Articles by Steven L. Goodman in JoVE
Verwendung von Kapseln zur Negativfärbung von Virusproben im Biocontainment Candace D. Blancett1, Mitchell K. Monninger1, Chrystal A. Nguessan1, Kathleen A. Kuehl1, Cynthia A. Rossi2, Scott P. Olschner2, Priscilla L. Williams2, Steven L. Goodman3, Mei G. Sun1 1Pathology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), 2Diagnostic Systems Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), 3Microscopy Innovations LLC Dieses Protokoll liefert eine Anleitung für Negativfärbevirusproben, die leicht in BSL-2-, -3- oder -4-Laboratorien verwendet werden können. Es beinhaltet die Verwendung einer innovativen Verarbeitungskapsel, die das Transmissionselektronenmikroskopie-Gitter schützt und dem Anwender eine leichtere Handhabung in den turbulenteren Umgebungen im Biokontainment ermöglicht.
Other articles by Steven L. Goodman on PubMed
New Photoaktivatoren Für Multiphotonen Aufgeregt Dreidimensionale Submikron Vernetzung Von Proteinen: Rinderserumalbumin Und Typ-1-Kollagen Photochemistry and Photobiology. Aug, 2002 | Pubmed ID: 12194208 We report the synthesis and optical characterization of two new photoactivators and demonstrate their use for multiphoton excited three-dimensional free-form fabrication with proteins. These reagents were developed with the goal of cross-linking Type 1 collagen. This cross-linking process produces structures on the micron and submicron size scales. A rose bengal diisopropyl amine derivative combines the classic photoactivator and co-initiator system into one molecule, reducing the reaction kinetics and increasing cross-linking efficiency. This derivative was successful at producing stable structures from collagen, whereas rose bengal alone was not effective. A benzophenone dimer connected by a flexible diamine tether was also synthesized. This activator has two photochemically reactive groups and is highly efficient in cross-linking bovine serum albumin and Type 1 collagen to form stable, robust structures. This approach is more flexible in terms of cross-linking a variety of proteins than by traditional benzophenone photochemistry. The photophysical properties vary greatly from that of benzophenone, with the appearance of a new, lower energy absorption band (lambda max approximately 370 nm in water) and broad, visible emission band (approximately 500 nm maximum). This absorption band is highly solvatochromic, suggesting it arises, at least in part, from a charge transfer interaction. Collagens are typically difficult to cross-link photochemically, and the results here suggest that these two new activators will be suitable for cross-linking other forms of collagen and additional proteins for biomedical applications such as the de novo assembly of biomimetic tissue scaffolds.
Platelet Responses to Silicon-alloyed Pyrolytic Carbons Journal of Biomedical Materials Research. Part A. Oct, 2007 | Pubmed ID: 17380499 Pyrolytic carbon (PYC) containing approximately 7 wt % silicon is used in most clinical mechanical heart valves where it has demonstrated a high level of blood compatibility. The Si, present as SiC, is included since it is believed to enhance durability. However, it has been suggested that SiC reduces PYC blood compatibility. In the present study, PYC valve leaflets were prepared with low, conventional, and high levels of Si. The in vitro responses of human platelets to these materials were then quantified. Platelet responses were consistent with previous reports: Adherent platelets were extremely well spread, closely followed submicron contours, and formed very few aggregates or microthrombi-like structures. No significant differences with respect to the Si concentrations were observed for platelets adherent per unit area and the numbers of thrombi-like structures. Some differences were observed with platelet morphologies and the material surface covered with platelets, although these did not vary consistently with respect to Si concentration. These results indicate that lowering (or raising) the Si alloy concentration in PYC over a reasonable range (0.54-13.5 wt % as examined here) is unlikely to improve or otherwise alter the in vivo blood compatibility of this important clinical material.
Preparation of Viral Samples Within Biocontainment for Ultrastructural Analysis: Utilization of an Innovative Processing Capsule for Negative Staining Journal of Virological Methods. Dec, 2016 | Pubmed ID: 27751950 Transmission electron microscopy can be used to observe the ultrastructure of viruses and other microbial pathogens with nanometer resolution. In a transmission electron microscope (TEM), the image is created by passing an electron beam through a specimen with contrast generated by electron scattering from dense elements in the specimen. Viruses do not normally contain dense elements, so a negative stain that places dense heavy metal salts around the sample is added to create a dark border. To prepare a virus sample for a negative stain transmission electron microscopy, a virus suspension is applied to a TEM grid specimen support, which is a 3mm diameter fragile specimen screen coated with a few nanometers of plastic film. Then, deionized (dI) water rinses and a negative stain solution are applied to the grid. All infectious viruses must be handled in a biosafety cabinet (BSC) and many require a biocontainment laboratory environment. Staining viruses in biosafety levels (BSL) 3 and 4 is especially challenging because the support grids are small, fragile, and easily moved by air currents. In this study we evaluated a new device for negative staining viruses called mPrep/g capsule. It is a capsule that holds up to two TEM grids during all processing steps and for storage after staining is complete. This study reports that the mPrep/g capsule method is valid and effective to negative stain virus specimens, especially in high containment laboratory environments.