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Nachalon Y, Nativ-Zeltzer N, Evangelista LM, Dhar SI, Lin SJ, Shen SC, Belafsky PC. Cervical Fibrosis as a Predictor of Dysphagia. Laryngoscope 2020; 131:548-552. [PMID: 32628787 DOI: 10.1002/lary.28880] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [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: 03/25/2020] [Revised: 05/29/2020] [Accepted: 06/01/2020] [Indexed: 11/07/2022]
Abstract
OBJECTIVE Radiotherapy of head and neck cancer (HNCA) causes dysfunction through radiation-induced fibrosis (RIF). We hypothesize that the degree of cervical fibrosis is associated with swallowing dysfunction. This study evaluated the association between cervical fibrosis and swallowing dysfunction in patients after radiation therapy for HNCA. STUDY DESIGN Cross sectional study. METHODOLOGY A convenience sample of patients with dysphagia who were at least 1 year post radiation therapy for HNCA underwent simultaneous cervical ultrasound (US) and video-fluroscopic swallow study (VFSS). US determinants of fibrosis were measurements of sternocleidomastoid fascia (SCMF) thickness bilaterally at the level of the cricoid. Primary and secondary outcome variables on VFSS were pharyngeal constriction ratio, a validated measure of pharyngeal contractility, and penetration aspiration scale (PAS). A qualitative assessment of lateral neck rotation was performed as a functional measure of neck fibrosis. RESULTS Simultaneous cervical US and VFSS examinations were performed on 18 patients with a history of radiotherapy for HNCA and on eight controls. The mean (±SD) age of the entire cohort (N = 26) was 66 (±10) years. Individuals with a history of radiation had significantly thinner mean SCMF (0.26 [±0.04 mm]) compared to controls (0.48 [±0.06 mm]; P < .05). Individuals with thinner SCMF were more likely to have moderate to severe restriction in lateral neck rotation, a higher PCR, and a higher PAS (P < .05). CONCLUSION Thinner sternocleidomastoid fascia on ultrasound in patients having undergone radiotherapy for head and neck cancer was associated with reduced lateral neck movement, poorer pharyngeal constriction and greater penetration/aspiration scale. The data suggest that cervical fibrosis is associated with swallowing dysfunction in head and neck cancer survivors and support the notion that, "As the neck goes, so does the swallow." LEVEL OF EVIDENCE 3. Laryngoscope, 131:548-552, 2021.
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Affiliation(s)
- Yuval Nachalon
- Department of Otolaryngology-Head and Neck Surgery, University of California Davis, Sacramento, California, U.S.A
| | - Nogah Nativ-Zeltzer
- Department of Otolaryngology-Head and Neck Surgery, University of California Davis, Sacramento, California, U.S.A
| | - Lisa M Evangelista
- Department of Otolaryngology-Head and Neck Surgery, University of California Davis, Sacramento, California, U.S.A
| | - Shumon I Dhar
- Department of Otolaryngology-Head and Neck Surgery, University of California Davis, Sacramento, California, U.S.A
| | - Sharon J Lin
- Department of Otolaryngology-Head and Neck Surgery, University of California Davis, Sacramento, California, U.S.A
| | - Shih C Shen
- Department of Otolaryngology-Head and Neck Surgery, University of California Davis, Sacramento, California, U.S.A
| | - Peter C Belafsky
- Department of Otolaryngology-Head and Neck Surgery, University of California Davis, Sacramento, California, U.S.A
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Ian Dhar S, Wegner AM, Rodnoi P, Wuellner JC, Mehdizadeh OB, Shen SC, Nachalon Y, Nativ-Zeltzer N, Belafsky PC, Klineberg EO. Fluoroscopic Swallowing Abnormalities in Dysphagic Patients Following Anterior Cervical Spine Surgery. Ann Otol Rhinol Laryngol 2020; 129:1101-1109. [DOI: 10.1177/0003489420929046] [Citation(s) in RCA: 6] [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] [Indexed: 01/29/2023]
Abstract
Objectives: To evaluate the precise objective fluoroscopic abnormalities in persons with dysphagia following anterior cervical spine surgery (ACSS). Methods: 129 patients with dysphagia after ACSS were age and sex matched to 129 healthy controls. All individuals underwent videofluoroscopic swallow study (VFSS). VFSS parameters abstracted included upper esophageal sphincter (UES) opening, penetration aspiration scale (PAS), and pharyngeal constriction ratio (PCR). Other data collected included patient-reported outcome measures of voice and swallowing, number of levels fused, type of plate, vocal fold immobility, time from surgery to VFSS, and revision surgery status. Results: The mean age of the entire cohort was 63 (SD ± 11) years. The mean number of levels fused was 2.2 (±0.9). 11.6% (15/129) were revision surgeries. The mean time from ACSS to VFSS was 58.3 months (±63.2). The majority of patients (72.9%) had anterior cervical discectomy and fusion (ACDF). For persons with dysphagia after ACSS, 7.8% (10/129) had endoscopic evidence of vocal fold immobility. The mean UES opening was 0.84 (±0.23) cm for patients after ACSS and 0.86 (±0.22) cm for controls ( P > .0125). Mean PCR was 0.12 (±0.12) for persons after ACSS and 0.08 (±0.08) for controls, indicating significant post-surgical pharyngeal weakness ( P < .0125). The median PAS was 1 (IQR 1) for persons after ACSS as well as for controls. For ACSS patients, PCR had a weak correlation with EAT-10 ( P < .0125). Conclusion: Chronic swallowing dysfunction after ACSS appears to be secondary to pharyngeal weakness and not diminished UES opening, the presence of aspiration, vocal fold immobility, or ACSS instrumentation factors. Level of Evidence: 3b
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Affiliation(s)
- Shumon Ian Dhar
- Johns Hopkins University, Department of Otolaryngology-Head and Neck Surgery, Baltimore, MD
| | - Adam M. Wegner
- Washington University in Saint Louis, Department of Orthopedic Surgery, Saint Louis, MO, USA
| | - Pope Rodnoi
- University of California Davis, Department of Orthopaedic Surgery, Sacramento, CA, USA
| | - John C. Wuellner
- University of California Davis, Department of Orthopaedic Surgery, Sacramento, CA, USA
| | - Omid Benjamin Mehdizadeh
- University of California Davis, Department of Otolaryngology-Head and Neck Surgery, Sacramento, CA
| | - Shih C. Shen
- University of California Davis, Department of Otolaryngology-Head and Neck Surgery, Sacramento, CA
- Chang Gung Memorial Hospital Department of Otolaryngology-Head and Neck Surgery, Linkou
| | - Yuval Nachalon
- University of California Davis, Department of Otolaryngology-Head and Neck Surgery, Sacramento, CA
| | - Nogah Nativ-Zeltzer
- University of California Davis, Department of Otolaryngology-Head and Neck Surgery, Sacramento, CA
| | - Peter C. Belafsky
- University of California Davis, Department of Otolaryngology-Head and Neck Surgery, Sacramento, CA
| | - Eric O. Klineberg
- University of California Davis, Department of Orthopaedic Surgery, Sacramento, CA, USA
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Dhar SI, Wegner AM, Rodnoi P, Wuellner JC, Mehdizadeh OB, Shen SC, Nachalon Y, Nativ-Zeltzer N, Klineberg EO, Belafsky PC. Swallowing Characteristics in Zenker's-like Diverticulum After Anterior Cervical Spine Surgery. Laryngoscope 2019; 130:1383-1387. [PMID: 31461167 DOI: 10.1002/lary.28266] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [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: 03/23/2019] [Revised: 07/12/2019] [Accepted: 08/12/2019] [Indexed: 11/09/2022]
Abstract
OBJECTIVES A Zenker's diverticulum (ZD) is a hypopharyngeal pulsion diverticula caused by dysfunction of the cricopharyngeus muscle with herniation of hypopharyngeal mucosa through Killian's dehiscence. Anterior cervical spine surgery (ACSS) can cause a Zenker's-like traction diverticulum (ZTD) with a similar presentation but different pathophysiology. The purpose of this investigation was to compare the fluoroscopic parameters and surgical outcomes of ZTD after ACSS to those of typical ZD. STUDY DESIGN Case-control study. METHODS The charts of patients undergoing a videofluoroscopic swallow study after ACSS between January 1, 2014, and January 1, 2018, were evaluated for evidence of ZTD. Patients with ZTD were age and gender matched to persons with ZD. Fluoroscopic parameters and patient-reported outcomes were compared between groups. RESULTS Eleven patients with ZTD were identified. The mean pharyngeal constriction ratio (PCR) was significantly higher for persons with ZTD (0.87 [±0.07] vs. 0.17 [±0.08]; P < 0.05). Mean hyolaryngeal elevation was significantly less (2.5 [±0.9] cm vs. 3.5 [±0.7] cm) and mean diverticulum size significantly smaller (1.3 [±1.0] cm vs. 2.3 [±2.0] cm) for persons with ZTD (P < 0.05). Five ZTD patients had exposed hardware necessitating open approach for removal. CONCLUSION We report the largest cohort of ZTD after ACSS. ZTD are smaller than traditional Zenker's and associated with more pharyngeal weakness, poorer laryngeal elevation, and worse treatment outcomes. Although these diverticula can be managed endoscopically, the high percentage of exposed cervical hardware necessitates a thorough preoperative assessment and frequent need for open management and pharyngeal repair. LEVEL OF EVIDENCE 3b Laryngoscope, 130:1383-1387, 2020.
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Affiliation(s)
- Shumon I Dhar
- Center for Voice and Swallowing, Department of Otolaryngology-Head & Neck Surgery, University of California Davis, Sacramento, California
| | - Adam M Wegner
- Department of Orthopedic Surgery, Washington University in Saint Louis, Saint Louis, Missouri, U.S.A
| | - Pope Rodnoi
- Department of Orthopaedic Surgery, University of California Davis, Sacramento, California
| | - John C Wuellner
- Department of Orthopaedic Surgery, University of California Davis, Sacramento, California
| | - Omid B Mehdizadeh
- Center for Voice and Swallowing, Department of Otolaryngology-Head & Neck Surgery, University of California Davis, Sacramento, California
| | - Shih C Shen
- Center for Voice and Swallowing, Department of Otolaryngology-Head & Neck Surgery, University of California Davis, Sacramento, California
| | - Yuval Nachalon
- Center for Voice and Swallowing, Department of Otolaryngology-Head & Neck Surgery, University of California Davis, Sacramento, California
| | - Nogah Nativ-Zeltzer
- Center for Voice and Swallowing, Department of Otolaryngology-Head & Neck Surgery, University of California Davis, Sacramento, California
| | - Eric O Klineberg
- Department of Orthopaedic Surgery, University of California Davis, Sacramento, California
| | - Peter C Belafsky
- Center for Voice and Swallowing, Department of Otolaryngology-Head & Neck Surgery, University of California Davis, Sacramento, California
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Yang E, Scheff JD, Shen SC, Farnum MA, Sefton J, Lobanov VS, Agrafiotis DK. A late-binding, distributed, NoSQL warehouse for integrating patient data from clinical trials. Database (Oxford) 2019; 2019:baz032. [PMID: 30854563 PMCID: PMC6409386 DOI: 10.1093/database/baz032] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/25/2019] [Accepted: 02/16/2019] [Indexed: 12/02/2022]
Abstract
Clinical trial data are typically collected through multiple systems developed by different vendors using different technologies and data standards. That data need to be integrated, standardized and transformed for a variety of monitoring and reporting purposes. The need to process large volumes of often inconsistent data in the presence of ever-changing requirements poses a significant technical challenge. As part of a comprehensive clinical data repository, we have developed a data warehouse that integrates patient data from any source, standardizes it and makes it accessible to study teams in a timely manner to support a wide range of analytic tasks for both in-flight and completed studies. Our solution combines Apache HBase, a NoSQL column store, Apache Phoenix, a massively parallel relational query engine and a user-friendly interface to facilitate efficient loading of large volumes of data under incomplete or ambiguous specifications, utilizing an extract-load-transform design pattern that defers data mapping until query time. This approach allows us to maintain a single copy of the data and transform it dynamically into any desirable format without requiring additional storage. Changes to the mapping specifications can be easily introduced and multiple representations of the data can be made available concurrently. Further, by versioning the data and the transformations separately, we can apply historical maps to current data or current maps to historical data, which simplifies the maintenance of data cuts and facilitates interim analyses for adaptive trials. The result is a highly scalable, secure and redundant solution that combines the flexibility of a NoSQL store with the robustness of a relational query engine to support a broad range of applications, including clinical data management, medical review, risk-based monitoring, safety signal detection, post hoc analysis of completed studies and many others.
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Affiliation(s)
- Eric Yang
- Covance, the Drug Development Division of LabCorp Carnegie Center, Princeton, NJ, USA
| | - Jeremy D Scheff
- Covance, the Drug Development Division of LabCorp Carnegie Center, Princeton, NJ, USA
| | - Shih C Shen
- Covance, the Drug Development Division of LabCorp Carnegie Center, Princeton, NJ, USA
| | - Michael A Farnum
- Covance, the Drug Development Division of LabCorp Carnegie Center, Princeton, NJ, USA
| | - James Sefton
- Covance, the Drug Development Division of LabCorp Carnegie Center, Princeton, NJ, USA
| | - Victor S Lobanov
- Covance, the Drug Development Division of LabCorp Carnegie Center, Princeton, NJ, USA
| | - Dimitris K Agrafiotis
- Covance, the Drug Development Division of LabCorp Carnegie Center, Princeton, NJ, USA
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Shen SC, Li JS, Huang MC. Design a light pattern of multiple concentric circles for LED fishing lamps using Fourier series and an energy mapping method. Opt Express 2014; 22:13460-13471. [PMID: 24921540 DOI: 10.1364/oe.22.013460] [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
Fourier series and an energy mapping method were used in this study to design a lens that produces a light pattern of multiple concentric circles (LPMCC) for a light-emitting diode (LED) fishing lamp. Fourier series were used to represent the light intensity distribution curve (LIDC) of the LPMCC light pattern. Energy mapping involves performing angular energy mapping based on the LIDCs of an LED light source and LPMCC to design a freeform lens. Type I and Type II LPMCC lenses were designed according to the phototaxis behavior of fish to create a LPMCC light pattern of interleaving light-dark zones that attracts fish shoals to stay in an area for a long period. The experimental results indicated that, in comparing the LIDCs of the Type I and II lenses with the respective simulation values, the normalized cross-correlation (NCC) value reached 96%. According to a 24-hour observation of the phototaxis of Poecilia reticulata to evaluate the effectiveness of the proposed light pattern to attract fish, when a fish shoal was habituated to a light source that emitted constant illumination light, it gradually moved away from the intense light zone and hovered around the junction of the light and dark zones. In the future, the design used in this study can be applied to LED fishing lamps to replace traditional fishing lamps.
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Shen SC, Chang SJ, Yeh CY, Teng PC. Design and testing of a uniformly solar energy TIR-R concentration lenses for HCPV systems. Opt Express 2013; 21 Suppl 6:A942-A952. [PMID: 24514935 DOI: 10.1364/oe.21.00a942] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this paper, total internal reflection-refraction (TIR-R) concentration (U-TIR-R-C) lens module were designed for uniformity using the energy configuration method to eliminate hot spots on the surface of solar cell and increase conversion efficiency. The design of most current solar concentrators emphasizes the high-power concentration of solar energy, however neglects the conversion inefficiency resulting from hot spots generated by uneven distributions of solar energy concentrated on solar cells. The energy configuration method proposed in this study employs the concept of ray tracing to uniformly distribute solar energy to solar cells through a U-TIR-R-C lens module. The U-TIR-R-C lens module adopted in this study possessed a 76-mm diameter, a 41-mm thickness, concentration ratio of 1134 Suns, 82.6% optical efficiency, and 94.7% uniformity. The experiments demonstrated that the U-TIR-R-C lens module reduced the core temperature of the solar cell from 108 °C to 69 °C and the overall temperature difference from 45 °C to 10 °C, and effectively relative increased the conversion efficiency by approximately 3.8%. Therefore, the U-TIR-R-C lens module designed can effectively concentrate a large area of sunlight onto a small solar cell, and the concentrated solar energy can be evenly distributed in the solar cell to achieve uniform irradiance and effectively eliminate hot spots.
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Ren Q, Lu J, Tan HH, Wu S, Sun L, Zhou W, Xie W, Sun Z, Zhu Y, Jagadish C, Shen SC, Chen Z. Spin-resolved Purcell effect in a quantum dot microcavity system. Nano Lett 2012; 12:3455-3459. [PMID: 22698083 DOI: 10.1021/nl3008083] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We demonstrate the spin selective coupling of the exciton state with cavity mode in a single quantum dot (QD)-micropillar cavity system. By tuning an external magnetic field, each spin polarized exciton state can be selectively coupled with the cavity mode due to the Zeeman effect. A significant enhancement of spontaneous emission rate of each spin state is achieved, giving rise to a tunable circular polarization degree from -90% to 93%. A four-level rate equation model is developed, and it agrees well with our experimental data. In addition, the coupling between photon mode and each exciton spin state is also achieved by varying temperature, demonstrating the full manipulation over the spin states in the QD-cavity system. Our results pave the way for the realization of future quantum light sources and the quantum information processing applications.
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Affiliation(s)
- Qijun Ren
- State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), and Department of Physics, Fudan University, Shanghai 200433, China
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Zhou W, Chen Z, Zhang B, Yu CH, Lu W, Shen SC. Magnetic field control of the quantum chaotic dynamics of hydrogen analogs in an anisotropic crystal field. Phys Rev Lett 2010; 105:024101. [PMID: 20867709 DOI: 10.1103/physrevlett.105.024101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2010] [Indexed: 05/29/2023]
Abstract
We report magnetic field control of the quantum chaotic dynamics of hydrogen analogues in an anisotropic solid state environment. The chaoticity of the system dynamics was quantified by means of energy level statistics. We analyzed the magnetic field dependence of the statistical distribution of the impurity energy levels and found a smooth transition between the Poisson limit and the Wigner limit, i.e., transition between regular Poisson and fully chaotic Wigner dynamics. The effect of the crystal field anisotropy on the quantum chaotic dynamics, which manifests itself in characteristic transitions between regularity and chaos for different field orientations, was demonstrated.
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Affiliation(s)
- Weihang Zhou
- Surface Physics Laboratory, Department of Physics, and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China
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Dainty M, Kleinzeller A, Lawrence AS, Miall M, Needham J, Needham DM, Shen SC. STUDIES ON THE ANOMALOUS VISCOSITY AND FLOW-BIREFRINGENCE OF PROTEIN SOLUTIONS : III. CHANGES IN THESE PROPERTIES OF MYOSIN SOLUTIONS IN RELATION TO ADENOSINETRIPHOSPHATE AND MUSCULAR CONTRACTION. ACTA ACUST UNITED AC 2010; 27:355-99. [PMID: 19873391 PMCID: PMC2238015 DOI: 10.1085/jgp.27.4.355] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
1. An investigation of the physicochemical properties of myosin has been carried out. Prepared under standard conditions, the ratio of flow-birefringence to protein concentration is uniform. The effect of electrolytes, pH, and urea on the flow-birefringence and viscosity (relative and anomalous) of myosin has been examined. 2. Decrease or abolition of flow-birefringence does not necessarily imply far reaching denaturation, since such effects can be reversed by a variety of means. 3. When a myosin solution is treated with adenosinetriphosphate, its flow-birefringence is decreased (average 48 per cent), its anomalous viscosity is retained, and its relative viscosity is decreased (average 14 per cent). The full effect of adenosinetriphosphate is obtained at 0.004 M; a molarity very much less than that of other substances which decrease the flow-birefringence of myosin. 4. The changes in the physicochemical properties of myosin brought about by adenosinetriphosphate are spontaneously reversible, and are connected with the enzymatic action of the protein as adenosinetriphosphatase. 5. Effects similar to those of adenosinetriphosphate on the physicochemical properties of purified myosin have been obtained so far only with inosinetriphosphate. 6. Inorganic phosphate is split off by myosin from inosinetriphosphate as well as from adenosinetriphosphate. Inorganic triphosphate is split by 1 to 2 per cent solution of three times precipitated myosin. 7. Adenosinediphosphate and inorganic triphosphate act as competitive inhibitors with adenosinetriphosphate, blocking the fall of flow-birefringence. 8. The implications of the results, and the conception of active enzymic groups attached to proteins participating in cell structure, whether contractile or non-contractile, are discussed in relation to present views on muscle physiology and other biological problems.
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Affiliation(s)
- M Dainty
- Biochemical Laboratory, University of Cambridge
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Lawrence AS, Miall M, Needham J, Shen SC. STUDIES ON THE ANOMALOUS VISCOSITY AND FLOW-BIREFRINGENCE OF PROTEIN SOLUTIONS : II. ON DILUTE SOLUTIONS OF PROTEINS FROM EMBRYONIC AND OTHER TISSUES. ACTA ACUST UNITED AC 2010; 27:233-71. [PMID: 19873385 PMCID: PMC2238011 DOI: 10.1085/jgp.27.3.233] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. An extensive investigation has been made of protein particle shape using the methods of flow-birefringence and anomalous viscosity measurement in the coaxial cell. 2. As a result of investigations on a number of proteins, it is concluded that they may be divided into four groups. Group A consists of those which show flow-anomaly both in the bulk phase and in the surface film. These also show flow-birefringence in the bulk phase. Examples: tobacco mosaic disease virus nucleoprotein; myosin. Though corpuscular proteins, they have elongated particles before denaturation. Group B consists of those which show flow-anomaly only (in the first instance) in the surface film, and no flow-birefringence in the bulk phase. They are probably close to spherical in shape in solution, but form elongated particles as they denature in the surface film. After this process has been completed, they may show flow-anomaly also in the bulk phase. Some proteins show flow-anomaly in the surface film immediately it forms, others only show it after a certain time has elapsed for the building up of the film. We designate the former as group B1 and the latter as group B2. Group B1, immediate surface film flow-anomaly. Examples: serum euglobulin, amphibian embryo euglobulin b. Group B2, slowly appearing surface film flow-anomaly. After the film has once been fully formed and then dispersed by shaking, the solution may have the properties of that of a protein in group B1; i.e., anomalous flow in the film may occur immediately on testing in the viscosimeter. Examples: avian ovalbumin, amphibian embryo pseudoglobulin. Group C consists of those proteins which show flow-anomaly neither in the bulk phase nor in the surface film, under the conditions used by us. They are probably close to spherical in shape. Examples: insulin, methaemoglobin, amphibian embryo euglobulin c, mucoproteins. 3. The theoretical significance of protein fibre molecules, whether native or formed by denaturation in the living cell, is discussed, especially in relation to experimental morphology and cytology.
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Lawrence AS, Needham J, Shen SC. STUDIES ON THE ANOMALOUS VISCOSITY AND FLOW-BIREFRINGENCE OF PROTEIN SOLUTIONS : I. GENERAL BEHAVIOUR OF PROTEINS SUBJECTED TO SHEAR. ACTA ACUST UNITED AC 2010; 27:201-32. [PMID: 19873384 PMCID: PMC2238014 DOI: 10.1085/jgp.27.3.201] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. A coaxial viscosimeter which permits the simultaneous determination of relative and anomalous viscosity and of flow-birefringence is described. Flow-anomaly and flow-birefringence are regarded as characteristic of elongated micelles and molecules. 2. Such methods have been applied to dilute solutions of proteins. The conditions under which the coaxial (Couette) viscosimeter measures the viscosity of the bulk phase and the surface film phase respectively have been investigated and are described. 3. The general behaviour of protein solutions subjected to shear is summarised.
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Abstract
Batch-fabrication of a micro-ball lens array (MBA) could not only reduce micro assembly costs but also replace conventional ball lenses or costly GRINs (Gradient Refractive Index) without compromising performance. Compared with conventional half-spherical micro-lenses, the MBA is a spherical micro-lens that can focus light in all directions, thus providing the flexibility required for optical applications. Current MBAs are made of SU-8 photoresist by an extrusion process rather than the traditional thermal reflow process. The aim of this study was to develop a new process for MBA batch-fabrication, performed at ambient temperature, by spin-coating SU-8 onto a silicon-wafer surface, which serves as an extrusion plate, and extruding it through a nozzle to form an MBA. The nozzle consists of a nozzle orifice and nozzle cavity, the former being defined and made from SU-8 photoresist using ultra-violet (UV) lithography, which results in good mechanical properties. In this paper, the fabrication of 4 x 4 MBAs with diameters ranging from 60 to 550 um is described. Optical measurements indicated a diameter variance within 3% and a maximum coupling efficiency of approximately 62% when the single mode fiber (SMF) was placed at a distance of 10 um from the MBA. The results of this study proved that MBA fabrication by the extrusion process can enhance the coupling efficiency.
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Affiliation(s)
- S C Shen
- Department of Systems and Naval Mechatronic Engineering, National Cheng Kung University, Tainan, Taiwan 701
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Chen Z, Zhou W, Zhang B, Yu CH, Zhu J, Lu W, Shen SC. Realization of anisotropic diamagnetic kepler problem in a solid state environment. Phys Rev Lett 2009; 102:244103. [PMID: 19659011 DOI: 10.1103/physrevlett.102.244103] [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: 02/08/2009] [Indexed: 05/28/2023]
Abstract
The anisotropic diamagnetic Kepler problem (ADKP) is realized experimentally by the orbital electrons of a P donor in Si under magnetic fields. The interference of electron wave packets which leads to quasi-Landau resonances (QLR) were observed. Applying the closed-orbit theory to an anisotropic solid state environment, we have identified orbits responsible for the QLR manifesting the quantum chaotic behavior in Rydberg atoms. The excellent consistency between the measured spectra and theoretical calculation provides unambiguous evidence of quantum chaotic dynamics of electrons in the ADKP.
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Affiliation(s)
- Zhanghai Chen
- Surface Physics Laboratory, Department of Physics, Fudan University, Shanghai 200433, People's Republic of China.
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Abstract
Dried Coptidis Rizoma was extracted with boiling water. Conditioned medium was prepared by stimulating human peripheral blood mononuclear cells with Coptidis Rizoma extract (CR). The conditioned medium was then added to human leukemic U937 cells suspension for investigating the antiproliferation effect and the induction of apoptosis. Apparent DNA fragmentation and morphological changes occurred in U937 cells after incubating for 48 h to 72 h with the conditioned medium that had been prepared with 400 microg CR solids/mL. Flow cytometric analysis revealed that the percentage of apoptotic U937 cells increased in a time- and concentration-dependent manner. The upregulation of Bax expression, the downregulation of Bcl-2 and procaspase-3 expression, and the release of cytochrome c from the mitochondria in U937 cells were all observed. Reverse transcription-polymerase chain reaction detected cytokine-related mRNA expressions in human mononuclear cells incubated with CR. An increase in the concentration of CR in culturing medium downregulated granulocyte macrophage colony-stimulatory factor mRNA expression while upregulated interleuken-2 mRNA expression. All the above-mentioned evidences suggest that CR induces the apoptosis of human leukemic U937 cells via the changes in cytokine profile and protein expressions in mitochondria pathway and that CR has the potential to be used in the therapy of leukemia due to its strong apoptosis-promoting effect.
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Affiliation(s)
- C Y Ma
- Dept. of Restaurant Management, Northern Taiwan Inst. of Science and Technology, Taipei City 112, Taiwan
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Shen SC, Ng WK, Chen Q, Zeng XT, Chew MZ, Tan RBH. Solid-phase low temperature steam-assisted synthesis of thermal stable alumina nanowires. J Nanosci Nanotechnol 2007; 7:2726-33. [PMID: 17685289 DOI: 10.1166/jnn.2007.619] [Citation(s) in RCA: 4] [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] [Indexed: 05/16/2023]
Abstract
A simple steam-assisted solid phase synthesis method was developed for synthesis of boehmite nanowires in the presence of TEAOH surfactant. The boehmite nanowires had uniform diameters (12-16 nm) and length up to 1-2 microm. The morphology of the nanostructured wires was well preserved after being converted to pure gamma-Al2O3 by thermal treatment at 600 degrees C for 5 h. The nanowires of Al2O3 exhibited excellent thermal stability by retarding the phase transformation and maintaining the wires-like nanostructure after being aged up to 1300 degrees C by preventing sintering between particles at high temperatures. The surface areas of Al2O3 nanowires could be maintained as high as 68 m2/g at 1300 degrees C while the surface areas of Al2O3 micropowder shrank to 0.89 m2/g after same thermal treatment. Both in-situ XRD and 27Al NMR results indicated that the crystal structure of gamma-Al2O3 nanowires was not transformed to alpha-Al2O3 at 1300 degrees C whereas micropowder Al2O3 was fully converted to alpha-Al2O3 at 1100 degrees C.
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Affiliation(s)
- S C Shen
- Institute of Chemical and Engineering Sciences, Jurong Island, Singapore 627833, Republic of Singapore
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17
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Shen SC, Lin CW, Lee HM, Chien LL, Chen YC. Lipopolysaccharide plus 12-o-tetradecanoylphorbol 13-acetate induction of migration and invasion of glioma cells in vitro and in vivo: Differential inhibitory effects of flavonoids. Neuroscience 2006; 140:477-89. [PMID: 16580779 DOI: 10.1016/j.neuroscience.2006.02.028] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Revised: 01/10/2006] [Accepted: 02/11/2006] [Indexed: 11/19/2022]
Abstract
In an earlier study, we reported that nitric oxide is involved in lipopolysaccharide plus 12-o-tetradecanoylphorbol 13-acetate-induced malignant transformation via increases in metalloproteinase 9 enzyme activity and inducible nitric oxide synthase gene expression in rat glioma C6 cells, however the mechanism has remained undefined. Lipopolysaccharide plus 12-o-tetradecanoylphorbol 13-acetate, but not lipopolysaccharide or 12-o-tetradecanoylphorbol 13-acetate alone, induced transformation in glioma C6 cells (but not in human glioblastoma cells GBM-8401 cells) without affecting their viability. An increase in inducible nitric oxide synthase protein expression, nitric oxide production, and metalloproteinase 9 enzyme activity is identified lipopolysaccharide/12-o-tetradecanoylphorbol 13-acetate-treated C6 cells, however lipopolysaccharide/12-o-tetradecanoylphorbol 13-acetate and 12-o-tetradecanoylphorbol 13-acetate (but not lipopolysaccharide) addition shows the similar inductive pattern on metalloproteinase 9 enzyme activity without affecting inducible nitric oxide synthase protein expression and nitric oxide production in GBM-8401 cells. Treatment of C6 cells with lipopolysaccharide/12-o-tetradecanoylphorbol 13-acetate increases the expression of phosphorylated extracellular regulated protein kinases and Jun N-terminal kinases, but not p38, proteins, and an addition of the extracellular regulated protein kinases inhibitor PD98059 or Jun N-terminal kinases inhibitors SP600125, but not the p38 inhibitor SB203580, significantly blocked lipopolysaccharide/12-o-tetradecanoylphorbol 13-acetate-induced inducible nitric oxide synthase protein expression and metalloproteinase 9 enzyme activity accompanied by blocking morphological transformation in C6 cells. Among 19 structurally related flavonoids, kaempferol and wogonin exhibit significant inhibitory effects on lipopolysaccharide/12-o-tetradecanoylphorbol 13-acetate-induced morphological transformation and colony formation, and attenuation of inducible nitric oxide synthase, phosphorylated extracellular regulated protein kinases protein expression, and metalloproteinase 9 enzyme activity was observed. 2'-OH flavone at a dose of 100 microM inhibition of lipopolysaccharide/12-o-tetradecanoylphorbol 13-acetate-induced events via apoptosis induction is identified. Furthermore, lipopolysaccharide/12-o-tetradecanoylphorbol 13-acetate, but not lipopolysaccharide or 12-o-tetradecanoylphorbol 13-acetate, induces tumoral invasion and migration in vitro and in vivo, and those are blocked by kaempferol and wogonin addition. These data suggest that combination of lipopolysaccharide and 12-o-tetradecanoylphorbol 13-acetate promotes tumoral progression via activating metalloproteinase 9 enzyme activity and inducible nitric oxide synthase gene expression, which is located downstream of mitogen-activated protein kinases activation, in rat glioma cells C6. Kaempferol and wogonin exhibit effective inhibitory effects on lipopolysaccharide/12-o-tetradecanoylphorbol 13-acetate-induced events, and thus possess the potential for further development.
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Affiliation(s)
- S C Shen
- Department of Dermatology, School of Medicine, Taipei Medical University, and Department of Dermatology, Taipei Municipal Wan-Fang Hospital-Affiliated to Taipei Medical University, 111 Xinglong Road, Taipei, Taiwan
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18
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Abstract
Moderate basic sites could be created onto mesoporous Si-MCM-41 materials by postsynthesis modification with highly dispersed La2O3. The La2O3-modified MCM-41 materials (designated here as LaM) have been characterized by Fourier transform infrared spectroscopy, temperature-programmed desorption, X-ray photoelectron spectroscopy, X-ray diffraction (XRD), and N2 adsorption/desorption and have been tested as model adsorbents for CO2 adsorption. XRD and N2 adsorption results showed that all LaM materials still maintained their uniform hexagonal mesoporous structure even after postsynthesis modification with La2O3 loading up to 20 wt %. Although the surface area, pore size, and pore volume of LaM materials decreased with increasing La2O3 loading, their capacity for CO2 storage could be significantly improved when La2O3 loading was increased from 0 to 10 wt %. Unidentate and bidentate carbonates have been identified by in situ FTIR as the two types of CO2 species adsorbed on LaM surface. The LaM material also possesses good thermal stability, allowing the model adsorbent to be regenerated at high temperature and recyclable.
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Affiliation(s)
- S C Shen
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117576, Republic of Singapore
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19
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Liu XQ, Lu W, Shen SC, Tan HH, Jagadish C, Zou J. Application of selective implantation in Al0.5Ga0.5As/In0.25Ga0.75As/GaAs pseudomorphic single quantum wire structures. J Nanosci Nanotechnol 2001; 1:389-392. [PMID: 12914079 DOI: 10.1166/jnn.2001.064] [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: 05/24/2023]
Abstract
A pseudomorphic Al0.5Ga0.5As/In0.25Ga0.75As/GaAs asymmetric quantum wire (QWR) structure was grown on GaAs V-grooved substrate by low pressure metal organic vapor phase epitaxy. The formation of crescent shaped QWRs at the bottom of the V-grooves was confirmed by both transmission electron microscopy and photoluminescence (PL) spectra. The temperature dependence of PL spectra demonstrated a fast decrease of the sidewall quantum well PL intensity with increasing temperature, which originates from relaxation of carriers from well to wire region. The self-aligned dual implantation technique was successfully used to selectively disable the adjacent quantum structures. Decrease of the PL intensity of QWR at 8 K was observed after selective implantation, which resulted from a decreased number of carriers relaxed from adjacent quantum structures.
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Affiliation(s)
- X Q Liu
- National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Science, Shanghai 200083, People's Republic of China
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20
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Chen YC, Shen SC, Lee WR, Hou WC, Yang LL, Lee TJ. Inhibition of nitric oxide synthase inhibitors and lipopolysaccharide induced inducible NOS and cyclooxygenase-2 gene expressions by rutin, quercetin, and quercetin pentaacetate in RAW 264.7 macrophages. J Cell Biochem 2001; 82:537-48. [PMID: 11500931 DOI: 10.1002/jcb.1184] [Citation(s) in RCA: 171] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Several natural flavonoids have been demonstrated to perform some beneficial biological activities, however, higher-effective concentrations and poor-absorptive efficacy in body of flavonoids blocked their practical applications. In the present study, we provided evidences to demonstrate that flavonoids rutin, quercetin, and its acetylated product quercetin pentaacetate were able to be used with nitric oxide synthase (NOS) inhibitors (N-nitro-L-arginine (NLA) or N-nitro-L-arginine methyl ester (L-NAME)) in treatment of lipopolysaccharide (LPS) induced nitric oxide (NO) and prostaglandin E2 (PGE2) productions, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) gene expressions in a mouse macrophage cell line (RAW 264.7). The results showed that rutin, quercetin, and quercetin pentaacetate-inhibited LPS-induced NO production in a concentration-dependent manner without obvious cytotoxic effect on cells by MTT assay using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide as an indicator. Decrease of NO production by flavonoids was consistent with the inhibition on LPS-induced iNOS gene expression by western blotting. However, these compounds were unable to block iNOS enzyme activity by direct and indirect measurement on iNOS enzyme activity. Quercetin pentaacetate showed the obvious inhibition on LPS-induced PGE2 production and COX-2 gene expression and the inhibition was not result of suppression on COX-2 enzyme activity. Previous study demonstrated that decrease of NO production by L-arginine analogs effectively stimulated LPS-induced iNOS gene expression, and proposed that stimulatory effects on iNOS protein by NOS inhibitors might be harmful in treating sepsis. In this study, NLA or L-NAME treatment stimulated significantly on LPS-induced iNOS (but not COX-2) protein in RAW 264.7 cells which was inhibited by these three compounds. Quercetin pentaacetate, but not quercetin and rutin, showed the strong inhibitory activity on PGE2 production and COX-2 protein expression in NLA/LPS or L-NAME/LPS co-treated RAW 264.7 cells. These results indicated that combinatorial treatment of L-arginine analogs and flavonoid derivates, such as quercetin pentaacetate, effectively inhibited LPS-induced NO and PGE2 productions, at the same time, inhibited enhanced expressions of iNOS and COX-2 genes.
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Affiliation(s)
- Y C Chen
- Graduate Institute of Pharmacognosy Science, Taipei Medical University, Taipei, Taiwan.
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21
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Lee WR, Shen SC, Lai HH, Hu CH, Fang JY. Transdermal drug delivery enhanced and controlled by erbium:YAG laser: a comparative study of lipophilic and hydrophilic drugs. J Control Release 2001; 75:155-66. [PMID: 11451505 DOI: 10.1016/s0168-3659(01)00391-1] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [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: 10/17/2022]
Abstract
The influence of an erbium:YAG laser on the transdermal delivery of drugs across skin was studied in vitro. Indomethacin and nalbuphine, which have the same molecular weight, were selected as model lipophilic and hydrophilic drugs, respectively, to compare skin permeation by laser treatment. The results indicate a significant increase in the permeation of indomethacin and nalbuphine across skin pretreated with an erbium:YAG laser. The laser had a greater effect on the permeation of hydrophilic molecules which usually possess low permeability. The laser intensity and its spot size were found to play an important role in controlling transdermal delivery of drugs. Permeation of the hydrophilic drug increased following an increase of laser energy. On the other hand, a different result was observed for the lipophilic drug transported across laser-treated skin. The stratum corneum (SC) layer in skin could be partly ablated by the erbium:YAG laser. The barrier function of the SC may also be modulated by a lower intensity of the laser without affecting the viability and structure of the epidermis/dermis as determined by histological observations. However, ultrastructural alteration of the epidermis/dermis may be caused by laser treatment. Use of an erbium:YAG laser is a good method for enhancing transdermal absorption of both lipophilic and hydrophilic drugs, because it allows precise control of SC removal, and this ablation of SC can be reversible to the original normal status.
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Affiliation(s)
- W R Lee
- Department of Dermatology, Taipei Medical University Hospital, Taipei, Taiwan
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22
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Chen YC, Shen SC, Chen LG, Lee TJ, Yang LL. Wogonin, baicalin, and baicalein inhibition of inducible nitric oxide synthase and cyclooxygenase-2 gene expressions induced by nitric oxide synthase inhibitors and lipopolysaccharide. Biochem Pharmacol 2001; 61:1417-27. [PMID: 11331078 DOI: 10.1016/s0006-2952(01)00594-9] [Citation(s) in RCA: 219] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We previously reported that oroxylin A, a polyphenolic compound, was a potent inhibitor of lipopolysaccharide (LPS)-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). In the present study, three oroxylin A structurally related polyphenols isolated from the Chinese herb Huang Qui, namely baicalin, baicalein, and wogonin, were examined for their effects on LPS-induced nitric oxide (NO) production and iNOS and COX-2 gene expressions in RAW 264.7 macrophages. The results indicated that these three polyphenolic compounds inhibited LPS-induced NO production in a concentration-dependent manner without a notable cytotoxic effect on these cells. The decrease in NO production was in parallel with the inhibition by these polyphenolic compounds of LPS-induced iNOS gene expression. However, these three compounds did not directly affect iNOS enzyme activity. In addition, wogonin, but not baicalin or baicalein, inhibited LPS-induced prostaglandin E2 (PGE2) production and COX-2 gene expression without affecting COX-2 enzyme activity. Furthermore, N-nitro-L-arginine (NLA) and N-nitro-L-arginine methyl ester (L-NAME) pretreatment enhanced LPS-induced iNOS (but not COX-2) protein expression, which was inhibited by these three polyphenolic compounds. Wogonin, but not baicalin or baicalein, similarly inhibited PGE2 production and COX-2 protein expression in NLA/LPS or L-NAME/LPS-co-treated RAW 264.7 cells. These results indicated that co-treatment with NOS inhibitors and polyphenolic compounds such as wogonin effectively blocks acute production of NO and, at the same time, inhibits expression of iNOS and COX-2 genes.
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Affiliation(s)
- Y C Chen
- Graduate Institute of Pharmacognosy Science, Taipei Medical University, 250 Wu-Hsing Street, Taipei, Taiwan
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23
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Chen YC, Tsai SH, Shen SC, Lin JK, Lee WR. Alternative activation of extracellular signal-regulated protein kinases in curcumin and arsenite-induced HSP70 gene expression in human colorectal carcinoma cells. Eur J Cell Biol 2001; 80:213-21. [PMID: 11322385 DOI: 10.1078/0171-9335-00158] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [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: 01/08/2023] Open
Abstract
We have investigated the regulation mechanism of chemical stress-induced HSP70 gene expression in human colorectal carcinoma cells (COLO205 and HT29). Our data show that chemical treatments including sodium arsenite and curcumin, induced significant synthesis of HSP70 and its mRNA. The induced HSP70 gene expression appears to be increased at the transcriptional level. The increase in HSP70 gene expression by both chemicals is associated with an increase in HSF binding to HSE and induction of HSF1 di- or trimerization. Phosphorylation and activation of extracellular signal-regulated proteins (ERK1/2) were detected in sodium arsenite-treated COLO205 and HT29 cells, and the free radical scavenger N-acetyl-L-cysteine (NAC) was able to inhibit this ERK1/2 activation and HSP70 gene expression. MAPK blockade by the specific MEK1 inhibitor (PD98059) decreased the ability of sodium arsenite to increase HSP70 gene expression in a dose-dependent manner along with dephosphorylation of ERK1/2 proteins. In contrast to arsenite treatment, activation of ERK1/2 was not detected in curcumin-treated colorectal carcinoma cells, and NAC and PD98059 did not show any inhibitory effect on HSP70 gene expression induced by curcumin. Overexpression of a dominant negative mutant of mitogen-activated protein kinase kinase kinase 1 (MEKK1-DN) prevents arsenite-induced ERK1/2 phosphorylation and HSP70 protein synthesis. These results indicated that the ERK signaling pathway can participate in HSP70 gene expression induced by the prooxidant sodium arsenite, but not by the antioxidant curcumin.
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Affiliation(s)
- Y C Chen
- Graduate Institute of Pharmacognosy Science, Taipei Medical University, Taiwan.
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24
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Jee SH, Shen SC, Chiu HC, Tsai WL, Kuo ML. Overexpression of interleukin-6 in human basal cell carcinoma cell lines increases anti-apoptotic activity and tumorigenic potency. Oncogene 2001; 20:198-208. [PMID: 11313947 DOI: 10.1038/sj.onc.1204076] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2000] [Revised: 10/13/2000] [Accepted: 11/01/2000] [Indexed: 01/24/2023]
Abstract
Interleukin-6 (IL-6) is a pleiotropic cytokine that is capable of modulating the diverse functions of cells such as acute phase responses and inflammation. Excessive or insufficient production of IL-6 may contribute to certain diseases of the skin. The aim of this study was to investigate the possible role of IL-6 in the tumorigenesis of basal cell carcinoma (BCC). Initially, we transfected IL-6 expression vector, under the control of a CMV promoter, into human BCC cells and successfully obtained IL-6-overexpressing clones (BCC/IL-6-c1 and BCC/IL-6-c2) and a mixture (BCC/IL-6). DNA synthesis assay determined using (3)H-thymidine pulse incorporation revealed that IL-6-expressing BCC cells exhibited a much higher DNA synthesis rate than the neo control or parental BCC cells. We also detected a greater abundance of IL-6-expressing cell colonies formed in soft agar than in the vector control cells. Furthermore, BCC/IL-6 cells, but not vector control cells, were resistant to UV and photodynamic therapy (PDT)-induced apoptosis, as confirmed using DNA fragmentation and morphologic change analyses. Immunoblot analysis showed that Mcl-1, an anti-apoptotic protein, was specifically up-regulated IL-6 transfectants but not in the control cells. Transient transfection of IL-6 transfectants with antisense mcl-1 greatly enhanced their apoptosis frequency by UV treatment. In tumorigenesis assay, IL-6 transfected clones formed tumors in nude mice more rapidly than the control cells. These tumors appeared to be highly vascularized using pathological examination. Supportive of this finding, we found that IL-6 transfected cells expressed elevated levels of two angiogenic factors, cyclooxygenase (Cox)-2 and vascular endothelial growth factor (VEGF). These results suggest that overexpression of IL-6 enhances the tumorigenic activity of BCC cells by both suppressing apoptosis and actively promoting angiogenesis.
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Affiliation(s)
- S H Jee
- Department of Dermatology, College of Medicine, National Taiwan University, Taipei, Taiwan
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25
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Inada R, Matsuki M, Yamada K, Morishima Y, Shen SC, Kuramoto N, Yasuno H, Takahashi K, Miyachi Y, Yamanishi K. Facilitated wound healing by activation of the Transglutaminase 1 gene. Am J Pathol 2000; 157:1875-82. [PMID: 11106560 PMCID: PMC1885758 DOI: 10.1016/s0002-9440(10)64826-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Transglutaminase 1 (TGase 1) is a Ca(2+)-dependent enzyme which catalyzes epsilon-(gamma-glutamyl)lysine cross-linking of substrate proteins such as involucrin and loricrin to generate the cornified envelope at the cell periphery of the stratum corneum. We have shown that disruption of the TGase 1 gene in mice results in neonatal lethality, absence of the cornified envelope, and impaired skin barrier function. Based on the importance of TGase 1 in epidermal morphogenesis, we have now assessed its role in wound healing. In neonatal mouse skin, TGase 1 mRNA as well as keratin 6alpha was induced in the epidermis at the wound edges as early as 2 hours after injury and that expression continued in the migrating epidermis until completion of re-epithelialization. The TGase 1 enzyme co-localized on the plasma membrane of migrating keratinocytes with involucrin, but not with loricrin, which suggests the premature assembly of the cornified envelope. Similar injuries to TGase 1 knockout mouse skins grafted on athymic nude mice showed substantial delays in wound healing concomitant with sustained K6alpha mRNA induction. From these results, we suggest that activation of the TGase 1gene is essential for facilitated repair of skin injury.
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Affiliation(s)
- R Inada
- Department of Dermatology, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto, Japan
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26
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Shen SC, Zhang WB, Cui LX. [Determination of residual acetone in soybean phospholipids by headspace gas chromatography]. Se Pu 2000; 18:571-3. [PMID: 12541755] [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: 02/28/2023] Open
Abstract
Soybean phospholipids have many functions and alimentary actions. In our country, powder soybean phospholipids are generally got by extraction with acetone, followed by vacuum drying. There may be some residual acetone present in the soybean phospholipids, which is harmful to health. So, we must know residual acetone content in the soybean phospholipids. However we have not found a method to determine the residual acetone in the soybean phospholipids. In this paper, headspace GC was used to determine residual acetone in powder soybean phospholipids. The headspace bottle was glass with a volume of 15 milliliters. Certain amounts of water, ammonium sulfate, and sample were added into the bottle. The mixture was made into a brei as soon as possible. The bottle was put into a water bath at 40 degrees C for an hour. The GC column was a 2 m x 3 mm i.d. stainless steel tube packed with GDX-103 stationary phase. Temperatures of both injector and detector were kept at 120 degrees C. Column temperature was 160 degrees C. Injection volume was 1 mL. External standard method was used for quantitation. The RSD was 1.2%. The recoveries in the range of 25.0 micrograms/g-100 micrograms/g were 98.4%-104%.
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Affiliation(s)
- S C Shen
- Analysis and Testing Center, Qiqihar University, Qiqihar 161006, China
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27
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Abstract
Our work provides evidence that a sequence characteristic of FNR binding sites, when interacted with by a trans-acting factor, activates anaerobic transcription of the nifLA operon in Enterobacter cloacae. DNA gyrase activity has been found to be important for the anaerobic transcription of the nifLA promoter. Our results suggest that anaerobic regulation of the nifLA operon is mediated through the control of the promoter region-binding trans-acting factor at the transcriptional level, while DNA supercoiling functions in providing a topological requirement for the activation of transcription.
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Affiliation(s)
- B Hu
- Laboratory of Molecular Genetics, Shanghai Institute of Plant Physiology, The Chinese Academy of Sciences, China
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28
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Shen SC, Zhang XH. [Determination of inositol by chromatography]. Se Pu 2000; 18:265-6. [PMID: 12541572] [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: 02/28/2023] Open
Abstract
Inositol was acetylated to inositol hexacetate and determined by GC. The content of inositol was got. The gas chromatographic conditions were as follows: 2 m x 3 mm i.d. column packed with 10% SE-30/201 Diatoport PAW(60-80 mesh) was kept at 240 degrees C. The temperature of both injector and FID was 260 degrees C. The flowrate of N2 carrier gas was 40 mL/min. The sample was analyzed by this method with a coefficient of variation of 0.15% and a recovery of 98.2%-104.3%.
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Affiliation(s)
- S C Shen
- Analysis and Testing Center, Qiqihar University, Qiqihar 161006, China
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29
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Hiiragi T, Sasaki H, Nagafuchi A, Sabe H, Shen SC, Matsuki M, Yamanishi K, Tsukita S. Transglutaminase type 1 and its cross-linking activity are concentrated at adherens junctions in simple epithelial cells. J Biol Chem 1999; 274:34148-54. [PMID: 10567386 DOI: 10.1074/jbc.274.48.34148] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [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: 11/06/2022] Open
Abstract
Transglutaminase type 1 was identified as a tyrosine-phosphorylated protein from the isolated junctional fraction of the mouse liver. This enzyme was reported to be involved in the covalent cross-linking of proteins in keratinocytes, but its expression and activity in other cell types have not been examined. Northern blotting revealed that transglutaminase type 1 was expressed in large amounts in epithelial tissues (lung, liver, and kidney), which was also confirmed by immunoblotting with antibodies raised against mouse recombinant protein. Immunoblotting of the isolated junctional fraction revealed that transglutaminase type 1 was concentrated in the fraction not only as a 97-kDa form but also as forms of various molecular masses cross-linked to other proteins. In agreement with this finding, endogenous transglutaminase type 1 was immunofluorescently colocalized with E-cadherin in cultured simple epithelial cells. In the liver and kidney, immunoelectron microscopy revealed that transglutaminase type 1 was concentrated, albeit not exclusively, at cadherin-based adherens junctions. Furthermore, by in vitro and in vivo labeling, transglutaminase cross-linking activity was also shown to be concentrated at intercellular junctions of simple epithelial cells. These findings suggested that the formation of covalently cross-linked multimolecular complexes by transglutaminase type 1 is an important mechanism for maintenance of the structural integrity of simple epithelial cells, especially at cadherin-based adherens junctions.
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Affiliation(s)
- T Hiiragi
- Department of Cell Biology, Faculty of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
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30
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Shiah SG, Chuang SE, Chau YP, Shen SC, Kuo ML. Activation of c-Jun NH2-terminal kinase and subsequent CPP32/Yama during topoisomerase inhibitor beta-lapachone-induced apoptosis through an oxidation-dependent pathway. Cancer Res 1999; 59:391-8. [PMID: 9927052] [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: 02/10/2023]
Abstract
Beta-lapachone (beta-Lap) has been found to inhibit DNA topoisomerases (Topos) by a mechanism distinct from that of other commonly known Topo inhibitors. Here, we demonstrated a pronounced elevation of H2O2 and O2- in human leukemia HL-60 cells treated with beta-Lap. Treatment with other Topo poisons, such as camptothecin (CPT), Vbeta-16, and GL331, did not have the same effect. On the other hand, antioxidant vitamin C (Vit C) treatment effectively antagonized beta-Lap-induced apoptosis. This suggested that a reactive oxygen species (ROS)-related pathway was involved in beta-Lap-induced apoptosis program. We also found that c-Jun NH2-terminal kinase (JNK) but not p38 mitogen-activated protein kinase or extracellular signal-regulated kinase 1/2 was persistently activated in apoptosis induced by beta-Lap. Overexpression of a dominant-negative mutant mitogen-activated protein kinase kinase kinase 1 (MEKK1-DN) or treatment with JNK-specific antisense oligonucleotide or Vit C all prevented beta-Lap-induced JNK activation and the subsequent apoptosis. Only the expression of MEKK1-DN, not Vit C treatment, blocked the JNK activity induced by CPT, Vbeta-16, or GL331. These results confirm again that ROS acts as a mediator for JNK activation during beta-Lap-induced apoptosis. Furthermore, we found that beta-Lap can stimulate CPP32/Yama activity, which was, however, markedly inhibited by the MEKK1-DN expression or Vit C treatment. Again, CPT-induced CPP32/Yama activation can be abolished by MEKK1-DN but not by Vit C treatment. Taken together, these results indicate that beta-Lap but not other Topo inhibitors triggers apoptosis signaling, i.e., JNK and subsequent CPP32/Yama activation are mediated by the generation of ROS.
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Affiliation(s)
- S G Shiah
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei
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Liao CL, Lin YL, Shen SC, Shen JY, Su HL, Huang YL, Ma SH, Sun YC, Chen KP, Chen LK. Antiapoptotic but not antiviral function of human bcl-2 assists establishment of Japanese encephalitis virus persistence in cultured cells. J Virol 1998; 72:9844-54. [PMID: 9811720 PMCID: PMC110496 DOI: 10.1128/jvi.72.12.9844-9854.1998] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.9] [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: 04/20/1998] [Accepted: 09/09/1998] [Indexed: 11/20/2022] Open
Abstract
Upon infection of Japanese encephalitis virus (JEV), baby hamster kidney (BHK-21) and Chinese hamster ovary (CHO) cells were killed by a mechanism involved in apoptosis. While readily established in a variety of cell lines, JEV persistence has never been successfully instituted in BHK-21 and CHO cells. Since stable expression of human bcl-2 in BHK-21 cells has been shown to delay JEV-induced apoptosis, in this study we investigated whether JEV persistence could be established in such cells. When constitutively expressing bcl-2, but not its closest homolog, bcl-XL, following a primary lytic infection, approximately 5 to 10% of BHK-21 and CHO cells became persistently JEV infected during a long-term culture. From the persistent bulks, several independent clones were selected and expanded to form stable cell lines that continuously produced infectious virus without marked cytopathic effects (CPE). Among these stable cell lines, the truncated nonstructural protein 1 (NS1) was also detected and was indistinguishable from the NS1 truncations previously observed in JEV-persistent murine neuroblastoma N18 cells. However, the stable expression of NS1 alone, regardless of whether it was truncated or full length, failed to render the engineered cells persistently infected by JEV, implying that aberrant NS1 proteins were likely a consequence of, rather than a cause for, the viral persistence. Enforced bcl-2 expression, which did not affect virus replication and spread during the early phase of cytolytic infection, appeared to attain JEV persistence by restriction of virus-induced CPE. Our results suggest that it is the antiapoptotic, rather than the antiviral, effect of cellular bcl-2 which plays a role in the establishment of JEV persistence.
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Affiliation(s)
- C L Liao
- Department of Microbiology and Immunology, Taiwan, Republic of China.
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32
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Kuo ML, Shen SC, Yang CH, Chuang SE, Cheng AL, Huang TS. Bcl-2 prevents topoisomerase II inhibitor GL331-induced apoptosis is mediated by down-regulation of poly(ADP-ribose)polymerase activity. Oncogene 1998; 17:2225-34. [PMID: 9811453 DOI: 10.1038/sj.onc.1202133] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [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: 11/09/2022]
Abstract
Poly (ADP-ribose) polymerase (PARP), a nuclear enzyme responsible for DNA strand breaks, has been recently suggested to be crucial for apoptosis induced by a number chemotherapeutic drugs. In this study, we demonstrated that the PARP activity could be evidently elevated with a peak at 6 h when HL-60 cells were treated with a new anticancer drug GL331. Coincident with the peak of PARP activity, an apparent DNA fragmentation and apoptotic morphology were observed in cells treated with GL331. The subsequent apoptotic DNA fragmentation induced by GL331 could be completely blocked by transfecting cells with anti-sense PARP retroviral vector or by treating cells with PARP inhibitor, 3-aminobenzamide (3-AB). This blocking effect thus suggests that activation of PARP was critically involved in GL331-induced apoptosis. The fact that Bcl-2 has been found to antagonize cell death induced by a wide variety of agents, accounts for why we examined whether if Bcl-2 could antagonize GL331 effects. Interestingly, ectopic overexpression of Bcl-2 in either HL-60 or U937 cells caused in resistance towards GL331-elicited DNA fragmentation and cytotoxic effect. Additionally, Bcl-2 also attenuated the poly(ADP-ribosyl)ation of PARP itself as well as Histone H1 at the early period of drug treatment. However, Bcl-2 did not influence the extent of DNA strand breaks induced by GL331 in either control or Bcl-2-overexpressing cells. In addition, analysis of basal PARP activity in control and several Bcl-2 overexpressing clones revealed that Bcl-2 down-regulated PARP activity under the condition without DNA damages. Above findings suggest that poly(ADP-ribosyl)ation of nuclear targets is important for apoptosis induced by DNA-reactive anticancer drugs.
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Affiliation(s)
- M L Kuo
- Laboratory of Molecular & Cellular Toxicology, Institute of Toxicology, College of Medicine, National Taiwan University, Taipei
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Abstract
Curcumin, a potent antioxidant and chemopreventive agent, has recently been found to be capable of inducing apoptosis in human hepatoma and leukemia cells by way of an elusive mechanism. Here, we demonstrate that curcumin also induces apoptosis in human basal cell carcinoma cells in a dose- and time-dependent manner, as evidenced by internucleosomal DNA fragmentation and morphologic change. In our study, consistent with the occurrence of DNA fragmentation, nuclear p53 protein initially increased at 12 h and peaked at 48 h after curcumin treatment. Prior treatment of cells with cycloheximide or actinomycin D abolished the p53 increase and apoptosis induced by curcumin, suggesting that either de novo p53 protein synthesis or some proteins synthesis for stabilization of p53 is required for apoptosis. In electrophoretic mobility gel-shift assays, nuclear extracts of cells treated with curcumin displayed distinct patterns of binding between p53 and its consensus binding site. Supportive of these findings, p53 downstream targets, including p21(CIP1/WAF1) and Gadd45, could be induced to localize on the nucleus by curcumin with similar p53 kinetics. Moreover, we immunoprecipitated extracts from basal cell carcinoma cells with different anti-p53 antibodies, which are known to be specific for wild-type or mutant p53 protein. The results reveal that basal cell carcinoma cells contain exclusively wild-type p53; however, curcumin treatment did not interfere with cell cycling. Similarly, the apoptosis suppressor Bcl-2 and promoter Bax were not changed with the curcumin treatment. Finally, treatment of cells with p53 antisense oligonucleotide could effectively prevent curcumin-induced intracellular p53 protein increase and apoptosis, but sense p53 oligonucleotide could not. Thus, our data suggest that the p53-associated signaling pathway is critically involved in curcumin-mediated apoptotic cell death. This evidence also suggests that curcumin may be a potent agent for skin cancer prevention or therapy.
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Affiliation(s)
- S H Jee
- Department of Dermatology, College of Medicine, National Taiwan University, Taipei
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34
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Chen JY, Tsai HL, Chang CY, Wang JI, Shen SC, Wu JL. Isolation and characterization of tilapia (Oreochromis mossambicus) insulin-like growth factors gene and proximal promoter region. DNA Cell Biol 1998; 17:359-76. [PMID: 9570153 DOI: 10.1089/dna.1998.17.359] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
To understand the molecular mechanism which controls the transcription of the insulin-like growth factors (IGFs) gene, we have cloned and sequenced the cDNA for the proximal promoter region of the tilapia IGFs gene and have characterized its activity by chloramphenicol acetyltransferase (CAT) transient transfected expression assays. Tilapia (Oreochromis mossambicus) IGF-I cDNA (549 bp) was amplified by PCR from single-stranded cDNA of growth hormone (GH)-induced liver RNA using a pair of oligonucleotides specific for fish IGF-I as amplification primers. Tilapia IGF-I and IGF-II 5' termini were analyzed by rapid amplification of cDNA 5' ends (5'RACE). Analysis of the 5'RACE results revealed two transcription start sites in IGF-I and one transcription start site in IGF-II. Different fragments of the 5' flanking region were transfected into human lung adenocarcinoma cells. In the cell line, maximum promoter activity was located in the distal 657 basepairs of the IGF-I 5' flanking region and in the distal 450 basepairs of the IGF-II 5' flanking region. The in vivo actions of the IGFs promoter on developmental stage expression were investigated further in transgenic zebrafish in which an IGFs promoter-driven green fluorescent protein (GFP) encoding the cDNA transgene was microinjected into embryos. Morphologic and RT-PCR studies of the transgenic zebrafish indicated that IGF-I promoter-driven GFP transcripts appeared for the first time in the 1-K-cell stage and the IGF-II promoter-driven GFP transcripts appeared for the first time in the 32-cell stage. Fluorescent (GFP) distribution was apparent within 48 h in IGF-II-transgenic zebrafish embryos, especially in eye, muscle, corpuscle, floor plate, horizontal myoseptum, yolk sac extension, and yolk sac. These results indicate that the IGF-I and IGF-II promoters are active in tissue and in a development-specific manner. Our findings also indicate that the IGF-II promoter influences the growth of fish embryos earlier than does IGF-I, and IGF-II has higher levels of expression than does IGF-I. These results suggest that the IGF-II promoter plays a growth factor role in teleost embryo development.
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Affiliation(s)
- J Y Chen
- Institute of Zoology, National Taiwan University, Taipei, ROC
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35
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Shen SC, Huang TS, Jee SH, Kuo ML. Taxol-induced p34cdc2 kinase activation and apoptosis inhibited by 12-O-tetradecanoylphorbol-13-acetate in human breast MCF-7 carcinoma cells. Cell Growth Differ 1998; 9:23-9. [PMID: 9438385] [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] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The p34cdc2 kinase is a highly regulated serine-threonine kinase that, when complexed with cyclins A and B, controls cell entry into mitosis. Recently, premature activation of p34cdc2 was shown to be required for apoptosis induced by a wide variety of agents. Here, we show that Taxol induced p34cdc2 kinase activity with a peak at 6 h in human breast carcinoma MCF-7 cells. We subsequently observed that the activation of CPP32/Yama protease as well as the cleavage of its substrate poly(ADP-ribose) polymerase occurred 9 h after Taxol treatment. Olomoucine, a potent p34cdc2 inhibitor, effectively prevented Taxol-induced p34cdc2 kinase activation and subsequent apoptosis. Furthermore, the treatment of cells with cyclin B1-specific antisense oligonucleotide also blocked Taxol-induced apoptosis, suggesting that cyclin B1-associated p34cdc2 kinase plays an important role in the induction of apoptosis by Taxol. 12-O-Tetradecanoylphorbol-13-acetate (TPA), a protein kinase C activator, was found to exert strong protection against Taxol-induced cell death in MCF-7 cells. TPA inhibited Taxol-mediated activation of p34cdc2 kinase by preventing the dephosphorylation of the Tyr-15 residue on p34cdc2 without altering the levels of Cdc2 and cyclin B1. In contrast, the ability of Taxol to enhance tubulin polymerization was not inhibited by TPA. These findings suggest that modulation of protein kinase C signaling can protect against Taxol-induced cell death by inhibiting p34cdc2 kinase activation.
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Affiliation(s)
- S C Shen
- Laboratory of Molecular & Cellular Toxicology, Institute of Toxicology, College of Medicine, National Taiwan University, Taipei
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36
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Chen JY, Chang CY, Chen JC, Shen SC, Wu JL. Production of biologically active recombinant tilapia insulin-like growth factor-II polypeptides in Escherichia coli cells and characterization of the genomic structure of the coding region. DNA Cell Biol 1997; 16:883-92. [PMID: 9260931 DOI: 10.1089/dna.1997.16.883] [Citation(s) in RCA: 34] [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: 02/05/2023] Open
Abstract
Insulin-like growth factor-II (IGF-II) is a fetal growth factor in humans, but has not been clearly identified in fish up to now. For a detailed understanding of the physiological response of fish IGF-II, the first step was to clone tilapia IGF-II cDNA from the brain cDNA library, coding the region of genomic DNA, and also expressing tilapia IGF-II polypeptides from Escherichia coli. Tilapia cDNA sequences total 1,977 bp, and predicted nucleotide sequences and amino acid sequences of tilapia share 77.9% and 90.7% homology identity with rainbow trout IGF-II, respectively. The genomic structure of the tilapia prepro-IGF-II coding region is very difficult to sequence in mammals and birds. The cloned tilapia IGF-II gene coding region appears much more complex than in other vertebrates. In tilapia IGF-II, the first coding exon I encoding part of the signal peptide sequence is 25 amino acids shorter than the first coding exon of mammals and birds. The other 23 amino acids of the signal peptide, and the first amino acids of the B domain and C domain are encoded by tilapia coding exon 2. The C, A, and D domains, and the first 20 amino acids of the E peptide are encoded by tilapia coding exon 3. The other E peptides and the 3' untranslated region (UTR) region are encoded by tilapia coding exon 4. These data show that the IGF-II genes have significantly differing structures in vertebrate evolution, and there are differences of interrupting introns in the IGF-I genomic structure compared with mammals. To obtain recombinant biologically active polypeptides, tilapia IGF-II B-C-A-D domains were amplified using the polymerase chain reaction (PCR), then ligated with glutathione S-transferase (GST, pGEX-2T vector). Tilapia recombinant IGF-II protein was purified and characterized in E. coli. The fusion protein was also digested with thrombin and appeared as a recombinant IGF-II polypeptide single band with a molecular mass of 7 kD. The recombinant tilapia IGF-II protein biological function was measured by stimulation of [3H]thymidine incorporation. The assay concentration was set up from 0 to 120 nM to stimulate tilapia ovary cell line (TO-2) significantly to uptake thymidine. The results suggest that the recombinant IGF-II protein was dose dependent.
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Affiliation(s)
- J Y Chen
- Institute of Zoology, National Taiwan University, Taipei, R.O.C
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37
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Xu W, Shen SC. Infrared emittance of medium containing nonsphere-shaped particles. Appl Opt 1997; 36:1644-1649. [PMID: 18250848 DOI: 10.1364/ao.36.001644] [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: 05/25/2023]
Abstract
The scattering and absorption sections of cylinder- and sheet-shaped particles in a binder have been investigated. The IR emittance of a coating layer composed of randomly arrayed particles embedded in the binder has been calculated in terms of the size of the particles, the volume fraction occupied by the particles, and the complex refractive indices of the particle and the binder as well as the emittance of the substrate. The calculation shows that the inhomogeneous medium including sheet-shaped particles can have lower emittance than that including cylinder- or sphere-shaped particles.
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38
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Wang WP, Xu ZZ, Shen SC. [Combined color Doppler and pulsed Doppler in the diagnosis of small hepatocellular carcinomas]. Zhonghua Wai Ke Za Zhi 1994; 32:474-6. [PMID: 7882771] [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] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The combined studies by using color Doppler (CD) and pulsed Doppler (PD) technique in 56 patients with 71 solid hepatic lesions smaller than 3 cm in diameter were carried out. The detecting rates of arterial signals in small hepatocellular carcinomas (sHCC) group, hepatic cavernous hemangiomas (HCH) group and others group were 86.9%, 37% and 33% respectively. Whereas, the average value of resistance index (RI) in sHCC group was very higher than that in other groups. By using combined CD and PD space-taking lesions of the liver are tentatively diagnosed as sHCC under conditions of color flow, arterial signals, and a RI of more than 50%. The specificity (96%) and accuracy (90%) of the diagnosis superior to the conventional US (P < 0.005).
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39
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Shen SC, Harada A, Kurokawa T, Nakao A, Nonami T, Isobe K, Imoto M, Takamatsu J, Takagi H. Partial hepatectomy for hepatocellular carcinoma in a patient with hemophilia: a case report. Hepatogastroenterology 1994; 41:283-6. [PMID: 7959555] [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] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We describe successful partial hepatectomy for hepatocellular carcinoma (HCC) in a 43-year-old man with severe factor VIII deficiency (hemophilia A). Tumor size and plasma alpha-fetoprotein (AFP) decreased spontaneously prior to surgery. HCC was found in the anterior superior segment of the liver, with invasion of the diaphragm. A limited partial resection of the liver and diaphragm was performed. The administration of factor VIII during and immediately after surgery resulted in no postoperative bleeding complications. Macroscopic findings revealed hemorrhage and necrosis throughout the intrahepatic portion of the tumor. Viable HCC cells were recognized histologically in the intrahepatic tumor and infiltrating the diaphragm. In patients with hemophilia there is a tendency for HCC to hemorrhage, which may obscure the diagnosis. Appropriate administration of factor VIII permits the safe resection of HCC in hemophilia A.
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Affiliation(s)
- S C Shen
- Department of Surgery II, Nagoya University School of Medicine, Japan
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40
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Xu W, Fu Y, Willander M, Shen SC. Theory of normal-incidence absorption for the intersubband transition in n-type indirect-gap semiconductor quantum wells. Phys Rev B Condens Matter 1994; 49:13760-13766. [PMID: 10010321 DOI: 10.1103/physrevb.49.13760] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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41
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Shen SC, Zhu JB, Mu YM, Liu PL. Wave-function mixture and composition for hybridized Zeeman states of P in Si. Phys Rev B Condens Matter 1994; 49:5300-5305. [PMID: 10011481 DOI: 10.1103/physrevb.49.5300] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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42
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Mu YM, Peng JP, Liu PL, Shen SC, Zhu JB. Effects of an external magnetic field on shallow donor levels in semiconductors. Phys Rev B Condens Matter 1993; 48:10864-10869. [PMID: 10007385 DOI: 10.1103/physrevb.48.10864] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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43
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Lao PD, Guo Y, Siu GG, Shen SC. Optical-phonon behavior in Zn1-xMnxSe: Zinc-blende and wurtzite structures. Phys Rev B Condens Matter 1993; 48:11701-11704. [PMID: 10007505 DOI: 10.1103/physrevb.48.11701] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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44
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Shen SC, Nakao A, Kishimoto W, Harada A, Nonami T, Nakano M, Takagi H. The ability of polymorphonuclear leukocytes to produce active oxygen in a model of peritonitis in rats. Surg Today 1993; 23:603-8. [PMID: 8396470 DOI: 10.1007/bf00311908] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
To elucidate the mechanism of enhancing survival in peritonitis rats treated with lentinan, a fully purified beta-1,3-glucan, we measured the active oxygen-producing ability of polymorphonuclear leukocytes (PMNs). Four groups of rats (group I, fecal peritonitis control; II, rats receiving 3 mg/kg lentinan intraperitoneally at the same time as peritonitis induction; III, rats receiving 1 mg/kg gentamicin intramuscularly; and IV, rats receiving combined lentinan-gentamicin treatment) were used. The survival period was significantly longer in group IV than in the other three groups. The ability of ascitic PMNs to produce active oxygen (superoxide, H2O2, myeloperoxidase) was significantly more than that of blood PMNs in each group at 20 h after peritonitis induction. The increase in active oxygen production in ascitic PMNs was higher in group IV compared with that in the other three groups. The concentration of lentinan in the blood was high at 24 h after administering lentinan intraperitoneally to both the normal and peritonitis rats. In the in vitro study, the superoxide production in normal rat blood PMNs was significantly higher in the presence of cytokines (IL-1 beta, IL-6, TNF-alpha) without dose-dependence but was not higher for the lentinan group than in the control. This study therefore suggests that lentinan activated the peritoneal macrophage secretory activity and produced cytokines which thus enhanced the ability of PMNs to produce active oxygen, which possesses a bactericidal ability in PMNs.
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Affiliation(s)
- S C Shen
- Department of Surgery II, Nagoya University, School of Medicine, Japan
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45
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Lu W, Mu YM, Peng JP, Shen SC, Twardowski A. Anisotropy of the electronic structure of Fe2+ in CdS in a magnetic field. Phys Rev B Condens Matter 1993; 47:16247-16251. [PMID: 10006048 DOI: 10.1103/physrevb.47.16247] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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46
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Tzeng CS, Hui CF, Shen SC, Huang PC. The complete nucleotide sequence of the Crossostoma lacustre mitochondrial genome: conservation and variations among vertebrates. Nucleic Acids Res 1992; 20:4853-8. [PMID: 1408800 PMCID: PMC334242 DOI: 10.1093/nar/20.18.4853] [Citation(s) in RCA: 172] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The complete mitochondrial (mt) genome of Crossostoma lacustre, a freshwater loach from mountain stream of Taiwan, has been cloned and sequenced. This fish mt genome, consisting of 16558 base-pairs, encodes genes for 13 proteins, two rRNAs, and 22 tRNAs, in addition to a regulatory sequence for replication and transcription (D-loop), is similar to those of the other vertebrates in both the order and orientation of these genes. The protein-coding and ribosomal RNA genes are highly homologous both in size and composition, to their counterparts in mammals, birds, amphibians, and invertebrates, and using essentially the same set of codons, including both the initiation and termination signals, and the tRNAs. Differences do exist, however, in the lengths and sequences of the D-loop regions, and in space between genes, which account for the variations in total lengths of the genomes. Our observations provide evidence for the first time for the conservation of genetic information in the fish mitochondrial genome, especially among the vertebrates.
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Affiliation(s)
- C S Tzeng
- Institute of Molecular Biology, Academia Sinica, Nankang, Taipei, Republic of China
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47
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Abstract
By taking into account all kinds of radiation source for the inhomogeneous coating layer on a substrate, that is, transmitted radiation from the radiative substrate, self-radiation of the coating layer and reflection of the coating layer to incident radiation, the radiative transfer equations are built and derived. The definitions of apparent emittance and reflectance for such an inhomogeneous coating system are given. The influence of various factors, such as layer thickness, the optical constants of components in the layer, and emittance of the substrate, on radiation and reflection properties of the coating is discussed in detail.
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48
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Xue ZT, Xu ML, Shen W, Zhuang NL, Hu WM, Shen SC. Characterization of a Gy4 glycinin gene from soybean Glycine max cv. forrest. Plant Mol Biol 1992; 18:897-908. [PMID: 1316192 DOI: 10.1007/bf00019204] [Citation(s) in RCA: 5] [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] [Indexed: 12/16/2023]
Abstract
The glycinin gene family encoding the glycinin subunits in soybean plants is composed of at least five gene members. A genomic clone lambda S312 containing the Gy4 gene from a genomic library of cv. Forrest was isolated and partially characterized. The organization of this gene was found to be similar to that of a null allele from cv. Raiden, but different from the Gy4 gene from cv. Dare. The complete nucleotide sequence of this gene has been determined. It is 2599 bp long consisting of four exons and three introns. Comparing the DNA sequences between this gene and the gene from Dare and a null allele from Raiden, the difference found in the coding region was 5'-GCAGTGCAAG-3' (nt 824 to 833) in the former case versus 5'-TGGAGTTGCAATT-3' (nt 1314 to 1326) in the latter case in the exon 2 domain, resulting in three amino acid differences and one amino acid absence. Some other differences were also found in the non-coding region. The coding sequence and 5'-flanking region of the Gy4 gene, when compared with that of other legumin genes as well as group 1 glycinin subunit genes, revealed some interesting features: (1) a transposable element-like sequence was found in the hypervariable region (HVR) of the exon 3 domain, which was lacking in the legumin and the glycinin group 1 genes; (2) in the 5'-flanking region from nt -145 to -1, two high-homology sequences were found: one from nt -141 to nt -132, the other from nt -118 to nt -92 which includes the 'legumin box' and the RY repeat element.
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Affiliation(s)
- Z T Xue
- Laboratory of Molecular Genetics, Shanghai Institute of Plant Physiology, Academia Sinica, People's Republic of China
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49
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Shan W, Fang XM, Li D, Jiang S, Shen SC, Hou HQ, Feng W, Zhou JM. Photomodulated transmission spectroscopy of the intersubband transitions in strained In1-xGaxAs/GaAs multiple quantum wells under hydrostatic pressure. Phys Rev B Condens Matter 1991; 43:14615-14620. [PMID: 9997353 DOI: 10.1103/physrevb.43.14615] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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50
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Jiang S, Shen SC, Li QG, Zhu HR, Ju GL, Giriat W. Pressure dependence of the optical absorption edge of Cd1-xMnxSe. Phys Rev B Condens Matter 1989; 40:8017-8019. [PMID: 9991242 DOI: 10.1103/physrevb.40.8017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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