Human bocavirus and its current epidemic status in China / 病毒学报

Human bocavirus (HBoV) is classified in the family of parvovirdae, genus bocavirus. Besides parvovirus B19 and human parvovirus 4 (PARV4), HBoV isone of the parvoviruses currently known to infect and cause illness in human. So far, four different HBoVs (HBoV1-4) have been successively reported. The incidence of HBoVs infection varies widely, the clinical presentations of patients are different, and HBoVs are often co-detected with other pathogens. There are already quite a few report of HBoVs infection, and this article reviews and discusses the biological characters, epidemic characters, pathogenic mechanism, phylogenetic analyses of HBoVs and the epidemiological situation in China.

Recombination analysis of enterovirus 71 strain isolated in Guangzhou, 2009 / 病毒学报

To describe the recombination features of human enterovirus 71 strain Guangzhou09 isolated in Guangzhou in 2009, the complete nucleotide sequences of Guangzhou09 were analyzed by various of bioinformatics software. Phylogenetic analysis based on P1, P2 and P3 regions indicated that recombination occurred between EV71 and CVA4. Phylogenetic, similarity plot and bootscan analysis further revealed the recombination between EV71 genotype C strain Shanghai-FJ713317 and CVA4 strain HQ728260 at region 2B was close to the nucleotide position 4 027. This represents the first evidence for intertypic recombination between EV71 subtype C4 and CVA4 in Guangzhou.

Variation and evolution analysis of the PB1-F2 genes of novel influenza A viruses isolated from Guangzhou China / 病毒学报

To compare and analyze the variation of PB1-F2 genes of Influenza A Viruses from Guangzhou during 2009 to 2011 with the Influenza A Viruses from all over the world, to lay the foundation of functional research and interaction mechanism of the PB1-F2 protein. 17 Novel H1N1 influenza viruses and 1 seasonal H1N1 influenza virus have been isolated from human in Guangzhou during 2009 to 2011 that were cloned into pMD 18-T Vector for sequencing. Then, 68 PB1-F2 genes of IAVs from human around the world were downloaded from GenBank database and analyzed using molecular biological software. The phylogenetic tree result shows that the PB1-F2 genes of IAV from the world separated into two main groups. There is high homology of PB1-F2 genes of one Seasonal H1N1 virus and Novel H1N1 viruses which were isolated in Guangzhou compared with the global Novel H1N1 viruses. And all of them got the 11 amino acids truncated protein by mutation included one seasonal H1N1 strain isolated by our laboratory. There is no variation of PB1-F2 genes of Novel H1N1 virus in Guangzhou compared with the worldwide strains. However, one seasonal H1N1 virus which isolated by our laboratory shows analogous truncated mutation of PB1-F2 of Novel H1N1 virus, it reveals that the PB1-F2 gene might has done the early reassortment between the Novel H1N1 virus and seasonal H1N1 virus.

Optimal in vitro culture conditions for murine predominant immature CD8a+ dendritic cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The prospects of using immature CD8a(+) dendritic cells (DC2) to establish transplant immunologic tolerance and treatments for autoimmune diseases in the future are promising. However, the methods for inducing DC2 are still being explored. The present study was aimed to investigate the optimal in vitro conditions for preparing large numbers of predominant DC2 from murine bone marrow cells.</p><p><b>METHODS</b>Three groups of bone marrow cells cultured under different conditions were examined, namely a cytokine-induced experimental group (cytokine group), a control group with a low concentration of granulocyte-macrophage colony stimulating factor (GM-CSF, low GM-CSF group) and a control group without endogenous cytokines. The cytokine group was cultured with 5 ng/ml GM-CSF, 25 ng/ml Flt3 ligand (Flt3L), 20 ng/ml interleukin 4 (IL-4) and 100 ng/ml stem cell factor (SCF). The low GM-CSF control group was cultured with 0.4 ng/ml GM-CSF, 25 ng/ml Flt3L and 100 ng/ml SCF, without IL-4. The control group without exogenous cytokines was cultured without additional cytokines. All cells were cultured at 37 degrees C under 5% CO2. On days 3, 7 and 16, 4-color flow cytometry was carried out to analyze the cell phenotypes, and the total cell numbers were counted to analyze the cell yields. Phase-contrast microscopy was used to observe the cell morphologies.</p><p><b>RESULTS</b>The cytokine group exhibited higher proportions of typical immature CD8a(+) DC, especially on day 3, but the total cell number and DC2 proportion decreased during prolonged culture. The low GM-CSF control group showed the same tendencies as the cytokine group on days 16 and 22, but produced higher total cell numbers (P<0.05) with lower DC2 proportions and cell numbers. The control group without exogenous cytokines spontaneously generated a certain proportion of DC2, but with low total cell and DC2 numbers that decreased rapidly, especially during prolonged culture (days 7 and 16, P<0.05).</p><p><b>CONCLUSIONS</b>Culture in the presence of 5 ng/ml GM-CSF, 25 ng/ml Flt3L, 20 ng/ml IL-4 and 100 ng/ml SCF can rapidly induce large quantities of predominant immature CD8a(+) DC from murine bone marrow cells. Therefore, these represent optimal culture conditions for preparing murine immature DC2 in vitro.</p>

The effect of cell killing and apoptosis by human herpes simplex virus- thymidine kinase/ganciclovir system combined with allitride in BIU87 cells / 中华外科杂志

<p><b>OBJECTIVE</b>To study the killing effect of human herpes simplex virus-thymidine kinase/ganciclovir (HSV-TK/GCV) system combined with allitride and the possible apoptosis mechanism in BIU87 cells.</p><p><b>METHODS</b>The cytotoxicity after combination were estimated by theamine blue tetrazolium bromide (MTT). The morphological changes were observed with inverted microscope and in-situ cell apoptosis detection kit. Changes of apoptosis rate and cell cycle were assessed by flow cytometry. B-cell lymphoma-2 (bcl-2), bax, caspase-3 (cysteine aspartate specific proteinase) mRNA changes were detected by reverse transcriptase polymerase chain reaction, and caspase-3 activity was estimated with colorimetry.</p><p><b>RESULTS</b>For combination group, the cell killing rate was raised to 72.50% to compare with 35.00% of GCV and 37.00% of allitride separately and there was a synergistic effect between these two drugs. The cell apoptosis was induced in all three groups and for the combination group the time of S-phase and G(2)-phase arrest were earlier than other two groups. Both drugs could inhibit the expression of bcl-2 and promote the expression and activity of caspase-3.</p><p><b>CONCLUSIONS</b>The combination of HSV-TK/GCV system with allitride can inhibit the proliferation of BIU87 cells congenerously through apoptosis, which may be correlated with S- and G(2)-phase arrest, down-regulation of bcl-2 and increased caspase-3 expression and its activity.</p>