In both prism and virtual reality experiments, it has been observed that visual displacement leads to an adaptation of the sensorimotor system. A characteristic of adaptation is the occurrence of the aftereffect, which is the spatial deviation of the movements in the direction opposite to the visual displacement. Prism adaptation experiments have shown that a higher number of interactions lead to an increased magnitude and persistence of the aftereffect. The aim of the present study was to investigate this relationship in virtual reality. After baseline measurement, the virtual environment was displaced visually. During this adaptation phase, the participants performed either zero, five, or thirty-five pointing movements. Afterwards, all participants performed the pointing movements without the visual displacement in the virtual environment. Performing five pointing movements during the adaptation phase was already sufficient to produce an aftereffect. With thirty-five pointing movements, both magnitude and persistence of the aftereffect increased. These results replicate studies of prism adaptation. Considering this, we briefly discuss the suitability of virtual reality as a research tool to study prism adaptation.

Chronic wounds depict a silent epidemic challenging medical professionals worldwide. Regenerative medicine uses adipose-derived stem cells (ADSC) in promising new therapies. In this study, platelet lysate (PL) as a xenogen-free substitute for foetal bovine serum (FBS) in ADSC culture was used to create an ADSC secretome containing cytokines for optimal wound healing conditions. The ADSC secretome was tested on keratinocytes for migrational behaviour and viability. Therefore, human ADSC were characterized under FBS (10%) and PL (5% and 10%) substitution, regarding morphology, differentiation, viability, gene and protein expression. ADSC were then cultured in 5% PL and their secretome was used for stimulation of keratinocyte migration and viability. To enhance the effect, ADSC were treated with Epithelial Growth Factor (EGF, 100 ng/mL) and hypoxia (1% O₂). In both PL and FBS groups, ADSC expressed typical stem cell markers. PL induced a significantly higher increase in cell viability compared to FBS substitution. ADSC secretome contained various beneficial proteins which enhance the wound healing capacity of keratinocytes. This could be optimized treating ADSC with hypoxia and EGF. In conclusion, the study shows that ADSC cultivated in 5 % PL can effectively support wound healing conditions and can be considered as a promising new therapy for individual treatment of chronic wound disorders.

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