1
|
Okumura T, Chang CH, Koga K, Shiratani M, Sato T. Influence of electric potential-induced by atmospheric pressure plasma on cell response. Sci Rep 2023; 13:15960. [PMID: 37749124 PMCID: PMC10520067 DOI: 10.1038/s41598-023-42976-4] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 09/17/2023] [Indexed: 09/27/2023] Open
Abstract
Plasma irradiation leads not only active species, but also reactive chemical species, ultraviolet light, electric fields, magnetic fields, and shock waves. To date the effects of reactive chemical species have been mainly discussed. To understand the biological effect caused by an electric potential induced with an atmospheric-pressure plasma, the behavior of cell stimulated by electric potential was investigated using HeLa cell. The cell concentration assay revealed that less than 20% of cells inactivated by potential stimulation and the remained cells proliferate afterward. Fluorescent microscopic observation revealed that potential stimulation is appreciable to transport the molecules through membrane. These results show that potential stimulation induces intracellular and extracellular molecular transport, while the stimulation has a low lethal effect. A possible mechanism for this molecular transport by potential stimulation was also shown using numerical simulation based on an equivalent circuit of the experimental system including adhered HeLa cell. The potential formation caused by plasma generation is decisive in the contribution of plasma science to molecular biology and the elucidation of the mechanism underlying a biological response induction by plasma irradiation.
Collapse
Affiliation(s)
- Takamasa Okumura
- Faculty of Information Science and Electrical Engineering, Kyushu University, Fukuoka, Fukuoka, 819-0395, Japan.
| | - Chia-Hsing Chang
- Institute of Fluid Science, Tohoku University, Sendai, Miyagi, 980-8577, Japan
| | - Kazunori Koga
- Faculty of Information Science and Electrical Engineering, Kyushu University, Fukuoka, Fukuoka, 819-0395, Japan
| | - Masaharu Shiratani
- Faculty of Information Science and Electrical Engineering, Kyushu University, Fukuoka, Fukuoka, 819-0395, Japan
| | - Takehiko Sato
- Institute of Fluid Science, Tohoku University, Sendai, Miyagi, 980-8577, Japan.
| |
Collapse
|
2
|
Chang CH, Yen KT, Li AL, Li YR, Su KW. LED-pumped eye-safe pulse laser with an extracavity optical parametric oscillator. Opt Lett 2023; 48:3877-3880. [PMID: 37527072 DOI: 10.1364/ol.496161] [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] [Received: 05/22/2023] [Accepted: 06/21/2023] [Indexed: 08/03/2023]
Abstract
An LED-side-pumped Nd:YAG/Cr4+:YAG passively Q-switched (PQS) laser containing an extracavity optical parametric oscillator (EOPO) is demonstrated. As far as we know, it is the first LED-pumped eye-safe laser. The Nd:YAG pump module is optimized to increase the PQS pulse energy to 24 mJ at 1064 nm. By using a single-pass EOPO design, the output energy of the signal pulse at 1573 nm is 7.44 mJ with a pulse width of 16 ns, the peak power is 434 kW, and the pump-to-signal conversion efficiency is 31%. For double-pass EOPO operation, the pump-to-signal conversion efficiency increases to 45.8%, the output energy of signal pulse is up to 10.98 mJ with a pulse width of 23.5 ns, and the peak power is 459 kW.
Collapse
|
3
|
Ak M, Gumus S, Aghayev A, Chang CH, Fu B, Roberts MS, Woodard PK, Bae KT. The Resolution Rate of Pulmonary Embolism on CT Pulmonary Angiography: a Prospective Study. Eur J Radiol 2022; 155:110466. [PMID: 35986988 DOI: 10.1016/j.ejrad.2022.110466] [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: 04/17/2022] [Revised: 07/25/2022] [Accepted: 08/06/2022] [Indexed: 11/29/2022]
Abstract
PURPOSE To prospectively assess the rate of clot resolution from CT pulmonary angiography (CTPA) in patients with acute pulmonary embolism (PE). MATERIALS AND METHODS This prospective cohort study included 290 patients (136 men, 154 women; mean age, 51.9 years) with acute PE. All patients had a CTPA at the presentation and had at least one follow-up within 6 months (mean 72.7 days). Sixty-four percent of patients had follow-up scans for research purposes within a pre-determined period (between 28 and 184 days; mean, 78.27 days) and 36 % had (between 2 and 184 days; mean, 62.78 days) for a clinical indication. The volume of each clot was measured using a semi-automated quantification program. The resolution rate was evaluated by interval-censored analysis. RESULTS The overall estimated probability of complete resolution was 42 % at 7 days, 56 % at 10 days, and 71 % at 45 days. Achieving complete resolution was significantly faster in patients with peripheral clots (HR: 1.78; CI: 1.05-3.03, p = 0.032) but slower in patients with consolidation and history of venous thromboembolism (VTE), (HR: 0.37; CI: 0.18-0.79, p = 0.01 and HR: 0.57; CI: 0.35-0.91, p = 0.019, respectively). Although the patients with cancer showed a faster resolution rate (HR: 1.67; CI: 1.05-2.68, p = 0.032), the mortality rate was significantly higher than non-cancer patients. CONCLUSION The resolution rate of clot burden in acute PE was associated with patients' clinical presentation variables and CTPA imaging biomarkers. This information may be incorporated into designing a prediction rule and determining the appropriate duration of anticoagulation therapy in patients with acute PE.
Collapse
Affiliation(s)
- M Ak
- Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - S Gumus
- Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, PA, United States.
| | - A Aghayev
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | - C H Chang
- Department of Medicine, School of Medicine, Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, United States
| | - B Fu
- Data and Statistical Sciences, Abbvie, Inc., Lake Bluff, IL, United States
| | - M S Roberts
- Department of Medicine, School of Medicine, Department of Biomedical Informatics, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - P K Woodard
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, United States
| | - K T Bae
- Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| |
Collapse
|
4
|
Tsai YH, Yan YJ, Li YS, Chang CH, Haung CC, Chen TC, Lin SG, Ou-Yang M. Development and verification of the coaxial heterogeneous hyperspectral imaging system. Rev Sci Instrum 2022; 93:063105. [PMID: 35778029 DOI: 10.1063/5.0088474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 04/29/2022] [Indexed: 06/15/2023]
Abstract
A hyperspectral imaging system (HIS) is a helpful tool that acquires spatial and spectral information from a target. This study developed a coaxial heterogeneous HIS (CHHIS) to collect spectral images with wavelengths ranging from 400 to 1700 nm. In this system, a visible (VIS) spectrometer and a short-wave infrared (SWIR) spectrometer are combined with a coaxial optical path to share the same field of view. This structure reduces the complexity of spatial registration and maintains the scanning duration of two spectrometers as that of a single spectrometer. The spectrometers are also replaceable for extending the detecting spectral range of the system. The calibration methodologies, including spatial correction, spectral calibration, and reflectance calibration, were developed for this system. The signal-to-noise ratio of VIS and SWIR spectrometers in the CHHIS was up to 40 and 60 dB when the exposure time of the VIS and SWIR imaging sensors was 1000 and 10 ms, respectively. When the target distance was at 600 mm, the spatial error of VIS and SWIR images in the scanning direction was less than 1 pixel; these results proved that the system was stable.
Collapse
Affiliation(s)
- Y H Tsai
- Institute of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
| | - Y J Yan
- Institute of Electrical and Control Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
| | - Y S Li
- Institute of Electrical and Control Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
| | - C H Chang
- Institute of Biomedical Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
| | - C C Haung
- Department of Tropical Fruit Trees (Fengshan Tropical Horticultural Experiment Branch), Taiwan Agricultural Research Institute, Kaohsiung 30010, Taiwan
| | - T C Chen
- Department of Aerospace and Systems Engineering, Feng Chia University, Taichung 30010, Taiwan
| | - S G Lin
- Department of Communication, Navigation and Control Engineering, National Taiwan Ocean University, Keelung, Taiwan
| | - M Ou-Yang
- Institute of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
| |
Collapse
|
5
|
Chen YT, Liu WS, Su KY, Hsu YH, Chang CH. Acute heart failure with dilated cardiomyopathy as the first manifestation of eosinophilic granulomatosis with polyangiitis. J Eur Acad Dermatol Venereol 2021; 36:e125-e128. [PMID: 34553425 DOI: 10.1111/jdv.17693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 08/26/2021] [Accepted: 09/16/2021] [Indexed: 12/01/2022]
Affiliation(s)
- Y T Chen
- Department of Dermatology, Skin Institute, Hualian Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
| | - W S Liu
- Department of Cardiovascular Medicine, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
| | - K Y Su
- Division of Allergy, Immunology and Rheumatology, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan.,School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Y H Hsu
- School of Medicine, Tzu Chi University, Hualien, Taiwan.,Department of Pathology, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
| | - C H Chang
- Department of Dermatology, Skin Institute, Hualian Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan.,Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan.,Doctoral Degree Program in Translational Medicine, Tzu Chi University and Academia Sinica, Hualien, Taiwan
| |
Collapse
|
6
|
Chang CH, Lin CS, Ho CL. Isolated intracardiac recurrence of diffuse large B-cell lymphoma successfully treated with rituximab and bendamustine chemotherapy regimen. J Postgrad Med 2020; 66:176-177. [PMID: 32675458 PMCID: PMC7542051 DOI: 10.4103/jpgm.jpgm_683_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 03/02/2020] [Accepted: 04/23/2020] [Indexed: 11/15/2022] Open
Affiliation(s)
- CH Chang
- Division of Cardiology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - CS Lin
- Division of Cardiology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - CL Ho
- Division of Hematology and Oncology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan. E-mail:
| |
Collapse
|
7
|
Lin JW, Chang CH, Caffrey JL. Examining the association between oral health status and dementia: A nationwide nested case-controlled study. Exp Biol Med (Maywood) 2020; 245:231-244. [PMID: 32039633 DOI: 10.1177/1535370220904924] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Alzheimer’s disease as a consequence of chronic brain inflammation mediated by infectious microbes including the oral microbiome continues to attract support. Taiwan’s National Insurance database was used to evaluate associations between dental health and Alzheimer’s disease; 209,112 new cases of Alzheimer’s disease were matched 1:4 with 836,448 dementia-free controls to test the hypothesis that better dental health would be associated with less occurrence of dementia. Ten year dental records and conditional logistic regression models were used to estimate the odds ratios associated with Alzheimer’s disease. Subgroup analyses compared vascular Alzheimer’s disease and sporadic Alzheimer’s disease. As the population aged, Alzheimer’s disease diagnoses were more frequent with a 10 fold upward inflection after 60. Nearly 56% of sporadic Alzheimer’s disease patients were women but less than 50% had vascular Alzheimer’s disease. Comorbidities were 10–20% higher in the Alzheimer’s disease patients than in controls, but stroke, chronic infection, and pneumonia were 40–45% more common in the vascular Alzheimer’s disease patients. Heart disease, hypertension, diabetes, stroke, peripheral artery disease, pneumonia, and herpetic disease (HSV) were all associated with higher odds of Alzheimer’s disease. HSV was not a factor in the vascular Alzheimer’s disease. Routine dental procedures tended to lower odds ratios. Root canals and extractions that restore oral homeostasis were associated with lower odds of dementia. However, when extractions exceeded four, the odds of Alzheimer’s disease rose. The fact that Alzheimer’s disease was not associated with periodontal procedures per se but with more frequent periodontal emergencies suggested again a chronic issue. Dental health costs suggest that good dental care was associated with lower odds of Alzheimer’s disease except for radiographic costs which were consistently associated with higher odds, independent of oral health. Common comorbid conditions were associated with higher odds of Alzheimer’s disease and oral health care was associated with lower odds, providing support for the hypothesis that the oral microbiome is a factor in the development of Alzheimer’s disease. Impact statement This study clearly demonstrates the power and value of a nationally applied digital medical record. Longitudinal studies of gradually developing pathologies like dementia have often been limited by sample size and narrow and incomplete medical histories. The Taiwan National Insurance database provides an unparalleled opportunity for detailed analyses of associations between current medical conditions and a spectrum of prior medical and dental events. The temporal impact of the database will only become more important as the past historical record progressively expands going forward. The inclusion of dental records in assessing the relationship with subsequent dementia is very important because this information is often unavailable or dependent on subject recall. This study clearly establishes associations between a variety of suspected cardiovascular and metabolic factors and the odds of dementia. A critical outcome should include the design of targeted interventions and the subsequent assessment of their efficacy.
Collapse
Affiliation(s)
- J W Lin
- Cardiovascular Center, National Taiwan University Hospital Yunlin Branch, Douliu City, Yunlin County 64051
| | - C H Chang
- Department of Internal Medicine, National Taiwan University Hospital, Taipei 10617
| | - J L Caffrey
- Physiology and Cardiovascular Research Institute, University of North Texas Health Science Center, TX 76107, USA
| |
Collapse
|
8
|
Chang CH, Yano KI, Sato T. Nanosecond pulsed current under plasma-producing conditions induces morphological alterations and stress fiber formation in human fibrosarcoma HT-1080 cells. Arch Biochem Biophys 2020; 681:108252. [PMID: 31911153 DOI: 10.1016/j.abb.2020.108252] [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] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 12/26/2019] [Accepted: 01/01/2020] [Indexed: 11/24/2022]
Abstract
Cold atmospheric plasma (CAP) is a promising means for various biomedical applications, including cancer therapy. Although the biological action of CAP is considered to be brought about by synergistic effects of reactive species and electrical factors of CAP, limited information is currently available on the contribution of electrical factors to CAP-induced cell responses. We have previously demonstrated that nanosecond pulsed current (nsPC) under CAP-producing conditions significantly promoted the motility of human HT-1080 cells. In this study, we explored the effects of nsPC on cell morphology associated with cell motility. We observed that nsPC stimulation caused extended cell shape, membrane protrusion formation, and increased cell surface area, but not cell death induction. nsPC stimulation also caused elevated intracellular ROS and Ca2+. HT-1080 cells can undergo two modes of cell motility, namely mesenchymal and ameboid motility, and we found that morphological features of mesenchymal motility was partly shared with nsPC-stimulated cells. Furthermore, nsPC-stimulated cells had extended stress fibers composed of filamentous actin. Taken together, this study provides a novel insight into the electrical aspect of CAP action, and we speculate that nsPC activates a certain mechanism involving intracellular signaling for stress fiber formation, leading to altered cell morphology and increased cell motility.
Collapse
Affiliation(s)
- Chia-Hsing Chang
- Department of Mechanical System Engineering, Tohoku University, Japan
| | - Ken-Ichi Yano
- Institute of Pulsed Power Science, Kumamoto University, Japan
| | - Takehiko Sato
- Institute of Fluid Science, Tohoku University, Japan.
| |
Collapse
|
9
|
Akiyama TE, Skelhorne-Gross GE, Lightbody ED, Rubino RE, Shi JY, McNamara LA, Sharma N, Zycband EI, Gonzalez FJ, Liu H, Woods JW, Chang CH, Berger JP, Nicol CJB. Endothelial Cell-Targeted Deletion of PPAR γ Blocks Rosiglitazone-Induced Plasma Volume Expansion and Vascular Remodeling in Adipose Tissue. J Pharmacol Exp Ther 2019; 368:514-523. [PMID: 30606762 PMCID: PMC11047031 DOI: 10.1124/jpet.118.250985] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 12/06/2018] [Indexed: 12/13/2022] Open
Abstract
Thiazolidinediones (TZDs) are peroxisome proliferator-activated receptor γ (PPARγ) agonists that represent an effective class of insulin-sensitizing agents; however, clinical use is associated with weight gain and peripheral edema. To elucidate the role of PPARγ expression in endothelial cells (ECs) in these side effects, EC-targeted PPARγ knockout (Pparg ΔEC) mice were placed on a high-fat diet to promote PPARγ agonist-induced plasma volume expansion, and then treated with the TZD rosiglitazone. Compared with Pparg-floxed wild-type control (Pparg f/f) mice, Pparg ΔEC treated with rosiglitazone are resistant to an increase in extracellular fluid, water content in epididymal and inguinal white adipose tissue, and plasma volume expansion. Interestingly, histologic assessment confirmed significant rosiglitazone-mediated capillary dilation within white adipose tissue of Pparg f/f mice, but not Pparg ΔEC mice. Analysis of ECs isolated from untreated mice in both strains suggested the involvement of changes in endothelial junction formation. Specifically, compared with cells from Pparg f/f mice, Pparg ΔEC cells had a 15-fold increase in focal adhesion kinase, critically important in EC focal adhesions, and >3-fold significant increase in vascular endothelial cadherin, the main component of focal adhesions. Together, these results indicate that rosiglitazone has direct effects on the endothelium via PPARγ activation and point toward a critical role for PPARγ in ECs during rosiglitazone-mediated plasma volume expansion.
Collapse
Affiliation(s)
- Taro E Akiyama
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - Graham E Skelhorne-Gross
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - Elizabeth D Lightbody
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - Rachel E Rubino
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - Jia Yue Shi
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - Lesley A McNamara
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - Neelam Sharma
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - Emanuel I Zycband
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - Frank J Gonzalez
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - Haiying Liu
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - John W Woods
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - C H Chang
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - Joel P Berger
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| | - Christopher J B Nicol
- Cardiometabolic Disorders Department, Merck Research Laboratories, Kenilworth, New Jersey (T.E.A., L.A.M., N.S., E.I.Z., H.L., J.W.W., C.H.C., J.P.B.); Department of Pathology and Molecular Medicine (G.E.S.-G., E.D.L., C.J.B.N.), Cancer Biology and Genetics Division, Cancer Research Institute (R.E.R., C.J.B.N.), and Department of Biomedical and Molecular Sciences (J.Y.S., C.J.B.N.), Queen's University, Kingston, Ontario, Canada; National Cancer Institute, National Institutes of Health, Bethesda, Maryland (F.J.G.); and Takeda Pharmaceuticals International, Inc., Cambridge, Massachusetts (J.P.B.)
| |
Collapse
|
10
|
Chang CH, Liu CY, Chen SJ, Tsai HC. Efficacy of light therapy on nonseasonal depression among elderly adults: a systematic review and meta-analysis [Corrigendum]. Neuropsychiatr Dis Treat 2019; 15:1427. [PMID: 31213816 PMCID: PMC6549794 DOI: 10.2147/ndt.s214219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 05/02/2019] [Indexed: 11/23/2022] Open
|
11
|
Wu VC, Chen SW, Ting PC, Chang CH, Lin MS, Hsieh MJ, Wang CY, Chang SH, Chu PH, Lin YS. P5585Selection of beta-blocker in patients with cirrhosis and acute myocardial infarction: a 13-year nationwide population-based study in Asia. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy566.p5585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- V C Wu
- Chang Gung Memorial Hospital Tapei, Department of Cardiology, Taipei, Taiwan ROC
| | - S W Chen
- Chang Gung Memorial Hospital Tapei, Department of Cardiology, Taipei, Taiwan ROC
| | - P C Ting
- Chang Gung Memorial Hospital Tapei, Department of Cardiology, Taipei, Taiwan ROC
| | - C H Chang
- Chang Gung Memorial Hospital Tapei, Department of Cardiology, Taipei, Taiwan ROC
| | - M S Lin
- Chang Gung Memorial Hospital Tapei, Department of Cardiology, Taipei, Taiwan ROC
| | - M J Hsieh
- Chang Gung Memorial Hospital Tapei, Department of Cardiology, Taipei, Taiwan ROC
| | - C Y Wang
- Chang Gung Memorial Hospital Tapei, Department of Cardiology, Taipei, Taiwan ROC
| | - S H Chang
- Chang Gung Memorial Hospital Tapei, Department of Cardiology, Taipei, Taiwan ROC
| | - P H Chu
- Chang Gung Memorial Hospital Tapei, Department of Cardiology, Taipei, Taiwan ROC
| | - Y S Lin
- Chang Gung Memorial Hospital, Department of Cardiology, Chiayi, Taiwan ROC
| |
Collapse
|
12
|
Zhang Q, Li Z, Chang CH, Lou JL, Zhao MR, Lu C. Potential human exposures to neonicotinoid insecticides: A review. Environ Pollut 2018; 236:71-81. [PMID: 29414376 DOI: 10.1016/j.envpol.2017.12.101] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 11/21/2017] [Accepted: 12/25/2017] [Indexed: 05/19/2023]
Abstract
Due to their systemic character and high efficacy to insect controls, neonicotinoid insecticides (neonics) have been widely used in global agriculture since its introduction in early 1990. Recent studies have indicated that neonics may be ubiquitous, have longer biological half-lives in the environment once applied, and therefore implicitly suggested the increasing probability for human exposure to neonics. Despite of neonics' persistent characters and widespread uses, scientific literature in regard of pathways in which human exposure could occur is relatively meager. In this review, we summarized results from peer-reviewed articles published prior to 2017 that address potential human exposures through ingestion and inhalation, as well as results from human biomonitoring studies. In addition, we proposed the use of relative potency factor approach in order to facilitate the assessment of concurrent exposure to a mixture of neonics with similar chemical structures and toxicological endpoints. We believe that the scientific information that we presented in this review will aid to future assessment of total neonic exposure and subsequently human health risk characterization.
Collapse
Affiliation(s)
- Q Zhang
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Providence, College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang, People's Republic of China; Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston MA, USA
| | - Z Li
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Providence, College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang, People's Republic of China; Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston MA, USA
| | - C H Chang
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston MA, USA
| | - J L Lou
- Institute of Occupational Diseases, Zhejiang Academy of Medical Sciences, Hangzhou, People's Republic of China
| | - M R Zhao
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Providence, College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang, People's Republic of China
| | - C Lu
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston MA, USA; College of Resources and Environment, Southwest University, Chongqing, 400715, People's Republic of China.
| |
Collapse
|
13
|
Chang CH, Lin HJ, Liao YY, Chu FY, Chen KT. Elevated Aminotransferases are Predictors of Hepatic Injury in Blunt Abdominal Trauma Patients. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791302000602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Objective Computed tomography (CT) scan is currently the most commonly used tool for evaluating solid-organ injuries in trauma management. However, liberal use of CT scanning increases the risk of excess radiation exposure and toxicity from contrast material. Animal studies and clinical research on the paediatric population indicated that liver enzymes elevations were related to hepatic injury. The present study was undertaken to determine whether elevated liver enzymes were associated with the occurrence of hepatic injury in adult patients with blunt abdominal trauma. Methods This is a cross-sectional study from August 2003 to October 2006. All adult patients with blunt injury to abdomino-pelvic organs documented by CT or surgery who were admitted to Chi-Mei Medical Centre in the captioned period were included. The study population sorted to hepatic injury (HI) and no hepatic injury (NHI) groups according to the presence or absence of hepatic injury. Variables including liver enzymes were compared between the groups. Results Totally 419 patients were included, including 150 patients in the HI group and 269 patients in the NHI group. The HI group was younger and had a lower rate of laparotomy (36.3 years old vs 41.4 years old; 26% vs 42%, respectively). The mean levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the HI group were significantly higher than levels in the NHI group (439.6 IU/L vs 104.7 IU/L; 353.5 IU/L vs 76.6 IU/L, p<0.01). We define AST >200 IU/L or ALT level >125 IU/L as abnormal according to previous studies. The diagnostic characteristics of hepatic injury were 87.3% sensitivity, 80.3% specificity, 71.2% positive predictive value, and 91.9% negative predictive value. Conclusion In adults who have experienced blunt abdominal trauma, AST >200 U/L or of ALT >125 U/L are practical predictors of hepatic injury. Screening serum aminotransferases will have a role in detecting occult hepatic injury and may reduce the hazards of excessive CT scanning. (Hong Kong j.emerg.med. 2013;20:337-342)
Collapse
Affiliation(s)
| | - HJ Lin
- Sourthern Tainan University of Technology, Department of Biotechnology, Tainan, Taiwan
| | - YY Liao
- Chi-Mei Medical Centre, Emergency Department, Liouying, Taiwan
| | - FY Chu
- Chi-Mei Medical Centre, Emergency Department, Chiali, Taiwan
| | - KT Chen
- Taipei Medical University, Department of Emergency Medicine, Taipei, Taiwan
| |
Collapse
|
14
|
Hsiao KY, Li WC, Chang CH, Lin MHC, Yang JT, Wang PC, Chen KH. An Evaluation of the ACEP Guideline for Mild Head Injuries in Taiwan. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791702400204] [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] [Indexed: 11/16/2022] Open
Abstract
Introduction Traumatic brain injury (TBI) is an important issue in the emergency department. In the United States, the American College of Emergency Physicians (ACEP) published clinical guideline to select patients with mild head injuries for head computed tomography (CT) scans in 2008. The aim of this study was to identify the possible benefits of compliance with these guidelines for mild head injury patients in Taiwan. Method This was a secondary analysis on our previous study published for association of hypertension and head injuries. In our previous study, we collected data about 1290 patients with head injuries who received brain CT scans in the emergency department from September 2012 to August 2013 for a study regarding the association between head injury and hypertension. In present study, we subjected this data to further analysis to try to validate the ACEP clinical policy for mild head injuries. Results Of these 1,290 patients, 154 were found to have brain haemorrhage on the initial brain CT scan, and 5 were in need of neurosurgical intervention. A total of 859 patients met the ACEP guideline criteria, and 117 of these had brain haemorrhages. The sensitivity and specificity of the ACEP guideline to predict brain haemorrhage were 75.97% (95% confidence interval [CI], 68.44% to 82.48%) and 34.68% (95% CI, 31.91% to 37.53%), respectively. In predicting neurosurgical intervention, the sensitivity and specificity of the guideline were 100% (95% CI, 47.82% to 100%) and 33.54% (95% CI, 30.96% to 36.2%), respectively. Conclusion Although adoption of the ACEP clinical policy may reduce the number of brain CT scans in mild head injury patients who may need neurosurgical interventions, it is not a good selection tool in Taiwan.
Collapse
Affiliation(s)
- KY Hsiao
- Chang Gung Memorial Hospital, Department of Emergency Medicine; and Chang Gung University of Science and Technology, Department of Nursing, Chiayi, Taiwan
| | - WC Li
- Chang Gung Memorial Hospital, Department of Occupation Medicine, Taipei, Taiwan
| | - CH Chang
- Chang Gung University of Science and Technology, College of Nursing &the Chronic Diseases and Health Promotion Research Center, Chiayi Campus, Chiayi, Taiwan
| | - MHC Lin
- Chang Gung Memorial Hospital, Department of Neurosurgery, Chiayi, Taiwan
| | - JT Yang
- Chang Gung Memorial Hospital, Department of Neurosurgery, Chiayi; and Chang Gung University, College of Medicine, Tao-Yuan, Taiwan
| | - PC Wang
- Chang Gung Memorial Hospital, Department of Cardiology, Chiayi, Taiwan
| | - KH Chen
- Chang Gung University, College of Medicine, Tao-Yuan; and Chang Gung Memorial Hospital, Department of Physical Medicine and Rehabilitation, Chiayi, Taiwan
| |
Collapse
|
15
|
Hsu SL, Lee PY, Chang CH, Chen CH. Immunological impression cytology of the conjunctival epithelium in patients with thyroid orbitopathy-related dry eye. Genet Mol Res 2016; 15:gmr9011. [PMID: 27706674 DOI: 10.4238/gmr.15039011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Thyroid orbitopathy (TO) is an autoimmune disease that is complicated by ocular surface disorders, leading to discomfort. Dry eye is very prevalent in patients with TO. Recent studies on the pathogenesis of dry eye have focused on the inflammatory process, and some supporting evidence has been discovered. Because TO is a disorder of autoimmune origin, we assumed that the association between TO and dry eye is related to inflammation. Inflammation of the ocular surface in TO-related dry eye has not been well studied. In this study, we assessed cellular inflammation of the ocular surface and the cytokine profiles in patients with TO-related dry eye. Conjunctival impression cytology (CIC) was assessed with an immunofluorescent assay. TO-related dry eye was diagnosed by using the Schirmer test, tear break-up time, thyroid function, and clinical signs. CIC was combined with immunological staining of interleukin-1a (IL-1a), IL-1b, and IL- 6. The immunological impression cytology (IC) grade was compared to the clinical activity score of TO. All TO patients with dry eye were positive for IL-1a, IL-1b, and IL-6. However, the normal controls were also positive for IL-1a. A trend was observed between the clinical inflammatory score and immunological IC grade. This study was the first to delineate the immunological IC of TO-related dry eye. Our study aimed to investigate the pathogenesis of dry eye in TO. Our findings suggest that the conjunctival cytokines IL-1a, IL-1b, and IL-6 may play a role. The results of this study will be useful for future studies of additional inflammatory cytokines, and the levels of these cytokines could be used as an outcome to assess the efficacy of treatment, such as anti-cytokine or immunosuppression therapy, in patients with TO-related dry eye or other ocular surface inflammatory disorders.
Collapse
Affiliation(s)
- S L Hsu
- Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - P Y Lee
- Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - C H Chang
- Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - C H Chen
- Department of Medical Imaging and Radiological Sciences, Central Taiwan University of Science and Technology, Taichung, Taiwan.,Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung, Taiwan
| |
Collapse
|
16
|
Chang HT, Liu CS, Chou CT, Hsieh CH, Chang CH, Chen WC, Liu SI, Hsu SS, Chen JS, Jiann BP, Huang JK, Jan CR. Econazole induces increases in free intracellular Ca2+ concentrations in human osteosarcoma cells. Hum Exp Toxicol 2016; 24:453-8. [PMID: 16235734 DOI: 10.1191/0960327105ht558oa] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [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: 11/05/2022]
Abstract
Econazole is an antifungal drug with different in vitro effects. However, econazole's effect on osteoblast like cells is unknown. In human MG63 osteosarcoma cells, the effect of econazole on intracellular Ca2+ concentrations ([Ca2+]i) was explored by using fura-2. At a concentration of 0.1 μM, econazole started to cause a rise in [Ca2+]i in a concentration-dependent manner. Econazole-induced [Ca2+]i rise was reduced by 74% by removal of extracellular Ca2+. The econazole-induced Ca2+ influx was mediated via a nimodipine-sensitive pathway. In Ca2+ free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca2+ ATPase, caused a [Ca2+]i rise, after which the increasing effect of econazole on [Ca2+]i was abolished. Pretreatment of cells with econazole to deplete Ca2+ stores totally prevented thapsigargin from releasing Ca2+. U73122, an inhibitor of phospholipase C, abolished histamine (an inositol 1,4,5-trisphosphate dependent Ca2+ mobilizer)-induced, but not econazoleinduced, [Ca2+]i rise. Econazole inhibited 76% of thapsigargin-induced store-operated Ca2+ entry. These findings suggest that in MG63 osteosarcoma cells, econazole increases [Ca2+]i by stimulating Ca2+ influx and Ca2+ release from the endoplasmic reticulum via a phospholipase C-independent manner. In contrast, econazole acts as a potent blocker of store-operated Ca2+ entry.
Collapse
Affiliation(s)
- H T Chang
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Chang CH, Hsieh CH, Huang JC, Wang C, Liao YC, Hsueh CH, Du XH, Wang ZK, Wang X. Designing a stronger interface through graded structures in amorphous/nanocrystalline ZrCu/Cu multilayered films. Nanotechnology 2016; 27:225701. [PMID: 27103429 DOI: 10.1088/0957-4484/27/22/225701] [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] [Indexed: 06/05/2023]
Abstract
Many multilayered nano-structures appear to fail due to brittle matter along the interfaces. In order to toughen them, in this study, the microstructure and interface strength of multilayered thin films consisting of amorphous ZrCu and nanocrystalline Cu (with sharp or graded interfaces) are examined and analyzed. The interface possesses a gradient nature in terms of composition, nanocrystalline phase size and volume fraction. The bending results extracted from the nano-scaled cantilever bending samples demonstrate that multilayered films with graded interfaces would have a much higher interface bending strength/strain/modulus, and an overall improvement upgrade of more than 50%. The simple graded interface design of multilayered thin films with improved mechanical properties can offer much more promising performance in structural and functional applications for MEMS or optical coating.
Collapse
Affiliation(s)
- C H Chang
- Department of Materials and Optoelectronic Science, National Sun Yat-Sen University, Kaohsiung, Taiwan 804, Republic of China
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Lin WT, Chang CH, Cheng CY, Chen MC, Wen YR, Lin CT, Lin CW. Effects of low amplitude pulsed radiofrequency stimulation with different waveform in rats for neuropathic pain. Annu Int Conf IEEE Eng Med Biol Soc 2015; 2013:3590-3. [PMID: 24110506 DOI: 10.1109/embc.2013.6610319] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Pulsed-radiofrequency (PRF) electrical stimulation has been widely used for chronic pain treatment. It has been demonstrated with advantages of low temperature over traditional continuous radiofrequency (CRF) lesions with higher amplitude and mono polar electrode to treat pain in clinics (frequency 500 KHz, Pulse duration 20 msec, Amplitude 45 V, Treatment 2 min). We compare the effects of different pulse waveforms and PRF parameters (Pulse duration 25 ms, Treatment duration 5 min, low amplitude of 2.5/1.25 V) with a miniature bi-polar electrode on Dorsal root ganglion (DRG). The pain relief effect due to PRF is evaluated by using Von Frey method for the pain threshold index based on behavior response to mechanical stimulus of various strengths. Experimental results of Von Frey Score show that the sinusoidal group has higher responses than the square wave one. Both fast and secondary expressed proteins of c-fos and pp38 are measured from spinal cord tissue sectioning slides to characterize the pain associated inflammatory responses and their responses due to PRF stimulation.
Collapse
|
19
|
Chang CH, Chen CH, Tsao CW, Hsueh WJ. Superradiant modes in resonant quasi-periodic double-period quantum wells. Opt Express 2015; 23:11946-11951. [PMID: 25969284 DOI: 10.1364/oe.23.011946] [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
This paper firstly proposes the existence of superradiant modes in resonant quasi-periodic double-period quantum wells (QWs), which has not been observed from analyzing the structure factor by traditional methods. Using the gap map method, the reflection spectra under the relevant conditions show that there are dips in the middle and the linewidth grows linearly, despite the dips, as the number of QWs increases, which is a direct demonstration of superradiance. It is also found that the relevant conditions are divided into three regions, each of which has a different width of bandgaps.
Collapse
|
20
|
Chang CH, Cheng YH, Hsueh WJ. Twin extra-high photoluminescence in resonant double-period quantum wells. Opt Lett 2014; 39:6581-6584. [PMID: 25490626 DOI: 10.1364/ol.39.006581] [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
Twin extra high photoluminescence (PL) in resonant quasi-periodic double-period quantum wells (DPQWs) for higher-generation orders is demonstrated. In the DPQW, the number of maxima in the maximum values of the PL intensity is two, which is different from other quasi-periodic quantum wells (QWs) and traditional periodic QWs. The maximum PL intensity in a DPQW is also stronger than that in a periodic QW under the anti-Bragg condition and that in a Fibonacci QW. Although the peaks of the squared electric field for the twin PL are both located near the QWs, their field profiles are distinct.
Collapse
|
21
|
Puza N, Papich MG, Reinero C, Chang CH, Yu DH, Sharp C, DeClue A. Pharmacokinetics and preliminary safety data of a single oral dose of bosentan, a dual endothelin receptor antagonist, in cats. J Vet Pharmacol Ther 2014; 37:192-5. [PMID: 24745065 DOI: 10.1111/jvp.12083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The objective of this study was to evaluate the pharmacokinetic properties and adverse effect profile of single-dose oral bosentan, a dual endothelin receptor antagonist, in healthy cats. Pharmacokinetic parameters were determined following a single mean ± SD oral dose of 3.2 ± 0.6 mg/kg of bosentan in 6 adult cats. Blood was collected for quantification of bosentan via high-performance liquid chromatography with ultraviolet detection. Blood and urine were evaluated for CBC, plasma biochemical profile, and urinalysis, and repeat physical examinations were performed to evaluate for adverse effects. The mean terminal half-life of bosentan was 20.4 ± 17.2 h. The mean peak plasma concentration was 0.49 ± 0.24 g/mL, and the mean time to maximum plasma concentration was 6.8 ± 8.6 h. The area under the curve was 5.14 ± 3.81 h·μg/mL. Oral bosentan tablets were absorbed in cats, and no clinically important adverse events were noted. Further evaluation of repeat dosing, investigation into the in vivo efficacy of decreasing endothelin-1 concentrations in cats, as well as safety in conjunction with other medications is warranted.
Collapse
|
22
|
Hsueh WJ, Chang CH, Lin CT. Exciton photoluminescence in resonant quasi-periodic Thue-Morse quantum wells. Opt Lett 2014; 39:489-492. [PMID: 24487847 DOI: 10.1364/ol.39.000489] [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: 06/03/2023]
Abstract
This Letter investigates exciton photoluminescence (PL) in resonant quasi-periodic Thue-Morse quantum wells (QWs). The results show that the PL properties of quasi-periodic Thue-Morse QWs are quite different from those of resonant Fibonacci QWs. The maximum and minimum PL intensities occur under the anti-Bragg and Bragg conditions, respectively. The maxima of the PL intensity gradually decline when the filling factor increases from 0.25 to 0.5. Accordingly, the squared electric field at the QWs decreases as the Thue-Morse QW deviates from the anti-Bragg condition.
Collapse
|
23
|
Peng PC, Wang HY, Chang CH, Hu HL, Yang WY, Wu FK. DSBCS modulation scheme for hybrid wireless and cable television system. Opt Express 2014; 22:1135-1142. [PMID: 24515073 DOI: 10.1364/oe.22.001135] [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: 06/03/2023]
Abstract
This work develops and demonstrates a double sideband with optical carrier suppression (DSBCS) modulation scheme for a hybrid wireless and cable television system based on a phase modulator (PM) and a polarization beam splitter (PBS). A carrier suppression ratio greater than 20 dB is achieved between two sidebands. In addition, the values of carrier-to-noise ratio, composite second-order and composite triple beat in various channels after 25 km of transmission are higher than the threshold value, and the power penalty of microwave signal in back-to-back and 25 km transmission perform well. Additionally, the constellation diagram of upstream signal is successfully recovered. Above results demonstrate that the proposed scheme is highly promising for practical applications.
Collapse
|
24
|
Tsao CW, Hsueh WJ, Chang CH, Cheng YH. Quasi-Bragg conditions in Thue-Morse dielectric multilayers. Opt Lett 2013; 38:4562-4565. [PMID: 24322074 DOI: 10.1364/ol.38.004562] [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: 06/03/2023]
Abstract
The existence of quasi-Bragg conditions (QBCs) in Thue-Morse dielectric multilayers (TMDMs), based on high reflectance and large forbidden gap regions in its transmission spectra, is presented. In contrast to a single traditional Bragg condition (TBC) in periodic bilayers, there are three QBCs in TMDMs. The formula for each of these QBCs is derived. The results show that one of these QBCs just overlaps the TBC. However, a singular point with perfect transmission exists in this QBC at the quarter-wave stack, at which high reflection exists in the periodic bilayers.
Collapse
|
25
|
Chang CH, Chen CH, Hsueh WJ. Strong photoluminescence emission from resonant Fibonacci quantum wells. Opt Express 2013; 21:14656-14661. [PMID: 23787654 DOI: 10.1364/oe.21.014656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Strong photoluminescence (PL) emission from a resonant Fibonacci quantum well (FQW) is demonstrated. The maximum PL intensity in the FQW is significantly stronger than that in a periodic QW under the Bragg or anti-Bragg conditions. Moreover, the peaks of the squared electric field in the FQW are located very near each of the QWs. The optimal PL spectrum in the FQW has an asymmetrical form rather than the symmetrical one in the periodic case. The maximum PL intensity and the corresponding thickness filling factor in the FQW become greater with increasing generation order.
Collapse
Affiliation(s)
- C H Chang
- Department of Engineering Science, National Taiwan University, 1, Sec. 4, Roosevelt Road, Taipei, 10660, Taiwan
| | | | | |
Collapse
|
26
|
Liu DG, Chao CH, Chang CH, Juang JM, Liu CY, Chang SH, Chang CF, Chou CK, Tseng CC, Chiang CH, Jean YC, Tang MT, Chung SC, Chang SL. Microbeam MAD Beamline for Challenging Protein Crystallography in TPS. ACTA ACUST UNITED AC 2013. [DOI: 10.1088/1742-6596/425/1/012004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
27
|
Abstract
BACKGROUND Dental erosion is an increasingly prevalent problem in Australia, with the consumption of sports beverages suggested as a risk factor. The aim of this study was to compare the erosive potential of Australian sports beverages. METHODS Ten beverages were selected and analysed to determine their pH, titratable acidity and apparent degree of saturation with respect to apatite. The erosive potential of the beverages was measured by human enamel surface loss and surface softening following a 30-minute exposure. A taste testing panel was established to determine the palatability of the sports beverages. RESULTS All sports beverages except Sukkie and Endura produced substantial surface loss and surface softening. Compared with the other sports beverages, Sukkie and Endura had a higher pH, lower titratable acidity and higher calcium content. However, Sukkie and Endura were deemed to be less palatable than the other more acidic sports beverages. CONCLUSIONS The majority of the sports beverages tested produced dental erosion in this in vitro model. However, two new products Sukkie and Endura have lower erosive potential but also lower palatability.
Collapse
Affiliation(s)
- N J Cochrane
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Victoria, Australia
| | | | | | | | | | | | | |
Collapse
|
28
|
|
29
|
Hsu WL, Tsai MH, Lin MW, Chiu YC, Lu JH, Chang CH, Yu HS, Yoshioka T. Differential effects of arsenic on calcium signaling in primary keratinocytes and malignant (HSC-1) cells. Cell Calcium 2012; 52:161-9. [PMID: 22695135 DOI: 10.1016/j.ceca.2012.05.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 05/09/2012] [Accepted: 05/10/2012] [Indexed: 01/04/2023]
Abstract
Arsenic is highly toxic to living cells, especially skin, and skin cancer is induced by drinking water containing arsenic. The molecular mechanisms of arsenic-induced cancer, however, are not well understood. To examine the initial processes in the development of arsenic-induced cancer, we analyzed calcium signaling at an early stage of arsenic treatment of human primary cells and compared the effects with those observed with arsenic treatment in carcinoma-derived cells. We found that arsenic inhibited inositol trisphosphate receptor (IP3R) function in the endoplasmic reticulum by inducing phosphorylation, which led to decreased intracellular calcium levels. Blockade of IP3R phosphorylation by the serine/threonine protein kinase Akt inhibitor wortmannin rescued calcium signaling. In contrast, arsenic treatment of cells derived from a carcinoma (human squamous carcinoma; HSC-1) for 1h had no obvious effect. Taken together, these results suggest that arsenic-induced reduction in calcium signaling is one of the initial mechanisms underlying the malignant transformation in the development of skin cancer.
Collapse
Affiliation(s)
- W L Hsu
- Graduate Institute of Medicine, School of Medicine, Kaohsiung Medical University, Taiwan
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Song JW, Kwak YL, Lee JW, Chang CH, Kim HS, Shim YH. The optimal effect site concentration of remifentanil in combination with intravenous midazolam and topical lidocaine for awake fibreoptic nasotracheal intubation in patients undergoing cervical spine surgery. Minerva Anestesiol 2012; 78:521-526. [PMID: 22240620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
BACKGROUND Remifentanil has been suggested as a suitable agent for conscious sedation during fibreoptic intubation. We evaluated the optimal effect site concentration (Ce) of remifentanil target-controlled infusion (TCI) for awake nasotracheal fibreoptic intubation in patients undergoing elective cervical spine surgery. METHODS Nineteen ASA I-II patients were enrolled. Patients were premedicated with midazolam (<70 kg 1.5 mg; >70 kg 2.0 mg) intravenously. The EC(50) and EC(95) of remifentanil Ce for smooth intubation were determined using Dixon's up-and-down method and isotonic regression. Smooth intubation was considered to have failed when patients exhibited sustained and repetitive coughing with head lift during the procedure. Intubation time, number of attempts, adverse events, and hemodynamic variables were also recorded. Patients were asked to recall the procedure and grade satisfaction at postoperative 24 h. RESULTS The EC(50) of remifentanil Ce for smooth intubation was 2.33±0.38 ng·mL-1 as calculated by Dixon's method. The estimated EC(95) of remifentanil Ce was 3.38 (95% confidence interval 2.90-3.46) ng·mL-1. Median intubation time (min) was longer in failed smooth intubation than in smooth intubation (8.0 vs. 6.1, P=0.048). Eleven patients (58%) recalled the procedure and 16 patients (84%) rated their satisfaction score as good or excellent. CONCLUSION The estimated EC(95) of remifentanil Ce for smooth nasotracheal fibreoptic intubation with conscious sedation was 3.38 (95% CI 2.90-3.46) ng·mL-1 when used in combination with midazolam and topical lidocaine. Remifentanil TCI may provide a tolerable experience of awake fibreoptic intubation despite the high incidence of recall.
Collapse
Affiliation(s)
- J W Song
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | | | | | | | | | | |
Collapse
|
31
|
Hung CY, Hu HC, Chang CH, Huang CC, Kao KC. Outcomes of early delivery in pregnant patients with acute respiratory distress syndrome. Crit Care 2012. [PMCID: PMC3363530 DOI: 10.1186/cc10719] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
32
|
Chang Chien SW, Chang CH, Chen SH, Wang MC, Madhava Rao M, Satya Veni S. Effect of sunlight irradiation on photocatalytic pyrene degradation in contaminated soils by micro-nano size TiO2. Sci Total Environ 2011; 409:4101-4108. [PMID: 21762957 DOI: 10.1016/j.scitotenv.2011.06.050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Revised: 06/12/2011] [Accepted: 06/22/2011] [Indexed: 05/31/2023]
Abstract
The enhanced catalytic pyrene degradation in quartz sand and alluvial and red soils by micro-nano size TiO(2) in the presence and absence of sunlight was investigated. The results showed that the synergistic effect of sunlight irradiation and TiO(2) was more efficient on pyrene degradation in quartz sand and red and alluvial soils than the corresponding reaction system without sunlight irradiation. In the presence of sunlight irradiation, the photooxidation (without TiO(2)) of pyrene was very pronounced in alluvial and red soils and especially in quartz sand. However, in the absence of sunlight irradiation, the catalytic pyrene degradation by TiO(2) and the photooxidation (without TiO(2)) of pyrene were almost nil. This implicates that ultra-violet (UV) wavelength range of sunlight plays an important role in TiO(2)-enhanced photocatalytic pyrene degradation and in photooxidation (without TiO(2)) of pyrene. The percentages of photocatalytic pyrene degradation by TiO(2) in quartz sand, alluvial and red soils under sunlight irradiation were 78.3, 23.4, and 31.8%, respectively, at 5h reaction period with a 5% (w/w) dose of the amended catalyst. The sequence of TiO(2)-enhanced catalytic pyrene degradation in quartz sand and alluvial and red soils was quartz sand>red soil>alluvial soil, due to different texture and total organic carbon (TOC) contents of the quartz sand and other two soils. The differential Fourier transform infrared (FT-IR) spectra of degraded pyrene in alluvial soil corroborate that TiO(2)-enhanced photocatalytic degradation rate of degraded pyrene was much greater than photooxidation (without TiO(2)) rate of degraded pyrene. Based on the data obtained, the importance for the application of TiO(2)-enhanced photocatalytic pyrene degradation and associated organic contaminants in contaminated soils was elucidated.
Collapse
Affiliation(s)
- S W Chang Chien
- Department of Environmental Engineering and Management, Chaoyang University of Technology, Wufong District, Taichung City 41349, Taiwan, ROC
| | | | | | | | | | | |
Collapse
|
33
|
Chang Chien SW, Chang CH, Chen SH, Wang MC, Madhava Rao M, Satya Veni S. Oxidative degradation of pyrene in contaminated soils by δ-MnO2 with or without sunlight irradiation. Sci Total Environ 2011; 409:4078-86. [PMID: 21752426 DOI: 10.1016/j.scitotenv.2011.06.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 06/01/2011] [Accepted: 06/07/2011] [Indexed: 05/21/2023]
Abstract
The enhanced oxidative degradation of pyrene in quartz sand and alluvial and red soils by micro-nano size birnessite (δ-MnO(2)) in the presence and absence of sunlight was investigated. The degradation of pyrene by δ-MnO(2) in quartz sand showed very little synergistic effect of sunlight irradiation on δ-MnO(2) oxidizing power. However, pyrene degradation by δ-MnO(2) in alluvial and red soils was greater under solar irradiation than the combination of photooxidation of pyrene and oxidation of pyrene by δ-MnO(2). The oxidative degradation percentages of pyrene by δ-MnO(2) under sunlight irradiation are 94.8, 97.7, and 100% for alluvial soil, red soil, and quartz sand, respectively. Oxidative degradation percentages of pyrene by δ-MnO(2) in alluvial and red soils with irradiation of sunlight almost attained a maximum at 1 h with a 5% (w/w) dose of the amended oxidant. Due to their different total organic carbon (TOC) contents, the sequence of enhanced oxidative degradation of pyrene by δ-MnO(2) in quartz sand and alluvial and red soils was quartz sand>red soil>alluvial soil. Further, this study revealed that δ-MnO(2)-enhanced oxidative degradation of pyrene is very pronounced in contaminated soils in situ even at deep soil layers where irradiation by sunlight is very limited.
Collapse
Affiliation(s)
- S W Chang Chien
- Chaoyang University of Technology, Wufong Township, Taichung County 41349, Taiwan, ROC
| | | | | | | | | | | |
Collapse
|
34
|
Kim SH, Choi EM, Chang CH, Kim HK, Chung MH, Choi YR. Comparison of the effect-site concentrations of remifentanil for Streamlined Liner of the Pharynx Airway (SLIPA) versus laryngeal mask airway SoftSealTM insertion during target-controlled infusion of propofol. Anaesth Intensive Care 2011; 39:611-7. [PMID: 21823378 DOI: 10.1177/0310057x1103900412] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This study was designed to determine the optimal dose of remifentanil required for the successful insertion of Streamlined Liner of the Pharynx Airway (SLIPA) and to compare it to that required for laryngeal mask airway (LMA) insertion in patients receiving a propofol infusion at a standard effect-site concentration. Fifty-eight patients scheduled to undergo general anaesthesia were randomly assigned to either the SLIPA (n = 29) or LMA (n = 29) group. All patients were premedicated with midazolam 0.05 mg x kg(-1) and glycopyrrolate 0.004 mg x kg(-1) intramuscularly. After the administration of lignocaine 1 mg x kg(-1) intravenously, a propofol infusion was started at an effect-site concentration of 3.5 microg x ml(-1) with a remifentanil infusion without a neuromuscular blocking agent. The remifentanil dose was determined by the modified up-and-down method starting in each group at 4 ng x ml(-1). Six minutes after induction, the airway device was inserted. Airway device insertion was classified as 'success' or 'failure' based on patient response. From the isotonic regression analysis and bootstrap distribution, the EC50 of remifentanil for SLIPA and LMA were 0.93 ng x ml(-1) (95% confidence interval [CI] 0.81 to 1.50 ng x ml(-1) and 1.36 ng x ml(-1) (95% CI 1.19 to 2.06 ng x ml(-1)) respectively, and the EC95 for SLIPA and LMA insertions were 1.90 ng x ml(-1) (95% CI 1.39 to 1.95) and 2.43 ng x ml(-1) (95% CI 1.80 to 2.46 ng x ml(-1)) respectively. Using the 83% CIs from the bootstrap distribution, EC50 for SLIPA was significantly less than that of LMA (0.83 to 1.23 vs 1.26 to 2.00, respectively) (P < 0.05). These findings suggest that the insertion of SLIPA needs about a 32% lower depth of anaesthesia than LMA insertion.
Collapse
Affiliation(s)
- S H Kim
- Department of Anesthesiology and Pain Medicine, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Republic of Korea
| | | | | | | | | | | |
Collapse
|
35
|
Chang DJ, Chang CH, Lee JS, Jeon HJ, Han DW. Propofol-remifentanil and the ankle clonus test in scoliosis patients. Anaesthesia 2010; 65:749-50. [PMID: 20642525 DOI: 10.1111/j.1365-2044.2010.06391.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
36
|
Wu M, Lou JK, Chang DY, Chang CH, Nie ZQ. Structure and function of a chloroplast DNA replication origin of Chlamydomonas reinhardtii. Proc Natl Acad Sci U S A 2010; 83:6761-5. [PMID: 16593755 PMCID: PMC386589 DOI: 10.1073/pnas.83.18.6761] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Chloroplast DNA replication in Chlamydomonas reinhardtii is initiated by the formation of a displacement loop (D-loop) at a specific site. One D-loop site with its flanking sequence was cloned in recombinant plasmids SC3-1 and R-13. The sequence of the chloroplast DNA insert in SC3-1, which includes the 0.42-kilobase (kb) D-loop region, as well as 0.2 kb to the 5' end and 0.43 kb to the 3' end of the D-loop region, was determined. The sequence is A+T-rich and contains four large stem-loop stuctures. An open reading frame potentially coding for a polypeptide of 136 amino acids was detected in the D-loop region. One stem-loop structure and two back-to-back prokaryotic-type promoters were mapped within the open reading frame. The 5.5-kb EcoRI fragment cloned in R-13 contains the 1.05-kb SC3-1 insert and its flanking regions. A yeast autonomously replicating (ARS) sequence and an ARC sequence, which promotes autonomous replication in Chlamydomonas, have been mapped within the flanking regions [Vallet, J.-M. & Rochaix, J.-D. (1985) Curr. Genet. 9, 321-324]. Both R-13 and SC3-1 were active as templates in a crude algal preparation that supports DNA synthesis. In this in vitro system, chloroplast DNA synthesis initiated near the D-loop site.
Collapse
Affiliation(s)
- M Wu
- Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, MD 21228
| | | | | | | | | |
Collapse
|
37
|
Abstract
We have found that extensively washed purple membrane has about 1 calcium and 3-4 magnesium ions bound per bacteriorhodopsin molecule. When these divalent cations are removed by any of a variety of means, the pigment changes its color from purple to blue (lambda(max) approximately 600 nm). This blue pigment, which can be formed at near neutral pH, is probably very similar to blue species formed when the pH of a purple membrane sample is lowered to approximately 2. When any of a wide variety of cations are added to a blue membrane preparation, the characteristic purple color of bacteriorhodopsin returns. Divalent and trivalent cations are much more efficient than monovalent cations in restoring the purple color and are effective at a ratio approaching one cation per pigment molecule. Besides shifting the absorption spectrum, removal of the divalent cations drastically alters the photochemical cycle of bacteriorhodopsin, including abolishing the unprotonated Schiff base (M-type) intermediate. Finally, lanthanum not only displaces the divalent cations normally bound to the purple membrane but also greatly reduces both the rate of decay of the M412 intermediate and proton uptake.
Collapse
Affiliation(s)
- C H Chang
- University of Illinois, Department of Physiology and Biophysics, 407 South Goodwin Avenue, 524 Burrill Hall, Urbana, IL 61801
| | | | | | | |
Collapse
|
38
|
Abstract
When cations are removed from the purple membrane of Halobacterium halobium it turns blue (lambda(max) = 603 nm); continuous irradiation with intense red light (lambda's >/= 630 nm) converts this deionized blue membrane into a pink membrane (lambda(max) approximately 491 nm). The rate and extent of the transformation from the blue to the pink membrane is facilitated by the removal of the last twenty COOH-terminal amino acids of bacteriorhodopsin. While the chromophore of the blue membrane is a 32:68 mixture of the 13-cis and all-trans isomers of retinal, the chromophore of the pink membrane is 9-cis rectinal. The quantum efficiency of the pink to blue membrane photoconversion is relatively high compared with that of the blue to pink membrane photoconversion. Proton release is observed when the pink membrane is converted to the blue form, and proton uptake occurs during the reverse transition. Unlike the blue membrane, the absorbance maximum of the pink membrane is only slightly affected by cation addition at low pH and ionic strength.
Collapse
|
39
|
Abstract
Several observations have already suggested that the carboxyl groups are involved in the association of divalent cations with bacteriorhodopsin (Chang et al., 1985). Here we show that at least part of the protons released from deionized purple membrane (;blue membrane') samples when salt is added are from carboxyl groups. We find that the apparent pK of magnesium binding to purple membrane in the presence of 0.5 mM buffer is 5.85. We suggest this is the pK of the carboxyl groups shifted from their usual pK because of the proton concentrating effect of the large negative surface potential of the purple membrane. Divalent cations may interact with negatively charged sites on the surface of purple membrane through the surface potential and/or through binding either by individual ligands or by conformation-dependent chelation. We find that divalent cations can be released from purple membrane by raising the temperature. Moreover, purple membrane binds only about half as many divalent cations after bleaching. Neither of these operations is expected to decrease the surface potential and thus these experiments suggest that some specific conformation in purple membrane is essential for the binding of a substantial fraction of the divalent cations. Divalent cations in purple membrane can be replaced by monovalent, (Na(+) and K(+)), or trivalent, (La(+++)) cations. Flash photolysis measurements show that the amplitude of the photointermediate, O, is affected by the replacement of the divalent cations by other ions, especially by La(+++). The kinetics of the M photointermediate and light-induced H(+) uptake are not affected by Na(+) and K(+), but they are drastically lengthened by La(+++) substitution, especially at alkaline pHs. We suggest that the surface charge density and thus the surface potential is controlled by divalent cation binding. Removal of the cations (to make deionized blue membrane) or replacement of them (e.g. La(+++)-purple membrane) changes the surface potential and hence the proton concentration near the membrane surface. An increase in local proton concentration could cause the protonation of critical carboxyl groups, for example the counter-ion to the protonated Schiff's base, causing the red shift associated with the formation of both deionized and acid blue membrane. Similar explanations based on regulation of the surface proton concentration can explain many other effects associated with the association of different cations with bacteriorhodopsin.
Collapse
|
40
|
Chang CH, Shau WY, Jiang YD, Li HY, Chang TJ, Sheu WHH, Kwok CF, Ho LT, Chuang LM. Type 2 diabetes prevalence and incidence among adults in Taiwan during 1999-2004: a national health insurance data set study. Diabet Med 2010; 27:636-43. [PMID: 20546280 DOI: 10.1111/j.1464-5491.2010.03007.x] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
AIM To evaluate annual prevalence and incidence of Type 2 diabetes and to examine possible trends among adults in Taiwan. METHODS A retrospective nationwide longitudinal study using the Taiwan National Health Insurance Research Database collected during 1999-2004. Adult patients aged > or = 20 years old with prevalent and incident Type 2 diabetes were identified using ICD-9-CM diagnostic codes. Age-specific and age-direct-standardized annual incidence and prevalence were calculated to describe their trends in different gender and age group and compared using Poisson regression. RESULTS During the study years, the age-standardized prevalence of Type 2 diabetes increased from 4.7 to 6.5% for men and from 5.3 to 6.6% for women. The increasing trends in prevalence were significant and higher among people aged < 40 and > or = 80 years. The age-standardized incidence rates of Type 2 diabetes per 1000 person-years were approximately 7.6 and remain stable for men, but decreasing from 7.7 to 6.9 for women. However, the incidence increased significantly in younger adults aged < 40 years whose relative incidence (RI with 95% confidence interval) was 1.31 (1.20-1.42) for men and 1.04 (1.01-1.08) for women. The incidence trends for people aged > or = 40 years were decreased for men and women. The differences in incidence trends between age groups and between genders were all statistically significant (all P < 0.001). CONCLUSIONS This study demonstrated a substantial increasing trend in Type 2 diabetes prevalence during 1999-2004 among adults in Taiwan. Despite the incidence decreased in older people, young men aged 20-40 years were most susceptible to higher incidence of Type 2 diabetes.
Collapse
Affiliation(s)
- C H Chang
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Abstract
Racecadotril is known as an inhibitor of enkephalinase. Increase of plasma insulin by racecadotril has been observed in rats while the mechanism of the action remains obscure. In the present study, intravenous injection of male Wistar rats with racecadotril significantly decreased blood glucose levels. However, this effect of racecadotril was not modified by naloxone at the dose sufficient to block opioid receptors. Thus, the blood glucose-lowering action of racecadotril might be through an endogenous opioid independent mechanism. Otherwise, we found that C-peptide content was also raised by racecadotril in parallel with the increase of insulin in Wistar rats. Thus, the blood glucose-lowering action of racecadotril was related to insulin secretion, but not through the inhibition of plasma insulin degradation. In addition, racecadotril showed no direct effect on insulin secretion in isolated islets or cultured HIT-T15 beta cells. The increase of plasma insulin and blood glucose-lowering action induced by racecadotril were reduced by pretreatment with atropine and enhanced by physotigmine. Direct inhibition of cholinesterase was not observed in brain homogenates treated with racecadotril. Moreover, actions of racecadotril were significantly reduced in rats receiving hemicholinium-3 at a sufficient dose to decrease endogenous acetylcholine. Activation of cholinergic tone is possibly involved in the blood glucose-lowering effect of racecadotril. Our results suggested that racecadotril increased insulin secretion to lower blood glucose mainly via regulation of parasympathetic tone in Wistar rats.
Collapse
Affiliation(s)
- H T Wu
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan City, Taiwan
| | | | | | | | | | | |
Collapse
|
42
|
Abstract
Acinetobacter has been found to be the major species responsible for mediating biological phosphate removal. The growth kinetics and phosphate uptake were investigated for an isolated Acinetobacter strain growing in a defined medium. The phosphate uptake is dependent on growth rate, temperature, and pH. Polyphosphate granules occurred in a balanced growth stage. The maximum phosphorus content in cells was 4.8% at the dilution rate of 12 day(-1). The specific phosphate uptake rate was found to be a quadratic polynomial function of the dilution rate. Increased calcium (up to 36 mg/L) and magnesium (up to 15 mg/L), and the addition of yeast extract (100 mg/L), primary effluent (20%), and fluoride (10 mg/L) did not affect phosphate uptake. Anaerobic conditioning (N(2) stripping), low pH (CO(2) stripping), and addition of sodium acetate under anaerobic conditions failed to stimulate immediate phosphate release. Nevertheless, After 21-24 h, the phosphate release was ca. 3, 5, and 15 mg P/g cell, respectively, for N(2) purging, the addition of acetate, and CO(2) purging. For two-stage completely stirred reactor operation, there was negligible phosphate overplus at the second reactor when phosphate was added, when the first reactor was subjected to phosphate limitation. When both phosphate and carbon limited the growth in the first reactor, there was slight phosphate accumulation under endogenous respiration conditions in the second reactor.
Collapse
Affiliation(s)
- O J Hao
- Department of Civil Engineering, University of Maryland, College Park Maryland 20742, USA
| | | |
Collapse
|
43
|
Chiu CH, Yu P, Chang CH, Yang CS, Hsu MH, Kuo HC, Tsai MA. Oblique electron-beam evaporation of distinctive indium-tin-oxide nanorods for enhanced light extraction from InGaN/GaN light emitting diodes. Opt Express 2009; 17:21250-21256. [PMID: 19997364 DOI: 10.1364/oe.17.021250] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This paper presents a novel and mass-producible technique to fabricate indium-tin-oxide (ITO) nanorods which serve as an omnidirectional transparent conductive layer (TCL) for InGaN/GaN light emitting diodes (LEDs). The characteristic nanorods, prepared by oblique electron-beam evaporation in a nitrogen ambient, demonstrate high optical transmittance (T>90%) for the wavelength range of 450nm to 900nm. The light output power of a packaged InGaN/GaN LED with the incorporated nanorod layer is increased by 35.1% at an injection current of 350mA, compared to that of a conventional LED. Calculations based on a finite difference time domain (FDTD) method suggest that the extraction enhancement factor can be further improved by increasing the thickness of the nanorod layer, indicating great potential to enhance the luminous intensity of solid-state lighting devices using ITO nanorod structures.
Collapse
Affiliation(s)
- C H Chiu
- Department of Photonics and Institute of Electro-Optical Engineering, National Chiao-Tung University, Hsinchu, Taiwan, R.O.C
| | | | | | | | | | | | | |
Collapse
|
44
|
Park WK, Chang CH, Chae JE, Kim MH, Cho YL, Ahn DS. Phosphodiesterase inhibition by naloxone augments the inotropic actions of beta-adrenergic stimulation. Acta Anaesthesiol Scand 2009; 53:1043-51. [PMID: 19572940 DOI: 10.1111/j.1399-6576.2009.02023.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [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: 11/28/2022]
Abstract
BACKGROUND In a shock state, naloxone generates the cardiovascular pressor effect by displacing the endogenous opiate-like peptide beta-endorphin, resulting in restoration of the normal response to catecholamines. In addition to this opioid antagonistic effect, the non-opiate receptor-mediated effect has also been proposed. The aim of this study was to define the mechanism of non-opiate receptor-mediated action of naloxone. METHODS In guinea-pig ventricular tissues, cumulative concentration-response curves for isoproterenol as well as for forskolin and 3-isobutylmethylxanthine (IBMX) were obtained by increasing the concentration stepwise. To assess the effect on the phosphodiesterase (PDE), the effects of naloxone on contractile forces induced by isoproterenol (0.05 microM) in the presence of IBMX, cilostamide (a PDE III inhibitor), or rolipram (a PDE IV inhibitor) were observed. Naloxone-induced changes in cAMP production by isoproterenol both in the absence and in the presence of IBMX were measured. Naloxone-induced changes in cAMP production by forskolin in the presence of IBMX were also measured. RESULTS Naloxone (30 microM) produced a leftward shift of the isoproterenol concentration-response curve (0.01-2 microM) without changing the maximal response. Forskolin (0.5-10 microM) produced a concentration-dependent increase in contractile forces. Naloxone increased the maximal inotropic response of forskolin. Naloxone showed no effect on the IBMX concentration-response curve. In the presence of IBMX (200 microM), naloxone did not alter the contractions evoked by isoproterenol or forskolin. Whereas naloxone increased contractile forces significantly (approximately 25%) more than that of isoproterenol in the presence of rolipram, no alteration of contractile forces in the cilostamide-incubated muscles was observed. Naloxone caused a concentration-related increase of cAMP in the absence of IBMX, but caused no change in its presence. CONCLUSIONS The enhancement of myocardial contractility by naloxone in the presence of stimulation of adenylyl cyclase activity appears to be mediated by inhibition of PDE, specifically PDE III.
Collapse
Affiliation(s)
- W K Park
- Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Korea.
| | | | | | | | | | | |
Collapse
|
45
|
Liao JY, Hu CC, Chen CC, Chang CH, Deng TC. Full-length sequence analysis of a distinct isolate of Bidens mottle virus infecting sunflower in Taiwan. Arch Virol 2009; 154:723-5. [PMID: 19308314 DOI: 10.1007/s00705-009-0356-2] [Citation(s) in RCA: 4] [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] [Received: 11/24/2008] [Accepted: 03/02/2009] [Indexed: 11/27/2022]
Abstract
The full-length genome of a potyvirus, previously known as sunflower chlorotic spot virus isolate SF-1 (SCSV-SF-1) which causes novel symptoms on sunflowers (Helianthus annuus), was sequenced and analyzed. The genome of SCSV-SF-1 is 9,741 nucleotides long, encoding a polyprotein of 3,071 amino acids containing the consensus motifs of potyviruses. Sequence comparison revealed that the 3'-terminus of SCSV-SF-1 shared over 96% similarities with isolates of Bidens mottle virus (BiMoV). However, SCSV-SF-1 has a very narrow host range, excluding the diagnostic host species for BiMoV, Bidens pilosa and Zinnia elegans. Therefore, SCSV-SF-1 is a distinct isolate of BiMoV. This is the first report of the full-length nucleotide sequence of BiMoV infecting sunflower in Taiwan.
Collapse
Affiliation(s)
- J Y Liao
- Agricultural Research Institute, Council of Agriculture, Wufeng, Taichung, Taiwan, ROC
| | | | | | | | | |
Collapse
|
46
|
Chang CH, Chang SR, Lin JS, Lee YT, Yeh SR, Chen H. A CMOS neuroelectronic interface based on two-dimensional transistor arrays with monolithically-integrated circuitry. Biosens Bioelectron 2009; 24:1757-64. [PMID: 18951013 DOI: 10.1016/j.bios.2008.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2008] [Revised: 09/03/2008] [Accepted: 09/04/2008] [Indexed: 11/17/2022]
Abstract
The ability to monitor and to elicit neural activity with a high spatiotemporal resolution has grown essential for studying the functionality of neuronal networks. Although a variety of microelectrode arrays (MEAs) has been proposed, very few MEAs are integrated with signal-processing circuitry. As a result, the maximum number of electrodes is limited by routing complexity, and the signal-to-noise ratio is degraded by parasitics and noise interference. This paper presents a single-chip neuroelectronic interface integrating oxide-semiconductor field-effect transistors (OSFETs) with signal-processing circuitry. After the chip was fabricated with the standard complementary-metal-oxide-semiconductor (CMOS) process, polygates of specific transistors were etched at die-level to form OSFETs, while metal layers were retained to connect the OSFETs into two-dimensional arrays. The complete removal of polygates was confirmed by high-resolution image scanners, and the reliability of OSFETs was examined by measuring their electrical characteristics. Through a gate oxide of only 7nm thick, each OSFET can record and stimulate neural activity extracellularly by capacitive coupling. The capability of the full chip in neural recording and stimulation was further experimented using the well-characterised escape circuit of the crayfish. Experimental results indicate that the OSFET-based neuroelectronic interface can be used to study neuronal networks as faithfully as conventional electrophysiological tools. Moreover, the proposed simple, die-level fabrication process of the OSFETs underpins the development of various field-effect biosensors on a large scale with on-chip circuitry.
Collapse
Affiliation(s)
- C H Chang
- Institute of Electronics Engineering, National Tsing Hua University, HsinChu, Taiwan
| | | | | | | | | | | |
Collapse
|
47
|
Wang JL, Lin KL, Chen WC, Chou CT, Huang CJ, Liu CS, Hsieh CH, Chang CH, Huang JK, Chang HT, Liu SI, Hsu SS, Jan CR. Effect of Celecoxib on Ca2+Fluxes and Proliferation in MDCK Renal Tubular Cells. J Recept Signal Transduct Res 2008; 25:237-49. [PMID: 16393914 DOI: 10.1080/10799890500464704] [Citation(s) in RCA: 10] [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: 10/25/2022]
Abstract
The effect of celecoxib on renal tubular cells is largely unexplored. In Madin Darby canine kidney (MDCK) cells, the effect of celecoxib on intracellular CaCa2+ concentration ([Ca2+]i) and proliferation was examined by using the Ca(2 +)-sensitive fluorescent dye fura-2 and the viability detecting fluorescent dye tetrazolium, respectively. Celecoxib (> or =1 micro M) caused an increase of [CaCa2+]i in a concentration-dependent manner. Celecoxib-induced [CaCa2+]i increase was partly reduced by removal of extracellular CaCa2+. Celecoxib-induced CaCa2+ influx was independently suggested by MnCa2+ influx-induced fura-2 fluorescence quench. In Ca(2 +)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2 +)-ATPase, caused a monophasic [CaCa2+]i increase, after which celecoxib only induced a tiny [CaCa2+]i increase; conversely, pretreatment with celecoxib completely inhibited thapsigargin-induced [CaCa2+]i increases. U73122, an inhibitor of phospholipase C, abolished ATP (but not celecoxib)-induced [CaCa2+]i increases. Overnight incubation with 1 or 10 micro M celecoxib decreased cell viability by 80% and 100%, respectively. These data indicate that celecoxib evokes a [CaCa2+]i increase in renal tubular cells by stimulating both extracellular CaCa2+ influx and intracellular CaCa2+ release and is highly toxic to renal tubular cells in vitro.
Collapse
Affiliation(s)
- J L Wang
- Department of Rehabilitation, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Tsai BN, Chang CH, Lee DJ. Fractionation of soluble microbial products (SMP) and soluble extracellular polymeric substances (EPS) from wastewater sludge. Environ Technol 2008; 29:1127-1138. [PMID: 18942580 DOI: 10.1080/09593330802217740] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Dissolved organic matter (DOM) in soluble microbial products (SMP), loosely bound (LBEPS) and tightly bound extracellular polymeric substances (TBEPS) were extracted from wastewater sludge, fractionated by size exclusion chromatography and characterized by ultraviolet absorbance at 230, 254 and 280 nm, the dissolved organic carbon (DOC) content and excitation-emission-matrix (EEM) spectra. The DOM of molecular weight (MW) > 20000 Da accounted for 33% of SMP, including proteins of high aromaticity, and 22% of both LBEPS and TBEPS, which were composed of organic acid-like substances and proteins, respectively. Polyaluminum chloride (PACI) coagulation effectively removed this DOM fraction. Conversely, the DOM of MW < 1000 Da were mostly non-aromatic organic acids (and possibly polysaccharides) of low aromaticity for SMP and both EPS, and removal by PAC1 coagulation was minimal. The findings indicated that the chemical characteristics of DOM in SMP and LBEPS were similar but not identical. The TBEPS and LBEPS exhibited significantly different DOM based on DOC distribution or EEM fingerprint.
Collapse
Affiliation(s)
- B N Tsai
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | | | | |
Collapse
|
49
|
Chang CH, Ramshaw JD. Dynamical evolution of volume fractions in multipressure multiphase flow models. Phys Rev E Stat Nonlin Soft Matter Phys 2008; 77:066305. [PMID: 18643369 DOI: 10.1103/physreve.77.066305] [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: 01/09/2008] [Indexed: 05/26/2023]
Abstract
Compared to single-pressure models, multipressure multiphase flow models require additional closure relations to determine the individual pressures of the different phases. These relations are often taken to be evolution equations for the volume fractions. We present a rigorous theoretical framework for constructing such equations for compressible multiphase mixtures in terms of submodels for the relative volumetric expansion rates DeltaE_{i} of the phases. These quantities are essentially the rates at which the phases dynamically expand or contract in response to pressure differences, and represent the general tendency of the volume fractions to relax toward values that produce local pressure equilibrium. We present a simple provisional model of this type in which DeltaE_{i} is proportional to pressure differences divided by the time required for sound waves to traverse an appropriate characteristic length. It is shown that the resulting approach to pressure equilibrium is monotonic rather than oscillatory, and occurs instantaneously in the incompressible limit.
Collapse
Affiliation(s)
- C H Chang
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | | |
Collapse
|
50
|
Lin JS, Chang SR, Chang CH, Lu SC, Chen H. CMOS-micromachined, two-dimenisional transistor arrays for neural recording and stimulation. ACTA ACUST UNITED AC 2007; 2007:2365-8. [PMID: 18002468 DOI: 10.1109/iembs.2007.4352802] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In-plane microelectrode arrays have proven to be useful tools for studying the connectivities and the functions of neural tissues. However, seldom microelectrode arrays are monolithically-integrated with signal-processing circuits, without which the maximum number of electrodes is limited by the compromise with routing complexity and interferences. This paper proposes a CMOS-compatible, two-dimensional array of oxide-semiconductor field-effect transistors(OSFETs), capable of both recording and stimulating neuronal activities. The fabrication of the OSFETs not only requires simply die-level, post-CMOS micromachining process, but also retains metal layers for monolithic integration with signal-processing circuits. A CMOS microsystem containing the OSFET arrays and gain-programmable recording circuits has been fabricated and tested. The preliminary testing results are presented and discussed.
Collapse
Affiliation(s)
- J S Lin
- Inst. of Electronics Engineering, the NTHU, No. 101, Sec. 2, Kuang-Fu Rd., Hsin-Chu, Taiwan 30013
| | | | | | | | | |
Collapse
|