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Chen X, Shi C, Buckey C, Stathakis S, Alkhatib H, Papanikolaou N. SU-GG-J-42: Development of an EPID-Based Machine and IMRT QA System. Med Phys 2010. [DOI: 10.1118/1.3468266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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177
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Gutierrez A, Stathakis S, Esquivel C, Liu Y, Zhai Y, Shi C, Papanikolaou N. Impact of pulse forming network and injection current parameters on output and energy variations of helical tomotherapy. JOURNAL OF B.U.ON. : OFFICIAL JOURNAL OF THE BALKAN UNION OF ONCOLOGY 2010; 15:373-377. [PMID: 20658738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
PURPOSE In this study, an experiment was devised to establish the dependency of the impact of pulse forming network (PFN) and injection current (IC) parameters on output and energy variations of helical tomotherapy (HT) on the radiation beam output and energy. METHODS HT has unique radiation beam characteristics due to the absence of a flattening filter. As with conventional linear accelerators, the machine output and energy should be within a + or - 2% tolerance according to published studies. However, because a dose servo is not utilized in a HT unit, these parameters may drift out of the + or - 2% tolerance due to various reasons such as high machine temperatures. With this in mind, physicists and engineers must adjust certain machine parameters to reset the output and energy to within the tolerance of the commissioned baseline. Two parameters commonly adjusted are: PFN voltage (V(PFN)) and IC voltage (V(IC)). RESULTS Results showed that the HT unit possesses different working zones defined by the V(PFN) and V(IC) parameter settings. The working zones were classified into 5 zones: 1) low dose rate zone - radiation dose rate much lower than nominal dose rate and machine cannot run due to low dose rate fault; 2) normal dose rate zone - dose rate is within tolerance of nominal dose rate and machine can run without dose rate fault; 3) dose rate failure during treatment zone - dose rate within the tolerance of the nominal dose rate however machine interrupts during treatment due to dose rate fault; 4) high dose rate zone - dose rate is higher than nominal dose rate and machine cannot run due to high dose rate fault; and 5) inoperable dose rate zone - dose rate is much higher than the nominal dose rate and machine cannot run. CONCLUSION The results of this study may provide a quick guide for physicists to adjust their HT unit V(PFN) and V(IC) values in order to reset the radiation beam output and energy back to within the tolerance of the commissioned baseline.
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Xia C, Lu M, Zhang Z, Meng Z, Zhang Z, Shi C. TLRs antiviral effect on hepatitis B virus in HepG2 cells. J Appl Microbiol 2010; 105:1720-7. [PMID: 19149768 DOI: 10.1111/j.1365-2672.2008.03896.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
AIMS A hepatoma cell line, HepG2, was used as a model system to detect Toll-like receptor (TLR) expression in hepatocytes and examine the antiviral effect on hepatitis B virus (HBV). METHODS AND RESULTS Toll-like receptor expression was detected in HepG2 cells by RT-PCR. The TLRs, which were strongly expressed in HepG2 cells, were stimulated with specific ligands. Interferon (IFN) response was evaluated poststimulation with Western blotting for signal transduction and activators of transcription-1. Furthermore, HepG2 cells were transiently transfected with wild-type HBV 1.3-fold over-length plasmid and treated with specific ligands at indicated times. Replication of HBV DNA, transcription of HBV RNA intermediate and expression of HBV antigens were respectively detected by Southern blotting, real time PCR, ELISA and Western blotting. Activation of different TLRs induced antiviral effects on HBV to varying degrees. CONCLUSIONS The TLRs, which were strongly expressed in HepG2 cells, could be stimulated with specific ligands. Activation of TLRs induced apparent production of antiviral cytokines such as IFN-alpha/beta and inhibited HBV lifecycle in the hepatocyte cell model. SIGNIFICANCE AND IMPACT OF THE STUDY Expression of TLRs in hepatocytes may be related to local immunity of liver and participate in the outcome of viral hepatitis.
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Anderson WS, Winberry J, Liu CC, Shi C, Lenz FA. Applying Microelectrode Recordings in Neurosurgery. CONTEMPORARY NEUROSURGERY 2010; 32:1-7. [PMID: 28316357 PMCID: PMC5350583 DOI: 10.1097/01.cne.0000369792.40458.fa] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
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180
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Shi C, Zhitomirsky I. Electrodeposition and capacitive behavior of films for electrodes of electrochemical supercapacitors. NANOSCALE RESEARCH LETTERS 2010; 5:518-523. [PMID: 20672082 PMCID: PMC2894232 DOI: 10.1007/s11671-009-9519-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Accepted: 12/17/2009] [Indexed: 05/29/2023]
Abstract
Polypyrrole films were deposited by anodic electropolymerization on stainless steel substrates from aqueous pyrrole solutions containing sodium salicylate and tiron additives. The deposition yield was studied under galvanostatic conditions. The amount of the deposited material was varied by the variation of deposition time at a constant current density. SEM studies showed the formation of porous films with thicknesses in the range of 0-3 μm. Cyclic voltammetry data for the films tested in 0.5 M Na2SO4 solutions showed capacitive behavior and high specific capacitance (SC) in a voltage window of 0.9 V. The films prepared from pyrrole solutions containing tiron showed better capacitive behavior compared to the films prepared from the solutions containing sodium salicylate. A highest SC of 254 F g-1 was observed for the sample with a specific mass of 89 μg cm-2 at a scan rate of 2 mV s-1. The SC decreased with an increasing film thickness and scan rate. The results indicated that the polypyrrole films deposited on the stainless steel substrates by anodic electropolymerization can be used as electrodes for electrochemical supercapacitors (ES).
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Shi C, Eom J, Vines D, De S, Xu G. Physics-based Patient-Specific Respiration Modeling for 4D Treatment Planning. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.1481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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182
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Shi C, Rui Q, Xu LL. Enzymatic properties of the 20S proteasome in wheat endosperm and its biochemical characteristics after seed imbibition. PLANT BIOLOGY (STUTTGART, GERMANY) 2009; 11:849-858. [PMID: 19796362 DOI: 10.1111/j.1438-8677.2009.00193.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The 20S proteasome from wheat (Triticum aestivum L., Yangmai 158) endosperm was purified to apparent homogeneity by three sequential centrifugations and gradient PAGE (GPAGE). The purified 20S proteasome clearly cleaved peptidyl-arylamide bonds in the model synthetic substrates Z-GGL-AMC and Z-GGR-AMC, which are used to reflect chymotrypsin-like and trypsin-like activity, respectively. For both substrates, the optimum pH was 8.0, but the optimum temperatures for chymotrypsin-like and trypsin-like activity were 55 degrees C and 37 degrees C, respectively. Both enzyme activities were clearly inhibited by MG115 and PMSF. Polyubiquitinated proteins remained constant from 0 to 7 days after seed imbibition, but caseinolytic activity and the amount of the 20S proteasome associated with the aleurone layer decreased from 1 to 2 days after imbibition (DAI), then increased from 2 to 4 DAI, and reached a maximum at 4 DAI that was retained until 7 DAI. An increase was seen in the mRNA level of the beta5 subunit of the 20S proteasome from 2 DAI, and caseinolytic activity and the amount of the 20S proteasome increased from 3 DAI onwards. In addition, the main storage proteins of the wheat endosperm could not be hydrolyzed by the 20S proteasome. The evidence suggests that the main role of the 20S proteasome may not be to degrade massive proteins of the wheat endosperm after seed imbibition.
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Liu Y, Shi C, Chen W, Xu G, Papanikolaou N. Tissue Composition Effect Investigated in Proton Therapy using Monte Carlo Models of Hounsfield Number Conversion and Cadaver-based Anatomical Data. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.1599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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184
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Shi C, Zhang H, Zhang T, Wang X, Bai B, Zhao Y, Zhang C, Xu Z. New Alternative Vaccine Component AgainstMycobacterium Tuberculosis- Heat Shock Protein 16.3 or its T-Cell Epitope. Scand J Immunol 2009; 70:465-74. [DOI: 10.1111/j.1365-3083.2009.02325.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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185
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Guo B, Papanikolaou N, Shi C. Monte Carlo-based Plan Verification for Electronic Brachytherapy: The Dosimetric Influence of Patient Boundary and Tissue Inhomogeneities. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.290] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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186
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Pagdonsolan M, Gutierrez A, Shi C, Papanikolaou N. Dosimetric Characterization of Whole Brain Radiotherapy (WBRT) using Helical Tomotherapy and Topotherapy. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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187
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Esquivel C, Stathakis S, Gutierrez A, Shi C, Smith M, Papanikolaou N. Clinical Experience in the use of Optically Stimulated Luminescent Dosimeters for Total Body Irradiation. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.1377] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Jiang Z, Dai J, Shi C, Zeng W, Jiang R, Tu W. Influence of patient-controlled i.v. analgesia with opioids on supraventricular arrhythmias after pulmonary resection. Br J Anaesth 2009; 103:364-8. [DOI: 10.1093/bja/aep172] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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189
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Shi C, Mavroidis P, Zhai Y, Xu J, Lind B, Papanikolaou N. EVALUATION OF IMRT DOSE DELIVERY USING THE CONCEPTS OF GAMMA INDEX AND BIOLOGICALLY EFFECTIVE UNIFORM DOSE. Radiother Oncol 2009. [DOI: 10.1016/s0167-8140(12)73237-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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190
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Holmes R, Shi C, Esquivel C, Gutierrez A, Stathakis S, He W, Papanikolaou N. SMARTARC™ IMRT DELIVERY: INFLUENCE OF ARC ANGLE AND DOSE RATE. Radiother Oncol 2009. [DOI: 10.1016/s0167-8140(12)73170-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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191
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Rodriguez S, Su F, Mavroidis P, Gutierrez A, Stathakis S, Esquivel C, Shi C, Papanikolaou N. BEUD/SECONDARY MALIGNANCY ANALYSIS: COMPARISON OF HT, MLC-BASED IMRT, AND CRT IN PROSTATE TREATMENT PLANNING. Radiother Oncol 2009. [DOI: 10.1016/s0167-8140(12)73230-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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192
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Su F, Mavroidis P, Ferreira BC, Shi C, Papanikolaou N. A RADIOBIOLOGICAL-BASED TOOLKIT FOR TREATMENT PLAN EVALUATION AND OUTCOME PREDICTION. Radiother Oncol 2009. [DOI: 10.1016/s0167-8140(12)73228-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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193
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Guo B, Papanikolaou N, Shi C. MONTE CARLO BASED PLAN VERIFICATION FOR ELECTRONIC BRACHYTHERAPY: THE DOSIMETRIC INFLUENCE OF PATIENT BOUNDARY AND TISSUE INHOMOGENEITIES. Radiother Oncol 2009. [DOI: 10.1016/s0167-8140(12)72862-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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194
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Guo B, Cheng C, Director B, Rusch T, Esquivel C, Stathakis S, Shi C, Papanikolaou N. SU-FF-T-05: A Monte Carlo Based Dose Calculation and Evaluation Toolkit for Electronic Brachytherapy: Feasibility of IMBT. Med Phys 2009. [DOI: 10.1118/1.3181476] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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195
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Calvo O, Gutiérrez A, Stathakis S, Mavroidis P, Moral S, Esquivel C, Shi C, Papanikolaou N. SU-FF-T-386: Validation of the Delta4 Dosimetry Phantom Against Ionometric Measurements. Med Phys 2009. [DOI: 10.1118/1.3181867] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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196
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Liu Y, Shi C, Xu X, Chen W, Jette D, Papanikolaou N. SU-FF-T-422: Dependency of Proton Dose On Tissue Composition Investigated Using Monte Carlo Models of Hounsfield Number Conversion and Cadaver-Based Anatomical Data. Med Phys 2009. [DOI: 10.1118/1.3181904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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197
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Su F, Shi C, Mavroidis P, Papanikolaou N. SU-FF-T-508: Utilizing Radiobiological Measures and Planned Adaptive Software to Evaluate Adaptive Tomotherapy Plans for Lung Cancer Patients. Med Phys 2009. [DOI: 10.1118/1.3182006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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198
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Esquivel C, Smith M, Stathakis S, Gutiérrez A, Shi C, Papanikolaou N. SU-FF-T-260: In Vivo Dose Measurements for Total Body Irradiation Using Optically Stimulated Luminescent Dosimeters. Med Phys 2009. [DOI: 10.1118/1.3181737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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199
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Vazquez L, Gutiérrez A, Stathakis S, Roland T, Esquivel C, Shi C, Mavroidis P, Papanikolaou N. SU-FF-T-623: Dosimetric Comparison Among 3D Conformal, IMRT, and Phase-Average Compensators for SBRT Treatment Planning. Med Phys 2009. [DOI: 10.1118/1.3182121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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200
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Hrycushko B, Li S, Shi C, Liu Y, Bao A. WE-D-BRB-05: Novel Post-Lumpectomy Breast Cancer Brachytherapy with the Capability of Simultaneous Focal Lymph Node Irradiation. Med Phys 2009. [DOI: 10.1118/1.3182519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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