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Abstract Background: Wayfinding has been adopted in several intense evacuation and navigation simulations; however, the use of biometric measurements for characterizing physiological outcomes has been somewhat overlooked and applied only under limited laboratory conditions. Methods: Twenty-four participants took part in a virtual reality (VR) experiment using a wayfinding installation with the Oculus Rift S head-mounted display (HMD). They were immersed in a simulation of a burning underground parking lot and tasked to navigate to the exit. The purpose of this research was to investigate the high-level effect of wayfinding assistive lights on behavioral, physiological, and psychological outcomes. Participants were split into two groups: the control group was exposed to a scene without assistive lights, and the experimental group was exposed to the same scene with assistive lights. Results: Results indicate there was no statistically significant difference between the groups in traveled distance, pauses, turns, or game completion time. Curiously, differences between the two groups in heart rate (HR) outcomes were found to be statistically significant, with subjects in the control group displaying an increasing HR trend during simulation. Conclusions: This finding, in accordance with previous studies that have shown the efficacy of landmarks and wayfinding affordances in reducing cognitive demands, suggests that assistive lights might contribute to improved brain wiring connectivity during the game. We discuss these findings in the context of a rich wayfinding affordances literature.
Cancer is among the leading causes of death worldwide. One of the most challenging obstacles in cancer treatment is multidrug resistance (MDR). Overexpression of P-glycoprotein (P-gp) is associated with MDR. The growing incidence of cancer and the development of MDR drive the search for novel and more effective anticancer drugs to overcome the MDR problem. Royleanones are natural bioactive compounds frequently found in Plectranthus spp. The cytotoxic diterpene 6,7-dehydroroyleanone (1) is the main component of the P. madagascariensis (Pers.) Benth. essential oil, while 7α-acetoxy-6β-hydroxyroyleanone (2) can be isolated from acetonic extracts of P. grandidentatus Gürke. The reactivity of the natural royleanones 1 and 2 was explored to obtain a small library of new P-gp inhibitors. Four new derivatives (6,7-dehydro-12-O-tert-butyl-carbonate-royleanone (20), 6,7-dehydro-12-O-methylroyleanone (21), 6,7-dehydro-12-O-benzoylroyleanone (22), and 7α-acetoxy-6β-hydroxy-12-O-benzoylroyleanone (23) were obtained as pure with overall modest to excellent yields (21–97%). P-gp inhibition potential of the derivatives 20–23 was evaluated in human non-small cell lung carcinoma NCI-H460 and its MDR counterpart NCI-H460/R with the P-gp overexpression, through MTT assay. Previously prepared diterpene 7α-acetoxy-6β-benzoyloxy-12-O-(4-chloro)benzoylroyleanone (4), has also been tested. The P-gp inhibiting effects of compounds 1–4 were also assessed through a Rhodamine 123 accumulation assay. Derivatives 4 and 23 have significant P-gp inhibitory potential. Regarding stability and P-gp inhibition potential, results suggest that the formation of benzoyl esters is a more convenient approach for future derivatives with enhanced effect on the cell viability decrease. Compound 4 presented higher anti-P-gp potential than the natural diterpenes 1, 2, and 3, with comparable inhibitory potential to Dexverapamil. Moreover, derivative 4 showed the ability to sensitize the resistant NCI-H460/R cells to doxorubicin.