Expression of the fragile site Xq27 in fibroblasts. I. Detection of Fra(X)(q27) in fibroblast clones from males with X-linked mental retardation

Summary Twelve fibroblast clones from two males with X-linked mental retardation expressed the fragile site Xq27 in 3%–38% of metaphases analyzed. The number of in vitro doublings during the cloning procedure had no evident influence on the induction of fragile X expression. The variability of fragile X expression seems to depend on cell properties acquired during culture rather than on properties originally inherent in the cells.     

In vitro effects of photobiomodulation therapy on 50B11 sensory neurons: evaluation of cell metabolism,oxidative stress,mitochondrial membrane potential (MMP), and capsaicin-induced calcium flow

The analgesic properties of photobiomodulation therapy (PBMT) have been raising increasing interest in the clinical community due to the positive effects observed on patients, nevertheless the mechanistic basis of its action on peripheral sensory neurons remains still elusive. In this study, the effect of near-infrared (NIR) PBMT at 800 and 970 nm of wavelength was investigated on the 50B11 immortalized nociceptive sensory neuronal cell line by evaluating capsaicin-induced calcium flow and different markers correlated to mitochondria, that is, ATP, reactive oxygen species (ROS), and mitochondrial membrane potential (MMP). Calcium peak stimulated by capsaicin, the ligand of TRPV1 channel, was decreased in neurons pre-irradiated with the combination of the two wavelengths. Furthermore, delivering the 800 and 970 nm separately an increment of ATP, as well as MMP hyperpolarization were detected; notably, the 800 nm wavelength also increased ROS and O₂⁻ levels. Our findings, obtained on an in vitro model of nociception, show the positive effect of PBMT on two potential photo-targets of NIR light, namely the TRPV1 channel and the mitochondria.     

Inhibition of mouse lymphocyte proliferative response by glycosphingolipids from Leishmania (L.) amazonensis.

The effect of a purified preparation of glycosphingolipids (GSLs) extracted from Leishmania (L.) amazonensis amastigotes on murine lymphocytes was investigated. GSLs inhibited both concanavalin A (Con A)- or lipopolysaccharide-induced [3H]thymidine uptake by normal and immunized BALB/c mouse lymph node cells. The effect of total GSLs was dose dependent. Total GSLs also suppressed the two-way mixed lymphocyte reaction of BALB/c x C57BL/6 cells and the antigen-specific response of immunized mouse cells. Six pure bands as well as a pool containing a mixture of GSLs with five to seven sugar residues separated by a combination of HPLC and preparative HPTLC were tested and shown to be inhibitors of Con A stimulation. These results suggest that parasite glycosphingolipids may play an immunologically relevant role in leishmaniasis.