Browsing by Author "Chen, Chung-Hsuan"

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A quadrupole ion trap mass spectrometer for dry microparticle analysis
(2019-09-21)
Ozdemir, Abdil
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Lin, Jung-Lee
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Gulfen, Mustafa
;
Hsiao, Chun-Jen
;
Chen, Chung-Hsuan
In this work, we report a new design of a charge detection quadrupole ion trap mass spectrometer (QIT-MS) for the analysis of micro-sized dry inorganic and bioparticles including red blood cells (RBCs) and different sizes of MCF-7 breast cancer cells. The developed method is one of the fastest methods to measure the mass of micro-sized particles. This system allows the online analysis of various micro-sized particles up to 1 x 10(17) Da. The calibration of the mass spectrometer has been done by using different sizes of polystyrene (PS) particles (2-15 mu m). The measured masses of RBCs were around 1.8 x 10(13) Da and MCF-7 cancer cells were between 1 x 10(14) and 4 x 10(14) Da. The calculated mass distribution profiles of the particles and cells were given as histogram profiles. The statistical data were summarized after Gaussian type fitting to the experimental histogram profiles. The new method gives very promising results for the analysis of particles and has very broad application.
Ash2l interacts with Oct4-stemness circuitry to promote super-enhancer-driven pluripotency network
(2019-11-04)
Tsai, Ping-Hsing
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Chien, Yueh
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Wang, Mong-Lien
;
Hsu, Chih-Hung
;
Laurent, Benoit
Pluripotency and cell fates can be modulated through the regulation of super-enhancers; however, the underlying mechanisms are unclear. Here, we showed a novel mechanism in which Ash2l directly binds to super-enhancers of several stemness genes to regulate pluripotency and self-renewal in pluripotent stem cells. Ash2l recruits Oct4/Sox2/Nanog (OSN) to form Ash2l/OSN complex at the super-enhancers of Jarid2, Nanog, Sox2 and Oct4, and further drives enhancer activation, upregulation of stemness genes, and maintains the pluripotent circuitry. Ash2l knockdown abrogates the OSN recruitment to all super-enhancers and further hinders the enhancer activation. In addition, CRISPRi/dCas9-mediated blocking of Ash2l-binding motifs at these super-enhancers also prevents OSN recruitment and enhancer activation, validating that Ash2l directly binds to super-enhancers and initiates the pluripotency network. Transfection of Ash2l with W118A mutation to disrupt Ash2l-Oct4 interaction fails to rescue Ash2l-driven enhancer activation and pluripotent gene upregulation in Ash2l-depleted pluripotent stem cells. Together, our data demonstrated Ash2l formed an enhancer-bound Ash2l/OSN complex that can drive enhancer activation, govern pluripotency network and stemness circuitry.
DIFFERENTIATION OF NEURAL STEM/PROGENITOR CELLS USING LOW-INTENSITY ULTRASOUND
(2014-09-01)
Lee, I-Chi
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Lo, Tsu-Lin
;
Young, Tai-Horng
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Li, Yi-Chen
;
Chen, Nelson G.
Herein, we report the evaluation of apoptosis, cell differentiation, neurite outgrowth and differentiation of neural stem/progenitor cells (NSPCs) in response to low-intensity ultrasound (LIUS) exposure. NSPCs were cultured under different conditions, with and without LIUS exposure, to evaluate the single and complex effects of LIUS. A lactic dehydrogenase assay revealed that the cell viability of NSPCs was maintained with LIUS exposure at an intensity range from 100 to 500 mW/cm(2). Additionally, in comparison with no LIUS exposure, the cell survival rate was improved with the combination of medium supplemented with nerve growth factor and LIUS exposure. Our results indicate that LIUS exposure promoted NSPC attachment and differentiation on a glass substrate. Neurite outgrowth assays revealed the generation of longer, thicker neurites after LIUS exposure. Furthermore, LIUS stimulation substantially increased the percentage of differentiating neural cells in NSPCs treated with nerve growth factor in comparison with the unstimulated group. The high percentage of differentiated neural cells indicated that LIUS induced neuronal networks denser than those observed in the unstimulated groups. Furthermore, the release of nitric oxide, an important small-molecule neurotransmitter, was significantly upregulated after LIUS exposure. It is therefore reasonable to suggest that LIUS promotes the differentiation of NSPCs into neural cells, induces neurite outgrowth and regulates nitric oxide production; thus, LIUS may be a potential candidate for NSPC induction and neural cell therapy. (E-mail: iclee@mail.cgu.edu.tw or yingchih@gate.sinica.edu.tw) (C) 2014 World Federation for Ultrasound in Medicine & Biology.
ESI MS for Microsized Bioparticles
(2017-12-19)
Ozdemir, Abdil
;
Lin, Jung-Lee
;
Gulfen, Mustafa
;
Lai, Szu-Hsueh
;
Hsiao, Chun-Jen
An ESI ion trap mass spectrometer was designed for high-throughput and rapid mass analysis of large bioparticles. Mass calibration of the instrument was performed using commercially available polystyrene (PS) microparticles with a size comparable to cancer cells. Different sites of MCF-7 breast cancer cells (8 to 15 mu m) were used in this study. The masses of different cancer cells were measured. This system allows for the analysis of all types of particles.
Integrated multiple multi-photon imaging and Raman spectroscopy for characterizing structure-constituent correlation of tissues
(2008-10-13)
Jhan, Jhen-Wei
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Chang, Wei-Tien
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Chen, Hung-Che
;
Lee, Yu-Tsung
;
Wu, Ming-Fang
Histopathological imaging of tissues often requires extensive sample preparation including fixation and staining in order to highlight characteristic alterations associated with diseases. Herein, we report an integrated spectro-microscopy approach based on a combination of multimodal multi-photon imaging and Raman micro-spectroscopy and demonstrate label-free characterization of the structure-constituent correlation of porcine skin. The multi-modal imaging allows the visualization of dermatological features whereas Raman micro-spectroscopy enables the identification of their 'molecular fingerprints'. By obtaining both structural and molecular-level information of tissue constituents, this integrated approach can offer new insight into the patho-physiological status of tissues. (c) 2008 Optical Society of America
Interleukin-18 deteriorates Fabry cardiomyopathy and contributes to the development of left ventricular hypertrophy in Fabry patients with GLA IVS4+919 G>A mutation
(2016-12-27)
Chien, Yueh
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Chien, Chian-Shiu
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Chiang, Huai-Chih
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Huang, Wei-Lin
;
Chou, Shih-Jie
Rationale: A high incidence of GLA IVS4+919 G>A mutation in patients with Fabry disease of the later-onset cardiac phenotype, has been reported in Taiwan. However, suitable biomarkers or potential therapeutic surrogates for Fabry cardiomyopathy (FC) in such patients under enzyme replacement treatment (ERT) remain unknown. Objective: Using FC patients carrying IVS4+919 G>A mutation, we constructed an induced pluripotent stem cell (iPSC)-based disease model to investigate the pathogenetic biomarkers and potential therapeutic targets in ERT-treated FC. Results and methods: The iPSC-differentiated cardiomyocytes derived from FC-patients (FC-iPSC-CMs) carried IVS4+919 G>A mutation recapitulating FC characteristics, including low a-galactosidase A enzyme activity, cellular hypertrophy, and massive globotriaosylceramide accumulation. Microarray analysis revealed that interleukin-18 (IL-18), a pleiotropic cytokine involved in various myocardial diseases, was the most highly upregulated marker in FC-iPSC-CMs. Meanwhile, IL-18 levels were found to be significantly elevated in the culture media of FC-iPSC-CMs and patients\' sera. Notably, the serum IL-18 levels were highly paralleled with the progression of left ventricular hypertrophy in Fabry patients receiving ERT. Finally, using FC-iPSC-CMs as in vitro FC model, neutralization of IL-18 with specific antibodies combined with ERT synergistically reduced the secretion of IL-18 and the progression of cardiomyocyte hypertrophy in FC-iPSC-CMs. Conclusion: Our data demonstrated that cardiac IL-18 and circulating IL-18 are involved in the pathogenesis of FC and LVH. IL-18 may be a novel marker for evaluating ERT efficacy, and targeting IL-18 might be a potential adjunctive therapy combined with ERT for the treatment of advanced cardiomyopathy in FC patients with IVS4+919 G>A mutation.
Investigation of nanoparticle-assisted ultrasound therapy for treating implanted breast tumors in mice
(2017-01-01)
Kosheleva, Olga
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Lai, Tsung-Ching
;
Chan, Yung-Chieh
;
Hsiao, Michael
;
Ng, Shok-Li
The presence of nanoparticles within an ultrasonic field has been previously shown to cause ultrasound to preferentially destroy cancerous cells over corresponding normal cells. Such treatment, termed nanoparticle-assisted ultrasound therapy (NAUT), has now been applied to subcutaneously implanted tumors in mice. Xenografted tumors were exposed to therapeutic ultrasound, with and without intratumoral injections of nanoparticles over a period of 4 weeks. Post-treatment, tumors that received nanoparticle injections were found to be substantially smaller than controls, suggesting that nanoparticle presence significantly increases the efficacy of ultrasonic treatment of solid tumors.
Selective killing of cancer cells by nanoparticle-assisted ultrasound
(2016-06-14)
Kosheleva, Olga K.
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Lai, Tsung-Ching
;
Chen, Nelson G.
;
Hsiao, Michael
;
Chen, Chung-Hsuan
Background: Intense ultrasound, such as that used for tumor ablation, does not differentiate between cancerous and normal cells. A method combining ultrasound and biocompatible gold or magnetic nanoparticles (NPs) was developed under in vitro conditions using human breast and lung epithelial cells, which causes ultrasound to preferentially destroy cancerous cells. Results: Co-cultures of BEAS-2B normal lung cells and A549 cancerous lung cells labeled with green and red fluorescent proteins, respectively, were treated with focused ultrasound beams with the addition of gold and magnetic nanoparticles. There were significantly more necrotic A549 cells than BEAS-2 cells when gold nanoparticles were added to the culture medium [(50.6 +/- 15.1) vs. (7.4 +/- 2.9) %, respectively, P < 0.01]. This selective damage to cancer cells was also observed for MDA-MB231 breast cancer cells relative to MCF-10A normal breast cells after treatment with magnetic nanoparticles. Conclusions: The data obtained for different cell lines indicate that nanoparticle-assisted ultrasound therapy (NAUT) could be an effective new tool for cancer-specific treatment and could potentially be combined with conventional methods of cancer diagnosis and therapy to further increase the overall cancer cure rate.