Search results for " virus"

Study of the interactions between Broad bean wilt virus 1 and its host plants

Broad bean wilt virus 1 (BBWV-1) is the type member of the Fabavirus genus, in the Secoviridae family. BBWV-1 is worldwide distributed and infects important horticultural and ornamental crops causing considerable economic losses. However, information about the biological and molecular characteristics of BBWV-1 isolates is scarce. BBWV-1 is composed of two molecules of positive single-stranded RNA (ssRNA+) that are separately encapsidated in virions of icosahedral morphology. Each ssRNA+ encodes polyproteins which are processed by proteolytic cleavage into functional peptides. RNA1 (~ 5.8 kb) encodes for one polyprotein that renders proteins involved in viral replication: a protease cofactor…

New developments in the management of hepatitis C virus infection: focus on boceprevir

2012

Chronic hepatitis C virus infection is an important public health problem, and the standard treatment (combination of pegylated interferon-α and ribavirin) has an effectiveness rate of only 40%-50%. Novel virus-specific drugs have recently been designed, and multiple compounds are under development. The approval for the clinical use of direct-acting antivirals in 2011 (boceprevir [BOC] and telaprevir, viral NS3 protease inhibitors) has increased recovery rates by up to 70%. Therefore, a highly effective treatment has been envisioned for the first time. This paper focuses on BOC and the implementation of new BOC-based treatment regimes.

Nonlinearities in plant RNA virus fitness

2012

Una de las mayores amenazas tanto para la salud humana y animal, como para la agronomía es la emergencia de nuevas enfermedades infecciosas, la mayoría de las cuales están causadas por los virus de RNA. La emergencia viral es un problema complejo que consista en la adquisición de la variación genética, por mutación o recombinación, dentro de la población viral en el huésped reservorio la cual podría facilitar la capacidad de infectar de manera eficiente nuevos huéspedes. Los virus de RNA presentan a una evolucionabilidad extraordinaria por sus grandes tamaños poblacionales, cortos tiempos de generación y altas tasas de mutación y recombinación. Comprender los mecanismos evolutivos que podrí…

Experimental evolution of genome architecture and complexity in an RNA virus

2016

Introducción La evolución de la arquitectura del genoma – las dimensiones y la organización del material hereditario de un organismo – es poco conocida. Existe una variación asombrosa en la arquitectura genómica entre diferentes organismos. Los virus tienden a tener genomas pequeños, con un mínimo de secuencias intergénicas y típicamente con genes solapantes, los cuales se cree son una forma de compresión del genoma que permite al virus incrementar su número de proteínas sin aumentar su tamaño. Los procariotas tienen genomas compactos, pero con secuencias intergénicas más largas que los virus, y los genes con solapamientos largos son escasos. Los eucariotas presentan una amplia gama de tama…

Modelling the removal and reversible immobilization of murine noroviruses in a Phaeozem under various contamination and rinsing conditions

2018

International audience; Enteric viruses entering the soil with contaminated irrigation water can reach groundwater or be internalized in plants through their roots without being inactivated. Their fate in the soil depends on the virus, the soil and the soil solution. In order to write a mathematical model suitable for a Calcaric Phaeozem, we investigated the removal of murine norovirus and reversible immobilization in aggregate columns according to a saturation procedure, conditions between contamination and rinsing time, temperature and soil solution. Viruses were quantified before and after 0.45‐μm filtration with an RT‐qPCR (real‐time polymerase chain reaction). Experimental results supp…

Microtubules and microfilaments in HSV-Infected rabbit-kidney cells.

1981

In rabbit kidney cells infected with strains of Herpes simplex virus producing either cell-rounding or polycaryocytosis. Vinblastine induced paracrystals. This could be shown by phase-contrast- and electron-microscopy. Infections were done under one-step-growth conditions or at low MOI. 90 per cent noninfected cells contained stress fibers as detected by Servablue R250-staining. Shortly after recruitment into polycaryocytes, stress fibres of normal length appearing in criss-cross arrangement can be seen in the periphery of these cells. Later they polymerize to very long fibers and finally they are partially destroyed. The time of destruction depends on the MOI employed. By using Actinomycin…

Vaginal infection of mice with HSV type 2 variant ER−: A new animal model for human primary genital HSV type 2 infections

1992

Abstract Studying the pathogenesis of vaginal infections in mice with two variants of Herpes simplex virus type 2 (HSV-2) strain ER we observed that both variants ER+ and ER− caused severe vaginitis but only ER+ invaded the CNS leading to lethal neurological disease. In contrast, mice infected with ER− cleared the virus from the vagina and recovered from infection. ER+ and ER− expressed equal levels of thymidine kinase (TK) indicating a TK-independent difference in neurovirulence. Using the non-neurovirulent variant ER−, we were able to investigate humoral immune responses late after infection. Vaginal infection with ER− suppressed serum antibody formation after a secondary systemic HSV-1 i…

The effect of carvacrol on enteric viruses.

2014

Carvacrol, a monoterpenic phenol, is said to have extensive antimicrobial activity in a wide range of food spoilage or pathogenic fungi, yeast and bacteria. The aim of this study was to assess its antiviral activity on norovirus surrogates, feline calicivirus (FCV), murine norovirus (MNV), and hepatitis A virus (HAV), as well as its potential in food applications. Initially, different concentrations of carvacrol (0.25, 0.5, 1%) were individually mixed with each virus at titers of ca. 6-7 log TCID50/ml and incubated 2h at 37°C. Carvacrol at 0.5% completely inactivated the two norovirus surrogates, whereas 1% concentration was required to achieve ca. 1 log reduction of HAV. In lettuce wash wa…

Conformational Dynamics of the Dengue Virus Protease Revealed by Fluorescence Correlation and Single-Molecule FRET Studies.

2021

The dengue virus protease (DENV-PR) represents an attractive target for counteracting DENV infections. It is generally assumed that DENV-PR can exist in an open and a closed conformation and that active site directed ligands stabilize the closed state. While crystal structures of both the open and the closed conformation were successfully resolved, information about the prevalence of these conformations in solution remains elusive. Herein, we address the question of whether there is an equilibrium between different conformations in solution which can be influenced by addition of a competitive inhibitor. To this end, DENV-PR was statistically labeled by two dye molecules constituting a FRET …

Infection-induced chromatin modifications facilitate translocation of herpes simplex virus capsids to the inner nuclear membrane

2021

Herpes simplex virus capsids are assembled and packaged in the nucleus and move by diffusion through the nucleoplasm to the nuclear envelope for egress. Analyzing their motion provides conclusions not only on capsid transport but also on the properties of the nuclear environment during infection. We utilized live-cell imaging and single-particle tracking to characterize capsid motion relative to the host chromatin. The data indicate that as the chromatin was marginalized toward the nuclear envelope it presented a restrictive barrier to the capsids. However, later in infection this barrier became more permissive and the probability of capsids to enter the chromatin increased. Thus, although …