The development of novel nucleoside analogues for the formation of triplex DNA containing pyrimidine-purine inversion sites has been a challenging field. In this paper, we describe the design and synthesis of non-natural nucleoside analogues, N-substituted-2'-deoxy-5-methylisocytidine derivatives, and their evaluation for triplex formation. It has been shown that N-(guanidinoethyl)-2'-deoxy-5-m...

Fluorinated nucleoside analogues are known as antitumor, antiviral and chemotherapeutic agents, although the antioxidant activity of this kind of molecules is not yet investigated. In this study we have tested the antioxidant activity of a series of modified pyrano-nucleoside analogues using three in vitro assays. Firstly, the antioxidant capacity of the products was assessed using the DPPH ass...

BACKGROUND AND AIMS We aimed to evaluate the effectiveness of nucleoside analogues such as Lamivudine, Adefovir,Entacavir, and Tenofovir in patients with chronic hepatitis B who failed to respond to interferon therapy and relapsed. MATERIALS AND METHODS We followed a total of 73 patients with hepatitis B in the hepatitis outpatient clinic in our hospital. The patients subsequently received nu...

DNA topoisomerase I (Topo I) can exist in several different molecular weight forms in human leukemic cells. The Mr 98,000 form of Topo I was inhibited by several nucleoside triphosphates and their analogues at a 500 microM concentration in the order: dideoxy-GTP greater than 2-bromo-dATP greater than dideoxy-ATP greater than dideoxy-CTP greater than 2-fluoro-dATP greater than 2-chloro-dATP. The...

BACKGROUND Direct acting antivirals (DAA) targeting the HCV serine protease and RNA polymerase have recently entered clinical development. Information about primary resistance to these compounds in HIV-HCV-coinfected patients is scarce. METHODS All individuals newly diagnosed with HIV-1 at several clinics in Madrid between 2000 and 2010 were tested for serum HCV antibody and HCV RNA. The NS3 ...

The mechanisms of resistance to nucleoside analogues established in preclinical models are rarely found in primary tumors resistant to therapy with these agents. We tested the hypothesis that cells sense sublethal incorporation of analogues into DNA during replication and react by arresting further DNA synthesis and cell cycle progression. After removal of drug, cells may be able to repair dama...