Molecular characteristics of Neisseria gonorrhoeae isolates with decreased susceptibilities to ceftriaxone in Shenzhen from 2009 to 2011 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the genotype and characteristics of Neisseria gonorrhoeae (N.gonorrhoeae) isolates with reduced susceptibility to ceftriaxone in Shenzhen from 2009 to 2011.</p><p><b>METHODS</b>A total of 296 N.gonorrhoeae isolates were collected in Shenzhen from 2009 to 2011.ceftriaxone strains (minimum inhibitory concentration between 0.06 and 0.50 µg/ml) were determined by agar dilution method.Logistic regression was used to analyze the associated factors of ceftriaxone N.gonorrhoeae infection.Neighbor-joining (NJ) phylogenetic tree analysis and N.gonorrhoeae multi antigen sequence typing (NG-MAST) were performed on all ceftriaxone isolates and susceptible control isolates randomly selected in accordance with the principle of 1: 1 sampling.</p><p><b>RESULTS</b>No isolates displayed resistance to ceftriaxone, whereas 53(17.9%) showed reduced susceptibility to ceftriaxone among 296 isolates.Only antibiotic use in recent two months was associated with ceftriaxone isolates infection (OR = 3.080, 95%CI: 1.376-6.894) . Among the ceftriaxone isolates, 48 different ST were identified including 5 STs (ST1768, ST3927, ST641, ST7076 and ST7078) containing 2 isolates and 43 single STs. There were 26 STs previously reported from HongKong in China.Low sensitive strains clustering was not observed by NJ phylogenetic tree.</p><p><b>CONCLUSION</b>The proportion of ceftriaxone strains among the 296 N.gonorrhoeae isolates collected from 2009 to 2011 in Shenzhen is high. The STs of ceftriaxone strains may have unique epidemic features in Shenzhen.</p>

Study on the molecular-epidemiological characteristics of HIV-1 in Shenzhen, 1992- 2008 / 中华流行病学杂志

Objective To investigate the epidemiological characteristics of HW-1 subtype in Shenzhen from 1992 to 2008.Methods 489 HIV-1 positive plasma samples were collected from 1992 to 2008 in Shenzhen.HIV-1 env genes were amplified by nested-PCR from RNA.Phylogenetic analysis was performed on data regarding the nucleotide sequence.Results A total of 464 sequences were amplified and genotyped.Data from this study revealed that CRF01_AE was a predominant HIV-1 subtype in Shenzhen (64.4％,299/464),followed by subtypes CRF_BC( 17.5％,81/464),B'( 14.7％,68/464) and B (2.4％,11/464).Subtype C (0.4％,2/464),A1 (0.2％,1/464),CRF02_AG(0.2％,1/464) and CRF06_cpx (0.2％,1/464) were also prevalent in Shenzhen.CRF01_AE and CRF_BC were predominant among heterosexuals,homosexuals and injection drug users,while B'was predominant among blood donors.Results from phylogenetic tree analysis showed that some of the HIV-1 clusters had been defined in CRF01_AE strains at different time or groups with different transmission routes.Cross-infections were also seen.Conclusion CRF01_AE was the predominant HIV-1 subtype in Shenzhen while CRF_BC,B,B',C,A1,CRF02_AG and a small amount of CRF06_cpx or recombinant subtypes were prevalent in this city.Different subtypes showed great variation in the process of epidemics.

Epidemic trend and evolution of HIV-1 CRF01_AE strains isolated from 1992 through 2008 in Shenzhen district / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the prevalent status of CRF01_AE strains of recombinant HIV-1 in Shenzhen and their source of infection in order to predict the epidemic trend and evolution.</p><p><b>METHODS</b>A total of 489 samples of HIV-1 positive plasma were collected from 1992 to 2008 in Shenzhen. HIV-1 Env genes were amplified by nested-PCR from RNA. Subtype analysis were performed on the nucleotide sequence data. CRF01_AE sequences were analyzed by phylogenetic methods and characterized by calculating the genetic distance.</p><p><b>RESULTS</b>A total of 300 CRF01_AE strain sequences were amplified, accounting for 64.5% of all genotyped samples of all the 465 samples. The CRF01_AE strains of recombinant in 1992 - 1999, 2000 - 2005 and 2006 - 2008 accounted for 56.8% (21/37), 68.4% (78/114) and 64.0% (201/314) of genotyped samples, respectively. And in these three periods of times, 52.4% (11/21), 43.6% (34/78) and 45.8% (92/201) were heterosexually acquired adults; 4.8% (1/21), 0.0% (0/78) and 22.4% (45/201) were homosexually acquired adults; 19.0% (4/21), 51.3% (40/78), 30.8% (62/210) were intravenous drug users, respectively.Phylogenetic tree analysis revealed that HIV samples from different period of time showed distinct aggregation in time and transmission as well as cross infection. The gene divergence rate of CRF01_AE strains in the three different periods of time were (8.783 ± 4.717)%, (11.054 ± 7.141)%, and (13.218 ± 4.080)%, respectively.</p><p><b>CONCLUSION</b>CRF01_AE is the major epidemic strains in Shenzhen, which is transmitted through heterosexual contact, MSM and intravenous drug users. The gene variation increased gradually as time goes by.</p>

Molecular epidemiological survey on HIV-1 among the injecting drug users population in Shenzhen / 中华流行病学杂志

Objective To study the prevalent status of human immunodeficiency virus-1 (HIV-1) subtypes in IDU (injecting drug users) population in Shenzhen and to study their source of infection in order to predict the epidemic trend and evolution. Methods 166 HIV-1 positive plasma from the IDUs was collected from 1996 to 2008. HIV-1 env genes were amplified by nested-PCR from RNA. The C2-V3 regions (450 bp) of HIV-1 env were sequenced for analyses. Phylogenetic analyses were performed on the nucleotide sequence data. Results Among 166 samples, there were 6 HIV-1 strains including CRF01_AE, CRF08_BC, CRF07_BC 3 circulating recombinant forms (CRFs) and B',C, A1 3 subtypes. Data from the genotype analyses showed that 65.06% (108/166) were CRF01_AE, 19.88% (33/166) were CRF07 BC_6.02% (10/166) were CRF08_BC, 7.23%(9/166) were subtype B', 0.60% (1/166) were subtype C and 1.20% (2/166) were subtype A1. Phylogenetic tree analysis showed that some of HIV-1 clusters defined in CRF01_AE, CRF07_BC and subtype B' in different time groups. Significant increase of gene distance in CRF01_AE and CRF07_BC strains in the three different periods. Conclusion CRF01_AE and CRF07_BC were the major epidemic CRF strains among the IDU population in Shenzhen while the subtype B', C, A1 and CRF08_BC were also circulating in IDU population in this region. The variation of all different subtypes was increasing through these years.

Analysis of the tandem-repeat polymorphisms in DC-SIGNR alleles among drug users population with or without HIV/HCV infection / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the distribution of DC-SIGN/DC-SIGNR alleles among drug user (DUs) populations with or without HIV/HCV infection in Shenzhen, and to evaluate the role of these alleles in the construction of genetic resistance to HIV or HCV and screen out the anti-HIV/HCV gene in Shenzhen.</p><p><b>METHODS</b>All 500 DU blood samples were collected from Shenzhen Detoxification Center, including 313 from injected drug users (IDUs). All samples were screened for HIV and HCV antibody by means of ELISA. The genomic DNA were extracted and amplified by PCR. The neck domain repeat regions of DC-SIGN/DC-SIGNR were sequenced directly from the PCR products to confirm the amplification for some samples and all positive PCR products were analyzed by agarose gel electrophoresis.</p><p><b>RESULTS</b>Of 500 samples, 97 were found HIV positive, all of which were IDUs and HCV positive. The total positive rate of HCV among all HIV negative DU was 57.57% (232/403), and it was 63.89% (138/216) among IDUs; in comparing to the 50.26% (94/187) of DUs with other manners there showed significant difference (chi(2) = 7.61, P = 0.0058). Among HIV + DUs, there was a higher proportion of patient with the DC-SIGNR 5/6 and 5/8 (Fisher's exact, P = 0.043 and P = 0.034) with statistical significance; there was no statistically significant difference between HCV + and HCV-DUs and no significant difference between IDUs and other DUs for the DC-SIGNR polymorphism.</p><p><b>CONCLUSION</b>The results might indicate that DC-SIGN/DC-SIGNR polymorphism might not influence the susceptibility to HCV. Genotype 5/6 might probably have a relation with HIV infection, but still need further investigation for the low frequency.</p>

Human immunodeficiency virus type 1 strains epidemic in Shenzhen / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the epidemic status of human immunodeficiency virus type 1 (HIV-1) subtypes in Shenzhen and to study their transmission source and routes.</p><p><b>METHODS</b>HIV-1 env and gag genes were amplified by nested PCR from uncultured peripheral blood mononuclear cells (PBMCs) obtained from 122 HIV-1 carriers confirmed in Shenzhen. The C2-V3 region (about 450 bp) of HIV-1 env and P17/ P24 region were sequenced.</p><p><b>RESULTS</b>Among 122 samples, 6 HIV-1 strains including 3 circulating recombinant forms (CRFs) of CRF01_AE, CRF08_BC, CRF07_BC and 3 subtypes of B', B, C were found in Shenzhen, and the percentages were 45.1% (55/122) for CRF01_AE, 31.1% (38/122) for CRF08_BC, 6.6% (8/122) for CRF07_BC, 14.8% (18/122) for B' subtype, 1.6% (2/122) for B subtype, and 0.8% (1/122) for C subtype. The intragroup genetic distances were (4.455 +/- 1.478)%, (2.997 +/- 1.345)%, (4.380 +/- 2.024)%, (5.186 +/- 2.487)%, and (4.869 +/- 2.638)%, respectively. In comparison with the sequence of respective international strains 01AE. TH. 90. CM240, 97CNGX-9F, CN. 97. C54A, B. US. 83. JRFL, and RLA2, the genetic distances were (5. 228 +/- 0.823)%, (3.634 +/- 1.073)%, (4.233 +/- 1.119)%, (4.950 +/- 2.564)%, and (5.795 +/- 2.198)%, respectively. The major subtypes found in injection drug users (IDUs) were CRF07_BC, CRF08_BC, and CRF01_AE strains. CRF01_AE and B' strains were epidemic mainly in sexual workers.</p><p><b>CONCLUSION</b>There are 3 HIV-1 subtypes (B', B, C) and 3 CRFs (CRF01_AE, CRF08_BC, CRF07_BC) epidemics in Shenzhen. The predominant subtypes varies among different transmission routes. While CRF01_AE is predominant among sexual workers, CRF08_BC and CRF01_AE are major subtypes among IDU population.</p>