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Objective To understand the major genotype-resistant mutation sites and change trends of HIV/AIDS patients with failure of antiviral therapy (ART) in Lincang City, Yunnan Province. Methods The In-House method was used to amplify the Pol gene region in the plasma samples of HIV/AIDS patients with failure of ART in Lincang City from 2011 to 2018. The target sequence was spliced and submitted to the HIV resistance database to identify and analyze the HIV-1 subtypes and resistant mutation sites. Results The 950 strains of HIV/AIDS patients with antiviral failure were mainly CRF08_BC, accounting for 75.5% (717/950), and the total gene mutation rate was 67.1% (637/950), which was dominated by non-nucleoside reverse transcriptase inhibitors (NNRTIs), accounting for 62.4% (593/950); followed by nucleoside reverse transcriptase inhibitors (NRTIs), accounting for 34.7% (330/950); protease inhibitors (PIs) was 7.5% (71/950). A total of 15 NRTIs of resistance-related mutation sites were detected, mainly M184V (29.3%) which was detected mostly in AZT/D4T+3TC+NVP programs; including 17 kinds of NNRTIs, mainly was K103N/S (25.1%)，the most detected in AZT/TDF+3TC+EFV programs. There were 22 kinds of PIs，mainly secondary sites were L10F/V/I (2.2%) and L33F (2.1%). The top three NRTIs mutation sites in the area were changed from T69D/N/G，M184I/V and D67N/G/S to M184I/V, K70R/Q/E/T and T215Y/F/V/I/N/A/D. NNRTIs mutation sites were changed from V179D/T/E/F, E138A/K/G/R and Y181C/F/G/V to K103N/S, E138A/K/G/R and V179D/T/E/F. The mutation sites of the first three PIs did not change much. Conclusions The second-line regimen based on PIs is a better choice in free antiviral treatments. Mastering the drug resistance of different gene mutations is beneficial to the compatibility of first-line drugs, thus delaying the use of second-line drugs.
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Objective To analyze the molecular epidemiological characteristics of 38 HIV-1 positive seroconcordant couples in Yunnan Province. Methods The samples of HIV-1 antibody screened initially and positive confirmed in the Laboratory of Yunnan Provincial Infectious Diseases Specialist Hospital from 2014 to 2016 and laboratory data were collected. 41 samples from HIV-1 positive seroconcordant couples were selected and sequenced by RT-nested-PCR amplification. After the sequences were aligned and spliced, the qualified pol gene region sequence was used to construct phylogenetic tree and analyze subtypes, and the gene distance differences between each positive couple were calculated. Results A total of 76 pol gene regions from 38 HIV-1 positive seroconcordant couples were obtained. The major gene subtypes included CRF08_BC (45,59.2%), CRF07_BC (18,23.7%) and CRF01_AE (7,9.2%), there were also C (4, 5.3%) and B (2, 2.6%). Phylogenetic tree analysis and gene distance calculation clearly showed that HIV transmission between relationship partners occurred in 9 HIV-1 positive seroconcordant couples. Conclusions As the proportion of sexual transmission of HIV has risen year by year, the transmission between husband and wife should be the focus of our attention. Late diagnosis of HIV infection is the main factor that causes the transmission between husband and wife. For special populations, monitoring and testing should be strengthened as soon as possible, so as to reduce the occurrence of transmission between AIDS couples.
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Since plague is an important natural focus zoonosis, the typing of natural plague foci becomes one of the elements in understanding the nature and developing related prevention program of the disease. Natural foci of plague are composed by four fundamental parts which include Eco-geographical landscape (natural plague foci), hosts, vectors and pathogens (Yersinia pestis) that comprehensively interact through the large temporal scale of evolution. Human activities have had great impact on the foci of natural plague. Based on the published serial research papers, we tried to integrate the knowledge of each factor in natural plague foci and focusing on theoretical aspects, so as to strengthen the prevention and surveillance programs of plague to be extrapolated to other zoonosis.
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Animals , Biological Evolution , China , Epidemiology , Disease Reservoirs , Geography , Insect Vectors , Plague , Epidemiology , Yersinia pestis , GeneticsABSTRACT
Objective To explore the predictors on the abundance of Rattus (R.) tanezumi in households of commensal rodent plague foci.Methods Thirty natural villages that experienced previous plague cases in Lianghe county,Yunnan province,were selected followed by random selection of 20 households in each village through computer technique.Live traps were set in households to capture small mammals which were then identified to species in the field according to their morphological features.Data on potential factors for abundance of R.tanezumi were collected through questionnaires and field observation and were coded and computerized using EpiData software and further analyzed by hurdle regression model under R software.Results A total of 166 rodents (133 R.tanezumi and 33 Suucus murinus) were captured.Results from final multilevel hurdle regression model showed that the likelihood of R.tanezumi captures increased by 1.67-to 2.76-fold in households belonged to Dai ethnic families that stored foodstuff in metal pails,often raising dogs,and having adjacent houses.The number of R.tanezumi captures increased by 2.18-fold in the villages where over 80％ of the households would raise chickens.In the villages with communal latrine,the likelihood and the number of R.tanezumi capture increased 1.93-fold and 2.38-fold,respectively.While the likelihood of R.tanezumi captures would reduce by 45％-61％ in those households where there were cats and cattle being raised and maize grown in the village.The number of R.tanezumi captures would reduce by 63％ in the households where there were outside toilets.Conclusion The abundance of R.tanczumi seemed to be closely related to the ecological environment factors.Programs on plague control and prevention should relate to ecological factors that influencing the abundance of R.tanezumi.
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Objective To express the plasminogen activator(Pla) of Yersinia pestis and one of its gene fragments,and to detect their immunological reactivity.Methods The pla gene and its specific gene fragment pla-c were amplified by PCR using the EV76 strain as a template.PCR products were then ligated with the plasmid pET32a (+).The recombinant plasmids pET32a (+)-pla and pET32a (+)-pla-c were subsequently trausformed into E.coli BL21 (DE3).The expressed products were purified by HIS affinity chromatography,and their immunological reactivity was detected by Western blotting.Results The recombinant Pla(52.8 × 103) was expressed as inclusion bodies,and the recombinant Pla-c protein (24.0 × 103) was expressed in the soluble form.These two recombinant proteins reacted with anti-Yersinia pestis EV76 rabbit sera.Conclusions The recombinant Pla and its specific fragments have displayed immunological reactivity,and can be served as an alternative diagnosis method for Yersinia pestis.
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Objective To group and characterize natural plague foci in China.Methods A novel two-class typing method as well as a three-indication nomenclature method were established to group and characterize the natural plague foci,on the basis of eco-geographical landscapes of plague foci,genetics of Yersinia pestis,zoology of rodent reservoirs and the entomology of flea vectors.Results A total of 12 distinct natural plague foci (including 19 subtypes) as well as their biological features were characterized.Conclusion Natural plague foci in China were grouped and characterized in this study.
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<p><b>OBJECTIVE</b>To investigate genomic variations of two Chinese Yersinia pestis isolates that were isolated from different plague foci obtained from vaccine strain EV76 from the Yunnan province of China.</p><p><b>METHODS</b>A microarray containing 12 000 probes covering the entire genome of seven Yersinia pestis and two Yersinia pseudotuberculosis strains, was used. PCR assays were performed to confirm microarray results.</p><p><b>RESULTS</b>The gene variations detected included the absence of five genes related to the synthesis of betaine in both EV76 and another sequenced attenuated strain, KIM D27. Several genes related to phage-related membrane proteins were found to be absent in the Antiqua biovar Yunnan strain, 485, which was isolated from a rodent plague foci.</p><p><b>CONCLUSION</b>These findings provide initial insight into the distinct strains isolated from natural foci, within their genomic context, including Yunnan Y. pestis strains. This information will be used therefore to establish subsequent comparisons of these sequences with published complete genomes of other strains.</p>
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China , Comparative Genomic Hybridization , Methods , Genome, Bacterial , Genetics , Polymerase Chain Reaction , Yersinia pestis , GeneticsABSTRACT
Objective To investigate the role of plasmid pYC on proteome of Yersinia pestis. Methods Two dimensional electrophoresis was performed to strains of Yersinia pestis with and without the pYC plasmid, and differential proteins were identified by mass spectrometry. Results More than 500 protein spots of Yersinia pestis with and without plasmid pYC were recognized,and their protein profiles were generally similar. The chaperone GroEL was highly expressed in strains with plasmid pYC, whereas the protein GroEL was not encoded by plasmid pYC. ConclusionsPlasmid pYC has an impact on proteome of Yersiniapestis. The proteins of pYC-p10 and pYC-p11 encoded by plasmid pYC may regulate the expression of GroEL.
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Objective To explore the relationship between wild rodent plague and human in wild rodent plague foci of the northwestern area in Yunnan to probe the possible transmission mechanism of wild rodent plague to human. Methods Data of component ratio of rodents and fleas was collected in different areas from 1985 - 1995. Activities and habits of residents regarding the way they keep cats and dogs and parasitic fleas and free fleas indoor were investigated, the dog serum was collected for detecting F1 antibody. Results Eothenomys miletus were main rodents in farmland and shrub, accounting for 48.00% (4753/9902) and 54.50% (4282/7857), Apodemus chevrieri were main rodents in garden, being 50.47% (1332/2639). The component ratio of Neopsylla specialis specialis was 13.31%(229/1720), 12.31%(1678/13 739) and 10.87%(957/8802) respectively in garden, farmland and shrub, higher than in indoor. The component ratio of Frantcpsylla spodix was 39.88% (686/1720), the highest in garden. Thirty-two per cent (32/100) of residents kept cats,in which 63% (20/32) with cat fleas, 68% (68/100) of villages kept dogs, in which 76%(52/68) with fleas. Eighteen parasitic fleas were caught from 43 dogs with a flea index of 0.119 and a rate for fleas of 11.63%, 7 pulex were collected from 17 indoor. Forty-three blood serum samples were obtained from dogs, among which 3 were positive blood serum. Conclusions Residents touch affected animals or media in different situations. The possibility of transmission for wild rodent plague to human exists in loci in a chain of wild rodent plague → fleas or predation → homebred animal plague (cats or dogs) →touching or respiratory → human.
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Objective To explore the mutation and evolution of Yersiniapestis(Y. pestis) from the point of codon and 16S-ribosome. Methods Codon preference and 16S-ribosome of Y. pestis were analyzed by bioinformatics. Results Similar codon preference was found among 4 PCD1 Y. pestis, of the 3 old Y. pestis the codon preference between PMT1 and PCD1 was similar. There were some differences between PCD1, PCP1 and Yunnan 6 kb plasmid. Through the analysis of 16S-ribosome, the sequences were found similar in 11 strains of Y. pestis,Yersinia pseudotuberculosis was very close to Y. pestis, with only one nucleotide difference, mutated G-T, and corresponding amino acid methionine (M)-isoleucine (I). There were some differences in sequences of 16S-ribosome in Y. pestis, Escherichia coli and Pulex irritans. Conclusions The time for Y. pestis to obtain PCP1 is later than PMT1 does, in other words, the affinity of Y. pestis with PMT1 was closer than PCP1 with 6 kb plasmid;alteration of 16S-ribosomal nucleotide sites may cause changes in function and structure of 16S rRNA. The lower similarity between 16S-ribosomal sequences of Y. pestis and Pulex irritans indicates the time for co-evolution is very short,and the late emergence of Y. pestis.
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Objective To evaluate the risk of plague occurrence via surveying and analyzing indoor rat density and flea index in natural villages having previous plague experience. Methods During August to September 2007, 30 natural villages experiencing previous plague were selected based on the surveillance data, and then all households were coded with numbers and 20 households in each village were randomly selected via computer. Cages and sticky papers were set in 600 selected households to capture rats and fleas. Rat density, flea prevalence, flea index and median were estimated. Results One hundred thirty-three Rattus flavipectus and 33 Suncus murinus were caught and averaged rat density was 2.8 rats per one hundred cage. nights (166/6000), the median was 5 rats each village. One hundred and one mice infected fleas, flea prevalence on rats was 60.8% (101/166), 296 Xenopsylla cheopis and 48 Leptopsylla segnis were collected. Rat flea index was 2.1 fleas per rat (344/166). A total of 315 dissociated flea was caught, average dissociated flea index was 0.026 fleas per sticky paper (315/11888). The median was 5.5 dissociated fleas per village. Of dissociated fleas, Ctenocephalides felis felis (205) and Xenopsylla cheopis (103) accounted for 97.8% (308/315). The proportion for species of the rat flea and the dissociated flea was different(Fisher test: P < 0.01). The rat flea was significantly associated with the rat density(r = 0.68, P < 0.01), but the dissociated flea was significantly associated with neither the rat density(r = -yield than fried wheat batter(χ2 = 5.59, P < 0.05). Conclusions In these villages having previous plague experience of Lianghe County, Rattusflavipectus was dominant species of indoor rats, Xenopsylla cheopis and Ctenocephalides felis felis were dominant species of rat flea and dissociated flea, respectively. Mengsong, Bangdu, and Tangjiatun village had potential risk of plague emergence.
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Objective To analyze nucleic acid sequence homology of the 6 kb(pYC) plasmid of Yersina. pestis (Y. pestis) isolated from Yurman by searching GenBank. Method The search of sequence similarity was accomplished with BLAST. Results The pYC plasmid sequence had high homology with some genes in nueleotide sequence, such as: 97.1% homology with Shigella sonnei pKYM, 92.1% homology with Haemophilus influenzae(H. influenzae) gene, Salmonella typhi (S. typhi) gene LT2 and plMVSI with 88.2% and 87.2% of homology respectively, Escherichia coli(E, coli) O157:H7 and K-12, ECOR31 with 81.4%, 81.4% and 84.7% of homology respectively. This plasmid ORFs could code for some proteins which were similar with others in GenBank, such as: ORFi and H. paragallinarum replication protein B(47.2%), ORF4 and E. coli hypothetical protein(52.7%), ORF5 and Y. pseudotuberculosis Tile (48.3%), ORF6 and E. coil Pilx5/VirB5-1ike protein (42.3%), Y. enterocolitica TriD protein(38.5%), ORFIO and S. typhimurium LT2, E. coli O157:H7 hypothetical protein(83.1% and 81.9%, respectively), ORF11 and E. coli, damage-inducible protein J(81.4%). Conclusions The pYC plasmid sequence has high homology with a few bacterial genes of Enterobacteriaceac. This plasmid may code for some proteins that are similar with hypothetical protein, damnge-indncible protein, TriD and TilE protein, Pilx5/VirB5-hke protein of Escherichia or Yersinia.
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Objective To analyze the epidemiologic characters of human plague from Rattus flavipectus plague natural foci in Yunnan Province from 1986 to 2006 and to provide references for prevention and control strategy.Methods Data were collected and analyzed on epidemic situation of human plague in the past twenty-one years.Results From 1986 to 2006,the total human plague cases from Rattus flavipectus plague natural foci in Yunnan were 507,accounted for 59.5%(507/866)of the total cases in the whole country.There were three peaks of human plague outbreak in 1990,1996 and 2000.The number of annual cases were 73,88 and 122,accounting for 97.3%(73/75),89.8%(88/98),48.0%(122/254)of the total cases in the whole country respectively.The epidemic areas were mainly located in the west,southwest and southeast pans of Yunnan,but the number of cases changed with year in different prefectures(or cities).Seasonal pattern analyses revealed that the epidemic could occur in whole year,with a peak period through July to November,especially September.There were different prevalence of plague cases in age and professions,which related to the chance of contact with infected animals and infectious fleas.All human plague cases were primary bubonic plague.Conclusions The results suggested that there were clear epidemic characteristics for human plague for Rattus flavipectus plague natural foci in Yunnan.In order to control human plague effectively,it was necessary to reinforce surveillance and warning system to diminish the outbreak of human plague.
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Objective To study the epidemiological significance of community-structural difference regarding both small mammal and flea communities on Rattus ftavipectus in Dehong and Baoshan areas,Yunnan province,during 1982 to 1996.Methods Methodologies as cluster analysis,communities dominated constitution and species diversity were used for data analysis.Results 75 490 small mammals of 27 species could be divided into three types:Ⅰ.Ruili habitat-communities dominated bv R.flavipectus (54.41%)and Suncus murinus(33.37%): Ⅱ.Longchuan and Yingiiang habitat-communities dominated by R.flavipectus(62.99%),S.murinus(23.25%)and Mus musculus(10.06%);Ⅲ.Baoshan habitat-community dominated by R.flavipectus(48.07%),S.murinus(19.56%)and Crocidura attenuats(14.37%).The captured 61 122 fleas of 11 species on R.flavipectus could be divided into three types: i.Ruili habitat-communities dominated by Xenopsylla cheopis(83.51%)and Lentistivslius ferinus(13.86%);ii.Longchuan and Yingjiang habitats X.cheopis(74.42%)and L.segnis(22.94%); iii.Baoshan habitat-communities dominated by L.segnis(70.62%)and X.cheopis(22.70%).There had been 1471 strains of Y.pestis isolated from the hosts of 7 species and vectors of 5 species in Dehong areas for the ten year period.36 strains of Y.pestis were isolated from host of one species and vectors of 2 species in Baoshan area for ten years.The constitution ratio of R.flavipectus and X.cheopis was higher in Dehong area with average as 58.70%and 78.97%respectively.However.the diversities of species among host and vector communities were low,with average as 1.010 and 0.625.On the contrary,the constitution ratios of R.flavipectus and X.cheopis were lower in Baoshan area.with an average as 48.07%and 22.70%respectively but the diversities of species among host and vector community were higher with the averages as 1.471 and 0.829 respectively.The main dominative flea species from 'group ii'to 'group iii'in the flea community had changed from X.cheopis to L.segnis.Conclusion The species diversity index of host and vector community was higher in Baoshan area,while the constitution ratio of main host and vector community was lower.This findings seemed to be the important factor of the decrease of plague prevalence in Baoshan area.
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<p><b>OBJECTIVE</b>To understand the epidemiologic and clinical characteristics of the "Yunnan unknown-cause sudden cardiac death (YUSCD)".</p><p><b>METHODS</b>Cases of YUSCD occurred in 2002-2004 were investigated with cross-sectional study. Clinical manifestation was observed and analyzed.</p><p><b>RESULTS</b>The YUSCD areas were mountainous and most of the YUSCD cases appeared between June and August. Most of the YUSCD cases were young farmers and showed family/village clustering nature. Most of the patients died quickly with only few recovered. The overall incidence of YUSCD was 1.83% with mortality as 1.51%. The fatality rate of YUSCD appeared to be 78.1%.</p><p><b>CONCLUSION</b>The YUSCD cases had a clustering feature along with time and area. The clinical manifestation of YUSCD could not be specifically identified, making the clinical diagnosis and treatment difficult when practicing in the fields that called for further studies on epidemiology, clinical work and etiology.</p>
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Humans , China , Epidemiology , Cross-Sectional Studies , Death, Sudden, Cardiac , Epidemiology , SeasonsABSTRACT
<p><b>OBJECTIVE</b>The strains of Yersinia pestis isolated in different period and different natural foci in China were analyzed.</p><p><b>METHODS</b>Traditional and molecular biological methods were used. Rhamnose fermentation, rRNA gene copy number, nitrite reduction, and the glycerol fermentation were important characters for typing, and pulse field gel electrophoresis (PFGE) and random amplified polymorphic DNA (RAPD) profile could reflect the genetic distance between the strains.</p><p><b>RESULTS</b>The strains could be divided into 15 genetic types by those 6 characters with each of them covered an isolated geographical territories.</p><p><b>CONCLUSION</b>The characters of strains were described; the genetic relationship of different types, their evolution, and the forming and shift of plague natural foci were analyzed.</p>