Search results for "Viral Replication"
showing 10 items of 157 documents
An Assessment of the Effect of Human Herpesvirus-6 Replication on Active Cytomegalovirus Infection after Allogeneic Stem Cell Transplantation
2010
Human herpesvirus-6 (HHV-6) may enhance cytomegalovirus (CMV) replication in allogeneic stem cell transplant (allo-SCT) recipients either through direct or indirect mechanisms. Definitive evidence supporting this hypothesis are lacking. We investigated the effect of HHV-6 replication on active CMV infection in 68 allo-SCT recipients. Analysis of plasma HHV-6 and CMV DNAemia was performed by real-time PCR. Enumeration of pp65 and IE-1 CMV-specific IFNgamma CD8(+) and CD4(+)T cells was performed by intracellular cytokine staining. HHV-6 DNAemia occurred in 39.8% of patients, and was significantly associated with subsequent CMV DNAemia in univariate (P=.01), but not in multivariate analysis (P…
Role of cytomegalovirus (CMV)-specific polyfunctional CD8+ T-cells and antibodies neutralizing virus epithelial infection in the control of CMV infec…
2015
The role of cytomegalovirus (CMV)-specific polyfunctional CD8+ T-cells and that of antibodies neutralizing virus epithelial infection (AbNEI) in the control of CMV DNAemia were investigated in 39 CMV-seropositive allogeneic stem-cell transplant (Allo-SCT) recipients with (n = 24) or without (n = 15) CMV DNAemia. AbNEI levels were monitored prospectively by means of a neutralization assay employing retinal epithelial cells (ARPE-19) and the recombinant CMV strain BADrUL131-Y4. Quantification of CMV-specific polyfunctional CD8+ T-cells (expressing two or three of the following markers: IFN-γγ, TNF-α and CD107a) in whole blood was performed by flow cytometry for intracellular cytokine staining…
Rare pre-core stop-codon mutant nt. 1897 predominates over wide-spread mutant nt. 1896 in an unusual course of chronic hepatitis B
1996
We present a patient with an unusual course of hepatitis B e antigen (HBeAg)-negative chronic hepatitis B who had repeated reactivations of his disease progressing to cirrhosis with terminal liver failure. Each flare up presented like an acute hepatitis with very high titres of hepatitis B virus (HBV) and high inflammatory activity followed by rapid clearance of viraemia. The pre-core genome of HBV isolated from sera during 5 years of follow up was analysed. Direct sequencing of polymerase chain reaction (PCR) products derived from consecutive sera showed a rare pre-core stop-codon mutation at nucleotide (nt.) 1897 G --> A with an accompanying mutation nt. 1857 C --> T as well as a stop-cod…
Synthesis of new 2,3-diaryl-1,3-thiazolidin-4-ones as anti-HIV agents
2004
Several 2,3-diaryl-1,3-thiazolidin-4-ones were synthesized and evaluated as anti-HIV agents. The results of the in vitro tests showed that some of them were highly effective inhibitors of HIV-1 replication at 30-50 nM concentrations with minimal cytotoxicity, thereby acting as non-nucleoside HIV-1 reverse transcriptase inhibitors (NNRTIs).
Antibody Complementarity-Determining Regions (CDRs) Can Display Differential Antimicrobial, Antiviral and Antitumor Activities
2008
9 p. Background: Complementarity-determining regions (CDRs) are immunoglobulin (Ig) hypervariable domains that determine specific antibody (Ab) binding. We have shown that synthetic CDR-related peptides and many decapeptides spanning the variable region of a recombinant yeast killer toxin-like antiidiotypic Ab are candidacidal in vitro. An alanine-substituted decapeptide from the variable region of this Ab displayed increased cytotoxicity in vitro and/or therapeutic effects in vivo against various bacteria, fungi, protozoa and viruses. The possibility that isolated CDRs, represented by short synthetic peptides, may display antimicrobial, antiviral and antitumor activities irrespective of Ab…
Synthesis and biological evaluation of pyridinebetaine A and B
2009
The synthesis of the marine natural products pyridinebetaine A and B is reported. The biological evaluation of pyridinebetaine A and B and several analogues as cytotoxic, antifungal and antiviral agents is also described. Unfortunately, none of the compounds tested showed relevant antifungal or cytotoxic activity. Only pyridinebetaine B reduced the Herpes simplex virus type 1 virus replication, though only weakly.
Differential in vitro Anti-HIV Activity of Natural Lignans
1990
Abstract Two naturally occurring lignanolides, isolated from the tropical climbing shrub Ipomoea cairica, (-)-arctigen in and (-)-trachelogen in , were found to inhibit strongly replication of human immunodeficiency virus type 1 (HIV-1; strain HTLV-III B) in vitro. At a concentration of 0.5 (μм , (-)-arctigenin and (-)-trachelogenin inhibited the expression of HIV-1 proteins p 17 and p24 by 80 -90 % and 60 -70 % , respectively. The reverse transcriptase activity in the culture fluids was reduced by 80 -90 % when the cells (HTLV-III B/H 9) were cultivated in the presence of 0.5 μм (-)-arctigen in or 1 μм (-)-trachelogenin . At the same concentrations, the formation of syncytia in the HTLV-I…
Related haloarchaeal pleomorphic viruses contain different genome types
2012
Archaeal viruses have been the subject of recent interest due to the diversity discovered in their virion architectures. Recently, a new group of haloarchaeal pleomorphic viruses has been discovered. It is distinctive in terms of the virion morphology and different genome types (ssDNA/dsDNA) harboured by rather closely related representatives. To date there are seven isolated viruses belonging to this group. Most of these share a cluster of five conserved genes, two of which encode major structural proteins. Putative proviruses and proviral remnants containing homologues of the conserved gene cluster were also identified suggesting a long-standing relationship of these viruses with their ho…
Generation of lentivirus vectors using recombinant baculoviruses
2008
In spite of advances in conventional four-plasmid transient transfection methods and development of inducible stable production cell lines, production of replication-defective lentiviral vectors in clinical scale has been challenging. Baculovirus technology offers an alternative to scalable virus production as a result of fast and easy production of baculoviruses, efficient transduction of mammalian cells and safety of the baculoviruses. As a first step toward scalable lentiviral production system, we have constructed four recombinant baculoviruses: the BAC-transfer virus expresses green fluorescent protein (GFP) as a transgene and BAC-gag-pol, BAC-vesicular stomatitis virus glycoprotein G …
N-acetyl-L-cysteine (NAC) inhibit mucin synthesis and pro-inflammatory mediators in alveolar type II epithelial cells infected with influenza virus A…
2011
64% of chronic obstructive pulmonary disease (COPD) exacerbations are caused by respiratory infections including influenza (strains A and B) and respiratory syncytial virus (RSV). They affect the airway epithelium increasing inflammatory and apoptosis events through mechanisms involving ROS generation, and induce the release of mucins from epithelial cells that are involved in the deterioration of the patient's health during the course of the disease. The antioxidant NAC has proved useful in the management of COPD reducing symptoms, exacerbations and accelerated lung function decline. It has been shown to inhibit influenza virus replication and to diminish the release of inflammatory and ap…