tailieunhanh - Báo cáo y học: " Nuclease-resistant double-stranded DNA controls or standards for hepatitis B virus nucleic acid amplification assays"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Nuclease-resistant double-stranded DNA controls or standards for hepatitis B virus nucleic acid amplification assays | Virology Journal BioMed Central Research Nuclease-resistant double-stranded DNA controls or standards for hepatitis B virus nucleic acid amplification assays Shuang Meng1 2 Sien Zhan1 2 and Jinming Li 2 Open Access Address Graduate School Peking Union Medical College Chinese Academy of Medical Sciences PR China and 2National Center for Clinical Laboratories Beijing Hospital Beijing PR China Email Shuang Meng-xluhua@ Sien Zhan - zhansien81@ Jinming Li - ljm63hn@ Corresponding author Published 22 December 2009 Received 27 October 2009 Accepted 22 December 2009 Virology Journal 2009 6 226 doi 1743-422X-6-226 This article is available from http content 6 1 226 2009 Meng et al licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract Background Identical blood samples tested using different kits can give markedly different hepatitis B virus HBV DNA levels which can cause difficulty in the interpretation of viral load. A universal double-stranded DNA control or standard that can be used in all commercial HBV DNA nucleic acid amplification assay kits is urgently needed. By aligning all HBV genotypes A-H we found that the surface antigen gene and precore-core gene regions of HBV are the most conserved regions among the different HBV genotypes. We constructed a chimeric fragment by overlapping extension polymerase chain reaction and obtained a 1 349-bp HBVC S fragment. We then packaged the fragment into lambda phages using a traditional lambda phage cloning procedure. Results The obtained armored DNA was resistant to DNase I digestion and was stable noninfectious to humans and could be easily extracted using commercial kits. More importantly the armored DNA may be used with all HBV