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Human Wharton’s jelly mesenchymal stem cells (WJ-MSCs) exhibit CD29, CD79 and CD105 markers, characteristic for mesenchymal cell lines. Under the influence of the appropriate factors, WJ-MSCs can be dedifferentiated to osteoblasts, chondrocytes, adipocytes, myocytes, cardiomyocytes, glial cells and dopaminergic neurons. Wharton’s jelly (WJ) is one of the potential sources of mesenchymal stem cells (MSCs) - obtaining these cells does not raise moral or ethical objections, because the umbilical cord (UC) is a regular waste material. The expression of the OCT-4 and Nanog proteins, which are characteristic for WJ-MSCs may indicate that these cells have retained some embryonic character. The collected data suggests that WJMSCs show increased division and telomerase activity compared to bone marrow MSCs (BM-MSCs). The published results showed no human leucocyte antigen (HLA) class II expression, with the possibility of HLA class I modification by WJ-MSCs, allowing for the transplantation of these cells both within the same and other species - which allows the use of human cells in animal models. The results of selected studies indicate that WJ-MSCs can be an essential element of regenerative medicine of the 21st century.

Today adolescents are highly engaged online. Contrary to common concern, not all highly engaged adolescents develop maladaptive patterns of internet use. The present qualitative study explored the experiences, patterns and impact of use of 124 adolescents (Mage=16.0) reporting signs of internet addictive behaviors. The focus was to discern adaptive and maladaptive use patterns, which promote or interfere with adolescents' development, respectively. Semi-structured individual interviews were conducted in seven European countries (Greece, Spain, Poland, Germany, Romania, Netherlands and Iceland) and qualitatively analyzed using grounded theory. Considerable variability emerged in the way adolescents satisfied their personal needs online and offline, in the experienced impact from high online engagement and functional value ascribed to the internet, and in the self-regulatory processes underlying use. Variability in these discriminating processes was linked to adaptive or maladaptive adolescent internet use patterns. The emerged processes can provide direction for designing prevention and intervention programs promoting adaptive use. © 2014 The Foundation for Professionals in Services for Adolescents.

Cyberbullying victimization is an important adolescent health issue. The cross-national study aimed to investigate the prevalence of cyber victimization and associated internalizing, externalizing and academic problems among adolescents in six European countries. A cross-sectional school-based study of 14-17 year-old adolescents (N = 10,930; F/M: 5719/5211; mean age 15.8 ± 0.7 years) was conducted in Spain, Poland, the Netherlands, Romania, Iceland and Greece. In total, 21.4% of adolescents reported cyber victimization in the past 12 months. Reports were more frequent among girls than boys (23.9% vs. 18.5%), and among the older adolescents compared to the younger ones (24.2% vs. 19.7%). The prevalence was highest in Romania and Greece (37.3% and 26.8%) and lowest in Spain and Iceland (13.3% and 13.5%). Multiple logistic regression analysis indicated that cyber victimization was more frequent among adolescents using the internet and social networking sites for two or more hours daily. Multiple linear regression analysis showed that externalizing, internalizing and academic problems were associated with cyber victimization. Overall, cyber victimization was found to be a problem of substantial extent, concerning more than one in five of the studied European adolescents. Action against cyber victimization is crucial while policy planning should be aimed at the prevention of the phenomenon. © 2015 Elsevier Ltd.

In order to study the most abundant GABAA receptor subtypes expressed in cholinergic, dopaminergic, noradrenergic and serotonergic neurons (i.e., in neurons of the so-called "global" projection systems), we employed double-immunocytochemical techniques combining the labeling of GABAA receptor alpha1, alpha2 and alpha3 subunit with markers for these cells. Cholinergic neurons in the striatum, habenula, and pedunculo-pontine nucleus were immunonegative for the alpha1 subunit, and most were also alpha2-immunonegative. However, cholinergic neurons in the striatum, septum and pedunculo-pontine nucleus were alpha3 immunopositive. Dopaminergic neurons in the substantia nigra pars compacta were highly immunopositive for the alpha3, and noradrenergic neurons in the locus coeruleus were immunoreactive for the alpha3 and the alpha2-subunit; although neurons of these areas were negative for alpha1. Similarly, serotonergic neurons in raphe also showed a high level of labeling of alpha3, while there was a lack of immunoreactivity for the alpha1-subunit, and only some individual neurons were positive for the alpha2 subunit. As the presence of different alpha-subunits confers specific physiological and pharmacological properties to GABAA receptors, the abundance of receptors containing the alpha3 subunit (and the scarcity of receptor subtypes including the other alpha-subunits studied) may have important implications for the GABAergic regulation of brain "global" or "diffuse" projection systems.