HIV infection is a major problem in Indonesia. The number of people living with HIV has been increasing from year to year, especially among injecting drug users (IDUs). Since there were only limited data about molecular epidemiology profiles of HIV/AIDS in Indonesia, a cross-sectional study involving 208 HIV-1-seropositive individuals was conducted in 2007 in Jakarta. The majority of participants were 16-30 years of age (64.9%) and 74.5% were male. The most frequent risk factor was injecting drug use (IDU) (45.7%) followed by heterosexual transmission (34.1%). Phylogenetic analysis of gag (p17 and p6) and env C2V3 regions showed 200 (96.2%) of 208 DNA samples were CRF01_AE and only 3 (1.4%) were subtype B. Five samples (2.4%) indicated discordant subtypes between the three aforementioned regions: three of them showed unique CRF01_AE/B recombination patterns in 2.3-kbp nucleotide sequences (from p17 to part of RT), including one sample showing similarity to CRF33_01B, reported previously in Malaysia. This study shows the current predominant subtype is CRF01_AE in every risk group, with a decreasing number of pure subtype B, and the first identification of CRF01_AE/B recombinant forms among HIV-1-seropositive Indonesians.
White matter (WM) fiber bundles change dynamically with age. These changes could be driven by alterations in axonal diameter, axonal density, and myelin content. In this study, we applied a novel fixel-based analysis (FBA) framework to examine these changes throughout the adult lifespan. Using diffusion-weighted images from a cohort of 293 healthy volunteers (89 males/204 females) from ages 21 to 86 years old, we performed FBA to analyze age-related changes in microscopic fiber density (FD) and macroscopic fiber morphology (fiber cross section [FC]). Our results showed significant and widespread age-related alterations in FD and FC across the whole brain. Interestingly, some fiber bundles such as the anterior thalamic radiation, corpus callosum, and superior longitudinal fasciculus only showed significant negative relationship with age in FD values, but not in FC. On the other hand, some segments of the cerebello-thalamo-cortical pathway only showed significant negative relationship with age in FC, but not in FD. Analysis at the tract-level also showed that major fiber tract groups predominantly distributed in the frontal lobe (cingulum, forceps minor) exhibited greater vulnerability to the aging process than the others. Differences in FC and the combined measure of FD and cross section values observed between sexes were mostly driven by differences in brain sizes although male participants tended to exhibit steeper negative linear relationship with age in FD as compared to female participants. Overall, these findings provide further insights into the structural changes the brain's WM undergoes due to the aging process.