Abstract.As nitric oxide (NO) expression levels are lower in hepatocytes compared with other cell types, it is difficult to quantify this compound via Griess assay. The aim of the present study was to quantify NO concentration in the cell culture medium from a subgenomic hepatitis C virus (HCV)-replicon expressing Huh-7 cell system using a high-performance liquid chromatography (HPLC)-fluorescence detector in the presence or absence of acetylsalicylic acid (ASA) treatment. HCV-replicon cells were incubated with ASA (4 mM) for 24, 48 and 72 h. Thereafter, the medium was collected to measure nitrites (NO 2 -) as an indirect indicator of NO levels using diaminonaphtalene as a derivate agent. NO levels were significantly higher (1.7-fold) in Huh-7 replicon cells treated with ASA (72 h post-treatment) than untreated cells (P<0.05); NO inhibitor reduced ~30% the level of NO in Huh-7 replicon cells treated with ASA (48 h post-treatment; P<0.05). The findings suggested that the HPLC-fluorescence method provided an accurate and efficient measurement of NO production in Huh-7-HCV-replicon cells culture medium.

Research groups who develop scientific advances in bioinformatics and biotechnological drugs, biomaterials for tissue engineering and diagnostics methods based in nanotechnology already exist in Mexico. This chapter presents basic and introductory aspects of the definitions and outreach of each discipline, as well as an extensive list of the research groups and institutions where pertinent studies are carried out to provide an update about the main focus of each investigation team. The information provided may be useful to create inter and multidisciplinary teams and thereby foster substantial improvements in these research areas. In addition, national regulations required on the field of biotechnological drugs, biomaterials for tissue engineering and diagnostics devices are presented with the objective that related and innovative projects could be taken to the market for the benefit of our society.