To characterize skin ulcers for bacterial infection, quantitative ultrasound (QUS) parameters were estimated by the multiple statistical analysis of the echo amplitude envelope based on both Weibull and generalized gamma distributions and the ratio of mean to standard deviation of the echo amplitude envelope. Measurement objects were three rat models (noninfection, critical colonization, and infection models). Ultrasound data were acquired using a modified ultrasonic diagnosis system with a center frequency of 11 MHz. In parallel, histopathological images and two-dimensional map of speed of sound (SoS) were observed. It was possible to detect typical tissue characteristics such as infection by focusing on the relationship of QUS parameters and to indicate the characteristic differences that were consistent with the scatterer structure. Additionally, the histopathological characteristics and SoS of noninfected and infected tissues were matched to the characteristics of QUS parameters in each rat model.

Purpose: This study evaluated the in vitro antibacterial activity and cytotoxicity of various commercially available silver-containing dressings (Ag dressing). at immersion periods of 6, 24, and 48 hours. The antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa were accessed by a disc diffusion test. The cytotoxicity was evaluated using V79 cells, by an extraction method. Methods Results:The cytotoxicity was not a monotonic function of the antibacterial activity among the Ag dressings and could not be simply explained by Ag + -release properties. Biohesive Ag was regarded as a slow-release Ag dressing, showing the lowest cytotoxicity, while the antibacterial activity was classified as "strong" or "significant" against the two species of bacteria. Aquacel Ag and Algisite Ag showed higher antibacterial activity and cytotoxic effects, which were supported by the higher Ag + release. Mepilex Ag showed the highest release of Ag + , and the cytotoxicity was the highest among the Ag dressings. However, the antibacterial activity was classified as "significant" or "no activity" for P. aeruginosa and S. aureus, respectively. PolyMem Ag showed the lowest Ag + release, and the antibacterial activity classified as "significant" or "no activity"for S. aureus and P. aeruginosa, respectively, whereas the cytotoxicity was similar to those of Aquacel Ag and Algisite Ag. Conclusion:The efficacy and adverse effects of the Ag dressings revealed differences that should be considered by clinicians during wound management.

Polymeric systems for antibacterial wound dressings require chemical reactions or syntheses for attaching or incorporating antibacterial moieties into polymer backbones. However, these materials often fail to satisfy the basic requirements, such as easy and inexpensive synthesis. We speculated that a positively charged organic antibacterial agent would be attracted to the polar groups of poly(vinyl alcohol) (PVA) hydrogels and would show suppressed release. PVA hydrogels containing cetylpyridinium chloride (CPC) were prepared by c irradiation. CPC was barely released from the hydrogels, probably because of electrostatic interactions, and was stable upon c irradiation. The suppressed release of CPC conferred antibacterial activity against Escherichia coli to the surface of the hydrogels, whereas no inhibition zone was observed around the hydrogels. The CPC-containing PVA hydrogels were easy to prepare and contained known and safe materials. The simplicity and safety of this procedure for achieving the suppressed release of antibacterial agents were advantages of these CPC-containing PVA hydrogels.

Background: Numerous clinical challenges regarding adhesive dressings have shown that using an adhesive dressing could minimize or prevent superficial skin loss in patients at risk of developing pressure ulcers. However, evidence that polyurethane film dressings and ceramide 2-containing hydrocolloid dressing can reduce the risk of pressure ulcer development in highrisk patients undergoing surgery is limited. Therefore, we assessed the effects of application of these dressings for reducing the risk of pressure ulcer development in these patients and identified other risk factors. Methods: A matched case-control study was conducted involving 254 patients at high risk for pressure ulcer development at one acute care hospital in Japan. No patients in this study had a pressure ulcer at the start of the study. Thirty-one patients developed a pressure ulcer during surgery, and these patients were defined as cases. Controls were randomly matched for sex and age (±4 years), from which 62 patients were selected. Medical records were obtained for preoperative factors, including age, sex, body mass index, diabetes mellitus, albumin, total protein, C-reactive protein, white cell count, red cell count, and hemoglobin, and for intraoperative factors, including dressing application, operation time, body position, and surgery type. The odds ratio (OR) and 95% confidence interval (CI) were determined to identify risk factors for pressure ulcer development in patients undergoing surgery. Results: By multiple logistic regression analysis, there was a significantly reduced risk of pressure ulcer development for patients who had dressing applications as compared with those without dressing applications (OR 0.063; 95% CI 0.012-0.343; P=0.001). Prone position (OR 8.791; 95% CI 1.630-47.400; P=0.01), prolonged operation time (OR 1.684; 95% CI 1.189-2.385, P=0.003), and reduced body mass index (OR 0.774; 95% CI 0.584-0.948; P=0.02) were also significant predictive risk factors for development of a pressure ulcer. Conclusion: Application of film dressing and ceramide 2-containing hydrocolloid dressing reduced the risk of pressure ulcer development in high-risk patients undergoing surgery.

Purpose: Previous studies on pressure injury prevention using questionnaire surveys have targeted physicians and nurses working in hospitals. However, few have administered surveys to social welfare professionals at home care. Thus, this study aimed to investigate the current level of knowledge and practice regarding pressure injury prevention among Japanese care managers. Patients and methods: A cross-sectional study among care managers working in a Japanese city was performed from June to July 2016. Data were collected using a questionnaire to assess the participants' knowledge of and practice for pressure injury prevention. The questionnaire included 1) measures of demographic characterization, 2) measures of knowledge, 3) measures of practice, and 4) measures of the difficulties of using pressure injury risk assessment scales. Results: A total of 48 participants were analyzed (response rate: 55%). The overall knowledge and practice scores were 78.6% and 61.8%, respectively. The percentages of participants who knew the risk assessment scales were 38%, 26%, and 13% for the Braden scale, the Ohura-Hotta scale, and the University of Kanazawa scale, respectively. We also observed that 50% of the participants in this study believed that the use of risk assessment scales in daily practice in home care may be difficult. Conclusion: Through the results of this questionnaire survey, we concluded that the current levels of knowledge and practice regarding pressure injury prevention among the care managers participating in our study were "moderate" and "low", respectively. Low scores were obtained for knowledge with respect to the question, "Using risk assessment scales". We will develop a new risk assessment scale as a bridge between both medical professionals and social welfare professionals. Practically, the authors recommend care managers should receive continuous education and practical training for pressure injury prevention in a home care setting.