Articles by Candace D. Blancett in JoVE
Utilización de cápsulas para la tinción negativa de muestras víricas en biocontención 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 Este protocolo proporciona instrucciones para muestras de virus de tinción negativas que pueden usarse fácilmente en laboratorios BSL-2, -3 o -4. Incluye el uso de una cápsula de procesamiento innovadora que protege la rejilla de microscopía electrónica de transmisión y proporciona al usuario un manejo más fácil en los ambientes más turbulentos dentro de la biocontención.
Other articles by Candace D. Blancett on PubMed
Serum Biomarkers of Burkholderia Mallei Infection Elucidated by Proteomic Imaging of Skin and Lung Abscesses Clinical Proteomics. 2015 | Pubmed ID: 26034464 The bacterium Burkholderia mallei is the etiological agent of glanders, a highly contagious, often fatal zoonotic infectious disease that is also a biodefense concern. Clinical laboratory assays that analyze blood or other biological fluids are the highest priority because these specimens can be collected with minimal risk to the patient. However, progress in developing sensitive assays for monitoring B. mallei infection is hampered by a shortage of useful biomarkers.
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.
Accurate Virus Quantitation Using a Scanning Transmission Electron Microscopy (STEM) Detector in a Scanning Electron Microscope Journal of Virological Methods. Jun, 2017 | Pubmed ID: 28668710 A method for accurate quantitation of virus particles has long been sought, but a perfect method still eludes the scientific community. Electron Microscopy (EM) quantitation is a valuable technique because it provides direct morphology information and counts of all viral particles, whether or not they are infectious. In the past, EM negative stain quantitation methods have been cited as inaccurate, non-reproducible, and with detection limits that were too high to be useful. To improve accuracy and reproducibility, we have developed a method termed Scanning Transmission Electron Microscopy - Virus Quantitation (STEM-VQ), which simplifies sample preparation and uses a high throughput STEM detector in a Scanning Electron Microscope (SEM) coupled with commercially available software. In this paper, we demonstrate STEM-VQ with an alphavirus stock preparation to present the method's accuracy and reproducibility, including a comparison of STEM-VQ to viral plaque assay and the ViroCyt Virus Counter.