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Lin GB, Chen WT, Kuo YY, Chen YM, Liu HH, Chao CY. Protection of high-frequency low-intensity pulsed electric fields and brain-derived neurotrophic factor for SH-SY5Y cells against hydrogen peroxide-induced cell damage. Medicine (Baltimore) 2023; 102:e34460. [PMID: 37543811 PMCID: PMC10403004 DOI: 10.1097/md.0000000000034460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/07/2023] Open
Abstract
Neurodegenerative diseases (NDDs) pose a significant global health threat. In particular, Alzheimer disease, the most common type causing dementia, remains an incurable disease. Alzheimer disease is thought to be associated with an imbalance of reactive oxygen species (ROS) in neurons, and scientists considered ROS modulation as a promising strategy for novel remedies. In the study, human neural cell line SH-SY5Y was used in probing the effect of combining noninvasive high-frequency low-intensity pulsed electric field (H-LIPEF) and brain-derived neurotrophic factor (BDNF) in protection against hydrogen peroxide (H2O2)-induced neuron damage. Our result finds that the combination approach has intensified the neuroprotective effect significantly, perhaps due to H-LIPEF and BDNF synergistically increasing the expression level of the phosphorylated epidermal growth factor receptor (p-EGFR), which induces the survival-related mitogen-activated protein kinases (MAPK) proteins. The study confirmed the activation of extracellular signal-regulated kinase (ERK) and the downstream pro-survival and antioxidant proteins as the mechanism underlying neuron protection. These findings highlighted the potential of H-LIPEF combined with BDNF in the treatment of NDDs. Furthermore, BDNF-mimetic drugs combining with noninvasive H-LIPEF to patients is a promising approach worthy of further research. This points to strategies for selecting drugs to cooperate with electric fields in treating neurodegenerative disorders.
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Affiliation(s)
- Guan-Bo Lin
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
| | - Wei-Ting Chen
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
| | - Yu-Yi Kuo
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
| | - You-Ming Chen
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei, Taiwan
| | - Hsu-Hsiang Liu
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei, Taiwan
| | - Chih-Yu Chao
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei, Taiwan
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Kuo YY, Chen WT, Lin GB, Lu CH, Chao CY. Study on the effect of a triple cancer treatment of propolis, thermal cycling-hyperthermia, and low-intensity ultrasound on PANC-1 cells. Aging (Albany NY) 2023; 15:7496-7512. [PMID: 37506229 PMCID: PMC10457055 DOI: 10.18632/aging.204916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 07/06/2023] [Indexed: 07/30/2023]
Abstract
To reduce side effects and enhance treatment efficacy, study on combination therapy for pancreatic cancer, a deadly cancer, has gained much attraction in recent years. In this study, we propose a novel triple treatment combining propolis and two physical stimuli-thermal cycling-hyperthermia (TC-HT) and low-intensity ultrasound (US). The study found that, after the triple treatment, the cell viability of a human cancer cell line PANC-1 decreased to a level 80% less than the control, without affecting the normal pancreatic cells. Another result was excessive accumulation of reactive oxygen species (ROS) after the triple treatment, leading to the amplification of apoptotic pathway through the MAPK family and mitochondrial dysfunction. This study, to the best of our knowledge, is the first attempt to combine TC-HT, US, and a natural compound in cancer treatment. The combination of TC-HT and US also promotes the anticancer effect of the heat-sensitive chemotherapy drug cisplatin on PANC-1 cells. It is expected that optimized parameters for different agents and different types of cancer will expand the methodology on oncological therapy in a safe manner.
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Affiliation(s)
- Yu-Yi Kuo
- Department of Physics, Lab for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Molecular Imaging Center, National Taiwan University, Taipei, Taiwan
| | - Wei-Ting Chen
- Department of Physics, Lab for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Molecular Imaging Center, National Taiwan University, Taipei, Taiwan
| | - Guan-Bo Lin
- Department of Physics, Lab for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Molecular Imaging Center, National Taiwan University, Taipei, Taiwan
| | - Chueh-Hsuan Lu
- Department of Physics, Lab for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Molecular Imaging Center, National Taiwan University, Taipei, Taiwan
| | - Chih-Yu Chao
- Department of Physics, Lab for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Molecular Imaging Center, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei, Taiwan
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3
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Kuo YY, Chen WT, Lin GB, Chen YM, Liu HH, Chao CY. Thermal cycling-hyperthermia ameliorates Aβ 25-35-induced cognitive impairment in C57BL/6 mice. Neurosci Lett 2023; 810:137337. [PMID: 37315732 DOI: 10.1016/j.neulet.2023.137337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 06/16/2023]
Abstract
Despite continuation of some controversies, Alzheimer's disease (AD), the most common cause of dementia nowadays, has been widely believed to derive mainly from excessive β-amyloid (Aβ) aggregation, that would increase reactive oxygen species (ROS) and induce neuroinflammation, leading to neuron loss and cognitive impairment. Existing drugs on Aβ have been ineffective or offer only temporary relief at best, due to blood-brain barrier or severe side effects. The study employed thermal cycling-hyperthermia (TC-HT) to ease the Aβ-induced cognitive impairments and compared its effect with continuous hyperthermia (HT) in vivo. It established an AD mice model via intracerebroventricular (i.c.v.) injection of Aβ25-35, proving that TC-HT is much more effective in alleviating its performance decline in Y-maze and novel object recognition (NOR) tests, in comparison with HT. In addition, TC-HT also exhibits a better performance in decreasing the hippocampal Aβ and β-secretase (BACE1) expressions as well as the neuroinflammation markers-ionized calcium-binding adapter molecule 1 (Iba-1) and glial fibrillary acidic protein (GFAP) levels. Furthermore, the study finds that TC-HT can elevate more protein expressions of insulin degrading enzyme (IDE) and antioxidative enzyme superoxide dismutase 2 (SOD2) than HT. In sum, the study proves the potential of TC-HT in AD treatment, which can be put into application with the use of focused ultrasound (FUS).
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Affiliation(s)
- Yu-Yi Kuo
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei 10617, Taiwan; Molecular Imaging Center, National Taiwan University College of Medicine, Taipei 10051, Taiwan
| | - Wei-Ting Chen
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei 10617, Taiwan; Molecular Imaging Center, National Taiwan University College of Medicine, Taipei 10051, Taiwan
| | - Guan-Bo Lin
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei 10617, Taiwan; Molecular Imaging Center, National Taiwan University College of Medicine, Taipei 10051, Taiwan
| | - You-Ming Chen
- Molecular Imaging Center, National Taiwan University College of Medicine, Taipei 10051, Taiwan; Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei 10617, Taiwan
| | - Hsu-Hsiang Liu
- Molecular Imaging Center, National Taiwan University College of Medicine, Taipei 10051, Taiwan; Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei 10617, Taiwan
| | - Chih-Yu Chao
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei 10617, Taiwan; Molecular Imaging Center, National Taiwan University College of Medicine, Taipei 10051, Taiwan; Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei 10617, Taiwan.
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4
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Huang HJ, Tang SL, Chang YC, Wang HC, Ng TH, Garmann RF, Chen YW, Huang JY, Kumar R, Chang SH, Wu SR, Chao CY, Matoba K, Kenji I, Gelbart WM, Ko TP, Wang HJA, Lo CF, Chen LL, Wang HC. Multiple Nucleocapsid Structural Forms of Shrimp White Spot Syndrome Virus Suggests a Novel Viral Morphogenetic Pathway. Int J Mol Sci 2023; 24:ijms24087525. [PMID: 37108688 PMCID: PMC10140842 DOI: 10.3390/ijms24087525] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/11/2023] [Accepted: 04/15/2023] [Indexed: 04/29/2023] Open
Abstract
White spot syndrome virus (WSSV) is a very large dsDNA virus. The accepted shape of the WSSV virion has been as ellipsoidal, with a tail-like extension. However, due to the scarcity of reliable references, the pathogenesis and morphogenesis of WSSV are not well understood. Here, we used transmission electron microscopy (TEM) and cryogenic electron microscopy (Cryo-EM) to address some knowledge gaps. We concluded that mature WSSV virions with a stout oval-like shape do not have tail-like extensions. Furthermore, there were two distinct ends in WSSV nucleocapsids: a portal cap and a closed base. A C14 symmetric structure of the WSSV nucleocapsid was also proposed, according to our Cryo-EM map. Immunoelectron microscopy (IEM) revealed that VP664 proteins, the main components of the 14 assembly units, form a ring-like architecture. Moreover, WSSV nucleocapsids were also observed to undergo unique helical dissociation. Based on these new results, we propose a novel morphogenetic pathway of WSSV.
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Affiliation(s)
- Hui-Ju Huang
- Institute of Marine Biology, National Taiwan Ocean University, Keelung 20224, Taiwan
- Institute of Biological Chemistry, Academia Sinica, Nankang, Taipei 115, Taiwan
| | - Sen-Lin Tang
- Biodiversity Research Center, Academia Sinica, Taipei 11529, Taiwan
| | - Yuan-Chih Chang
- Institute of Biological Chemistry, Academia Sinica, Nankang, Taipei 115, Taiwan
| | - Hao-Ching Wang
- International Center for the Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan 701, Taiwan
- The Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei 110, Taiwan
- Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan
| | - Tze Hann Ng
- International Center for the Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan 701, Taiwan
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan 701, Taiwan
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117604, Singapore
| | - Rees F Garmann
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA 92182-1030, USA
| | - Yu-Wen Chen
- Biodiversity Research Center, Academia Sinica, Taipei 11529, Taiwan
| | - Jiun-Yan Huang
- International Center for the Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan 701, Taiwan
| | - Ramya Kumar
- International Center for the Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan 701, Taiwan
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan 701, Taiwan
| | - Sheng-Hsiung Chang
- International Center for the Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan 701, Taiwan
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan 701, Taiwan
| | - Shang-Rung Wu
- Institute of Oral Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Chih-Yu Chao
- Department of Physics and Graduate Institute of Applied Physics, National Taiwan University, Taipei 10617, Taiwan
- Molecular Imaging Center, National Taiwan University, Taipei 10617, Taiwan
| | - Kyoko Matoba
- Protein Synthesis and Expression, Institute for Protein Research, Osaka University, Osaka 565-0871, Japan
| | - Iwasaki Kenji
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba 305-8577, Japan
| | - William M Gelbart
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569, USA
| | - Tzu-Ping Ko
- Institute of Biological Chemistry, Academia Sinica, Nankang, Taipei 115, Taiwan
| | - Hwei-Jiung Andrew Wang
- Institute of Biological Chemistry, Academia Sinica, Nankang, Taipei 115, Taiwan
- The Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei 110, Taiwan
| | - Chu-Fang Lo
- International Center for the Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan 701, Taiwan
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan 701, Taiwan
| | - Li-Li Chen
- Institute of Marine Biology, National Taiwan Ocean University, Keelung 20224, Taiwan
- Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung 20224, Taiwan
| | - Han-Ching Wang
- International Center for the Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan 701, Taiwan
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan 701, Taiwan
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Chang CC, Algaissi A, Lai CC, Chang CK, Lin JS, Wang YS, Chang BH, Chang YC, Chen WT, Fan YQ, Peng BH, Chao CY, Tzeng SR, Liang PH, Sung WC, Hu AYC, Chang SC, Chang MF. Subunit vaccines with a saponin-based adjuvant boost humoral and cellular immunity to MERS coronavirus. Vaccine 2023; 41:3337-3346. [PMID: 37085450 PMCID: PMC10083212 DOI: 10.1016/j.vaccine.2023.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 02/15/2023] [Accepted: 04/03/2023] [Indexed: 04/23/2023]
Abstract
Middle East respiratory syndrome coronavirus (MERS-CoV) outbreaks have constituted a public health issue with drastic mortality higher than 34%, necessitating the development of an effective vaccine. During MERS-CoV infection, the trimeric spike protein on the viral envelope is primarily responsible for attachment to host cellular receptor, dipeptidyl peptidase 4 (DPP4). With the goal of generating a protein-based prophylactic, we designed a subunit vaccine comprising the recombinant S1 protein with a trimerization motif (S1-Fd) and examined its immunogenicity and protective immune responses in combination with various adjuvants. We found that sera from immunized wild-type and human DPP4 transgenic mice contained S1-specific antibodies that can neutralize MERS-CoV infection in susceptible cells. Vaccination with S1-Fd protein in combination with a saponin-based QS-21 adjuvant provided long-term humoral as well as cellular immunity in mice. Our findings highlight the significance of the trimeric S1 protein in the development of MERS-CoV vaccines and offer a suitable adjuvant, QS-21, to induce robust and prolonged memory T cell response.
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Affiliation(s)
- Chi-Chieh Chang
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Abdullah Algaissi
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, TX 77555, USA; Center for Biodefense and Emerging Disease, The University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Chia-Chun Lai
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli County 35053, Taiwan; College of Life Science, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Chun-Kai Chang
- School of Pharmacy, College of Medicine, National Taiwan University, Taipei 100025, Taiwan
| | - Jr-Shiuan Lin
- Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Yi-Shiang Wang
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Bo-Hau Chang
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Yu-Chiuan Chang
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Wei-Ting Chen
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Yong-Qing Fan
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Bi-Hung Peng
- Department of Neurosciences, The University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Chih-Yu Chao
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Shiou-Ru Tzeng
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Pi-Hui Liang
- School of Pharmacy, College of Medicine, National Taiwan University, Taipei 100025, Taiwan
| | - Wang-Chou Sung
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli County 35053, Taiwan
| | - Alan Yung-Chih Hu
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli County 35053, Taiwan
| | - Shin C Chang
- Institute of Microbiology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Ming-Fu Chang
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan.
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Chen WT, Lin GB, Kuo YY, Hsieh CH, Lu CH, Sun YK, Chao CY. Effect of high-frequency low-intensity pulsed electric field on protecting SH-SY5Y cells against hydrogen peroxide and β-amyloid-induced cell injury via ERK pathway. PLoS One 2021; 16:e0250491. [PMID: 33901243 PMCID: PMC8075192 DOI: 10.1371/journal.pone.0250491] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 04/08/2021] [Indexed: 11/21/2022] Open
Abstract
As the most common type of neurodegenerative diseases (NDDs), Alzheimer's disease (AD) is thought to be caused mainly by the excessive aggregation of β-amyloid protein (Aβ). However, a growing number of studies have found that reactive oxygen species (ROS) play a key role in the onset and progression of AD. The present study aimed to probe the neuroprotective effect of high-frequency low-intensity pulsed electric field (H-LIPEF) for SH-SY5Y cells against hydrogen peroxide (H2O2) and Aβ-induced cytotoxicity. By looking in a systematic way into the frequency- and amplitude-dependent neuroprotective effect of pulsed electric field (PEF), the study finds that H-LIPEF at 200 Hz produces the optimal protective effect for SH-SY5Y cells. The underlying mechanisms were confirmed to be due to the activation of extracellular signal-regulated kinase (ERK) pathway and the downstream prosurvival and antioxidant proteins. Because the electric field can be modified to focus on specific area in a non-contact manner, the study suggests that H-LIPEF holds great potential for treating NDDs, whose effect can be further augmented with the administering of drugs or natural compounds at the same time.
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Affiliation(s)
- Wei-Ting Chen
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Guan-Bo Lin
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yu-Yi Kuo
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chih-Hsiung Hsieh
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chueh-Hsuan Lu
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yi-Kun Sun
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chih-Yu Chao
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei, Taiwan
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Chen WT, Kuo YY, Lin GB, Lu CH, Hsu HP, Sun YK, Chao CY. Thermal cycling protects SH-SY5Y cells against hydrogen peroxide and β-amyloid-induced cell injury through stress response mechanisms involving Akt pathway. PLoS One 2020; 15:e0240022. [PMID: 33002038 PMCID: PMC7529293 DOI: 10.1371/journal.pone.0240022] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 09/17/2020] [Indexed: 12/24/2022] Open
Abstract
Neurodegenerative diseases (NDDs) are becoming a major threat to public health, according to the World Health Organization (WHO). The most common form of NDDs is Alzheimer’s disease (AD), boasting 60–70% share. Although some debates still exist, excessive aggregation of β-amyloid protein (Aβ) and neurofibrillary tangles has been deemed one of the major causes for the pathogenesis of AD. A growing number of evidences from studies, however, have suggested that reactive oxygen species (ROS) also play a key role in the onset and progression of AD. Although scientists have had some understanding of the pathogenesis of AD, the disease still cannot be cured, with existing treatment only capable of providing a temporary relief at best, partly due to the obstacle of blood-brain barrier (BBB). The study was aimed to ascertain the neuroprotective effect of thermal cycle hyperthermia (TC-HT) against hydrogen peroxide (H2O2) and Aβ-induced cytotoxicity in SH-SY5Y cells. Treating cells with this physical stimulation beforehand significantly improved the cell viability and decreased the ROS content. The underlying mechanisms may be due to the activation of Akt pathway and the downstream antioxidant and prosurvival proteins. The findings manifest significant potential of TC-HT in neuroprotection, via inhibition of oxidative stress and cell apoptosis. It is believed that coupled with the use of drugs or natural compounds, this methodology can be even more effective in treating NDDs.
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Affiliation(s)
- Wei-Ting Chen
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yu-Yi Kuo
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Guan-Bo Lin
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chueh-Hsuan Lu
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Hao-Ping Hsu
- Department of Medicine, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yi-Kun Sun
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chih-Yu Chao
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei, Taiwan
- * E-mail:
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Lu CH, Kuo YY, Lin GB, Chen WT, Chao CY. Application of non-invasive low-intensity pulsed electric field with thermal cycling-hyperthermia for synergistically enhanced anticancer effect of chlorogenic acid on PANC-1 cells. PLoS One 2020; 15:e0222126. [PMID: 31995555 PMCID: PMC6988950 DOI: 10.1371/journal.pone.0222126] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 01/09/2020] [Indexed: 12/21/2022] Open
Abstract
Most existing cancer treatments involve high-cost chemotherapy and radiotherapy, with major side effects, prompting effort to develop alternative treatment modalities. It was reported that the combination of thermal-cycling hyperthermia (TC-HT) and phenolic compound exhibited a moderate cytotoxic effect against human pancreatic cancer PANC-1 cells. In this study, we investigate the efficacy of triple combination in PANC-1 cancer cells by adopting low-intensity pulsed electric field (LIPEF) to couple with TC-HT and CGA (chlorogenic acid). The study finds that this triple combination can significantly impede the proliferation of PANC-1 cells, with only about 20% viable cells left after 24h, whereas being non-toxic to normal cells. The synergistic activity against the PANC-1 cells was achieved by inducing G2/M phase arrest and apoptosis, which were associated with up-regulation of p53 and coupled with increased expression of downstream proteins p21 and Bax. Further mechanism investigations revealed that the cytotoxic activity could be related to mitochondrial apoptosis, characterized by the reduced level of Bcl-2, mitochondrial dysfunction, and sequential activation of caspase-9 and PARP. Also, we found that the triple treatment led to the increase of intracellular reactive oxygen species (ROS) production. Notably, the triple treatment-induced cytotoxic effects and the elevated expression of p53 and p21 proteins as well as the increased Bax/Bcl-2 ratio, all could be alleviated by the ROS scavenger, N-acetyl-cysteine (NAC). These findings indicate that the combination of CGA, TC-HT, and LIPEF may be a promising modality for cancer treatment, as it can induce p53-dependent cell cycle arrest and apoptosis through accumulation of ROS in PANC-1 cells.
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Affiliation(s)
- Chueh-Hsuan Lu
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yu-Yi Kuo
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Guan-Bo Lin
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Wei-Ting Chen
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chih-Yu Chao
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Institute of Applied Physics, National Taiwan University, Taipei, Taiwan
- * E-mail:
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Chen WT, Sun YK, Lu CH, Chao CY. Thermal cycling as a novel thermal therapy to synergistically enhance the anticancer effect of propolis on PANC‑1 cells. Int J Oncol 2019; 55:617-628. [PMID: 31322205 PMCID: PMC6685589 DOI: 10.3892/ijo.2019.4844] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 07/01/2019] [Indexed: 01/14/2023] Open
Abstract
Hyperthermia (HT) has shown potential in cancer therapy. In particular, it appears to sensitize cancer cells to chemotherapy. However, a major concern associated with HT is that the thermal dosage applied to the tumor cells may also harm the normal tissue cells. Besides, the drugs used in HT are conventional chemotherapy drugs, which may cause serious side effects. The present study demonstrated a novel methodology in HT therapy called thermal cycle (TC)‑HT. With this strategy, a therapeutic window with a maximum synergistic effect was created by combining TC‑HT with natural compounds, with minimal unwanted cell damage. The natural compound propolis was selected, and the synergistic anticancer effect of TC‑HT and propolis was investigated in pancreatic cancer cells. The present results demonstrated for the first time that TC‑HT could enhance the anticancer effect of propolis on PANC‑1 cancer cells through the mitochondria‑dependent apoptosis pathway and cell cycle arrest. Combined treatment greatly suppressed mitochondrial membrane potential, which is an important indicator of damaged and dysfunctional mitochondria. Furthermore, the cell cycle‑regulating protein cell division cycle protein 2 was downregulated upon combined treatment, which prevented cellular progression into mitosis. The present study offers the first report, to the best of our knowledge, on the combination of TC‑HT with a natural compound for pancreatic cancer treatment. It is anticipated that this methodology may be a starting point for more sophisticated cancer treatments and may thereby improve the quality of life of many patients with cancer.
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Affiliation(s)
- Wei-Ting Chen
- Department of Physics, Laboratory for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei 10617
- Biomedical and Molecular Imaging Center, National Taiwan University College of Medicine, Taipei 10051
| | - Yi-Kun Sun
- Biomedical and Molecular Imaging Center, National Taiwan University College of Medicine, Taipei 10051
| | - Chueh-Hsuan Lu
- Department of Physics, Laboratory for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei 10617
- Biomedical and Molecular Imaging Center, National Taiwan University College of Medicine, Taipei 10051
| | - Chih-Yu Chao
- Department of Physics, Laboratory for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei 10617
- Biomedical and Molecular Imaging Center, National Taiwan University College of Medicine, Taipei 10051
- Institute of Applied Physics, National Taiwan University, Taipei 10617, Taiwan, R.O.C
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Lu CH, Chen WT, Hsieh CH, Kuo YY, Chao CY. Thermal cycling-hyperthermia in combination with polyphenols, epigallocatechin gallate and chlorogenic acid, exerts synergistic anticancer effect against human pancreatic cancer PANC-1 cells. PLoS One 2019; 14:e0217676. [PMID: 31150487 PMCID: PMC6544372 DOI: 10.1371/journal.pone.0217676] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 05/16/2019] [Indexed: 02/06/2023] Open
Abstract
Hyperthermia (HT) has shown feasibility and potency as an anticancer therapy. Administration of HT in the chemotherapy has previously enhanced the cytotoxicity of drugs against pancreatic cancer. However, the drugs used when conducting these studies are substantially conventional chemotherapeutic agents that may cause unwanted side effects. Additionally, the thermal dosage in the treatment of cancer cells could also probably harm the healthy cells. The purpose of this work was to investigate the potential of the two natural polyphenolic compounds, epigallocatechin gallate (EGCG) and chlorogenic acid (CGA), as heat synergizers in the thermal treatment of the PANC-1 cells. Furthermore, we have introduced a unique strategy entitled the thermal cycling-hyperthermia (TC-HT) that is capable of providing a maximum synergy and minimal side effect with the anticancer compounds. Our results demonstrate that the combination of the TC-HT and the CGA or EGCG markedly exerts the anticancer effect against the PANC-1 cells, while none of the single treatment induced such changes. The synergistic activity was attributed to the cell cycle arrest at the G2/M phase and the induction of the ROS-dependent mitochondria-mediated apoptosis. These findings not only represent the first in vitro thermal synergistic study of natural compounds in the treatment of pancreatic cancer, but also highlight the potential of the TC-HT as an alternative strategy in thermal treatment.
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Affiliation(s)
- Chueh-Hsuan Lu
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Wei-Ting Chen
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chih-Hsiung Hsieh
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yu-Yi Kuo
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chih-Yu Chao
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Institute of Applied Physics, National Taiwan University, Taipei, Taiwan
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Lu CH, Lin SH, Hsieh CH, Chen WT, Chao CY. Enhanced anticancer effects of low-dose curcumin with non-invasive pulsed electric field on PANC-1 cells. Onco Targets Ther 2018; 11:4723-4732. [PMID: 30127620 PMCID: PMC6091485 DOI: 10.2147/ott.s166264] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Background Pulsed electric field (PEF) has been considered as a cell permeability enhancing agent for cancer treatment. Nevertheless, application of PEF for conventional electrochemo-therapy is usually at high intensity, and contact or even invasive electrodes are typically used, which may cause unwanted side effects. In this study, a non-invasive way of applying low intensity, non-contact PEF was adopted to study its combination effect with herb, curcumin, against pancreatic cancer cells and the mechanism involved. Methods The pancreatic cancer PANC-1 cells were treated with curcumin and PEF alone or in combination, and MTT assay was used to determine the viability of PANC-1 cells. Apoptosis and uptake of curcumin were analyzed by microscopy and flow cytometry. Western blot was further performed to evaluate the expression of apoptotic proteins. Results Our results demonstrated that PEF synergized with curcumin to inhibit the proliferation of PANC-1 cells in a field strength- and dose-dependent manner and caused apoptotic death of PANC-1 cells. The apoptotic induction of combination treatment was characterized by an increase in Bax/Bcl-2 ratio, and cleavage of caspase-8, -9, and -3. Moreover, the increase of curcumin uptake via electro-endocytosis was clearly observed in the cells following the exposure of PEF. Conclusion We show for the first time that a non-contact approach using low intensity electric field in a pulsed waveform could enhance the anticancer effect of low-dose curcumin on PANC-1 cells through triggering both extrinsic and intrinsic pathways. The findings highlight the potential of this alternative treatment, non-invasive electric field and curcumin, to increase therapeutic efficacy with minimum cytotoxicity and side effects, which may provide a new aspect of cancer treatment in combination of PEF and other anticancer agents.
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Affiliation(s)
- Chueh-Hsuan Lu
- Department of Physics, Lab for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei, Taiwan, Republic of China, .,Biomedical and Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan, Republic of China,
| | - Shu-Hui Lin
- Biomedical and Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan, Republic of China,
| | - Chih-Hsiung Hsieh
- Department of Physics, Lab for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei, Taiwan, Republic of China, .,Biomedical and Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan, Republic of China,
| | - Wei-Ting Chen
- Department of Physics, Lab for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei, Taiwan, Republic of China, .,Biomedical and Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan, Republic of China,
| | - Chih-Yu Chao
- Department of Physics, Lab for Medical Physics and Biomedical Engineering, National Taiwan University, Taipei, Taiwan, Republic of China, .,Biomedical and Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan, Republic of China, .,Institute of Applied Physics, National Taiwan University, Taipei, Taiwan, Republic of China,
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Hsieh CH, Lu CH, Kuo YY, Chen WT, Chao CY. Studies on the non-invasive anticancer remedy of the triple combination of epigallocatechin gallate, pulsed electric field, and ultrasound. PLoS One 2018; 13:e0201920. [PMID: 30080905 PMCID: PMC6078317 DOI: 10.1371/journal.pone.0201920] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 07/24/2018] [Indexed: 12/17/2022] Open
Abstract
Cancer is one of the most troublesome diseases and a leading cause of death worldwide. Recently, novel treatments have been continuously developed to improve the disadvantages of conventional therapies, such as prodigious expenses, unwanted side effects, and tumor recurrence. Here, we provide the first non-invasive treatment that has combined epigallocatechin gallate (EGCG), the most abundant catechin in green tea, with a low strength pulsed electric field (PEF) and a low energy ultrasound (US). It has been observed that the cell viability of human pancreatic cancer PANC-1 was decreased approximately to 20% of the control after this combination treatment for 72 h. Besides, the combined triple treatment significantly reduced the high tolerance of HepG2 cells to the EGCG-induced cytotoxicity and similarly exhibited compelling proliferation-inhibitory effects. We also found the combined triple treatment increased the intracellular reactive oxygen species (ROS) and acidic vesicles, and the EGCG-induced inhibition of Akt phosphorylation was dramatically intensified. In this study, the apoptosis inhibitor Z-VAD-FMK and the autophagy inhibitor 3-MA were, respectively, shown to attenuate the anticancer effects of the triple treatment. This indicates that the triple treatment-induced autophagy was switched from cytoprotective to cytotoxic, and hence, cooperatively caused cell death with the apoptosis. Since the EGCG is easily accessible from the green tea and mild for a long-term treatment, and the non-invasive physical stimulations could be modified to focus on a specific location, this combined triple treatment may serve as a promising strategy for anticancer therapy.
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Affiliation(s)
- Chih-Hsiung Hsieh
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chueh-Hsuan Lu
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yu-Yi Kuo
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Wei-Ting Chen
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chih-Yu Chao
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Institute of Applied Physics, National Taiwan University, Taipei, Taiwan
- * E-mail:
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Chao CY, Wang CH, Che YJ, Kao CY, Wu JJ, Lee GB. An integrated microfluidic system for diagnosis of the resistance of Helicobacter pylori to quinolone-based antibiotics. Biosens Bioelectron 2016; 78:281-289. [DOI: 10.1016/j.bios.2015.11.046] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 11/13/2015] [Accepted: 11/14/2015] [Indexed: 01/02/2023]
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Huang CC, Kuo YY, Chen SH, Chen WT, Chao CY. Liquid-crystal-modulated correlated color temperature tunable light-emitting diode with highly accurate regulation. Opt Express 2015; 23:A149-A156. [PMID: 25836243 DOI: 10.1364/oe.23.00a149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A precise correlated color temperature (CCT) tuning method for light-emitting diodes (LEDs) has been developed and is demonstrated in this article. By combining LEDs and a liquid crystal (LC) cell, a light source with continuous CCT variation along a straight track on the chromaticity diagram is achieved. Moreover, the manner of CCT variation can be modulated by choosing appropriate LEDs and phosphors to yield a variation going from 3800 K to 6100 K with the track near the black-body locus. By adapting various developed LC technologies for diverse demands, the performance and applications of LEDs can be greatly improved.
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Chiang YT, Chou TR, Chao CY. Enhancement of electro-optical properties of twisted nematic liquid crystals by doping aromatic hydrocarbon liquids. Opt Express 2014; 22:30882-30888. [PMID: 25607037 DOI: 10.1364/oe.22.030882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this paper, doping liquid materials to enhance the electro-optical (EO) properties of twisted nematic liquid crystals (NLCs) was presented. Two aromatic hydrocarbon (AH) liquids, toluene and 1-methylnaphthalene, were chosen as dopants in order to lower the driving voltage and response time of the NLCs. A 18% decrease in driving voltage and response time was achieved by doping 10 wt% toluene into NLCs. The main reason of this phenomenon is due to a large amount of reduction in the rotational viscosity of AH liquids doped NLCs. This method provides an easy and potential choice for applications in various LC display systems.
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Chen JW, Huang CC, Chao CY. Supramolecular liquid-crystal gels formed by polyfluorene-based π-conjugated polymer for switchable anisotropic scattering device. ACS Appl Mater Interfaces 2014; 6:6757-64. [PMID: 24724859 DOI: 10.1021/am500518c] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
To overcome the problem of high driving voltage and low contrast ratio in the switchable scattering device of conventional liquid-crystal (LC) physical gel, a new type of supramolecular LC physical gel has been developed and fabricated through the fibrous self-assembly of the polyfluorene-based π-conjugated polymer, poly(9,9-dioctylfluorene-alt-benzothiadiazole) (F8BT), in nematic LC mixture E7. It was found that the rubbed interface between the LC molecules and polyimide layer can induce the LC physical gels to demonstrate fantastic light scattering characteristic. The gels with oriented self-assembled supramolecular structures exhibiting significant anisotropic light scattering in the main-chain direction of the F8BT molecules under an extremely low driving voltage (ca. 2.7 V) are reported for the first time. In addition, the contrast ratio can be reached exceeding 1000. In contrast to conventional LC physical gels, the large reduction of driving voltages of the supramolecular gel provides great possibility for application in various electro-optical devices such as tunable polarizers, transflective displays, and polarized light modulators.
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Affiliation(s)
- Jun-Wei Chen
- Department of Physics, National Taiwan University , Taipei 10617, Taiwan, R.O.C
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Wu TC, Chao CY, Lin SJ, Chen JW. Low-dose dextromethorphan, a NADPH oxidase inhibitor, reduces blood pressure and enhances vascular protection in experimental hypertension. PLoS One 2012; 7:e46067. [PMID: 23049937 PMCID: PMC3457948 DOI: 10.1371/journal.pone.0046067] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 08/28/2012] [Indexed: 01/10/2023] Open
Abstract
Background Vascular oxidative stress may be increased with age and aggravate endothelial dysfunction and vascular injury in hypertension. This study aimed to investigate the effects of dextromethorphan (DM), a NADPH oxidase inhibitor, either alone or in combination treatment, on blood pressure (BP) and vascular protection in aged spontaneous hypertensive rats (SHRs). Methodology/Principal Findings Eighteen-week-old WKY rats and SHRs were housed for 2 weeks. SHRs were randomly assigned to one of the 12 groups: untreated; DM monotherapy with 1, 5 or 25 mg/kg/day; amlodipine (AM, a calcium channel blocker) monotherapy with 1 or 5 mg/kg/day; and combination therapy of DM 1, 5 or 25 mg/kg/day with AM 1 or 5 mg/kg/day individually for 4 weeks. The in vitro effects of DM were also examined. In SHRs, AM monotherapy dose-dependently reduced arterial systolic BP. DM in various doses significantly and similarly reduced arterial systolic BP. Combination of DM with AM gave additive effects on BP reduction. DM, either alone or in combination with AM, improved aortic endothelial function indicated by ex vivo acetylcholine-induced relaxation. The combination of low-dose DM with AM gave most significant inhibition on aortic wall thickness in SHRs. Plasma total antioxidant status was significantly increased by all the therapies except for the combination of high-dose DM with high-dose AM. Serum nitrite and nitrate level was significantly reduced by AM but not by DM or the combination of DM with AM. Furthermore, in vitro treatment with DM reduced angiotensin II-induced reactive oxygen species and NADPH oxidase activation in human aortic endothelial cells. Conclusions/Significance Treatment of DM reduced BP and enhanced vascular protection probably by inhibiting vascular NADPH oxidase in aged hypertensive animals with or without AM treatment. It provides the potential rationale to a novel combination treatment with low-dose DM and AM in clinical hypertension.
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Affiliation(s)
- Tao-Cheng Wu
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
- Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Chih-Yu Chao
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Shing-Jong Lin
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
- Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan, ROC
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan, ROC
- Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Jaw-Wen Chen
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
- Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan, ROC
- Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
- Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan, ROC
- * E-mail:
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Abstract
To study lead (Pb) distribution in organs and blood in the case of Pb poisoning, mice were firstly exposed to Pb as 0.1 mL or 0.2 mL of lead nitrate solution (0.1 mg/mL) by vein injection every other day. Then, after metabolic absorption, the Pb level in the blood and organs of the mice was measured using flame atomic absorption spectrometry. The resulting data showed that 93% of Pb in blood was accumulated in red cells, but this percentage slightly decreased with increasing exposure time and injection volume. For other target organs, the highest Pb level was in the kidney, followed by the liver, spleen, heart and lung, and was lowest in the brain. Moreover, the Pb level in the heart and brain is in a growth trend at all times for 0.1 mL and 0.2 mL of Pb injection exposure in 15 days, while the growth trend of Pb in other target organs become slow for 0.2 mL of injection after exposure Pb 11 days.
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Affiliation(s)
- H W Sun
- College of Chemistry and Environment, Hebei University, Baoding, 071002, China
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Affiliation(s)
- C Y Chao
- Norman Bridge Laboratory of Physics, California Institute of Technology
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Wan MP, Chao CY. Numerical and experimental study of velocity and temperature characteristics in a ventilated enclosure with underfloor ventilation systems. Indoor Air 2005; 15:342-55. [PMID: 16108907 DOI: 10.1111/j.1600-0668.2005.00378.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
UNLABELLED Airflow and temperature distributions in an enclosure with heat sources ventilated by floor supply jets with floor or ceiling air exit vents were investigated using experimental and numerical approaches. These ventilation configurations represent the floor return or the top return underfloor ventilation systems found in real applications. Experiments and numerical simulations were performed on a full-sized environmental chamber. The results reveal that the temperature stratification in the enclosure highly depended on the thermal length scale of the floor supply jets. When the thermal length scale of the supply jet was >>1, temperature stratification was minor for all tested heat densities and air distribution methods. Significant vertical temperature gradients occurred when the jet thermal length scale was <<1. Changes in air distribution methods also became significant for temperature stratification at small supply jet thermal length scales. Temperature stratification also affected the terminal height of the momentum-dominant region of the vertical buoyant supply jets. The applicability of these results to underfloor ventilation design was also discussed. PRACTICAL IMPLICATIONS In designing underfloor ventilation systems, supply jet conditions and heat load density have to be considered to avoid thermal discomfort because of excessive temperature stratifications. This study demonstrated, by both numerical simulations and experiments, that thermal length scale can be used as a design indicator to predict thermal stratifications under a floor return and a top return underfloor ventilation setting.
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Affiliation(s)
- M P Wan
- Department of Mechanical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong
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Abstract
An intermediate surface hexatic phase between the liquid and the crystalline phases has been found for the first time in a lyotropic lamellar liquid-crystal system. This phase is highly unusual in that it has long-range sixfold bond-orientational order but liquidlike nearest-neighbor positional correlations, and could represent a significant departure from our current understanding of defect-mediated melting in two dimensions.
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Affiliation(s)
- Chih-Yu Chao
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan, Republic of China.
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Chao CY, Wan MP. Experimental study of ventilation performance and contaminant distribution of underfloor ventilation systems vs. traditional ceiling-based ventilation system. Indoor Air 2004; 14:306-316. [PMID: 15330790 DOI: 10.1111/j.1600-0668.2004.00248.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
UNLABELLED Ventilation performance and pollutant distribution in a traditional ceiling-type ventilation system, a top-return (TR)-type and a floor-return (FR)-type underfloor ventilation systems were performed in a controlled experimental room. Tracer gas method was utilized to determine the age of air and the contaminant removal effectiveness. Tobacco smoke was also introduced to study the particle-phase pollutant distribution. The TR system delivered conditioned air more efficiently in the occupied zone and exhibited higher gaseous contaminant removal effectiveness. It also showed the lowest smoke particle concentration compared with the other two systems. The FR system showed better ventilation performance over the mixing system at the space that was close to the floor supply outlet and at the lower height level. The FR system was less effective than the TR system in removing buoyant tobacco smoke particles at the upper part of the room indicating its highly localized characteristics. Differences in experimental conditions between the present and the previous studies and their effects on the experimental results are discussed. In general, the experimental data suggested that both types of the underfloor ventilation systems have the potential of improving air quality at the breathing zone over the ceiling-based mixing system with suitable designs. PRACTICAL IMPLICATIONS This study shows the possibility of improving indoor air quality using underfloor ventilation systems compared with the traditional ceiling-based ventilation system. However, different configurations of the underfloor ventilation system show various ventilation characteristics. The engineers should consider these features when implementing an underfloor ventilation design. The top-return (TR) configuration improves indoor air quality by creating a displacement-like flow pattern while the floor-return (FR) configuration shows highly localized ventilation characteristics. The FR configuration improved the indoor air quality at spaces near the floor diffusers and up to certain heights.
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Affiliation(s)
- C Y Chao
- Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
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Pan TC, Hsieh WJ, Chao CY. Thickness-dependent smectic- A–smectic- C*transition in chiral smectic free-standing liquid-crystal films. Phys Rev E 2004; 70:011706. [PMID: 15324071 DOI: 10.1103/physreve.70.011706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2003] [Indexed: 11/07/2022]
Abstract
We have conducted heat-capacity measurements near the smectic-A -smectic-C* phase transition in free-standing films of a chiral liquid-crystal compound. The heat-capacity behavior confirms the evolution of the transition in the interior layers from first to second order as a function of film thickness suggested earlier in tilt angle measurements. The asymmetry in the heat-capacity anomaly exhibits an interesting crossover in thinner films. We also observed the phase transitions leading to the crystallization to the tilted crystal-G phase in these films at lower temperatures. The surface ordering strength in these films is found to be much larger than that in other orthogonal-smectic films, which we speculate is due to the molecular tilt.
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Affiliation(s)
- Tung-Cheng Pan
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan, Republic of China
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Chao CY, Pan TC, Chou CF, Ho JT. Multiple electron diffraction and two-dimensional crystalline order in liquid-crystal thin films. Phys Rev Lett 2003; 91:125504. [PMID: 14525373 DOI: 10.1103/physrevlett.91.125504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2003] [Indexed: 05/24/2023]
Abstract
Electron diffraction in freestanding thin films in the crystal-B phase reveals extensive multiple diffraction in films of 14S5 but not of 4O.8, suggesting an important difference in the structural order in these films despite the similarities in their positional correlations found in earlier experiments. The result in a two-layer 14S5 film indicates surprisingly that secondary diffraction can occur in a crystal with only pseudo-long-range positional order.
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Affiliation(s)
- Chih-Yu Chao
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan, Republic of China.
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Chao CY, Pan TC, Ho JT. Surface phase transitions in free-standing films of nonchiral tilted hexatic liquid crystals. Phys Rev E Stat Nonlin Soft Matter Phys 2003; 67:040702. [PMID: 12786339 DOI: 10.1103/physreve.67.040702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2003] [Indexed: 05/24/2023]
Abstract
Surface freezing transitions in free-standing films of achiral Schiff's-base liquid crystals 5O.6 and 7O.7 exhibiting tilted hexatic phases have been studied using optical textures. The evolution of textures with temperature in 5O.6 films is qualitatively similar to that reported earlier in the ferphenyl ester FTE1, suggesting the existence of the surface smectic-L phase, except that the stripe texture in 5O.6 consists of alternating light and dark stripes of unequal widths. No stripe texture is observed in 7O.7.
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Affiliation(s)
- Chih-Yu Chao
- Department of Physics, National Taiwan University, Taipei 10617, Republic of China.
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Chao CY, Lo CR, Wu PJ, Pan TC, Veum M, Huang CC, Surendranath V, Ho JT. Unusual thickness-dependent heat-capacity anomalies in free-standing hexatic liquid-crystal films. Phys Rev Lett 2002; 88:085507. [PMID: 11863962 DOI: 10.1103/physrevlett.88.085507] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2001] [Indexed: 05/23/2023]
Abstract
High-resolution heat-capacity and optical-reflectivity measurements have been conducted near the smectic-A to hexatic-B transition in thin free-standing films of the liquid-crystal compound 64COOBC. We find an unexpected dependence on film thickness of the integrated magnitude of the heat-capacity anomalies as the films undergo layer-by-layer transitions. We measure the penetration depths of the ordering from the surface and next-to-surface layers which are pertinent to the highly correlated thermal behavior.
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Affiliation(s)
- C Y Chao
- Department of Physics and Astronomy, National Central University, Chung-Li 32054, Taiwan, Republic of China.
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Chao PM, Chao CY, Lin FJ, Huang C. Oxidized frying oil up-regulates hepatic acyl-CoA oxidase and cytochrome P450 4 A1 genes in rats and activates PPARalpha. J Nutr 2001; 131:3166-74. [PMID: 11739861 DOI: 10.1093/jn/131.12.3166] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Oxidized LDL (oxLDL) and its component hydroxy fatty acids were shown to activate peroxisome proliferator-activating receptor alpha (PPARalpha) and gamma (PPARgamma). To test the hypothesis that lipid oxidation products in oxidized frying oil (OFO) can activate PPARalpha and up-regulate its target genes, a feeding experiment and a transactivation experiment were conducted. Based on a 2 x 2 factorial design, four groups of Sprague-Dawley male weanling rats were fed diets containing either high (20 g/100 g, HO and HF) or low (5 g/100 g, LO and LF) levels of oxidized frying soybean oil (HO and LO) or fresh soybean oil (HF and LF) for 6 wk. The OFO sample was prepared by frying wheat dough sheets in soybean oil at 205 +/- 5 degrees C for 24 h. OFO dose dependently and significantly increased (P < 0.05) mRNA of acyl-CoA oxidase (ACO) and cytochrome P(450) 4A1(CYP4A1) in liver of rats. Dietary OFO also dose dependently increased liver microsomal CYP4A protein (P < 0.05). The activity of hepatic ACO of the HO group was sixfold that of the HF group (P < 0.05). Plasma total lipids, liver triglycerides, cholesterol and total lipids were reduced in rats fed the LO and HO diets (P < 0.05). Through the ligand binding domain of PPARalpha, the hydrolyzed OFO enhanced the expression of alkaline phosphatase (ALP) reporter gene to a significantly greater extent (P < 0.05) than the hydrolyzed fresh soybean oil in a transactivation assay using a clone of CHO K1 cells stably expressing Gal4-PPARalpha chimeric receptor and UAS4-ALP reporter. The results support our hypothesis that dietary OFO, by activating PPARalpha, up-regulates the expression of PPARalpha downstream genes and alters lipid metabolism in rats.
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Affiliation(s)
- P M Chao
- Laboratory of Nutritional Biochemistry, Department of Agricultural Chemistry, National Taiwan University, Taipei 106, Taiwan
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Chao CY, Liu YH, Pan TC, Chang BN, Ho JT. Direct layer-by-layer freezing of a smectic liquid-crystal surface into the crystalline phase. Phys Rev E Stat Nonlin Soft Matter Phys 2001; 64:050703. [PMID: 11735887 DOI: 10.1103/physreve.64.050703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2001] [Indexed: 05/23/2023]
Abstract
Electron diffraction and optical reflectivity have provided the direct confirmation of the existence of layer-by-layer surface transitions from the smectic-A immediately to the crystal-B phase in a liquid-crystal material, without going through an intermediate hexatic phase. The molecular interactions are found to be through retarded van der Waals forces. Our results suggest that a smectic-A film can transform into a crystal-B through three possible scenarios.
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Affiliation(s)
- C Y Chao
- Department of Physics and Astronomy, National Central University, Chung-Li 32054, Taiwan, Republic of China.
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Chao CY, Lo CR, Wu PJ, Liu YH, Link DR, Maclennan JE, Clark NA, Veum M, Huang CC, Ho JT. Unusual thickness-dependent thermal behavior and anticlinic coupling in chiral smectic free-standing liquid-crystal films. Phys Rev Lett 2001; 86:4048-4051. [PMID: 11328092 DOI: 10.1103/physrevlett.86.4048] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2000] [Indexed: 05/23/2023]
Abstract
We observe, in free-standing films of a chiral smectic liquid crystal, a series of discrete transitions in the relative orientation of the tilt of the interior and surface layers. These transitions include a remarkable reentrant synclinic-anticlinic-synclinic ordering sequence of the film surfaces in the presence of an electric field upon cooling. The profiles of the associated heat-capacity anomalies are found to be strongly thickness dependent and exhibit a novel crossover behavior in reduced dimensions. We measure the anticlinic coupling between tilted surface layers in the smectic- A phase.
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Affiliation(s)
- C Y Chao
- Department of Physics and Astronomy, National Central University, Chung-Li 32054, Taiwan, Republic of China.
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Yang KD, Chao CY, Shaio MF. Pentoxifylline synergizes with all-trans retinoic acid to induce differentiation of HL-60 myelocytic cells, but suppresses tRA-augmented clonal growth of normal CFU-GM. Acta Haematol 2000; 99:191-9. [PMID: 9644296 DOI: 10.1159/000040838] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
All-trans retinoic acid (tRA) has been shown to promote terminal differentiation of promyelocytic leukemia cells, but frequently induce hyperleukocytosis and pulmonary leakage syndrome. Employing pentoxifylline (PTX), a phosphodiesterase inhibitor which could raise intracellular cAMP and modulate leukocyte activation, we sought to investigate if PTX could enhance tRA-induced promyelocytic leukemic cell differentiation but suppress tRA-augmented growth and activation of human granulocytes. tRA could significantly suppress clonal growth of U937 and HL-60 leukemic cells but enhanced the CFU-GM formation of normal bone marrow cells (22 +/- 6 vs. 90 +/- 16 CFU/well). PTX significantly augmented tRA suppression of clonal growth of U937 and HL-60 leukemic cells but suppressed tRA-augmented CFU-GM formation of normal bone marrow cells (90 +/- 16 vs. 25 +/- 9 CFU/well). In addition, PTX enhanced tRA-induced growth inhibition and differentiation of promyelocytic HL-60 leukemic cells, but suppressed respiratory burst activation by the immature granulocytic HL-60 cells and suppressed CD11b adhesion molecule expression by mature granulocytes. PTX similar to dibutyric cAMP promoted HL-60 myelocytic leukemic cell differentiation and growth inhibition, whereas PTX, in contrast to dibutyric cAMP which could augment phorbol myristate acetate (PMA)-elicited respiratory burst activity by immature granulocytes, suppressed the PMA-elicited respiratory burst activity by immature and mature granulocytes. PTX did not raise the intracellular cAMP level of HL-60 cells, but partly suppressed the dibutyric cAMP-elicited elevation of intracellular cAMP level. Results from these studies suggest that PTX might act through different signaling pathways to enhance tRA-induced myelocytic leukemic cell differentiation but prevent from hyperreactive normal granulopoiesis and granulocyte activation.
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Affiliation(s)
- K D Yang
- Chang Gung Children's Hospital at Kaohsiung, Taiwan
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Abstract
The presence of heavy metals (Cr, Cd, Pb and Zn) in feedstock increases the partitioning of polycyclic aromatic hydrocarbons (PAHs) in the solid as well as in the gaseous phases, which has been reported in our previous study. However, the partitioning of PAHs in air-pollution control equipment (APCE) has not been investigated thus far. Hence, the present work was conducted to study the partitioning of PAHs in APCE and the effect of heavy metals on PAHs formation by varying the target heavy metals in the feedstock.A fluidized bed incineration system which includes a primary combustion chamber (sand bed), a secondary combustion chamber (freeboard), and an APCE (cyclone and scrubber) was utilized in this study. The feedstock that contained various heavy metals was fed into the incinerator, and then the PAHs in the cyclone and scrubber were analyzed to determine the effect of heavy metals on PAHs partitioning. The results indicate that the presence of Pb and Zn in feedstock facilitates the formation of PAHs.
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Affiliation(s)
- M Y Wey
- Department of Environmental Engineering, National Chung-Hsing University, 40227, Taichung, Taiwan, ROC.
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Chao CY, Pan TC, Chou CF, Ho JT. Structural characterization of surface hexatic behavior in free-standing 4O.8 liquid-crystal films. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 2000; 62:R1485-R1488. [PMID: 11088709 DOI: 10.1103/physreve.62.r1485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2000] [Indexed: 05/23/2023]
Abstract
Electron diffraction in free-standing liquid-crystal films of N-(4-n-butoxybenzylidene)-4-n-octylaniline between 3 and 12 molecular layers thick reveals the unusual occurrence of the smectic-A' phase, a highly correlated isotropic liquid, on the surface of smectic-A films. The surface smectic-A-smectic-A' transition is found to be first order. Surprisingly, the temperature range of the subsequent surface hexatic-B phase is reduced with decreasing film thickness.
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Affiliation(s)
- CY Chao
- Department of Physics, National Central University, Chung-Li, Taiwan 32054, Republic of China
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Chao CY, Lo CR, Ho JT. Crystalline transitions in free-standing films of 4-n-heptyloxybenzylidene-4-n-heptylaniline. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 2000; 61:5407-5409. [PMID: 11031591 DOI: 10.1103/physreve.61.5407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 02/03/2000] [Indexed: 05/23/2023]
Abstract
Free-standing films of 4-n-heptyloxybenzylidene-4-n-heptylaniline are known to exhibit multiple smectic-I surface layers in the presence of a smectic-A interior. The phase transitions leading to the crystallization of these films have been studied using electron diffraction. Our data are consistent with the scenario of the smectic-I surface layers first developing a crystal-B outermost layer before transforming entirely into the crystal-B phase, to be followed by the freezing of the smectic-A interior. The adjacent crystal-B and smectic-I layers show evidence of orientational epitaxy.
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Affiliation(s)
- CY Chao
- Department of Physics, National Central University, Chung-Li, Taiwan, Republic of China
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Chao CY, Yeh SL, Lin MT, Chen WJ. Effects of parenteral infusion with fish-oil or safflower-oil emulsion on hepatic lipids, plasma amino acids, and inflammatory mediators in septic rats. Nutrition 2000; 16:284-8. [PMID: 10758365 DOI: 10.1016/s0899-9007(99)00299-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This study was designed to investigate the effects of preinfusion with total parenteral nutrition (TPN) using fish-oil (FO) versus safflower-oil (SO) emulsion as fat sources on hepatic lipids, plasma amino-acid profiles, and inflammatory-related mediators in septic rats. Normal rats, with internal jugular catheters, were assigned to two different groups and received TPN. TPN provided 300 kcal. kg(-1). d(-1), with 40% of the non-protein energy as fat. All TPN solutions were isonitrogenous and identical in nutrient composition except for the fat emulsion, which was made of SO or FO. After receiving TPN for 6 d, each group of rats was further divided into control and sepsis subgroups. Sepsis was induced by cecal ligation and puncture; control rats received sham operation. All rats were classified into four groups as follows: FO control group (FOC; n = 7), FO sepsis group (FOS; n = 8), SO control group (SOC; n = 8), and SO sepsis group (SOS; n = 9). The results of the study demonstrated that plasma concentrations of triacylglycerol and non-esterified fatty acids did not differ between the FO and SO groups, regardless of whether the animals were septic. SOS had significantly higher total lipids and cholesterol content in the liver than did the SOC group. The FOS group, however, showed no difference from the FOC group. Plasma leucine and isoleucine levels were significantly lower in the SOS group than in the SOC group, whereas no difference in these two amino acids was observed between the FOC and FOS groups. Plasma arginine levels were significantly lower in both septic groups than in the groups without sepsis when either FO or SO was infused. Plasma glutamine levels, however, did not differ across groups. No differences in interleukin-1beta, interleukin-6, tumor necrosis factor-alpha, or leukotriene B(4) concentrations in peritoneal lavage fluid were observed between the two septic groups. These results suggest that catabolic reaction in septic rats preinfused with FO is not as obvious as those preinfused with SO. Compared with SO emulsion, TPN with FO emulsion prevents liver fat accumulation associated with sepsis. However, parenterally administered FO had no beneficial effect in lowering cytokines and LTB(4) levels in peritoneal lavage fluid in septic rats induced by cecal ligation and puncture.
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Affiliation(s)
- C Y Chao
- Institute of Nutrition and Health Science, Taipei Medical College, Taipei, Taiwan, People's Republic of China
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Abstract
A series of measurements were conducted to study the indoor radon pollution in air-conditioned high-rise office buildings. Continuous monitoring of indoor radon levels in nine air-conditioned premises located in six office buildings in Hong Kong was conducted from August 1996 to February 1998. Each of the tests lasted for at least 48 hours. The measurement covered both day time monitoring while the air-conditioning was on and night time monitoring while the air-conditioning was off. The indoor radon level followed inversely the operation pattern of the mechanical ventilation systems in the buildings. During office hours when the mechanical ventilation was on, the indoor radon level decayed and after the mechanical ventilation was off during non-office hours, the radon level increased. The average indoor radon level during office hours on the nine premises varied from 87 Bq/m3 to 296 Bq/m3, and the indoor averaged radon levels over both day time and night time periods without mechanical ventilation were about 25 percent higher. The air infiltration rate and the radon emission characteristics from the building materials were estimated from the radon build-up curves which were observed after the mechanical ventilation was off. The radon decay curve observed after the mechanical ventilation system was turned on was used to calculate the total fresh air intake rate. Average radon emanation rates of the building materials in the six buildings varied from 0.0019 to 0.0033 Bq/m2s. It has been found that building infiltration rate accounted for about 10-30 percent of the total building ventilation rate in the buildings depending on building tightness.
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Affiliation(s)
- C Y Chao
- Department of Mechanical Engineering, Hong Kong University of Science and Technology, Hong Kong
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Chao CY, Tung TC. Radon emanation of building material--impact of back diffusion and difference between one-dimensional and three-dimensional tests. Health Phys 1999; 76:675-681. [PMID: 10334584 DOI: 10.1097/00004032-199906000-00011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Small-scale chamber experiments were conducted to investigate the radon emanation rates of commonly used building materials such as bare concrete, granite, red brick, and sand brick. It has been found that back diffusion caused by the accumulation of radon in the indoor environment has significant influence on the radon emanation rate. The radon emanation rate can be expressed as the summation of an initial emanation rate and the product of a specific back diffusion coefficient and the indoor radon level. In some occasions the radon emanation rate can be significantly lower than its initial value. A database was developed summarizing results from 26 samples. The influence of relative humidity on the radon emanation characteristics has also been discussed. Separate tests were done by coating the four sides of the building material with silicone gel to simulate a one-dimensional radon diffusion geometry. The results show that a factor has to be included when the three-dimensional test results are used to describe one-dimensional geometry, such as radon emanation from building wall surfaces.
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Affiliation(s)
- C Y Chao
- Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay
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Abstract
Heavy metal and polycyclic aromatic hydrocarbons (PAHs) in flue gas have received considerable attention in recent years due to their mutagenic or carcinogenic properties. The present study is carried out to investigate the influence of the quantity of heavy metals on PAHs formation in fly ash. A fluidized bed incinerator was used in this experiment to obtain fly ash of chemical similarity by incinerating various compositions of waste. The obtained fly ash, both with and without heavy metal, were used to adsorb the PAHs in the flue gas and to investigate the formation of PAHs in fly ash. The results indicate that carbon and heavy metals most greatly influence the formation of PAHs in the fly ash. Carbon is absorptive; heavy metals encourage not only absorption of PAHs but also catalyze PAHs formation.
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Affiliation(s)
- M Y Wey
- Department of Environmental Engineering, Chung-Hsing University, Taichung, Taiwan R.O.C
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Chao CY, Chou CF, Ho JT, Hui SW, Jin A, Huang CC. Nature of Layer-by-Layer Freezing in Free-Standing 4O.8 Films. Phys Rev Lett 1996; 77:2750-2753. [PMID: 10062036 DOI: 10.1103/physrevlett.77.2750] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Chao CY, Chuang SL. Momentum-space solution of exciton excited states and heavy-hole-light-hole mixing in quantum wells. Phys Rev B Condens Matter 1993; 48:8210-8221. [PMID: 10007012 DOI: 10.1103/physrevb.48.8210] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Fox AM, Miller DA, Cunningham JE, Jan WY, Chao CY, Chuang SL. Suppression of the observation of Stark ladders in optical measurements on superlattices by excitonic effects. Phys Rev B Condens Matter 1992; 46:15365-15376. [PMID: 10003654 DOI: 10.1103/physrevb.46.15365] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Chao CY, Chuang SL. Spin-orbit-coupling effects on the valence-band structure of strained semiconductor quantum wells. Phys Rev B Condens Matter 1992; 46:4110-4122. [PMID: 10004141 DOI: 10.1103/physrevb.46.4110] [Citation(s) in RCA: 113] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Chao CY, Chuang SL. Resonant tunneling of holes in the multiband effective-mass approximation. Phys Rev B Condens Matter 1991; 43:7027-7039. [PMID: 9998166 DOI: 10.1103/physrevb.43.7027] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Chao CY, Chuang SL. Analytical and numerical solutions for a two-dimensional exciton in momentum space. Phys Rev B Condens Matter 1991; 43:6530-6543. [PMID: 9998093 DOI: 10.1103/physrevb.43.6530] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Abstract
This paper reports a pathological and immunohistochemical study of gastric carcinoma for immunoreactivity with a monoclonal antibody. MGD-1, raised against cells from an adenocarcinoma of stomach. Fifty-four of 61 gastric carcinomas (89%) were positive for MGD-1. Metastatic gastric carcinoma in local nodes was positive in all 11 such cases. Out of 40 examples of chronic atrophic gastritis, only three, with mild dysplasia, were positive (7.5%). Forty cases with normal gastric mucosa were negative. The MGD-1 detection-rate of well- and poorly-differentiated gastric carcinoma was 85% and 93% respectively. The metastatic cells and cells infiltrating the submucosa and muscular layer were more frequently positive and showed stronger staining with MGD-1 than those in mucosa. These results show that MGD-1 possesses a high degree of specificity for gastric carcinoma and could be used diagnostically.
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Affiliation(s)
- C Y Chao
- Department of Pathology, 4th Military Medical College, Xian, People's Republic of China
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Tsay SS, Tsay HS, Chao CY. Cytochemical studies of callus development from microspore in cultured anther of rice. Plant Cell Rep 1986; 5:119-123. [PMID: 24248049 DOI: 10.1007/bf00269249] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/1985] [Revised: 01/13/1986] [Indexed: 06/02/2023]
Abstract
Cytochemical studies of androgenic anthers of Oryza sativa picked from the culture at 2 day intervals from 0 to 40 days have been carried out. Glutaradehyde-OsO4-fixed and plastic-embedded sections were stained with TBO, SBB and PAS for acidic polymers, lipids and polysaccharides respectively. Among the population only 4% of microspores, which accumulate abundant amorphous lipid in the first few days of culture, are androgenic. Less than 30%, which have many lipid granules and some amorphous lipid, become nutritive microspores. Starch grains also accumulate in these nutritive microspores which degenerate at the stage when the androgenic multicellular microspores are in rapid development. The remaining microspores, which have no or little lipid, degenerate early. At about the 100-cell stage, each multicellular unit consists of two cell types, large and small. The large cells contain abundant amorphous lipid and starch grains which the small ones stain intensely with TBO.Our results indicate that the epidermis and endothecium of the cultured anthers are not quiescent. They can accumulate and transport lipid and polysaccharides at certain stages during the cultural period. Globular embryoid appearing structures and leaf-like protrusions can be observed at the surface of the callus in about 40-day old culture, indicating that both embryogenesis and organogenesis may take place in rice callus.
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Affiliation(s)
- S S Tsay
- Department of Biology, Tunghai University, 400, Taichung, Taiwan, ROC
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Wood PA, Herman GE, Chao CY, O'Brien WE, Beaudet AL. Retrovirus-mediated gene transfer of argininosuccinate synthetase into cultured rodent cells and human citrullinemic fibroblasts. Cold Spring Harb Symp Quant Biol 1986; 51 Pt 2:1027-32. [PMID: 3472748 DOI: 10.1101/sqb.1986.051.01.118] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Abstract
The effects of ginsenosides Rg1 and Rb1 of Panax ginseng on mitosis in the onion root tip cells as well as on the rate of DNA synthesis in onion seedlings were studied. Results obtained from the concentration and time course study in bulb and seeding root tip cells indicate that Rg1 promotes and Rb1 inhibits mitosis, both being dose-dependent. The promoting effect of Rg1 on the rate of DNA synthesis was observed at the peak hour which occurs at the same time as that of the control. Rb1 was found to shift the peak hour of DNA synthesis to a later period of the experiment. These results are in agreement with the results obtained from the study of the cell cycle by pulse labeling and autoradiography, which show that Rg1 shortens the mitotic cell cycle and S period while Rb1 lengthens them. They in turn increase and decrease the mitotic indices respectively.
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Abstract
The ginsenoside Rg1 extracted from the root of Panax ginseng can promote mitosis in cultured human lymphocytes activated by PHA or Con A. Its most effective concentrations are around 0.0003-0.0005 mg per ml of medium. Experiments show that it does not arrest the cells at any particular mitotic stage. It can also enhance the DNA synthesis in the activated lymphocytes. As a result of the increased number of the mitotic cells and enhanced DNA synthesis, the cell density is significantly increased in the Rg1-treated culture as compared with the control. However, in the absence of a mitogenic lectin Rg1 cannot restart the quinescent human lymphocytes to divide in vitro; therefore it is not mitogenic to resting cells. The possible action of Rg1 on activated human lymphocytes as well as its pharmacological significance are discussed.
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Han CS, Chao CY. The relationship between leucoagglutinin and febrile transfusion reactions in hematologic patients. Chin Med J 1965; 84:804-8. [PMID: 5864050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Affiliation(s)
- C Y Chao
- Department of Botany, National Taiwan University, Taipei, Taiwan, China
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