Browsing by Author "Cheng, Tsai-Mu"

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Development of a Growth- Hormone- Conjugated Nanodiamond Complex for Cancer Therapy
(2014-05-01)
Chu, Hsueh-Liang
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Chen, Hung-Wei
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Tseng, Shin-Hua
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Hsu, Ming-Hua
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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
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Liu, Tzeng-Feng
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Tsai, Chuan-Mei
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Li, Mei-Yi
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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.
Folding and Characterization of Intrinsically Disordered Protein Human Cyclin I (Ccni)
(2012-01-31)
Chu, Hsueh-Liang
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Cheng, Tsai-Mu
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Li, Hsing-Yuan
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Chang, Chia-Ching
;
交大名義發表
Gel electrophoresis of polyphenol oxidase with instant identification by in situ blotting
(2007-04-15)
Cheng, Tsai-Mu
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Huang, Pei-Chen
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Pan, Ju-Pin
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Lin, Kuan-Yu
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Mao, Simon J. T.
Polyphenol oxidase (PPO) or tyrosinase is an important and ubiquitous enzyme responsible for browning in plants and melanization in animals. The molecular size of the plant PPO is varied among the species and its activity can be enhanced by a variety of anionic detergents. In the present study, we developed a simple method for the first-step identification of PPO in fruit and vegetable extracts. First, 3 mm chromatographic paper was immersed in 0.5% (w/v) catechol solution as an immobilized PPO substrate. After running the extract with 10% sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SIDS-PAGE), one side of the glass plate was removed. The plate was immediately laid on top of the dried catechol-paper. A dark-brown band corresponding to PPO was visualized within I min and was further confirmed by a conventional Western blot using an antibody prepared against mushroom PPO. It also reveals that some vegetation (such as tomato, radish, and oriental melon) with low or no detectable activity in a conventional enzyme assay actually possessed marked levels of PPO activity when assessed by PAGE-blot. We propose that an inhibitor is associated with PPO in some plants; the inhibitor, however, is dissociated during the electrophoresis. Therefore, in addition to identify the molecular form of PPO, the present technique may explore the existence of PPO inhibitor(s) in plants. The detail of the method with respect to its relevance for searching a natural PPO inhibitor is described and discussed. (c) 2006 Elsevier B.V. All rights reserved.
Haemoglobin-induced oxidative stress is associated with both endogenous peroxidase activity and H(2)O(2) generation from polyunsaturated fatty acids
(2011-03-01)
Cheng, Tsai-Mu
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Mao, Simon J. T.
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Lai, Shiau-Ting
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Chang, Chia-Ching
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Yang, Ming-Chi
Patients with increased haemolytic haemoglobin (Hb) have 10-20-times greater incidence of cardiovascular mortality. The objective of this study was to evaluate the role of Hb peroxidase activity in LDL oxidation. The role of Hb in lipid peroxidation, H(2)O(2) generation and intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) was assessed using NaN(3), a peroxidase inhibitor, catalase, a H(2)O(2) decomposing enzyme and human umbilical vein endothelial cells (HUVECs), respectively. Hb induced H(2)O(2) production by reacting with LDL, linoleate and cell membrane lipid extracts. Hb-induced LDL oxidation was inhibited by NaN(3) and catalase. Furthermore, Hb stimulated ICAM-1 and VCAM-1 expression, which was inhibited by the antioxidant, probucol. Thus, the present study suggests that the peroxidase activity of Hb produces atherogenic, oxidized LDL and oxidized polyunsaturated fatty acids (PUFAs) in the cell membrane and reactive oxygen species (ROS) formation mediated Hb-induced ICAM-1 and VCAM-1 expression.
Haemoglobin-induced oxidative stress is associated with both endogenous peroxidase activity and H2O2 generation from polyunsaturated fatty acids
(2011-03-01)
Cheng, Tsai-Mu
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Mao, Simon J. T.
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Lai, Shiau-Ting
;
Chang, Chia-Ching
;
Yang, Ming-Chi
Patients with increased haemolytic haemoglobin (Hb) have 10-20-times greater incidence of cardiovascular mortality. The objective of this study was to evaluate the role of Hb peroxidase activity in LDL oxidation. The role of Hb in lipid peroxidation, H2O2 generation and intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) was assessed using NaN3, a peroxidase inhibitor, catalase, a H2O2 decomposing enzyme and human umbilical vein endothelial cells (HUVECs), respectively. Hb induced H2O2 production by reacting with LDL, linoleate and cell membrane lipid extracts. Hb-induced LDL oxidation was inhibited by NaN3 and catalase. Furthermore, Hb stimulated ICAM-1 and VCAM-1 expression, which was inhibited by the antioxidant, probucol. Thus, the present study suggests that the peroxidase activity of Hb produces atherogenic, oxidized LDL and oxidized polyunsaturated fatty acids (PUFAs) in the cell membrane and reactive oxygen species (ROS) formation mediated Hb-induced ICAM-1 and VCAM-1 expression.
Haptoglobin phenotypes and plasma haptoglobin levels in patients with abdominal aortic aneurysm
(2011-05-01)
Pan, Ju-Pin
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Cheng, Tsai-Mu
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Shih, Chun-Che
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Chiang, Shu-Chiung
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Chou, Shiu-Chin
Objective: Inflammation is associated with the disruption of the aortic media and appears to play a fundamental role in the progression and development of abdominal aortic aneurysm (AAA). Haptoglobin (Hp) is a genetically determined acute phase protein, the synthesis of which is increased during inflammation. This study was designed to investigate both phenotype and plasma levels of Hp in patients with AAA. Methods: Patients with documented AAA who were admitted for elective open repair operation or endograft stem implantation, and non-AAA subjects admitted for coronary arteriography, but found to have normal or insignificant coronary artery disease, were included in the study. Plasma Hp levels were determined using a standard specific enzyme-linked immunosorbent assay, while Hp phenotype was determined by native polyacrylamide gel electrophoresis. Total cholesterol, high density lipoprotein, low density lipoprotein, and triglyceride levels were analyzed enzymatically, and C-reactive protein was analyzed by immunochemistry. Results: Forty-five patients with AAA and 49 non-AAA subjects were included. The Hp 2-2 phenotype was more predominant in AAA patients compared with non-AAA subjects, but this difference was not significant (67% vs 47%; P = .141), while plasma Hp concentrations were significantly higher in AAA patients (237 +/- 144 vs 163 +/- 86 ng/mL; P = .024). Further analysis revealed that plasma Hp concentrations were significantly higher in AAA patients with the 2-2 phenotype compared with corresponding non-AAA subjects (238 +/- 144 vs 163 +/- 86 ng/mL;P = .024). Conclusions: Our findings suggest that plasma Hp concentrations are elevated in patients with AAA, particularly those with the Hp 2-2 phenotype. (J Vasc Surg 2011;53:1189-94.)
Hemoglobin induced oxidative stress is associated with both endogenous peroxidase activity and H2O2 generation from polyunsaturated fatty acids
(2010-04-01)
Cheng, Tsai-Mu
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Pan, Ju-Pin
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Chen, Hong-Wei
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Chang, Yi-Chun
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Chang, Chia-Ching
Human haptoglobin phenotypes and concentration determination by nanogold-enhanced electrochemical impedance spectroscopy
(2011-05-17)
Cheng, Tsai-Mu
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Lee, Tzu-Cheng
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Tseng, Shin-Hua
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Chu, Hsueh-Liang
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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.
Immunochemical property of human haptoglobin phenotypes: Determination of plasma haptoglobin using type-matched standards
(2007-09-01)
Cheng, Tsai-Mu
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Pan, Ju-Pin
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Lai, Shiau-Ting
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Kao, Li-Pin
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Lin, Hong-Huel
Objectives: Haptoglobin (Hp) phenotypes 1-1, 2-1, and 2-2 are associated with inflammatory diseases. Since their biochemical structures are rather heterogeneous, it is necessary to accurately determine the plasma Hp levels. Design and methods: Immunodiffusion, immunoturbidimetric, and noncompetitive ELISA were conducted to determine the differences in immunoreactivity among Hp phenotypes and to verify that such difference may significantly affect the outcome of Hp determinations. A novel ELISA using phenotype-matched calibrators was performed to compared with a commercial GenWay ELISA kit using a single calibrator in normal healthy males. Results: In immunodiffusion and immunoturbidimetric assays, the immumoreactivity of Hp 1-1 was markedly higher than 2-1 and 2-2, while an opposite result was observed using an ELISA. The latter was primarily due to the repeated antigenic epitopes in polymeric 2-1 and 2-2. Thus, Hp levels could be significantly over- or underestimated depending on the method. An accurate ELISA could be achieved when using each type-specific Hp calibrator matched to each type subject. We show the mean levels of Hp 1-1 subjects (n= 16; 184 +/- 42 mg/dL) to be significantly and differentially greater than 2-1 (n=28; 153 +/- 55 mg/dL) (p < 0.05) and 2-2 (n=24; 93 +/- 54 mg/dL) (p < 0.01) subjects. Conclusions: Due to the diverse immunochemical structure among the Hp types, phenotyping should be performed in all the patients and a type-matched Hp calibrator should be used in clinical Hp determination. (c) 2007 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.
Molecular Mechanism of Nanodiamonds Attacking Cancer Cell
(2010-04-01)
Chen, Hong-Wei
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Cheng, Tsai-Mu
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Chu, Hsueh-Liang
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Chang, Chia-Ching
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生物科技學系
Ni(2+)-Enhanced Charge Transport via pi-pi Stacking Corridor in Metallic DNA
(2011-02-16)
Tseng, Shin-Hua
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JangJian, Peng-Chung
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Tsai, Chuan-Mei
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Cheng, Tsai-Mu
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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
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JangJian, Peng-Chung
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Tsai, Chuan-Mei
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Cheng, Tsai-Mu
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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 and highly sensitive detection of Enterovirus 71 by using nanogold-enhanced electrochemical impedance spectroscopy
(2013-07-19)
Li, Hsing-Yuan
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Tseng, Shing-Hua
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Cheng, Tsai-Mu
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Chu, Hsueh-Liang
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Lu, Yu-Ning
Enterovirus 71 (EV71) infection is an emerging infectious disease causing neurological complications and/or death within two to three days after the development of fever and rash. A low viral titre in clinical specimens makes the detection of EV71 difficult. Conventional approaches for detecting EV71 are time consuming, poorly sensitive, or complicated, and cannot be used effectively for clinical diagnosis. Furthermore, EV71 and Coxsackie virus A16 (CA16) may cross react in conventional assays. Therefore, a rapid, highly sensitive, specific, and user-friendly test is needed. We developed an EV71-specific nanogold-modified working electrode for electrochemical impedance spectroscopy in the detection of EV71. Our results show that EV71 can be distinguished from CA16, Herpes simplex virus, and lysozyme, with the modified nanogold electrode being able to detect EV71 in concentrations as low as 1 copy number/50 mu 1 reaction volume, and the duration between sample preparation and detection being 11 min. This detection platform may have the potential for use in point-of-care diagnostics.
Rapid and highly sensitive detection of Enterovirus 71 by using nanogold-enhanced electrochemical impedance spectroscopy (vol 24, 285102, 2013)
(2013-10-04)
Li, Hsing-Yuan
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Tseng, Shing-Hua
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Cheng, Tsai-Mu
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Chu, Hsueh-Liang
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Lu, Yu-Ning
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
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Murad, Yanal M.
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Chang, Chia-Ching
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Yang, Ming-Chi
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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.
Single molecular observation of the apolipoprotein B and its folding intermediates in reassembled low density lipoprotein
(2010-04-01)
Chang, Chia-Ching
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Chu, Hsueh-Liang
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Cheng, Tsai-Mu
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交大名義發表
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National Chiao Tung University
Synthesis of Apolipoprotein B Lipoparticles to Deliver Hydrophobic/Amphiphilic Materials
(2013-08-14)
Chu, Hsueh-Liang
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Cheng, Tsai-Mu
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Chen, Hung-Wei
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Chou, Fu-Hsuan
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Chang, Yu-Chuan
To develop a drug delivery system (DDS), it is critical to address challenging tasks such as the delivery of hydrophobic and amphiphilic compounds, cell uptake, and the metabolic fate of the drug delivery carrier. Low-density lipoprotein (LDL) has been acknowledged as the human serum transporter of natively abundant lipoparticles such as cholesterol, triacylglycerides, and lipids. Apolipoprotein B (apo B) is the only protein contained in LDL, and possesses a binding moiety for the LDL receptor that can be internalized and degraded naturally by the cell. Therefore, synthetic/reconstituting apoB lipoparticle (rABL) could be an excellent delivery carrier for hydrophobic or amphiphilic materials. Here, we synthesized rABL in vitro, using full-length apoB through a five-step solvent exchange method, and addressed its potential as a DDS. Our rABL exhibited good biocompatibility when evaluated with cytotoxicity and cell metabolic response assays, and was stable during storage in phosphate-buffered saline at 4 degrees C for several months. Furthermore, hydrophobic superparamagnetic iron oxide nanoparticles (SPIONPs) and the anticancer drug M4N (tetra-O-methyl nordihydroguaiaretic acid), used as an imaging enhancer and lipophilic drug model, respectively, were incorporated into the rABL, leading to the formation of SPIONPs- and M4N- containing rABL (SPIO@rABL and M4N@rABL, respectively). Fourier transform infrared spectroscopy suggested that rABL has a similar composition to that of LDL, and successfully incorporated SPIONPs or M4N. SPIO@rABL presented significant hepatic contrast enhancement in T-2-weighted magnetic resonance imaging in BALB/c mice, suggesting its potential application as a medical imaging contrast agent. M4N@rABL could reduce the viability of the cancer cell line A549. Interestingly, we developed solution-phase high-resolution transmission electron microscopy to observe both LDL and SPIO@rABL in the liquid state. In summary, our LDL-based DDS, rABL, has significant potential as a novel DDS for hydrophobic and amphiphilic materials, with good cell internalization properties and metabolicity.
Thermal stability and folding kinetics analysis of disordered protein, securin
(2014-03-01)
Chu, Hsueh-Liang
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Chen, Tzu-Hsuan
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Wu, Chang-You
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Yang, Yao-Chen
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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.
Two new, near-infrared, fluorescent probes as potential tools for imaging bone repair
(2020-02-13)
Lin, Chien-Chou
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Chang, Walter Hong-Shong
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Cheng, Tsai-Mu
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Chiu, Li-Hsuan
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Wang, Yen-Hsun
A precise imaging technique to evaluate osteogenesis, osteodifferentiation, and osseointegration following peri-implant surgery is in high clinical demand. Herein, we report the generation of two new, near-infrared (NIR) fluorescent probes for use in the molecular imaging of bone repair. The first probe aims to monitor the in vitro differentiation of human mesenchymal stem cells (MSCs) into osteoblasts. A NIR fluorochrome was conjugated to a cyclic peptide that binds to integrin alpha 5 beta 1, a factor that promotes osteogenesis in MSCs and therefore functioned as an osteoblast-specific marker. The second probe aims to monitor osteogenesis, and was generated by conjugating the drug pamidronate to a NIR fluorescent gold nanocluster. Pamidronate specifically binds to hydroxyapatite (HA), a mineral present in bone that is produced by osteoblasts, and therefore provides a functional marker for new bone formation. Our results show that both probes bind to their specific targets in vitro-differentiated osteoblasts, and not to undifferentiated MSCs, and emit NIR fluorescence for functional detection. This in vitro work demonstrates the ability of these probes to bind to active osteoblasts and their mineral deposits and highlight their potential utility as clinical tools for the imaging of the osseointegration process at the molecular level.