ABSTRACT
Objective:To investigate the epidemiology, evolution and transmission characteristics of HIV-1 CRF07_BC in Nanjing between 2015 and 2019 to provide scientific basis for precise prevention and control of HIV-1 transmission.Methods:Pol gene sequences of 319 patients with HIV-1 CRF07_BC infection in Nanjing were amplified and sequenced and a maximum likelihood phylogenetic tree was then constructed. Markov Chain Monte Carlo sampling method was used to generate Maximum Clade Credibility Tree. Bayesian Skyline Plot was used to reconstruct the changing trend of the effective population size. Pairwise gene distance method was used to construct molecular network to investigate the transmission features. Results:Among the 319 patients, 303 (95.0%) were male; 264 (82.8%) had multiple sexual partners; only 14 (4.4%) had been using condoms. Most of the infections were occurred in men who have sex with men (MSM), accounting for 77.4%. The maximum likelihood phylogenetic analysis of HIV-1 CRF07_BC revealed two clusters: Cluster1 and Cluster2. Cluster1 mainly contained the strains isolated from MSM and Cluster2 mainly consisted of the strains isolated from heterosexual patients. The most recent common ancestor was 2002.47(1999.91, 2005.43) year for Cluster1 and 1996.38(1992.55, 1999.76) year for Cluster2. The evolutionary rates (95% highest posterior density, 95%HPD) of Cluster1 and Cluster2 were 1.73×10 -3 (1.36×10 -3-2.16×10 -3) substitutions·site -1·year -1 and 2.09×10 -3 (1.50×10 -3 -2.79×10 -3 ) substitutions·site -1·year -1, respectively. The effective population sizes of Cluster1 and Cluster2 tended to be stable after 2002 and 2003, respectively. In addition, Cluster1 and Cluster2 formed eleven and eight unique branches, respectively, suggesting the possibility of divergent epidemics of this genotype. A total of 35 propagation clusters were formed in the molecular propagation network, including 92 Nanjing sequences with an average degree of 4.3. Males, MSM and people with multiple sexual partners were more likely to be connected to the network. Students and young patients were more likely to be connected to the network. Conclusions:HIV-1 CRF07_BC infection was characterized by low age, multiple sexual partners, unprotected behaviors and transmission among MSM in Nanjing from 2015 to 2019. It was recommended to pay more attention to students and young people, to formulate more effective prevention and control measures for high-risk sexual behaviors, and to carry out continuous molecular monitoring of CRF07_BC strain, so as to provide scientific basis for the prevention and control of HIV CRF07_BC.
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Objective:To investigate HIV-1 genotypes and drug resistance among newly diagnosed young students in Nanjing in order to provide reference for the prevention and control of AIDS in this group.Methods:This study enrolled 200 newly diagnosed young students with HIV-1 infection in Nanjing from September 2015 to July 2019. Demographic information and blood samples were collected. Through RNA extraction and PCR amplification, 191 pol fragments were successfully obtained and subjected to genotyping and drug resistance analysis. Results:CRF01_AE (41.4%) and CRF07_BC (30.9%) were the predominant genotypes, followed by unique recombinant forms (URFs) (15.7%), CRF55_01B (5.2%), CRF68_01B (3.1%), CRF67_01B (2.6%), and subtype B (1.0 %). The incidence of drug-resistant mutations was 16.8%, and the rate of transmitted drug resistance (TDR) was 4.2%. The rates of TDR in CRF01_AE, CRF07_BC, CRF55_01B, URFs and other genotypes were 2.5%, 1.7%, 10.0%, 10.0% and 7.7%, respectively ( P>0.05). Conclusions:The rapid emergence of recombinant HIV-1 strains in the young students should be taken seriously. The prevalence of TDR was close to the alert level, thus needing to be monitored continuously.
ABSTRACT
Objective To explore the differences in the hippocampal delineation among different radiologists and to evaluate the impact of the delineating guideline training upon improving the accuracy of target area.Methods In this prospective study,20 patients scheduled to receive whole brain radiation therapy were selected.Before and after the delineating guideline training,three physicians from Department of Radiation Oncology delineated the hippocampal targets three times for each patient.One physician from Department of Imaging Diagnosis delivered the delineating guideline training and delineated the hippocampus of 20 patients as the standard target area.The delineating targets before and after the training were statistically compared among different physicians.Results The conformity indexes with the standard target of three physicians before and after the training were 0.66±0.04 and 0.77±0.02,0.62±0.04 and 0.76± 0.02,0.49±0.05 and 0.74±0.04,respectively.The conformity indexes were all statistically increased after the training (all P＜ 0.05).The inter-observer variability significantly differed among different physicians before and after training (all P＜0.05).The coefficient of variance of hippocampal volume before and after training were 0.16±0.06 and 0.08±0.04 with statistical significance (all P＜0.05).Compared with all targets before training,the consistency of each physician was significantly improved after training (all P＜0.05).Conclusion Hippocampal delineation guideline training can improve the accuracy of delineation.