Search results for "antiviral agent"
showing 10 items of 505 documents
Direct-acting antiviral agents and risk of hepatocellular carcinoma: is it still a clinical dilemma?
2019
Direct-acting antivirals (DAAs) revolutionised the treatment of chronic HCV-related disease achieving high rates of sustained virological response (SVR), also in more advanced patients, with a good safety profile and a proven positive effect on the reduction of risk of HCC occurrence. Nevertheless, patients with an history of successfully treated early HCC were initially excluded from pivotal trials. Although some initial retrospective studies, affected by several methodological issues, raised concerns regarding a possible harmful effect on the risk of HCC recurrence after antiviral therapy, more recent prospective studies and meta-analyses provided evidence that risk of HCC recurrence afte…
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…
Sulphoevernan, a polyanionic polysaccharide, and the narcissus lectin potently inhibit human immunodeficiency virus infection by binding to viral env…
1990
Sulphoevernan is a sulphated alpha-1----3, 1----4 polyglucan (Mr 20,000) with a helical structure. This compound effectively inhibits both human immunodeficiency virus type 1 (HIV-1) and type 2 infection of cells in vitro at concentrations around 0.5 micrograms/ml. Moreover, the compound completely inhibits HIV-1-induced syncytium formation at a concentration of 1 microgram/ml. Competition experiments with 35S-labelled sulphoevernan revealed that the mannose-specific lectin from Narcissus pseudonarcissus prevented binding of sulphoevernan to HIV-1, whereas the antibody OKT4A did not reduce the amount of sulphoevernan bound to MT-2 cells. These data indicate that the non-cytotoxic polymer su…
The biomaterial polyphosphate blocks stoichiometric binding of the SARS-CoV-2 S-protein to the cellular ACE2 receptor
2020
The effect of the polyanionic polymer of inorganic polyphosphate (polyP) involved in innate immunity on the binding of the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein to the cellular ACE2 receptor was studied. The RBD surface comprises a basic amino acid stretch of four arginine residues which interact with the physiological polyP (polyP40) and polyP3. Subsequently, the interaction of RBD with ACE2 is sensitively inhibited. After the chemical modification of arginine, an increased inhibition by polyP, at a 1 : 1 molar ratio (polyP : RBP), is measured already at 0.1 μg mL−1. Heparin was ineffective. The results suggest a potential therapeutic benefit of polyP against SARS-C…
NOVEL COMPOSED GALACTOSYLATED NANODEVICES CONTAINING A RIBAVIRIN PRODRUG AS HEPATIC CELL-TARGETED CARRIERS FOR HCV TREATMENT
2013
In this paper, we describe the preparation of liver-targeted nanoparticles potentially able to carry to hepatocytes a ribavirin (RBV) prodrug, exploiting the presence of carbohydrate receptors in the liver (i.e., ASGPR in hepatocytes). These particles were obtained starting from a galactosylated phospholipid-polyaminoacid conjugate. This latter was obtained by chemical reaction of ALPHA, BETA -poly(N-2-hydroxyethyl) (2-aminoethylcarbamate)-DL-aspartamide (PHEA-EDA) with 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-(succinyl) sodium salt (DPPE), and subsequent reaction with lactose, obtaining PHEA-EDA-DPPE-GAL copolymer. To enhance the entrapment into obtained nanostructures, a hydroph…
Eltrombopag in chronic hepatitis C
2014
Chronic hepatitis C is a public health problem worldwide. Unfortunately, not all patients may benefit from antiviral therapy due to thrombocytopenia. Its causes are represented by portal hypertension and platelet sequestration in the spleen, decreased serum levels or activity of thrombopoietin, the bone marrow suppression induced by hepatitis C virus and a possible adverse effect of interferon. Thrombopoietin receptor analogs may contribute to increase platelet counts in these patients. Eltrombopag binds to another region of the thrombopoietin receptor compared to endogenous thrombopoietin and stimulates the proliferation and maturation of megakaryocytes and the platelet production in a dos…
HCV genotype 5: an orphan virus
2013
HCV genotype 5 (HCV-5) is the least known HCV genotype. It is found mainly in South Africa and in restricted areas of Belgium, Spain, France, Syria and Greece. Sporadic cases are reported worldwide. The main modes of transmission are blood transfusion and iatrogenic causes. Little is known about its origin, but various studies have elucidated its spread worldwide. In endemic areas, patients infected with HCV-5 are on average older and have a higher viral load and more advanced fibrosis than those infected with non-HCV-5 genotypes. The current standard of care for HCV-5 chronic infection is 48 weeks of dual therapy with pegylated interferon plus ribavirin. ‘Favourable’ Il28B polymorphisms a…
First case in Italy of acquired resistance to oseltamivir in an immunocompromised patient with influenza A/H1N1v infection
2010
A pandemic influenza A/H1N1v strain with the neuraminidase H274Y mutation was detected in nasal secretions of a 2-year-old leukemic patient with influenza-like illness after 18 days of treatment with oseltamivir. At baseline, no drug-resistant virus was found, while 4 days after treatment initiation a mix- ture of wild-type and mutated virus was detected. After treatment interruption, the wild type influenza virus re-emerged and became prevalent in nasal secretions after a few days, suggesting the lower fitness of the mutated virus strain. The patient slowly improved concurrently with a decrease in virus load, which resulted negative 42 days after diagnosis. No other drug-resistant influenz…
The impact of DAA-mediated HCV eradication on CD4+ and CD8+ T lymphocyte trajectories in HIV/HCV coinfected patients: Data from the ICONA Foundation …
2021
HCV infection has been hypothesized as a contributor of poor CD4+ recovery in patients living with HIV (PLWHIV). Aim of this study was to evaluate CD4+, CD8+ cells and CD4/CD8 ratio trends before and after HCV treatment with direct acting agents (DAA) in PLWHIV. HIV/HCV patients enrolled in ICONA and HepaICONA cohorts with HIV-RNA≤50 copies/ml who achieved a sustained viral response after DAA treatment were studied. A linear regression model was used to investigate CD4+, CD8+ and CD4/CD8 changes 12 months before and after DAA treatment. A total of 939 HIV/HCV patients were included, 225 (24.0%) female, median age: 53 years (IQR 50–56). At DAA initiation, CD4+ T cell count was <350 cells/…
TyG index, HOMA score and viral load in patients with chronic hepatitis C due to genotype 1.
2011
Summary. The triglycerides × glucose (TyG) index is a recently proposed surrogate marker of insulin resistance (IR), calculated from fasting plasma triglyceride and glucose concentrations. We tested the host and viral factors associated with Tyg and homeostasis model assessment (HOMA) scores, comparing their associations with histological features and with sustained virological response (SVR) in patients with genotype 1 chronic hepatitis C(G1CHC). Three hundred and forty consecutive patients with G1CHC were considered. All had a liver biopsy scored by one pathologist for staging and grading (Scheuer), and graded for steatosis, which was considered moderate–severe if ≥30%. Anthropometric an…