10.3969/j.issn.2095-4344.2013.23.018

In order to set up a base for stem cells to be widely used in clinical medicine, we tried to optimize, in this study, the technique that induces human mesenchymal stem cells (hMSCs) to differentiate into neural stem cells by using cerebrospinal fluid (CSF) from the different groups. After the induction, presence of neural stem cells was confirmed with microscope observation, flow cytometry analysis, immunohistochemistry and fluorescent immunohistochemistry. At the same time, we also compared and analysed the data of the number of stem cells when it totally met the requirements for clinical treatment and the days required. At last, we confirmed that hMSCs could be induced to differentiate into neural stem cells, and that the number of cells totally met the requirements for clinical treatment. But there were some differences both in the number of cells and the days required. Among the groups, the group that marrow mesenchymal stem cells from patients own induced by CSF from healthy volunteers used the shortest time and the quantity of the cells was significantly higher than those of the others.
Cell Differentiation ; Cerebrospinal Fluid ; chemistry ; Culture Media ; chemistry ; Flow Cytometry ; Humans ; Immunohistochemistry ; Mesenchymal Stromal Cells ; cytology ; Neural Stem Cells ; cytology

Child, Preschool ; China ; epidemiology ; Enterovirus A, Human ; genetics ; Female ; Hand, Foot and Mouth Disease ; epidemiology ; Humans ; Infant ; Male ; Molecular Epidemiology

Objective To understand the molecular epidemiology of norovirus from 5 outbreaks of gastroenteritis during Dec.2012 to Jan.2013 in Guangzhou.Methods Epidemiologic data and specimens were collected from 5 gastroenteritis outbreaks in Guangzhou.274 specimens were detected for norovirus by RT-PCR methods and PCR products were sequenced.Sequence alignment and phylogenetic analysis were performed by using Clustal X 1.83 and MEGA 5.05 programs.Statistical analysis was performed by using SPSS 17.0 program.Results The total positive rate of norovirus was 20.07％ (55/274).The positive rate was 8.70％ (2/23) in University A,36.36％ (8/22) in Kindergarten B,36.07％ (22/61) in University C,100％ (5/5) in community health service center D,11.04％ (18/163) in University E.The positive rate was 100％ (6/6) among age group ≥ 60 years old,47.37％ (9/19) among 10-19 age group and 36.36％ (8/22) among age group ＜ 10 years old.Phylogenetic analysis showed that 33 samples were infected by the new variant-Sydney 2012 of norovirus GⅡ.4.Conclusion Norovirus was one of the main pathogens causing acute gastroenteritis outbreaks and GⅡ.4 Sydney 2012 variant was identified as the predominant strain in Guangzhou.

Objective:To investigate the pathogenic spectrum of hand, foot and mouth disease(HFMD)from 2017 to 2019 in Guangzhou, and analyze molecular epidemiological characteristics of coxsackievirus A6 (CV-A6).Methods:Enterovirus A71 (EV-A71), CV-A16, CV-A6 and enterovirus were tested by reverse transcription-quantitative polymerase chain reaction(RT-qPCR). The CV-A6 representative samples were isolated and the VP1 region of isolates were amplified and analized by Mega5.0 and SeqMen.Results:A total of 7 578 enterovirus-positive specimens were detected from 2017 to 2019, 320 specimens were positive for EV-A71, 1481 specimens were positive for CV-A16, 3171specimens were positive for CV-A6, and 2606 specimens were positive for other enterovirus. Children under the age of 5 years were the most vulnerable population, and the male/female incidence ratio was 1.56∶ 1.The incidence occurred in all seasons, one peak between May and July, the other between September and November. The virus was isolated from 80 CV-A6 positive specimens and the full length of VP1 gene region was sequenced and nucleotide sequence similarity analysis was performed. The nucleotide homology in the VP1 region was 93%-100%, and the amino acid homology was 98%-100%. The nucleotide homology with the CV-A6 prototype strain (Gdula) VP1 region was 79%-81%, and the amino acid homology was 95%-97%. The nucleotide homology with the representative strain of D3 subtype was 92%-98%, and the amino acid homology was 98%-100%. Phylogenetic tree shows that all CV-A6 belonged to the sub-genotype D3 and distributed in multiple branches.Conclusions:CV-A6 is emerging as one of the major pathogen causing HFMD in Guangzhou, and all insolates belonged to D3 subtype. Closely monitoring the molecular characteristics of CV-A6 and changes in the pathogen spectrum can provide scientific basis for HFMD prevention and control.

OBJECTIVETo identify the enterovirus from stool samples of patients with hand, foot and mouth disease(HFMD) in Guangzhou from 2010 to 2012 and to perform phylogenetic analysis of the VP1 gene sequences of coxsackievirus A4 and coxsackievirus A10.

METHODSA total of 5 484 samples of suspected cases of HFMD which Guangzhou Center for Disease Control received from 2010 to 2012 were collected.Virus RNA was tested by nested RT-PCR method as human enterovirus 71, coxsackievirus A16, coxsackievirus A4, coxsackievirus A10 and other enteroviruses positive, and 4 111 samples were positive. Phylogenetic tree was constructed by partial VP1 gene sequences of coxsackievirus A4 and coxsackievirus A10 to perform phylogenetic analysis.

RESULTSIn 4 111 enterovirus-positive samples, the positive rate of EV71, CoxA16, CoxA10 and CoxA4 was 35.1% (1 443/4 111) , 30.7% (1 261/4 111) , 2.0% (82/4 111),0.8% (31/4 111) respectively. Different enterovirus-positive rate was statistically significant (χ(2) = 148.34, P < 0.05) .Incidences of coxsackievirus A4 positive was highest in 3-year old children as 1.3% (7/534) , and that of coxsackievirus A10 positive was highest in 0-year old children as 3.7% (34/914) . The highest positive rate of diagnosed coxsackievirus A4 positive cases was admitted in April(2.6%, 12/460) , and the highest positive rate of diagnosed coxsackievirus A10 positive cases was admitted in August 4.3% (12/278). Phylogenetic analysis indicated that all the CoxA4 stains were divided into subtype A and subtype B, and the CoxA10 stains were divided into subtypes A, subtype B and subtype C. The VP1 gene nucleotide sequences of CoxA4 and CoxA10 this study measured both belonged to subtype A.

CONCLUSIONSThe VP1 gene nucleotide sequences of CoxA4 and CoxA10 in Guangzhou from 2010 to 2012 both belonged to subtype A.

Child ; China ; epidemiology ; Enterovirus A, Human ; Hand, Foot and Mouth Disease ; Humans ; Molecular Epidemiology ; Phylogeny ; Polymerase Chain Reaction ; RNA, Viral

Objective: To find out the source and the epidemic pattern of norovirus outbreak in July, 2016 to June, 2017 in Guangzhou. Methods: The stool samples and clinical information of diarrhea cases were collected by the sentinel hospitals and CDCs; a real-time RT-PCR method was used to detect the norovirus nucleic acids from the samples, the positive ones were amplified and sequenced; the partial sequences of norovirus were aligned by an online BLAST alignment, and a phylogenetic tree was constructed by a neighbor-joining method . Results: A total of 854 cases with infectious diarrhea were reported by Guangzhou diarrhea surveillance network from July, 2016 to June, 2017; the gender ratio (male versus female) was 1∶0.67; 78.33% of the cases were preschool children under the age of 7 years. Totally 220 samples were detected norovirus G II+ (25.76%, including 5 double-positive samples with G I+ ). GII.Pe-GII.4.Sydney_2012 was the prevalent genotype in the second half of 2016 (94.64%), which was replaced by GII.P16-GII.2 in the first half of 2017 (67.65%). Since September 2016, the reported number of norovirus-caused diarrhea epidemic was increased gradually; the peak of epidemic curve emerged in February to March of 2017, and the number started to decrease since April. In May to June there were only 2-3 epidemics reported monthly. All the endemics from September to November 2016 were caused by genotype GII.Pe-GII.4.Sydney_2012; the endemics from December 2016 to April 2017 were mainly caused by genotype GII.P16-GII.2. Some samples from kitchen workers and babysitters were detected GII+ , which was consistent with the result of the cases′ samples. Conclusions It was the first time that the novel GII.P16-GII.2 recombinant strain outbroke occurred in Guangzhou City and homology analysis also suggested that GII.P16-GII.2 was the main source of those epidemics in 2016 -2017 winter and spring season. Furthermore, The kitchen workers and babysitters may have played an important role in the spread of norovirus.