Microbicides and HIV: help or hindrance?

We present a simple mathematical model for assessing the effects of introducing a microbicide as an HIV infection protective method. As very little is known about the in vivo efficacy of microbicides, we ran sample scenarios for microbicides of various efficacies. We found that, in general, if existing condom usage in a community is low, introducing a microbicide will most likely have a positive impact on HIV incidence as abandonment of condom use in favor of microbicides will not play a significant role. If condom use in a community is high, though, attrition of condom users could play a role large enough to overwhelm any added risk reduction afforded new microbicide users. Our model illustrates the importance of knowing key behavioral parameters, such as the proportion of the population that uses condoms, before microbicides can be safely introduced. These parameters include the proportion of condom users likely to maintain condom use and the proportion of condom nonusers likely to adopt microbicides, as well as the efficacy of the candidate microbicide.     

HLA-G and mother–child perinatal HIV transmission

Transplacental passage is a well-known phenomenon in HIV infection and immune responses at the maternal-fetal interface play a critical role in perinatal mother-to-child HIV transmission (MCHT). The high expression of HLA-G at the maternal-fetal interface and its role in mediating immune tolerance suggest that it could play an important role in MCHT. We investigated the role of HLA-G polymorphism in perinatal HIV transmission in 348 ART naïve mother–child pairs enrolled in a mother–child HIV transmission cohort, established in Nairobi, Kenya in 1986.     

Women and HIV: when to test?

The devastating effects of HIV infection in women can be altered dramatically with new therapies. Certain clinical syndromes, including oral thrush, diffuse lymphadenopathy, wasting, unexplained fevers, or oral hairy leukoplakia, clearly indicate a need for HIV testing. This article reviews other clinical syndromes, both gender-specific and non-gender-specific, that may prompt the practitioner to consider HIV testing.     

Human defensins: prophylaxis and therapy against HIV?

Human defensins are endogenous antimicrobial peptides with prophylactic and therapeutic potential against HIV. The ability of defensins to bind the HIV envelope could be exploited to design topic agents that block viral entry into exposed mucosa. Additionally, their capacity to inhibit viral replication, complement system activation, dendritic and memory T cells chemoattraction, together with peptide engineering could bring about new and better antiretroviral drugs. Clinical trials could be demonstrated the efficacy of defensins against HIV in clinical practice.     

Mutants from V79 fibroblasts exhibiting hypersensitivity to aphidicolin and 3′-azido-3′-deoxythymidine

One variant, aph^hs-3 was previously isolated based on a hypersensitivity to nontoxic concentrations of aphidicolin, a specific inhibitor of DNA polymerases-alpha and delta. This variant was found to be more sensitive to temperatures above 35°C and to 10 µM of 3-azido-3-deoxythymidine (zidovudine, azidothymidine, or AZT) than the parental 743x cells. DNA polymerase activities in the cell extract or in the partially purified fraction by DEAE-cellulose (DE52) anion exchange column from aph^hs-3 were active at 40°C. No significant differences in deoxynucleoside triphosphate pools were observed at 34°C for both the parental 743x and aph^hs-3 cells. Revertants were isolated at 39°C: six revertants (aph^hs-3-tr1 through aph^hs-3-tr6) were obtained without aphidicolin; one revertant aph^hs-3-tar (the tar clone) was selected in aphidicolin (0.12 µM). The hypersensitivity to aphidicolin (Aph^hs) and AZT (AZT^hs) was cosegregated in the revertant aph^hs-3-tr5 (the tr5 clone), while the tar clone was not AZT^hs. There was a similar increase in the specific activity of³H-labeled DNA in all cell lines after additions of [³H]AZT or [³H]thymidine. Additions of purine or pyrimidine arabinosides (araT, araC, and araA) to all cell lines resulted in a similar cytotoxicity, suggesting the anabolism of dTTP was not defective in the tr5 clone. The spontaneous mutation rate at the hypoxanthine-guanine phosphoryltransferase locus using replating techniques and 6-thioguanine resistance selection was 5×10^–7, 2.2×10^–6, or 1.3×10^–6 per generation for the tr5, 743x, or tar cell lines, respectively. Most importantly, DNA polymerase activities in the cell extract of the revertant tr5 clone were inhibited by 0.5 µM AZTTP. In contrast, no inhibition was observed in those of the parental 743x and revertant tar cells. The cosegregation of both Aph^hs and AZT^hs in the tr5 revertant suggests that these two phenotypes may be a result of the same mutational event.     

Hospital pharmacists’ knowledge about and attitude toward HIV/AIDS and patients living with HIV/AIDS in Kedah,Malaysia

Introduction

The current study aims to explore the knowledge, attitude, and perception of hospital pharmacists towards HIV/AIDS and patients living with HIV/AIDS (PLWHA) in the state of Kedah, Malaysia.

Material and methods

This was a cross-sectional study conducted among the hospital pharmacists in three government hospitals in Kedah, using a self-administered 43-item questionnaire. Data analysis was done using non-parametric and multinomial regression.

Results

A total of 75 respondents participated in this study, resulting in a response rate of 60.8%. The majority were found to be well aware of the causes of HIV/AIDS. However, about 34 (45.3%) believed erroneously that HIV/AIDS cannot be transmitted through tattooing or body piercing. Nearly 25 (33.3%) of the respondents believed that preventing the use of intravenous drugs may not be effective to prevent HIV/AIDS and endorsed social isolation as a measure to prevent HIV/AIDS. The majority (66.6%) had negative attitudes and about 20% held extremely negative attitudes. Findings from regression modelling revealed that hospital (–2 log likelihood = 215.182, χ² = 18.060, Df = 8, p = 0.021) and gender (–2 log likelihood = 213.643, χ² = 16.521, Df = 8, p = 0.035) were more likely to affect the attitudes of respondents.

Conclusions

Overall, more than one third of the respondents were found to have negative attitudes towards PLWHA. Gender, job experience, and hospitals with more HIV/AIDS patient visits were the main factors affecting attitudes.     

TB and HIV: deadly liaison or manageable threat?

Researchers create a dynamic model that could resolve conflicting findings on the effects of HIV infection on drug-resistant tuberculosis.     

HIV immunosupression and malaria: is there a correlation?

The human immunodeficiency virus (HIV) epidemic has resulted in an increase in the prevalence of many opportunistic infections and has caused re-emergence of certain diseases in the developing world. In tropical countries, immunosupression due to HIV infection has resulted in changes in the clinical presentation of endemic infections. Although the immune deficiency caused by HIV infection should presumably lead to an increased frequency of clinical malaria in areas with endemic malarial infection, like India, evidence of the association between HIV and malaria in India is scanty, with only a few studies showing a positive correlation. We hereby report a case of concurrent infection with Plasmodium falciparum malaria and human immunodeficiency virus type 1 (HIV-1) in a young male patient.     

The viral RNA 3′- and 5′-end structure and mRNA transcription of infectious salmon anaemia virus resemble those of influenza viruses

The nucleotide sequences of the termini of two of the genomic segments of the negative strand RNA virus infectious salmon anaemia virus (ISAV) were determined. The sequence of the terminal 9 nucleotides at both ends of the viral RNAs was identical, and showed distinctive sequence homology with the conserved terminal sequences found in the orthomyxoviruses. For both ISAV genomic segments a computer-based secondary structure modelling indicated that the terminal 21-24 nucleotides were able to form self-complementary panhandle structures. Comparison with ISAV-derived mRNA sequences showed that ISAV mRNAs have heterogeneous 5'-ends, and are polyadenylated from a signal sequence 13-14 nucleotides downstream of the 5'-end terminus of the vRNA. Furthermore, the in vitro replication of ISAV was hindered by the RNA polymerase II inhibitor alpha-amanitin. These findings indicate that the mechanisms for replication of ISAV are similar to those of the orthomyxoviruses, and add to the previously reported structural similarities between ISAV and the orthomyxoviruses.