Cavernomas of the human brainstem: 3-dimensional reconstruction from histological slides using computerized techniques.

Cerebral cavernous malformations (CCMs) are described as vascular lesions consisting of endothelial-lined dilated vessels embedded in a connective tissue sheath without intervening parenchyma between them. Their anatomical connections with the normal blood vessels are still enigmatic and the fine three-dimensional (3-D) organization of these vascular lesions remains to be established. Two stacks of serial histological slices, obtained from two brainstem CCM lesions (from the necropsy of a CCM2 male patient), were stained using Masson's trichrome method and then digitized.

Structural layers of ex vivo rat hippocampus at 7T MRI.

Magnetic resonance imaging (MRI) applied to the hippocampus is challenging in studies of the neurophysiology of memory and the physiopathology of numerous diseases such as epilepsy, Alzheimer's disease, ischemia, and depression. The hippocampus is a well-delineated cerebral structure with a multi-layered organization. Imaging of hippocampus layers is limited to a few studies and requires high magnetic field and gradient strength.

Resistance to macrolides in clinical isolates of Streptococcus pyogenes due to ribosomal mutations.

Objective: Two clinical strains of Streptococcus pyogenes, 237 and 544, one isolated in Slovakia and the other in Croatia, that were resistant to azithromycin (MIC 8 and 2 mg/L, respectively) but susceptible to erythromycin (MIC 0.5 and 0.12 mg/L, respectively) did not contain any gene known to confer macrolide resistance by ribosomal modification (erm gene) or efflux [mef(A) and msr(A) genes].

Diversity of ribosomal mutations conferring resistance to macrolides, clindamycin, streptogramin, and telithromycin in Streptococcus pneumoniae.

Mechanisms of resistance were studied in 22 macrolide-resistant mutants selected in vitro from 5 parental strains of macrolide-susceptible Streptococcus pneumoniae by serial passage in various macrolides (T. A. Davies, B.