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As sarcomeres produce the force necessary for contraction, assessment of sarcomere order is paramount in evaluation of cardiac and skeletal myocytes. The uniaxial force produced by sarcomeres is ideally perpendicular to their z-lines, which couple parallel myofibrils and give cardiac and skeletal myocytes their distinct striated appearance. Accordingly, sarcomere structure is often evaluated by staining for z-line proteins such as α-actinin. However, due to limitations of current analysis methods, which require manual or semi-manual handling of images, the mechanism by which sarcomere and by extension z-line architecture can impact contraction and which characteristics of z-line architecture should be used to assess striated myocytes has not been fully explored. Challenges such as isolating z-lines from regions of off-target staining that occur along immature stress fibers and cell boundaries and choosing metrics to summarize overall z-line architecture have gone largely unaddressed in previous work. While an expert can qualitatively appraise tissues, these challenges leave researchers without robust, repeatable tools to assess z-line architecture across different labs and experiments. Additionally, the criteria used by experts to evaluate sarcomeric architecture have not been well-defined. We address these challenges by providing metrics that summarize different aspects of z-line architecture that correspond to expert tissue quality assessment and demonstrate their efficacy through an examination of engineered tissues and single cells. In doing so, we have elucidated a mechanism by which highly elongated cardiomyocytes become inefficient at producing force. Unlike previous manual or semi-manual methods, characterization of z-line architecture using the metrics discussed and implemented in this work can quantitatively evaluate engineered tissues and contribute to a robust understanding of the development and mechanics of striated muscles., Competing Interests: The authors have declared that no competing interests exist.

Background: Written and video approaches to donor education have been shown to enhance donation attitudes and intentions to give blood, particularly when the information provides specific coping suggestions for donation-related concerns. This study extends this work by comparing Web-based approaches to donor preparation among donors and nondonors., Study Design and Methods: Young adults (62% female; mean [±SD] age, 19.3 [±1.5] years; mean [range] number of prior blood donations, 1.1 [0-26]; 60% nondonors) were randomly assigned to view 1) a study Web site designed to address common blood donor concerns and suggest specific coping strategies (n = 238), 2) a standard blood center Web site (n = 233), or 3) a control Web site where participants viewed videos of their choice (n = 202). Measures of donation attitude, anxiety, confidence, intention, anticipated regret, and moral norm were completed before and after the intervention., Results: Among nondonors, the study Web site produced greater changes in donation attitude, confidence, intention, and anticipated regret relative to both the standard and the control Web sites, but only differed significantly from the control Web site for moral norm and anxiety. Among donors, the study Web site produced greater changes in donation confidence and anticipated regret relative to both the standard and the control Web sites, but only differed significantly from the control Web site for donation attitude, anxiety, intention, and moral norm., Conclusion: Web-based donor preparation materials may provide a cost-effective way to enhance donation intentions and encourage donation behavior., (© 2012 American Association of Blood Banks.)

Background: Blood donors may hold conflicting thoughts about future donation. While they may perceive the direct benefit to themselves and others, they often report compelling reasons not to give again. As a result the standard encouragements to return may not be sufficient to motivate some donors. This study examined the effects of a postdonation adapted motivational interview (AMI) on blood donor attitudes and repeat donation behavior., Study Design and Methods: Donors (n = 215) were randomly assigned to either an AMI or a no-interview control group. Approximately 1 month after their index donation, donors in the AMI group completed a brief telephone interview to clarify individual-specific motivations and values concerning blood donation and address potential barriers. They were then asked to complete questionnaires regarding donation attitudes, anxiety, self-efficacy, and intention to donate. Donors in the control group were also contacted 1 month after donation and asked to complete the same series of questionnaires., Results: Donors in the AMI group reported greater intention to provide a future donation (F = 8.13, p < 0.05), more positive donation attitudes (F = 4.59, p < 0.05), and greater confidence in their ability to avoid adverse reactions (F = 10.26, p < 0.01). Further, AMI was associated with higher rates of attempted donation at 12 months (odds ratio, 2.48; 95% confidence interval, 1.27-4.87)., Conclusion: Application of an AMI may be an effective strategy to increase the donor pool by enhancing retention of existing donors., (© 2010 American Association of Blood Banks.)