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Zhong AY, Lui AJ, Kuznetsova S, Kallis K, Hussain T, Conlin CC, Do D, Rojo Domingo M, Manger R, Hua P, Karunamuni R, Kuperman J, Dale AM, Rakow-Penner R, Hahn ME, Moore KL, Ray X, Seibert TM. Clinical Impact of Contouring Variability for Prostate Cancer Tumor Boost. Int J Radiat Oncol Biol Phys 2023; 117:e455. [PMID: 37785460 DOI: 10.1016/j.ijrobp.2023.06.1644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) In the FLAME randomized phase III trial, adding a focal radiotherapy (RT) boost to tumors visible on MRI improved prostate cancer disease-free survival, local control, and regional/distant metastasis-free survival without increasing toxicity. In a prospective study (ReIGNITE RT Boost), we found substantial variability in radiation oncologists' attempts to contour prostate cancer tumors on MRI. Participants' accuracy and reliability improved when they used a quantitative MRI biomarker for cancer called the restriction spectrum imaging restriction score (RSIrs). Here, we measure the impact of radiation oncologists' tumor contour attempts on RT plans and predicted probability of biochemical failure. MATERIALS/METHODS A total of 44 radiation oncologists (participants) from multiple institutions contoured prostate tumors on 30 patient cases, some with only conventional MRI and some with conventional MRI plus RSIrs maps. We developed a knowledge-based planning automated algorithm to generate RT plans with focal tumor boost per the FLAME trial protocol: 77 Gy in 35 fractions to prostate and integrated boost up to 95 Gy to the focal target, provided no normal tissue constraints were violated. We applied this algorithm to each participant's tumor contour and compared dosimetric parameters to those achieved when using the expert-defined tumor (consensus of two radiologists and a radiation oncologist). The primary metric was dose covering 98% of the expert-defined tumor (D98%), which was associated with probability of biochemical failure in a model published with the FLAME trial. RESULTS In this preliminary analysis, 42 target volumes were analyzed from 20 participants and two patient cases: case 1 was contoured with conventional MRI alone and case 2 with RSIrs. All plans had adequate coverage of the prostate and met all key normal tissue constraints. For case 1 (without RSIrs), the expert's D98% was 87.1 Gy. By comparison, median D98% for participants was 82.2 Gy (IQR 77.8 - 84.6 Gy). Per the FLAME trial model, the predicted probability of biochemical failure at 7 years is 6% for the expert, but participants' plans yielded a median failure probability of 11% (IQR 18 - 9%). For case 2 (with RSIrs), the expert's D98% was 82.8 Gy, while median D98% for participants was 80.6 Gy (IQR 80.0 - 81.0 Gy). Predicted probability of biochemical failure is 12% for the expert-defined target and median 13% (IQR 14 - 13%) for participants. CONCLUSION Variability in radiation oncologists' prostate tumor contours can lead to clinically meaningful changes to focal RT boost plans. The probability of biochemical failure for one patient case increased from 6% to a median of 11% when using conventional MRI alone. Use of RSIrs may mitigate this problem by increasing the accuracy and reliability of radiation oncologists' tumor contours.
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Affiliation(s)
- A Y Zhong
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA
| | - A J Lui
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA
| | - S Kuznetsova
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA
| | - K Kallis
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA
| | - T Hussain
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA
| | - C C Conlin
- Department of Radiology, University of California San Diego, La Jolla, CA
| | - D Do
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA
| | - M Rojo Domingo
- Department of Bioengineering, University of California San Diego, La Jolla, CA
| | - R Manger
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA
| | - P Hua
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA
| | - R Karunamuni
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA
| | - J Kuperman
- Department of Radiology, University of California San Diego, La Jolla, CA
| | - A M Dale
- Department of Radiology, University of California San Diego, La Jolla, CA; Department of Neurosciences, University of California San Diego, La Jolla, CA
| | - R Rakow-Penner
- Department of Radiology, University of California San Diego, La Jolla, CA
| | - M E Hahn
- Department of Radiology, University of California San Diego, La Jolla, CA
| | - K L Moore
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA
| | - X Ray
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA
| | - T M Seibert
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA; Department of Radiology, University of California San Diego, La Jolla, CA
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Zhengshuai L, Yan F, Jinglin L, Hua P, Chunmei W. Glucocorticoid Receptor/HCN4 Channels Interaction in Spinal Dorsal Horn Participates in the Regulation of Neuropathic Pain after Peripheral Nerve Injury in Rats. Bull Exp Biol Med 2022; 173:594-601. [DOI: 10.1007/s10517-022-05594-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Indexed: 11/05/2022]
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Wu S, Yu Y, Liu C, Xia Z, Zhu P, Yan X, Li Y, Hua P, Li Q, Wang S, Zhang L. 719 Single-cell transcriptomics reveals lineage trajectory of human scalp hair follicle and informs mechanisms of hair graying. J Invest Dermatol 2022. [DOI: 10.1016/j.jid.2022.05.731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Wang Y, Hua P. OC08: A-wave serves as a diagnostic measure for demyelinating polyneuropathies. Clin Neurophysiol 2022. [DOI: 10.1016/j.clinph.2021.11.060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Moiseenko V, Atwood T, Coffey C, Hua P, Cornell M, Sanghvi P. PO-0808: Geometric and dosimetric evaluation of submandibular gland sparing following gland transfer. Radiother Oncol 2020. [DOI: 10.1016/s0167-8140(21)00825-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Cornell M, White G, O'Neal R, Hua P, Uhl J, Hartman P, Billoo A, McCall R, Zegers B. Pre-Clinical Validation and Efficiency Analysis of Semi-Automated Plan Documentation Process. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.1451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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7
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Rangarajan S, Rezonzew G, Chumley P, Fatima H, Golovko MY, Feng W, Hua P, Jaimes EA. COX-2-derived prostaglandins as mediators of the deleterious effects of nicotine in chronic kidney disease. Am J Physiol Renal Physiol 2019; 318:F475-F485. [PMID: 31841390 DOI: 10.1152/ajprenal.00407.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Tobacco smoking has been identified as a risk factor in the progression of chronic kidney disease (CKD). In previous studies, we showed that nicotine induces cyclooxygenase (COX)-2 expression in vivo and in vitro and that the administration of nicotine in vivo worsens the severity of renal injury in a model of subtotal renal ablation. In the present study, we tested the role of COX-2-derived prostaglandins on the deleterious effects of nicotine in CKD. Sham and 5/6 nephrectomy (5/6Nx) rats received tap water or nicotine (100 μg/mL) in the drinking water for 12 wk. Additional groups also systemically received the COX-2 inhibitor NS-398 (1.5 mg·kg-1·day-1 via osmotic minipump). The administration of nicotine worsened renal injury and proteinuria in 5/6Nx rats and increased proteinuria in sham rats. 5/6Nx rats had increased cortical production of the prostaglandins PGE2, PGI2, PGD2, and PGF2α and of thromboxane A2. In these rats, nicotine reduced the production of all prostaglandins examined except thromboxane A2. Treatment with the COX-2 inhibitor NS-398 resulted in complete inhibition of all prostaglandins studied and ameliorated renal injury and proteinuria in 5/6Nx rats on nicotine but not in 5/6 Nx rats on tap water. Nicotine also reduced the expression of megalin in all groups examined, and this was partially prevented by COX-2 inhibition. In the present study, we showed that in CKD, nicotine worsens renal injury at least in part by producing an imbalance in the production of prostaglandins. This imbalance in the production of prostaglandins likely plays a role in the deleterious effects of smoking on the progression of CKD.
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Affiliation(s)
- S Rangarajan
- Renal Division, University of Alabama at Birmingham, Birmingham, Alabama
| | - G Rezonzew
- Renal Division, University of Alabama at Birmingham, Birmingham, Alabama
| | - P Chumley
- Renal Division, University of Alabama at Birmingham, Birmingham, Alabama
| | - H Fatima
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama
| | - M Y Golovko
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota
| | - W Feng
- Renal Division, University of Alabama at Birmingham, Birmingham, Alabama
| | - P Hua
- Renal Division, University of Alabama at Birmingham, Birmingham, Alabama
| | - E A Jaimes
- Renal Service, Memorial Sloan Kettering Cancer Center and Weill Cornell Medical College, New York, New York
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Cacciottolo TM, Perikari A, van der Klaauw A, Henning E, Stadler LKJ, Keogh J, Farooqi IS, Tenin G, Keavney B, Ryan E, Budd R, Bewley M, Coelho P, Rumsey W, Sanchez Y, McCafferty J, Dockrell D, Walmsley S, Whyte M, Liu Y, Choy MK, Tenin G, Abraham S, Black G, Keavney B, Ford T, Stanley B, Good R, Rocchiccioli P, McEntegart M, Watkins S, Eteiba H, Shaukat A, Lindsay M, Robertson K, Hood S, McGeoch R, McDade R, Sidik N, McCartney P, Corcoran D, Collison D, Rush C, McConnachie A, Touyz R, Oldroyd K, Berry C, Gazdagh G, Diver L, Marshall J, McGowan R, Ahmed F, Tobias E, Curtis E, Parsons C, Maslin K, D'Angelo S, Moon R, Crozier S, Gossiel F, Bishop N, Kennedy S, Papageorghiou A, Fraser R, Gandhi S, Prentice A, Inskip H, Godfrey K, Schoenmakers I, Javaid MK, Eastell R, Cooper C, Harvey N, Watt ER, Howden A, Mirchandani A, Coelho P, Hukelmann JL, Sadiku P, Plant TM, Cantrell DA, Whyte MKB, Walmsley SR, Mordi I, Forteath C, Wong A, Mohan M, Palmer C, Doney A, Rena G, Lang C, Gray EH, Azarian S, Riva A, Edwards H, McPhail MJW, Williams R, Chokshi S, Patel VC, Edwards LA, Page D, Miossec M, Williams S, Monaghan R, Fotiou E, Santibanez-Koref M, Keavney B, Badat M, Mettananda S, Hua P, Schwessinger R, Hughes J, Higgs D, Davies J. Scientific Business Abstracts of the 113th Annual Meeting of the Association of Physicians of Great Britain and Ireland. QJM 2019; 112:724-729. [PMID: 31505685 DOI: 10.1093/qjmed/hcz175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | - A Perikari
- University of Cambridge Metabolic Research Laboratories
| | | | - E Henning
- University of Cambridge Metabolic Research Laboratories
| | - L K J Stadler
- University of Cambridge Metabolic Research Laboratories
| | - J Keogh
- University of Cambridge Metabolic Research Laboratories
| | - I S Farooqi
- University of Cambridge Metabolic Research Laboratories
| | - G Tenin
- From University of Manchester
| | | | - E Ryan
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - R Budd
- Department of Infection Immunity and Cardiovascular Disease, The Florey Institute for Host-Pathogen Interactions, University of Sheffield
| | - M Bewley
- Department of Infection Immunity and Cardiovascular Disease, The Florey Institute for Host-Pathogen Interactions, University of Sheffield
| | - P Coelho
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - W Rumsey
- Stress and Repair Discovery Performance Unit, Respiratory Therapy Area
| | - Y Sanchez
- Stress and Repair Discovery Performance Unit, Respiratory Therapy Area
| | - J McCafferty
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - D Dockrell
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - S Walmsley
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - M Whyte
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - Y Liu
- From the University of Manchester
| | - M-K Choy
- From the University of Manchester
| | - G Tenin
- From the University of Manchester
| | | | - G Black
- From the University of Manchester
| | | | - T Ford
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | | | - R Good
- Golden Jubilee National Hospital
| | - P Rocchiccioli
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - M McEntegart
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | | | - H Eteiba
- Golden Jubilee National Hospital
| | | | | | | | - S Hood
- Golden Jubilee National Hospital
| | | | - R McDade
- Golden Jubilee National Hospital
| | - N Sidik
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - P McCartney
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - D Corcoran
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - D Collison
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - C Rush
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | | | - R Touyz
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
| | - K Oldroyd
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - Colin Berry
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - G Gazdagh
- School of Medicine, Dentistry & Nursing, College of Medical, Veterinary and Life Sciences, University of Glasgow
| | - L Diver
- West of Scotland Regional Genetics Service, Laboratory Medicine Building, Queen Elizabeth University Hospital
| | - J Marshall
- Institute of Cancer Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow
| | - R McGowan
- West of Scotland Regional Genetics Service, Laboratory Medicine Building, Queen Elizabeth University Hospital
| | - F Ahmed
- Developmental Endocrinology Research Group, Royal Hospital for Children, University of Glasgow
| | - E Tobias
- Academic Unit of Medical Genetics and Clinical Pathology, Laboratory Medicine Building, Queen Elizabeth University Hospital, University of Glasgow
| | - E Curtis
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - C Parsons
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - K Maslin
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - S D'Angelo
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - R Moon
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - S Crozier
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - F Gossiel
- Academic Unit of Bone Metabolism, University of Sheffield
| | - N Bishop
- Academic Unit of Child Health, University of Sheffield
| | - S Kennedy
- Nuffield Department of Women's & Reproductive Health, John Radcliffe Hospital, University of Oxford
| | - A Papageorghiou
- Nuffield Department of Women's & Reproductive Health, John Radcliffe Hospital, University of Oxford
| | - R Fraser
- Department of Obstetrics and Gynaecology, Sheffield Hospitals NHS Trust, University of Sheffield
| | - S Gandhi
- Department of Obstetrics and Gynaecology, Sheffield Hospitals NHS Trust, University of Sheffield
| | | | - H Inskip
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - K Godfrey
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - I Schoenmakers
- Department of Medicine, Faculty of Medicine and Health Sciences, University of East Anglia
| | - M K Javaid
- NIHR Oxford Biomedical Research Centre, University of Oxford
| | - R Eastell
- Academic Unit of Bone Metabolism, University of Sheffield
| | - C Cooper
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - N Harvey
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | | | - A Howden
- School of Life Sciences, University of Dundee
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - E H Gray
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - S Azarian
- Institute of Hepatology, Foundation for Liver Research
| | - A Riva
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - H Edwards
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - M J W McPhail
- School of Immunology and Microbial Sciences, King's College London
- Institute of Liver Studies & Transplantation, King's College Hospital
| | - R Williams
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - S Chokshi
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - V C Patel
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
- Institute of Liver Studies & Transplantation, King's College Hospital
| | - L A Edwards
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - D Page
- University of Manchester
- Manchester Metropolitan University
| | - M Miossec
- Manchester Metropolitan University
- University of Newcastle
| | | | | | | | | | | | - M Badat
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
| | - S Mettananda
- Department of Paediatrics, Faculty of Medicine, University of Kelaniya
| | - P Hua
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
| | - R Schwessinger
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
| | - J Hughes
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
| | - D Higgs
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
| | - J Davies
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
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Schwartz M, Schoenbrun R, Hua P, Tomita S, Orfanelli T, Overbey J, Ascher-Walsh C, Blank S, Loudon H. Use of vaginal chlorhexidine antisepsis prior to hysterectomy to reduce surgical site infection. Gynecol Oncol 2019. [DOI: 10.1016/j.ygyno.2019.04.449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Chong W, Hua P, Gaigbe-Togbe B, Overbey J, Ascher-Walsh C. 28: Incidence and predictors of explantation of sacral neuromodulator in a single urban medical center. Am J Obstet Gynecol 2019. [DOI: 10.1016/j.ajog.2019.01.058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Shang S, Zhang M, Zhao Y, Dang W, Hua P, Zhang S, Wang Z. Development and validation of a novel 13‐plex
PCR
system for commonly used short tandem repeats in horses (
Equus caballus
). Equine Vet J 2018; 51:688-695. [DOI: 10.1111/evj.13047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 11/13/2018] [Indexed: 11/30/2022]
Affiliation(s)
- S. Shang
- Institute of Equine Sciences College of Animal Science and Veterinary Medicine Shenyang Agricultural University Shenyang PR China
- College of Food Science Shenyang Agricultural University Shenyang PR China
| | - M. Zhang
- College of Economics and Management Shenyang Agricultural University Shenyang PR China
| | - Y. Zhao
- Institute of Equine Sciences College of Animal Science and Veterinary Medicine Shenyang Agricultural University Shenyang PR China
| | - W. Dang
- Institute of Equine Sciences College of Animal Science and Veterinary Medicine Shenyang Agricultural University Shenyang PR China
| | - P. Hua
- School of Ecological and Environmental Sciences East China Normal University Shanghai PR China
| | - S. Zhang
- Institute of Equine Sciences College of Animal Science and Veterinary Medicine Shenyang Agricultural University Shenyang PR China
| | - Z. Wang
- Institute of Equine Sciences College of Animal Science and Veterinary Medicine Shenyang Agricultural University Shenyang PR China
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Charlton JL, Koppel S, Hua P, St. Louis RM, Di Stefano M, Darzins P, Odell M, Porter MM. CHARACTERISTICS OF LOW AND HIGH DISTANCE DRIVERS: FINDINGS FROM THE OZCANDRIVE/CANDRIVE OLDER DRIVER COHORT STUDY. Innov Aging 2018. [DOI: 10.1093/geroni/igy023.2077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- J L Charlton
- Monash University Accident Research Centre, Melbourne, Victoria, Australia
| | - S Koppel
- Monash University Accident Research Centre, Melbourne, Victoria, Australia
| | - P Hua
- Monash University Accident Research Centre, Melbourne, Victoria, Australia
| | - R M St. Louis
- Monash University Accident Research Centre, Melbourne, Victoria, Australia
| | - M Di Stefano
- La Trobe University, Melbourne, Victoria, Australia
| | - P Darzins
- Monash University Eastern Health Clinical School, Melbourne, Victoria, Australia
| | - M Odell
- Victorian Institute of Forensic Medicine, Southback, Victoria, Australia
| | - M M Porter
- Faculty of Kinesiology and Recreation Management, and Centre on Aging, University of Manitoba, Winnipeg, Manitoba, Canada
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Koppel S, Charlton JL, Hua P, Liu PY, Pham H, Stephan K, Logan D, St. Louis RM. ARE OLDER DRIVERS’ DRIVING PATTERNS DURING AN ON-ROAD DRIVING TASK REPRESENTATIVE OF THEIR REAL-WORLD DRIVING? Innov Aging 2018. [DOI: 10.1093/geroni/igy023.2078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- S Koppel
- Monash University Accident Research Centre, Melbourne, Victoria, Australia
| | - J L Charlton
- Monash University Accident Research Centre, Melbourne, Victoria, Australia
| | - P Hua
- BPsych(Hons), Monash University Accident Research Centre, Melbourne, Victoria, Australia
| | - P Y Liu
- Monash University Accident Research Centre, Melbourne, Victoria, Australia
| | - H Pham
- Monash University Accident Research Centre, Melbourne, Victoria, Australia
| | - K Stephan
- Monash University Accident Research Centre, Melbourne, Victoria, Australia
| | - D Logan
- Monash University Accident Research Centre, Melbourne, Victoria, Australia
| | - R M St. Louis
- Monash University Accident Research Centre, Melbourne, Victoria, Australia
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Koppel S, Charlton JL, Hua P, Liu PY, Pham H, Stephan K, Logan D, St Louis RM, Gao G, Griffiths D, Williams G, Witharanage T, Di Stefano M, Darzins P, Odell M, Porter MM, Mazer B, Gelinas I, Vrkljan B, Marshall S. Are older drivers' driving patterns during an on-road driving task representative of their real-world driving patterns? Traffic Inj Prev 2018; 19:S173-S175. [PMID: 30841798 DOI: 10.1080/15389588.2018.1532219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
OBJECTIVE The current study investigated whether older drivers' driving patterns during a customized on-road driving task were representative of their real-world driving patterns. METHODS Two hundred and eight participants (male: 68.80%; mean age = 81.52 years, SD = 3.37 years, range = 76.00-96.00 years) completed a customized on-road driving task that commenced from their home and was conducted in their own vehicle. Participants' real-world driving patterns for the preceding 4-month period were also collected via an in-car recording device (ICRD) that was installed in each participant's vehicle. RESULTS During the 4-month period prior to completing the on-road driving task, participants' median real-world driving trip distance was 2.66 km (interquartile range [IQR] = 1.14-5.79 km) and their median on-road driving task trip distance was 4.41 km (IQR = 2.83-6.35 km). Most participants' on-road driving task trip distances were classified as representative of their real-world driving trip distances (95.2%, n = 198). CONCLUSIONS These findings suggest that most older drivers were able to devise a driving route that was representative of their real-world driving trip distance. Future research will examine whether additional aspects of the on-road driving task (e.g., average speed, proportion of trips in different speed zones) are representative of participants' real-world driving patterns.
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Affiliation(s)
- S Koppel
- a Monash University Accident Research Centre , Victoria , Australia
| | - J L Charlton
- a Monash University Accident Research Centre , Victoria , Australia
| | - P Hua
- a Monash University Accident Research Centre , Victoria , Australia
| | - P Y Liu
- a Monash University Accident Research Centre , Victoria , Australia
| | - H Pham
- a Monash University Accident Research Centre , Victoria , Australia
| | - K Stephan
- a Monash University Accident Research Centre , Victoria , Australia
| | - D Logan
- a Monash University Accident Research Centre , Victoria , Australia
| | - R M St Louis
- a Monash University Accident Research Centre , Victoria , Australia
| | - G Gao
- a Monash University Accident Research Centre , Victoria , Australia
| | - D Griffiths
- a Monash University Accident Research Centre , Victoria , Australia
| | - G Williams
- a Monash University Accident Research Centre , Victoria , Australia
| | - T Witharanage
- a Monash University Accident Research Centre , Victoria , Australia
| | | | - P Darzins
- c Eastern Health , Victoria, Australia
| | - M Odell
- d Victorian Institute of Forensic Medicine , Victoria, Australia
| | - M M Porter
- e Faculty of Kinesiology and Recreation Management, and Centre on Aging , University of Manitoba , Canada
| | - B Mazer
- f McGill University , Winnipeg, Canada
| | - I Gelinas
- f McGill University , Winnipeg, Canada
| | - B Vrkljan
- g McMaster University , Hamilton, Canada
| | - S Marshall
- h Ottawa Hospital Research Institute , Ottawa, Canada
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15
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Hernandez D, Kronsteiner B, Tarunina M, Hua P, Partington L, Baboo J, Rologi E, Hassan E, Chan A, Watt S, Choo Y. Using CombiCult® screening platform to discover optimal protocols for ex vivo expansion of hematopoietic stem cells from cord blood and bone marrow. Cytotherapy 2017. [DOI: 10.1016/j.jcyt.2017.02.121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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16
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Patil A, Hua P, Sellwood M, Jellinek D, Carroll T, Chen B, Collis S. OP21IDENTIFICATION OF NOVEL SMALL MOLECULE INHIBITORS OF THE FANCONI ANAEMIA DNA REPAIR PATHWAY AS A MEANS TO SENSITISES GLIOBLASTOMAS TO CHEMOTHERAPEUTIC AGENTS. Neuro Oncol 2015. [DOI: 10.1093/neuonc/nov283.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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17
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Yang S, Hua P, Shang X, Cui Z, Zhong S, Gong G, William Humphreys G. Deficiency of brain structural sub-network underlying post-ischaemic stroke apathy. Eur J Neurol 2014; 22:341-7. [PMID: 25319873 DOI: 10.1111/ene.12575] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 08/25/2014] [Indexed: 11/29/2022]
Affiliation(s)
- S. Yang
- Department of Experimental Psychology; University of Oxford; Oxford UK
- Department of Neurology; Guangzhou First People's Hospital; Guangzhou Medical University; Guangzhou China
| | - P. Hua
- Department of Cadio-vascular surgery; Sun Yat-sen Memorial Hospital; Sun Yat-sen University; Guangzhou China
| | - X. Shang
- Department of Neurology; Guangzhou First People's Hospital; Guangzhou Medical University; Guangzhou China
| | - Z. Cui
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research; Beijing Normal University; Beijing China
| | - S. Zhong
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research; Beijing Normal University; Beijing China
| | - G. Gong
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research; Beijing Normal University; Beijing China
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18
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Liu W, Hua P, Zhao Y, Chen L, Zhang N, Kuo SH. Association Study between Clock Genes Variants and Depression in Parkinson's Disease in Han Chinese (PD4.012). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.pd4.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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19
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Hua P, Pinsonneault L, Déry V. Modalités des interventions efficaces dans le traitement de l'obésité chez les enfants et les adolescents. Can J Diabetes 2011. [DOI: 10.1016/s1499-2671(11)52142-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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20
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Zhang HZ, Lin XG, Hua P, Wang M, Ao X, Xiong LH, Wu C, Guo JJ. The study of the tumor stem cell properties of CD133+CD44+ cells in the human lung adenocarcinoma cell line A549. Cell Mol Biol (Noisy-le-grand) 2010; 56 Suppl:OL1350-OL1358. [PMID: 20937222] [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] [Received: 08/04/2009] [Accepted: 07/29/2010] [Indexed: 05/30/2023]
Abstract
We studied the tumor stem cell properties of the CD133+CD44+ subpopulation in the human lung adenocarcinoma cell line A549. A549 cells were classified into subpopulations based on differential expression patterns for CD133 and CD44. Cells from different subpopulations were cultured and subcutaneously injected into 32 nude mice. Our results as following, (1) The majority of A549 cells died, whereas only about 4.11% of cells divided and proliferated to form cell clones. (2) The expression of CD133 and CD44 in proliferative cancer cells was statistically significantly different from that in normal A549 cells (p < 0.001). (3) Cell proliferation in group A (CD133+CD44+) was the fastest among all groups. Cell proliferation in A549 cells was slower than in group A but faster than in groups B (CD133-CD44-), C (CD133-CD44+), and D (CD133+CD44-). (4) The tumorigenic capacity in cells from group A was significantly higher than that in cells from groups B (p<0.001), C (p<0.001) and D (p<0.04). In conclusion, CD133+CD44+ cells in the adenocarcinoma cell line A549 have expressive significant cancer stem cell properties with continuous proliferative capacity and differentiation potential.
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Affiliation(s)
- H Z Zhang
- Cardio-Thoracic surgery of the Sun Yat-sen Memorial Hospital, Sun Yat-sen university, Guangzhou, China
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21
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Xing Z, Tan F, Hua P, Sun L, Xu G, Zhang Q. Characterization of the main effects, epistatic effects and their environmental interactions of QTLs on the genetic basis of yield traits in rice. Theor Appl Genet 2002; 105:248-257. [PMID: 12582526 DOI: 10.1007/s00122-002-0952-y] [Citation(s) in RCA: 174] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2001] [Accepted: 10/16/2001] [Indexed: 05/21/2023]
Abstract
Main effects, epistatic effects and their environmental interactions of QTLs are all important genetic components of quantitative traits. In this study, we analyzed the main effects, epistatic effects of the QTLs, and QTL by environment interactions (QEs) underlying four yield traits, using a population of 240 recombinant inbred lines from a cross between two rice varieties tested in replicated field trials. A genetic linkage map with 220 DNA marker loci was constructed. A mixed linear model approach was used to detect QTLs with main effects, QTLs involved in digenic interactions and QEs. In total, 29 QTLs of main effects, and 35 digenic interactions involving 58 loci were detected for the four traits. Thirteen QTLs with main effects showed QEs; no QE was detected for the QTLs involved in epistatic interactions. The amount of variations explained by the QTLs of main effect were larger than the QTLs involved in epistatic interactions, which in turn were larger than QEs for all four traits. This study illustrates the ability of the analysis to assess the genetic components underlying the quantitative traits, and demonstrates the relative importance of the various components as the genetic basis of yield traits in this population.
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Affiliation(s)
- Z. Xing
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
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22
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Deng MA, Zhou Y, Hua P, Tan WS. [Growth and metabolism of human skin fibroblasts cultured on microcarriers]. Sheng Wu Gong Cheng Xue Bao 2001; 17:336-8. [PMID: 11517614] [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: 02/21/2023]
Abstract
Human foreskin fibroblasts were cultured in vitro on microcarriers in spinners and traditional static flasks. The cultured cells obtained with these approaches were compared in cell shape, cell growth, cell production, and the metabolisms of glucose, lactate, and ammonium. The cells from microcarrier cultures through medium exchange were 8 times more than those from traditional static flasks. It was found that the specific growth rate and specific glucose consumption rate in microcarrier spinner cultures were 0.64/d-1 and 5.56 mmol/10(9) cell/d, respectively, higher than those in static flask cultures. However, the average lactate yield on glucose consumption in spinner cultures was only 0.955 mmol/mmol, lower than that in static flask cultures, 1. 125 mmol/mmol. This indicated that the energy metabolism in spinner cultures was significantly more efficient than that in static flasks. The experimental results from this work suggest that the microcarrier culture system is a suitable way to expand the seeding cells for tissue engineering, due to its ideal cultivation environment provided.
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Affiliation(s)
- M A Deng
- State Key Laboratory of Bioreactor Engineering, ECUST, Shanghai 200237, China
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23
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Abstract
To identify the causative agent of canine ehrlichiosis that has occurred in the suburbs of Guangzhou, China, since 1998, the 16S rRNA gene was amplified and sequenced. Two sequences of 1,482 and 1,483 base pairs were obtained and named as Gzh981 and Gzh982, respectively. The level of similarity of these two was 91.50%, and Gzh981 closely resembled the 16S rRNA gene of Ehrlichia canis, whereas Gzh982 resembled Ehrlichia platys. We therefore conclude that E. canis and E. platys together caused recent outbreaks of canine ehrlichiosis in China.
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Affiliation(s)
- P Hua
- The Medical Research Institute in Guangzhou, PR. China
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24
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Zhou YJ, Tan WS, Zhao J, Hua P, Sun XM, Yu JT. [On-line measurement of oxygen uptake rate in the cultivation of Vero cells using the dynamic method]. Sheng Wu Gong Cheng Xue Bao 2000; 16:525-7. [PMID: 11051834] [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: 02/18/2023]
Abstract
The oxygen uptake rate(OUR) during the cultivation of Vero cells in 1.5 L CelliGen bioreactor was on-line determined using the dynamic method. The results showed that the cell growth and metabolic state during the exponential growth phase was lineally related to the OUR. This implies that the on-line measurement of OUR can be used to promptly monitor the physiological state of cultured cells and to efficiently avoid contamination because of frequent sampling in the large-scale cultivation of mammalian cells.
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Affiliation(s)
- Y J Zhou
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai
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25
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Densmore CL, Orson FM, Xu B, Kinsey BM, Waldrep JC, Hua P, Bhogal B, Knight V. Aerosol delivery of robust polyethyleneimine-DNA complexes for gene therapy and genetic immunization. Mol Ther 2000; 1:180-8. [PMID: 10933929 DOI: 10.1006/mthe.1999.0021] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Aerosol delivery of plasmid DNA to the lungs offers the possibility of direct application of gene preparations to pulmonary surfaces as a means of treating a variety of genetic pulmonary disorders. However, the process of jet nebulization rapidly degrades naked DNA, viral vectors, and many lipid-based formulations. While complexing DNA with cationic lipids has been shown to significantly stabilize plasmid DNA, losses of biological activity often occur during nebulization, severely limiting the efficiency of aerosol delivery of many such complexes. In conjunction with the design of aerosol delivery systems appropriate for DNA delivery, we have developed formulations using polyethyleneimine (PEI, a polycationic polymer) and DNA that result in a high level of pulmonary transfection (10- to 100-fold greater than many cationic lipids) and are stable during nebulization. In addition, these PEI-based formulations exhibit a high degree of specificity for the lungs. The properties of PEI-based formulations that make them resistant to nebulization and efficient as DNA delivery vectors for pulmonary sites have been investigated. Potential applications of this technology, including the use of aerosolized PEI-DNA for genetic immunization, are discussed.
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Affiliation(s)
- C L Densmore
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas 77030, USA.
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26
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Sun X, Zhang Y, Tan W, Zhou Y, Hua P. Attachment kinetics of vero cells onto CT-3 microcarriers. J Biosci Bioeng 2000; 90:32-6. [PMID: 16232814 DOI: 10.1016/s1389-1723(00)80030-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2000] [Accepted: 04/03/2000] [Indexed: 11/19/2022]
Abstract
The effects of cell seeding density, microcarrier concentration, agitation speed and age of seeding cells on the rate of cell attachment to the surface of CT-3 microcarriers were investigated. It was shown that the attachment followed first-order kinetics. When either the cell seeding density or the microcarrier concentration was increased, the kinetic constant increased due to an increase in the probability of collision between cells and microcarriers. However, at higher microcarrier concentrations, the increase in the kinetic constant with increasing microcarrier concentration was not significant. Cell attachment was decelerated upon increasing the agitation speed because of the shorter cell-microcarrier contact time. In addition, it was also demonstrated that cell attachment occurred more efficiently when seeding cells from the middle or early exponential growth phase were used. The process of cell attachment onto CT-3 microcarriers was investigated, and our results showed that the attachment stage was the rate-limiting step. These results will facilitate the optimization of the Vero cell culture process.
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Affiliation(s)
- X Sun
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
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27
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Ahern-Djamali SM, Bachmann C, Hua P, Reddy SK, Kastenmeier AS, Walter U, Hoffmann FM. Identification of profilin and src homology 3 domains as binding partners for Drosophila enabled. Proc Natl Acad Sci U S A 1999; 96:4977-82. [PMID: 10220404 PMCID: PMC21802 DOI: 10.1073/pnas.96.9.4977] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [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: 11/18/2022] Open
Abstract
Drosophila Enabled (Ena) was first identified as a genetic suppressor of mutations in the Abelson tyrosine kinase and subsequently was shown to be a member of the Ena/vasodilator-stimulated phosphoprotein family of proteins. All members of this family have a conserved domain organization, bind the focal adhesion protein zyxin, and localize to focal adhesions and stress fibers. Members of this family are thought to be involved in the regulation of cytoskeleton dynamics. The Ena protein sequence has multiple poly-(L-proline) residues with similarity to both profilin and src homology 3 binding sites. Here, we show that Ena can bind directly to the Drosophila homolog of profilin, chickadee. Furthermore, Ena and profilin were colocalized in spreading cultured cells. We report that the proline-rich region of Ena is responsible for this interaction as well as for mediating binding to the src homology 3 domain of the Abelson tyrosine kinase. These data support the hypothesis that Ena provides a regulated link between signal transduction and cytoskeleton assembly in the developing Drosophila embryo.
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Affiliation(s)
- S M Ahern-Djamali
- McArdle Laboratory for Cancer Research and Laboratory of Genetics, University of Wisconsin Medical School, 1400 University Avenue, Madison, WI 53706, USA.
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28
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Orson FM, Klysik J, Bergstrom DE, Ward B, Glass GA, Hua P, Kinsey BM. Triple helix formation: binding avidity of acridine-conjugated AG motif third strands containing natural, modified and surrogate bases opposed to pyrimidine interruptions in a polypurine target. Nucleic Acids Res 1999; 27:810-6. [PMID: 9889277 PMCID: PMC148251 DOI: 10.1093/nar/27.3.810] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [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: 11/12/2022] Open
Abstract
A critical issue for the general application of triple-helix-forming oligonucleotides (TFOs) as modulators of gene expression is the dramatically reduced binding of short TFOs to targets that contain one or two pyrimidines within an otherwise homopurine sequence. Such targets are often found in gene regulatory regions, which represent desirable sites for triple helix formation. Using intercalator-conjugated AG motif TFOs, we compared the efficacy and base selectivity of 13 different bases or base surrogates in opposition to pyrimidines and purines substituted into selected positions within a paradigm 15-base polypurine target sequence. We found that substitutions closer to the intercalator end of the TFO (positions 4-6) had a more deleterious effect on the dissociation constant (K d) than those farther away (position 11). Opposite T residues at position 11, 3-nitropyrrole or cytosine in the TFO provided adequate binding avidity for useful triplex formation (K ds of 55 and 110 nM, respectively). However, 3-nitropyrrole was more base selective than cytosine, binding to T >/=4 times better than to A, G or C. None of the TFOs tested showed avid binding when C residues were in position 11, although the 3-nitropyrrole-containing TFO bound with a K d of 200 nM, significantly better than the other designs. Molecular modeling showed that the 3-nitropyrrole.T:A triad is isomorphous with the A.A:T triad, and suggests novel parameters for evaluating new base triad designs.
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Affiliation(s)
- F M Orson
- The Veterans Affairs Medical Center, Department of Internal Medicine, Baylor College of Medicine, Building 109, Room 226, VAMC, 2002 Holcombe, Houston, TX 77030, USA.
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Klysik J, Kinsey BM, Hua P, Glass GA, Orson FM. A 15-base acridine-conjugated oligodeoxynucleotide forms triplex DNA with its IL-2R alpha promoter target with greatly improved avidity. Bioconjug Chem 1997; 8:318-26. [PMID: 9177837 DOI: 10.1021/bc970017f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [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: 02/04/2023]
Abstract
Attachment of 6,9-diamino-2-methoxyacridine to the 5' end of a purine-rich oligodeoxynucleotide targeting a 15 bp oligopurine oligopyrimidine stretch in the promoter region of the interleukin-2 receptor alpha chain (IL-2R alpha) gene results in an approximately 500-fold increase in its triplex forming avidity as determined by both band shift assay and DMS footprinting (Kd lowered from 2.5 microM to 5 nM). This oligonucleotide participates in Mg(2+)-dependent three-stranded DNA formation in which it is oriented antiparallel relative to the purine strand of the target duplex as determined by acridine moiety sensitized photoreactivity with the target duplex DNA. The oligonucleotides used in these studies were synthesized with a 3-amino-2-hydroxypropyl group at the 3' end to protect against exonucleolytic degradation for future in vivo applications. The 3'-amino group underwent partial removal, probably during the NaOH deprotection step. Both the 3'-amino and the 3'-free forms of the oligo have the same binding avidity and specificity. The interaction of the third strand with its target is sequence specific and can be essentially abolished by a point G-->T transversion 4 bases away from the 3' end of the target oligopurine block or severely reduced by other mutations within the target duplex. Thus, the attachment of the acridine moiety to the 5' end of the oligonucleotide does not seem to substantially compromise the sequence specificity of binding. Additionally, the oligonucleotide composed of G and A nucleotides was found to be superior to the oligonucleotide containing G and T residues since the difference in avidity of binding to the same target site was 17-fold.
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Affiliation(s)
- J Klysik
- Veterans Affairs Medical Center Research Center on AIDS and HIV Infections, Houston, Texas, USA
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30
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Rudolph D, Gross CJ, Akovali YA, Baktash C, Döring J, Durham FE, Hua P, Johns GD, Korolija M, LaFosse DR, Lee IY, Macchiavelli AO, Rathbun W, Sarantites DG, Stracener DW, Tabor SL, Afanasjev AV, Ragnarsson I. Shell-model influence in the rotational nucleus 86Mo. Phys Rev C Nucl Phys 1996; 54:117-124. [PMID: 9971325 DOI: 10.1103/physrevc.54.117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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31
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Sun Y, Xu G, Du J, Zhou Y, Zeng R, Fu X, Hua P, Zhang Y. Observation of a three-dimensional vortex-line liquid in a highly c-axis-oriented (Bi,Pb)2Sr2Ca2Cu3Ox silver-sheathed tape. Phys Rev B Condens Matter 1996; 54:1382-1385. [PMID: 9985410 DOI: 10.1103/physrevb.54.1382] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [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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32
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Jin H, Baktash C, Brinkman MJ, Gross CJ, Sarantites DG, Lee IY, Cederwall B, Cristancho F, Döring J, Durham FE, Hua P, Johns GD, Korolija M, LaFosse DR, Landulfo E, Macchiavelli AO, Rathbun W, Saladin JX, Stracener DW, Tabor SL, Werner TR. Identification and Quadrupole-Moment Measurement of a Superdeformed Band in 84Zr. Phys Rev Lett 1995; 75:1471-1474. [PMID: 10060306 DOI: 10.1103/physrevlett.75.1471] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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33
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LaFosse DR, Sarantites DG, Baktash C, Hua P, Cederwall B, Fallon P, Gross CJ, Jin H, Korolija M, Lee IY, Macchiavelli AO, Maier MR, Rathbun W, Stracener DW, Werner TR. Evidence for hyperdeformation in 147Gd. Phys Rev Lett 1995; 74:5186-5189. [PMID: 10058704 DOI: 10.1103/physrevlett.74.5186] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Lustig RH, Hua P, Smith LS, Wang C, Chang C. An in vitro model for the effects of androgen on neurons employing androgen receptor-transfected PC12 cells. Mol Cell Neurosci 1994; 5:587-96. [PMID: 7704433 DOI: 10.1006/mcne.1994.1072] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [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: 01/26/2023] Open
Abstract
Androgen alters neurite outgrowth, synaptic organization, and cell survival in various portions of the brain and spinal cord. However, examination of the specific effects of androgen on neurons in vivo has been difficult. Previously, an in vitro model for the effects of estrogen on neurons was developed and characterized, using an estrogen receptor (ER)-transfected PC12 rat pheochromocytoma cell line. This model demonstrated estrogenic regulation of neurite outgrowth, spine formation, and gap junction formation. Similarly, an in vitro model for the effects of androgen on neurons is now described. Wild-type cells (PC12-WT) were stably transfected with an expression vector coding for the full-length cDNA for the human androgen receptor (AR). Resultant clones were isolated, screened for incorporation of vector and expression of AR mRNA and protein, and analyzed for morphologic responses to androgen. PC12-WT, NE09 (ER-negative, AR-negative), SER8 (ER-positive, AR-negative), and AR8 (ER-negative, AR-positive) cells were exposed to 10 ng/ml nerve growth factor (NGF), along with 0-10(-7) M dihydrotestosterone (DHT) for 2 days. AR8 cells demonstrated an androgen dose-dependent increase in mean neurite length, branch order, and neurite field area, whereas neurite branch segment length and soma area were not affected by androgen. PC12-WT, NE09, and SER8 cells exhibited no alterations in cell morphology with DHT exposure. Because of the synergistic effects of DHT and NGF, the regulation of NGF receptor mRNA by DHT was evaluated; however, no significant induction of either trkA or p75 mRNA expression by androgen was documented. The results suggest that in AR-positive PC12 cells, androgen acts additively with NGF to increase neurite outgrowth; but androgen effects are mediated specifically through branching and arborization. These responses are similar to developmental studies of androgen effects in vivo. Thus, androgen appears to induce an inherent neural morphologic program in AR-containing cells, which increases the receptive field of these cells, increasing the likelihood for interneural communication, although not promoting communication itself. These cell lines will provide a unique in vitro system for studying mechanisms of androgen-neuron interactions.
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Affiliation(s)
- R H Lustig
- Department of Pediatrics, University of Wisconsin, Madison 53792
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Abstract
In electrical impedance tomography (EIT), current patterns are injected into a subject and boundary voltages are measured to reconstruct a cross-sectional image of resistivity distribution. Static EIT image reconstruction requires a computer model of a subject, an efficient data-collection method and robust and fast reconstruction algorithms. The finite-element method is used as the computer model. The paper describes the finite-element analysis software package developed, including an interactive graphical mesh generator and fast algorithms for solving linear systems of equations using sparse-matrix and vector techniques. Various models of irregularly shaped subjects are developed using mesh-design tools, including automatic mesh generation and optimisation using the Delaunay algorithm. Even though the software package is customised for use in electrical impedance tomography, it can be used for other biomedical research areas, such as impedance cardiography, cardiac defibrillation and impedance pneumography.
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Affiliation(s)
- E J Woo
- Department of Biomedical Engineering, College of Medicine, Kon Kuk University, Choongbuk, Korea
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36
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Lustig RH, Hua P, Yu W, Ahmad FJ, Baas PW. An in vitro model for the effects of estrogen on neurons employing estrogen receptor-transfected PC12 cells. J Neurosci 1994; 14:3945-57. [PMID: 8207498 PMCID: PMC6576956] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Estrogen alters neurite outgrowth, neuritic spine development, and synaptogenesis in estrogen-responsive areas of the rat brain. However, examination of the specific effects of estrogen on neurons in vivo has been difficult. An in vitro model for the effects of estrogen on neurons was developed, using the PC12 rat pheochromocytoma cell line. Wild-type cells (PC12-WT) were stably transfected either with an expression vector coding for the full-length cDNA for the human estrogen receptor (hER), or with a control vector. Resultant clones were isolated, screened for incorporation of vector and expression of ER mRNA and protein, and analyzed for morphologic responses to estrogen. PC12-WT, NEO9 (ER-negative), and SER8 (ER-positive) cells exposed to 100 ng/ml NGF exhibited dose-responsive neurite outgrowth within 2 d by light microscopy (LM). Coadministration of 10(-10) to 10(-9) M estradiol (E2) had minimal effects on neurite outgrowth, neuritic spine development, or interneuritic connections in NEO9 or PC12-WT cells, but in SER8 cells E2 led to additive and dose-dependent increases in neurite outgrowth, spine development, and interneuritic connectivity. Coincubation of SER8 cells with E2 and the antiestrogen ICI 164,384 negated estrogenic effects on spine development and interneuritic connectivity. At the electron microscopic (EM) level, intercellular abutments of NEO9 or PC12-WT cells contained few and rudimentary gap junctions, with no increase by E2. However, SER8 cells exhibited augmented basal frequencies of gap junctions that increased with E2 incubation. Microinjection of Lucifer yellow into PC12-WT and NEO9 cells demonstrated low frequencies of dye coupling and no change with E2, but SER8 cells demonstrated increased dye-coupling frequency with E2 coincubation. The results suggest that SER8 cells recapitulate estrogen effects on neurons in vivo. Estrogen appears to induce an inherent neural morphologic program in estrogen receptor (ER)-containing cells. These three cell lines provide a unique in vitro system for studying mechanisms of estrogen-neuron interactions.
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Affiliation(s)
- R H Lustig
- Department of Pediatrics, University of Wisconsin, Madison 53792
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Zenger M, Brenner M, Hua P, Haruno M, Wilson AF. Measuring oxygen uptake and carbon dioxide production in critically ill patients using a standard blood gas analyzer. Crit Care Med 1994; 22:783-8. [PMID: 8181286 DOI: 10.1097/00003246-199405000-00012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [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: 01/29/2023]
Abstract
OBJECTIVE The measurement of oxygen uptake and CO2 production in critically ill patients requires invasive monitoring or complex analysis equipment. This study investigates the hypothesis that oxygen uptake and CO2 production can be accurately determined by measuring oxygen and CO2 concentrations in samples from inspiratory and expiratory ventilator circuitry, using a standard blood gas analyzer. DESIGN Prospective comparison of CO2 production and oxygen uptake measurements determined by use of a blood gas analyzer vs. a mass spectrometer. SETTING University teaching hospital medical and surgical intensive care units (ICUs). PATIENTS Critically ill patients (n = 46) receiving mechanical ventilation in the ICUs. INTERVENTIONS PO2 and PCO2 were obtained with two new techniques and compared simultaneously with measurements on a mass spectrometer in critically ill, mechanically ventilated patients. Two methods were evaluated: a) arterial blood gas analyzer measurements of PO2 and PCO2 from fluid collected in traps on the inspiratory and expiratory limbs of the ventilator circuitry; b) PO2 and PCO2 measurements of inspiratory and expiratory gas samples collected in bags and injected directly into an arterial blood gas analyzer. Oxygen consumption and CO2 production were compared, using both methods of gas measurements. MEASUREMENTS AND MAIN RESULTS Direct injection of gas samples collected in a bag from inspiratory and expiratory limbs of a breathing circuit into the arterial blood gas analyzer correlated very closely with mass spectrometer measurements for all variables (n = 32 sample measurements in 25 patients): fractional oxygen (r2 = .99, slope = 1.02, bias = 0.37%, precision = 0.54), fractional expired CO2 (r2 = .90, slope = 0.86, bias = -0.10%, precision = 0.15), oxygen uptake (r2 = .87, slope = 0.99, bias = 21.6 mL/min, precision = 38.0), and CO2 production (r2 = .98, slope = 0.95, bias = 7.90 mL/min, precision = 15.3). In contrast, although fractional oxygen and CO2 concentrations were approximated by analysis of fluid collected from inspiratory and expiratory traps, the values did not correlate well enough with mass spectrometer values to yield reasonable oxygen uptake or CO2 production results. CONCLUSION We have demonstrated that direct Fick oxygen uptake and CO2 production can be accurately determined in mechanically ventilated patients, using direct injection of collected gas samples into standard blood gas analyzers. This simple, inexpensive technique can be performed using equipment readily available in any hospital.
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Affiliation(s)
- M Zenger
- Department of Medicine, University of California Irvine Medical Center, Orange 92668
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Archambault JL, Russell PS, Barcelos S, Hua P, Reekie L. Grating-frustrated coupler: a novel channel-dropping filter in single-mode optical fiber. Opt Lett 1994; 19:180. [PMID: 19829584 DOI: 10.1364/ol.19.000180] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Lustig RH, Hua P, Wilson MC, Federoff HJ. Ontogeny, sex dimorphism, and neonatal sex hormone determination of synapse-associated messenger RNAs in rat brain. Brain Res Mol Brain Res 1993; 20:101-10. [PMID: 8255171 DOI: 10.1016/0169-328x(93)90114-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Sex hormones influence neurite outgrowth and synaptogenesis in certain hormone-dependent areas of the rat brain during neonatal development. These alterations are thought to mediate changes in brain structure and function between the sexes. Growth-associated protein 43 kDa (GAP-43) gene expression is estrogen-regulated in the adult ventromedial hypothalamus (VMH) and sexually dimorphic (M:F = 1.8:1) in adult cortex (CTX). Such effects intimate hormonal regulation of synaptic plasticity. To investigate the nature of these dimorphisms, the present study examined the ontogeny of expression of mRNAs encoding 3 neural-specific proteins: GAP-43, SCG10, and synaptosomal-associated protein 25 kDa (SNAP-25); and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), in the VMH and CTX; and also the effects of altering the neonatal sex hormonal milieu on the development of these adult dimorphisms. Levels of specific mRNAs in VMH and CTX were quantitated by slot-blot hybridization in rats of both sexes at different postnatal ages. To determine the involvement of neonatal sex hormones on the levels of these mRNAs, male neonatal rat pups were treated with an estrogen receptor antagonist or an aromatase inhibitor, and neonatal female pups were treated with testosterone or estrogen prior to slot-blot evaluations in adulthood. In VMH, GAP-43 mRNA levels were high on days P1 and P4 with a 3-fold decrease by day P23; in CTX, GAP-43 mRNA first increased by day P11, then fell to baseline by day P23. In VMH, SCG10 mRNA showed only small increases with time; but in CTX, there was a 5-fold drop from days P4 to P23. In VMH, SNAP-25 mRNA was low and changed only slightly; but in CTX there was a 5-fold increase between days P4 and P60. At birth, there was no sex dimorphism in either VMH or CTX, but the levels of all 3 neural-specific mRNAs were sexually dimorphic in adult CTX (M:F = 1.76 for GAP-43, 1.46 for SCG10, 1.44 for SNAP-25). GAPDH mRNA levels were regulated developmentally in VMH and CTX, but there was no sex dimorphism in either area. In male rats who received either an estrogen antagonist or aromatase inhibitor at birth, the CTX GAP-43 and SNAP-25 mRNA levels fell by 30%, to levels similar to untreated females. Conversely, in female rats, neonatal treatment with either testosterone or estrogen increased GAP-43 and SNAP-25 mRNA levels by about 30%, to levels similar to the untreated adult male. SCG10 levels did not demonstrate neonatal hormonal dependence.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- R H Lustig
- Department of Pediatrics, University of Wisconsin, Madison 53792
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Hua P, Woo EJ, Webster JG, Tompkins WJ. Finite element modeling of electrode-skin contact impedance in electrical impedance tomography. IEEE Trans Biomed Eng 1993; 40:335-43. [PMID: 8375870 DOI: 10.1109/10.222326] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.4] [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: 01/30/2023]
Abstract
In electrical impedance tomography (EIT), we inject currents through and measure voltages from an array of surface electrodes. The measured voltages are sensitive to electrode-skin contact impedance because the contact impedance and the current density through this contact impedance are both high. We used large electrodes to provide a more uniform current distribution and reduce the contact impedance. A large electrode differs from a point electrode in that it has shunting and edge effects which cannot be modeled by a single resistor. We used the finite element method (FEM) to study the electric field distributions underneath an electrode, and developed three models: a FEM model, a simplified FEM model and a weighted load model. We showed that the FEM models considered both shunting and edge effects and matched closely the experimental measurements. FEM models for electrodes can be used to improve the performance of an electrical impedance tomography reconstruction algorithm.
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Affiliation(s)
- P Hua
- Applied Research Group, Siemens Gammasonics Inc., Hoffman Estates, IL 60195
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Abstract
In electrical impedance tomography, we inject currents and measure voltages to estimate an object's resistivity distribution. The electrode configuration affects measured voltage data because the electrode-skin contact impedance is high and varies with electrode location. We developed a compound electrode which is composed of two electrodes: a large outer electrode to inject current and a small inner electrode to sense voltage. We used these compound electrodes to measure voltages from a physical phantom. We showed that the measured voltages from the compound electrodes are smaller in amplitude than those from conventional electrodes. This demonstrates that the compound electrode can minimize contact impedance voltage drop from the measured data. We used a finite element model for the compound electrode and incorporated the model into the regularized Newton-Raphson reconstruction algorithm. We performed a sensitivity study and showed that the reconstructed resistivity distributions are less dependent on the unknown contact resistance values for a compound electrode than a conventional electrode and that the use of a compound electrode results in improved images for the reconstruction algorithm.
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Affiliation(s)
- P Hua
- Applied Research Group, Siemens Gammasonics Inc., IL 60195
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Woo EJ, Hua P, Webster JG, Tompkins WJ. A robust image reconstruction algorithm and its parallel implementation in electrical impedance tomography. IEEE Trans Med Imaging 1993; 12:137-146. [PMID: 18218401 DOI: 10.1109/42.232242] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
An efficient and robust image reconstruction algorithm for static impedance imaging using Hachtel's augmented matrix method was developed. This improved Newton-Raphson method produced more accurate images by reducing the undesirable effects of the ill-conditioned Hessian matrix. It is demonstrated that the electrical impedance tomography (EIT) system could produce two-dimensional static images from a physical phantom with 7% spatial resolution at the center and 5% at the periphery. Static EIT image reconstruction requires a large amount of computation. In order to overcome the limitations on reducing the computation time by algorithmic approaches, the improved Newton-Raphson algorithm was implemented on a parallel computer system. It is shown that the parallel computation could reduce the computation time from hours to minutes.
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Affiliation(s)
- E J Woo
- Dept. of Biomed. Eng., Kon Kuk Univ., Choongbuk
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Abstract
We propose the use of electrical impedance tomography (EIT) imaging techniques in the measurement of lung resistivity for detection and monitoring of apnea and edema. In EIT, we inject currents into a subject using multiple electrodes and measure boundary voltages to reconstruct a cross-sectional image of internal resistivity distribution. We found that a simplified, therefore fast, version of the impedance imaging method can be used for detection and monitoring of apnea and edema. We have showed the feasibility of this method through computer simulations and human experiments. We speculate that the EIT imaging technique will be more reliable than the current impedance apnea monitoring method, since we are monitoring the change of internal lung resistivity. However, more study is required to verify that this method performs better in the presence of motion artifact than the conventional two-electrode impedance apnea monitoring method. Future work should include experiments which carefully simulate different kinds of motion artifacts.
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Affiliation(s)
- E J Woo
- Department of Electrical and Computer Engineering, University of Wisconsin, Madison 53706
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Abstract
We have studied the effect of the electrode configuration on the measurement of body impedance and found that the electrode configuration greatly affects the impedance measurement using the four-electrode method. We studied the characteristics of the compound electrode and found that the compound electrode provides the four-electrode method in a compact form. A new method of measuring the skin impedance using simple electrodes at low frequencies was developed. At high frequencies where the effect of internal tissue impedance is not negligible, we used the compensation method using compound electrodes, because they measure the voltage right under the skin. At 50 kHz, we measured the real part of the skin impedance of less than 80 omega on the thorax. We propose a simple instrument which can measure accurate skin impedance at various frequencies.
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Affiliation(s)
- E J Woo
- Department of Biomedical Engineering, College of Medicine, Kon Kuk University, Choongbuk, Republic of Korea
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Hua P, Woo EJ, Webster JG, Tompkins WJ. Improved methods to determine optimal currents in electrical impedance tomography. IEEE Trans Med Imaging 1992; 11:488-495. [PMID: 18222890 DOI: 10.1109/42.192684] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
An electrical impedance tomography (EIT) system that uses the optimal current method to inject currents and the regularized Newton-Raphson algorithm to reconstruct an image of resistivity distribution is discussed. Iterative methods to derive the optimal current patterns through iterative physical measurements are developed. Direct methods to first determine the resistance matrix of a resistivity distribution through a set of current bases is injected and the measured voltage responses are stored. This permits iterative reconstruction techniques to operate on the stored data without requiring lengthy data taking from the object and reduces the effects of motion artifacts. The direct methods have superior performance as compared to the iterative methods in both optimal current and voltage generation. The results obtained with three sets of current bases are studied.
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Affiliation(s)
- P Hua
- Dept. of Electr. & Comput. Eng., Wisconsin Univ., Madison, WI
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Woo EJ, Hua P, Webster JG, Tompkins WJ, Pallas-Areny R. Walsh function current patterns and data synthesis for electrical impedance tomography. IEEE Trans Med Imaging 1992; 11:554-559. [PMID: 18222897 DOI: 10.1109/42.192691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A data collection method which uses Walsh functions as injection current patterns is presented. This method can satisfy two conditions: the optimality of current patterns in every iteration and the single-time data measurement condition. The use of Walsh functions simplifies the design of current sources since only two levels of current (+1 and -1) are required, whereas sinusoidal injection requires a digital-to-analog converter to produce many different values of currents. Compared to diagonal or neighboring type of pulses as injection current patterns, Walsh injection current patterns provide more information about the interior of the subject since Walsh function simulate low and high spatial frequency patterns. Therefore, Walsh function injection uses the simplicity of pulse type injection and yields the better distinguishability or SNR of sinusoidal injection.
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Affiliation(s)
- E J Woo
- Dept. of Biomed. Eng., Kon Kuk Univ., Choongbuk
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Hua P, Woo EJ, Webster JG, Tompkins WJ. Iterative reconstruction methods using regularization and optimal current patterns in electrical impedance tomography. IEEE Trans Med Imaging 1991; 10:621-628. [PMID: 18222869 DOI: 10.1109/42.108598] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
An iterative reconstruction method which minimizes the effects of ill-conditioning is discussed. Based on the modified Newton-Raphson algorithm, a regularization method which integrates prior information into the image reconstruction was developed. This improves the conditioning of the information matrix in the modified Newton-Raphson algorithm. Optimal current patterns were used to obtain voltages with maximal signal-to-noise ratio (SNR). A complete finite element model (FEM) was used for both the internal and the boundary electric fields. Reconstructed images from phantom data show that the use of regularization optimal current patterns, and a complete FEM model improves image accuracy. The authors also investigated factors affecting the image quality of the iterative algorithm such as the initial guess, image iteration, and optimal current updating.
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Affiliation(s)
- P Hua
- Siemens Gammasonics Inc., Hoffman Estates, IL
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Affiliation(s)
- J H Nuske
- Inst. f. Biologie II, RWTH Aachen, FRG
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Abstract
The Newton-Raphson algorithm is an effective reconstruction method. However, it exhibits degraded performance for ill-conditioned problems, especially in the presence of measurement error. This paper uses the regularisation method to improve the system's conditioning, which stabilises the reconstruction method. It shows that the [[ p'' ]] penalty form yields superior images, as compared to the [[ p ]] penalty form.
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Affiliation(s)
- P Hua
- Department of Electrical and Computer Engineering, University of Wisconsin 53706
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Abstract
Recent progress in electrical impedance tomography in North America is reviewed. It emphasises recent progress on the hardware system, measurement method, and reconstruction algorithm. It also describes two new EIT applications.
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Affiliation(s)
- J G Webster
- Department of Electrical and Computer Engineering, University of Wisconsin-Madison 53706
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