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Microstructures of biomedical scaffolds can greatly affect cellular activities in tissue regeneration. In particular, scaffolds used in bone tissue regeneration should have several microstructural characteristics, including high porosity, appropriate pore
William Sparks, James H. Hough, Thomas Germer, Frank Robb, Ludmilla Kolokolova
We describe circular polarization as a remote sensing diagnostic of chiral signatures which may be applied to Mars. The remarkable phenomenon of homochirality provides a unique biosignature which can be amenable to remote sensing through circular
Conni Hanke, Petra S. Dittrich, Darwin Reyes-Hernandez
A cell co-culture was generated on opposite sides of a permeable polyester membrane (PET) membrane by combining dielectrophoretic (DEP) and electrostatic forces to hold cells against gravity in a multilayer microfluidic device (Figure 1). HepG2 cells were
Background Characterization of whole transcriptomes from small RNA samples (less than 1 ng total RNA) has been a major challenge. Typically, samples are extracted and purified, amplified by in vitro transcription (IVT), and then subjected to genome-scale
This paper addresses the problem of mapping application specific requirements on image similarity metrics to the plethora of existing image similarity computations. The work is motivated by the fact that there is no recommendation method for choosing a
Shiv Kumar, Tao Chuanjuan, Chien Minchen, Hellner Brittney, Joseph W. Robertson, Arvind Balijepalli, Li Zengmin, James J. Russo, Joseph E. Reiner, John J. Kasianowicz, Jingyue Ju
There is a significant need to accurately sequence single DNA and RNA molecules for personalized medicine. We describe a novel nanopore-based sequencing by synthesis (SBS) strategy that will accurately differentiate at single molecule level four different
Simona Bancos, De-Hao D. Tsai, Vincent A. Hackley, J L. Weaver, Katherine M. Tyner
Nanoparticles (NPs) are known to interfere with many high throughput cell viability and cell proliferation assays, which complicates the assessment of their potential toxic effects. The aim of this study was to compare viability and proliferation results
Justin M. Zook, Melissa D. Halter, Danielle Cleveland, Stephen E. Long
Silver nanoparticles (AgNPs) are frequently coated by a variety of polymers, which may affect various intertwined mechanisms of toxicity, including agglomeration and dissolution rate. Here, we measure how citrate, dextran, poly(ethylene glycol) (PEG)
Few technologies are more widespread in modern biological laboratories than imaging by microscopy. Advancements in optical technologies and instrumentation over the past twenty years have led to massive improvements in the resolution, specificity
A procedure is described for assigning the number of equivalent reference fluorophores (ERF) values to microspheres labeled with a fluorophore designed to produce a fluorescence response in a given fluorescence channel of a multicolor flow cytometer. The
Maritoni A. Litorja, Robert C. Chang, Jeeseong Hwang, David W. Allen
The determination of the level of oxygenation in optically accessible tissues using multispectral or hyperspectral imaging (HSI ) of oxy- and deoxyhemoglobin has special appeal in clinical work due to its non-invasiveness, ease of use and capability of
Autumn S. Downey, Sandra M. Da Silva, Jayne B. Morrow, James J. Filliben, Nathanael D. Olson
Environmental sampling for microbiological contaminants is a key component of hygiene monitoring and risk characterization practices utilized across diverse fields of application. However, confidence in surface sampling results, both in the field and in
Justin M. Zook, Daniel V. Samarov, Jennifer H. McDaniel, Shurjo Sen, Marc L. Salit
While the importance of random sequencing errors decreases at higher DNA or RNA sequencing depths, systematic sequencing errors (SSEs) dominate at high sequencing depths and can be difficult to distinguish from biological variants. These SSEs can cause
Tighe Spurlin, John T. Elliott, Michael W. Halter, Kiran Bhadriraju, Alessandro Tona, Anne L. Plant, Annalaura Mancia, Bobby L. Middlebrooks, Gregory W. Warr
Descriptive terms are often used to characterize cells in culture, but the use of nonquantitative and poorly defined terms can lead to ambiguities when comparing data from different laboratories. Although recently there has been a good deal of interest in
Jin Chu Wu, Michael W. Halter, Raghu N. Kacker, John T. Elliott
Cell image segmentation (CIS) is critical for quantitative imaging in cytometric analyses. The data derived after segmentation can be used to infer cellular function. To evaluate CIS algorithms, first for dealing with comparisons of single cells treated as
Neuron-specific in vitro screening strategies have the potential to accelerate the evaluation of chemicals or nanomaterials for neurotoxicity. We examined the effect of lithium ion, which is known to inhibit neurite outgrowth in neuron monocultures, on rat
Illarion V. Turko, Meiyao Wang, Gun-Young Heo, Saida Omarova, Irina A. Pikuleva
Quantitative analysis of low-abundance membrane proteins remains a challenge and requires further optimization of analytical methods developed for their soluble counterparts. Use of stable isotope-labeled full-length proteins as an internal standard in
Conni Hanke, Petra S. Dittrich, Darwin Reyes-Hernandez
We present a new system for cell capturing on permeable polyester (PET) membranes using dielectrophoretic forces. For the first time gold microelectrodes were fabricated on PET membranes using conventional photolithographic techniques. Their
To transform the linear fluorescence intensity scale obtained with fluorescent microspheres to an antibody bound per cell (ABC) scale, a biological cell reference material is needed. Optimally, this material should have a reproducible and tight ABC value
David Gallagher, Janet Newman, Evan E. Bolton, Jochen M?Dieckmann, Vincent J. Fazio, David Lovell, Joseph R. Luft, Thomas S. Peat, David Ratcliffe, Roger A. Sayle, Edward H. Snell, Kerry Taylor, Pascal Vallotton, Sameer Velankar, Frank V. Delft
Crystallisation of biological macromolecules is seen by most structural biologists as a necessary evil, a means to the end, which is knowledge about a macromolecular structure. Crystallization remains largely a trial-and-error process, with extensive
David W. Allen, Jeeseong Hwang, Maritoni A. Litorja, Joseph P. Rice
Biomedical optical imaging has the potential to achieve high spatial resolution and high functional sensitivity for non-invasive assessment of ischemic wounds. However, clinical acceptance of many optical imaging devices is hampered by poor reproducibility
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
Zvi Kelman, Jerard Hurwitz, Wiebke Chemnitz Galal, Miao Pan
In most organisms, DNA replication is initiated by DNA primases which synthesize primers that are elongated by DNA polymerases. In this report we describe the isolation and biochemical characterization of the DNA primase complex and its subunits from the
Zvi Kelman, John P. Marino, Jerard Hurwitz, Wiebke Chemnitz Galal, Miao Pan, Gary Giulian, Wei Yuan, Shuwei Li
In the presence of dATP, glycerol and Tris buffer, the DNA primase isolated from Thermococcus kodakaraensis (Tk) catalyzed the formation of two products that were identified as dAMP-glycerol and dAMP-Tris. These products were formed by the Tk p41 catalytic