[Study on the association between genetic variation of gag gene and HLA restricted CTL response in HIV-1 B' infected Chinese people].

OBJECTIVE: To identify the genetic variation of Gag gene in HIV-1 B' subtype infected Chinese people and to evaluate the association between the positive selection sites and HLA restricted CTL response. METHODS: We downloaded all HIV-1 B' subtype gag gene sampled from China from the LANL HIV database. The sequences were grouped by years of collection and the mean intra-subtype diversity and divergence were examined by MEGA 5.0 software. The sites under positive selection were estimated by using Hyphy software. Then analyzed the association between positively selected sites and HLA restricted CTL epitopes. RESULTS: A set of 122 B' subtype HIV-1 gag sequences were collected from Henan, Hubei, Liaoning and Yunnan provinces, grouped by sampling year as < 2001, 2001 - 2003, 2004 - 2006 and 2007 - 2010. The mean intra-subtype diversity and divergence increased over time (r(1) = 0.497, P1 < 0.001; r(2) = 0.593, P2 < 0.001). This analysis revealed 34 positively selected sites and 97.1% of these sites were located within 47 known CTL epitopes. The most frequent HLA was HLA-A*02 (21.6%) followed by A*11(9.8%), B*35(9.8%) and B*57(5.9%). The percentages of HLA-A/B/C limited CTL epitopes were 43.1%, 49.0% and 7.9%, respectively. CONCLUSION: The mean intra-subtype diversity and divergence of B' subtype gag sequences increased over time. B' subtype HIV-1 virus has accumulated adaptations to HLA restricted CTL responses in HIV-1 infected Chinese.

CT virtual endoscopy of the ampulla of Vater: preliminary report.

AIM: To explore multi-slice spiral CT (MSCT) virtual endoscopy (CTVE) in the detection of Vater's ampulla lesions. METHODS: In addition to 30 healthy volunteers, 18 cases of common bile duct stones, and 7 cases of ampullary carcinoma were scanned with MSCT including virtual endoscopy (VE) reconstruction. Patterns of the duodenal papilla were then observed, and its size was measured. RESULTS: Reconstructed images of CTVE in the volunteers showed that the normal type of the duodenal papilla was nodular in 16 cases, V-shaped in 8 cases, and Y-shaped in 6 cases. Its mean diameter was 0.84 ± 0.17 cm in the healthy volunteers; in patients with common bile duct stones of nodular type, mean diameter was 1.72 ± 0.32 cm. In ampullary cancer patients with an irregular protruded type, its diameter was 2.30 ± 0.85 cm, Overall the mean differences between the groups were statistically significant (P < 0.001). CONCLUSION: CTVE is a convenience, no-wound, and precise clinical examination mode utilizing which the shape of duodenal papilla can be observed, and size of the latter can be measured.

[Coreceptor usage of human immunodeficiency virus-1 in primary infection through sexual contact transmission].

OBJECTIVE: To evaluate the coreceptor usage characters and evolution of human immunodeficiency virus-1 (HIV-1) primary infection. METHODS: A total of 12 HIV-1 primary infection cases were recruited from a high-risk population for this prospective cohort trial. The blood samples were collected at the earliest time after infection and after a viral setpoint respectively. RNA was extracted from plasma. The env genes were amplified through reverse transcription-PCR (RT-PCR) and nested PCR. And the env fragments were ligated to T vector and then sequenced. The pattern of coreceptor usage was predicted with five different online tools. RESULTS: Among them, 11 were predicted as CCR5 virus transmission and 1 as CXCR4 virus transmission. The viruses in 1 case were detected as a switch of coreceptor usage from CCR5 to CXCR4. The consistency of five different prediction rules was 88.3%. CONCLUSION: Although the CCR5 usage virus is predominant in primary infection through sexual transmission, CXCR4 usage virus can also be detected. A switch of coreceptor usage may happen within the first year post-infection. Adopting multiple rules may improve the efficiency and validity for the prediction of coreceptor usage based on genotypes.

Prevention and control of HIV/AIDS in China: lessons from the past three decades.

ABSTRACT: In the past 37 years, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) has undergone various major transmission routes in China, with the world most complex co-circulating HIV-1 subtypes, even the prevalence is still low. In response to the first epidemic outbreak of HIV in injecting drug users and the second one by illegal commercial blood collection, China issued the Anti-Drug Law and launched the Blood Donation Act and nationwide nucleic acid testing, which has avoided 98,232 to 211,200 estimated infections and almost ended the blood product-related infection. China has been providing free antiretroviral therapy (ART) since 2003, which covered >80% of the identified patients and achieved a viral suppression rate of 91%. To bend the curve of increasing the disease burden of HIV and finally end the epidemic, China should consider constraining HIV spread through sexual transmission, narrowing the gaps in identifying HIV cases, and the long-term effectiveness and safety of ART in the future.

[Study on the rates of infection and spontaneous clearance on HCV among HIV-infected men who have sex with men in China].

OBJECTIVE: The aim of this study was to understand the rates of infection and spontaneous clearance on hepatitis C virus (HCV) among HIV-infected men who have sex with men (MSM) in China. METHODS: HIV-infected MSM from Shenyang, Beijing, Changsha and Kunming were selected to take the HCV antibody and HVC-RNA tests, and then classified into 'under recovery (RNA-/Ab+) ' or being chronic (RNA+/Ab+). Information on demography, CD4(+) T cell, HIV viral load and liver biochemical indicators were also collected. RESULTS: In 513 HIV-infected MSM, the positive rate of HCV antibody was 1.94% (10/513) and the positive rate of HVC-RNA was 0.77% (4/513). Five patients showed clearance of HVC-RNA, spontaneously. These 5 patients had low levels of both alanine transaminase (ALT) and aspartate aminotransferase (AST), and with high level of CD4(+) T cells, when compared to those who were not able to clear the HVC-RNA. CONCLUSION: Currently, the HCV infection rate was still at quite low level among the HIV-infected MSM in China. Dynamic of HIV/HCV co-infection should be monitored so as to develop suitable strategy on prevention and treatment among this population, in China.