To identify the isolated suspicious strain of Campylobacter jejuni from the blood of bacteremia patient in Guizhou Province ,China ,conventional and molecular techniques (specific mPCR and NAP-mPCR) were used to identify suspi-cious bacteria strains .Results showed that Campylobacter jejuni suspicious colonies were cultured in bacteremia patient blood samples .The strain was identified as Campylobacter jejuni ssp . jejuni by conventional tests and was identified as Campy-lobacter jejuni by genus specific mPCR .Then the strain was classified as Campylobacter jejuni ssp . jejuni by subspecies NAP-mPCR .The strain was identified as Campylobacter jejuni ssp .jejuni isolated from the blood of bacteremia patient and Campylobacter jejuni can be identified subspecies by NAP-mPCR .

Cause of Death ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Hand, Foot and Mouth Disease ; epidemiology ; mortality ; Humans ; Infant ; Male

Objective To master the prevalence of plague and its trend in Guizhou Province,and to analyze the plague monitoring results from 2000 to 2012.Methods The report of infectious disease,the information of plague natural focus and the epizootic monitoring data of Xingyi City,Anlong County and Dingxiao Distract of Guizhou Province from 2000 to 2012 were collected and the status of the plague natural focus was analyzed.Results There were 137 cases of gland plague in Xingyi City and Arlong county from 2000-2003,1 death,and mt plague occurred in 66 villages.Fifty-four strains of Yersiniapestis were detected and 49 rats were plague antigen F1 positive(49/160).No human plague occurred between 2004-2012.A total of 4 plague antigen F1 positive rats were detected in Dingxiao District and Xingyi City in 2005 and 2006.There was no Yersinia pestis and F1 antibody in 2007-2012.The epidemic stage of plague was from 2000-2003; the active stage was from 2004-2006; and the quiescent stage was from 2007-2012.The dominant species of the plague natural focus was Rattus flavipestus (42.83％,7 966/18 597),but was replaced by Rattus norvegicus at the epidemic stage (47.22％,1 480/3 134) and the active stage(35.35％,2 071/5 196).The density of rodents was 5.34％ at the epidemic stage,which was higher than that of the active stage (3.27％) and the quiescent stage (1.71％,x2 =2 286.15,P ＜ 0.01).Xenopsylla cheopis(56.34％,10 034/17 811) was the dominant species,and the index was 1.537 9,which was greater than those of the active stage(0.959 6) and the quiescent stage(0.540 4,x2 =492.68,P ＜ 0.01).Conclusions The plague of Guizhou Province is at the quiescent stage.Both the density of rodents and the Xenopsylla cheopis index are lower than the national standard of controlling.

Objective To evaluate the inhibitory effects of shRNAs targeting genes encoding viral capsomeres VP1-VP4 on enterovirus 71 (EV71) replication when used alone or in combination.Methods Short hairpin RNAs (shRNAs) targeting genes encoding VP1-VP4 protein of EV71 were designed and then respectively inserted into lentiviral vector pLKD-CMV-GFP-U6 to construct the recombinant plasmids.The expression plasmids together with psPAX2 and pMD2.G were transfected into 293T cells to induce the expression of recombinant lentiviruses,which were collected on the third day after transfection.The titers of recombined lentiviruses were determined by real-time PCR.The effects of shRNAs used alone or in combination on the expression of EV71 at mRNA and protein levels were respectively detected by real-time PCR and Western blot.Results The inhibitory effects of shRNAs on EV71 replication showed no significant differences among various strains (isolated from fatal cases,severe cases,mild cases and FY0805) (P＞0.05).Their inhibition rates were 51.6％ (sh-VP1-1),85.1％ (sh-VP1-2),76.4％ (sh-VP1-3),57.5％ (sh-VP2-1),81.4％ (sh-VP2-2),79.5％ (sh-VP2-3),68.9％ (sh-VP3) and 56.7％ (sh-VP4) respectively,and they were in a dosage dependent manner.sh-VP1-2 in combination with sh-VP2-2 showed the highest inhibition rate reaching up to 96.6％.Moreover,shRNAs used in combination showed better effects than any one used alone even at double dosage.Conclusion All shRNAs targeting viral capsid VP1-VP4 genes showed inhibitory effects on EV71 replication with inhibition rates over 50％ and the effects could be strengthened when using shRNAs in combination.

Objective To study the composition of variant and point mutations of Norovirus GⅡ.4 in Guiyang regions.Methods From June to November 2010,cases information and fecal specimens were collected from guard-hospitals in Guiyang regions,who had caught the acute-gastroenteritis.Noroviruses in specimens were detected by a real-time reverse transcription polymerase chain reaction(real-time RT-PCR),and then partial genotyped norovirus-positive clinical samples (in random) were cloned and sequenced in VP1 gene code.Furthermore,the gene sequences were compared with the published variants at home and abroad of norovirus(GⅡ.4),including the phylogenetic analyses of genomes and variation of amino acids within individual sites.Results Those 267 specimens were GⅡ-norovirus-positive(62.68％) in 426 clinical samples.There were nine GⅡ.4-norovirus-positive VP1 gene-sequences available,and two subtype-norovirus variants (GⅡ.4 2008a and G Ⅱ.4 2008b variant) were epidemic in 2010,Guizhou province.The homology between and in subgroups were 95.90％-96.72％ and 99.45％-100％.Two amino acids within individual sites were apt to mutate.Conclusion Norovirus GⅡ genotype were predominant in summer and fall acute gastroenteritis in 2010 for Guiyang regions,and the variants were diversity.

Objective To explore the effect of cryopreserved canine kidney cells (MDCK)single -layer on the isolation and proliferation of influenza virus B.Methods Revived P17 MDCK cells were passage for 2 -4 gener-ations,and subsequently preserved in 4℃ refrigerator for 3,6 and 9 days,respectively.Under same experimental con-ditions,the 4℃ refigerater preserved cells were co -incubated with influenza -like illness(ILI)throat swab speci-mens.Cytopathic effect (CPE)was observed,and the proliferation of virus was determined using real -time PCR and the hemagglutinin titers were determined by serological test.Results (1)CPE:The CPE of the MDCK cells pre-served in 4℃ refrigerator for 3 or 6 days had no significant differences compared with that in the control group,while the cell preserved in 4℃ refrigerator for 9 days showed CPE fastly and maintained for a short time.(2)Real -time PCR:the proliferation of influenza virus B in the MDCK cells preserved with 4℃refrigerator for 3 or 6 days (25.86 × 105 -30.25 ×106 ,26.31 ×105 -30.54 ×106 )had on difference compared with that of the control group (24.82 × 105 -29.86 ×106 ),with the proliferation rate of 105 to 106 times,while the proliferation cell with 4℃ cryopreserved for 9 days(19.72 ×104 -28.34 ×105 )the proliferation in cells preserved for 9 days was sharply decreased,with pro-liferation rate of 104 to 105 times.(3)The HA titer:The virus strains with hemagglutination titer above or equal to 116 (P >0.05)isolated with MDCK cells preserved in 4℃ refrigerator 3 or 6 days were not significantly different from that of the control group (10.92 ±0.79).And the cells with 4℃ cryopreserved for 9 days were significantly dicreased (P <0.01).Conclusion No significant effects on the isolation and proliferation of influenza virus B using MDCK cell preserved in 4℃ frigerator for near one week were observed in the present study.

Eight patients with suspected cases of C .jejuni were etiologically diagnosed and analyzed in this study to pro-vide scientific basis for the confirmation of the cases of human campylobacteriosis in Guizhou Province ,China .Blood or feces of 8 suspected patients were employed to isolate bacteria strains .Conventional and multi-PCR techniques were applied to identify suspicious bacteria strains .The C .jejuni strains were analyzed by using Pulsed Field Gel Electrophoresis (PFGE) .Suspicious strains of C .jejuni were isolated from all the 8 suspected patients of campylobacteriosis and anticipated genes fragment were detected with multi-PCR .With the digestion of restriction enzyme SmaI ,the 8 C .jejuni strains were divided into 7 PFGE pat-terns with 7-10 DNA bands .Cluster analysis showed that the gross similarity of 8 strains of C . jejuni was more than 50% . The similarity of PFGE patterns between strain GZ201004 and GZ201005 from diarrhea patients was as high as 100% ,while the similarity of strain GZ201201 and GZ201007 was 66 .7% .Moreover ,C . jejuni were detected from all the suspected pa-tients of campylobacteriosis .PFGE results indicated that strains GZ201004 and GZ201005 were from the same source ,while all the 8 isolates showed PFGE polymorphism .

To study the characteristic of glycoprotein gene sequence of rabies virus in Guizhou Province in recent years and provide scientific basis for effective control and prevention of rabies,RT-PCR assay were used to detect human and dog brain tissues derived from different prefectures of Guizhou.The amplification products were sequenced and analyzed with bioinformatics software.The results showed that the full-length G gene sequences of 8 positive samples were obtained by RT-PCR amplification,sequencing and splicing.The homology of eight G gene sequences from Guizhou Province were between 87.4％ -99.9％ and 83.3.％- 100％ on nucleotide and deduced amino acid level,respectively,and the highest homology were found with the genotype 1 strains ( 86.5 ％- 87.0％ for nucleotide and 83.3 ％- 100 ％ for amino acid) among genotype 1- 7 representative strains.Besides,phylogenetic analysis based on the G gene indicated that the relationship of 8 strains derived from Guizhou were closest to genotype 1 Lyssavirus,and the strains of Guizhou were very close to the strains come from Hubei,Hunan,Anhui,Guangxi,Jiangsu provinces and Shanghai,except for GZ01 and GZ09.Moreover,GZ09 were evolutionarily closed to the strains come from Malaysia and Thailand,while the remaining sequences were closed to the strain of Indonesia.This study confirmed on the G gene level that rabies virus epidemic strains circulated in Guizhou Province in recent years belonged to rabies virus genotype 1 and the evolutionary relationship with reported strains come from different provinces of China and different countries were revealed in this study.It will provide scientific basis for effective control and prevention of human and animal rabies in Guizhou Province.

Objective To confirm the death of a child injured by a dog was due to rabies and to understand the molecular biologic features of rabies virus in Kaili,Guizhou province.Methods Brain tissue samples of patient and dog were collected to detect the rabies virus by direct immunofluorescence assay (DFA) and RT-nested PCR assay.Homology and phylogenetic tree were analyzed based on the whole nucleotide and deduced amino acid sequence of N gene of rabies virus followed by molecular epidemiological analysis.Results Both the human and dog brain tissue samples were confirmed positive by DFA and RT-nested PCR assay.The homology analysis of N gene sequences among GZH,GZD and other epidemic and vaccine rabies strains isolated from other provinces and other countries indicated that the detected samples shared the highest homology with the strain detected in Anlong prefecture in Guizhou in the year of 2006,and the homology between GZH and GZD was as high as 100％.Besides,among the vaccine strains,GZH and GZD showed the highest homology with strain CNT.Phylogenetic analysis indicated that the two samples were very close and belonged to genetype 1 lyssavirus,with the closest relationship between samples reported in Guizhou and Beijing.Conclusion It was confirmed on the viral molecular level that both the human and dog in Kaili were suffered from rabies,and the pathogens were genetype 1 lyssavirus.The prevalent strains in Kaili city was probably imported from other prefectures of Guizhou province,suggesting that prevention and control measures on rabies in Guizhou province should be strengthened.

Objective To analyze the effects of Leptospira interrogans ( L. interrogans) infection on the activation of NLRP3 in THP-1 and J774A. 1 cells and to further understand the mechanism of inflam-mation caused by L. interrogans in different hosts. Methods Human mononuclear macrophage cell line (THP-1) and murine mononuclear macrophage cell line (J774A. 1) were infected with L. interrogans strain 56601. The expression of NLRP3 at mRNA and protein levels were measured by using real-time RT-PCR and flow cytometry analysis, respectively. The NLRP3-mediated secretion of IL-1β, IL-18 and IL-33 was detec-ted by ELISA combined with the NLRP3 inhibitory test. Results Compared with the normal cells, the ex-pression of NLRP3 at mRNA level in L. interrogans-infected THP-1 cells was respectively increased by 4. 05, 0. 34, 0. 33, 0. 06 and 1. 66 times at the time points of 1 h, 2 h, 4 h, 12 h and 24 h after infection ( P<0. 05), while that in L. interrogans-infected J774A. 1 cells was respectively increased by 12. 98, 16. 19, 10. 68, 5. 8 and 0. 57 times (P<0. 05). The expression rates of NLRP3 protein in THP-1 and J774A. 1 cells respectively increased from 9. 26% to 94. 01%, 89. 24%, 31. 80%, 19. 74%, 11. 28% and from 18. 71%to 58. 78%, 43. 64%, 36. 42%, 76. 46%, 85. 21% at the time points of 1 h, 2 h, 4 h, 12 h and 24 h af-ter L. interrogans infection (P<0. 05). The level of IL-1β in L. interrogans-infected THP-1 cells was 73. 07 pg/ml, 939. 24 pg/ml, 939. 24 pg/ml, 843. 22 pg/ml and 851. 06 pg/ml at the time points of 1 h, 2 h, 4 h, 12 h and 24 h, respectively (P<0. 05), while the level of IL-1β in L. interrogans-infected J774A. 1 cells began to rise at the time point of 12 h from 191. 17 pg/ml to 254. 4 pg/mL at the time point of 24 h (P<0. 05). The level of IL-18 in L. interrogans-infected THP-1 cells was 913. 89 pg/ml, 808. 19 pg/ml, 483. 54 pg/ml, 204. 19 pg/ml and 189. 09 pg/ml at the time points of 1 h, 2 h, 4 h, 12 h and 24 h, re-spectively (P<0. 05), while the level of IL-18 in L. interrogans-infected J774A. 1 cells increased at the time point of 24 h, which was 113. 37 pg/ml (P<0. 05). A slight increase in the level of IL-33 was detected in L. interrogans-infected J774A. 1 cells at the time points of 12 h and 24 h to 201. 14 pg/ml and 155. 68 pg/ml, respectively (P<0. 05), but no significant change was detected in L. interrogans-infected THP-1 cells (P>0. 05). Results of the inhibitory test showed that the up-regulation of IL-1β , IL-18 and IL-33 in THP-1 and J774A. 1 cells were effectively inhibited by the specific inhibitor of NLRP3. Conclusion NL-RP3 inflammasome was activated and involved in the production of specific inflammatory cytokines IL-1βand IL-18 in both THP-1 and J774A. 1 cells after L. interrogans infection, but the inflammatory cytokines induced by L. interrogans infection varied in different cells. L. interrogans induced earlier and higher level of IL-1βand IL-18 production in human macrophages than in murine macrophages.