Browsing by Author "Tseng, Shin-Hua"

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Development of a Growth- Hormone- Conjugated Nanodiamond Complex for Cancer Therapy
(2014-05-01)
Chu, Hsueh-Liang
;
Chen, Hung-Wei
;
Tseng, Shin-Hua
;
Hsu, Ming-Hua
;
Ho, Li-Ping
It is highly desirable to develop a therapeutic, observable nanoparticle complex for specific targeting in cancer therapy. Growth hormone (GH) and its antagonists have been explored as cancer cell-targeting molecules for both imaging and therapeutic applications. In this study, a low toxicity, biocompatible, therapeutic, and observable GH-nanoparticle complex for specifically targeting growth hormone receptor (GHR) in cancer cells was synthesized by conjugating GH with green fluorescence protein and carboxylated nanodiamond. Moreover, we have shown that this complex can be triggered by laser irradiation to create a nanoblast and induce cell death in the A549 non-small-cell lung cancer cell line via the apoptotic pathway. This laser-mediated, cancer-targeting platform can be widely used in cancer therapy.
DNA Mismatch Detection by Metal Ion Enhanced Impedance Analysis
(2009-10-01)
Jangjian, Peng-Chung
;
Liu, Tzeng-Feng
;
Tsai, Chuan-Mei
;
Li, Mei-Yi
;
Tsai, Ming-Shih
Conventional diagnoses of genetic mutation and disease depend on the analysis of DNA sequences. However, mismatches in the DNA sequences are difficult to detect using traditional sequencing. Doping metal ions, such as nickel, into the short DNA (28 mer similar to 30 mer), markedly reduces its electrical resistance, which is measured by electrical impedance analysis. The change in resistance that is caused by a mismatched base-pair in short DNA can also be monitored by this approach. In this study, the resistance increased exponentially with the number of mismatched base-pairs. Accordingly, an intuitive and direct method for evaluating the number of DNA mismatches can possibly be developed.
Human haptoglobin phenotypes and concentration determination by nanogold-enhanced electrochemical impedance spectroscopy
(2011-05-17)
Cheng, Tsai-Mu
;
Lee, Tzu-Cheng
;
Tseng, Shin-Hua
;
Chu, Hsueh-Liang
;
Pan, Ju-Pin
Haptoglobin (Hp) is an acute phase protein that binds free hemoglobin (Hb), preventing Hb-induced oxidative damage in the vascular system. There are three phenotypes in human Hp, whose heterogeneous polymorphic structures and varying concentrations in plasma have been attributed to the cause of diseases and outcome of clinical treatments. Different phenotypes of Hp may be composed of the same subunits but different copy numbers, rendering their determination difficult by a single procedure. In this study, we have developed a simple, fast, reliable and sensitive method, using label-free nanogold-modified bioprobes coupled with self-development electrochemical impedance spectroscopy (EIS). By this method, probe surface charge transfer resistance is detected. The relative charge transfer resistance ratios for Hp 1-1, Hp 2-1 and Hp 2-2 were characterized. We were able to determine protein size difference within 3 nm, and the linear region of the calibration curve for Hp levels in the range of 90 pg ml(-1) and 90 mu g ml(-1) (similar to 1 fM to 1 pM). We surmise that similar approaches can be used to investigate protein polymorphism and altered protein-protein interaction associated with diseases.
Ni(2+)-Enhanced Charge Transport via pi-pi Stacking Corridor in Metallic DNA
(2011-02-16)
Tseng, Shin-Hua
;
JangJian, Peng-Chung
;
Tsai, Chuan-Mei
;
Cheng, Tsai-Mu
;
Chu, Hsueh-Liang
The mechanism underlying DNA charge transport is intriguing. However, poor conductivity of DNA makes it difficult to detect DNA charge transport. Metallic DNA (M-DNA) has better conducting properties than native DNA. Ni(2+) may chelate in DNA and thus enhance DNA conductivity. On the basis of this finding, it is possible to reveal the mechanisms underlying DNA charge transport. The conductivity of various Ni-DNA species such as single-stranded, full complement, or mismatched sequence molecules was systematically tested with ultraviolet absorption and electrical or chemical methods. The results showed that the conductivity of single-stranded Ni-DNA (Ni-ssDNA) was similar to that of a native DNA duplex. Moreover, the resistance of Ni-DNA with a single basepair mismatch was significantly higher than that of fully complementary Ni-DNA duplexes. The resistance also increased exponentially as the number of mismatched basepairs increased linearly after the tunneling current behavior predicted by the Simmons model. In conclusion, the charges in Ni(2+)-doped DNA are transported through the Ni(2+)-mediated pi-pi stacking corridor. Furthermore, Ni-DNA acts as a conducting wire and exhibits a tunneling barrier when basepair mismatches occur. This property may be useful in detecting single basepair mismatches.
Ni2+-Enhanced Charge Transport via pi-pi Stacking Corridor in Metallic DNA
(2011-02-16)
Tseng, Shin-Hua
;
JangJian, Peng-Chung
;
Tsai, Chuan-Mei
;
Cheng, Tsai-Mu
;
Chu, Hsueh-Liang
The mechanism underlying DNA charge transport is intriguing. However, poor conductivity of DNA makes it difficult to detect DNA charge transport. Metallic DNA (M-DNA) has better conducting properties than native DNA. Ni2+ may chelate in DNA and thus enhance DNA conductivity. On the basis of this finding, it is possible to reveal the mechanisms underlying DNA charge transport. The conductivity of various Ni-DNA species such as single-stranded, full complement, or mismatched sequence molecules was systematically tested with ultraviolet absorption and electrical or chemical methods. The results showed that the conductivity of single-stranded Ni-DNA (Ni-ssDNA) was similar to that of a native DNA duplex. Moreover, the resistance of Ni-DNA with a single basepair mismatch was significantly higher than that of fully complementary Ni-DNA duplexes. The resistance also increased exponentially as the number of mismatched basepairs increased linearly after the tunneling current behavior predicted by the Simmons model. In conclusion, the charges in Ni2+-doped DNA are transported through the Ni2+-mediated pi-pi stacking corridor. Furthermore, Ni-DNA acts as a conducting wire and exhibits a tunneling barrier when basepair mismatches occur. This property may be useful in detecting single basepair mismatches.
Rapid Detection and Quantification of Enterovirus 71 by Electrochemical Impedance Spectroscopy
(2012-01-31)
Li, Hsing-Yuan
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Yang, Jyh-Yuan
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Cheng, Tsia-Mu
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Tseng, Shin-Hua
;
Chang, Chia-Ching
Single domain antibody against carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) inhibits proliferation, migration, invasion and angiogenesis of pancreatic cancer cells
(2014-03-01)
Cheng, Tsai-Mu
;
Murad, Yanal M.
;
Chang, Chia-Ching
;
Yang, Ming-Chi
;
Baral, Toya Nath
Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is over-expressed in pancreatic cancer cells, and it is associated with the progression of pancreatic cancer. We tested a single domain antibody (sdAb) targeting CEACAM6, 2A3, which was isolated previously from a llama immune library, and an Fc conjugated version of this sdAb, to determine how they affect the pancreatic cancer cell line BxPC3. We also compared the effects of the antibodies to gemcitabine. Gemcitabine and 2A3 slowed down cancer cell proliferation. However, only 2A3 retarded cancer cell invasion, angiogenesis within the cancer mass and BxPC3 cell MMP-9 activity, three features important for tumour growth and metas- tasis. The IC(50)s for 2A3, 2A3-Fc and gemcitabine were determined as 6.5 mu M, 8 mu M and 12 nM, respectively. While the 2A3 antibody inhibited MMP-9 activity by 33% compared to non-treated control cells, gemcitabine failed to inhibit MMP-9 activity. Moreover, 2A3 and 2A3-Fc inhibited invasion of BxPC3 by 73% compared to non-treated cells. When conditioned media that were produced using 2A3- or 2A3-Fc-treated BxPC3 cells were used in a capillary formation assay, the capillary length was reduced by 21% and 49%, respectively. Therefore 2A3 is an ideal candidate for treating tumours that over-express CEACAM6. (C) 2012 Elsevier Ltd. All rights reserved.
Thermal stability and folding kinetics analysis of disordered protein, securin
(2014-03-01)
Chu, Hsueh-Liang
;
Chen, Tzu-Hsuan
;
Wu, Chang-You
;
Yang, Yao-Chen
;
Tseng, Shin-Hua
Lacking a stable tertiary structure, intrinsically disordered proteins (IDPs) possess particular functions in cell regulation, signaling, and controlling pathways. The study of their unique structural features, thermal stabilities, and folding kinetics is intriguing. In this study, an identified IDP, securin, was used as a model protein. By using a quasi-static five-step (on-path) folding process, the function of securin was restored and analyzed by isothermal titration calorimetry. Fluorescence spectroscopy and particle size analysis indicated that securin possessed a compact hydrophobic core and particle size. The glass transition of securin was characterized using differential scanning microcalorimetry. Furthermore, the folding/unfolding rates (k(obs)) of securin were undetectable, implying that the folding/unfolding rate is very fast and that the conformation of securin is sensitive to solvent environmental change. Therefore, securin may fold properly under specific physiological conditions. In summary, the thermal glass transition behavior and undetectable k(obs) of folding/unfolding reactions may be two of the indices of IDP.
ULTRA SENSITIVE DETECTION OF ENETEROVIRUS 71 BY MODIFIED ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY
(2010)
Tseng, Shin-Hua
;
Tseng, Dion T.
;
Lee, Tzu-Cheng
;
Cheng, Tsai-Mu
;
Yang, Jyh-Yuan
The enterovirus 71 (EV71) has threatened Taiwan for more than ten years. Since traditional diagnostic methods are complicated, time consuming, and high-qualified personnel required. Therefore, a new detection process is highly desired. In this study, a high sensitive PC-based electrochemical analyzing system with a functionalized nano-gold modified immunological electrode are developed to detect EV71. Immobilizing specific EV71 polyclone antibodies, which is developed by center for disease control (CDC) Taiwan, onto nano gold of sensing electrode, the affinity interaction of the immobilized antibody with the specific antigen is identified quickly by electrochemical impedance spectrum (EIS) within 20 minutes. The detection limit of this EIS analysis was as low as 50 copy per ml (similar to sub-atto molar). In summary, a biosensor and analyzing system based on EIS has been developed to identify EV71 with efficiency, high sensitivity and specificity.