Human skeletal muscle-derived stem/progenitor cells modified with connexin-43 prevent arrhythmia in rat post-infarction hearts and influence gene expression in the myocardium.

Stem cell therapy in combination with genetic modification (e.g., transfection with the coding sequence for the connexion 43 gene, GJA1) may solve the problems associated with the occurrence of additional (secondary) stimulation in the post-infarcted heart (arrhythmia). Human skeletal muscle-derived stem/progenitor cells (SkMDS/PCs) were transfected with the pCiNeo-GJA1 plasmid at an efficiency of approximately 96%. Gene overexpression was assessed using qPCR, and subsequent analysis revealed that GJA1 expression increased more than 40-fold in SkMDS/PCs transfected with the appropriate coding sequence (SkMDS/PCsCX43) compared to that of the 'native' SkMDS/PCs control (SkMDS/PCsWT). Enhanced (4-fold) protein expression of connexin-43 was also confirmed by Western immunoblotting. Furthermore, using the arrhythmic score, we demonstrated the positive effects of SkMDS/PCsCX43 cell intervention in reducing additional secondary stimulations in rat post-infarcted hearts compared with that of wild-type cell delivery. Selected gene responses (Kcnq1, Cacna1c, Ncx1, Serca2a, and Tgfb1) showed significantly altered expression profiles in the rat myocardium upon intervention with SkMDS/PCsCX43. The genetic modification of human skeletal muscle-derived stem/progenitor cells with connexin-43 prevented the pro-arrhythmic effects of myogenic implanted stem cells on the host myocardium and positively influenced myocardial gene expression profiles in respect to myocardium conductivity.

Can preschool-aged children swallow several minitablets at a time? Results from a clinical pilot study.

Minitablets are a novel, multi-compartment solid drug formulation, particularly intended for children between 1 and 6 years of age. Available literature shows that even infants are capable of swallowing a single minitablet. In this study, we have explored the level of acceptance of minitablets administered in units of 5 or 10. A group of thirty two 2-year-old children (2-years) and twenty eight 3-year-old children (3-years) have been enrolled in the study. Each child was asked to swallow placebo minitablets (2mm or 3mm) suspended in a fruity jelly on a spoon. The swallowing of minitablets (with or without chewing) was registered for 75% of 2-year-olds and for 93% of 3-year-olds. Moreover, most of the children (57% of all participants) were fully capable of swallowing all units without chewing (2-years: 50%; 3-years: 64%). However, no statistically significant differences in the swallowing ability were observed in gender and age groups. None of the children choked. Neither the number, nor the diameter of the administered minitablets have significantly influenced the ability to swallow units. The results show that minitablets administered in several units mixed with jelly food are safe and could be accepted by a pediatric population.