The emergence of novel GII.4 norovirus variant, Sydney_2012, in Shanghai, China / 病毒学报

To describe the epidemiological characteristics of norovirus (NOV) associated acute gastroenteritis in Shanghai and characterize the evolution pattern of circulating strains. From March 2012 to February 2013, 502 stool specimens were collected from adult (> or = 16 years) outpatients who visited either of the two sentinel hospitals in Shanghai for acute gastroenteritis. Molecular detection and genotyping of NoV were performed and the phylogenetic relationship of the circulating strains has also been comprehensively analyzed. The epidemics level of GI NoV was low throughout the surveillance period, with the positive rate of 3.78% (19 cases), and no seasonality of GI NoV infection could be distinguished. For GII genogroup, higher epidemics in adults in Shanghai, with the detection rate of 17.13% (86 cases), were observed. And relatively high epidemics of GII NoV infection were spotted between October and December in 2012. The frequency of NoV associated acute gastroenteritis in older people is significantly higher than that in young individuals (P < 0.05). Sequencing and genotyping analysis revealed that the high epidemics of GII NoV infection between October and December in 2012 is associated with the emergence of a novel GII.4 norovirus strain, termed Sydney_2012. Sequence analysis also demonstrated that this was a recombinant virus between a GII.e polymerase and GII.4 capsid, which has also been the dominant circulating strain in Shanghai. In 2012, a new GII.4 variant, termed Sydney_2012, emerged in Shanghai and caused high epidemics of acute gastroenteritis during late autumn and winter.

Construction of full-length complementary DNA of hepatitis C virus genome from an HCV infected patient / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To construct the full-length complementary DNA of HCV genome from an HCV infected patient.</p><p><b>METHODS</b>Four HCV gene fragments (1.6, 3.5, 2.4 kb and 2.6 kb) were amplified by RT-PCR from serum of a Chinese patient and fused and connected together to produce a 9.2 kb subgenomic fragment, which was further cloned into a cassette vector with fixed 5-prime and 3-prime termini of HCV to make the full-length cDNA. The cDNA heterogeneity was analyzed by comparing the sequences of 4 isolated HVR1 regions. The prokaryotic expressed Core, NS3 protease, NS3 helicase were detected for their specific reactivities with patient serum by Western blot analysis. And the protease activity of NS3 was evaluated in a cell-based NS3/4A-SEAP expression system.</p><p><b>RESULTS</b>The cDNA covered the near full-length of HCV genome from the patient's serum. The difference among HVR1 regions indicated no selection of HCV variants during RT-PCR and the quasi-species characteristic of the amplified cDNA. The prokaryotic expressed viral proteins could be identified by patient serum. In the NS3/4A-SEAP system, NS3 could cleave the 4A-4B site between NS4A and SEAP proteins and resulted in the secretion of SEAP in culture media.</p><p><b>CONCLUSION</b>These results suggest that the cloned HCV cDNA encodes a complete and functional open reading frame and will be useful for further construction of infectious cDNA clone.</p>

Determination and analysis of multi- bacteria coinfection of acute pneumonia / 实用儿科临床杂志

Objective To investigate the proportion of streptococus pneumonia(SP), haemophilus influenzae (Hi),branhamella catarrhalis (BC), chlamydia pneumonia (CP) and mycoplasma pneumonia (MP) in children with acute pneumonia.Methods Fifty-three hospital-treated children with acute pneumofmonia were included in a prospective study. The enzyme immunoassay was used to detect antibodies in paired sera against non-capsulated Hi, Hi type-B capsular polysaccharide and whole cell, antibodies against pneumococcal pneumolysin, C-polysaccharide and pneumococcal pneumolysin, C-polysaccharide, surface protein A in circulating immune complexes and antibodies against BC and MP. Antibodies against CP by immunofluorescence in paired sera as well as blood cultures were detected in these cases.Results The evidence of bacteria infection was demonstrated in 32 cases (60.4 %) among children with acute pneumonia, of which 11 cases had 2 or 3 organisms coinfection. In these causative agents,SP and CP were the most common organisms (11/53 cases respectively,20.8 %), followed by MP (7/42,16.7 %),Hi(7/53,13.2 %).Conclusion SP,Hi,CP and MP are common causative agents of children with acute pneumonia and multi-agents coinfection isn′t ingnored in our empiric antibiotic therapy for the disease.