Controlling the Sense of Embodiment for Virtual Avatar Applications: Methods and Empirical Study.

BACKGROUND: The sense of embodiment (SoE) is the feeling of one's own body, and research on the SoE extends from the rubber hand illusion to the full-body ownership illusion with a virtual avatar. OBJECTIVE: The key to utilizing a virtual avatar is understanding and controlling the SoE, and it can be extended to several medical applications. In this study, we aimed to clarify these aspects by considering the following three subcomponents of SoE: sense of agency, ownership, and self-location. METHODS: We defined a human avatar (HA), point light avatar (PLA), and out-of-body point light avatar (OBPLA) and compared them in three user studies. In study 1, 28 participants were recruited and the three avatar conditions (HA, PLA, and OBPLA) were compared. In study 2, 29 new participants were recruited, and there were two avatar conditions (HA ad PLA) and two motion synchrony conditions (synchrony and asynchrony). In study 3, 29 other participants were recruited, and there were two avatar conditions (PLA and OBPLA) and two motion synchrony conditions (synchrony and asynchrony). Dependent measures included sense of agency, ownership, and self-location; emotional response; presence; and simulator sickness. RESULTS: The findings of study 1 showed that the three avatar generation methodologies can control the sense of ownership and self-location in a stepwise manner while maintaining a high sense of agency. In studies 2 and 3, we found dependencies among the three subcomponents of SoE and observed that they affected users' subjective experiences. CONCLUSIONS: Our findings may have implications for boosting the effects of virtual avatar applications in medical areas, by understanding and controlling the SoE with a full-body illusion.

Role of nociceptin/orphanin FQ and nociceptin opioid peptide receptor in depression and antidepressant effects of nociceptin opioid peptide receptor antagonists.

Nociceptin/orphanin FQ (N/OFQ) and its receptor, nociceptin opioid peptide (NOP) receptor, are localized in brain areas implicated in depression including the amygdala, bed nucleus of the stria terminalis, habenula, and monoaminergic nuclei in the brain stem. N/OFQ inhibits neuronal excitability of monoaminergic neurons and monoamine release from their terminals by activation of G protein-coupled inwardly rectifying K+ channels and inhibition of voltage sensitive calcium channels, respectively. Therefore, NOP receptor antagonists have been proposed as a potential antidepressant. Indeed, mounting evidence shows that NOP receptor antagonists have antidepressant-like effects in various preclinical animal models of depression, and recent clinical studies again confirmed the idea that blockade of NOP receptor signaling could provide a novel strategy for the treatment of depression. In this review, we describe the pharmacological effects of N/OFQ in relation to depression and explore the possible mechanism of NOP receptor antagonists as potential antidepressants.

Large-scale surveillance study of the safety and effectiveness of entecavir in Korean patients with chronic hepatitis B.

BACKGROUND/AIMS: Entecavir (ETV) is effective and safe antiviral agent against hepatitis B virus (HBV) in clinical and real-world setting but, most studies were performed in single institute or have limitation in patient's number. A large-scale nation-wide real-world surveillance study was carried out to investigate safety, efficacy and clinical effectiveness of ETV in Korean patients with chronic hepatitis B (CHB). METHODS: Between 2006 and 2012, 3,444 patients were enrolled from 132 Korean institutions. For the safety assessment, investigators recorded the occurrence of observed and patient-reported adverse events (AEs), as well as laboratory abnormalities. Efficacy, which consisted of change in HBV DNA and alanine aminotransferase (ALT), was evaluated in patients who had received at least 16 weeks of ETV treatment. Overall clinical effectiveness, based on improvement of ALT, HBV DNA and patient's symptoms, was evaluated by physicians. RESULTS: Of the patients, 3,367 were evaluated for safety and 3,115 for efficacy and clinical effectiveness. Three hundred and eighty AEs were reported in 255 cases (7.57%), and 67 adverse drug reactions in 54 cases (1.6%). Serious AEs (SAE) were 19 events in nine cases (0.27%). Serious adverse drug reactions (SADR) were three events in two cases (0.06%), and unexpected SAE/SADR were three events in two cases (0.06%). Medical history and concomitant medications were factors inf luencing incidence rates of AEs. Overall clinical effectiveness rate was 96.53%, which was clinically assessed as marked improved or improved state. CONCLUSIONS: This study showed that ETV was well tolerated and clinically effective in Korean patients with CHB in a real-world nation-wide setting.

Improving osteoblast functions and bone formation upon BMP-2 immobilization on titanium modified with heparin.

The aim of this study was to develop bone morphogenetic protein-2 (BMP-2) immobilization on titanium (Ti) modified by heparin for improving osteoblast function in vitro and bone formation in vivo. The Ti surface was first modified with heparin and then immobilized with BMP-2 (BMP-2/Hep-Ti). The Ti and modified Ti were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and contact angle. In vitro studies demonstrated that osteoblasts cultured on BMP-2/Hep-Ti substrate increased ALP activity, calcium deposition, osteocalcin (OCN) and osteopontin (OPN) levels as compared to those cultured on Ti or BMP-2/Ti. In addition, intra-thread bone density and bone to implant contact ratio of BMP-2/Hep-Ti were significantly greater than those of Ti in the in vivo study. In conclusion, BMP-2 immobilized Ti modified heparin implants seemed to be a suitable delivery system for BMP-2 to improve osteoblast functions and new bone formation at the defect area around an implant.

The hemostatic effect of endoscopic sodium hyaluronate injection in peptic ulcer bleeding.

BACKGROUND/AIMS: Endoscopic injection therapy is a well-established method of controlling peptic ulcer bleeding but it is not clear which agent would be the best choice for injection material. In this study, we evaluated the effect of Sodium Hyaluronate for control of ulcer bleeding. METHODOLOGY: The subjects consisted of 26 patients with major peptic ulcer hemorrhage from June 2000 to August 2001. There were 17 gastric ulcers, 7 duodenal ulcers and 2 ulcers at anastomosis site. According to modified Forrest classifications, there were 7 active bleeding (spurting, 3; oozing, 4) and 19 stigmata of recent hemorrhage (visible vessel, 14; fresh blood clots, 5). Sodium Hyaluronate-saline solution was injected to control the bleeding. The initial and permanent hemostatic rate, rebleeding rate, and other complications were retrospectively evaluated. RESULTS: The initial hemostatic rate was 25/26 (96.2%) and re-bleeding rate 3/26 (11.5%). The success rate of the second trial of Sodium Hyaluronate injection was 3/3 (100%). Overall, the permanent hemostatic rate was 25/26 (96.2%) and there were no complications related to Sodium Hyaluronate injection. CONCLUSIONS: Sodium Hyaluronate is an excellent candidate agent for endoscopic injection therapy because of its convenience and safety. Further prospective randomized trials with other hemostatic methods are needed.