PubTransformer

A site to transform Pubmed publications into these bibliographic reference formats: ADS, BibTeX, EndNote, ISI used by the Web of Knowledge, RIS, MEDLINE, Microsoft's Word 2007 XML.

barrier method against HIV - Top 30 Publications

Microwave & magnetic proteomics of macrophages from patients with HIV-associated cognitive impairment.

HIV-infected monocytes can infiltrate the blood brain barrier as differentiated macrophages to the central nervous system, becoming the primary source of viral and cellular neurotoxins. The final outcome is HIV-associated cognitive impairment (HACI), which remain prevalent today, possibly due to the longer life-span of the patients treated with combined anti-retroviral therapy. Our main goal was to characterize the proteome of monocyte-derived macrophages (MDM) from HACI patients, and its association with their cognitive status, to find novel targets for therapy.

Randomized, double-blind, placebo-controlled clinical trial to assess the safety and effectiveness of a novel dual-action oral topical formulation against upper respiratory infections.

Current prevention options for upper respiratory infections (URIs) are not optimal. We conducted a randomized, double-blinded, placebo-controlled pilot clinical trial to evaluate the safety and efficacy of ARMS-I™ (currently marketed as Halo™) in the prevention of URIs.

Medroxyprogesterone acetate and levonorgestrel increase genital mucosal permeability and enhance susceptibility to genital herpes simplex virus type 2 infection.

Depot-medroxyprogesterone acetate (DMPA) is a hormonal contraceptive especially popular in areas with high prevalence of HIV and other sexually transmitted infections (STI). Although observational studies identify DMPA as an important STI risk factor, mechanisms underlying this connection are undefined. Levonorgestrel (LNG) is another progestin used for hormonal contraception, but its effect on STI susceptibility is much less explored. Using a mouse model of genital herpes simplex virus type 2 (HSV-2) infection, we herein found that DMPA and LNG similarly reduced genital expression of the desmosomal cadherin desmoglein-1α (DSG1α), enhanced access of inflammatory cells to genital tissue by increasing mucosal epithelial permeability, and increased susceptibility to viral infection. Additional studies with uninfected mice revealed that DMPA-mediated increases in mucosal permeability promoted tissue inflammation by facilitating endogenous vaginal microbiota invasion. Conversely, concomitant treatment of mice with DMPA and intravaginal estrogen restored mucosal barrier function and prevented HSV-2 infection. Evaluating ectocervical biopsy tissue from women before and 1 month after initiating DMPA remarkably revealed that inflammation and barrier protection were altered by treatment identically to changes seen in progestin-treated mice. Together, our work reveals DMPA and LNG diminish the genital mucosal barrier; a first-line defense against all STI, but may offer foundation for new contraceptive strategies less compromising of barrier protection.

Effect of Physical Violence on Sexually Transmitted Infections and Treatment Seeking Behaviour among Female Sex Workers in Thane District, Maharashtra, India.

Violence against sex workers can heighten their vulnerability to HIV and other sexually transmitted infections (STIs). Evidence suggests the risk of acquiring STI/HIV infections among female sex workers (FSWs) who have experienced violence to be almost three-times higher than FSWs, who have not experienced violence. Moreover, an experience of physical and sexual violence makes it difficult for them to negotiate safer sex with their partners and often act as a barrier to utilization of prevention services.

The Contribution of Cervicovaginal Infections to the Immunomodulatory Effects of Hormonal Contraception.

Particular types of hormonal contraceptives (HCs) and genital tract infections have been independently associated with risk of HIV-1 acquisition. We examined whether immunity in women using injectable depot medroxyprogesterone acetate (DMPA), combined oral contraceptives (COC), or no HCs differs by the presence of cervicovaginal infections. Immune mediators were quantified in cervical swabs from 832 HIV-uninfected reproductive-age Ugandans and Zimbabweans. Bacterial infections and HIV were diagnosed by PCR, genital herpes serostatus by enzyme-linked immunosorbent assay (ELISA), altered microflora by Nugent score, and Trichomonas vaginalis and Candida albicans infection by wet mount. Generalized linear models utilizing Box-Cox-Power transformation examined associations between levels of mediators, infection status, and HCs. In no-HC users, T. vaginalis was associated with broadest spectrum of aberrant immunity (higher interleukin 1β [IL-1β], IL-8, macrophage inflammatory protein 3α [MIP-3α], β-defensin 2 [BD2], and IL-1 receptor antigen [IL-1RA]). In women with a normal Nugent score and no genital infection, compared to the no-HC group, COC users showed higher levels of IL-1β, IL-6, IL-8, and IL-1RA, while DMPA users showed higher levels of RANTES and lower levels of BD2, both associated with HIV seroconversion. These effects of COC were blunted in the presence of gonorrhea, chlamydia, trichomoniasis, candidiasis, and an abnormal Nugent score; however, RANTES was increased among COC users with herpes, chlamydia, and abnormal Nugent scores. The effect of DMPA was exacerbated by lower levels of IL-1RA in gonorrhea, chlamydia, or herpes, SLPI in gonorrhea, and IL-1β, MIP-3α, and IL-1RA/IL1β ratio in trichomoniasis. Thus, the effects of HC on cervical immunity depend on the genital tract microenvironment, and a weakened mucosal barrier against HIV may be a combined resultant of genital tract infections and HC use.

Competition is not necessarily a barrier to community mobilisation among sex workers: an intervention planning assessment from Zimbabwe.

Community mobilization among female sex workers (SWs) is recognized as an effective strategy to empower SWs and increase their uptake of health services. Activities focus on increasing social cohesion between SWs by building trust, strengthening networks, and encouraging shared efforts for mutual gain. Several studies, however, suggest that high levels of interpersonal competition between SWs can pose a barrier to collective action and support. We conducted a study to examine levels of perceived competition between SWs in Mutare, Hwange and Victoria Falls in Zimbabwe in order to inform development of a community-based intervention for HIV prevention and treatment. This paper focuses on our qualitative findings and their implications for the design of HIV programming in the Zimbabwean context.

Vpx mediated degradation of SAMHD1 has only a very limited effect on lentiviral transduction rate in ex vivo cultured HSPCs.

Understanding how to achieve efficient transduction of hematopoietic stem and progenitor cells (HSPCs), while preserving their long-term ability to self-reproduce, is key for applying lentiviral-based gene engineering methods. SAMHD1 is an HIV-1 restriction factor in myeloid and resting CD4+ T cells that interferes with reverse transcription by decreasing the nucleotide pools or by its RNase activity. Here we show that SAMHD1 is expressed at high levels in HSPCs cultured in a medium enriched with cytokines. Thus, we hypothesized that degrading SAMHD1 in HSPCs would result in more efficient lentiviral transduction rates. We used viral like particles (VLPs) containing Vpx, shRNA against SAMHD1, or provided an excess of dNTPs or dNs to study this question. Regardless of the method applied, we saw no increase in the lentiviral transduction rate. The result was different when we used viruses (HR-GFP-Vpx+) which carry Vpx and encode GFP. These viruses allow assessment of the effects of Vpx specifically in the transduced cells. Using HR-GFP-Vpx+ viruses, we observed a modest but significant increase in the transduction efficiency. These data suggest that SAMHD1 has some limited efficacy in blocking reverse transcription but the major barrier for efficient lentiviral transduction occurs before reverse transcription.

The condom: A turbulent history.

The literature concerning the history of condoms is replete with errors. The paper Youssef published in 1993 is in our opinion the best. We update and expand the information.

Efficacy, but not antibody titer or affinity, of a heroin hapten conjugate vaccine correlates with increasing hapten densities on tetanus toxoid, but not on CRM197 carriers.

Vaccines against drugs of abuse have induced antibodies in animals that blocked the biological effects of the drug by sequestering the drug in the blood and preventing it from crossing the blood-brain barrier. Drugs of abuse are too small to induce antibodies and, therefore, require conjugation of drug hapten analogs to a carrier protein. The efficacy of these conjugate vaccines depends on several factors including hapten design, coupling strategy, hapten density, carrier protein selection, and vaccine adjuvant. Previously, we have shown that 1 (MorHap), a heroin/morphine hapten, conjugated to tetanus toxoid (TT) and mixed with liposomes containing monophosphoryl lipid A [L(MPLA)] as adjuvant, partially blocked the antinociceptive effects of heroin in mice. Herein, we extended those findings, demonstrating greatly improved vaccine induced antinociceptive effects up to 3% mean maximal potential effect (%MPE). This was obtained by evaluating the effects of vaccine efficacy of hapten 1 vaccine conjugates with varying hapten densities using two different commonly used carrier proteins, TT and cross-reactive material 197 (CRM197). Immunization of mice with these conjugates mixed with L(MPLA) induced very high anti-1 IgG peak levels of 400-1500 μg/mL that bound to both heroin and its metabolites, 6-acetylmorphine and morphine. Except for the lowest hapten density for each carrier, the antibody titers and affinity were independent of hapten density. The TT carrier based vaccines induced long-lived inhibition of heroin-induced antinociception that correlated with increasing hapten density. The best formulation contained TT with the highest hapten density of ≥30 haptens/TT molecule and induced %MPE of approximately 3% after heroin challenge. In contrast, the best formulation using CRM197 was with intermediate 1 densities (10-15 haptens/CRM197 molecule), but the %MPE was approximately 13%. In addition, the chemical synthesis of 1, the optimization of the conjugation method, and the methods for the accurate quantification of hapten density are described.

Consistent condom use in HIV/AIDS patients receiving antiretroviral therapy in northwestern Ethiopia: implication to reduce transmission and multiple infections.

Human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) is one of the greatest public health problems of sub-Saharan African countries. Consistent condom use, among others, remains the most effective barrier method against HIV transmission. However, existing reports on frequency of consistent condom use have targeted the general public, rather than HIV/AIDS patients due, to the assumption that condom use is not important in HIV-infected persons. Since consistent condom use among HIV/AIDS patients is vital, to prevent the virus transmission from the infected to noninfected as well as to prevent multiple infections among already infected persons, its frequency and determining factors need to be investigated.

Integrating reproductive health services into HIV care: strategies for successful implementation in a low-resource HIV clinic in Lilongwe, Malawi.

Lighthouse Trust operates two public HIV testing, treatment and care clinics in Lilongwe, Malawi, caring for over 26 000 people living with HIV, 23 000 of whom are on antiretroviral treatment (ART). In August 2010, Lighthouse Trust piloted a step-wise integration of sexual and reproductive health (SRH) services into routine HIV care at its Lighthouse clinic site. The objectives were to increase uptake of family planning (FP), promote long-term reversible contraceptive methods, and increase access, screening and treatment for cervical cancer using visual inspection with acetic acid.

Progesterone-based intrauterine device use is associated with a thinner apical layer of the human ectocervical epithelium and a lower ZO-1 mRNA expression.

Currently, whether hormonal contraceptives affect male to female human immunodeficiency virus (HIV) transmission is being debated. In this study, we investigated whether the use of progesterone-based intrauterine devices (pIUDs) is associated with a thinning effect on the ectocervical squamous epithelium, down-regulation of epithelial junction proteins, and/or alteration of HIV target cell distribution in the human ectocervix. Ectocervical tissue biopsies from healthy premenopausal volunteers using pIUDs were collected and compared to biopsies obtained from two control groups, namely women using combined oral contraceptives (COCs) or who do not use hormonal contraceptives. In situ staining and image analysis were used to measure epithelial thickness and the presence of HIV receptors in tissue biopsies. Messenger RNA levels of epithelial junction markers were measured by quantitative PCR. The epithelial thickness displayed by women in the pIUD group was similar to those in the COC group, but significantly thinner as compared to women in the no hormonal contraceptive group. The thinner epithelial layer of the pIUD group was specific to the apical layer of the ectocervix. Furthermore, the pIUD group expressed significantly lower levels of the tight junction marker ZO-1 within the epithelium as compared to the COC group. Similar expression levels of HIV receptors and coreceptors CD4, CCR5, DC-SIGN, and Langerin were observed in the three study groups. Thus, women using pIUD displayed a thinner apical layer of the ectocervical epithelium and reduced ZO-1 expression as compared to control groups. These data suggest that pIUD use may weaken the ectocervical epithelial barrier against invading pathogens, including HIV.

Barrier methods for human immunodeficiency virus prevention.

Condoms remain the most effective barrier against the sexual transmission of the human immunodeficiency virus (HIV). Male condoms have proven to be 80% to 90% effective, and female condoms have similar results. Poor adherence and improper use limit their effectiveness. In addition to condoms, microbicides are a promising barrier against HIV transmission. More than 50 candidate topical microbicide compounds have undergone preclinical or clinical testing in the last 10 years, but there are currently no US Food and Drug Administration (FDA)-approved compounds. Rectal microbicides are also being developed, as anal receptive sex is an effective mode of HIV transmission.

Resistance mechanism of human immunodeficiency virus type-1 protease to inhibitors: A molecular dynamic approach.

Human immunodeficiency virus type 1 (HIV-1) protease inhibitors comprise an important class of drugs used in HIV treatments. However, mutations of protease genes accelerated by low fidelity of reverse transcriptase yield drug resistant mutants of reduced affinities for the inhibitors. This problem is considered to be a serious barrier against HIV treatment for the foreseeable future. In this study, molecular dynamic simulation method was used to examine the combinational and additive effects of all known mutations involved in drug resistance against FDA approved inhibitors. Results showed that drug resistant mutations are not randomly distributed along the protease sequence; instead, they are localized on flexible or hot points of the protein chain. Substitution of more hydrophobic residues in flexible points of protease chains tends to increase the folding, lower the flexibility and decrease the active site area of the protease. The reduced affinities of HIV-1 protease for inhibitors seemed to be due to substantial decrease in the size of the active site and flap mobility. A correlation was found between the binding energy of inhibitors and their affinities for each mutant suggesting the distortion of the active site geometry in drug resistance by preventing effective fitting of inhibitors into the enzymes' active site. To overcome the problem of drug resistance of HIV-1 protease, designing inhibitors of variable functional groups and configurations is proposed.

Use of Condoms among Human Immunodeficiency Virus Positive Women Attending Antenatal Clinic in Nnewi, South East Nigeria.

Consistent use of condom provides protection from transmission of human immunodeficiency virus (HIV) infection in couples with sero-discordant HIV status. It also protects against acquiring other strains in HIV positive concordant couples.

The inner foreskin of healthy males at risk of HIV infection harbors epithelial CD4+ CCR5+ cells and has features of an inflamed epidermal barrier.

Male circumcision provides partial protection against multiple sexually transmitted infections (STIs), including HIV, but the mechanisms are not fully understood. To examine potential vulnerabilities in foreskin epithelial structure, we used Wilcoxon paired tests adjusted using the false discovery rate method to compare inner and outer foreskin samples from 20 healthy, sexually active Peruvian males who have sex with males or transgender females, ages 21-29, at elevated risk of HIV infection. No evidence of epithelial microtrauma was identified, as assessed by keratinocyte activation, fibronectin deposition, or parakeratosis. However, multiple suprabasal tight junction differences were identified: 1) inner foreskin stratum corneum was thinner than outer (p = 0.035); 2) claudin 1 had extended membrane-bound localization throughout inner epidermis stratum spinosum (p = 0.035); 3) membrane-bound claudin 4 was absent from inner foreskin stratum granulosum (p = 0.035); and 4) occludin had increased membrane deposition in inner foreskin stratum granulosum (p = 0.042) versus outer. Together, this suggests subclinical inflammation and paracellular transport modifications to the inner foreskin. A setting of inflammation was further supported by inner foreskin epithelial explant cultures secreting higher levels of GM-CSF (p = 0.029), IP-10 (p = 0.035) and RANTES (p = 0.022) than outer foreskin, and also containing an increased density of CCR5+ and CD4+ CCR5+ cells (p = 0.022). Inner foreskin dermis also secreted more RANTES than outer (p = 0.036), and had increased density of CCR5+ cells (p = 0.022). In conclusion, subclinical changes to the inner foreskin of sexually active males may support an inflammatory state, with availability of target cells for HIV infection and modifications to epidermal barriers, potentially explaining the benefits of circumcision for STI prevention.

Simultaneous prevention of unintended pregnancy and STIs: a challenging compromise.

Unintended pregnancy and sexually transmitted infections (STIs) are the major negative consequences of unsafe sex. Both are common and have long-term social and health consequences. Barrier methods of contraception can prevent both, but unfortunately they are much less effective than the more modern methods at pregnancy prevention. Modern effective contraceptives, however, do not protect against STIs and some may increase the risk of acquisition of infection. This comprehensive review discusses the magnitude of burden of reproductive ill-health, focussing on data from the European region, and explores the relationship between contraceptive use and STIs.

Behavioral interventions for improving dual-method contraceptive use.

Dual-method contraception refers to using condoms as well as another modern method of contraception. The latter (usually non-barrier) method is commonly hormonal (e.g., oral contraceptives) or a non-hormonal intrauterine device. Use of two methods can better prevent pregnancy and the transmission of HIV and other sexually transmitted infections (STIs) compared to single-method use. Unprotected sex increases risk for disease, disability, and mortality in many areas due to the prevalence and incidence of HIV/STI. Millions of women, especially in lower-resource areas, also have an unmet need for protection against unintended pregnancy.

Systemic immune activation in HIV and potential therapeutic options.

Advancement in HIV treatment has evolved over the last two decades with the discovery of new drugs and approaches. Studies have demonstrated that HIV-infected individuals have elevated immune activation even during effective antiretroviral therapy. Persistently elevated immune activation has been one of the main obstacles against developing an effective approach for curing HIV.

Drug-eluting fibers for HIV-1 inhibition and contraception.

Multipurpose prevention technologies (MPTs) that simultaneously prevent sexually transmitted infections (STIs) and unintended pregnancy are a global health priority. Combining chemical and physical barriers offers the greatest potential to design effective MPTs, but integrating both functional modalities into a single device has been challenging. Here we show that drug-eluting fiber meshes designed for topical drug delivery can function as a combination chemical and physical barrier MPT. Using FDA-approved polymers, we fabricated nanofiber meshes with tunable fiber size and controlled degradation kinetics that facilitate simultaneous release of multiple agents against HIV-1, HSV-2, and sperm. We observed that drug-loaded meshes inhibited HIV-1 infection in vitro and physically obstructed sperm penetration. Furthermore, we report on a previously unknown activity of glycerol monolaurate (GML) to potently inhibit sperm motility and viability. The application of drug-eluting nanofibers for HIV-1 prevention and sperm inhibition may serve as an innovative platform technology for drug delivery to the lower female reproductive tract.

Atomistic details of the associative phosphodiester cleavage in human ribonuclease H.

During translation of the genetic information of DNA into proteins, mRNA is synthesized by RNA polymerase and after the transcription process degraded by RNase H. The endoribonuclease RNase H is a member of the nucleotidyl-transferase (NT) superfamily and is known to hydrolyze the phosphodiester bonds of RNA which is hybridized to DNA. Retroviral RNase H is part of the viral reverse transcriptase enzyme that is indispensable for the proliferation of retroviruses, such as HIV. Inhibitors of this enzyme could therefore provide new drugs against diseases like AIDS. In our study we investigated the molecular mechanism of RNA cleavage by human RNase H using a comprehensive high level DFT/B3LYP QM/MM theoretical method for the calculation of the stationary points and nudged elastic band (NEB) and free energy calculations to identify the transition state structures, the rate limiting step and the reaction barrier. Our calculations reveal that the catalytic mechanism proceeds in two steps and that the nature of the nucleophile is a water molecule. In the first step, the water attack on the scissile phosphorous is followed by a proton transfer from the water to the O2P oxygen and a trigonal bipyramidal pentacoordinated phosphorane is formed. Subsequently, in the second step the proton is shuttled to the O3' oxygen to generate the product state. During the reaction mechanism two Mg(2+) ions support the formation of a stable associated in-line S(N)2-type phosphorane intermediate. Our calculated energy barrier of 19.3 kcal mol(-1) is in excellent agreement with experimental findings (20.5 kcal mol(-1)). These results may contribute to the clarification and understanding of the RNase H reaction mechanism and of further enzymes from the RNase family.

'It should be an ordinary thing'--a qualitative study about young people's experiences of taking the HIV-test and receiving the test result.

Increased HIV-testing has public health benefits, but for youth there is a multitude of barriers against the test. The aim of this study is to explore how young women and men in Sweden experience HIV-testing within primary healthcare.

Sexual practices and dental dam use among women prisoners--a mixed methods study.

Dental dams have been distributed to women prisoners for protection against HIV and other sexually transmissible infections (STIs) in some Canadian and Australian prisons for over a decade. However, we do not know whether they serve any useful public health purpose.

State-of-the-art of non-hormonal methods of contraception: I. Mechanical barrier contraception.

Mechanical barriers, specifically male condoms, command renewed interest and are used today by more people. The worldwide prevalence rate of male condoms was about 6% in 2007 corresponding to 65 million cohabiting couples. The prevalence of female barrier methods, including diaphragms, cervical caps and female condoms has declined to less than 1% of women in North America and in north-west Europe. Even smaller percentages use female barriers elsewhere. First-year life table pregnancy probabilities of mechanical barrier methods range from 4 to 19 per hundred in clinical trials. The male condom is the only proved preventive tool against several sexually transmitted infections (STIs), especially HIV. The effectiveness of the diaphragm and cervical caps in this regard appears limited. Further research is needed to measure the efficacy of female condoms in disease prevention. Sponges are not known to protect against STIs. Because of their ease of use and availability, low short-term costs, relative freedom from side effects, and usefulness in combating STIs, mechanical barrier methods, especially condoms, will continue to be used on a large scale. For our literature search we used personal files, search engines such as Popline, Medline, PubMed and Google, and data bases of WHO, FHI and Cochrane Library.

State-of-the-art of non-hormonal methods of contraception: II. Chemical barrier contraceptives.

Chemical contraceptives mainly known as spermicides are one of the oldest types of contraceptives. The industrial revolution facilitated new developments, and they became a leading and widespread method. However, their use declined in the second half of the 20th century, and came under focus again only with the upsurge of sexually transmitted infections (STIs). The effectiveness of spermicides depends on the users' compliance and pregnancy rates vary widely: from 6/100 woman-year (with perfect use) to 26/100 woman-year (with typical use). Preparations consist of two components: an excipient (foam, cream, jelly, soluble film, suppository or tablet); and a chemical agent with spermicidal properties (acidic compound, microbicidal agent, detergent). The most widely used active agent has been the surface active (detergent) nonoxynol-9 (N-9). Based on their mode of action (surfactant effect of detergents, enzymatic action of microbicides on cell metabolism) spermicides were thought to provide protection against STIs including HIV. Recent studies have, however, shown that detergents may actually increase the risk. Because of this, there is an urgent need for a suitable non-detergent spermicide, and research should focus on developing new compounds to replace N-9 and other agents having similar undesired effects. This paper reviews the latest studies reporting results on these recent developments.

Single-dose escalation and multiple-dose safety, tolerability, and pharmacokinetics of IDX899, a candidate human immunodeficiency virus type 1 nonnucleoside reverse transcriptase inhibitor, in healthy subjects.

IDX899 is a novel nonnucleoside reverse transcriptase inhibitor (NNRTI) with potent in vitro activity against wild-type and NNRTI-resistant strains of human immunodeficiency virus type 1 (HIV-1) and with a high genetic barrier to resistance. Single rising doses of 50 and 100 (given by use of a 50-mg capsule) and 200, 400, 800, and 1,200 mg (given by use of a 200-mg capsule) of IDX899 or matching placebo were administered sequentially to cohorts of healthy male subjects, followed by the administration of multiple doses of 800 mg once daily (QD) or 400 mg twice daily (BID) for 7 days. A single dose of 400 mg was also administered to a cohort of females. IDX899 was administered orally under fasted (50- to 400-mg doses) and then fed (> or = 200-mg doses) conditions. Exposure to IDX899 was dose proportional and comparable in males and females. With a different drug-to-excipient ratio, the 50-mg capsule led to a higher exposure but a shorter mean terminal half-life (t(1/2)) of 6.2 to 6.8 h. The 200-mg capsule resulted in a more sustained exposure with a longer mean t(1/2) of 7.9 to 14.6 h. Food enhanced absorption by approximately twofold, while it delayed the time to the maximum concentration. The mean concentration at 24 h following the administration of a single 200-mg dose under fed conditions exceeded the in vitro protein binding-adjusted 90% inhibitory concentration by fourfold. The levels of plasma exposure were similar between the single dosing and the repeat dosing with 800 mg QD and was approximately twofold higher with 400 mg BID. Mean steady-state trough levels were 0.9 microg/ml (range, 0.2 to 2.5 microg/ml) and 2.1 microg/ml (range, 0.5 to 4.5 microg/ml) for the 800-mg QD and 400-mg BID regimens, respectively. The level of excretion of unchanged drug in urine was negligible. IDX899 was well tolerated; and no serious adverse events, dose-dependent adverse events, or laboratory abnormalities were detected. These favorable safety and pharmacokinetic results support further clinical studies with patients with HIV-1 infection by the use of a QD regimen.

Survey of motivation for use of voluntary counseling and testing services for HIV in a high risk area of Shenyang, China.

HIV voluntary counseling and testing (VCT) is considered an effective prevention method of HIV infection. In order to understand the VCT environment and enhance the effective delivery of VCT services in a country, an accurate assessment of the current status of VCT services is very important.

Darunavir in patients with advanced HIV and multiresistance. The POWER, DUET and BENCHMRK studies.

Darunavir is a new protease inhibitor. This drug is highly active against wild-type and multiresistant HIV strains, binds strongly to the HIV-1 protease, has extremely high affinity for the protease and, when enhanced by subtherapeutic doses of ritonavir, has a favorable resistance profile differing from that of current protease inhibitors (PIs). After determining the optimal dose, phase IIb clinical trials (POWER studies 1 and 2) observed much higher virological and immunological efficacy with darunavir than with the comparator PIs. The results of a phase III clinical trial (POWER 3) provide further support for the safety and efficacy of darunavir, and the three POWER studies demonstrate the high genetic barrier of this drug against mutations conferring resistance to other PIs, although the baseline sensitivity of darunavir and the specific mutations to this PI influence the virological response. Better therapeutic responses have been obtained when there are two or more antiretroviral drugs active against multiresistant HIV strains. The phase III trials (DUET 1 and 2), in which darunavir was administered with the new nonnucleoside reverse transcriptase inhibitor, etravirine, found that if these two drugs were administered in highly treatment-experienced patients, a large percentage showed suppression of plasma viremia and immunological recovery. These data have been supported by the results of the BENCHMARK studies, in which darunavir was included in an optimized regimen in a substantial number of patients. In these trials, when darunavir was administered with the integrase inhibitor, raltegravir, undetectable viral loads both in the raltegravir arm and in the control group were substantially improved with respect to the overall results obtained in the control group.

Modelled in vivo HIV fitness under drug selective pressure and estimated genetic barrier towards resistance are predictive for virological response.

A method has been developed to estimate a fitness landscape experienced by HIV-1 under treatment selective pressure as a function of the genotypic sequence thereby also estimating the genetic barrier to resistance.

Emergence of an NNRTI resistance mutation Y181C in an HIV-infected NNRTI-naive patient.

The purpose of our study was to examine the emergence of the Y181C resistance mutation in an NNRTI-naive subject (index patient) at different time points. Phylogenetic trees in protease (PR) and partial reverse transcriptase (RT) regions were inferred by the maximum likelihood (ML) method. The Y181C mutation was detected for the first time when the patient was receiving d4T + ddI + LPV/r; the previous drug combination was 3TC + AZT + IDV. The particular mutation (Y181C) was not present at any time point during the treatment period with 3TC + AZT + IDV. Moreover, there was no evidence of resistance mutations in RT before the initiation of antiretroviral therapy. Phylogenetic analysis including sequences from the index patient and his spouse sampled at different time points, as well as control sequences belonging to the same HIV-1 subtype, revealed that there is no evidence of coinfection or reinfection with Y181C resistance strains, while the virus for both subjects was classified as subtype CRF14_BG. Overall, our findings suggest that the Y181C resistance mutation may be selected, not only by NNRTIs, but also by d4T. This may be of particular significance in developing countries where treatment with Triomune, a fixed combination of d4T, ddI, and nevirapine, is common. The genetic barrier against resistance of this combination may be lower than previously thought.