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Lili Wang, Xin Xiang Wang, Y Li, Min Mo, Yiyuan Yi, Qian Wang, W Gao, Roy A. Mariuzza
Helper T cell activation generally requires the co-receptor CD4, which binds MHC class II molecules. A remarkable feature of the CD4MHC class II interaction is its exceptionally low affinity, which ranges from KD ~200 μM to >2 mM. Investigating the
Wendy R. Altman, John M. Moreland, Stephen E. Russek, Bruce W. Han, Victor M. Bright
Trapping, release, and transport of individual or ensembles of 2.8 υm superparamagnetic beads functionalized with streptavidin were demonstrated using an addressable and non-volatile array of spin-valve (SV) traps integrated into a microfluidic channel
Wendy R. Altman, John M. Moreland, Stephen E. Russek, Victor M. Bright
This work describes a novel microfluidic platform to trap, release, transport, and detect superparamagnetic beads (SPBs) with magnetic spin-valves (SVs). This new technique for simultaneous SPB manipulation and detection was demonstrated on a linear array
Adele P. Peskin, Daniel J. Hoeppner, Christina H. Stuelten
We describe a new technique to segment and track the cell images of a breast cancer cell line in order to study cell migration and metastasis. Within each image cell phenotypes vary widely, ranging from very bright completely bounded cells to barely
Curtis W. Meuse, R W. Hendler, P D. Smith, John Kakareka
New procedures are presented for preparing thin films of bR in a CaF2 cell and maintaining the hydration level between 0.1 and 0.5 μL/cm2, at a pH near 7.1. The same sample and same laser pulse energy were used to accumulate both IR and visible kinetic
We have re-examined the sequential proton-binding and -releasing amino acid side chains involved in the energy-driven transport of protons across the membrane protein bacteriorhodopsin (bR), by using new procedures for obtaining IR absolute spectra for
Marc L. Salit, Lichun Jiang, Felix Schlesinger, Brian Oliver, Carrie Davis, Yu Zhang, Renhua Li, Thomas R. Gingeras
High-throughput sequencing of cDNA (RNA-seq) is a widely deployed transcriptome profiling and annotation technique, but questions about the performance of different protocols and platforms remain. We used a newly developed pool of 96 synthetic RNAs with
Ji Y. Lee, Matthew L. Clarke, Fuyuki Tokumasu, John F. Lesoine, David W. Allen, Robert C. Chang, Maritoni A. Litorja, Jeeseong Hwang
We report a hyperspectral imaging and analysis technique to resolve unique physico-chemical characteristics of subcellular substances in single erythrocytes. We constructed a microscope system installed with a spectral light engine capable of controlling
Proliferating cell nuclear antigen (PCNA) monomers assemble to form a ring-shaped clamp complex that encircles duplex DNA. PCNA binding to other proteins tethers them to the DNA providing contacts and interactions for many other enzymes essential for DNA
Sheldon M. Wiederhorn, Carl G. Simon Jr., Young-Hun Chae
The adhesion of Osteoblast-like cells to silicate and borate glasses was measured using colloidal probe microscopy in a cell growth medium. The probe consisted of silicate and borate glass spheres, 25 µm to 50 µm in diameter, attached to the tip of an
M Miral Dizdar, Pawel Jaruga, Prasad T. Reddy, Bryant C. Nelson, Mark S. Lowenthal
Reduced DNA repair capacity is associated with increased risk for a variety of disease processes including carcinogenesis. Thus, DNA repair proteins have the potential to be used as important predictive, prognostic and therapeutic biomarkers in cancer and
A procedure is described for assigning values of the number of equivalent reference fluorophores (ERF) to microspheres labeled with a fluorophore designed to produce fluorescence in a given channel of a multicolor flow cytometer. There is a different
Lili Wang, Hua-Jun He, Michel Bernier, Rajib K. Paul, Alejandro Martin-Montalvo, Morten Scheibye-Knudsen, Shaoming Song, Sean M. Armour, Vilhelm A. Bohr, Yaping Zong, David A. Sinclair, Rafael de Cabo
In mammals, the transcriptional activity of signal transducer and activator of transcription 3 (STAT3) is regulated by the deacetylase SirT1. However, whether the newly described non-genomic actions of STAT3 toward mitochondrial oxidative phosphorylation
Vytautas Reipa, Jonghoon Choi, Nam S. Wang, Victoria M. Hitchins, Peter L. Goering, Robert Malinauskas
In anticipation of the increased use of various forms of silver as an antimicrobial agent in medical devices, the objective of this study was to evaluate the in vitro hemolytic potential of silver nanoparticles in dilute human blood, and to relate particle
Michael S. Waters, Bin (. Yang, Nancy J. Lin, Sheng Lin-Gibson
Evaluating the efficacy of dental materials to protect human teeth requires the capacity to measure tooth accurately and precisely decay. Current practices for determining tooth decay are destructive, qualitative to lowly quantitative, and/or measure bulk
Benjamin R. Galloway, Adele Peskin, Zachary H. Levine
RECIST (Response Evaluation Criteria in Solid Tumors) is a linear measure intended to predict tumor volume in medical computed tomography (CT). In this work, using purely geometrical considerations, we estimate how well RECIST can predict the volume of
Kaushik Chatterjee, Marian F. Young, Carl Simon Jr.
Optimizing cell-material interactions is critical towards maximizing regeneration in tissue engineering. Combinatorial and high-throughput (CHT) methods can be used to systematically screen tissue scaffolds to identify optimal biomaterial properties
Carl G. Simon Jr., Kaushik Chatterjee, Limin Sun, Laurence C. Chow, Marian F. Young
Current methods for combinatorial and high-throughput (CHT) screening of cell-material interactions utilize a two-dimensional (2D) format where cells are presented on flat materials surfaces [1]. However, cell response in 3D scaffolds is more
Structural properties of polymeric scaffolds for tissue engineering play a key role in directing osteogenesis. These properties depend on the chemical nature and the fabrication process of biomaterial. There are many protocols for fabricating scaffolds for
Carl G. Simon Jr., Girish Kumar, Christopher K. Tison
Utilizing tissue scaffold architecture to induce stem cell differentiation is of tremendous importance to the regenerative medicine community. To this end, we have investigated the effect of nanofiber scaffold structure on primary human bone marrow stromal
Reference scaffolds characterized for cell response are being developed for use as a standard for biological characterization of new scaffolds. The need for reference scaffolds to serve as a calibration standard between labs has been identified as critical
Carl G. Simon Jr., Kaushik Chatterjee, Stevephen Hung
Protein adsorption mediates biological responses to materials. When a biodegradable polymer scaffold is placed in aqueous, physiological medium, proteins adsorb onto the scaffold surface. The total amount, composition and structure of the adsorbed protein
Joy P. Dunkers, Kaushik Chatterjee, Carl G. Simon Jr.
Diffusion of oxygen in cell/scaffold construct interior is of critical importance to cell viability in constructs of clinically relevant sizes. It has been shown that depletion of oxygen within the scaffold leads to a decrease in cell density and viability
Joy P. Dunkers, Hae-Jeong Lee, Marvi Matos, Lisa Pakstis, Juan M. Taboas, Steven D. Hudson, Marcus T. Cicerone
When culturing cells on flexible surfaces, it is important to consider extracellular matrix treatments that will remain on the surface under mechanical strain. Here we investigate differences in laminin surfaces that were deposited on oxidized PDMS (plasma