Biosafety Level (biosafety + level)

Distribution by Scientific Domains


Selected Abstracts


Synthesis and in vitro Efficacy Studies of Silver Carbene Complexes on Biosafety Level 3 Bacteria

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2009
Matthew J. Panzner
Abstract A series of N-heterocyclic carbene silver complexes have been synthesized and tested against the select group of biosafety level 3 bacteria Burkholderia pseudomallei, Burkholderia mallei, Bacillus anthracis, methicillin-resistant Staphylococcus aureus and Yersinia pestis. Minimal inhibitory concentrations, minimal bactericidal and killing assays demonstrated the exceptional efficacy of the complexes against these potentially weaponizable pathogens. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]


Crystal structures of Nipah and Hendra virus fusion core proteins

FEBS JOURNAL, Issue 19 2006
Zhiyong Lou
The Nipah and Hendra viruses are highly pathogenic paramyxoviruses that recently emerged from flying foxes to cause serious disease outbreaks in humans and livestock in Australia, Malaysia, Singapore and Bangladesh. Their unique genetic constitution, high virulence and wide host range set them apart from other paramyxoviruses. These characteristics have led to their classification into the new genus Henpavirus within the family Paramyxoviridae and to their designation as Biosafety Level 4 pathogens. The fusion protein, an enveloped glycoprotein essential for viral entry, belongs to the family of class I fusion proteins and is characterized by the presence of two heptad repeat (HR) regions, HR1 and HR2. These two regions associate to form a fusion-active hairpin conformation that juxtaposes the viral and cellular membranes to facilitate membrane fusion and enable subsequent viral entry. The Hendra and Nipah virus fusion core proteins were crystallized and their structures determined to 2.2 Å resolution. The Nipah and Hendra fusion core structures are six-helix bundles with three HR2 helices packed against the hydrophobic grooves on the surface of a central coiled coil formed by three parallel HR1 helices in an oblique antiparallel manner. Because of the high level of conservation in core regions, it is proposed that the Nipah and Hendra virus fusion cores can provide a model for membrane fusion in all paramyxoviruses. The relatively deep grooves on the surface of the central coiled coil represent a good target site for drug discovery strategies aimed at inhibiting viral entry by blocking hairpin formation. [source]


Rapid diagnosis of coccidioidomycosis by nested PCR assay of sputum

CLINICAL MICROBIOLOGY AND INFECTION, Issue 4 2007
R. De Aguiar Cordeiro
Abstract Coccidioidomycosis is a deep infection caused by two dimorphic fungi, Coccidioides immitis and Coccidioides posadasii. Diagnosis of the disease requires culture of suspicious clinical samples on mycological media. However, as these species are virulent pathogens, handling of their cultures is a high-risk activity, and is limited to Biosafety Level 3 laboratories. This study describes the direct detection of C. posadasii DNA in an inappropriate sputum sample by PCR amplification of the highly specific Ag2/PRA antigen gene. The results obtained suggest that direct detection of the Ag2/PRA sequence in sputum is an excellent method for rapid and specific diagnosis of coccidioidomycosis. [source]


Synthesis and in vitro Efficacy Studies of Silver Carbene Complexes on Biosafety Level 3 Bacteria

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2009
Matthew J. Panzner
Abstract A series of N-heterocyclic carbene silver complexes have been synthesized and tested against the select group of biosafety level 3 bacteria Burkholderia pseudomallei, Burkholderia mallei, Bacillus anthracis, methicillin-resistant Staphylococcus aureus and Yersinia pestis. Minimal inhibitory concentrations, minimal bactericidal and killing assays demonstrated the exceptional efficacy of the complexes against these potentially weaponizable pathogens. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]


Phenotypic analysis of the sensitivity of HIV-1 to inhibitors of the reverse transcriptase, protease, and integrase using a self-inactivating virus vector system

JOURNAL OF MEDICAL VIROLOGY, Issue 3 2001
Gergely Jįrmy
Abstract Conventional phenotypic analysis of resistance of the human immunodeficiency virus (HIV) to antiviral therapy is time-consuming and requires culture of infectious virus. Although phenotypic analyses may be desirable, rapid generation of test results and decentralized availability of the test system will be important to achieve utility in the clinical practice. This study describes the design of an alternative phenotypic resistance test using replication incompetent viral vectors. Chimeric HIV vectors containing a marker gene were generated. The env and most of the regulatory and accessory genes of HIV were removed. In addition, the 3,U3 region was deleted to obtain a self-inactivating construct. Cotransfection of the plasmid with a plasmid that provided the vesicular stomatitis virus glycoprotein resulted in the production of replication-incompetent virus vectors. Infection of susceptible cells with the vectors led to marker gene expression. Vector production in the presence of protease (PR) inhibitors, or infection in the presence of reverse transcriptase (RT) or integrase (IN) inhibitors reduced marker gene expression in a dose-dependent manner. Marker gene activity was preserved at higher drug levels if vectors contained RT and PR genes from resistant virus isolates. Sensitivity to nucleoside and non-nucleoside RT inhibitors, protease and integrase inhibitors could be determined in 10 working days. The phenotypic drug resistance test using replication-incompetent HIV vectors significantly speeds up drug resistance measurements and allows testing at reduced biosafety levels. This will make clinical use of phenotypic assessment of antiviral resistance more feasible. J. Med. Virol. 64:223,231, 2001. © 2001 Wiley-Liss, Inc. [source]