Simultaneous determination of 12 ß-agonists in feeds by ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry.

A new analysis method using ultra-performance liquid chromatography (UPLC)-quadrupole-time-of-flight mass spectrometry (Q/TOF MS) was developed for screening and confirmation of 12 ß-agonists in feeds. Under the optimized gradient elution conditions, it takes only 6 min to separate all 12 ß-agonists, and the critical pair of Ractopamine and Isoxsuprine isomers was almost completely separated. Based on the over 10,000 full-width at half maximum (FWHM) mass resolution and high mass accuracy features of TOF MS with 20 mDa mass window, accurate mass chromatograms were reconstructed for individual compounds. The fragmentation pathways of 12 ß-agonists were also studied using Q-TOF MS. The potential of UPLC-Q/TOF MS for confirmatory analysis was shown by determining the accurate mass of all compounds and fragment ions upon collision-induced-dissociation (CID) at different energies. The extra mass measurement errors for all ß-agonists were found to be within 5 ppm. The limits of detection (LODs) and limits of quantitation (LOQs) were determined for all ß-agonists in feeds and found to be 1-5 ng/mL and 5-50 µg/kg, respectively. The method of UPLC-Q/TOF MS developed in this study was initially applied to the research of feeds for analysis of 12 ß-agonists and proved to be accurate, sensitive, convenient and practical.

Subtype and sequence analysis of the gag genes for HIV-1 strains isolated in Hubei province / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the characteristic of subtypes and genetic diversity of HIV-1 circulating in Hubei province and its molecular epidemiological linkages with regard to risk factors of viral transmission.</p><p><b>METHODS</b>plasma samples of 80 diagnosed individuals was characterized. The gene fragments of gag were amplified by reverse transcriptase polymerase chain reaction (RT-PCR) and HIV-1 genotypes were determined based on the nucleotide sequences of gag region.</p><p><b>RESULTS</b>Seven HIV-1 group M subtypes or CRF including B, B', G, CRF01-AE, CRF07-BC, CRF08-BC and CRF15-01B were identified. CRF01-AE was found to be the most dominant subtype (48.4%) followed by CRF7-BC (22.6%) and B' (12.9%).</p><p><b>CONCLUSION</b>The data from this study indicate the existence of multiple HIV-1 subtypes or CRFs in Hubei province and the surveillance of HIV-1 gene variation should be paid more attention to.</p>

Expression and subcellular localization of APOBEC3G in peripheral blood mononuclear cells and liver tissues of chronic HBV patients / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the expression level and intracellular localization of APOBEC3G in peripheral blood mononuclear cells (PBMCs) and liver tissues of chronic HBV patients.</p><p><b>METHODS</b>The expression level and intracellular localization of APOBEC3G in PBMCs and liver tissues were detected using the western blot and confocal laser scanning microscope (CLSM).</p><p><b>RESULTS</b>Western-blot showed that the expression level of APOBEC3G in PBMCs of healthy controls was very low. The relative expression levels of APOBEC3G in PBMC of patients with chronic hepatitis B, chronic severe hepatitis, liver cirrhosis, or liver cancer were 4.12+/-0.21, 4.07+/-0.28, 4.16+/-0.36 or 4.21+/-0.39 respectively, which were higher than that in the healthy controls. However, there was no significant difference in APOBEC3G expression among different chronic HBV patients (q = 0.931, 0.744, 1.675, 1.675, 2.606 or 0.931, respectively, all P values more than 0.05). In addition, there was no significant difference on APOBEC3G in liver tissues between chronic hepatitis B patients and hepatocellular carcinoma patients (4.40+/-0.34 vs 4.34+/-0.43, q = 0.588, P more than 0.05). CLSM indicated that the localization of APOBEC3G protein was in cytoplasm of PBMCs and hepatocytes.</p><p><b>CONCLUSION</b>APOBEC3G is upregulated in the PBMCs of chronic hepatitis B patients.</p>

Study on molecular epidemiology of people infected with human immunodeficiency virus-1 in Hubei province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the distribution of human immunodeficiency virus-1 (HIV-1) genotypes in Hubei province.</p><p><b>METHODS</b>Epidemiological survey was carried out to HIV-1 carriers who were identified in Hubei province. HIV-1 env V3-V4, gag P17/24 and the first exon of tat region were amplified by nested-polymerase chain reaction(nPCR) .The sequences were determined, and phylogenetic analyses were then performed.</p><p><b>RESULTS</b>4 HIV-1 strains or circulating recombinant forms (CRFs) were identified in Hubei province with subtype B' the predominant which covered 5 kinds of populations including former blood donors, blood receivers, spouses of the infected people, sex workers and their clients, homosexuals, mainly distributed in the areas with many former blood donors. CRF08-BC and CRF01-AE were found distributed in economically more developed cities or southern area of the province, and the major transmission routes was through sexual contact. Only 1 patient, an injecting drug user, was identified having subtype C.</p><p><b>CONCLUSION</b>Subtype B' was the main epidemic subtypes in Hubei province while CRF08-BC, CRF01-AE and subtype C were also circulating in the province, indicating the transmission of the disease might to become more complex.</p>