The mechanism of biological actions of quercetin was studied by using metabolomic method and biomolecular network. HPLC-MS was used to analyze the serum metabolome in rats of blank group and quercetin administration group rats, and MS data were processed by MATLAB software. With multivariate statistical analysis of serum metabolite profiles, a clear separation among blank group and quercetin administration group was achieved, potential biomarkers were selected according to the parameters of variable importance in the projection (VIP) and identified according to MS information and database retrieval. Four compounds, related enzymes, action targets and metabolic pathways had been confirmed, namely retinoic acid and RARbeta, arachidonate and COX-2, 3, 5-diodotyrosine and TPO, uridine diphosphate glucose and PDEs. The mechanism of quercetin enhancing ability of retinoic acid on the induction of RARbeta, activating TPO, using as COX-2 and PDEs inhibitor was approved by biomolecular network and related literatures. In this study, a mechanism of multiple biological actions of quercetin was evaluated at the level of the biomolecular network, metabolomics and biomolecular network can be used to investigate the biological effects mechanism of quercetin, which provided a new method to further revealing mechanism of drug action.

Objective To investigate the subtype distribution of HIV-1 infection among men having sex with men (MSM) in Xi' an city.Methods 5 ml anti-coagulating blood samples were collected from MSM who had been reported during 2010-2012 in Xi'an.Both gag and env genes were amplified by nested RT-PCR from the extracted RNA and then sequenced.The acquired sequences were compared with international subtype references,and then the genetic distances were calculated and phylogenetic trees were constructed by Mega 5.2.Epidemiological information including sexual behavior characteristics,history of drug use,blood donation,etc.were gathered.Results 168 samples were successfully amplified and sequenced.Results from Phylogenic analysis showed that the gag and env sequences of 165 samples shared the same subtypes,of which 79 (47.0％) were CRF01_AE,74 (44.0％) were CRF07_BC and 12 (7.1％) belonged to subtype B.There were 3 samples with gag and env sequences classified into different subtypes,of which 2 (1.2％) were CRF01_AE/A1,and the other 1 was CRF07_BC/CRF01_AE.Conclusion At least three HIV-1 subtypes including CRF01_AE,CRF07_BC were identified among MSM population in Xi'an city.