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Critical thinking is considered one of the key competencies of university students and its importance increases with the effort to develop students' creativity, independence as well as scientific thinking. For this skill, it is important to have confidence in one's ability to solve problems, find relevant answers or to formulate defensible conclusions. The aim of the paper was to determine whether academic self-efficacy acted as a precondition for critical thinking in university students. A total of 451 university students were involved in this study. The data were obtained by The Critical Thinking Disposition Inventory and the Academic Self-Efficacy Scale. The results showed that academic self-efficacy predicted all the three dimensions of critical thinking, albeit with a small amount of explained variance ranging from 8.1 to 12.2%. Although the main factor moderating each dimension of critical thinking is the effect of academic self-efficacy, a gender interaction effect was also found, which was more evident for males than females.

Background: Trichofolliculomas and trichoepitheliomas are benign skin neoplasms originating from hair follicle cells. They result from defects in the signaling pathways that regulate hair follicle morphogenesis and regeneration. Thus they seem to be an excellent model of these processes. It is known that the E-cadherin/beta-catenin system of adhesion molecules plays a crucial role in the maintenance of tissue architecture., Aim: The aim of the present study was to investigate their involvement in benign hair follicle tumor development., Methods: Semiquantitative intensity of expression were examined in formalin-fixed and paraffin-embedded tissue sections of 53 trichoepitheliomas, 15 trichofolliculomas and 19 normal skin samples by indirect immunohistochemistry., Results: The intensity of E-cadherin/beta-catenin expression in tumor cells did not differ from controls. However, normal hair follicles cells exhibited membranous E-cadherin/beta-catenin expression, whereas both types of tumors, particularly trichoepitheliomas, showed E-cadherin/beta-catenin expression with a predominantly cytoplasmic localization., Conclusions: We suggest that this dystopic distribution of the E-cadherin/beta-catenin complex in hair follicle tumor cells may be a marker of cell-cell adhesion disruption which may contribute to the tumor formation.

Background: Aberrant expression of either growth factors or growth factor-receptors by stromal cells can be an important factor promoting the growth of solid tumours. It may also affect differentiation of malignant cells and support tumour spread. The aim of the present study was to investigate the hypothesis that basic-fibroblast growth factor (bFGF) and platelet-derived growth factor (PDEGF) may be involved in tumour-stromal microenvironment interactions in primary malignant melanomas., Materials and Methods: PDEGF and bFGF expression in malignant cells and surrounding stromal elements was assessed using indirect immunohistochemistry., Results: It was confirmed that PDEGF can be involved in the reciprocal interactions between tumour cells and stroma, including aberrant angiogenesis. Interestingly, bFGF was present both in malignant melanoma lesions and benign nevi accompanied by different intracellular localisation of the protein, suggesting its implication in regulation of nevus cell proliferation and maturation., Conclusion: The present results suggest that bFGF and PDEGF participate in malignant melanoma progression.