Liu, Dean-Mo
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材料科學與工程學系
"We report an efficient therapeutic approach to inhibit the migration and growth of vascular smooth muscle cells (VSMCs) via a low-dose sustained elution of a water-insoluble drug, demethoxycurcumin (DMC), through a self-assembled amphiphilic carbomethyl-hexanol chitosan (CHC) nanomatrix. Manipulating the cellular internalization and controlled cytotoxic effect of DMC-CHC nanoparticles over the VSMCs was elucidated. The DMC-CHC nanoparticles, which were systematically characterized in terms of structural morphology, surface potential, encapsulation efficiency, and DMC nanocrystallite distribution, exhibited rapid cellular uptake efficiency and considerably improved cytotoxic potency by 2.8 times compared to the free DMC. Under a cytotoxic evaluation, an improved antiproliferative effect and effective inhibition of VSMC migration as a result of highly efficient intracellular delivery of the encapsulated DMC in comparison to free DMC was achieved, which also was confirmed with a subsequent protein analysis. Cellular drug release and distribution of DMC after internalization into VSMCs was experimentally determined. This work may open a potential intracellular medicinal strategy with improved biological and therapeutic efficacy using the DMC-CHC nanoparticles illustrated in this work."
Magnolol-Loaded Core-Shell Hydrogel Nanoparticles: Drug Release, Intracellular Uptake, and Controlled Cytotoxicity for the Inhibition of Migration of Vascular Smooth Muscle Cells
(2011-11-01)
Wang, Yen-Jen
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Chien, Yin-Chih
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Wu, Chieh-Hsi
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Liu, Dean-Mo
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材料科學與工程學系
Encapsulation and release behavior of a water-insoluble drug, magnolol, using a core shell polysaccharide-based nanoparticle, manipulating the cellular internalization and controlled cytotoidc effect of magnolol-loaded nanoparticles over the A10 vascular smooth muscle cells (VSMCs) was reported. A magnolol-polyvinylpyrrolidone (PVP) core phase was prepared, followed encapsulating by an amphiphilic carboxymethyl-hexanoyi chitosan (CHC) shell to form a magnolol-loaded core-shell hydrogel nanoparticles (termed magnolol-CHC nanoparticles). The resulting magnolol-CHC nanopartides were employed for evaluation of drug release and controlled cytotoxic inhibition of VSMCs migration in vitro. A sustained release of the magnolol from the nanoparticles was determined. The magnolol-CHC nanoparticles exhibited outstanding cellular uptake efficiency, and under a cytotoxic evaluation, an increased antiproliferative effect and effective inhibition of VSMC migration as a result of efficient intracellular delivery of the encapsulated magnolol in comparison to free magnolol was achieved. We then envision a potential intracellular medication strategy with improved biological and therapeutic efficacy using the magnolol-CHC nanoparticles illustrated in this work.
Re: Epidermal skin grafting in vitiligo: a pilot study
(2017-12-01)
Cheng, Kun-Lin
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Chang, Chang-Cheng
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Wang, Yen-Jen
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影像與生醫光電研究所
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Institute of Imaging and Biomedical Photonics
Surface characteristics and biofunctionality of a novel high-performance, hydrophilic Jeffamine-added fluoro-containing polyimide for biomedical applications
(2015-01-24)
Lo, Teng-Yuan
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Wang, Yen-Jen
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Liu, Dean-Mo
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Whang, Wha-Tzong
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材料科學與工程學系
A brand-new class of Jeffamine-modified fluorocontaining polyimide (6FPI-J(x) series, where x ranges from 10, 20, and 30 % by weight) was developed in this study. The existing pristine fluoro-containing polyimide (6FPI) is a flexible and high-performance polymer with low surface energy for advanced engineering applications. Although it has been considered a promising biomaterial for its good blood compatibility, it has known to be toxic to normal cells. Here, we modified 6FPI [with -C (CF3)(2)-group on backbone] with a hydrophilic diamine monomer, Jeffamine, denoted as 6FPI-J(x), where x is the molar percentage of the total diamines. The newly synthesized 6FPI-J(x) series was systematically characterized in terms of surface properties included surface texture, chemistry, potential, and charging. Besides, the 6FPI-J(x) copolymer exhibited good mechanical and stability as pristine 6FPI. With the addition of Jeffamine (x=10 %), 6FPI-J(10) displayed considerably improved blood and cell compatibility compared to 6FPI, which was explainable as a combined effect of morphological texture and chemical environment of resulting surface. The new class of 6FPI-J(x) exhibited excellent solubility toward a number of organic solvents, which rendered the 6FPI-J(10) a great potential candidate as a biocompatible coating for implantable medical devices and also for potential therapeutic applications.
The use of polymer-based nanoparticles and nanostructured materials in treatment and diagnosis of cardiovascular diseases: Recent advances and emerging designs
(2016-06)
Wang, Yen-Jen
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Larsson, Mikael
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Huang, Wei-Ting
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Chiou, Shih-Hwa
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Nicholls, Stephen J.
This review summarizes important advances in polymer-based nanotechnologies for the treatment and diagnosis of cardiovascular diseases, focusing on nanoparticles and nanostructured materials/devices. The current state of the art and design parameters are discussed with the aim of providing a source of information that can aid in the development of new treatments by bridging between materials development, preclinical, and clinical trials. This is highly relevant as cardiovascular diseases remain a leading cause of death worldwide and as current treatments burden the healthcare systems with great costs. Different strategies, from targeting theranostic nanocarriers, to dual-drug depot systems, injectable cell scaffolds, and LDL acceptors are treated. The review ends with a concluding outlook on the ossibilities and challenges presented to polymer-based nanotechnologies in cardiovascular disease therapy. (c) 2016 Elsevier Ltd. All rights reserved.
Wood's lamp for vitiligo disease stability and early recognition of initiative pigmentation after epidermal grafting
(2017-12-01)
Wang, Yen-Jen
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Chang, Chang-Cheng
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Cheng, Kun-Lin
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影像與生醫光電研究所
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Institute of Imaging and Biomedical Photonics
The prerequisite for a successful vitiligo epidermal grafting surgery is the stable status of the disease. We used Wood's lamp to assess vitiligo activity to determine the disease stability, surgical grafting timing and the early recognition of re-pigmentation after grafting. Amelanotic lesions with sharply demarcated borders are typically stable and are good candidates for grafting. The re-pigmentation was first recognised under Wood's lamp as hypochromic islands, which progressed to normally pigmented islands. For patients more prone to relapse, follow up with Wood's lamp also provides more accurate surveillance.