1. The hemagglutinating capacity, enzymic activity, and infectivity of several influenza viruses were destroyed by repeated freezing and thawing of dialyzed allantoic fluids containing them. 2. Influenza virus degraded by freezing and thawing, by treatment with 5 M urea, or by heating at 65 degrees C. still combined with homologous antibody and was demonstrable by blocking of the hemagglutinati...

Fluid-free alveolar space is critical for normal gas exchange. Influenza virus alters fluid transport across respiratory epithelia producing rhinorrhea, middle ear effusions, and alveolar flooding. However, the mechanism of fluid retention remains unclear. We investigated influenza virus strain A/PR/8/34, which can attach and enter mammalian cells but is incapable of viral replication and produ...

The seasonality of influenza virus infections in temperate climates and the role of environmental conditions like temperature and humidity in the transmission of influenza virus through the air are not well understood. Using ferrets housed at four different environmental conditions, we evaluated the respiratory droplet transmission of two influenza viruses (a seasonal H3N2 virus and an H3N2 var...

BACKGROUND Early recognition of influenza virus infection in hospitalized patients can prevent nosocomial transmission. OBJECTIVE To determine the clinical presentation of influenza in hospitalized patients. DESIGN Case series. Data were collected retrospectively from medical records and included demographic information, comorbidities, clinical symptoms and signs, microbiologic test results...

Sphingosine 1-phosphate (S1P)-metabolizing enzymes regulate the level of sphingolipids and have important biological functions. However, the effects of S1P-metabolizing enzymes on host defense against invading viruses remain unknown. In this study, we investigated the role of S1P-metabolizing enzymes in modulating cellular responses to influenza virus infection. Overexpression of S1P lyase (SPL...

Viral ion channels are short auxiliary membrane proteins with a length of ca. 100 amino acids. They are found in enveloped viruses from influenza A, influenza B and influenza C (Orthomyxoviridae), and the human immunodeficiency virus type 1 (HIV-1, Retroviridae). The channels are called M2 (influenza A), NB (influenza B), CM2 (influenza C) and Vpu (HIV-1). Recently, in Paramecium bursaria chlor...

background and aims: vaccination is the most effective method to prevent influenza infection. among the available vaccines, cold-adapted live-virus vaccines are suitable approach that have been produced and evaluated for recent years in few countries. the goal of this project was to derivate a cold adapted variant of the influenza a/new caledonia/20/1999(h1n1). materials and methods: influenza ...

BACKGROUND MHC class I-restricted CD8+ cytotoxic T lymphocytes (CTL) are thought to play a major role in clearing virus and promoting recovery from influenza infection and disease. This has been demonstrated for clearance of influenza virus from the lungs of infected mice. However, human influenza infection is primarily a respiratory mucosal infection involving the nasopharynx and tracheobronch...

We describe a synthetic sialic acid analogue, 9-thioacetamido-N-acetylneuraminic acid (9-thioacetamido-Neu5Ac), which is recognized by the receptor-binding activity of influenza C virus, but is resistant to the receptor-destroying enzyme (acetylesterase) of this virus. Following transfer of the analogue to the surface of receptor-negative cells, influenza C virus is able to attach to these cell...