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Displaying 501 - 525 of 1174

Standards in Biothermodynamics

May 15, 2014
Author(s)
Robert N. Goldberg
The field of biothermodynamics encompasses physical property measurements on biochemical and biological systems. This chapter reviews the status of standards documents that are pertinent to biothermodynamics as well as recommendations that have been made

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

Structural Basis for Inactivation of Giardia lamblia Carbamate Kinase by Disulfiram

April 11, 2014
Author(s)
Andrey Galkin, Liudmila Kulakova, Kap Lim, Catherine Chen, Wei Zhang, Illarion Turko, Osnat Herzberg
Carbamate kinase from Giardia lamblia is an essential enzyme for the survival of the organism. The enzyme catalyzes the final step in the arginine dihydrolase pathway converting ADP and carbamoyl phosphate to ATP and carbamate. We previously reported that

AN EXAMINATION OF METAL DEPOSITION DERIVED FROM AEROSPACE-RELATED ACTIVITY IN SEVERAL ENVIRONMENTAL MATRICES COLLECTED FROM WATERS SURROUNDING THE KENNEDY SPACE CENTER (KSC), FLORIDA

April 8, 2014
Author(s)
John Bowden, Theresa M. Cantu, Douglas M. Scheidt, Russell H. Lowers, Brian A. Nocito, Vaneica Y. Young, Louis J. Guillette
Metal deposition originating from anthropogenic activity was examined in a two-tier study using environmental samples collected from several locations at the Kennedy Space Center (KSC) and surrounding Merritt Island National Wildlife Refuge (MINWR) with

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

Application of Falling-Needle Rheometry to Highly Concentrated DNA Solutions.

March 18, 2014
Author(s)
Jessica L. Burger, Hideki Yamamoto, Takamasa Suzuki, Arno D. Laesecke
High concentration DNA solutions are common both in vitro and in vivo, and understanding the rheological properties is a critical area of bioscience. Our previous measurements on high concentration DNA solutions (2-6 mg/ml) interestingly provided evidence

A Novel Mechanism for Regulating the Activity of Proliferating Cell Nuclear Antigen by a Small Protein

March 10, 2014
Author(s)
Zvi Kelman, Richard Y. Huang, Zhuo Li, Jerard Hurwitz, Santangelo J. Thomas, Travis H. Hileman, Yopp C. Daniel, Jeffrey W. Hudgens
Chromosomal DNA replication requires the regulated activity of large number of proteins and complexes. Proliferating cell nuclear antigen (PCNA) protein forms a homotrimeric ring that associates with, and regulates the activity of, many proteins

Certification of Total Arsenic in Blood and Urine Standard Reference Materials by Radiochemical Neutron Activation Analysis and Inductively Coupled Plasma Mass Spectrometry

March 1, 2014
Author(s)
Rick L. Paul, William C. Davis, Karen E. Murphy, Colleen E. Bryan Sallee, Lee L. Yu, William F. Guthrie, Dennis D. Leber, Thomas W. Vetter
A newly developed procedure for determination of arsenic by radiochemical neutron activation analysis was used to measure arsenic in SRM 955c Toxic Elements in Caprine Blood and SRM 2668 Toxic Elements in Frozen Human Urine for the purpose of providing

CPTAC Studies 1 and 5: dissecting variability in multi-site LC-MS/MS proteomics through quality metrics and robust hierarchical multivariate statistics

February 4, 2014
Author(s)
Stephen E. Stein, David M. Bunk, Xia Wang, Matthew Chambers, Lorenzo J. Vega-Montoto, David L. Tabb
Shotgun proteomics experiments integrate a complex sequence of processes, any of which can introduce variability. Quality metrics computed from LC-MS/MS data have relied upon identifying MS/MS scans, but a new mode for the QuaMeter software produces

Influence of tissue, age, and environmental quality on global levels of genomic methylation in the American alligator (Alligator mississippiensis)

January 7, 2014
Author(s)
Benjamin B. Parrott, John Bowden, Satomi Kohno, Jessica A. Cloy-McCoy, Jacqueline T. Bangma, Thomas R. Rainwater, Phillip M. Wilkinson, John Kucklick, Louis J. Guillette
Epigenetic modifications are key mediators of the interactions between the environment and an organism's genome. DNA methylation represents the best-studied epigenetic modification to date and is known to play key roles in regulating transcriptional

Probing the intracellular glutathione redox potential using in-cell NMR spectroscopy

January 2, 2014
Author(s)
Steve Y. Rhieu, Aaron A. Urbas, Daniel W. Bearden, John P. Marino, Vytautas Reipa, Katrice A. Lippa
Non-invasive and real-time analysis of cellular redox processes has been greatly hampered by lack of suitable measurement techniques. Here we describe an in-cell nuclear magnetic resonance (NMR)-based method for measuring the intracellular glutathione

Novel structural features in Candida albicans hyphal glucan provide a basis for differential innate immune recognition of hyphae versus yeast

December 16, 2013
Author(s)
Dan Bearden, Douglas W. Lowman, Rachel R. Greene, Michael D. Kruppa, Max Pottier, Mario Monteiro, David L. Williams
The innate immune system differentially recognizes Candida albicans yeast and hyphae. It is not clear how the innate immune system effectively discriminates between yeast and hyphal forms of C. albicans. Glucans are major components of the fungal cell wall

Quantitative bottom-up proteomics depends on digestion conditions

December 2, 2013
Author(s)
Mark S. Lowenthal, Yuxue Liang, Karen W. Phinney, Stephen E. Stein
Accurate quantification is a fundamental requirement in the fields of proteomics and biomarker discovery, and for clinical diagnostic assays. To demonstrate the extent of quantitative variability in measurable peptide concentrations due to differences

Prototype Phantoms for Characterization of Ultra-Low Field Magnetic Resonance Imaging

November 26, 2013
Author(s)
Michael A. Boss, John A. Mates, Sarah E. Busch, Paul SanGiorgio, Stephen E. Russek, Kai Buckenmaier, Kent D. Irwin, Hsiao-Mei Cho, Gene C. Hilton, John Clarke
Purpose: Prototype phantoms were designed, constructed, and characterized for the purpose of calibrating ultralow field magnetic resonance imaging (ULF MRI) systems. The phantoms were designed to measure spatial resolution and to quantify sensitivity to

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
Displaying 501 - 525 of 1174