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Kuo WH, Chen HL, Hsiao CK, Chuang EY, Chang KJ. Abstract P6-04-03: Unique Recurrent Signature and Signaling Pathway of Asian Triple Negative Breast Cancer. Cancer Res 2010. [DOI: 10.1158/0008-5472.sabcs10-p6-04-03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Triple-negative (TN) breast cancer, a lack of understanding of the driving oncogenic mechanisms and thus therapeutic targets has left this an understudied ‘Cinderella’ in breast cancer phase III trials. No publication has been addressed on recurrent signature and pathway signaling of Asia TN breast cancer. The gene expression difference between Eastern and Western breast cancer is also unknown.
Material and Methods: 185 represent breast cancer cases including 43 Luminal A, 31 Luminal B, 35 Her-2 type, 51 TN and remaining 25 unclassified were selected from our tissue bank. Using Agilent microarray chip, we explored gene expression profile of these patients. For direct western and eastern comparison, 195 Caucasian breast cancer gene expression profile using the same Agilent platform were downloaded wedsite. In TN breast cancers, excluding 3 cases with stage IV disease at diagnosis, 11 patients developed distant recurrence during follow up. For these 48 patients, recurrent model was established by two step Cox proportional hazard regression: in first step, 35 candidate recurrent genes were selected from 20173 genes with significant level less than 0.0005. Then, we randomly choose 4 genes from the 35 candidate genes to construct recurrent model to avoid overfitting. TN related signaling pathways were discovered using Ingenuity Pathway Analysis(IPA) and GSEA(Gene Set Enrichment Analysis).
Results: Using non-supervised analysis, we found the eastern and western breast cancers have their own TN cancer clustering phenomenon, obviously in a different cluster.
This represented the eastern and western breast cancer have fundamental differences. The model including PKRAG3, MORC2, GRB7, FAM43A showed the best recurrence prediction power in 52360 combination models(R Square 0.71). This model was cross-validated by Vector machine(SVM) with leave one out setting. The overall accuracy was 87.5%. The sensitivity and specificity were 72.7% and 91.9%. This model was failed to predict recurrence in Luminal or Her-2 Molecular type. With IPA, we found 9 TN related pathway. The top two were cAMP-mediated and Ephrin Receptor signaling. 10 pathways were found from GSEA. Nicotinate, Olfactory transduction and Axon guidance were on the top of the list. Further functional study is on going.
Discussion: This is the first study to compare the gene expression between eastern and western breast cancer on the same gene expression platform. The gene expression profile is fundamentally different between eastern and western TN breast cancers. This phenomenon infers different biological behavior and drug sensitivity may exist among different ethnic groups. We established recurrent prediction model unique for Taiwanese TN breast cancer by four genes with high accuracy. We can develop commercial recurrent kit after further clinical validation.
Figure available in online version.
Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-04-03.
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Chang JW, Ou HY, Chen HL, Guo HR, Liao PC, Lee CC. Interrelationship between exposure to PCDD/Fs and hypertension in metabolic syndrome in Taiwanese living near a highly contaminated area. CHEMOSPHERE 2010; 81:1027-1032. [PMID: 20850865 DOI: 10.1016/j.chemosphere.2010.08.050] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 08/14/2010] [Accepted: 08/27/2010] [Indexed: 05/29/2023]
Abstract
Metabolic syndrome (MetS) consists of a constellation of metabolic abnormalities that confer increased risk of cardiovascular disease. There is a positive correlation between exposure to persistent organic pollutants and MetS. We examine the association between PCDD/Fs and MetS components in 1490 non-diabetic persons living near a highly dioxin-contaminated area. We used factor analysis, with a set of core variables considered central features of MetS and PCDD/Fs, to group similar risk factors. Serum PCDD/Fs were positively and significantly correlated with the number of MetS components. Four risk factors-lipidemia, blood pressure, body size, and glycemia-accounted for 72.6% of the variance in the 10 core factors, and PCDD/Fs were linked to MetS through shared correlations with high blood pressure. After adjusting for confounding factors, we found that diastolic blood pressure (β=0.018; p=0.006), glucose (β=0.013; p=0.046), and waist circumference (β=0.721; p=0.042) significantly increased with increasing serum PCDD/F levels. We found significant trends for associations between metabolic syndrome and serum low-chlorinated PCDD/Fs. The highest quintiles of 2,3,4,7,8-PeCDF, 1,2,3,6,7,8-HxCDF and 2,3,7,8-TCDD had the top three adjusted ORs (95% CI) of 3.5 (1.9-6.3), 2.9 (1.7-4.9) and 2.8 (1.6-4.9), respectively. We also found a slight monotonic relationship between serum PCDD/Fs and the prevalence of MetS, especially when the serum dioxin level was higher than 25.4pg WHO(98)-TEQ(DF)g(-1) lipid (the fourth Quintile). We hypothesize that high-dose exposure to PCDD/Fs is a blood pressure-related factor that raises MetS risk.
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Lee YC, Tseng SC, Chen HL, Yu CC, Cheng WL, Du CH, Lin CH. Using autocloning effects to develop broad-bandwidth, omnidirectional antireflection structures for silicon solar cells. OPTICS EXPRESS 2010; 18 Suppl 3:A421-A431. [PMID: 21165072 DOI: 10.1364/oe.18.00a421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this study, we used the autocloning effect on pyramid structures to develop broad-bandwidth, omnidirectional antireflection structures for silicon solar cells. The angular dependence of reflectance on several pyramid structures was systematically investigated. The deposition of three-layer autocloned films reduced the refractive index gap between air and silicon, resulting in an increase in the amount of transmitted light and a decrease in the total light escaping. The average reflectance decreased dramatically to ca. 2-3% at incident angles from 0 to 60° for both sub-wavelength- and micrometer-scale pyramid structures. The measured reflectance of the autocloned structure was less than 4% in the wavelength range from 400 to 1000 nm for incident angles from 0 to 60°. Therefore, the autocloning technique, combined with optical thin films and optical gradient structures, is a practical and compatible method for the fabrication of broad-bandwidth, omnidirectional antireflection structures on silicon solar cells.
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Tsao GSW, Tsang CM, Zhang GT, Deng W, Hau PM, Man CM, Kenzo T, Chen HL, Yip YL, Lo KW, Cao Y, Cheung LM. Abstract 2460: Epstein-Barr virus infection confer stress-resistant property in immortalized nasopharyngeal epithelial cells. Cancer Res 2010. [DOI: 10.1158/1538-7445.am10-2460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Epstein-Barr virus (EBV) infection has been postulated to be an early event involved in the pathogenesis of NPC. The lack of representative premalignant nasopharyngeal epithelial cell system for EBV infection has hampered research investigation into the regulation and involvement of EBV infection in NPC pathogenesis. We have compared the efficiency of EBV infection in nasopharyngeal epithelial cells with different biological properties including immortalized, primary and cancerous nasopharyngeal epithelial cells. EBV infection could be achieved in all the nasopharyngeal epithelial cells examined with variable infection rate. TGF-β effectively enhanced EBV infection into nasopharyngeal epithelial cells both in the immortalized and primary nasopharyngeal epithelial cells. Stable infection of EBV was achieved in a telomerase-immortalized nasopharyngeal epithelial cell line, NP460hTert. The expression pattern of EBV-encoded genes and biological properties of this EBV infected cell line upon long term propagation were monitored. The EBV-infected nasopharyngeal epithelial cells acquired anchorage independent growth in soft-agar and exhibited invasive growth properties upon prolonged propagation. A distinguish feature of this EBV-infected nasopharyngeal epithelial cell model was its enhanced ability to survive under growth factor and nutrient starvation. This was evidenced by the suppressed activation of apoptotic markers and sustained activation of pAkt of EBV-infected cells compared to control cells under nutrient starvation. Examination of cytokine profiles of EBV-infected NP460hTert cells to nutrient and growth factor deprivation revealed upregulation expression of MCP-1 and GRO-α. The establishment of a stable EBV infection model of premalignant nasopharyngeal epithelial cells will facilitate research investigation into the pathogenic role of EBV in NPC development.
Acknowlegement: The authors wish to acknowlege the funding support from the Research Grant Council (Hong Kong) and the Area of Excellence on Nasopharyangeal Carcinoma Research Center (Hong Kong).
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2460.
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Yang L, Shi Q, Ho DJ, Starkov AA, Wille EJ, Xu H, Chen HL, Zhang S, Stack CM, Calingasan NY, Gibson GE, Beal MF. Mice deficient in dihydrolipoyl succinyl transferase show increased vulnerability to mitochondrial toxins. Neurobiol Dis 2009; 36:320-30. [PMID: 19660549 DOI: 10.1016/j.nbd.2009.07.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 07/08/2009] [Accepted: 07/28/2009] [Indexed: 11/24/2022] Open
Abstract
The activity of a key mitochondrial tricarboxylic acid cycle enzyme, alpha-ketoglutarate dehydrogenase complex (KGDHC), declines in many neurodegenerative diseases. KGDHC consists of three subunits. The dihydrolipoyl succinyl transferase (DLST) component is unique to KGDHC. DLST(+/-) mice showed reduced mRNA and protein levels and decreased brain mitochondrial KGDHC activity. Neurotoxic effects of mitochondrial toxins were exacerbated in DLST(+/-) mice. MPTP produced a significantly greater reduction of striatal dopamine and tyrosine hydroxylase-positive neurons in the substantia nigra pars compacta of DLST(+/-) mice. DLST deficiency enhanced the severity of lipid peroxidation in the substantia nigra after MPTP treatment. Striatal lesions induced by either malonate or 3-nitropropionic acid (3-NP) were significantly larger in DLST(+/-) mice than in wildtype controls. DLST deficiency enhanced the 3-NP inhibition of mitochondria enzymes, and 3-NP induced protein and DNA oxidations. These observations support the hypothesis that reductions in KGDHC may impair the adaptability of the brain and contribute to the pathogenesis of neurodegenerative diseases.
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Rothschild MF, Lie WR, Chen HL, Warner CM, Christian LL. Genetic variability at the pig SLA complex in U.S. breeds of pigs. ANIMAL BLOOD GROUPS AND BIOCHEMICAL GENETICS 2009; 14:251-5. [PMID: 6675485 DOI: 10.1111/j.1365-2052.1983.tb01082.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Lymphocytes from 90 mature pigs and 548 growing pigs from 65 litters were screened with cytotoxic antibodies against swine lymphocyte antigens. Pigs included in the survey were from the Chester White, Duroc, Hampshire, Landrace and Yorkshire breeds. Significant differences between breeds were found in the frequency of the three haplotypes tested. Such differences may provide the genetic variability needed to determine associations between disease susceptibility and the pig's major histocompatibility gene complex.
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Chen HL, Chuang SY, Lee WH, Kuo SS, Su WF, Ku SL, Chou YF. Extraordinary transmittance in three dimensional crater, pyramid, and hole-array structures prepared through reversal imprinting of metal films. OPTICS EXPRESS 2009; 17:1636-1645. [PMID: 19188993 DOI: 10.1364/oe.17.001636] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We used a reversal imprinting-in-metal (RIM) process to fabricate various three-dimensional (3D) metal structures under low pressure. Molds featuring different shapes were used to pattern various subwavelength metal structures, including pyramidal, hole-array, and crater-like structures. Refractive index matching and cavity effects both enhanced the degree of transmission of these structured metal films. The crater-like structure appears to be a promising material because of the unique properties imparted by the elongated and gradually tapering spacing of its cavities. From both near-field simulations and experimentally obtained optical spectra, we found that the cavity effect in the crater-like structure led to significantly enhanced transmission of the optical intensity. Thus, this RIM process allows the ready fabrication of various two- and three-dimensional metallic structures for use in surface plasmon-based devices.
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Chang Chien SW, Chen HL, Wang MC, Seshaiah K. Oxidative degradation and associated mineralization of catechol, hydroquinone and resorcinol catalyzed by birnessite. CHEMOSPHERE 2009; 74:1125-1133. [PMID: 19028396 DOI: 10.1016/j.chemosphere.2008.10.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2008] [Revised: 10/10/2008] [Accepted: 10/14/2008] [Indexed: 05/27/2023]
Abstract
Abiotic degradation and mineralization of catechol, hydroquinone, and resorcinol catalyzed by birnessite (delta-MnO2) was investigated. Studies were carried out by monitoring changes of pE versus time and pH versus time of the reaction systems during the initial 10 h reaction period and release of CO2 and associated reactions at the end of a 90 h reaction period. The reactions under anoxic condition were compared with aeration condition. The reactions were carried out in suspensions at initial pH of 6.0 under air and N2 atmosphere at room temperature and free of microbial activity. These results indicated that kinetic-related changes of pE versus time and pH versus time were dependent on structural characteristics of phenolic compound and aeration or anoxic condition in the reaction system. The sequence of the mineralization of phenolic compounds catalyzed by delta-MnO2 in presence of air expressed by CO2 release was catechol > hydroquinone > or = resorcinol and the differences were significant. However, under an N2 atmosphere the amounts of CO2 released were drastically reduced with insignificant differences among the three reaction systems. Further, phenolic compound degradations, dissolved and adsorbed Mn, and oxidation state of Mn in delta-MnO2 were also determined to elucidate the catalytic efficacy mediated by both O2 and delta-MnO2 in the reaction systems.
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Chen HL, Hsieh KC, Lin CH, Chen SH. Using direct nanoimprinting of ferroelectric films to prepare devices exhibiting bi-directionally tunable surface plasmon resonances. NANOTECHNOLOGY 2008; 19:435304. [PMID: 21832691 DOI: 10.1088/0957-4484/19/43/435304] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this paper, we describe an imprint method for the fabrication of bi-directionally tunable surface plasmon resonance (SPR) filters. A periodic metal/ferroelectric film stack exhibiting SPR phenomena was directly imprinted using a sharp mold without the need for a polymer-based resist. Both the refractive index of the surrounding lead zirconate titanate (PZT) films and the period of the textured PZT/metal/PZT structure were dependent upon both the absolute value and sign of the applied potential. The SPR wavelength of the PZT/gold/PZT-based tunable filter varied over a range of greater than 100 nm when applying potentials ranging from 0 to -15 V. This imprinting method has great potential for use in the fabrication of tunable optical filters without the need for complicated processes or specific materials.
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Gao ZQ, Yang C, Wang YY, Wang P, Chen HL, Zhang XD, Liu R, Li WL, Qin XJ, Liang X, Hai CX. RAGE upregulation and nuclear factor-kappaB activation associated with ageing rat cardiomyocyte dysfunction. Gen Physiol Biophys 2008; 27:152-158. [PMID: 18981529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Evidence suggests that ageing is a major risk factor for cardiac dysfunction. Interactions between advanced glycation endproducts (AGEs) and the receptor for AGEs (RAGE) are known to cause chronic cellular activation, including activation of nuclear factor-kappaB (NF-kappaB), which has been implicated as a causal factor in the ageing process. To assess whether cardiomyocyte contractile function and the interaction of AGEs with RAGE in the heart are altered in ageing, 25- and 2-month-old male rats were compared. Mechanical properties were assessed in ventricular myocytes using an edge-detection system, including peak twitch amplitude (PTA), time-to-PTA (TPS), time-to-75% relengthening (TR75) and maximal velocity of shortening/relengthening (+/-dL/dt) in ventricular myocytes. AGEs were detected by using a fluorescence assay. The expression of RAGE and NF-kappaB was assessed through a Western blot analysis. Compared with young myocytes, aged myocytes displayed a prolonged TR75 at 1 Hz. With increasing stimulus frequency (from 2 to 4 Hz), aged myocytes' PTA was significantly reduced relative to young myocytes. Aged rat hearts displayed high level of AGEs, RAGE upregulation and NF-kappaB activation. These findings demonstrate impaired cardiomyocyte relaxation and reduced tolerance to increased stimulus frequency in aged rats, which might be associated with enhanced AGEs, RAGE expression, and NF-kappaB activation.
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Chuang SY, Chen HL, Kuo SS, Lai YH, Lee CC. Using direct nanoimprinting to study extraordinary transmission in textured metal films. OPTICS EXPRESS 2008; 16:2415-2422. [PMID: 18542320 DOI: 10.1364/oe.16.002415] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
In this paper, we describe a thermal embossing imprint method, which we name "nano-imprinting in metal" (NIM), for patterning metal films with a variety of profiles. Metal films exhibiting either perforated hole-arrays or corrugated structures with various surface morphologies can be fabricated rapidly. The SPR phenomenon allowed energy coupling to the other side of the textured metal film, causing a dramatic increase in the transmission. As a technique for readily controlling the working wavelength and transmittance, the NIM method has great potential for application in various optoelectronic devices.
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Chen HL, Su HJ, Hsu JF, Liao PC, Lee CC. High variation of PCDDs, PCDFs, and dioxin-like PCBs ratio in cooked food from the first total diet survey in Taiwan. CHEMOSPHERE 2008; 70:673-81. [PMID: 17692359 DOI: 10.1016/j.chemosphere.2007.06.059] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2007] [Revised: 06/21/2007] [Accepted: 06/24/2007] [Indexed: 05/16/2023]
Abstract
This study determined the levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), and dioxin-like polychlorinated biphenyls (dl-PCBs) in 240 individual food samples, belonging to 37 different foodstuffs in first total diet study (TDS) in Taiwan. The foods were collected from markets located in eight cities or counties around Taiwan. The food was cooked in a laboratory according to recipes typically used in Taiwan. In this study, PCDD/Fs were lower than the limits proposed by the European Union (EU) regulation for commercialized food, except for a notable PCDD/Fs level in ducks (3.660 pg WHO-TEQ/g, fat) obtained from central Taiwan. We hypothesize the duck meat might be probably polluted via emission of a fly ash recycling plant located near the duck farms. In addition to fish, most foods had high PCDD/Fs to dl-PCBs ratio. Needle fish and sea perch had relatively lower PCDD/Fs and dl-PCBs levels compared with those in other fish. Data from this study can be utilized for further consideration about dietary intake.
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Liu HH, Wu YC, Chen HL. Production of ozone and reactive oxygen species after welding. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2007; 53:513-8. [PMID: 17612781 DOI: 10.1007/s00244-007-0030-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Accepted: 05/06/2007] [Indexed: 05/16/2023]
Abstract
Many toxic substances including heavy metals, ozone, carbon monoxide, carbon dioxide, and nitrogen oxides are generated during welding. Ozone (O(3)) is a strong oxidant that generates reactive oxygen species (ROS) in tissue, and ambient ROS exposure associated with particles has been determined to cause DNA damage. Ozone is produced within 30 seconds during welding. However, the length of time that O(3) remains in the air after welding is completed (post-welding) is unknown. The current study aimed to assess the distributions of ambient ROS and O(3) before the start of welding (pre-welding), during welding, and after welding. The highest O(3) levels, equal to 195 parts per billion (ppb), appeared during welding. Ozone levels gradually decreased to 60 ppb 10 minutes after the welding was completed. The highest ROS level was found in samples taken during welding, followed by samples taken after the welding was completed. The lowest ROS level was found in samples taken before the welding had started. Ozone and ROS levels were poorly correlated, but a similar trend was found for O(3) and ROS levels in particles (microM/mg). Although particles were not generated after welding, ROS and O(3) still persisted for more than 10 minutes. Meanwhile, because O(3) continues after welding, how long the occupational protective system should be used depends on the welding materials and the methods used. In addition, the relationship between metal fumes and ROS generation during the welding process should be further investigated.
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Chen HL, Chuang SY, Lin CH, Lin YH. Using colloidal lithography to fabricate and optimize sub-wavelength pyramidal and honeycomb structures in solar cells. OPTICS EXPRESS 2007; 15:14793-14803. [PMID: 19550759 DOI: 10.1364/oe.15.014793] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The external quantum efficiency of solar cells can be improved by using texturing pyramid- and honeycomb-like structures with minimum reflection. In this study, we investigated the reflection properties of texturing structures through rigorous coupled-wave analysis and the three-dimensional finite-difference time domains (FDTD) method to analyze close-packed texturing structures. We also demonstrate a simple method-combining sub-wavelength-scale monolayer and bilayer polystyrene spheres with a one-step reactive ion etching process-to fabricate optimized pyramid- and honeycomb-shaped antireflection structures, respectively. Thus, sub-wavelength pyramidal and honeycomb-like structures displaying low reflectance were obtained readily without the need for any lithography equipment.
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Lin J, Yuan XC, Bu J, Chen HL, Sun YY, Burge RE. Generalized model for orbital angular momentum states generated by parallel aligned phase wedges. OPTICS LETTERS 2007; 32:2170-2. [PMID: 17671573 DOI: 10.1364/ol.32.002170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
A generalized model of a double-wedge phase element containing two side-by-side parallel phase ramps with arbitrary slope angles is proposed. We study the diffracted optical field of a double-wedge element in terms of orbital angular momentum states. Analytical calculations reveal how the radius and position of the illuminating laser beam affect the composition of orbital angular momentum generated by the phase wedges.
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Bano D, Munarriz E, Chen HL, Ziviani E, Lippi G, Young KW, Nicotera P. The plasma membrane Na+/Ca2+ exchanger is cleaved by distinct protease families in neuronal cell death. Ann N Y Acad Sci 2007; 1099:451-5. [PMID: 17446485 DOI: 10.1196/annals.1387.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Neurodegenerative conditions commonly involve loss of neuronal connectivity, synaptic dysfunction with excessive pruning, and ionic imbalances. These often serve as a prelude to cell death either through the activation of apoptotic or necrotic death routines or excess autophagy. In many instances, a local or generalized Ca2+ deregulation is involved in signaling or executing cell death. We have recently shown that in brain ischemia, and during excitotoxicity triggered by excess glutamate, the irreversible Ca2+ deregulation leading to necrosis is due to calpain-mediated modulation of the plasma membrane Na+/Ca2+ exchanger (NCX). Here we show that the NCX can also be cleaved by caspases in neurons undergoing apoptosis, which suggests that cleavage of the main Ca2+ extrusion pathway is a lethal event in multiple forms of cell death.
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Chen HL, Zou LY, Li JY, Wang XZ, Chen ZX, Huang YH. Dual suppression of cyclooxygenase-2 and 5-lipoxygenase inhibits proliferation and induces apoptosis of gastric cancer cell line AGS. Shijie Huaren Xiaohua Zazhi 2007; 15:323-331. [DOI: 10.11569/wcjd.v15.i4.323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To evaluate the efficacy of the selective cyclooxygenase-2 (COX-2) inhibitor nimesulide, 5-lipoxygenase (5-LOX) inhibitor AA861 and their combination on the proliferation and apoptosis of human gastric carcinoma cell line AGS.
METHODS: Human gastric carcinoma cell line AGS was cultured in RPMI1640 medium with 100 mL/L fetal bovine serum (FBS), 100 kU/L penicillin G and 100 kU/L streptomycin in an incubator at 37°C, with 100% humidity and 50 mL/L CO2. Then AGS cells were treated with AA861 (25, 50, 100 mmol/L) or nimesulide (50, 100, 200 mmol/L) or in combination. The morphological changes of AGS cells were observed and photographed by inverted microscopy. The proliferation of AGS cells was detected by thiazolyl blue tetrazolium bromide (MTT) assays. Acridineorange-ethidiumbromide (AO-EB) fluorescence staining, TUNEL staining and DNA-fragment assay were used to evaluate the apoptotic of AGS cells.
RESULTS: The morphological changes were observed in AGS cells treated by nimesulide, AA861 or their combination under the inverted microscope. MTT assay revealed that nimesulide and AA861 inhibited the proliferation of AGS cells in a dose- and time-dependent manner, except for nimesulide of 200 mmol/L at the 24th and 48th hour as well as AA861 of 25 mmol/L at the 24th hour. TUNEL staining showed that the apoptosis rate was elevated with the increase of nimesulide and AA861 concentration. MTT assay (AA861: 0.240 ± 0.002 vs combination: 0.207 ± 0.001, P < 0.01; nimesulide: 0.211 ± 0.002 vs combination: 0.207 ± 0.001, P < 0.05), AO-EB staining (AA861: 18.17% ± 0.28%, nimesulide: 19.35% ± 0.74% vs combination: 23.78% ± 0.04%, P < 0.01), TUNEL staining (AA861: 18.67% ± 0.03%, nimesulide: 20.94% ± 0.48% vs combination: 23.76% ± 0.92%, P < 0.01) and DNA-fragment assay showed that the combined treatment of AA861 and nimesulide was superior to AA861 or nimesulide alone in inhibiting the proliferation and inducing the apoptosis of AGS cells at the 48th hour.
CONCLUSION: Either COX-2 inhibitor nimesulide or 5-LOX inhibitor AA861 can inhibit the proliferation and induce the apoptosis of human AGS cells. The dual inhibition of COX-2 and 5-LOX may present a superior anticancer efficacy to either inhibition of COX-2 or 5-LOX alone.
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Lu TW, Hsu HC, Chang LY, Chen HL. Enhancing the examiner’s resisting force improves the reliability of manual muscle strength measurements: Comparison of a new device with hand-held dynamometry. J Rehabil Med 2007; 39:679-84. [DOI: 10.2340/16501977-0107] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Lee CC, Lin WT, Liao PC, Su HJ, Chen HL. High average daily intake of PCDD/Fs and serum levels in residents living near a deserted factory producing pentachlorophenol (PCP) in Taiwan: influence of contaminated fish consumption. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2006; 141:381-6. [PMID: 16213641 DOI: 10.1016/j.envpol.2005.08.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2004] [Accepted: 08/02/2005] [Indexed: 05/04/2023]
Abstract
An abandoned pentachlorophenol plant and nearby area in southern Taiwan was heavily contaminated by dioxins, impurities formed in the PCP production process. The investigation showed that the average serum PCDD/Fs of residents living nearby area (62.5 pg WHO-TEQ/g lipid) was higher than those living in the non-polluted area (22.5 and 18.2 pg WHO-TEQ/g lipid) (P<0.05). In biota samples, average PCDD/F of milkfish in sea reservoir (28.3 pg WHO-TEQ/g) was higher than those in the nearby fish farm (0.15 pg WHO-TEQ/g), and Tilapia and shrimp showed the similar trend. The average daily PCDD/Fs intake of 38% participants was higher than 4 pg WHO-TEQ/kg/day suggested by the world health organization. Serum PCDD/F was positively associated with average daily intake (ADI) after adjustment for age, sex, BMI, and smoking status. In addition, a prospective cohort study is suggested to determine the long-term health effects on the people living near factory.
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Wang Y, Gao JQ, Chen HL, Zheng CH, Liang WQ. Pluronic F127 gel effectively controls the burst release of drug from PLGA microspheres. DIE PHARMAZIE 2006; 61:367-8. [PMID: 16649559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
To investigate the controlled release effect of a thermo-sensitive gel, Pluronic F127 (PF127) on microspheres, poly[D,L-lactic-co-glycolic acid] (PLGA) microspheres were coated with Pluronic F127 gel and the in vitro release was evaluated. The results demonstrated that PF127, which gelled at 37 degrees C, inhibited the initial burst release of drug from microspheres effectively.
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Wang QY, Guo P, Duan LL, Shen ZH, Chen HL. alpha-1,3-Fucosyltransferase-VII stimulates the growth of hepatocarcinoma cells via the cyclin-dependent kinase inhibitor p27Kip1. Cell Mol Life Sci 2005; 62:171-8. [PMID: 15666088 DOI: 10.1007/s00018-004-4349-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
After the transfection of alpha-1,3-fucosyltransferase (FucT)-VII cDNA into H7721 human hepatocarcinoma cells, the protein expression of some cyclins, cyclin-dependent kinases (CDKs) and cyclin-dependent kinase inhibitors (CDIs) p16INK4 and p21waf1/Cip1 were unchanged. However, CDI p27Kip1 protein, both the total amount and the amount that bound to CDK2, but not its mRNA, was significantly reduced. The de-inhibited CDK2 stimulated the phosphorylation of retinoblastoma (Rb) protein and facilitated the G1/S transition and growth rate of the cells. The decrease of p27Kip1 protein, the increase of CDK2 activity and Rb phosphorylation, as well as the cell growth and percentage of S phase cells were correlated to the increased amount of cell surface sialyl Lewis X (SLe(x)) antigen in cells with different alpha-1,3-FucT-VII expression. The reduction in p27Kip1 and the difference in its expression among different transfected cells were blocked by the SLe(x) antibody KM93 in a dose-dependent manner, indicating that p27Kip1 expression was influenced by alpha-1,3-FucT-VII and its product SLe(x). The MEK/MAPK signaling pathway was more important than the PI-3K pathway in the regulation of p27Kip1 expression.
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Wen YR, Chang LP, Chen HL, Liu CF. Comparision of interleukin-6 and malondialdehyde levels in diabetic patients in Taiwan. DIABETES, NUTRITION & METABOLISM 2004; 17:368-70. [PMID: 15887631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The purpose of this study was to compare the levels of interleukin-6 (IL-6) and malondialdehyde (MDA) in healthy controls and diabetic patients without coronary heart disease (CHD). Fasting serum IL-6 and MDA were determined in 30 healthy controls and 52 (20 Type 1 and 32 Type 2) diabetic patients without clinical evidence of CHD. MDA was calculated as oxidative stress. The IL-6 concentration was used to evaluate the cytokine function. Results showed that the serum IL-6 and MDA concentrations are significantly higher in Type 2 diabetic patients (p<0.05). In conclusion, we demonstrated that Type 2 diabetic patients are more influenced by oxidative stress than Type 1 diabetic patients and healthy controls, because of the action of cytokine.
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Chen SH, Su AC, Chang CS, Chen HL, Ho DL, Tsao CS, Peng KY, Chen SA. Aging of poly(2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene)/toluene solutions and subsequent effects on luminescence behavior of cast films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:8909-8915. [PMID: 15379526 DOI: 10.1021/la049083d] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Morphological effects in luminescence properties of a representative semiconducting polymer, poly(2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene) (MEH-PPV), has recently attracted much attention. Previous studies indicated that short-term heat treatment of solution-cast MEH-PPV films may result in the formation of mesomorphic order that is responsible for the "red" emission around 640 nm, in contrast to the single-chromophore "yellow" emission near 590 nm from the disordered matrix. On the basis of microscopic and spectroscopic evidence for films cast from freshly prepared and aged solutions, here we show that prolonged storage of MEHyellowPPV solutions at room temperature or lower may result in retardation of the thermally induced mesophase formation in the subsequently cast films. According to small-angle neutron scattering and differential scanning calorimetric observations over aged MEH-PPV/toluene solutions, we propose that the suppressed transformation into mesomorphic order is due to further development of nanocrystalline aggregates that serve as physical cross-links among MEH-PPV chains in the solution state upon long-term storage. These solvent-induced nanocrystalline aggregates, however, do not exhibit new spectroscopic features beyond the suppression of "red" emission at 640 nm from the mesomorphic phase.
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Chen HL, Su HJ, Liao PC, Chen CH, Lee CC. Serum PCDD/F concentration distribution in residents living in the vicinity of an incinerator and its association with predicted ambient dioxin exposure. CHEMOSPHERE 2004; 54:1421-1429. [PMID: 14659944 DOI: 10.1016/j.chemosphere.2003.10.033] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The aim of this study was to evaluate the serum polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) concentration distribution in residents living in the vicinity of an incinerator and its association with annual ambient dioxin exposure predicted by an atmospheric dispersion model. A municipal waste incinerator in Northern Taiwan was chosen for this study. This incinerator had been in operation for 6 years at the time of this study. Using the incinerator site as the center, based on the simulated ambient annual average PCDD/F concentrations. Ninety-five volunteers, all live within a radius of 5 km from the incinerator for at least 5 years, who had no occupational exposure potential, were selected based on the population distribution in each district. The average serum PCDD/F concentration for these subjects living within four zones was about 14 pg I-TEQ/g lipid. The serum distribution levels of people of the four study zones, however, were not consistent with the predicted ambient levels. Results also suggest that ambient exposure might not be the most important contributor to serum concentrations when compared to other exposure sources, such as dietary intake.
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Zheng CH, Liang WQ, Yu HY, Chen HL. Evaluation of different methods to determine the loading of proteins in PLGA microspheres. DIE PHARMAZIE 2004; 59:232-3. [PMID: 15074601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Various determination methods for protein encapsulation efficiency of PLGA microspheres were compared. Acetonitrile is recommended as an extraction solvent.
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