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Search Publications by: Carl G. Simon, Jr., Ph.D. (Fed)

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Displaying 26 - 50 of 132

Roles of Nanofiber Scaffold Structure and Chemistry in Directing Human Bone Marrow Stromal Cell Response

August 22, 2016
Author(s)
Sumona Sarkar, Bryan A. Baker, Desu Chen, Patrick S. Pine, Jennifer H. McDaniel, Marc L. Salit, Wolfgang Losert, Carl G. Simon Jr., Joy P. Dunkers
Nanofiber technology has emerged as a promising tool to recapitulate the native extracellular matrix structure; however the properties of nanofibers governing cell-material interactions are still largely undetermined. In this study we have systematically

Machine Learning Strategy to Determine Cell Shape Phenotypes Associated with Micro-Environmental Cues

June 25, 2016
Author(s)
Desu Chen, Sumona Sarkar, Julian Candia, Carl G. Simon Jr., Wolfgang Losert, Joy P. Dunkers, Stephen J. Florczyk, Subhadip Bodhak, Meghan Driscoll
Cell morphology has been identified as a potential indicator of stem cell response and function in biomaterial environments. However, determination of cell shape phenotype in biomaterials is complicated by heterogeneous cell populations, heterogeneous

Strategies for Achieving Measurement Assurance for Cell Therapy Products

June 1, 2016
Author(s)
Carl G. Simon Jr., Anne L. Plant, Sumona Sarkar, John T. Elliott, Sheng Lin-Gibson
Cell therapy products (CTPs) need quantitative, validated, and robust assays to support informed decision making during their development, manufacturing, and regulation. These products, the materials involved in their production and the methods for

3D Segmentation of Stem Cells from Thousands of Confocal Microscopy Images

March 1, 2016
Author(s)
Peter Bajcsy, Mylene H. Simon, Stephen J. Florczyk, Carl G. Simon Jr., Derek Juba, Mary C. Brady
We address the problem of estimating 3D segmentation performance when segmentation is applied to thousands of confocal microscopy images (z-stacks) of cells. With a very large number of z-stacks, manual inputs to validate each segmentation result are

Survey Statistics of Automated Segmentations Applied to Optical Imaging of Mammalian Cells

January 8, 2016
Author(s)
Peter Bajcsy, Antonio Cardone, Joe Chalfoun, Michael W. Halter, Derek Juba, Marcin Kociolek, Michael P. Majurski, Adele P. Peskin, Carl G. Simon Jr., Mylene H. Simon, Antoine Vandecreme, Anne L. Plant, Mary C. Brady
The goal of this survey paper is to overview cellular measurements using optical microscopy imaging followed by automated image segmentation. The cellular measurements of primary interest are taken from mammalian cells and their components. They are

ASTM Workshop on Standards & Measurements for Tissue Engineering Scaffolds

January 1, 2016
Author(s)
Carl G. Simon Jr., John Test, Michael Yaszemski, Reto Luginbuehl, Anthony Ratcliffe, Paul Tomlins
A “Workshop on Standards & Measurements for Tissue Engineering Scaffolds” was held on May 21, 2013 and was sponsored by the American Society of Testing and Materials International (ASTM International) in Indianapolis, IN. The purpose of the workshop was to

Validated Open Source Nanofiber Diameter Measurement Tool

April 30, 2015
Author(s)
Nathan A. Hotaling, Kapil Bharti, Haydn Kriel, Carl G. Simon Jr.
Despite the growing use of nanofiber scaffolds for tissue engineering applications, there is not a validated, readily available (commercial or open source) solution for rapid, automated analysis of nanofiber diameter from scanning electron microscope (SEM)

Ontology Analysis if Global Gene Expression Differences of Human Bone Marrow Stromal Cells Cultured on 3D Scaffolds or 2D Films

July 31, 2014
Author(s)
Bryan A. Baker, Patrick S. Pine, Kaushik Chatterjee, Girish Kumar, Jennifer H. McDaniel, Marc L. Salit, Carl G. Simon Jr.
Differences in gene expression of human bone marrow stromal cells (hBMSCs) during culture in three-dimensional (3D) nanofiber scaffolds or on two-dimensional (2D) films were investigated via pathway analysis of microarray mRNA expression profiles. Previous

Combinatorial Cassette for Screening of Osteogenesis by Transplanted Human Bone Marrow Stromal Cells

April 19, 2014
Author(s)
Subhadip Bodhak, Sheng Lin-Gibson, Carl G. Simon Jr., Luis Fernandez de Castro Diaz, Pamela G. Robey, Sergei A. Kuznetsov, Tina Kilts, Marian F. Young
The use of in vivo transplantation assays under defined experimental conditions has become a valuable standard for evaluating osteogenic potential of different stem cell populations and is the subject of ongoing pre-clinical reconstructive therapy research

Evaluation of the effect of donor variability on stem cell response to biomaterials

April 19, 2014
Author(s)
Stephen J. Florczyk, Bryan A. Baker, Sumona Sarkar, Jennifer H. McDaniel, Patrick S. Pine, Marc L. Salit, Carl G. Simon Jr.
Previous research from our group indicated that nanofiber scaffolds promoted osteogenic differentiation of human bone marrow stromal cells (hBMSC) and similar gene expression to osteogenic supplement (OS) induced osteogenic differentiation [1]. Biological

Machine Learning Analysis for Identification of Cell Shape Metrics Associated with Stem Cell Differentiation in Nanofiber Scaffolds

April 19, 2014
Author(s)
Desu Chen, Sumona Sarkar, Stephen J. Florczyk, Subhadip Bodhak, Carl G. Simon Jr., Joy P. Dunkers, Julian Candia, Wolfgang Losert
Cell shape has been demonstrated to be closely related to cell function and may be an important predictor of cell fate. Many metrics are available to describe cell shape, however the relationship of these metrics to cell fate are not well understood

Measuring Organelle Shape in 3D in Stem Cells Cultured on Nanofiber Scaffolds

April 19, 2014
Author(s)
Carl G. Simon Jr., Peter Bajcsy, Wojtek J. Tutak, Jyotsnendu J. Giri
Previous work has demonstrated that culture of osteoprogenitor cells on nanofiber scaffolds can potentiate osteogenic differentiation [1-4]. Culture of cells in nanofiber scaffolds causes changes to cell morphology, suggesting that morphological changes

Measuring Stem Cell Dimensionality in Tissue Scaffolds

April 1, 2014
Author(s)
Carl G. Simon Jr., Sapun Parekh, Christopher K. Tison, Girish Kumar, Tanya M. Farooque, Charles H. Camp
Many 3D scaffold systems have evolved for tissue engineering, drug screening and in vitro tissue models. However, it is not clear which scaffolds provide a 3D cell niche and there is no clear way to measure cell niche dimensionality. Advances in 3D niche

Airbrushed Nanofiber Scaffolds Support Bone Marrow Stromal Cell Differentiation

November 1, 2013
Author(s)
Carl G. Simon Jr., Wojtek J. Tutak, Sumona Sarkar, Tanya M. Farooque, Jyotsnendu J. Giri, Dongbo Wang, Sheng Lin-Gibson, Joachim Kohn, Durgadas Bolikal
Nanofiber scaffolds are effective for tissue engineering since they emulate the fibrous nanostructure of native extracellular matrix (ECM). Although electrospinning has been the most common approach for fabricating nanofiber scaffolds, airbrushing

Parallel Geometric Classification of Stem Cells by Their 3D Morphology

July 1, 2013
Author(s)
Derek Juba, Antonio Cardone, Cheuk Y. Ip, Carl Simon Jr., Christopher K. Tison, Girish Kumar, Mary C. Brady
Autologous stem cells show great promise for tissue engineering as they can regenerate diseased or damaged tissue, without requiring an organ donor or causing immune rejection. A primary goal of regenerative medicine is to identify methods for controlling

Effect of Surface Chemistry on Stem Cell Response in 2-D vs. 3-D Cell Culture Niches

April 19, 2013
Author(s)
Sumona Sarkar, Carl G. Simon Jr., Roberta I. Lock, Joy P. Dunkers
To develop tissue engineered devices for regenerative medicine strategies, key scaffold properties for directing stem cell response must be identified. As focus shifts from 2-D to 3-D culture systems in an attempt to better recapitulate the natural

Gradient Nanofiber Scaffold Libraries for Screening Cell Response to Poly(e-caprolactone)-Calcium Phosphate Composites

March 1, 2013
Author(s)
Carl G. Simon Jr., Limin Sun, Laurence C. Chow, William Miles, Christopher K. Tison, Kaushik Chatterjee, Marian F. Young, Vinoy Thomas, Murugan Ramalingam
A 2-spinnerette approach has been developed for fabricating nanofiber scaffold gradients for use as 1) scaffold libraries for screening the effect of nanofiber properties on cell response and 2) templates for generating graded tissue interfaces. Although

Optimization of Imaging Polymer Based Scaffolds Using X-Ray Microcomputed Tomography

May 15, 2012
Author(s)
David E. Morris, Melissa L. Mather, Carl Simon Jr., John A. Crowe
The performance of polymer based scaffolds used in regenerative medicine is linked to their structural properties and as such strategies for structural characterization of scaffolds have been developed. X-ray microscopic computed tomography (X-ray micro CT

Gas-Foamed Scaffold Gradients for Combinatorial Screening in 3D

May 1, 2012
Author(s)
Carl G. Simon Jr., Kaushik Chatterjee, Alison M. Kraigsley, Joachim Kohn, Durgadas Bolikal
Current methods for screening cell-material interactions typically utilize two-dimensional (2D) culture format where cells are cultured on flat surfaces. However, there is a need for combinatorial and high-throughput screening methods to systematically