Publications by authors named "Chen-Yu Chang"

43 Publications

Sulvanites: The Promise at the Nanoscale.

Nanomaterials (Basel) 2021 Mar 23;11(3). Epub 2021 Mar 23.

Department of Mechanical and Materials Engineering, Florida International University, Miami, FL 33199, USA.

The class of ternary copper chalcogenides CuMX (M = V, Nb, Ta; X = S, Se, Te), also known as the sulvanite family, has attracted attention in the past decade as featuring promising materials for optoelectronic devices, including solar photovoltaics. Experimental and theoretical studies of these semiconductors have provided much insight into their properties, both in bulk and at the nanoscale. The recent realization of sulvanites at the nanoscale opens new avenues for the compounds toward printable electronics. This review is aimed at the consideration of synthesis methods, relevant properties and the recent developments of the most important sulvanites.
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http://dx.doi.org/10.3390/nano11030823DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8005093PMC
March 2021

Femtosecond time-evolution of mid-infrared spectral line shapes of Dirac fermions in topological insulators.

Sci Rep 2020 Jun 17;10(1):9803. Epub 2020 Jun 17.

Department of Electrophysics, National Chiao Tung University, Hsinchu, Taiwan.

Mid-infrared (MIR) light sources have much potential in the study of Dirac-fermions (DFs) in graphene and topological insulators (TIs) because they have a low photon energy. However, the topological surface state transitions (SSTs) in Dirac cones are veiled by the free carrier absorption (FCA) with same spectral line shape that is always seen in static MIR spectra. Therefore, it is difficult to distinguish the SST from the FCA, especially in TIs. Here, we disclose the abnormal MIR spectrum feature of transient reflectivity changes (ΔR/R) for the non-equilibrium states in TIs, and further distinguish FCA and spin-momentum locked SST using time-resolved and linearly polarized ultra-broadband MIR spectroscopy with no environmental perturbation. Although both effects produce similar features in the reflection spectra, they produce completely different variations in the ΔR/R to show their intrinsic ultrafast dynamics.
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http://dx.doi.org/10.1038/s41598-020-66720-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7299937PMC
June 2020

Heat dissipation in quasi-ballistic single-atom contacts at room temperature.

Sci Rep 2019 Dec 10;9(1):18677. Epub 2019 Dec 10.

Department of Electrophysics, National Chiao Tung University, 1001 University Road, Hsinchu, 30010, Taiwan.

We report on evaluations of local heating in Au single-atom chains at room temperature. We performed onsite thermometry of atomic-scale Au junctions under applied sinusoidal voltage of variable amplitudes. The AC approach enabled to preclude electromigration effects for characterizing the influence of energy dissipations on the lifetime. We elucidated nonlinear increase in the effective temperature of the current-carrying single-atom chains with the voltage amplitudes, which was attributed to subtle interplay between electron-phonon scattering and electron-mediated thermal transport in the quasi-ballistic conductor. We also found that only 0.2% of the electric power contributed to local heating while the majority was consumed at the diffusive bank. The present findings can be used for thermal management of future integrated nanoelectronics.
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http://dx.doi.org/10.1038/s41598-019-55048-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6904740PMC
December 2019

A curvature-tunable random laser.

Nanoscale 2019 Feb;11(8):3534-3545

Institute of Electro-Optical Science and Technology, National Taiwan Normal University, 88, Sec.4, Ting-Chou Road, Taipei 116, Taiwan.

The application of random lasers has been restricted due to the absence of a well-defined resonant cavity, as the lasing action mainly depends on multiple light scattering induced by intrinsic disorders of the laser medium to establish the required optical feedback that hence increases the difficulty in efficiently tuning and modulating random lasing emissions. This study investigated whether the transport mean free path of emitted photons within disordered scatterers composed of ZnO nanowires is tunable by a curvature bending applied to the flexible polyethylene terephthalate (PET) substrate underneath, thereby creating a unique light source that can be operated above and below the lasing threshold for desirable spectral emissions. For the first time, the developed curvature-tunable random laser is implemented for in vivo biological imaging with much lower speckle noise compared to the non-lasing situation through simple mechanical bending, which is of great potential for studying the fast-moving physiological phenomenon such as blood flow patterns in mouse ear skin. It is expected that the experimental demonstration of the curvature-tunable random laser can provide a new route to develop disorder-based optoelectronic devices.
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http://dx.doi.org/10.1039/c8nr09153fDOI Listing
February 2019

Continuance compliance of privacy policy of electronic medical records: the roles of both motivation and habit.

BMC Med Inform Decis Mak 2018 12 18;18(1):135. Epub 2018 Dec 18.

Department of Family Medicine, E-Da Hospital, Kaohsiung City, Taiwan, Republic of China.

Background: Hospitals have increasingly realized that wholesale adoption of electronic medical records (EMR) may introduce differential tangible/intangible benefits to them, including improved quality-of-care, reduced medical errors, reduced costs, and allowable instant access to relevant patient information by healthcare professionals without the limitations of time/space. However, an increased reliance on EMR has also led to a corresponding increase in the negative impact exerted via EMR breaches possibly leading to unexpected damage for both hospitals and patients. This study investigated the possible antecedents that will influence hospital employees' continuance compliance with privacy policy of Electronic Medical Records (EMR). This is done from both motivational and habitual perspectives; specifically, we investigated the mediating role of habit between motivation and continuance compliance intention with EMR privacy policy.

Methods: Data was collected from a large Taiwanese medical center by means of survey methodology. A total of 312 responses comprised of various groups of healthcare professionals was collected and analyzed via structural equation modeling.

Results: The results demonstrated that self-efficacy, perceived usefulness, and facilitating conditions may significantly predict hospital employees' compliance habit formation, whereas habit may significantly predict hospital employees' intention to continuance adherence to EMR privacy policy. Further, habit partially mediates the relationships between self-efficacy, perceived usefulness, facilitating conditions and continuance adherence intention.

Conclusions: Based on our findings, the study suggests that healthcare facilities should take measures to promote their employees' habitualization with continuous efforts to protect EMR privacy parameters. Plausible strategies include improving employees' levels of self-efficacy, publicizing the effectiveness of on-going privacy policy, and creating a positive habit-conducive environment leading to continued compliance behaviors.
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http://dx.doi.org/10.1186/s12911-018-0722-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6299633PMC
December 2018

High-Content Screening of a Taiwanese Indigenous Plant Extract Library Identifies leaf Extract as an Inhibitor of Fatty Acid Uptake.

Int J Mol Sci 2018 Jul 22;19(7). Epub 2018 Jul 22.

Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.

Non-alcoholic fatty liver disease (NAFLD) has become the most common liver disease in the recent decades in both developed and developing countries, and is predicted to be the major etiology for liver transplantation in the next decade. Thus, pharmacological strategies to treat NAFLD are urgently needed. Natural products are considered an excellent source for drug discovery. By utilizing an image-based high-throughput screening with a library containing 3000 Taiwanese indigenous plant extracts, we discovered that the extract of leaves (SSLE) has an anti-lipid droplet (LD) accumulation effect in hepatic cell lines. Analyses of the expression profile of genes involved in lipid metabolism revealed that SSLE suppressed the mRNA expression of , fatty acid translocase. In agreement with this observation, we showed that SSLE inhibited CD36 protein expression and fatty acid uptake and has only limited effects on pre-formed LDs. Moreover, SSLE reduced LD accumulation and expression in enterocyte and macrophage cell lines. In conclusion, our findings suggest that SSLE could serve as a potential source for the discovery of novel therapeutic modalities for NAFLD and that the suppression of expression and fatty acid uptake could contribute to the lipid-lowering effect of SSLE.
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http://dx.doi.org/10.3390/ijms19072130DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6073993PMC
July 2018

A Flavone Constituent from Myoporum bontioides Induces M-Phase Cell Cycle Arrest of MCF-7 Breast Cancer Cells.

Molecules 2017 Mar 15;22(3). Epub 2017 Mar 15.

Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan.

Myoporum bontioides is a traditional medicinal plant in Asia with various biological activities, including anti-inflammatory and anti-bacterial characteristics. To identify the bioactive constituents from M. bontioides, a newly-identified flavone, 3,4'-dimethoxy-3',5,7-trihydroxyflavone (compound 1), along with eight known compounds, were investigated in human MCF-7 breast cancer, SCC4 oral cancer, and THP-1 monocytic leukemia cells. Among these compounds, compound 1 exhibited the strongest antiproliferative activity with half-maximal inhibitory concentration (IC) values ranging from 3.3 μM (MCF-7) to 8.6 μM (SCC4). Flow cytometric analysis indicated that compound 1 induced G2/M cell cycle arrest in MCF-7 cells. Mechanistic evidence suggests that the G2/M arrest could be attributable to compound 1's modulatory effects on the phosphorylation and expression of numerous key signaling effectors, including cell division cycle 2 (CDC2), CDC25C, and p53. Notably, compound 1 downregulated the expression of histone deacetylase 2 (HDAC2) and HDAC4, leading to increased histone H3 acetylation and p21 upregulation. Together, these findings suggest the translational potential of compound 1 as a breast cancer treatment.
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http://dx.doi.org/10.3390/molecules22030472DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6155216PMC
March 2017

Band-Engineered Local Cooling in Nanoscale Junctions.

Sci Rep 2017 02 15;7:42647. Epub 2017 Feb 15.

Department of Electrophysics, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan.

The stability and performance of nanoscale junctions are closely related to the local effective temperature. The local effective temperature is mainly caused by the competition between heating and cooling processes in inelastic electron-phonon scat- tering. Local cooling occurs when the rate of energy in cooling exceeds that in heating. Previous research has been done using either specific potential configuration or an adatom to achieve local cooling. We propose an engineer-able local-cooling mechanism in asymmetric two-terminal tunneling junctions, in which one electrode is made of metal, whereas the other is made of a selectable bad-metal, such as heavily-doped polysilicon. The width of energy window of the selectable material, defined as the width covering all possible energy states counting from the conduction band minimum, can be engineered through doping. Interestingly, we have shown that substantial local cooling can be achieved at room temperature when the width of energy window of the low-density electrode is comparable to the energy of the phonon. The unusual local cooling is caused by the narrowed width of energy window, which obstructs the inelastic scattering for heating.
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http://dx.doi.org/10.1038/srep42647DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5309743PMC
February 2017

[Effects of Different Culture Systems on the Hematopoietic Differentiation Ability of iPS Cells].

Zhongguo Shi Yan Xue Ye Xue Za Zhi 2016 Dec;24(6):1863-1868

The Third Hospital Affiliated to Guangzhou Medical University,Key Laboratory for Major Obstetric Diseases of Guangdong Province,Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes,Guangzhou 510150, Guangdong Province, China.

Objective: To investigate the in vitro effects of different culture systems on hematopoietic differentiation ability of induced pluripotent stem (iPS) cells.

Method: Two culture systems including E8 and mTESR(freeder-free medium), and the classical ES culture medium were chosen for culture of iPS cells. The iPS cells maintaining in above mentioning culcure systems were co-cultured with OP9 cells(murine bone marrow stromal cells) in vitro to be induced to differentiate into hematopoietic stem/progenitor cells. Flow cytometry and real-time quantitative PCR were used to detect the expression of specific hematopoietic markers and the effects of different culture systems on the differentiation of iPS in vitro.

Result: iPS cultured in the 3 selected medium could be differentiated into hematopoietic stem cells. Efficiency of hematopoietic differentiation was up to 28.4% in classical ES culture system, which was significantly higher than that in E8 and mTESR system.

Conclusion: Under the co-culture with OP9, iPS can differentiate into hematopoietic stem/progenitor cells, which shows higher efficiency when iPS maintained in the ES medium.
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http://dx.doi.org/10.7534/j.issn.1009-2137.2016.06.045DOI Listing
December 2016

Volatile compounds from roots, stems and leaves of Angelica acutiloba growing in Taiwan.

Nat Prod Commun 2014 Apr;9(4):583-6

The present study analyzed and compared the volatile compounds in fresh Angelica acutiloba roots, stems and leaves both qualitatively and quantitatively. The volatile compounds were isolated by either steam distillation (SD) or headspace-solid phase microextraction (HS-SPME). A total of 61 compounds were identified using gas chromatography/mass spectrometry (GC/MS). All 61 compounds were verified by SD, with 3n-butyl phthalide, gamma-terpinene, p-cymene and cis-beta-ocimene as the main compounds. Thirty-three compounds were verified by HS-SPME, with gamma-terpinene and p-cymene as the main compounds. The leaf samples contained the highest essential oil content. Compared with SD, HS-SPME sampling resulted in relatively higher amounts of highly volatile monoterpenes and lower amounts of less volatile compounds such as 3n-butyl phthalide. These findings demonstrate that A. acutiloba roots, stems and leaves have high 3n-butyl phthalide contents; thus, all parts of A. acutiloba may be used for further application and development.
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April 2014

Programmable redox state of the nickel ion chain in DNA.

Nano Lett 2014 Feb 23;14(2):1026-31. Epub 2014 Jan 23.

Department of Biological Science and Technology, National Chiao Tung University , 75 Bo Ai Street, Hsinchu, Taiwan , 30068.

DNA is a nanowire in nature which chelates Ni ions and forms a conducting chain in its base-pairs (Ni-DNA). Each Ni ion in Ni-DNA exhibits low (Ni(2+)) or high (Ni(3+)) oxidation state and can be switched sequentially by applying bias voltage with different polarities and writing times. The ratio of low and high oxidation states of Ni ions in Ni-DNA represents a programmable multistate memory system with an added capacitive component, in which multistate information can be written, read, and erased. This study also indicates that the biomolecule-based self-organized nanostructure can be used as a template for nanodevice fabrication.
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http://dx.doi.org/10.1021/nl404601sDOI Listing
February 2014

Inhibitory effects of cultured Dendrobium tosaense on atopic dermatitis murine model.

Int J Pharm 2014 Mar 16;463(2):193-200. Epub 2013 Aug 16.

Department of Agronomy, National Chung-Hsing University, Taichung 40227, Taiwan; Department and Graduate Institute of Applied Chemistry, Chaoyang University of Technology, Wufeng 41349, Taiwan. Electronic address:

Dendrobium tosaense is one of the most valuable Chinese medicines and well developed health food. Atopic dermatitis (AD) is a chronic skin disease that occurs mainly in childhood. The pathogenesis of atopic dermatitis had been studied in BALB/c mice modeling by skin-inoculated ovalbumin (OVA) with 2,4,6-trinitro-1-chrolobenzene (TNCB). These mice exhibit features of chronic dermatitis, including skin rash, mast cells infiltration, and elevated serum anti-OVA specific IgE and cytokines modulation. In this study, a standardized ethyl acetate extract of D. tosaense (DtE) was used to protect these mice from the OVA/TNCB-induced skin lesions of atopic dermatitis. The results indicated an increased population of natural T regulatory cell was accompanied by immunosuppression in cytokine profiles and anti-OVA IgE level to significantly reduce Th2 polarization. Finally, toluidine blue staining indicated mast cell infiltration and degranulation was reduced in skin lesion. Our results were shed light on the usage of D. tosaense in AD.
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http://dx.doi.org/10.1016/j.ijpharm.2013.08.015DOI Listing
March 2014

Anti-inflammatory components from the root of Solanum erianthum.

Int J Mol Sci 2013 Jun 14;14(6):12581-92. Epub 2013 Jun 14.

Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, College of Pharmacy, China Medical University, Taichung 404, Taiwan.

Two new norsesquiterpenoids, solanerianones A and B (1-2), together with nine known compounds, including four sesquiterpenoids, (-)-solavetivone (3), (+)-anhydro-β-rotunol (4), solafuranone (5), lycifuranone A (6); one alkaloid, N-trans-feruloyltyramine (7); one fatty acid, palmitic acid (8); one phenylalkanoid, acetovanillone (9), and two steroids, β-sitosterol (10) and stigmasterol (11) were isolated from the n-hexane-soluble part of the roots of Solanum erianthum. Their structures were elucidated on the basis of physical and spectroscopic data analyses. The anti-inflammatory activity of these isolates was monitored by nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine macrophage RAW264.7 cells. The cytotoxicity towards human lung squamous carcinoma (CH27), human hepatocellular carcinoma (Hep 3B), human oral squamous carcinoma (HSC-3) and human melanoma (M21) cell lines was also screened by using an MTT assay. Of the compounds tested, 3 exhibited the strongest NO inhibition with the average maximum inhibition (Emax) at 100 μM and median inhibitory concentration (IC50) values of 98.23% ± 0.08% and 65.54 ± 0.18 μM, respectively. None of compounds (1-9) was found to possess cytotoxic activity against human cancer cell lines at concentrations up to 30 μM.
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http://dx.doi.org/10.3390/ijms140612581DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3709801PMC
June 2013

The effect of the aerial part of Lindera akoensis on lipopolysaccharides (LPS)-induced nitric oxide production in RAW264.7 cells.

Int J Mol Sci 2013 Apr 26;14(5):9168-81. Epub 2013 Apr 26.

Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, China Medical University, Taichung 404, Taiwan.

Four new secondary metabolites, 3α-((E)-Dodec-1-enyl)-4β-hydroxy-5β-methyldihydrofuran-2-one (1), linderinol (6), 4'-O-methylkaempferol 3-O-α-L-(4''-E-p-coumaroyl)rhamnoside (11) and kaempferol 3-O-α-L-(4''-Z-p-coumaroyl)rhamnoside (12) with eleven known compounds-3-epilistenolide D1 (2), 3-epilistenolide D2 (3), (3Z,4α,5β)-3-(dodec-11-ynylidene)-4-hydroxy-5-methylbutanolide (4), (3E,4β,5β)-3-(dodec-11-ynylidene)-4-hydroxy-5-methylbutanolide (5), matairesinol (7), syringaresinol (8), (+)-pinoresinol (9), salicifoliol (10), 4''-p-coumaroylafzelin (13), catechin (14) and epicatechin (15)-were first isolated from the aerial part of Lindera akoensis. Their structures were determined by detailed analysis of 1D- and 2D-NMR spectroscopic data. All of the compounds isolated from Lindera akoensis showed that in vitro anti-inflammatory activity decreases the LPS-stimulated production of nitric oxide (NO) in RAW 264.7 cell, with IC50 values of 4.1-413.8 µM.
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http://dx.doi.org/10.3390/ijms14059168DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3676778PMC
April 2013

Anti-inflammatory lanostanoids and lactone derivatives from Antrodia camphorata.

J Nat Prod 2013 Apr 21;76(4):489-94. Epub 2013 Mar 21.

Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan.

Four new lanostanoids, ethyl lucidenate A (1), ethyl lucidenate F (2), 15-O-acetylganolucidate A (3), and 3,11,15,23-tetraoxo-27ξ-lanosta-8,16-dien-26-oic acid (4), and two new lactone derivatives, 5-hydroxy-5-(methoxymethyl)-4-methylfuran-2(5H)-one (5) and 3-(4-methoxy-2-oxo-2H-pyran-6-yl)propanoic acid (6), together with four known compounds, 11α-hydroxy-3,7-dioxolanost-8,24(E)-dien-26- oic acid (7), 3,7,11-trioxo-5α-lanosta-8,24(E)-dien-26-oic acid (8), methyl 3,7,11,12,15,23-hexaoxo-5α-lanost-8-en-26-oate (9), and ethyl 3,7,11,12,15,23-hexaoxo-5α-lanost-8-en-26-oate (10), were characterized from Antrodia camphorata. The structures of these new compounds were determined by analysis of their spectroscopic data, including 1D and 2D NMR experiments. Ten components were evaluated for anti-inflammatory activity by examining their effect on LPS-iNOS-dependent NO production in murine macrophage (RAW 264.7) cells. Among them, compounds 1, 3, 7, 8, 9, and 10 significantly suppressed the NO concentration in LPS-treated RAW 264.7 cells with IC50 values ≤ 10 μM.
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http://dx.doi.org/10.1021/np300443pDOI Listing
April 2013

New Anti-Inflammatory Aromatic Components from Antrodia camphorata.

Int J Mol Sci 2013 Feb 26;14(3):4629-39. Epub 2013 Feb 26.

Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, College of Pharmacy, China Medical University, Taichung 404, Taiwan.

Three new benzenoids, 3-isopropenyl-2-methoxy-6-methyl-4,5-methylenedioxy- phenol (1), 2-hydroxy-4,4'-dimethoxy-3,3'-dimethyl-5,6,5',6'-bimethylenedioxybiphenyl (2), 4,4'-dihydroxy-3,3'-dimethoxy-2,2'-dimethyl-5,6,5',6'-bimethylenedioxybiphenyl (3), together with two known benzenoids, 2,3,6-trimethoxy-5-methylphenol (4) and 2,3-methylenedioxy- 4-methoxy-5-methylphenol (5), were isolated from Antrodia camphorata. Our results support that compounds 1-5 potently inhibited LPS (lipopolysaccharide)-induced nitric oxide (NO) production in a dose-dependent manner. The IC(50) values of compounds 1, 3 and 5 were 1.8 ± 0.2, 18.8 ± 0.6 and 0.8 ± 0.3 μg/mL, respectively.
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http://dx.doi.org/10.3390/ijms14034629DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3634465PMC
February 2013

Diterpenoids with anti-inflammatory activity from the wood of Cunninghamia konishii.

Molecules 2013 Jan 4;18(1):682-9. Epub 2013 Jan 4.

Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, College of Pharmacy, China Medical University, Taichung 404, Taiwan.

Two new diterpenoids, konishone (1) and 3b-hydroxy-5,6-dehydrosugiol (2), along with three known diterpenoids--hinokiol (3), sugiol (4), and 12-hydroxy-6,7-secoabieta-8,11,13-triene-6,7-dial (5)--were isolated from the wood of Cunninghamia konishii. Compound 1 is a novel skeleton of the 7,20-dinorabietane-type diterpene. In addition, when RAW264.7 macrophages were treated with different concentrations of compounds 1, 3, and 5 together with LPS, a significant concentration-dependent inhibition of NO production was detected. The IC₅₀ values for inhibition of nitrite production of compounds 1, 3, and 5 were about 9.8 ± 0.7, 7.9 ± 0.9, and 9.3 ± 1.3 μg/mL, respectively. This study presents the potential utilization of compounds 1, 3, and 5, as lead compounds for the development of anti-inflammatory drugs.
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http://dx.doi.org/10.3390/molecules18010682DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6269968PMC
January 2013

[Investigation on snails Achatina fulica and Pomacea canaliculata infected with Angiostrongylus cantonensis in Panyu region of Guangzhou City].

Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi 2012 Jun;24(3):336-8

The Third Clinical Medical College, Guangzhou Medical College, Guangzhou 510182, China.

Objective: To understand the natural infection status of Angiostrongylus cantonensis in snails Achatina fulica and Pomacea canaliculata from Panyu region of Guangzhou City.

Methods: The snails Achatina fulica and Pomacea canaliculata captured from the field were digested with the artificial stomach fluid. The third-stage larvae of A. cantonensis were examined and counted under a microscope. The collected third-stage larvae were used to infect SD rats.

Results: A total of 367 Achatina fulica and 357 Pomacea canaliculata were examined. The infection rate of A. cantonensis in Achatina fulica was 22.62%, with a mean intensity of 57.00 larvae per positive snail. The infection rate of A. cantonensis in Pomacea canaliculata was 3.08%, with a mean intensity of 1.64 larvae per positive snail. The infection rates of A. cantonensis in Achatina fulica from Dagang, Shiqi, Hualong, and Lanhe towns and Nansha District, were 13.33%, 15.00%, 20.93%, 73.68% and 8.41%, respectively. Those in Pomacea canaliculata were 5.88%, 2.88%, 1.89%, 0% and 3.96%, respectively.

Conclusions: A. cantonensis infection exists in Achatina fulica and Pomacea canaliculata from Panyu region of Guangzhou City, and the infection in Achatina fulica is more serious than that in Pomacea canaliculata. The infection rates of the snails among five sites are different.
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June 2012

Lanostane triterpenoids and sterols from Antrodia camphorata.

Phytochemistry 2012 Dec 18;84:177-83. Epub 2012 Sep 18.

Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, China Medical University, Taichung 404, Taiwan.

Four lanostane triterpenes, 3,7,11-trioxo-5α-lanosta-8,24(E)-dien-26-oic acid, methyl 11α-3,7-dioxo-5α-lanosta-8,24(E)-dien-26-oate, methyl 3,7,11,12,15,23-hexaoxo-5α-lanost-8-en-26-oate, and ethyl 3,7,11,12,15,23-hexaoxo-5α-lanost-8-en-26-oate, two sterols, (14α,22E)-14-hydroxyergosta-7,22-diene-3,6-dione and a steroid named as camphosterol A were isolated from a mixture of fruiting bodies and mycelia of solid cultures of Antrodia camphorata. The ¹H and ¹³C NMR spectra of all compounds were fully assigned using a combination of 2D NMR experiments, including COSY, HMQC, HMBC and NOESY sequences. Six compounds were evaluated for cytotoxicity against several human tumor cell lines, all of which has moderate activity.
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http://dx.doi.org/10.1016/j.phytochem.2012.08.011DOI Listing
December 2012

Berberine, an isoquinoline alkaloid, inhibits the metastatic potential of breast cancer cells via Akt pathway modulation.

J Agric Food Chem 2012 Sep 14;60(38):9649-58. Epub 2012 Sep 14.

Department of Biological Science and Technology, China Medical University, Taichung, Taiwan.

Berberine (BBR) is a natural alkaloid with significant antitumor activities against many types of cancer cells. In this study, we investigated the molecular mechanisms by which BBR repressed the metastatic potential of breast cancer cells. BBR was found to downregulate the enzymatic activities and expression levels of matrix metalloproteinases 2 and 9 (MMP2 and MMP9, respectively). The BBR-mediated suppression of MMP2 and MMP9 involved the inhibition of the Akt/nuclear factor kappa B (NF-κB) and activator protein-1 (AP-1) signaling pathways. Furthermore, BBR repressed the expression of the Akt protein by modulating the mRNA expression level and protein degradation of Akt. In conclusion, this study suggests that BBR can reduce the metastatic potential of highly metastatic breast cancer cells and may be a useful adjuvant therapeutic agent in the treatment of breast cancer by targeting the Akt pathway.
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http://dx.doi.org/10.1021/jf302832nDOI Listing
September 2012

A new butanolide compound from the aerial part of Lindera akoensis with anti-inflammatory activity.

Molecules 2012 May 31;17(6):6585-92. Epub 2012 May 31.

School of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, China Medical University, Taichung 404, Taiwan.

A new butanolide, 3β-((E)-dodec-1-enyl)-4β-hydroxy-5β-methyldihydrofuran-2-one (1) and four known butanolides: Akolactone A (2), (3Z,4α,5β)-3-(dodec-11-enylidene)-4-hydroxy-5-methylbutalactone (3), (3E,4α,5β)-3-(dodec-11-enylidene)-4-hydroxy-5-methylbutalactone (4) and dihydroisoobtusilactone (5), were isolated from the aerial parts of Lindera akoensis. These butanolides showed in vitro anti-inflammatory activity decrease the LPS-stimulated production of nitrite in RAW264.7 cell, with IC₅₀ values of 1.4-179.9 μM.
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http://dx.doi.org/10.3390/molecules17066585DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6268235PMC
May 2012

Effect of electron-vibration interactions on the thermoelectric efficiency of molecular junctions.

Nanotechnology 2012 Jul 18;23(27):275401. Epub 2012 Jun 18.

Department of Electrophysics, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan.

From first-principles approaches, we investigate the thermoelectric efficiency of a molecular junction where a benzene molecule is connected directly to the platinum electrodes. We calculate the thermoelectric figure of merit ZT in the presence of electron-vibration interactions with and without local heating under two scenarios: linear response and finite bias regimes. In the linear response regime, ZT saturates around the electrode temperature T(e) = 25 K in the elastic case, while in the inelastic case we observe a non-saturated and a much larger ZT beyond T(e) = 25 K attributed to the tail of the Fermi-Dirac distribution. In the finite bias regime, the inelastic effects reveal the signatures of the molecular vibrations in the low-temperature regime. The normal modes exhibiting structures in the inelastic profile are characterized by large components of atomic vibrations along the current density direction on top of each individual atom. In all cases, the inclusion of local heating leads to a higher wire temperature T(w) and thus magnifies further the influence of the electron-vibration interactions due to the increased number of local phonons.
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http://dx.doi.org/10.1088/0957-4484/23/27/275401DOI Listing
July 2012

Peroxisome proliferator-activated receptor gamma (PPAR-γ) and neurodegenerative disorders.

Mol Neurobiol 2012 Aug 21;46(1):114-24. Epub 2012 Mar 21.

Neuroscience Division, Institute of Biomedical Sciences, Academia Sinica, Rm 404, Taipei 11529, Taiwan, Republic of China.

As the growth of the aging population continues to accelerate globally, increased prevalence of neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), and stroke, has generated substantial public concern. Unfortunately, despite of discoveries of common factors underlying these diseases, few drugs are available to effectively treat these diseases. Peroxisome proliferator-activated receptor gamma (PPAR-γ) is a ligand-activated transcriptional factor that belongs to the nuclear hormone receptor superfamily. PPAR-γ has been shown to influence the expression or activity of a large number of genes in a variety of signaling networks, including regulation of insulin sensitivity, glucose homeostasis, fatty acid oxidation, immune responses, redox balance, cardiovascular integrity, and cell fates. Recent epidemiological, preclinical animal, and clinical studies also show that PPAR-γ agonists can lower the incidence of a number of neurological disorders, despite of multiple etiological factors involved in the development of these disorders. In this manuscript, we review current knowledge on mechanisms underlying the beneficial effect of PPAR-γ in different neurodegenerative diseases, in particular, AD, PD, and stroke, and attempt to analyze common and overlapping features among these diseases. Our investigation unveiled information suggesting the ability for PPAR-γ to inhibit NF-κB-mediated inflammatory signaling at multiple sites, and conclude that PPAR-γ agonists represent a novel class of drugs for treating neuroinflammatory diseases.
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http://dx.doi.org/10.1007/s12035-012-8259-8DOI Listing
August 2012

Stroke, angiogenesis and phytochemicals.

Front Biosci (Schol Ed) 2012 Jan 1;4:599-610. Epub 2012 Jan 1.

Institute of Neuroscience, National Yang-Ming University, Taipei, Taiwan, ROC.

Stroke, or brain attack, is the third leading cause of death and the leading cause of adult disability worldwide. There is a great demand for intervention therapy. Unfortunately, although more than 700 drugs that target neuroprotection showed beneficial effects in preclinical animal studies, none of them proved efficacious in treating stroke patients. There is recent interest in understanding mechanism for post-ischemic angiogenesis in the penumbra area, and correlation of the extent of angiogenesis with survival in stroke patients. It is postulated that besides replenishing oxygen and nutrients to ischemic tissue, angiogenesis may play a crucial role in neural protection and tissue recovery. Consequently, therapeutic agents to promote angiogenesis and formation of new vessels after stroke can offer promising approach. Several large population epidemiological and clinical studies have revealed a reciprocal relationship between intake of phytochemicals and incidence of stroke. However, the detailed cellular and molecular mechanisms leading to these beneficial effects remain to be elucidated. In this article, we review the current knowledge on phytochemicals and post-ischemic angiogenesis, and discuss the possibility of a combinatorial treatment, including neuroprotection, angiogenesis, neurogenesis, and phytochemicals regimen for stroke.
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http://dx.doi.org/10.2741/s287DOI Listing
January 2012

Antioxidant activities of aqueous leaf extracts of Toona sinensis on free radical-induced endothelial cell damage.

J Ethnopharmacol 2011 Sep 28;137(1):669-80. Epub 2011 Jun 28.

Institute of Nutrition, China Medical University, Taichung, Taiwan.

Ethnopharmacological Relevance: In Taiwan, Toona sinensis (Toona sinensis) is well known as a traditional Chinese medicine, while the underlying pharmacological mechanisms of this drug are still a matter of debate.

Materials And Methods: The purpose of this study was to evaluate the protective effects of non-cytotoxic concentrations of aqueous leaf extracts of Toona sinensis (TS extracts; 50-100 μg/mL) and gallic acid (5 μg/mL), a major component of these extracts, against AAPH-induced oxidative cell damage in human umbilical vein endothelial cells (ECs).

Results: Exposure of ECs to AAPH (15 mM) decreased cell viability from 100% to 43%. However, ECs were pre-incubated with TS extracts prior to AAPH induction resulted in increased resistance to oxidative stress and cell viability in a dose-dependent manner. An increase in ECs-derived PGI(2) and IL-1 β in response to AAPH exposure was positively correlated with cytotoxicity and negatively with TS extracts concentrations. In addition, gallic acid also suppressed PGI(2) and IL-1 β production in AAPH-induced ECs. Notably, TS extracts/gallic acid treatment significantly inhibited ROS generation, MDA formation, SOD/catalase activity, and Bax/Bcl-2 dysregulation in AAPH-stimulated ECs. Pretreatment of ECs with TS extracts/gallic acid also suppressed AAPH-induced cell surface expression and secretion of VCAM-1, ICAM-1 and E-selectin, which was associated with abridged adhesion of U937 leukocytes to ECs. Moreover, TS extracts/gallic acid treatment significantly inhibited the AAPH-mediated up regulation of PAI-1 and down regulation of t-PA in ECs, which may decrease fibrinolytic activity.

Conclusions: Therefore, Toona sinensis may possess antioxidant properties that protect endothelial cells from oxidative stress. Our results also support the traditional use of Toona sinensis in the treatment of free radical-related diseases and atherosclerosis.
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http://dx.doi.org/10.1016/j.jep.2011.06.017DOI Listing
September 2011

Clarification of the phenotypic characteristics and anti-tumor activity of Hedyotis diffusa.

Am J Chin Med 2011 ;39(1):201-13

School of Pharmacy, China Medical University, Taichung, Taiwan.

Hedyotis diffusa Willd. (Rubiaceae) is an important folk herb used to prevent and cure hepatitis and liver cancer in Taiwan. For differentiation of H. diffusa from counterfeits, macroscopic and microscopic characters of H. diffusa, H. corymbosa and H. tenelliflora were examined in this study. According to Trypan blue exclusion assay and Western blot analysis, H. diffusa had a significant inhibition of cell growth and induction of cell apoptosis in COLO 205 (colon cancer), Hep 3B (hepatocellular carcinoma) and H460 (lung cancer) cell lines. This study also used high-performance liquid chromatography (HPLC) to determine the quality control of H. diffusa. The HPLC data showed that ursolic and oleanolic acid are the components of the H. diffusa, consisting of approximately 4.66-4.80% and 1.86-1.96%, respectively. Our study also demonstrated that ursolic acid has significant anti-tumor activity in COLO 205, Hep 3B and H460 cancer cells.
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http://dx.doi.org/10.1142/S0192415X11008750DOI Listing
April 2011

Anti-apoptotic actions of PPAR-gamma against ischemic stroke.

Mol Neurobiol 2010 Jun 3;41(2-3):180-6. Epub 2010 Feb 3.

Neuroscience Division, Institute of Biomedical Sciences, Academia Sinica, Rm 404, Taipei, Taiwan, Republic of China.

Stroke is a leading cause of adult disability and mortality. Diabetes is a major risk factor for stroke. Patients with diabetes have a higher incidence of stroke and a poorer prognosis after stroke. Peroxisome proliferator-activated receptor gamma (PPAR-gamma) is a ligand-modulated transcriptional factor and a therapeutic target for treating type II diabetes. It is well-documented that activation of PPAR-gamma can also attenuate postischemic inflammation and damage. In this review, we focus on the newly revealed anti-apoptotic actions of PPAR-gamma against cerebral ischemia. PPAR-gamma, by increasing superoxide dismutase/catalase and decreasing nicotinamide adenine dinucleotide phosphate oxidase levels, attenuated ischemia-induced reactive oxygen species and subsequently alleviated the postischemic degradation of Bcl-2, Bcl-xl, and Akt. The preserved Akt phosphorylated Bad. Meanwhile, PPAR-gamma also promotes the transcription of 14-3-3epsilon. Elevated 14-3-3epsilon binds and sequesters p-Bad and prevents Bad translocation to neutralize the anti-apoptotic function of Bcl-2. This review further supports the notion that PPAR-gamma may serve as a potential therapeutic target for treating ischemic stroke.
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http://dx.doi.org/10.1007/s12035-010-8103-yDOI Listing
June 2010

Thermoelectric efficiency in nanojunctions: a comparison between atomic junctions and molecular junctions.

ACS Nano 2009 Nov;3(11):3497-504

Department of Electrophysics, National Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu, Taiwan.

Using first-principles approaches, we investigate the thermoelectric efficiency, characterized by the figure of merit ZT, in metallic atomic junctions and insulating molecular junctions. To gain insight into the properties of ZT, an analytical theory is also developed to study the dependence of ZT on lengths (l) and temperatures (T). The theory considers the combined heat current carried by electrons and phonons. We observe a characteristic temperature: T(0) = (beta/gamma(/))(1/2). When T << T(0), the electronic heat current dominates the combined heat current and ZT is proportional to T(2). When T >> T(0), the phononic heat current dominates the combined heat current and ZT tends to a saturation value. Moreover, the metallic atomic junctions and the insulating molecular junctions have opposite trend for the dependence of ZT on lengths, that is, ZT increases as the length increases for aluminum atomic junctions, while ZT decreases as the length increases for alkanethiol molecular junctions.
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http://dx.doi.org/10.1021/nn900986rDOI Listing
November 2009

Optimal degradation of dye wastewater by ultrasound/Fenton method in the presence of nanoscale iron.

Water Sci Technol 2009 ;60(5):1295-301

Department of Medical Imaging and Radiological Sciences, Central Taiwan University of Science and Technology, Takun, Taichung, Chinese Taiwan.

An advanced ultrasound/Fenton/nanoscale iron oxidation process was applied for treatment of dye wastewater. In this study, the Taguchi statistical method was used to design experiments for the optimization of the ultrasound/Fenton/nanoscale iron process. The experimental design consisted of testing five factors (dosage of H(2)O(2), concentration of Fe(2 + ), amount of nanoscale iron added, treatment time, and initial pH), with four levels of each factor tested. Chemical oxygen demand (COD) measurements were conducted to determine the efficiency of the water samples. An analysis of the mean sign-to-noise (S/N) ratio indicated that the optimum combination of levels of the factors providing maximal COD reduction of aqueous azo dyes (500 mg/L) were: treatment time = 60 min, dosage of nanoscale iron = 1 g/L, initial pH = 2, and ratio of [dye]:[H(2)O(2)]:[Fe(2 + )]=1:3.6:2.4. The efficiencies of decolorization and COD reduction were accomplished under these optimum conditions at levels of 99.91% and 63.36%, respectively. The percentage contribution of each factor was determined by the analysis of variance (ANOVA). The results show that the contributions of the five factors-dosage of H(2)O(2), concentration of Fe(2 + ), amount of nanoscale iron added, treatment time, and initial pH-were 29.33%, 21.37%, 22.51%, 12.93% and 12.35%, respectively.
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http://dx.doi.org/10.2166/wst.2009.366DOI Listing
October 2009

Ligand-activated peroxisome proliferator-activated receptor-gamma protects against ischemic cerebral infarction and neuronal apoptosis by 14-3-3 epsilon upregulation.

Circulation 2009 Mar 16;119(8):1124-34. Epub 2009 Feb 16.

Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.

Background: Thiazolidinediones have been reported to protect against ischemia-reperfusion injury. Their protective actions are considered to be peroxisome proliferator-activated receptor-gamma (PPAR-gamma)-dependent; however, it is unclear how PPAR-gamma activation confers resistance to ischemia-reperfusion injury.

Methods And Results: We evaluated the effects of rosiglitazone or PPAR-gamma overexpression on cerebral infarction in a rat model and investigated the antiapoptotic actions in the N2-A neuroblastoma cell model. Rosiglitazone or PPAR-gamma overexpression significantly reduced infarct volume. The protective effect was abrogated by PPAR-gamma small interfering RNA. In mice with knock-in of a PPAR-gamma dominant-negative mutant, infarct volume was enhanced. Proteomic analysis revealed that brain 14-3-3epsilon was highly upregulated in rats treated with rosiglitazone. Upregulation of 14-3-3epsilon was abrogated by PPAR-gamma small interfering RNA or antagonist. Promoter analysis and chromatin immunoprecipitation revealed that rosiglitazone induced PPAR-gamma binding to specific regulatory elements on the 14-3-3epsilon promoter and thereby increased 14-3-3epsilon transcription. 14-3-3epsilon Small interfering RNA abrogated the antiapoptotic actions of rosiglitazone or PPAR-gamma overexpression, whereas 14-3-3epsilon recombinant proteins rescued brain tissues and N2-A cells from ischemia-induced damage and apoptosis. Elevated 14-3-3epsilon enhanced binding of phosphorylated Bad and protected mitochondrial membrane potential.

Conclusions: Ligand-activated PPAR-gamma confers resistance to neuronal apoptosis and cerebral infarction by driving 14-3-3epsilon transcription. 14-3-3epsilon Upregulation enhances sequestration of phosphorylated Bad and thereby suppresses apoptosis.
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http://dx.doi.org/10.1161/CIRCULATIONAHA.108.812537DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4144045PMC
March 2009
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