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1.  Design, Synthesis and Biological Evaluation of 1-[(2-benzyloxyl/alkoxyl) methyl]-5-halo-6-aryluracils as Potent HIV-1 Non-Nucleoside Reverse Transcriptase Inhibitors with Improved Drug Resistance Profile 
Journal of Medicinal Chemistry  2012;55(5):2242-2250.
Since the emergence of drug-resistant mutants has limited the efficacy of non-nucleoside reverse transcriptase inhibitors (NNRTIs), it is essential to develop new antivirals with better drug-resistance and pharmacokinetic profiles. Here we designed and synthesized a series of 1-[(2-benzyloxyl/alkoxyl)methyl]-5-halo-6-aryluracils, the HEPT analogues, and evaluated their biological activity using Nevirapine and 18 (TNK-651) as reference compounds. Most of these compounds, especially 6b, 7b, 9b, 11b and 7c, exhibited highly potent anti-HIV-1 activity against both wild-type and NNRTI-resistant HIV-1 strains. The compound 7b, that had the highest selectivity index (SI = 38,215), is more potent than Nevirapine and 18. These results suggest that introduction of halogen at the C-5 position may contribute to the effectiveness of these compounds against RTI-resistant variants. In addition, m-substituents on the C-6 aromatic moiety could significantly enhance activity against NNRTI-resistant HIV-1 strains. These compounds can be further developed as next-generation NNRTIs with improved antiviral efficacy and drug-resistance profile.
doi:10.1021/jm201506e
PMCID: PMC3312045  PMID: 22283377
HIV-1; Non-nucleoside reverse transcriptase inhibitors (NNRTIs); Drug-resistance
2.  Short-term safety of buprenorphine/naloxone in HIV-seronegative opioid-dependent Chinese and Thai drug injectors enrolled in HIV Prevention Trials Network 058 
Background
Buprenorphine/naloxone (BUP/NX) is not licensed for use in China or Thailand and there was little clinical experience with this drug combination in these countries at the inception of HIV Prevention Trial Network (HPTN) 058, a randomized trial comparing risk reduction counseling combined with either short-term or long-term medication assisted treatment with BUP/NX to prevent HIV infection and death among opioid-dependent injectors.
Methods
We conducted a safety phase that included the first 50 subjects enrolled at each of the three initial study sites (N=150). Clinical and laboratory assessments were conducted at baseline and weekly for the first 4 weeks. Changes in laboratory parameters were estimated with random effects models.
Results
BUP/NX was well tolerated by study subjects and opioid withdrawal scores decreased substantially during the 3-day induction. Two participants experienced grade 3 clinical adverse events, which were categorized as probably not related to the study drug. Grade 2 or 3 increases in alanine aminotransferase (ALT) occurred in 25 (17%) subjects. The magnitude of ALT increase over 4-week follow-up was strongly associated with baseline ALT elevation.
Conclusions
In Chinese and Thai opioid-dependent injectors, we found BUP/NX to be effective in reducing opioid withdrawal symptoms and safe during short-term use. ALT increases were observed over 4-week-follow-up, which are consistent with reports from Western populations. Long-term safety and efficacy evaluations are indicated.
doi:10.1016/j.drugpo.2011.06.005
PMCID: PMC3236277  PMID: 21852093
buprenorphine/naloxone; injection drug use; opioid dependence; HIV prevention; risk reduction counseling; safety; hepatic toxicity
3.  Behavioral and Serologic Survey of Men Who Have Sex with Men in Beijing, China: Implication for HIV Intervention 
AIDS Patient Care and STDs  2012;26(3):148-155.
Abstract
We assessed HIV prevalence and associated behaviors and risk factors among men who have sex with men (MSM) in Beijing, China. Five hundred MSM were recruited for a biological and behavioral survey using respondent-driven sampling (RDS) in 2009. Serologic specimens were tested for markers of HIV and syphilis infection. A computer-assisted personal interview (CAPI) administered questionnaire gathered information including demographic characteristics, sexual behaviors, HIV testing, and social norms concerning condom use. The adjusted HIV prevalence was 8.0%, syphilis 22.0%. HIV testing and disclosure was low; only 39.3% had HIV tested in the past 12 months, 49.7% knew their own HIV status and 22.8% knew their last male partner's HIV status. HIV infection was associated with syphilis, ever having sex with a woman, not knowing the HIV status of the most recent male partner, and never buying condoms in the past 12 months. Stronger endorsement of positive social norms around condom use strongly and predicted lower prevalence of HIV infection. Compared to surveys of similar design in the recent past, HIV continues to spread rapidly among Beijing's MSM. Our results identify points of intervention that, if addressed in time, may still alter the course of the epidemic including the promotion of HIV testing and partner disclosure, syphilis control and particularly changing social norms around condom use.
doi:10.1089/apc.2011.0277
PMCID: PMC3326445  PMID: 22248333
4.  Compromised NK Cell-Mediated Antibody-Dependent Cellular Cytotoxicity in Chronic SIV/SHIV Infection 
PLoS ONE  2013;8(2):e56309.
Increasing evidence indicates that antibody-dependent cellular cytotoxicity (ADCC) contributes to the control of HIV/SIV infection. However, little is known about the ADCC function of natural killer (NK) cells in non-human primate model. Here we demonstrated that ADCC function of NK cells was significantly compromised in chronic SIV/SHIV infection, correlating closely with the expression of FcγRIIIa receptor (CD16) on NK cells. CD32, another class of IgG Fc receptors, was identified on NK cells with higher expression in the infected macaques and the blockade of CD32 impacted the ability of NK cells to respond to antibody-coated target cells. The inhibition of matrix metalloproteases (MMPs), a group of enzymes normally involved in tissue/receptor remodeling, could restore NK cell-mediated ADCC with increased CD16 expression on macaque NK cells. These data offer a clearer understanding of NK cell-mediated ADCC in rhesus macaques, which will allow us to evaluate the ADCC repertoire arising from preclinical vaccination studies in non-human primates and inform us in the future design of effective HIV vaccination strategies.
doi:10.1371/journal.pone.0056309
PMCID: PMC3570461  PMID: 23424655
5.  HIV Drug Resistance and Its Impact on Antiretroviral Therapy in Chinese HIV-Infected Patients 
PLoS ONE  2013;8(2):e54917.
Background
Highly active antiretroviral therapy (HAART) has significantly decreased mortality among Chinese HIV patients. However, emerging HIV drug resistance (HIVDR) poses a growing threat to the long-term success and durability of HAART.
Methods
Three cross-sectional surveys were conducted across the country from 2004 to 2006, respectively. Patients completed a questionnaire and provided blood for CD4 cell count, HIV viral load (VL), and HIV resistance genotyping. Factors associated with HIVDR were identified by logistic regression.
Results
3667 unique patients were included across the three surveys. Among 2826 treatment-experienced patients, median duration of treatment was 17.4 (IQR 8.6–28.4) months and HIVDR was identified in 543 (19.2%). Factors significantly associated with HIVDR included ART drug distribution location, CD4 cell count, initial HAART regimen, self-reported medication adherence, and province.
Conclusions
Virologic failure increased over time on therapy but a significant proportion of patients in failure had no resistance mutations identified, suggesting that treatment adherence is suboptimal and must be emphasized. Due to the significantly higher risk of HIVDR in certain provinces, additional steps to reduce HIVDR should be taken.
doi:10.1371/journal.pone.0054917
PMCID: PMC3566114  PMID: 23405098
6.  Neutralization sensitivity of HIV-1 subtype B’ clinical isolates from former plasma donors in China 
Virology Journal  2013;10:10.
Background
HIV-1 subtype B’ isolates have been predominantly circulating in China. Their intra- and inter-subtype neutralization sensitivity to autologous and heterologous plasmas has not been well studied.
Results
Twelve HIV-1 B’ clinical isolates obtained from patients were tested for their intra- and inter-subtype neutralization sensitivity to the neutralization antibodies in the plasmas from patients infected by HIV-1 B’ and CRF07_BC subtypes, respectively. We found that the plasmas from the HIV-1 B’-infected patients could potently neutralize heterologous viruses of subtype B’ with mean ID50 titer (1/x) of about 67, but they were not effective in neutralizing autologous viruses of subtype B’ with mean ID50 titer (1/x) of about 8. The plasmas from HIV-1 CRF07_BC-infected patients exhibited weak inter-subtype neutralization activity against subtype B’ viruses with ID50 titer (1/x) is about 22. The neutralization sensitivity of HIV-1 B’ isolates was inversely correlated with the neutralizing activity of plasmas from HIV-1 B’-infected patients (Spearman’s r = −0.657, P = 0.020), and with the number of potential N-glycosylation site (PNGS) in V1-V5 region (Spearman’s r = −0.493, P = 0.034), but positively correlated with the viral load (Spearman’s r = 0.629, P = 0.028). It had no correlation with the length of V1-V5 regions or the CD4+ T cell count. Virus AH259V has low intra-subtype neutralization sensitivity, it can be neutralized by 17b (IC50: 10μg/ml) and 447-52D (IC50: 1.6μg/ml), and the neutralizing antibodies (nAbs) in plasma AH259P are effective in neutralizing infection by the primary HIV-1 isolates with different subtypes with ID50 titers (1/x) in the range of 32–396.
Conclusions
These findings suggest that the HIV-1 subtype B’ viruses may mutate under the immune pressure, thus becoming resistant to the autologous nAbs, possibly by changing the number of PNGS in the V1-V5 region of the viral gp120. Some of primary HIV-1 isolates are able to induce both intra- and inter-subtype cross-neutralizing antibody responses.
doi:10.1186/1743-422X-10-10
PMCID: PMC3599083  PMID: 23289760
HIV-1 subtype B’; Clinical isolates; Neutralization sensitivity
7.  High Resolution Human Leukocyte Antigen Class I Allele Frequencies and HIV-1 Infection Associations in Chinese Han and Uyghur Cohorts 
PLoS ONE  2012;7(12):e50656.
Background
Host immunogenetic factors such as HLA class I polymorphism are important to HIV-1 infection risk and AIDS progression. Previous studies using high-resolution HLA class I profile data of Chinese populations appeared insufficient to provide information for HIV-1 vaccine development and clinical trial design. Here we reported HLA class I association with HIV-1 susceptibility in a Chinese Han and a Chinese Uyghur cohort.
Methodology/Principal Findings
Our cohort included 327 Han and 161 Uyghur ethnic individuals. Each cohort included HIV-1 seropositive and HIV-1 seronegative subjects. Four-digit HLA class I typing was performed by sequencing-based typing and high-resolution PCR-sequence specific primer. We compared the HLA class I allele and inferred haplotype frequencies between HIV-1 seropositive and seronegative groups. A neighbor-joining tree between our cohorts and other populations was constructed based on allele frequencies of HLA-A and HLA-B loci. We identified 58 HLA-A, 75 HLA-B, and 32 HLA-Cw distinct alleles from our cohort and no novel alleles. The frequency of HLA-B*5201 and A*0301 was significantly higher in the Han HIV-1 negative group. The frequency of HLA-B*5101 was significantly higher in the Uyghur HIV-1 negative group. We observed statistically significant increases in expectation-maximization (EM) algorithm predicted haplotype frequencies of HLA-A*0201-B*5101 in the Uyghur HIV-1 negative group, and of Cw*0304-B*4001 in the Han HIV-1 negative group. The B62s supertype frequency was found to be significantly higher in the Han HIV-1 negative group than in the Han HIV-1 positive group.
Conclusions
At the four-digit level, several HLA class I alleles and haplotypes were associated with lower HIV-1 susceptibility. Homogeneity of HLA class I and Bw4/Bw6 heterozygosity were not associated with HIV-1 susceptibility in our cohort. These observations contribute to the Chinese HLA database and could prove useful in the development of HIV-1 vaccine candidates.
doi:10.1371/journal.pone.0050656
PMCID: PMC3520934  PMID: 23251376
8.  Antiretroviral Drug Resistance Mutations Among Treated and Treatment-Naive Patients in Pakistan: Diversity of the HIV Type 1 pol Gene in Pakistan 
AIDS Research and Human Retroviruses  2011;27(12):1277-1282.
Abstract
Pakistan is experiencing a growing HIV epidemic. Antiretroviral drugs (ARV) have been smuggled into the country and available without prescription since the early 1990s, but are now provided free of cost by the government. We assessed the prevalence of HIV-1, drug resistance, and subtype distributions. Blood specimens were collected from HIV-1-infected participants registered in Sindh Province on dry blood spot (DBS) cards in 2008. Pol, protease, and partial reverse transcriptase regions were sequenced after reverse transcriptase PCR (RT-PCR). HIV-1 subtype was assigned by phylogenetic analysis. Primary drug resistance was analyzed by the Calibrated Population Resistance (CPR) tool using the Stanford Surveillance Drug Resistance Mutation (SDRM) major mutation list. Out of 100 blood samples collected, 42 were suitable for testing. Out of 42, 11 were ARV-receiving and 31 ARV-naive patients. Among them, 24 were injection drug users (IDUs), four immigrants, two hijras (male transvestites), two men who have sex with men (MSM), four prisoners, one female sex workers, two spouses of HIV-infected persons, and four from the general population. ARV resistance among naive patients was 2/31 (6.5%) and 36.4% (4/11) among ARV-experienced patients making an overall resistance of 14.2%. HIV-1 subtype A1 was the predominant subtype found in 35/42 (83.3%) followed by CRF35_AD and C, 6.5% each. Subtype D and G were found in one (2.4%) each. A significant proportion of Pakistani HIV patients has ARV drug resistance. Physicians treating patients should consider the magnitude of drug resistance while selecting regimens, and address drug adherence aggressively.
doi:10.1089/aid.2010.0324
PMCID: PMC3227241  PMID: 21591988
9.  Molecular cloned SHIV-CN97001: a Replication-Competent, R5 Simian-Human Immunodeficiency Virus Containing Env of a Primary Chinese HIV-1 Clade C isolate 
Journal of Medical Primatology  2011;40(6):427-436.
The increasing prevalence of human immunodeficiency virus type 1 (HIV-1) subtype C infection worldwide calls for efforts to develop a relevant animal model for evaluating AIDS candidate vaccines. In China, the prevalent HIV strains comprise a circulating recombinant form, BC (CRF07_BC), in which the envelope belongs to subtype C. To evaluate potential AIDS vaccines targeting Chinese viral strains in nonhuman primate models, we constructed a simian-human immunodeficiency virus (SHIV) carrying most of the envelope sequence of a primary HIV-1 clade C strain isolated from an HIV-positive intravenous drug user from YunNan province in China. Infection of six Chinese rhesus macaques with SHIV-CN97001 resulted in a low level of viremia and no significant alteration in CD4+ T-lymphocyte counts. To determine whether in vivo adaptation would enhance the infectivity of SHIV-CN97001, the parental infectious strain was serially passaged through eight Chinese rhesus macaques. The hallmarks of SHIV infectivity developed gradually, as shown by the increasingly elevated peak viremia with each passage. These findings establish that the R5-tropic SHIV-CN97001/Chinese rhesus macaque model should be very useful for evaluation of HIV-1 subtype C vaccines in China.
doi:10.1111/j.1600-0684.2011.00497.x
PMCID: PMC3389047  PMID: 21895680
Clade C; Passage; Rhesus macaques; SHIV
10.  HIV incidence among men who have sex with men in Beijing: a prospective cohort study 
BMJ Open  2012;2(6):e001829.
Objectives
(1) To assess the HIV incidence rate among men who have sex with men (MSM) in a large cohort study in Beijing, China and (2) to identify sociodemographic and behavioural risk factors of HIV seroconversion among MSM in Beijing, China.
Design
A prospective cohort study.
Setting
Baseline and follow-up visits were conducted among MSM in Beijing, China.
Participants
A cohort of 797 HIV-seronegative MSM was recruited from August to December 2009, with follow-up occurring after 6 and 12 months.
Primary and secondary outcome measures
At baseline and follow-up visits, participants reported sociodemographic and sexual behaviour information, and were tested for HIV, herpes simplex virus-2 (HSV-2) and syphilis with whole blood specimens. Cox regression analysis was used to identify factors associated with HIV seroconversion.
Results
Most study participants (86.8%) were retained by the 12-month follow-up. The HIV, HSV-2 and syphilis incidence rates were 8.09 (95% CI 6.92 to 9.26), 5.92 (95% CI 5.44 to 6.40) and 8.06 (95% CI 7.56 to 8.56) cases per 100 person-years, respectively. HIV seroconversion was significantly associated with being <25 years old, having <12 years of education, having >1 male sex partner in the past 6 months, and being syphilis positive or HSV-2 positive.
Conclusions
The HIV incidence among MSM in Beijing is serious. Interventions and treatment of sexually transmitted diseases (STD) should be combined with HIV control and prevention measures among MSM.
doi:10.1136/bmjopen-2012-001829
PMCID: PMC3533041  PMID: 23166133
Epidemiology
11.  The MSHA Strain of Pseudomonas Aeruginosa Activated TLR Pathway and Enhanced HIV-1 DNA Vaccine Immunoreactivity 
PLoS ONE  2012;7(10):e47724.
The mannose-sensitive hemagglutination pilus strain of Pseudomonas aeruginosa (PA-MSHA) has been shown to trigger naïve immune responses through the activation of monocytes, macrophages, natural killer cells (NK cells) and antigen presenting cells (APCs). Based on the hypothesis that PA-MSHA activates natural immunity through the Toll-like receptor (TLR) pathway, we scanned several critical TLR pathway molecules in mouse splenocytes using high-throughput real-time QRT-PCR and co-stimulatory molecule in bone marrow-derived dendritic cells (BMDCs) following in vitro stimulation by PA-MSHA. PA-MSHA enabled activation of the TLR pathway mediated by NF-κB and JNK signaling in splenocytes, and the co-stimulatory molecule CD86 was up-regulated in BMDCs. We then assessed the adjuvant effect of PA-MSHA for HIV-1 DNA vaccines. In comparison to DNA inoculation alone, co-inoculation with low dosage of PA-MSHA enhanced specific immunoreactivity against HIV-1 Env in both cellular and humoral responses, and promoted antibody avidity maturation. However, high doses of adjuvant resulted in an immunosuppressive effect; a two- or three-inoculation regimen yielded low antibody responses and the two-inoculation regimen exhibited only a slight cellular immunity response. To our knowledge, this is the first report demonstrating the utility of PA-MSHA as an adjuvant to a DNA vaccine. Further research is needed to investigate the exact mechanisms through which PA-MSHA achieves its adjuvant effects on innate immune responses, especially on dendritic cells.
doi:10.1371/journal.pone.0047724
PMCID: PMC3471878  PMID: 23077664
12.  A Comprehensive Mapping of HIV-1 Genotypes in Various Risk Groups and Regions across China Based on a Nationwide Molecular Epidemiologic Survey 
PLoS ONE  2012;7(10):e47289.
Background
China is experiencing a dynamic HIV/AIDS epidemic. While serology based surveillance systems have reported the spread of HIV/AIDS, detailed tracking of its transmission in populations and regions is not possible without mapping it at the molecular level. We therefore conducted a nationwide molecular epidemiology survey across the country.
Methods
HIV-1 genotypes were determined from 1,408 HIV-positive persons newly diagnosed in 2006. The prevalence of each genotype was estimated by weighting the genotype’s prevalence from each province- and risk-specific subpopulation with the number of reported cases in the corresponding subgroups in that year.
Results
CRF07_BC (35.5%), CRF01_AE (27.6%), CRF08_BC (20.1%), and subtype B' (9.6%) were the four main HIV-1 strains in China. CRF07_BC and CRF08_BC were the primary drivers of infection among injecting drug users in northeastern and southeastern China, respectively, and subtype B' remained dominant among former plasma donors in central China. In contrast, all four strains occurred in significant proportions among heterosexuals nationwide, pointing to an expansion of the HIV-1 epidemic from high-risk populations into the general population. CRF01_AE also replaced subtype B as the principal driver of infection among men-who-have-sex-with-men.
Conclusions
Our study provides the first comprehensive baseline data on the diversity and characteristics of HIV/AIDS epidemic in China, reflecting unique region- and risk group-specific transmission dynamics. The results provide information critical for designing effective prevention measures against HIV transmission.
doi:10.1371/journal.pone.0047289
PMCID: PMC3466245  PMID: 23056619
13.  Participation of HIV prevention programs among men who have sex with men in two cities of China—a mixed method study 
BMC Public Health  2012;12:847.
Background
Although various HIV prevention programs targeting men who have sex with men (MSM) are operating in China, whether and how these programs are being utilized is unclear. This study explores participation of HIV prevention programs and influencing factors among MSM in two cities in China.
Methods
This is a mixed-method study conducted in Beijing and Chongqing. A qualitative study consisting of in-depth interviews with 54 MSM, 11 key informants, and 8 focus group discussions, a cross-sectional survey using respondent-driven sampling among 998 MSM were conducted in 2009 and 2010 respectively to elicit information on MSM’s perception and utilization of HIV prevention programs. Qualitative findings were integrated with quantitative multivariate factors to explain the quantitative findings.
Results
Fifty-six percent of MSM in Chongqing and 75.1% in Beijing ever participated in at least one type of HIV prevention program (P=0.001). Factors related to participation in HIV prevention programs included age, ethnicity, income, HIV risk perception, living with boyfriend, living in urban area, size of MSM social network, having talked about HIV status with partners, and knowing someone who is HIV positive. Reasons why MSM did not participate in HIV prevention programs included logistical concerns like limited time for participation and distance to services; program content and delivery issues such as perceived low quality services and distrust of providers; and, cultural issues like HIV-related stigma and low risk perception.
Conclusions
The study shows that there is much room for improvement in reaching MSM in China. HIV prevention programs targeting MSM in China may need to be more comprehensive and incorporate the cultural, logistic and HIV-related needs of the population in order to effectively reach and affect this population’s risk for HIV.
doi:10.1186/1471-2458-12-847
PMCID: PMC3570394  PMID: 23039880
MSM; HIV prevention programs; Utilization; Participation; China
14.  The prevalence of transmitted antiretroviral drug resistance in treatment naïve HIV-infected individuals in China 
Background
Transmission of HIV drug resistance (TDR) gives rise to reduced efficacy of initial antiretroviral treatment, and has become a public health concern.
Methods
A nationwide survey on TDR was conducted in antiretroviral therapy naïve HIV-1 infected individuals from September 2004 to October 2005 in China. Drug resistance genotyping was performed on subjects’ plasma samples. Drug resistance mutations were determined and scored by Stanford HIV Drug Resistance algorithm.
Results
Sequences were obtained from 676 individuals, of which 61.2% were former plasma and blood donors, 17.3% were infected sexually, and 17.2% were intravenous drug users. Subtype B’ HIV-1 strains were found in 73.5%, CRF01_AE in 13.9%, CRF07_BC in 6.2%, CRF08_BC in 2.7%, subtype C in 1.04%, subtype B in 0.9%, CRF02_AG in 0.4% and B’/C intersubtype recombinant strains in 1.3% of the subjects. Twenty-six (3.8%) were found to harbor drug resistance strains. The rates of resistance to PIs, NRTIs and NNRTIs were 0.4%, 1.6% and 2.1%, respectively. Though there was no significant difference in TDR rates between 2004 and 2005 (2.9% vs. 4.4%), an increased trend was observed in the rate of high-level drug resistance (0.8% in 2004 vs. 3.0% in 2005, P = 0.0634).
Conclusions
The rate of TDR was relatively low in China, as compared with those in developed countries. Surveys among recently HIV-infected subjects should be preformed continually to ensure the success of the scale-up antiretroviral treatment.
doi:10.1097/QAI.0b013e3181c7d363
PMCID: PMC3422681  PMID: 20104099
treatment naïve; transmitted HIV-1 drug resistance; prevalence
15.  The Molecular Mechanism of Action of the CR6261-Azichromycin Combination Found through Computational Analysis 
PLoS ONE  2012;7(5):e37790.
Background
CR6261 was found in 2008 and F10 was found in 2009. In 2010 Friesen et al experimentally showed that Oseltamivir/Zanamivir may improve the therapeutic efficacy of CR6261. As a result, the use of CR6261 combined with a drug to provide an antibody-based therapy against all influenza A viruses was proposed. Although CR8020 may neutralize group 2 influenza viruses and FI6 may neutralize both group 1 and group 2 influenza viruses as determined in 2011, the insight of Friesen et al is still interesting. Here, we address the following questions: how to uncover the molecular mechanism of a drug, which improves the therapeutic efficacy of mAbs and how to find drugs that enable CR6261 (CR8020, F10) to become a universal mAb.
Methods and Findings
Using the 3D structures of 3 gbn, 3 gbm, 3 ztn, 3 ztj, 3 fku and 3 sdy, we separate the 3D structures of CR6261, F10, CR8020 and FI6, and the 3D structures of trimer HAs of H3N2 and H5N1. Based on the experimental result of Friesen et al, we have found many clues, which reveal the molecular mechanism of action for a drug and an HA-mAb complex.
Conclusions
Oseltamivir/Zanamivir may congruously improve the therapeutic efficacies of CR6261, F10, CR8020 and FI6 by providing an additional affinity to compensate for the loss of affinity between HA and mAb resulting from mutations. However, Oseltamivir or Zanamivir are not expected to generally widen the spectrum of these mAbs. In order to enhance CR6261, CR8020, or for F10 to become universal, we may select Azichromycin, Oseltamivir, or the combination of Azichromycin and Oseltamivir, respectively.
doi:10.1371/journal.pone.0037790
PMCID: PMC3365099  PMID: 22693576
16.  Predictors of HIV and Syphilis among Men Who Have Sex with Men in a Chinese Metropolitan City: Comparison of Risks among Students and Non-Students 
PLoS ONE  2012;7(5):e37211.
Background
Men who have sex with men (MSM) are at a substantial risk of HIV, given rising HIV prevalence in urban China. Adolescent and adult students often take HIV-related risk as part of sexual exploration. We compared the risks of HIV and syphilis infections and risky sexual behaviors between student and non-student among urban MSM.
Methods
Respondent driven sampling approach was used to recruit men who were self-identified as MSM in Chongqing Metropolitan City in southwestern China in 2009. Each participant completed a computer-assisted self-interview which collected demographic and behavioral data, and provided blood specimens for HIV and syphilis testing. Multivariable logistic regression analyses identified predictors for HIV and syphilis infections while comparing student and non-student MSM.
Results
Among 503 MSM participants, 36.4% were students, of whom 84.2% were in college. The adjusted prevalence of HIV infection was 5.5% (95% confidence interval [CI]: 2.1%–10.2%) in students and 20.9% (95% CI: 13.7%–27.5%) in non-students; the adjusted prevalence of syphilis was 4.4% (95% CI: 0.7%–9.0%) in students and 7.9% (95% CI: 3.6%–12.9%) in non-students (P = 0.12). Two groups had similar risky sexual behaviors such as number of sexual partners and exchanging sex for money. Multivariate analysis showed that students had lower HIV prevalence than non-students (adjusted odds ratio [AOR]: 0.3; 95% CI: 0.1–0.8) adjusting for age, ethnicity and other variables.
Conclusion
Student MSM have lower HIV and similar syphilis prevalence compared with non-student MSM. However, due to a shorter duration of sexual experience and high prevalence of at-risk sexual behaviors among student MSM, HIV risk might be quite high in students as in non-students.
doi:10.1371/journal.pone.0037211
PMCID: PMC3356386  PMID: 22623994
17.  Computable Features Required to Evaluate the Efficacy of Drugs and a Universal Algorithm to Find Optimally Effective Drug in a Drug Complex 
PLoS ONE  2012;7(3):e33709.
Background
The H1N1 pandemic in 2009 and the H5N1 pandemic in 2005 demonstrated that the drugs approved to treat influenza A viruses have low efficacy. This provided a stimulus for new studies of influenza A viruses in the context of the methods used in drug design developed over the past 100 years. Finding new universal drugs is the ultimate goal but its long time horizon is incompatible with emergency situations created by reoccurring influenza outbreaks. Therefore, we propose a computer-aided method for finding efficacious drugs and drug complexes based on the use of the DrugBank database.
Methods
(1) We start by assembling a panel of target proteins. (2) We then assemble a panel of drugs. (3) This is followed by a selection of benchmark binding pockets based on the panel of target proteins and the panel of drugs. (4) We generate a set of computational features, which measure the efficacy of a drug. (5) We propose a universal program to search for drugs and drug complexes. (6) A case study we report here illustrates how to use this universal program for finding an optimal drug and a drug complex for a given target. (7) Validation of the Azirchromycin and Aspirin complex is provided mathematically. (8) Finally, we propose a simple strategy to validate our computational prediction that the Azirchromycin and Aspirin complex should prove clinically effective.
Result
A set of computable features are mined and then based on these features, a universal program for finding the potential drug &drug complexes is proposed. Using this universal program, the Azirchromycin and Aspirin complex is selected and its efficacy is predicted mathematically. For clinical validation of this finding, future work is still required.
doi:10.1371/journal.pone.0033709
PMCID: PMC3311648  PMID: 22457784
18.  The HIV-1 Epidemic: Low- to Middle-Income Countries 
Low- to middle-income countries bear the overwhelming burden of the human immunodeficiency virus type 1 (HIV-1) epidemic in terms of the numbers of their citizens living with HIV/AIDS (acquired immunodeficiency syndrome), the high degrees of viral diversity often involving multiple HIV-1 clades circulating within their populations, and the social and economic factors that compromise current control measures. Distinct epidemics have emerged in different geographical areas. These epidemics differ in their severity, the population groups they affect, their associated risk behaviors, and the viral strains that drive them. In addition to inflicting great human cost, the high burden of HIV infection has a major impact on the social and economic development of many low- to middle-income countries. Furthermore, the high degrees of viral diversity associated with multiclade HIV epidemics impacts viral diagnosis and pathogenicity and treatment and poses daunting challenges for effective vaccine development.
A human immunodeficiency type 1 vaccine may be the most effective method of controlling the acquired immunodeficiency syndrome pandemic. However, the higher degrees of viral diversity in lower-income countries may undermine vaccine development efforts.
doi:10.1101/cshperspect.a007187
PMCID: PMC3282497  PMID: 22393534
19.  Factors Associated with Recent Risky Drug Use and Sexual Behaviors among Drug Users in Southwestern China 
Journal of AIDS & clinical research  2011;2(120):2155-6113-2-120.
A cross-sectional survey was conducted in 2007 among 504 drug users who were recruited mainly from detoxification centers in southwest China. About one-third (34.3%) of participants reported recent risky drug use behavior, which was defined as injecting drugs in the past 3 months, and more than one-fifth (21.6%) reported recent risky sexual behavior, or had multiple sexual partners in the past 30 days. Male sex (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.2–3.2) and more episodes of detoxification (OR, 3.7; 95% CI, 2.3–6.0) were associated with higher odds of risky drug use behavior, while unmarried status (OR, 1.7; 95% CI, 1.0–2.9), higher personal annual income (OR, 1.8; 95% CI, 1.1–2.8) and history of sexually transmitted infections (OR, 3.7; 95% CI, 2.1–6.6) were associated with higher odds of having risky sexual behavior. Subgroup analyses showed 15% participants who used drugs in the past 3 months also shared needles, and 77% participants who had multiple sexual partners in the past 30 days did not use condoms during sex with non-primary sexual partners. The study findings are useful for developing HIV risk reduction intervention programs among drug users.
doi:10.4172/2155-6113.1000120
PMCID: PMC3238800  PMID: 22180851
HIV; Drug use; Sexual behavior; China
20.  Correlates of Incident Infections for HIV, Syphilis, and Hepatitis B Virus in A Cohort of Men Who Have Sex with Men in Beijing 
AIDS Patient Care and STDs  2010;24(9):595-602.
Abstract
Recent data suggest that the prevalence of HIV/syphilis infections among men who have sex with men (MSM) in China increased rapidly. This cohort study was to assess the correlates of the incident infections for HIV, syphilis, and hepatitis B virus (HBV) among sexually active and HIV–negative MSM in China. A cohort of 507 HIV-seronegative MSM was recruited from November 2006 to February 2007. Sociodemographics, sexual and drug use behaviors, uptake of HIV-prevention services, and HIV, syphilis, and HBV seroconversions were assessed at 6- and 12- month follow-up. The incidence rates were 2.6 per 100 person-years for HIV, 16.9 per 100 person-years for syphilis, and 3.3 per 100 person-years for HBV. Multivariate Cox regression analyses showed that syphilis infection (hazard ratio [HR] = 3.6; 95% confidence interval [CI]: 1.1–11.6) and no perceived risk of HIV infection (HR = 6.0; 95% CI: 1.6–22.7) were independently associated with HIV seroconversion. Predictors for syphilis seroconversion included less education (HR = 1.87; 95% CI: 1.1–3.3), found male sex partners through bathhouses/public washrooms/parks (HR = 2.19; 95% CI: 1.2–4.0), drank alcohol 4 or more times monthly (HR = 1.95; 95% CI: 1.1–3.6), and had sexually transmitted diseases (HR = 2.65; 95% CI: 1.5–4.5). The only predictor for incident HBV seroconvension was having more male sex partners in the past 3 months (HR = 11.8; 95% CI: 1.5–90.4). Alarmingly high incidence rates of HIV, syphilis, and HBV were found among MSM concurrently with high prevalent risky behaviors and low uptakes of health care services. The findings of this study underscore the urgent needs for a comprehensive intervention strategy to curtail the rapid spread of HIV, syphilis, and HBV.
doi:10.1089/apc.2010.0083
PMCID: PMC2957630  PMID: 20731610
22.  Potent and Broad Anti-HIV-1 Activity Exhibited by a Glycosyl-Phosphatidylinositol-Anchored Peptide Derived from the CDR H3 of Broadly Neutralizing Antibody PG16▿†‡ 
Journal of Virology  2011;85(17):8467-8476.
PG9 and PG16 are two recently isolated quaternary-specific human monoclonal antibodies that neutralize 70 to 80% of circulating HIV-1 isolates. The crystal structure of PG16 shows that it contains an exceptionally long CDR H3 that forms a unique stable subdomain that towers above the antibody surface to confer fine specificity. To determine whether this unique architecture of CDR H3 itself is sufficient for epitope recognition and neutralization, we cloned CDR H3 subdomains derived from human monoclonal antibodies PG16, PG9, b12, E51, and AVF and genetically linked them to a glycosyl-phosphatidylinositol (GPI) attachment signal. Each fusion gene construct is expressed and targeted to lipid rafts of plasma membranes through a GPI anchor. Moreover, GPI-CDR H3(PG16, PG9, and E51), but not GPI-CDR H3(b12 and AVF), specifically neutralized multiple clades of HIV-1 isolates with a great degree of potency when expressed on the surface of transduced TZM-bl cells. Furthermore, GPI-anchored CDR H3(PG16), but not GPI-anchored CDR H3(AVF), specifically confers resistance to HIV-1 infection when expressed on the surface of transduced human CD4+ T cells. Finally, the CDR H3 mutations (Y100HF, D100IA, and G7) that were previously shown to compromise the neutralization activity of antibody PG16 also abolished the neutralization activity of GPI-CDR H3(PG16). Thus, we conclude that the CDR H3 subdomain of PG16 neutralizes HIV-1 when targeted to the lipid raft of the plasma membrane of HIV-1-susceptible cells and that GPI-CDR H3 can be an alternative approach for determining whether the CDR H3 of certain antibodies alone can exert epitope recognition and neutralization.
doi:10.1128/JVI.00520-11
PMCID: PMC3165811  PMID: 21715497
23.  Inhibitory activity of 9-phenylcyclohepta[d]pyrimidinedione derivatives against different strains of HIV-1 as non-nucleoside reverse transcriptase inhibitors 
Virology Journal  2011;8:230.
Background
The non-nucleoside reverse transcriptase inhibitor (NNRTI), as a major component of the highly active antiretroviral therapy (HAART) to HIV-1 (human immunodeficiency virus type 1) infected patients, required the development of new NNRTIs with improved resistance profile and decreased toxicity. Therefore, a series of novel compounds, 9-phenylcyclohepta[d]pyrimidinedione derivatives (PCPs), were designed based on the chemical structure of TNK-651, to detect anti-HIV-1 activity.
Results
1-[(benzyloxy)methyl]-9-phenyl-cyclohepta[d] pyrimidinedione (BmPCP) among four PCPs has antiviral activity on laboratory-adapted HIV strains (HIV-1 SF33). The results showed 50% inhibition concentrations (IC50s) of BmPCP were 0.34 μM, 1.72 μM and 1.96 μM on TZM-bl, peripheral blood mononuclear cells (PBMCs) and MT4, respectively. It was also effective against infection by the predominant HIV-1 isolates in China, with IC50s at low μM levels. Its selectivity index (SI) ranged from 67 to 266 in different cells. The results of time-of-addition assay demonstrated that BmPCP inhibited HIV-1 infection by targeting the post entry of the HIV-1 replication cycle. For inhibition of HIV-1 reverse transcriptase activity, the IC50 values of BmPCP and NVP were 1.51 and 3.67 μM, respectively.
Conclusions
BmPCP with a novel structure acts as a NNRTI to inhibit HIV-1 replication and can serve as a lead compound for further development of new anti-HIV-1 drugs.
doi:10.1186/1743-422X-8-230
PMCID: PMC3121703  PMID: 21569631
24.  Susceptibility of HIV-1 Subtypes B′, CRF07_BC and CRF01_AE that Are Predominantly Circulating in China to HIV-1 Entry Inhibitors 
PLoS ONE  2011;6(3):e17605.
Background
The B′, CRF07_BC and CRF01_AE are the predominant HIV-1 subtypes in China. It is essential to determine their baseline susceptibility to HIV entry inhibitors before these drugs are used in China.
Methodology/Principal Findings
The baseline susceptibility of 14 representative HIV-1 isolates (5 CRF07_BC, 4 CRF01_AE, and 5 B′), most of which were R5 viruses, obtained from drug-naïve patients to HIV entry inhibitors, including two fusion inhibitors (enfuvirtide and C34), two CCR5 antagonists (maraviroc and TAK779) and one CXCR4 antagonist (AMD3100), were determined by virus inhibition assay. The sequences of their env genes were amplified and analyzed. These isolates possessed similar susceptibility to C34, but they exhibited different sensitivity to enfuvirtide, maraviroc or TAK779. CRF07_BC isolates, which carried polymorphisms of A578T and V583I in the N-terminal heptad repeat and E630Q, E662A, K665S, A667K and S668N in the C-terminal heptad repeat of gp41, were about 5-fold less sensitive than B′ and CRF01_AE isolates to enfuvirtide. Subtype B′ isolates with a unique polymorphism site of F317W in V3 loop, were about 4- to 5-fold more sensitive than CRF07_BC and CRF01_AE isolates to maraviroc and TAK779. AMD3100 at the concentration as high as 5 µM exhibited no significant inhibitory activity against any of the isolates tested.
Conclusion
Our results suggest that there are significant differences in baseline susceptibility to HIV entry inhibitors among the predominant HIV-1 subtypes in China and the differences may partly result from the naturally occurring polymorphisms in these subtypes. This study provides useful information for rational design of optimal therapeutic regimens for HIV-1-infected patients in China.
doi:10.1371/journal.pone.0017605
PMCID: PMC3055885  PMID: 21412427
25.  Co-receptor usage and prediction of v3 genotyping algorithms in hiv-1 subtype b' from paid blood donors experienced anti-retroviral therapy in chinese central province 
Virology Journal  2010;7:280.
Background
This study explored co-receptor usage and prediction of V3 genotyping algorithms in HIV-1 subtype B' from paid blood donors experienced anti-retroviral therapy in Chinese central province in order to design effectively therapeutic regimen.
Methods
HIV-1 strains were isolated in treatment HIV-1 infections and treatment-naïve HIV-1 infections, then co-receptor usage of HIV-1 strains was identified based on Ghost cell lines using flow cytometry. HIV-1 V3 region was amplified and submitted into web-server (WebPSSM and geno2pheno) to predict HIV-1 co-receptor usage. The feasibility of prediction HIV-1 usage with Web-server assay was analyzed by comparing prediction of V3 genotyping algorithms with HIV phenotype assay based on Ghost cell line.
Results
45 HIV-1 strains and 114 HIV-1 strains were isolated from HIV-1 infections exposed anti-retroviral therapy and treatment-naïve, respectively. 41% clinical viruses from ART patients and 18% from treatment-naïve patients used CXCR4 as co-receptor. The net charge in the V3 loop was significantly difference in both groups. The sensitivity and specificity for predicting co-receptor capacity is 54.6% and 90.0% on 11/25 rule, 50.0% and 90% on Web-PSSMx4r5, 68.2% and 40.0% on Geno2pheno[co-receptor].
Conclusion
Dual/mixed/X4 co-receptor utilization was higher in ART patients than treatment-naïve patients. It is should paid attention to predicting HIV-1 co-receptor usage based on V3 genotyping algorithms in HIV-1 subtype B' from paid blood donors experienced anti-retroviral therapy in Chinese central province.
doi:10.1186/1743-422X-7-280
PMCID: PMC2988017  PMID: 20969781

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