Despite efforts at reducing risk behaviour, HIV-positive MSM who clear HCV infection remain at high risk of reinfection. This emphasizes the need for increased sexual education, surveillance and preventive intervention work.

Syphilis, which is caused by the sexually transmitted bacterium Treponema pallidum subsp. pallidum, has an estimated 6.3 million cases worldwide per annum. In the past ten years, the incidence of syphilis has increased by more than 150% in some high-income countries, but the evolution and epidemiology of the epidemic are poorly understood. To characterize the global population structure of T. pallidum, we assembled a geographically and temporally diverse collection of 726 genomes from 626 clinical and 100 laboratory samples collected in 23 countries. We applied phylogenetic analyses and clustering, and found that the global syphilis population comprises just two deeply branching lineages, Nichols and SS14. Both lineages are currently circulating in 12 of the 23 countries sampled. We subdivided T. p.pallidum into 17 distinct sublineages to provide further phylodynamic resolution. Importantly, two Nichols sublineages have expanded clonally across 9 countries contemporaneously with SS14. Moreover, pairwise genome analyses revealed examples of isolates collected within the last 20 years from 14 different countries that had genetically identical core genomes, which might indicate frequent exchange through international transmission. It is striking that most samples collected before 1983 are phylogenetically distinct from more recently isolated sublineages. Using Bayesian temporal analysis, we detected a population bottleneck occurring during the late 1990s, followed by rapid population expansion in the 2000s that was driven by the dominant T. pallidum sublineages circulating today. This expansion may be linked to changing epidemiology, immune evasion or fitness under antimicrobial selection pressure, since many of the contemporary syphilis lineages we have characterized are resistant to macrolides.

Anandamide is a ligand of the endocannabinoid system. Animals show a depletion following repeated Δ(9)-tetrahydrocannabinol (THC) administration but the effect of cannabis use on central nervous system levels of endocannabinoids has not been previously examined in humans. Cerebrospinal fluid (CSF) levels of the endocannabinoids anandamide, 2-arachidonoylglycerol (2-AG) and related lipids were tested in 33 volunteers (20 cannabis users). Lower levels of CSF anandamide and higher levels of 2-AG in serum were observed in frequent compared with infrequent cannabis users. Levels of CSF anandamide were negatively correlated with persisting psychotic symptoms when drug-free. Higher levels of anandamide are associated with a lower risk of psychotic symptoms following cannabis use.

No abstract

Loss of Th22 cells and disruption in the balance of Th22 and Treg cells may contribute toward systemic immune activation and mucosal immune deficiency during HIV-1 infection.

High rates of SVR (62%) were obtained in HIV-coinfected patients with acute HCV infection undergoing early anti-HCV treatment using pegylated interferon alone or in combination with ribavirin. Treatment response at weeks 4 and 12 might be of help to further guide treatment duration. Urgent prospective studies are needed to further determine the optimal treatment regimen and the duration of therapy.

Fibrosis progression after acute hepatitis C virus (HCV) infection in human immunodeficiency virus (HIV)-infected patients with follow-up >9 months became similar to reported rates from studies in chronic HIV/HCV coinfection, as measured with transient elastometry. The duration of follow-up and serum alanine transaminase correlated with liver stiffness, and short follow-up resulted in high fibrosis progression rates.

Large-scale longitudinal clinical studies are needed to confirm the importance of microbial translocation in promotion of hepatic fibrosis. If microbial translocation is a significant contributory factor to hepatic fibrosis, targeted interventions against microbial products may improve clinical outcomes.