RSS 1.0URSA: University Research, Scholarship, and Archives
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Alma - OAI Test CThis is a test of the emergency broadcast system.
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Alma - OAI Test #2Disco Inferno and the Chocolate Factory
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Effect of Calcitriol on the Immunomodulatory Properties and Hyaluronic Acid Metabolic Pathways of Human Mesenchymal Stem CellsMesenchymal stem cells (MSCs) are non-hematopoietic stem cells which have remarkable immunomodulatory and tissue reparative properties, sparking clinical interest in their use in regenerative medicine. MSC-mediated immunomodulation occurs primarily via production of soluble factors like indolamine-2,3-dioxygenase (IDO), programmed death ligand-1 (PDL-1), prostaglandin E2 (PGE2), among others which function to inhibit effector immune cell function while promoting regulatory subtypes. Our lab focuses on the role of hyaluronic acid (HA) metabolism and signaling through HA receptor, CD44, in MSC’s ability to modulate the immune system and promote tissue repair. Data from our lab has demonstrated alterations in HA metabolism, production, and signaling in MSCs that have been primed with an inflammatory signal. Emerging research has suggested that calcitriol, the biologically active form of Vitamin D, may modulate soluble factor production by MSCs in response to inflammation. Taken together, we then hypothesized that calcitriol may also augment HA metabolic pathways. We utilized secretomes from Staphylococcal enterotoxin B (SEB)-activated peripheral blood mononuclear cells (PBMCs) to simulate the inflammatory microenvironment. In PBMC supernatant-activated MSCs we saw a consistent upregulation in gene expression of CD44, HA synthase isoform HAS-3, IDO-1, and PDL-1. Preliminary data suggests possible alterations in the molecular weight of hyaluronic acid secreted by activated MSCs when treated with calcitriol and PBMC supernatant when visualized by gel electrophoresis, though further replicates are needed. xi On its own, calcitriol was not able to modulate the alterations seen in HA metabolism in activated MSCs, as there was no statistically significant change in HAS3 gene expression between calcitriol and vehicle at 24-hour time-points. Though, calcitriol was shown to decrease total HA production in activated MSCs, as well as partially restore high molecular weight HA in PBMC supernatant- activated MSCs. Calcitriol was not demonstrated to meaningfully alter gene expression of IDO-1 or PDL-1 compared to PBMC supernatant-treated cells, suggesting that calcitriol does not affect MSC activation by inflammatory stimuli. However, optimization of the calcitriol delivery process and exposure time is necessary. Preliminary results following optimization of calcitriol dose and timing demonstrate a significant alteration in expression of HAS3, though further replicates are needed to confirm this effect. Additional studies investigating the effects of secretomes from MSCs treated with calcitriol on immune cell activity, and co-culturing experiments between MSCs and immune cells in the presence of calcitriol may provide more insight into the role of calcitriol and its effect on the immunomodulatory properties of MSCs.
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Nursing Student Perceptions of Presence in a Virtual Learning Environment: A Qualitative Description StudyMultifaceted approaches to learning are used for educating student nurses. One common teaching modality in nursing education, simulation, provides hands-on experiences in a safe environment to prepare student nurses for professional roles. High quality simulation standards recommend an engaging immersive experience, with physical, emotional, and conceptual fidelity to clinical practice. Presence is the perception of being there in a simulation as if it were real. Studies have reported improved learning outcomes with increased sense of presence. A simulation modality seldom used in nursing education is virtual reality simulation (VR-Sim) a three dimensional, immersive experience. VR-Sim with head mounted visual and haptic enhancements has the potential to increase presence and improve learning. Student perceptions of presence in VR-Sim is unknown. The purpose of this study was to explore student nurses’ perceptions of presence during simulation. A qualitative description design included a VR-Sim of a patient needing cardiopulmonary resuscitation (CPR). Each participant (N=11) performed two repetitions in the VR-Sim followed by debriefing and a guided interview. The conceptual framework for the study was informed by extant literature including theoretical frameworks. Two research questions guided the study to 1) explore student perceptions of presence in VR-Sim and 2) align findings with current theories of simulation and presence. Braun and Clarke’s (2006) steps for theme development and Saldaña’s (2016) coding informed the data analysis. For Research Question 1, three themes and eight subthemes described participants perceptions of being there in the VR-Sim environment. Findings showed all participants reported experiencing presence during the simulation (Theme: What Brought Me In, What Brought Me Out), but glitches, feel of compressions, and sensing the real physical environment outside the simulation interrupted the experience of presence (Theme: Issues in VR-Sim). Additionally, participants described the experience of learning CPR with the VR-Sim (Theme: Higher Level of Learning). For Research Question 2, the main constructs from the extant theories aligned with the perceptions of participants including ideas about presence, fidelity, individual factors, learning outcomes, and collaboration. The study conceptual model provided a sound framework for continued research of the efficacy of VR-Sim in nursing education.
