[Neuro-AIDS in the cART era]

The default mode network is affected in the early stage of simian immunodeficiency virus infection: a longitudinal study

Acquired immune deficiency syndrome infection can lead to cognitive dysfunction represented by changes in the default mode network. Most recent studies have been cross-sectional and thus have not revealed dynamic changes in the default mode network following acquired immune deficiency syndrome infection and antiretroviral therapy. Specifically, when brain imaging data at only one time point are analyzed, determining the duration at which the default mode network is the most effective following antiretroviral therapy after the occurrence of acquired immune deficiency syndrome. However, because infection times and other factors are often uncertain, longitudinal studies cannot be conducted directly in the clinic. Therefore, in this study, we performed a longitudinal study on the dynamic changes in the default mode network over time in a rhesus monkey model of simian immunodeficiency virus infection. We found marked changes in default mode network connectivity in 11 pairs of regions of interest at baseline and 10 days and 4 weeks after virus inoculation. Significant interactions between treatment and time were observed in the default mode network connectivity of regions of interest pairs area 31/V6.R and area 8/frontal eye field (FEF). L, area 8/FEF.L and caudal temporal parietal occipital area (TPOC).R, and area 31/V6.R and TPOC.L. ART administered 4 weeks after infection not only interrupted the progress of simian immunodeficiency virus infection but also preserved brain function to a large extent. These findings suggest that the default mode network is affected in the early stage of simian immunodeficiency virus infection and that it may serve as a potential biomarker for early changes in brain function and an objective indicator for making early clinical intervention decisions.

[The Competence Network for HIV/AIDS. Data, Samples, Facts]

BACKGROUND

With funding for the Competence Networks in Medicine from the Federal Ministry of Education and Research, the Competence Network for HIV/AIDS (KompNet HIV/AIDS) was established as an interdisciplinary research association. Essential working groups were incorporated all over Germany, which are active in clinical and basic HIV/AIDS research.

OBJECTIVES

After successful establishment, providing research infrastructure for national and international cooperation in the field of HIV/AIDS was the focus of the network. By bringing together research activities, preconditions are created for improving HIV infection treatment and increasing life expectancy of HIV-infected patients.

MATERIALS AND METHODS

The members of KompNet HIV/AIDS are HIV experts from university clinics, HIV physicians, patient representatives, as well as national reference centers. As a scientific research basis, the network established an HIV patient cohort. Clinical and sociodemographic data of HIV patients were documented biannually and complemented by serum and DNA-samples collected twice per year. Furthermore, a child cohort was set up.

RESULTS AND CONCLUSION

Within the KompNet HIV/AIDS, a research infrastructure for HIV was established for internal, external as well international scientists. Within the HIV cohort a total of 16,500 patients are documented. The associated biobank comprises ~ 56,000 serum samples and ~ 16,000 DNA samples. The child cohort consists of 647 HIV-exposed and 230 infected children. The KompNet HIV/AIDS cohorts became an important partner in several international collaborations. Nevertheless, the maintenance of such infrastructures without public funding is a challenge.

The dopamine-related polymorphisms BDNF, COMT, DRD2, DRD3, and DRD4 are not linked with changes in CSF dopamine levels and frequency of HIV infection

We showed previously that higher levels in CSF dopamine in HIV patients are associated with the presence of the dopamine transporter (DAT) 10/10-repeat allele which was also detected more frequently in HIV-infected individuals compared to uninfected subjects. In the current study, we investigated further whether other genetic dopamine (DA)-related polymorphisms may be related with changes in CSF DA levels and frequency of HIV infection in HIV-infected subjects. Specifically, we studied genetic polymorphisms of brain-derived neurotrophic factor, catechol-O-methyltransferase, and dopamine receptors DRD2, DRD3, and DRD4 genetic polymorphisms in uninfected and HIV-infected people in two different ethnical groups, a German cohort (Caucasian, 72 individuals with HIV infection and 22 individuals without HIV infection) and a South African cohort (Xhosan, 54 individuals with HIV infection and 19 individuals without HIV infection). We correlated the polymorphisms with CSF DA levels, HIV dementia score, CD4⁺ T cell counts, and HIV viral load. None of the investigated DA-related polymorphisms was associated with altered CSF DA levels, CD4⁺ T cell count, viral load, and HIV dementia score. The respective allele frequencies were equally distributed between HIV-infected patients and controls. Our findings do not show any influence of the studied genetic polymorphisms on CSF DA levels and HIV infection. This is in contrast to what we found previously for the DAT 3'UTR VNTR and highlights the specific role of the DAT VNTR in HIV infection and disease.

The reliability of the modified lower extremity functional scale among adults living with HIV on antiretroviral therapy, in Rwanda, Africa

Peripheral neuropathy (PN) is common among people living with HIV (PLHIV) on antiretroviral therapy (ART), and affects their daily functional ability and quality of life. Lower extremity functional ability, which is most commonly compromised in patients with PN, has not been clearly evaluated in an African setting, with regard to functional limitations. The lower extremity functional scale (LEFS) was originally developed and validated among elderly people in the USA, where the environment and activities of daily life are very different from those in Rwanda. The purpose of this study was to adapt and establish the reliability of LEFS, among adults living with HIV on ART, in a Rwandan environment. The study translated LEFS from English to Kinyarwanda, the local language spoken in Rwanda, the LEFS was then modified accordingly, and tested for test-retest reliability among 50 adult PLHIV on ART. An average Spearman rank order correlation coefficient, ρ ≥ 0.7, was considered optimal for reliability. Prior to the modification of the LEFS and in the initial testing of the translated LEFS, none of the activities was strongly correlated (ρ ≥ 0.8); most of the activities (90%, 18/20) were moderately correlated (ρ ≥ 0.5) and 10% (2/20) were weakly correlated (ρ ≤ 0.5). The ρ of most of the functional activities improved after modification by an expert group to ρ ≥ 0.7, establishing reliability and validity of LEFS among PLHIV on ART with lower extremity functional limitations, in this environment. In conclusion, this study demonstrated the importance of modifying and establishing test - retest reliability of tools derived from developed world contexts to local conditions in developing countries, such as in Rwanda. The modified LEFS in this study can be used in Rwanda by clinicians, specifically at ART clinics to screen and identify people with functional limitations at an early stage of the limitations, for treatment, rehabilitation and/or referral to appropriate health care services.