OBJECTIVETo analyze the phenotype-genotype correlation of MYH7-V878A mutation.

METHODSExonic amplification and high-throughput sequencing of 96-cardiovascular disease-related genes were carried out on probands from 210 pedigrees affected with hypertrophic cardiomyopathy (HCM). For the probands, their family members, and 300 healthy volunteers, the identified MYH7-V878A mutation was verified by Sanger sequencing. Information of the HCM patients and their family members, including clinical data, physical examination, echocardiography (UCG), electrocardiography (ECG), and conserved sequence of the mutation among various species were analyzed.

RESULTSA MYH7-V878A mutation was detected in five HCM pedigrees containing 31 family members. Fourteen members have carried the mutation, among whom 11 were diagnosed with HCM, while 3 did not meet the diagnostic criteria. Some of the fourteen members also carried other mutations. Family members not carrying the mutation had normal UCG and ECG. No MYH7-V878A mutation was found among the 300 healthy volunteers. Analysis of sequence conservation showed that the amino acid is located in highly conserved regions among various species.

CONCLUSIONMYH7-V878A is a hot spot among ethnic Han Chinese with a high penetrance. Functional analysis of the conserved sequences suggested that the mutation may cause significant alteration of the function. MYH7-V878A has a significant value for the early diagnosis of HCM.

Adult ; Amino Acid Sequence ; Asian Continental Ancestry Group ; genetics ; Cardiac Myosins ; genetics ; Cardiomyopathy, Hypertrophic ; genetics ; Female ; Genetic Association Studies ; methods ; Genotype ; Humans ; Male ; Middle Aged ; Mutation ; genetics ; Myosin Heavy Chains ; genetics ; Pedigree ; Phenotype ; Young Adult

Objective To test the levels of enterovirus 71 (EV71) antibody among children of different ages in Shanghai in 2011,and to investigate the relationship between antibody levels and virus infection.Methods EV71 antibody was detected by microneutralization assay from the serum specimens of healthy children of different ages collected during July to August,2011.The results were analyzed by t test for quantitative data with normal distribution,and by x2 test for count data.Results The positive rate of EV71 antibody among the 93 serum specimens was 58.1％ (54/93).The geometric mean titer (GMT) of EV71-specific neutralizing antibody was 1 ∶ 14.48.The positive rate of EV71 antibody in infants less than 6 months old was 87.5％ (21/24),and the GMT was 1∶29.56.In children aged 2 to 3 years,the positive rate of EV71 antibody decreased to 3.7％ (1/27),and GMT decreased to 1∶4.21,which were both statistically significantly lower than those less than 6 months old (x2 =36.37,t=7.58; both P＜0.01).The positive rate of EV71 antibody increased to 83.3％ (20/24) in children aged 5 to 6 years,with GMT reaching 1∶21.74.Whereas in children aged 7 to 8 years,the positive rate was 66.7％ (12/18) and GMT was 1∶20.76,without statistically significant difference compared with those aged 5 to 6 years (x2 =1.58,t=0.597; both P＞0.05).No statistically significant difference was found between boys and girls in positive rate of EV71 antibody [62.7 ％ (32/51) vs 52.4 ％ (22/42),x2 =1.02,P＞0.05] or GMT (1 ∶ 16.23 vs 1 ∶ 12.61,t=0.881,P＞0.05).Conclusions Children aged 2 to 3 years were at higher risk for EV71 infection,with EV71 antibody level significantly lower than other age groups.

Objective To analyze the VP1 and VP4 genetic region of enterovirus 71 (EV71)isolated from severe cases and mild cases with hanD-foot-mouth disease (HFMD) in Shanghai in 2011.Methods Five EV71 strains isolated from severe cases and five EV71 strains from mild cases in 2011 were included.Reverse transcription-polymerase chain reaction (RT-PCR) method was used to amplify and sequence the VP1 and VP4 genes of EV71,and then the sequencing results were compared with those of A,B,C genotype reference EV71 strains from GenBank by nucleotide alignment,amino acid alignment and phylogenetic tree analyses.Results The homogeneity between EV71 strains from severe cases and mild cases was 96.0％-98.1％ and 93.7％-99.5％ for VP1 and VP4 nucleotide sequences,respectively.The VP1 nucleotide sequences of 5 strains isolated from severe cases and 5 strains from mild cases in Shanghai shared 86.9％-98.2％ and 87.4％ 98.5％ identity with genotype C,respectively,while the homogeneity of VP4 nucleotide sequence was 85.5％-100.0％and 84.5％-99.5％,respectively.In addition,compared with the Fuyang EV71 strains (representative of C4 subtype),the strains from mild and severe cases shared homogeneity of 97.0％-98.2％ and 97.9％-98.5％ for VP1 gene,respectively,96.1％-100.0％ and 97.1％-99.5％ for VP4 gene,respectively.Among 3 strains isolated from severe cases,mutations at the residue 282 in the VP1 protein (N→S) and residue 7 in the VP4 protein (T→A) were discovered simultaneously.Conclusions The 10 EV71 strains isolated from severe and mild cases in Shanghai belong to subgenogroup C4.Among 3 strains isolated from severe cases,mutations at the residue 282 in the VP1 protein (N→S) and residue 7 in the VP4 protein(T→A) are discovered simultaneously.

Objective To evaluate shell vials of MHV,a combination of Madin-Darby canine kidney cells (MDCK),human epidermoid cancer cells (Hep-2) and African green monkey kidney cells (Vero),and conventional cell culture in detecting influenza viruses and enterovirus from fresh clinical specimens.Methods Specimens from patients with influenza-like illness and children with hand-foot-mouth disease were inoculated with both shell vials of MHV and MDCK/Vero.Then cytopathological effect (CPE) was examined daily.Influenza viruses and enteroviruses were detected by multiple reverse transcriptase-polymerase chain reaction (mRT-PCR).Results CPE of MDCK/Vero cells were stronger than the shell vials of MHV.The isolation rate of influenza virus by MHV was 24.6％ (34/138) and that by MDCK was 28.3％ (39/138),which was not significantly different (x2 =1.92,P＞0.05).That of enterovirus by MHV was 28.1％ (9/32) and that by Vero was 37.5％ (12/32),which was not significantly different (x2 =3.00.P＞0.05).Conclusions CPE in MDCK/Vero cells are easier to be observed than the shell vials of MHV.However,the shell vials of MHV are appropriate in public health emergencies,which can be used for isolation of influenza viruses and enterovirus in patients with respiratory symptoms.

Objective To understand the genetic and antigenic variations of influenza A (H1N1) isolates in Shanghai area in winter of 2010.Methods A total of 137 throat swabs were collected from patients with influenza-like illness in the sentinel hospital in Shanghai area from December 2010 to January 2011,then inoculated into Madin-Darby canine kidney (MDCK) cells.The types of influenza were identified by direct immunofluorescence assay (DIF) and influenza A (H1N1) subtype was determined by reverse transcriptase-polymerase chain reaction (RT-PCR).The mutations of gene and amino acid locus were analyzed through the whole genome sequencing of hemagglutinin (HA),neuraminidase (NA) and polymerase (PB2) segments from some influenza A (H1N1) isolates.Results Total of 53 human influenza virus strains were isolated including 48 influenza A (H1N1) virus strains.Nineteen strains were selected for sequencing by simple random sampling.The phylogenetic tree of HA gene revealed that the latest isolates and most of influenza A (H1N1) viruses isolated before June 2010 were not in the same stem.Analysis of amino acid residues in HA protein showed that mutations were found in antigenic determinant region in some strains.Residues at the enzyme active sites of NA protein were strictly conservative,no change was observed in amino acid residues which were related to drug resistance against oseltamivir and zanamivir.The 627 and 701 residues in PB2 protein were glutamic acid and aspartic acid,respectively,which was still the feature of avian influenza virus,but E677G mutation was detected.Conclusion Compared to influenza A (H1N1) strains isolated in spring and summer,some variations have been detected in the strains isolated in Shanghai area in winter of 2010,some antigen drift and adaptive evolution in mammalian hosts have appeared.

Objective To evaluate the survival ability of enterovirus 71 (EV71) on different surface and under different climate.Methods Each 1 × 105 tissue culture infective dose 50 (TCID50)EV71 was added on different aseptic surface of plastic,rubber,cloth and wood,respectively.Then these materials were put into biotron (artificial climatic chamber) which could simulate different temperature and moisture.The viruses were recovered after a definite time and then inoculated into Vero cell.The cytopathic effect (CPE) was observed everyday to survey the survival ability of EV71 on different medium surface.Results The recovery rates of EV71 on medium surface ranged from 89 ％-93 ％.The survival time of EV71 on medium surface varied under different climatic conditions.The longest survival time of the virus was observed under the condition of 20 ℃ as the temperature and 80％ as the humidity.After 24 hours of incubation,the infectious titer on plastic surface reduced about 4 lg.After 72 hours of incubation,the infectious titer reduced at least 3.89 lg on cloth and wood surface.Conclusions Temperature and humidity can affect the survival time of EV71 on medium surface,which is longer in the condition of low temperature and high humidity.The survival ability of EV71 on natural cloth and wood surface is better than that on synthetic plastic surface.

Objective To establish a clinical test assay for detecting common respiratory viruses and enteroviruses (EV) by using mixed cultured Madin-Darby canine kidney cells (MDCK), human epidermoid cancer cells (Hep-2) and African green monkey kidney cells (Vero) to isolate common respiratory viruses and enteroviruses. Methods Throat swabs with influenza A and B viruses,adenovirus and EV71 were incubated with mixed cultured MDCK, Hep-2 and Vero in a single vial to observe the presence of cytopathic effects. Polymerase chain reaction (PCR), reverse transcription (RT)-PCR and monoclonal antibody-based immunofluorescene assay were also used for confirmatory test. Results The sensitive cell lines developed obvious cytopathic effects to the corresponding viruses, which were confirmed by the specific green particles observed by immunofluorescence assay and specific target PCR segments. Conclusions The shell-vial of mixed cells can simultaneously isolate different common respiratory viruses and EV. The isolated pathogens can be further confirmed by antigen test and PCR. This assay may improve the diagnosis of clinical viral diseases.

Objective To study the gene characteristics of VP1 region of Enterovirus 71 (EV71) strains isolated from clinical specimens of children with hand-foot-and-mouth disease(HFMD) in Shanghai in 2010.MethodsEighteen EV71 isolates were selected from different periods of year 2010,including strains isolated from fatal cases and non-fatal cases.Complete VP1 gene (891nucleotides) of the eighteen EV71 isolates were amplified and sequenced,and then compared with that of genotype A,B,C reference EV71 strains in GeneBank by homogeneity and phylogenetic tree analyses.ResultsThe nucleotide homogeneities between these 18 Shanghai strains and the representative isolates of genotype A and B were 81.5 ％ -82.6 ％ and 83.4 ％- 84.2 ％,respectively,while the amino acid homogeneities were 94.3 ％- 95.0％ and 96.6％ -97.0％,respectively.The nucleotide and amino acid homogeneities between the 18 Shanghai strains and the representative isolates of genotype C were 87.4％- 99.2％ and 98.7％ -100.0％,respectively.Of note,the nucleotide and amino acid homogeneities between Shanghai strains and Fuyang EV71strains (representative strain of C4 subtype) appeared to be 97.8％- 99.2％ and 99.3％- 100.0％,respectively.The eighteen EV71 Shanghai strains were classified as genotype C,subgenogroup C4 in the phylogenetic tree.There was no remarkable difference in VP1 gene between the strains isolated from fatal cases and non-fatal cases.ConclusionThe EV71 strains isolated from Shanghai belong to subgenogroup C4.

Objective To evaluate the survivability of hand foot mouth disease(HFMD)virus,in tap water for daily use.Methods HFMD viruses were isolated from cases of HFMD in Shanghai and Zhejiang from in 2008.Six isolated strains (five subtype of enterovirus 71 and one coxackie virus)were selected in this study.These viruses were mixed with chloride 1.0 mg/L tap-water and then inoculated into Vero cells.The cytopathic effect (CPE)was checked everyday in order to survey the survivability of each virus strain.The decline of virus survivability was analyzed by scatter diagram.Results These six strains of HMFD virus could survive longer than one month in tap water with initial chloride concentration of 1.0 mg/L and still had celluar infectivity.The survivabilities were varied between viruses isolated from different HFMD cases.Conclusions The survivabilities of enterovirus 71 and coxackie virus stains are quite strong in water.Therefore,the transmission route of water-borne pathogens should be monitored in regions using tap water during HFMD epidemic period.

Objective To know the levels of antibodies against influenza A virus subtypes H1 and H3 of population in Shanghai during 2009, and the detection of antibodies against avian influenza virus subtypes H5 and H9 in population which contacts with avian. Methods The serological survey of the antibodies against influenza A viruses subtypes H1, H3, H5 and H9 in 356 close contacts with avian (professional population) and 332 general subjects (general population) at various age groups were carried out using hemagglutinin inhibit (HI) test. Results The positive rates of antibodies against influenza virus A/Brisbane/59/2007 (H1N1) in general population and professional population were 82.8% (275/332) and 73.9% (263/356), respectively; those of A/Brisbane/10/2007 (H3N2)were 50.6% (168/332) and 54.8% (195/356), respectively. The positive rate of antibodies against influenza virus A/Brisbane/59/2007 (H1N1 )was significantly higher than that of influenza A viruses subtype H3, which was consistent with etiological survey of influenza virus in Shanghai during 2008.The positive rates of antibodies against influenza A virus subtype H5 in professional population and general population were 4.2% (15/356) and 0.3% (1/332), respectively; those of influenza A virus subtype H9 were 34.6% (123/356) and 2.4% (8/332), respectively. The positive rates of antibodies against influenza virus A/Brisbane/59/2007 (H1N1 ) and A/Brisbane/10/2007 (H3N2) in age groups of 6 months-5 years and ≥60 years were lower than other age groups. Conclusions The immune protective response against seasonal influenza A subtype H1 and H3 of population in Shanghai is high,while those of children and the elders were low. The levels of antibodies against influenza A viruses subtype H5 and H9 in professinal population present obviously ascending trend, which indicates that the etiological and serological survey of influenza virus in this population should be enhanced.