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1. DNA methylation age calculators reveal association with diabetic neuropathy in type 1 diabetes

Author

Thomas Donner, P. Rezaeian, John I. Malone, Sharon B. Schwartz, Xiaoyu Gao, Szilard Kiss, Matthew J. Budoff, David R. Sell, A. Dwoskin, Ronald J. Prineas, C. Pittman, M. Reid, C. McDonald, S. Caulder, M. Szpiech, Oscar B. Crofford, Rachel G. Miller, Louis A. Lobes, M. Patronas, C. Canny, M. E. Lackaye, Sandra R. Montezuma, Richard M. Bergenstal, Patricia Gatcomb, Julie A. Stoner, H. Pan, James L. Kinyoun, J. Mortenson, Osama Hamdy, Connie Fountain, David D. Moore, Kusiel Perlman, R. Trail, David A. Lee, J. Sheindlin, Samuel Dagogo-Jack, Jeffrey L. Mahon, Jill P. Crandall, L. Gill, T. Thompson, Lee M. Jampol, K. Koushan, David S. Schade, J. Brown-Friday, M. Basco, S. Dunnigan, J. Bylsma, R. Birk, L. H. Ketai, J. Hotaling, Stephen W. Scherer, W. Mestrezat, Stephan Villavicencio, R. Lyon, M. Carney, John Kramer, Sunder Mudaliar, David M. Nathan, M. Moran, F. Leandre, James W. Albers, L. Survant, Joseph F. Polak, Manjot K. Gill, Anton Orlin, M. Prince, Pamela A. Silver, Amy K. Saenger, John D. Brunzell, Kathleen E. Bainbridge, L. Babbione, Amisha Wallia, J. Vaccaro-Kish, Bradley D. Jones, M. Hebdon, L. McKenzie, Richard M. Hoffman, S. Chang, C. Siebert, George S. Sharuk, D. Counts, A. Lucas, P. Ramos, N. Burkhart, N. Bakshi, N. Flaherty, D. Kenny, M. Driscoll, Harjit Chahal, Ronald K. Mayfield, S. Hensley, E. Weimann, M. Franz, Martin J. Stevens, N. S. Gregory, Christopher J. O'Donnell, J. Laechelt, Pamela Ossorio, Jerry P. Palmer, Rama Natarajan, G. Ziegler, K. Martin, R. Beaser, C. Beck, L. Zhang, T. J. Declue, David M. Kendall, H. Solc, A. Vella, H. Martinez, Cormac T. Taylor, S. Neill, Douglas A. Greene, P. Lee, D. Norman, Andrew J. Barkmeier, Dean P. Hainsworth, Alka Jain, Sapna Gangaputra, N. Thangthaeng, Lorraine Thomas, Michael H. Brent, M. Bracey, Philip Raskin, Q. Clemens, Barbara H. Braffett, Mark S. Mandelcorn, Lloyd Paul Aiello, John E. Godine, T. Speigelberg, R. Chan, R. Hanna, Shelley B. Bull, William I. Sivitz, R. Sussman, C. Kwong, S. Cercone, P. Hollander, N. Leloudes, Joseph M. Terry, J. Wesche, E. A. Tanaka, D. Rosenberg, Wanjie Sun, L. Sun, Tom Clark, Deborah K. Schlossman, Louis M. Luttrell, R. Dunn, A. Farr, K. McVary, Gayle M. Lorenzi, A. Joseph, Catherine C. Cowie, M. Barr, D. Zimbler, S. Mendley, S. Schussler, N. Grove, Matthew D. Davis, Jong Mu Sun, Sophie Rogers, John P. Bantle, Brandy N. Rutledge, Senda Ajroud-Driss, Vincent M. Monnier, Cladd E. Stevens, Y. G. He, M. Phillips, C. Williams, J. MacIndoe, Kaleigh Farrell, Helen Lambeth, Ayad A. Jaffa, J. Quin, Morey W. Haymond, R. Kirby, D. Steinberg, William H. Herman, M. Mech, Arup Das, Robert Detrano, J. Brown, D. McMillan, Linda Snetselaar, Mark W. Johnson, R. Zeitler, T. Taylor, Peter R. Pavan, Michael H. Goldbaum, Bruce A. Perkins, R. G. Campbell, David A. Nicolle, R. J. van der Geest, Irene Hramiak, D. Freking, Lucy A. Levandoski, S. Colson, Charles Campbell, Victoria R. Trapani, Lawrence J. Singerman, D. Meyer, W. Tang, J. Soule, Anita Harrington, Julie A. Nelson, John A. Colwell, Naji Younes, P. Salemi, K. Hansen, Trevor J. Orchard, S. Huddleston, L. Steranchak, C. Sommer, G. Castle, J. Ginsberg, Paula McGee, V. Gama, John Dupre, Z. Strugula, M. Swenson, N. Wong, David A. Bluemke, M. Nutaitis, Anita Agarwal, M. Lin, K. Nickander, Elsayed Z. Soliman, Joao A. Lima, M. L. Schluter, Fred W. Whitehouse, Lisa Diminick, C. Cornish, M. Spencer, Daniel T. Lackland, Ionut Bebu, Hunter Wessells, S. Yacoub-Wasef, A. Determan, L. Van Ottingham, Howard Wolpert, R. Ehrlich, A. Blevins, L. Jovanovic, D. Finegold, Davida F. Kruger, Jye-Yu C. Backlund, K. Chan, Timothy J. Murtha, R. K. Mayfield, Robert W. Cavicchi, Maria F. Lopes-Virella, Thomas A. Weingeist, K. Lee, Mary E. Larkin, B. Blodi, J. Gott, Timothy J. Lyons, J. Selby, Chris Ryan, J. Harth, P. Pugsley, L. Keasler, John D. Maynard, Paul G. Arrigg, Amy B. Karger, P. Colby, J. Farquhar, Mark H. Schutta, Murk-Hein Heinemann, Kathie L. Hermayer, B. Bosco, C. Lovell, A. Bhan, A. Galprin, M. Cayford, M. Schumer, John E. Chapin, D. Rubinstein, F. Miao, V. Asuquo, Catherine L. Martin, Rodney A. Lorenz, Samuel S. Engel, L. Funk, Cyndi F. Liu, Barbara J. Maschak-Carey, Stephen S. Feman, P. Lindsey, M. Giotta, Philip A. Low, S. Kwon, R. Fahlstrom, A. Iannacone, B. French, H. Remtema, L. Cimino, S. Barron, J. McConnell, Jane L. Lynch, L. Kim, T. Williams, A. Degillio, Blanche M. Chavers, M. Novak, Julio V. Santiago, Ronald P. Danis, P. Gaston, Tae Sup Lee, T. Woodfill, R. Cuddihy, Scott M. Steidl, Alanna C. Morrison, E. Ryan, D. Lawrence, D. Cros, T. Adkins, D. Adelman, L. Dews, Patricia A. Cleary, J. Parker, L. Olmos De Koo, C. Kim, Mark R. Palmert, P. Astelford, Stefan Fritz, B. Olson, Kelvin C. Fong, Alan M. Jacobson, Stanley L. Hazen, D. Hornbeck, K. Folino, M. L. Bernal, Gabriel Virella, William V. Tamborlane, Neil H. White, Daniel L. McGee, Denis Daneman, H. Shamoon, William Dahms, S. Elsing, S. Brink, J. Ahern, Delnaz Roshandel, John M. Pach, N. W. Rodger, E. Cupelli, Dara D. Koozekanani, Abbas E. Kitabchi, K. Stoessel, B. Petty, Jamie R. Wood, J. Seegmiller, T. Strand, Y. Li, Eva L. Feldman, Larry Rand, Robert C. Colligan, T. Smith, A. Carlson, David J. Brillon, Margaret L. Bayless, M. Ong, S. Darabian, W. Hsu, Janet E. Olson, B. Rogness, N. Silvers, M. Pfiefer, B. Schaefer, E. Mendelson, S. Braunstein, Maren Nowicki, R. Reed, James S. Floyd, Z. M. Zhang, T. Sandford, R. B. Avery, A. Pratt, Paolo S. Silva, H. Bode, Alexander J. Brucker, Nikhil D. Patel, Alexander R. Lyon, M. Jenner, N. Wimmergren, L. Tuason, J. Rosenzwieg, D. J. Becker, C. Gauthier-Kelly, M. Richardson, Richard S. Crow, Andrew D. Paterson, Mark E. Molitch, Suzanne M. Strowig, S. Pendegast, M. Burger, Ramzi K. Hemady, J. Dingledine, I. H. de Boer, L. Mayer, F. Perdikaris, Om P. Ganda, F. Thoma, Karen J. Cruickshanks, Abraham Thomas, K. Klumpp, Jerry D. Cavallerano, D. Zheng, Annette Barnie, J. L. Canady, C. Wigley, David G. Miller, Sheila Smith-Brewer, D. Ostrowski, P. Crawford, K. Kelly, Robert G. Devenyi, B. Zimmerman, Susan M. Hitt, C. Johnson, L. Gurry, R. Jarboe, E. Angus, David E. Goldstein, A. Killeen, H. Schrott, Orville G. Kolterman, Mark R. Burge, Michael Rubin, J. Lipps Hagan, Alicia J. Jenkins, Hugh D. Wabers, R. Warhol, Edward Chaum, Karen L. Jones, L. Spillers, C. Miao, J. K. Jones, Angelo J. Canty, Rickey E. Carter, Evrim B. Turkbey, B. Burzuk, R. Woodwick, Evica Simjanoski, Michael W. Steffes, S. Crowell, Suresh D. Shah, H. Ricks, J. D. Carey, Paul A. Edwards, S. Holt, W. F. Schwenk, Ronald J. Oudiz, E. Brown, J. Heier, R. L. Ufret-Vincenty, L. M. Aiello, Robert A. Rizza, Karen L. Anderson, Valerie L. Arends, J. Giangiacomo, R. Liss, Aruna V. Sarma, B. Levy, Ellen J. Anderson, S. Catton, P. Callahan, Rodica Pop-Busui, S. Debrabandere, S. Moser, Bernard H. Doft, A. Malayeri, C. Johannes, R. Ramker, J. Rich, M. Fox, Rukhsana G. Mirza, Katherine A. Morgan, Thomas J. Songer, C. Shah, H. Engel, Saul M. Genuth, S. Ferguson, Anushka Patel, C. Haggan, P. Lou, J. Gordon, M. B. Murphy, D. Sandstrom, Dawn M. Ryan, Daniel H. O'Leary, B. Gloeb, Lois E. Schmidt, H. Zegarra, D. Dalton, W. Brown, Tom G. Sheidow, Margaret E. Stockman, Shyam M. Thomas, Charles McKitrick, Jyotika K. Fernandes, P. A. Bourne, L. Baker, G. Friedenberg, Allan Gordon, Allan L. Drash, S. Yoser, D. Wood, S. Johnsonbaugh, A. De Manbey, L. Kaminski, M. May, L. Bestourous, A. Kowarski, M. Geckle, M. Hartmuller, Michael Bryer-Ash, S. List, F. Goetz, V. Reppucci, D. Etzwiler, Rose A. Gubitosi-Klug, M. Brabham, E. Golden, A. Nayate, J. Hu, M. McLellan, Ronald Klein, N. Rude, B. Vittetoe, John M. Lachin, M. Christofi, Zhuo Chen, Isaac Boniuk, C. Strauch, K. Gunyou, L. Delahanty, W. T. Garvey, Andrew P. Boright, Larry D. Hubbard, D. Weiss, Igor Grant, Jonathan Q. Purnell, Jean M. Bucksa, N. Olson, and B. Zinman

Subjects
0301 basic medicine, Adult, Male, medicine.medical_specialty, Diabetic neuropathy, Adolescent, 030209 endocrinology & metabolism, Gastroenterology, Nephropathy, Epigenesis, Genetic, Diabetic complications, 03 medical and health sciences, Young Adult, 0302 clinical medicine, Diabetic Neuropathies, Internal medicine, Diabetes mellitus, Albumins, Genetics, Medicine, Humans, Molecular Biology, Genetics (clinical), Whole blood, Oligonucleotide Array Sequence Analysis, Type 1 diabetes, business.industry, Research, dNaM, DNA methylation age, DNA Methylation, medicine.disease, 030104 developmental biology, Blood pressure, Peripheral neuropathy, Diabetes Mellitus, Type 1, CpG Islands, Female, business, Developmental Biology, Genome-Wide Association Study
Abstract

Background Many CpGs become hyper or hypo-methylated with age. Multiple methods have been developed by Horvath et al. to estimate DNA methylation (DNAm) age including Pan-tissue, Skin & Blood, PhenoAge, and GrimAge. Pan-tissue and Skin & Blood try to estimate chronological age in the normal population whereas PhenoAge and GrimAge use surrogate markers associated with mortality to estimate biological age and its departure from chronological age. Here, we applied Horvath’s four methods to calculate and compare DNAm age in 499 subjects with type 1 diabetes (T1D) from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study using DNAm data measured by Illumina EPIC array in the whole blood. Association of the four DNAm ages with development of diabetic complications including cardiovascular diseases (CVD), nephropathy, retinopathy, and neuropathy, and their risk factors were investigated. Results Pan-tissue and GrimAge were higher whereas Skin & Blood and PhenoAge were lower than chronological age (p < 0.0001). DNAm age was not associated with the risk of CVD or retinopathy over 18–20 years after DNAm measurement. However, higher PhenoAge (β = 0.023, p = 0.007) and GrimAge (β = 0.029, p = 0.002) were associated with higher albumin excretion rate (AER), an indicator of diabetic renal disease, measured over time. GrimAge was also associated with development of both diabetic peripheral neuropathy (OR = 1.07, p = 9.24E−3) and cardiovascular autonomic neuropathy (OR = 1.06, p = 0.011). Both HbA1c (β = 0.38, p = 0.026) and T1D duration (β = 0.01, p = 0.043) were associated with higher PhenoAge. Employment (β = − 1.99, p = 0.045) and leisure time (β = − 0.81, p = 0.022) physical activity were associated with lower Pan-tissue and Skin & Blood, respectively. BMI (β = 0.09, p = 0.048) and current smoking (β = 7.13, p = 9.03E−50) were positively associated with Skin & Blood and GrimAge, respectively. Blood pressure, lipid levels, pulse rate, and alcohol consumption were not associated with DNAm age regardless of the method used. Conclusions Various methods of measuring DNAm age are sub-optimal in detecting people at higher risk of developing diabetic complications although some work better than the others.

Published
2020

2. Laser treatment in fellow eyes with large drusen: updated findings from a pilot randomized clinical trial11The members of the Choroidal Neovascularization Prevention Trial Research Group are listed in the appendix

Author

Michael A. Novak, John H. Niffenegger, Mary Oldroyd, Gregg Greanoff, Robert L. Jack, Sue Solomon, Hong Lei, Maureen G. Maguire, John DuBois, Rajiv Anand, David V. Weinberg, Lee M. Jampol, Eric R. Holz, Beth Chiapetta, Scott D. Pendergast, Serge deBustros, Lisa Hawkins, Marcia Griffin, Jack Cohen, Maureen Hyatt, Don Doherty, David Callanan, Melanie Harris, Timothy W. Olsen, Z. Nicholas Zakov, Abraham Poulose, Rick D. Isernhagen, Justin L. Gottlieb, Hernando Zegarra, Michelle Bartel, Suresh R. Chandra, David A. Saperstein, Connie Fountain, Penny Avery, Ed Heffron, Ray Northway, Daniel F. Martin, Nelson R. Sabates, Ron Schuchard, Frank Meyers, Mark S. Blumenkranz, Kirk H. Packo, William B. Snyder, Diane E. Weiss, Sally Arceneaux, Thomas S. Stevens, Bill Ward, Bob Boleman, James C. Folk, H. Culver Boldt, Jennie Perry, Karen M. Gehrs, Michael W. Neider, Len Richine, Jeanne Van Arsdall, Hunter L. Little, Dwain G. Fuller, Paul Sternberg, Theresa Anderson, Alice T. Lyon, Barbara A Blodi, Kim Tilocco-DuBois, Lawrence J. Singerman, Gabriela Nemes, Jenny Wolfe, Thomas M. Aaberg, Geraldine Daley, Ray Swords, Leslie Cornett, Zuzanna Strugala, David H. Orth, Carolyn Vogel, Stephen R. Russell, Mickie Keeling, Celeste Figliulo, Gene Knutson, William J. Wood, Vicki Crosser, James Gilman, Yvonne Taul, Mary Ilk, Robert Harrison, Susan Lichterman, Cynthia Nork, Felix N. Sabates, Chris Morrison, John W. King, W. Walker, Katherine Lluen-Johnson, Douglas Bryant, Thomas A. Rice, Donna Knight, Camille S. Matta, Hank Aguado, Hugh D. Wabers, Gary Gallimore, Gary E. Fish, Bradley F. Jost, and Edward A. Slade

Subjects
Ophthalmology, medicine.medical_specialty, Randomized controlled trial, law, business.industry, Laser treatment, medicine, Optometry, Drusen, business, medicine.disease, law.invention
Published
2003
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3. Genome-Wide Meta-Analysis of Myopia and Hyperopia Provides Evidence for Replication of 11 Loci

Author

Mario Pirastu, G. E. Munn, L. H. Ketai, K. Taylor, Angela Döring, R. Chan, Jeffrey L. Mahon, Bradley D. Jones, M. Hebdon, Williams L. Dews, Douglas A. Greene, Michael D. Weiss, Sapna Gangaputra, E. A. Tanaka, J. Ginsberg, Ben A. Oostra, Alka Jain, D. Singer, M. Burger, Szilard Kiss, David A. Bluemke, Barbara H. Braffett, Jugnoo S Rahi, L. Sun, C. Clark, Richard M. Bergenstal, Patricia Gatcomb, Paul Mitchell, R. Trail, D. Ryan, Robert Bergren, D. D. Joseph, G. Grand, Blanche M. Chavers, J. M.Verhoeven Virginie, David S. Schade, C. Cowie, Sharon B. Schwartz, G. Ziegler, Lloyd Paul Aiello, Michael H. Brent, John I. Malone, C. Pittman, M. Reid, Stephen S. Feman, Maurizio Fossarello, Kathie L. Hermayer, J. Parker, M. N. Iyer, Hamid Mojibian, Rose Gubitosi-Klug, P. W. Conrad, Daniel T. Lackland, Michael Brändle, C. Canny, Alan F. Wright, M. E. Lackaye, David A. Lee, Rickey E. Carter, J. Brown-Friday, J. K. Jones, J. Distad, A. Thomas, Gordon C. Weir, S. Caulder, M. Szpiech, R. Gstalder, D. Rubinstein, Fred W. Whitehouse, T. Adkins, Gayle M. Lorenzi, L. Survant, Naji Younes, Robert Detrano, Lucy A. Levandoski, Charles Campbell, Lawrence J. Singerman, Johannes R. Vingerling, Joao A.C. Lima, D. Counts, V. Gama, D. M. Nathan, John Dupre, Cornelia M. van Duijn, N. Wong, Anita Harrington, Caroline Hayward, Shelley B. Bull, R. Hackel, William I. Sivitz, Enrico Cagliero, M. Spencer, Albert Hofman, Samuel S. Engel, John E. Hokanson, Julio V. Santiago, David M. Kendall, O. Crofford, T. Thompson, Lee M. Jampol, Kevin Morgan, R. Sussman, James W. Albers, Anita Agarwal, Kevin J. Blinder, Anthony D. Morrison, Nikhil D. Patel, R. Prusak, S. Hitt, Alexander R. Lyon, Saul Genuth, J. Sheindlin, J. Vaccaro-Kish, Goran Benčić, P. Titus, Lisa Diminick, N. Wimmergren, Shelly Olson, Z. Strugula, L. Goings, Lennart C. Karssen, A. Blevins, Harjit Chahal, Ronald K. Mayfield, S. Pendegast, T. J. Lyons, Ozren Polasek, Matthew A. Thomas, Annette Barnie, P. Lindsey, L. Funk, James L. Kinyoun, Neil H. White, L. Mayer, Rodney A. Lorenz, Susan G. Elner, R. L. Pate, E. Simjanoski, R. Beaser, J. Gothrup, Tien Yin Wong, Thomas Bettecken, Jae-Ho Lee, Elsayed Z. Soliman, Ronald P. Danis, Phillippa M. Cumberland, J. Selby, Pamela Rath, H. Martinez, S. Neill, D. Rosenberg, D. Zheng, R. Devenyi, Murk-Hein Heinemann, Albert V. Smith, Alicia J. Jenkins, Rukhsana G. Mirza, Konrad Oexle, Osama Hamdy, John D. Brunzell, Trevor J. Orchard, Daniel Cornfeld, K. Nickander, Igor Rudan, L. Kim, T. Williams, Christopher M. Ryan, William Dahms, P. Paczan Rath, S. Elsing, Matthew J. Budoff, Orville G. Kolterman, Seang-Mei Saw, Lisa A. Prosser, A. Determan, M. Espeland, L. Van Ottingham, B. Petty, A. Farr, Brandy N. Rutledge, Patricia A. Cleary, Margaret L. Bayless, E. Cupelli, Ronald J. Prineas, Jonathan Goldstein, Stefan Fritz, J. Harth, K. Stoessel, Jerry P. Palmer, J. Soule, John A. Colwell, Stephen W. Scherer, Cyndi F. Liu, M. Phillips, Alexander J. Brucker, B. Rogness, Caroline C W Klaver, Joan E. Bailey-Wilson, Claire L. Simpson, Gaurav K. Shah, Louis A. Lobes, S. Mohsen Hosseini, Veronique Vitart, Dwight Stambolian, Mark S. Mandelcorn, John E. Godine, Gabriel Virella, A. Cochrane, David A. Nicolle, Timothy J. Lyons, S. Schussler, Abbas E. Kitabchi, N. Grove, Matthew D. Davis, Andrew K. Vine, Joseph F. Polak, Helen Lambeth, Ayad A. Jaffa, S. Rogers, Samuel Dagogo-Jack, C. Siebert, K. Hansen, H. Shamoon, David J. Brillon, D. Schlossman, H. Ricks, Toby A. Gardner, Mary Frances Cotch, J. Quin, Om P. Ganda, Fernando Rivadeneira, F. Thoma, Brian Fleck, K. Klumpp, Manjot K. Gill, R. J. van der Geest, Hunter Wessells, P. Salemi, P. Gaston, Tae Sup Lee, T. Woodfill, Scott M. Steidl, Thomas Meitinger, Laura Portas, John E. Chapin, Robert Wojciechowski, Martin J. Stevens, Z. M. Zhang, John D. Maynard, Paul G. Arrigg, S. Yacoub-Wasef, Andrew D. Paterson, Barbara J. Maschak-Carey, Ramzi K. Hemady, J. Dingledine, Sheila Smith-Brewer, D. Ostrowski, D. Kenny, Leslie J. Raffel, R. Jarboe, E. Angus, G. Sharuk, Jie Jin Wang, Jye-Yu C. Backlund, K. Chan, R. K. Mayfield, M. Nutaitis, William V. Tamborlane, Emily Y. Chew, Michael H. Goldbaum, S. Kwon, Davida F. Kruger, Mary E. Larkin, Catherine L. Martin, M. Novak, David E. Goldstein, J. Rosenzwieg, D. J. Becker, A. E. Boulton, Jean M. Bucksa, Richard S. Crow, Thomas Donner, Philip A. Low, J. Fradkin, K. Folino, M. L. Bernal, Daniel L. McGee, R. D′Agostino, David G. Miller, Evrim B. Turkbey, Eva L. Feldman, Larry Rand, Harry Campbell, Mark R. Palmert, N. Silvers, M. Driscoll, M. Bracey, Mark E. Molitch, Boniuk Burgess, John P. Bantle, J. D. Carey, Edward Chaum, Philip Raskin, I. H. de Boer, Peter R. Pavan, C. Wigley, Maria F. Lopes-Virella, Pirro G. Hysi, C. Sommer, R. Eastman, B. Schaefer, Maren Nowicki, K. Lee, S. Braunstein, Hugh D. Wabers, A. F. Burrows, M. Johnson, B. Zinman, M. Ong, Samir S. Deeb, C. Gauthier-Kelly, S. Novella, C. Miao, S. Strowig, S. Crowell, Teri A. Manolio, S. Yalamanchi, Christian Gieger, D. Meyer, Louis M. Luttrell, Janie Lipps, William H. Herman, Michael W. Steffes, A. Galprin, A. Iannacone, Federico Murgia, E. Steuer, KyungMann Kim, James F. Wilson, S. Genuth, André G. Uitterlinden, Dean P. Hainsworth, J. Giangiacomo, Wanjie Sun, Aruna V. Sarma, R. Liss, S. Catton, Rodica Pop-Busui, S. Moser, Bernard H. Doft, A. Malayeri, B. Gloeb, W. T. Garvey, Andrew P. Boright, Alan M. Jacobson, Larry D. Hubbard, Barbara E.K. Klein, Shyam M. Thomas, Allan Gordon, Allan L. Drash, S. Yoser, S. Johnsonbaugh, L. Kaminski, G. Meekins, Jonathan Q. Purnell, B. Burzuk, John M. Lachin, M. Geckle, Ronald J. Oudiz, Isaac Boniuk, Xiaohui Li, V. Reppucci, H. Wolpert, D. Etzwiler, M. Brabham, Maria Schache, E. Golden, M. Fox, Jyotika K. Fernandes, Jerome I. Rotter, Paul N. Baird, Michael Bryer-Ash, M. Stern, H. Engel, M. Hawkins, Najaf Amin, C. O′Donnell, M. McLellan, G. Comer, Ronald Klein, D. Sandstrom, H. Zegarra, J. Gordon, M. B. Murphy, P. A. Bourne, L. Baker, Cristina Venturini, D. Wood, H.-Erich Wichmann, M. May, A. Kowarski, Timothy W. Olsen, Thomas J. Songer, Christopher J Hammond, P. Lou, Jill P. Crandall, Miao, Xiaoping, Ophthalmology, Obstetrics & Gynecology, Epidemiology, Clinical Genetics, and Internal Medicine

Subjects
Male, Linkage disequilibrium, Refractive error, genetic structures, Epidemiology, Genome-wide association study, Plant Science, Eye, Linkage Disequilibrium, ASSOCIATION SCANS, MULTIPLE, Medicine and Health Sciences, Myopia, 80 and over, 2.1 Biological and endogenous factors, Aetiology, Age of Onset, FAMILIAL AGGREGATION, Genetics, Aged, 80 and over, Multidisciplinary, AUSTRALIAN SCHOOL-CHILDREN, COMMON VARIANTS, Single Nucleotide, Middle Aged, RETINAL-PIGMENT EPITHELIUM, OUTDOOR ACTIVITY, Hyperopia, Phenotype, Genetic Epidemiology, Medicine, Female, Research Article, Genetic Markers, Adult, General Science & Technology, Science, DCCT/EDIC Research Group, European Continental Ancestry Group, Locus (genetics), Single-nucleotide polymorphism, and over, Biology, Disease Surveillance, Polymorphism, Single Nucleotide, White People, medicine, Genome-Wide Association Studies, Humans, Inherited Eye Disorders, Genetic Predisposition to Disease, Allele, Polymorphism, Eye Disease and Disorders of Vision, Alleles, Genetic Association Studies, Aged, Whites, Human Genome, Biology and Life Sciences, Computational Biology, Human Genetics, Heritability, Plant Pathology, medicine.disease, Genome Analysis, GENE, eye diseases, Ophthalmology, REFRACTIVE ERROR, Genetics of Disease, LINKAGE-DISEQUILIBRIUM, Age of onset
Abstract

Refractive error (RE) is a complex, multifactorial disorder characterized by a mismatch between the optical power of the eye and its axial length that causes object images to be focused off the retina. The two major subtypes of RE are myopia (nearsightedness) and hyperopia (farsightedness), which represent opposite ends of the distribution of the quantitative measure of spherical refraction. We performed a fixed effects meta-analysis of genome-wide association results of myopia and hyperopia from 9 studies of European-derived populations: AREDS, KORA, FES, OGP-Talana, MESA, RSI, RSII, RSIII and ERF. One genome-wide significant region was observed for myopia, corresponding to a previously identified myopia locus on 8q12 (p = 1.25×10-8), which has been reported by Kiefer et al. as significantly associated with myopia age at onset and Verhoeven et al. as significantly associated to mean spherical-equivalent (MSE) refractive error. We observed two genome-wide significant associations with hyperopia. These regions overlapped with loci on 15q14 (minimum p value = 9.11×10-11) and 8q12 (minimum p value 1.82×10-11) previously reported for MSE and myopia age at onset. We also used an intermarker linkage- disequilibrium-based method for calculating the effective number of tests in targeted regional replication analyses. We analyzed myopia (which represents the closest phenotype in our data to the one used by Kiefer et al.) and showed replication of 10 additional loci associated with myopia previously reported by Kiefer et al. This is the first replication of these loci using myopia as the trait under analysis. "Replication-level" association was also seen between hyperopia and 12 of Kiefer et al.'s published loci. For the loci that show evidence of association to both myopia and hyperopia, the estimated effect of the risk alleles were in opposite directions for the two traits. This suggests that these loci are important contributors to variation of refractive error across the distribution.

Published
2014
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4. Functional and Anatomic Consequences of Subretinal Dosing in the Cynomolgus Macaque

Author

Michael W. Neider, Charlene B Y Kim, Brian J Christian, Christopher J. Murphy, Ryan J. McCulloh, Hugh D. Wabers, Carol A. Rasmussen, Paul E. Miller, Richard R. Dubielzig, T Michael Nork, and James N. Ver Hoeve

Subjects
Opsin, medicine.medical_specialty, Rhodopsin, genetic structures, Acetates, Sodium Chloride, Article, Retina, Ophthalmoscopy, Drug Delivery Systems, Macula Lutea, Ophthalmology, Glial Fibrillary Acidic Protein, medicine, Electroretinography, Animals, Minerals, Glial fibrillary acidic protein, biology, medicine.diagnostic_test, Opsins, Fundus photography, Retinal detachment, Anatomy, medicine.disease, Immunohistochemistry, eye diseases, Drug Combinations, Macaca fascicularis, Microscopy, Electron, medicine.anatomical_structure, Intravitreal Injections, biology.protein, sense organs, Tomography, Optical Coherence
Abstract

Objective To characterize functional and anatomic sequelae of a bleb induced by subretinal injection. Methods Subretinal injections (100 μL) of balanced salt solution were placed in the superotemporal macula of 1 eye in 3 cynomolgus macaques. Fellow eyes received intravitreal injections (100 μL) of balanced salt solution. Fundus photography, ocular coherence tomography, and multifocal electroretinography were performed before and immediately after injection and again at intervals up to 3 months postinjection. Histopathologic analyses included transmission electron microscopy and immunohistochemistry for glial fibrillary acidic protein, rhodopsin, M/L-cone opsin, and S-cone opsin. Results Retinas were reattached by 2 days postinjection (seen by ocular coherence tomography). Multifocal electroretinography waveforms were suppressed post–subretinal injection within the subretinal injection bleb and, surprisingly, also in regions far peripheral to this area. Multifocal electroretinography amplitudes were nearly completely recovered by 90 days. The spectral-domain ocular coherence tomography inner segment–outer segment line had decreased reflectivity at 92 days. Glial fibrillary acidic protein and S-cone opsin staining were unaffected. Rhodopsin and M/L-cone opsins were partially displaced into the inner segments. Transmission electron microscopy revealed disorganization of the outer segment rod (but not cone) discs. At all postinjection intervals, eyes with intravitreal injection were similar to baseline. Conclusions Subretinal injection is a promising route for drug delivery to the eye. Three months post–subretinal injection, retinal function was nearly recovered, although reorganization of the outer segment rod disc remained disrupted. Understanding the functional and anatomic effects of subretinal injection is important for interpretation of the effects of compounds delivered to the subretinal space. Clinical Relevance Subretinal injection is a new potential route for drug delivery to the eye. Separating drug effects from the procedural effects is critical.

Published
2011

5. Effect of hard segment chemistry and strain on the stability of polyurethanes: in vivo biostability

Author

Robert W. Hergenrother, Stuart L. Cooper, and Hugh D. Wabers

Subjects
Materials science, Polymers, Scanning electron microscope, Polyurethanes, Biophysics, Bioengineering, Biomaterials, chemistry.chemical_compound, Drug Stability, Ultimate tensile strength, Polymer chemistry, Animals, Methylene, Polyurethane, Tensile testing, chemistry.chemical_classification, Biomaterial, Prostheses and Implants, Polymer, Rats, chemistry, Butanediol, Mechanics of Materials, Microscopy, Electron, Scanning, Ceramics and Composites, Nuclear chemistry
Abstract

We investigated four polyurethanes that were synthesized with different hard segments and four commercial polyurethanes for in vivo biostability. The four polyurethanes with the varying hard segments were based on a 3:2:1 mole ratio of methylene diphenylene diisocyanate (MDI) or methylene dicyclohexane diisocyanate (H 12 MDI), butanediol (BD) or ethylene diamine (ED) and polytetramethylene oxide (PTMO) (MW = 1000). Four commercial polyurethanes were also used: Biomer ® , Pellethane ® , Medtronic experimental C-19 (C-19) and Medtronic experimental C-36 (C-36). Films of the polymers were implanted subcutaneously in rats for up to 12 wk to assess their biostability. Polymer films were implanted either with a 100% strain applied or in the unstrained state. Measurement of tensile properties, molecular weight and surface properties before and after implantation assessed the stability of each of the polymers. Surface cracking was observed with scanning electron microscopy and the extent and depth of cracking were determined. Pellethane ® , C-19 and C-36 showed the least evidence of degradation, although all underwent strain-induced phenomena that decreased their tensile elongation when an external force was applied. After implantation, the BD chain-extended polymers retained their tensile properties better than ED chain-extended polymers. H 12 MDI-based polyurethanes were more susceptible to surface cracking and molecular weight changes than MDI-based polyurethanes, possibly due to the lack of a crystallizable hard segment.

Published
1993
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6. Biostability and blood-contacting properties of sulfonate grafted polyurethane and Biomer

Author

Michael F. Wolf, Ann T. Okkema, Hugh D. Wabers, Robert W. Hergenrother, Stuart L. Cooper, and Timothy J. McCoy

Subjects
chemistry.chemical_classification, Materials science, Ethylene oxide, Biomedical Engineering, Biophysics, Bioengineering, Polymer, Polyethylene, Biodegradation, Biomaterials, chemistry.chemical_compound, Sulfonate, chemistry, Ultimate tensile strength, Polymer chemistry, Ex vivo, Polyurethane, Nuclear chemistry
Abstract

Sulfonate-containing polyurethanes were evaluated for in vivo biodegradation using subcutaneously implanted tensile bars. In addition, these anionically charged polyurethanes were evaluated for in vivo activation of human complement C3a and ex vivo platelet deposition in arteriovenouslyshunted canines. The sulfonate derivatized polymers included laboratory synthesized polyurethane and Biomer. Other polymers used for references included IntramedicTM polyethylene, SilasticTM and a poly(ethylene oxide) based polyurethane. The biodegradation results indicated that Biomer and the laboratory sulfonated Biomer (both manufactured with stabilizers), remained mechanically stable, retaining both tensile strength and elasticity after 4 weeks of subcutaneous implantation. The unstabilized polyurethanes (with or without sulfonation), however, showed marked cracking and a loss of mechanical properties after the same period of subcutaneous implantation. Sulfonated polyurethanes depressed human complement C3a activation i...

Published
1993
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7. The effect of chain extenders and stabilizers on thein-vivo stability of polyurethanes

Author

Stuart L. Cooper, Hugh D. Wabers, and Robert W. Hergenrother

Subjects
Materials science, Antioxidant, In vivo, medicine.medical_treatment, General Engineering, medicine, Organic chemistry, General Medicine, Nuclear chemistry
Abstract

Poly(etherurethane) (PEU) and poly(etherurethaneurea) (Biomer®) films with and without antioxidant stabilizers were subcutaneously implanted into dogs and rats for up to 10 weeks. It was found that the molecular weight of the PEU films decreased over the 10-week period, while the Biomer® films increased in molecular weight. The presence of the stabilizers resulted in less severe changes in molecular weight. Surface cracking was most pronounced on both the stabilized and nonstabilized PEU films. Stress did not have to be applied to induce the surface cracking.

Published
1992
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8. Effect of hydrophilic soft segment side chains on the surface properties and blood compatibility of segmented poly (urethaneureas)

Author

Atsushi Takahara, Stuart L. Cooper, Ann Z. Okkema, and Hugh D. Wabers

Subjects
Blood Platelets, Materials science, Spectrophotometry, Infrared, Polyurethanes, Diol, Biomedical Engineering, Biocompatible Materials, Biomaterials, Contact angle, Structure-Activity Relationship, chemistry.chemical_compound, Dogs, Hydrophily, Polymer chemistry, Copolymer, Side chain, Animals, Cyanates, Polyurethane, chemistry.chemical_classification, Calorimetry, Differential Scanning, Polymer, Blood Physiological Phenomena, Sulfonate, chemistry, Microscopy, Electron, Scanning, Stress, Mechanical, Electron Probe Microanalysis, Isocyanates
Abstract

Segmented poly(urethaneureas) with hydrophilic side chains were prepared from poly(tetramethylene oxide) (PTMO), 4,4'-diphenylmethane diisocyanate (MDI), ethylene diamine (ED) and a diol with a long hydrophilic side chain comprised of an ethylene oxide-proplene oxide copolymer. The end groups of the hydrophilic chains were either sodium sulfonate or methoxy groups. The state of microphase separation showed a small dependence on the fraction of long-chain hydrophilic diol. Surface analysis by means of static underwater contact angle and dynamic contact angle measurements revealed that the graft chains were at the aqueous interface in the hydrated state. An ex vivo A-V shunt experiment revealed that a more thrombogenic blood-material response was correlated with an increase in the concentration of polymeric hydrophilic side chain incorporation. The polyurethane containing a long chain diol with methoxy end groups exhibited a higher level of thrombogenicity than the similar polymers possessing a sulfonate terminated side chain.

Published
1991
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9. Prolonged effect of intensive therapy on the risk of retinopathy complications in patients with type 1 diabetes mellitus: 10 years after the Diabetes Control and Complications Trial

Author

Timothy W. Olsen, S. Hitt, Thomas J. Songer, Alan M. Jacobson, A. Burwood, R. Beaser, M. Szpiech, H. Martinez, Gayle M. Lorenzi, Anthony D. Morrison, C. Hannon, A. Farr, M. Hebdon, R. Colligan, T. Manolio, C. Wilson, Kathie L. Hermayer, John I. Malone, B. Burzuk, Kathy Glander, N. Silvers, B. Jones, A. Galpirn, M. Reid, David E. Goldstein, L. Sun, J. Giangiacom, P. Lou, Dean P. Hainsworth, Shalamar D. Sibley, Ronald J. Prineas, Louis A. Lobes, H. Wolpert, Mark E. Molitch, J. Sheindlin, Senda Ajroud-Driss, L. Dews, Kate Edwards, John M. Pach, Wanjie Sun, E. Cupelli, K. Stoessel, Samuel Dagogo-Jack, K. Harvey, J. Gordon, M. B. Murphy, John P. Bantle, J. D. Carey, Inger Burnett-Zeigler, Andrew M. Paterson, Henry Ferreyra, Manjot K. Gill, Barbara H. Waberski, B. Rogness, Fred W. Whitehouse, R. Ufret, Gordon C. Weir, Daniel H. O'Leary, S. Thomas, Barbara E. K. Klein, G. Ziegler, C. Wigley, L. Kastorff, C. Siebert, M. Palmert, C. Clark, J. Brown-Friday, S. Braunstein, Martin J. Stevens, M. Nutaitis, S. Catton, Samir S. Deeb, William V. Tamborlane, J. Alappatt, Robert Bergren, R. Eastman, Samuel S. Engel, K. Gehres, John M. Lachin, Davida F. Kruger, Jill P. Crandall, P. Geithman, Blanche M. Chavers, Stephen S. Feman, Mary E. Larkin, Thomas C. Lee, Catherine L. Martin, J. Parker, C. West, A. Gordon, Hugh D. Wabers, Sharon B. Schwartz, B. Zinman, M. Espeland, Neil H. White, M. N. Iyer, Rose Gubitosi-Klug, C. Canny, Robert Detrano, S. MacLean, Alice T. Lyon, M. E. Lackaye, Oscar B. Crofford, David A. Lee, M. Brent, Mark S. Mandelcorn, D. Badal, Lucy A. Levandoski, Barbara J. Maschak-Carey, John E. Godine, M. Hawkins, R. Gstalder, L. Survant, Charles Campbell, Matthew D. Davis, Anupam Agarwal, Lawrence J. Singerman, Brandy N. Rutledge, Anita Harrington, M. Novak, David A. Nicolle, P. Gaston, Isaac Boniuk, William H. Herman, S. Park, D. Counts, J. Quin, Nancy L. Robinson, Enrico Cagliero, T. Adkins, T. Woodfill, Scott M. Steidl, John Dupre, P. A. Bourne, L. Baker, D. Sandstrom, K. Miner, L. Mayer, S. Schussler, N. Grove, N. Wong, A. Iannacone, D. Wood, Lisa Diminick, D. Meyer, Barbara Esser, T. Thompson, David M. Nathan, A. Edwards, Lee M. Jampol, David S. Schade, M. Croswell, Joseph F. Polak, M. Spencer, Helen Lambeth, Paul G. Arrigg, Janie Lipps, H. Zegarra, Rodney A. Lorenz, Ayad A. Jaffa, James W. Albers, P. Astlesford, Thomas A. Weingeist, J. Vaccaro-Kish, Alicia J. Jenkins, Ronald K. Mayfield, M. May, A. Kowarski, Michael W. Steffes, W. T. Garvey, Saul Genuth, D. Zheng, Andrew P. Boright, J. Ginsberg, M. L. Bernal, Daniel L. McGee, Eva L. Feldman, Larry Rand, P. Low, J. Rosenzweig, L. Funk, Larry D. Hubbard, Orville G. Kolterman, D. Blackburn, E. Steuer, D. Rosenberg, Rodica Pop-Busui, S. Moser, John E. Hokanson, Julio V. Santiago, Daniel T. Lackland, James L. Kinyoun, Kevin J. Blinder, K. Taylor, D. Hornbeck, C. O'Donnell, Bernard H. Doft, Susan G. Elner, Dean B. Burgess, D. Kenny, Jeffrey M. Joyce, John D. Brunzell, O. Hamdy, Jerry P. Palmer, Jonathan Q. Purnell, R. Zeither, Douglas A. Greene, E. A. Tanaka, Yu-Guang He, Ramzi K. Hemady, Arup Das, Michael Bryer-Ash, Sheila Smith-Brewer, D. Ostrowski, M. Stern, C. Williams, Andrew K. Vine, M. McLellan, Ronald Klein, Annette Barnie, Michael H. Goldbaum, E. Angus, S. Scherer, R. D'Agostino, Philip Raskin, Santica M. Marcovina, B. Schaefer, A. F. Burrows, K. Morgan, David J. Brillon, H. Ricks, S. Strowig, R. Oudiz, S. Yacoub-Wasef, Jye-Yu C. Backlund, K. Chan, B. Gloeb, M. Johnson, Stephen R. Russell, D. J. Becker, Richard S. Crow, J. L. Canady, David G. Miller, O. Stone, Allan L. Drash, S. Yoser, S. Johnsonbaugh, Edward Chaum, L. Kaminski, M. Fox, J. Kramer, M. Bracey, H. Engel, Peter R. Pavan, Maria F. Lopes-Virella, C. Sommer, Daniel P. Joseph, M. Geckle, V. Reppucci, D. Etzwiler, M. Brabham, J. Fradkin, K. Lee, Jean M. Bucksa, E. Golden, Thomas Donner, Edwin M. Stone, Shelley B. Bull, William I. Sivitz, J. Selby, Pamela Rath, Murk-Hein Heinemann, L. Kim, T. Williams, D. Noller, D. Singer, J. Long, G. Grand, R. Devenyi, J. M. Schluter, B. Petty, Margaret L. Bayless, Alexander J. Brucker, S. Fritz, C. Cowie, Om P. Ganda, F. Thoma, K. Klumpp, Z. Strugula, Timothy J. Lyons, Patricia A. Cleary, A. Blevins, H. Shamoon, J. Soule, John A. Colwell, M. Phillips, Gaurav K. Shah, C. Hurtenbach, S. Rogers, Richard M. Bergenstal, Patricia Gatcomb, R. Trail, H. Culver Boldt, J. Bayless, Jonathan Shankle, David M. Kendall, Matthew A. Thomas, P. G. Sharuk, P. Lindsey, Ronald P. Danis, Christopher M. Ryan, William Dahms, P. Paczan Rath, S. Elsing, Gabriel Virella, Abbas E. Kitabchi, D. Moore, S. Pendegras, Trevor J. Orchard, K. Nickander, A. Determan, L. Van Ottingham, J. Harth, Michael W. Neider, and Shelly Olson

Subjects
Adult, Blood Glucose, Male, medicine.medical_specialty, endocrine system diseases, Adolescent, Article, law.invention, chemistry.chemical_compound, Young Adult, Randomized controlled trial, law, Risk Factors, Internal medicine, Diabetes mellitus, medicine, Prevalence, Humans, Hypoglycemic Agents, Insulin, Risk factor, Infusion Pumps, Glycated Hemoglobin, Type 1 diabetes, Diabetic Retinopathy, medicine.diagnostic_test, business.industry, Incidence, Fundus photography, Diabetic retinopathy, medicine.disease, Surgery, Ophthalmology, Diabetes Mellitus, Type 1, chemistry, Disease Progression, Female, Glycated hemoglobin, business, Retinopathy, Follow-Up Studies
Abstract

OBJECTIVE To examine the persistence of the original treatment effects 10 years after the Diabetes Control and Complications Trial (DCCT) in the follow-up Epidemiology of Diabetes Interventions and Complications (EDIC) study. In the DCCT, intensive therapy aimed at near-normal glycemia reduced the risk of microvascular complications of type 1 diabetes mellitus compared with conventional therapy. METHODS Retinopathy was evaluated by fundus photography in 1211 subjects at EDIC year 10. Further 3-step progression on the Early Treatment Diabetic Retinopathy Study scale from DCCT closeout was the primary outcome. RESULTS After 10 years of EDIC follow-up, there was no significant difference in mean glycated hemoglobin levels (8.07% vs 7.98%) between the original treatment groups. Nevertheless, compared with the former conventional treatment group, the former intensive group had significantly lower incidences from DCCT close of further retinopathy progression and proliferative retinopathy or worse (hazard reductions, 53%-56%; P < .001). The risk (hazard) reductions at 10 years of EDIC were attenuated compared with the 70% to 71% over the first 4 years of EDIC (P < .001). The persistent beneficial effects of former intensive therapy were largely explained by the difference in glycated hemoglobin levels during DCCT. CONCLUSION The persistent difference in diabetic retinopathy between former intensive and conventional therapy ("metabolic memory") continues for at least 10 years but may be waning. TRIAL REGISTRATION (clinicaltrials.gov) Identifiers: NCT00360815 and NCT00360893.

Published
2008

10. Thrombus deposition on polyurethanes designed for biomedical applications

Author

A. J. Coury, Hugh D. Wabers, Stuart L. Cooper, and Robert W. Hergenrother

Subjects
Blood Platelets, Materials science, Surface Properties, Polyurethanes, Thrombogenicity, Ether, Contact angle, chemistry.chemical_compound, Dogs, Materials Testing, Acetone, Animals, Composite material, chemistry.chemical_classification, Wax, Spectrum Analysis, Extraction (chemistry), General Engineering, Fibrinogen, Thrombosis, General Medicine, Polymer, chemistry, Chemical engineering, visual_art, visual_art.visual_art_medium, Extrusion
Abstract

Thrombogenicity was assessed by measuring the amount of 111In-platelets and 125I-fibrinogen deposited on the inner luminal surface of six polyurethanes for up to 60 min of blood contact in a canine ex-vivo shunt model. Commercial and laboratory synthesized polymers were examined. Two of the commercially synthesized polyurethanes (Biostable PURs) do not contain ether linkages in the polymer backbone and have previously shown resistance to oxidative and hydrolytic degradation. Static contact angle measurements, dynamic contact angle measurements, and ESCA were used to characterize the surfaces of these polyurethanes. The effectiveness of an acetone extraction used to remove extrusion waxes from Pellethane 2363-80A was similarly studied. Both Pellethane 2363-80A and the ether-free materials had relatively nonthrombogenic surfaces, as indicated by low platelet and fibrinogen deposition, making them potentially good candidates for biomedical applications.

Published
1992

11. Brightness, Contrast, and Color Balance of Digital versus Film Retinal Images in the Age-Related Eye Disease Study 2

Author

Anthony J. Pugliese, Ronald P. Danis, Larry D. Hubbard, James White, Dennis W. Thayer, Hugh D. Wabers, Michael W. Neider, and Michael F. Pugliese

Subjects
Male, Brightness, Light, genetic structures, Channel (digital image), Image quality, media_common.quotation_subject, Color, Color balance, Drusen, Luminance, Retina, Macular Degeneration, Digital image, Photography, medicine, Humans, Contrast (vision), Computer vision, Aged, Mathematics, media_common, Aged, 80 and over, business.industry, Signal Processing, Computer-Assisted, Middle Aged, medicine.disease, Female, sense organs, Artificial intelligence, business
Abstract

PURPOSE To analyze brightness, contrast, and color balance of digital versus film retinal images in a multicenter clinical trial, to propose a model image from exemplars, and to optimize both image types for evaluation of age-related macular degeneration (AMD). METHODS The Age-Related Eye Disease Study 2 (AREDS2) is enrolling subjects from 90 clinics, with three quarters of them using digital and one quarter using film cameras. Image brightness (B), contrast (C), and color balance (CB) were measured with three-color luminance histograms. First, the exemplars (film and digital) from expert groups were analyzed, and an AMD-oriented model was constructed. Second, the impact of B/C/CB on the appearance of typical AMD abnormalities was analyzed. Third, B/C/CB in AREDS2 images were compared between film (156 eyes) and digital (605 eyes), and against the model. Fourth, suboptimal images were enhanced by adjusting B/C/CB to bring them into accord with model parameters. RESULTS Exemplar images had similar brightness, contrast, and color balance, supporting an image model. Varying a specimen image through a wide range of B/C/CB revealed greatest contrast of drusen and pigment abnormalities against normal retinal pigment epithelium with the model parameters. AREDS2 digital images were more variable than film, with lower correspondence to our model. Ten percent of digital were too dim and 19% too bright (oversaturated), versus 1% and 4% of film, respectively. On average, digital had lower green channel contrast (giving less retinal detail) than film. Overly red color balance (weaker green) was observed in 23% of digital versus 8% of film. About half of digital (but fewer film) images required enhancement before AMD grading. After optimization of both image types, AREDS2 image quality was judged as good as that in AREDS (all film). CONCLUSIONS A histogram-based model, derived from exemplars, provides a pragmatic guide for image analysis and enhancement. In AREDS2, the best digital images matched the best film. Overall, however, digital provided lower contrast of retinal detail. Digital images taken with higher G-to-R ratio showed better brightness and contrast management. Optimization of images in the multicenter study helps standardize documentation of AMD (ClinicalTrials.gov NCT00345176).

Published
2008
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12. Series shunt evaluation of polyurethane vascular graft materials in chronically AV-shunted canines

Author

Stuart L. Cooper, Timothy J. McCoy, and Hugh D. Wabers

Subjects
Blood Platelets, Materials science, Biocompatibility, Platelet Aggregation, Cell Survival, Polyurethanes, Biomedical Engineering, Silicones, Biocompatible Materials, Iliac Vein, Iliac Artery, Biomaterials, chemistry.chemical_compound, Arteriovenous Shunt, Surgical, Dogs, Animals, Platelet, Dimethylpolysiloxanes, Polyurethane, biology, Platelet Count, Fissipedia, Biomaterial, biology.organism_classification, Blood Vessel Prosthesis, chemistry, Microscopy, Electron, Scanning, Polyethylenes, Vascular graft, Ex vivo, Shunt (electrical), Biomedical engineering
Abstract

Well characterized, laboratory-synthesized polymeric materials which have been extensively tested for biocompatibility via initial platelet and protein deposition in an acute ex vivo canine model were placed as interpositional series shunts in canines with chronically implanted iliac arteriovenous shunts ex vivo. Platelet deposition was measured on a base polyurethane block copolymer, a sulfonated ionic derivative, an alkyl grafted (C18) derivative, Biomer, polyethylene, and polydimethylsiloxane for 24 h using radiolabeled platelets. Platelet survival and in vitro aggregation were determined to investigate the effects of the shunting pprocedure on experimental animals. The viability of adopting a chronic arteriovenous (iliac) shunted canine model for use with series shunts to evaluate polyurethanes having applications as materials in vascular graft construction was investigated and the results compared with acute model data.

Published
1990

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