Molecular epidemiology of Enterocytozoon bieneusi and Encephalitozoon sp., among immunocompromised and immunocompetent subjects in Iran

We announce the release of an advanced version of the Molecular Evolutionary Genetics Analysis (MEGA) software, which currently contains facilities for building sequence alignments, inferring phylogenetic histories, and conducting molecular evolutionary analysis. In version 6.0, MEGA now enables the inference of timetrees, as it implements the RelTime method for estimating divergence times for all branching points in a phylogeny. A new Timetree Wizard in MEGA6 facilitates this timetree inference by providing a graphical user interface (GUI) to specify the phylogeny and calibration constraints step-by-step. This version also contains enhanced algorithms to search for the optimal trees under evolutionary criteria and implements a more advanced memory management that can double the size of sequence data sets to which MEGA can be applied. Both GUI and command-line versions of MEGA6 can be downloaded from www.megasoftware.net free of charge.

RA is known to be associated with an increased risk of serious infection. Even more than 50 years ago, observational studies showed a greater than 2-fold increased risk of serious infection in RA. This was reinforced by various subsequent cohort studies. The elevated susceptibility of patients with RA can be explained by the pathobiology of the disease itself, the impact of chronic comorbid conditions, as well as sequelae of immunosuppressive treatment. It has been suggested that premature ageing of the immune system in RA contributes to weakened protection against infectious organisms. In addition, chronic comorbid conditions such as diabetes or chronic lung or kidney disease, disease-related functional disability, as well as lifestyle factors such as smoking, increase the risk in individual patients. For a long time glucocorticoids (GCs) have been used as potent immunosuppressive drugs in RA. There is evidence that they increase the risk of serious infections up to 4-fold in a dose-dependent manner. TNF-α inhibitors increase the serious infection risk up to 2-fold. They have, however, the potential to outweigh their risk when higher GC doses can be tapered down. If patients need higher dosages of GCs in addition to treatment with biologic agents, their risk of infection is substantial. This combination should be used carefully and, if possible, avoided in patients with additional risk factors such as older age or comorbid conditions.