Optimizing culture conditions that reduce genomic instability in human pluripotent stem cells (hPSCs) is an unmet challenge in the field. Results from our lab and numerous research groups demonstrate that hPSCs are prone to genomic aberrations and single-cell passaging increases the rate of genomic alterations. However, single-cell based passaging maintains advantages for scale-up and standardizing differentiation protocols. In this study, we investigated the problem of genomic instability in hPSC cultures with the goal towards identifying and characterizing candidate genes that could contribute to generation and survival of abnormal hPSCs. Based on microarray analysis, we identify ARHGDIA, located on 17q25, as a candidate gene conferring selective advantage to trisomy 17 hPSCs. Using lentiviral approaches to overexpress ARHGDIA in hPSCs, [hPSC (Arg)], we functionally validate that in enzymatically passaged co-cultures, hPSC (Arg) lines exhibit competitive advantage against wild type hPSCs, [hPSC (WT)]. Additionally, hPSC (Arg) lines exhibit increased single-cell survival at low density plating. In co-cultures with hPSC (WT), ROCKi exposure attenuated the competitive advantage of hPSC (Arg) subpopulations. For the first time, this work demonstrates that increased expression of a gene on 17q25 confers selective advantage to hPSCs. In parallel studies, using medium devoid of bFGF containing LIF plus two inhibitors, MEK inhibitor (PD0325901) and p38 inhibitor (SB203580), we demonstrate that hPSCs are LIF responsive and can be stably maintained in naive pluripotent culture conditions. Based on their clonal viability, we propose that naive hPSCs are a more genetically stable population than primed hPSCs, when passaged as single- cells. These studies will aid the long-term goal of hPSC scale-up while promoting stable propagation of genomically normal hPSCs.

The thesis deals with the development of identity in adolescence, especially the differentiation between the disharmonic and harmonious development. The main focus was the translation and cultural adaptation as well as the testing of the foreign self-report questionnaire AIDA (Assessment of Identity Development in Adolescence), which was accompanied by another research method - an open question asking the respondents for self- description. The AIDA questionnaire is aimed at detecting and recognition of the dangers of identity development in adolescence. One of the chief goals of the thesis is also checking the psychometric properties of these methods and their comparison. Among other determinants, age groups (11-18 years) and sex, or, gender of the respondents were taken into account. In 2012 Goth, Foelsch, Schlüter-Müller and Schmeck introduced the reliable and valid self-report questionnaire AIDA (Assessment of Identity Development in Adolescence), to assess pathology-related identity development in healthy and disturbed adolescents. The culture-adequate formulations for every original item were developed in a series of beta-tests, pilot tests, and a main testing to establish the Czech version of AIDA. Specific cultural idioms and culture-specific aspects were considered. During the main testing,...

No description available.