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The current study describes the synthesis, physicochemical characterization and cytotoxicity evaluation of a new series of pyrrole derivatives in order to identify new bioactive molecules. The new pyrroles were obtained by reaction of benzimidazolium bromide derivatives with asymmetrical acetylenes in 1,2-epoxybutane under reflux through the Huisgen [3 + 2] cycloaddition of several ylide intermediates to the corresponding dipolarophiles. The intermediates salts were obtained from corresponding benzimidazole with bromoacetonitrile. The structures of the newly synthesized compounds were confirmed by elemental analysis, spectral techniques (i.e., IR, 1H-NMR and 13C-NMR) and single-crystal X-ray analysis. The cytotoxicity of the synthesized compounds was evaluated on plant cells (i.e., Triticum aestivum L.) and animal cells using aquatic crustaceans (i.e., Artemia franciscana Kellogg and Daphnia magna Straus). The potential antitumor activity of several of the pyrrole derivatives was studied by performing in vitro cytotoxicity assays on human adenocarcinoma-derived cell lines (i.e., LoVo (colon), MCF-7 (breast), and SK-OV-3 (ovary)) and normal human umbilical vein endothelial cells (HUVECs). The obtained results of the cytotoxicity assessment indicated that the tested compounds had nontoxic activity on Triticum aestivum L., while on Artemia franciscana Kellogg nauplii, only compounds 2c and 4c had moderate toxicity. On Daphnia magna, 4b and 4c showed high toxicity; 2a, 2b, and 2c moderate to high toxicity; only 4a and 4d were nontoxic. The compound-mediated cytotoxicity assays showed that several pyrrole compounds demonstrated dose- and time-dependent cytotoxic activity against all tested tumor cell lines, the highest antitumor properties being achieved by 4a and its homologue 4d, especially against LoVo colon cells.

The proliferation of high resolution and affordable virtual reality (VR) headsets is quickly making room-scale VR experiences available in our homes. Most VR experiences strive to achieve complete immersion by creating a disconnect from the real world. However, due to the lack of a standardized notification management system and minimal context awareness in VR, an immersed user may face certain situations such as missing an important phone call (digital scenario), tripping over wandering pets (physical scenario), or losing track of time (temporal scenario). In this paper, we present the results of 1) a survey across 61 VR users to understand common interruptions and scenarios that would benefit from some form of notifications; 2) a design exercise with VR professionals to explore possible notification methods; and 3) an empirical study on the noticeability and perception of 5 different VR interruption scenarios across 6 modality combinations (e.g., audio, visual, haptic, audio + haptic, visual + haptic, and audio + visual) implemented in Unity and presented using the HTC Vive headset. Finally, we combine key learnings from each of these steps along with participant feedback to present a set of observations and recommendations for notification design in VR.

Since cancer is a cellular disease, it is essential to identify the development stages and use the information in the prediction, prevention, early detection and design of drug targets. Colon cancer represents a malignancy with high incidence and mortality throughout the world, its etiology involving many genetic, immunological and biochemical factors. 5-fluorouracyl (5-FU) is one of the most effective anti-cancer agents used in the treatment of colorectal cancers, but tumor chemoresistance is a major limiting factor of its use. In order to choose the most effective chemotherapeutic doses of 5-FU, and thereby diminish the side-effects, we tried to modulate the anticancer properties of 5-FU by adding dietary natural compounds. The study focused on the role of natural compounds as resveratrol (RSV) in sensitization of LoVo human colon adenocarcinoma cell line to 5-FU action. Real-time cell analysis (RTCA) by xCELLigence System was used to continuously monitor the cytotoxic effects of drug treatments on LoVo cells. RTCA allowed us to choose the proper concentrations for further end-point assays, such as flow-cytometry techniques used for the evaluation of apoptotic events, progression through cell cycle phases or nuclear antigen expression of compound-treated LoVo cells. Data obtained showed additional effects of RSV to 5-FU treatments on the increase ofapoptotic events, and suggested alternative approaches to obtain a stronger antitumor response, and diminished side-effects when low concentrations of anti-cancer drugs are used. Modulation of the mechanisms of programmed cell death process seem to be of great importance for malignant transformation, and therefore for anti-cancer therapeutic approaches.