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Chang Yao,1 Matt Hedrick,1 Gyan Pareek,2 Joseph Renzulli,2 George Haleblian,2 Thomas J Webster3 1Nanovis LLC, West Lafayette, IN, 2Section of Minimally Invasive Urology, Alpert Medical School, Brown University, Providence, RI, 3Department of Chemical Engineering and Program in Bioengineering, Northeastern University, Boston, MA, USA Abstract: Although showing much promise for numerous tissue engineering applications, polyurethane and poly-lactic-co-glycolic acid (PLGA) have suffered from a lack of cytocompatibility, sometimes leading to poor tissue integration. Nanotechnology (or the use of materials with surface features or constituent dimensions less than 100 nm in at least one direction) has started to transform currently implanted materials (such as polyurethane and PLGA) to promote tissue regeneration. This is because nanostructured surface features can be used to change medical device surface energy to alter initial protein adsorption events important for promoting tissue-forming cell functions. Thus, due to their altered surface energetics, the objective of the present in vivo study was to create nanoscale surface features on a new polyurethane and PLGA composite scaffold (by soaking the polyurethane side and PLGA side in HNO3 and NaOH, respectively) and determine bladder tissue regeneration using a minipig model. The novel nanostructured scaffolds were further functionalized with IKVAV and YIGSR peptides to improve cellular responses. Results provided the first evidence of increased in vivo bladder tissue regeneration when using a composite of nanostructured polyurethane and PLGA compared with control ileal segments. Due to additional surgery, extended potentially problematic healing times, metabolic complications, donor site morbidity, and sometimes limited availability, ileal segment repair of a bladder defect is not optimal and, thus, a synthetic analog is highly desirable. In summary, this study indicates significant promise for the use of nanostructured polyurethane and PLGA composites to increase bladder tissue repair for a wide range of regenerative medicine applications, such as regenerating bladder tissue after removal of cancerous tissue, disease, or other trauma. Keywords: polyurethane, poly-lactic-co-glycolic acid, nanotechnology, nanostructured features, in vivo

Margot Kelly-Hedrick,1 Kaitlin M Stouffer,2 Elizabeth Benskin,3 Suzy Wolffe,3 Norah Wilson,4 Margaret S Chisolm5 1Duke University School of Medicine, Durham, NC, USA; 2Johns Hopkins University School of Medicine, Baltimore, MD, USA; 3Department of Education, The Baltimore Museum of Art, Baltimore, MD, USA; 4Krieger School of Arts and Sciences, Johns Hopkins University, Baltimore, MD, USA; 5Department of Psychiatry and Behavioral Services, and of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USACorrespondence: Margot Kelly-Hedrick, Duke University School of Medicine, DUMC 2927, 40 Duke Medicine Circle, Durham, NC, 27710, USA, Email margot.kellyhedrick@duke.eduIntroduction: Health professions educators are increasingly recognizing the fundamental role the arts and humanities play in professional identity formation; however, few reports exist of programs designed specifically for pre-health professional students.Methods: We designed and delivered four, 2.5-h sessions for pre-health professions students at a local museum in partnership with museum educators. Participants were invited to respond to a follow-up survey asking about their perceived insights from and importance of the session. We used descriptive statistics and thematic content analysis for quantitative and qualitative data, respectively.Results: Ten of the participants responded to the survey (n=10/23, response rate=43%) and all supported the integration of such an experience in their pre-health curriculum. The qualitative analysis of responses to the open-ended item about any insights gained from participation in the program revealed three themes: cultivation of the health professional, personal growth, and awareness and appreciation of multiple perspectives.Discussion: Participants who responded to our survey drew meaningful connections to the relevance of these sessions to their development as future professionals.Keywords: pre-health, pre-medical education, arts and humanities, art museum

The use of historical and ancient tissue samples for genetic analysis is increasing, with ever greater numbers of samples proving to contain sufficient mitochondrial and even nuclear DNA for multilocus analysis. DNA yield, however, remains highly variable and largely unpredictable based solely on sample morphology or age. Quantification of DNA from historical and degraded samples can greatly improve efficiency of screening DNA extracts prior to attempting sequencing or genotyping, but requires sequence-specific quantitative polymerase chain reaction (qPCR) based assays to detect such minute quantities of degraded DNA. We present two qPCR assays for marine mammal DNA quantification, and results from analysis of DNA extracted from preserved soft tissues, bone, baleen, and tooth from several cetacean species. These two assays have been shown to amplify DNA from 26 marine mammal species representing 12 families of pinnipeds and cetaceans. Our results indicate that different tissues retain different ratios of mitochondrial to nuclear DNA, and may be more or less suitable for analysis of nuclear loci. Specifically, historical bone and tooth samples average 60-fold higher ratio of mitochondrial DNA to nuclear DNA than preserved fresh soft tissue, and the ratio is almost 8000-fold higher in baleen. [ABSTRACT FROM AUTHOR]

Animal and early clinical studies have provided evidence suggesting that intracoronary administration of autologous bone marrow-derived cells results in improved outcome following myocardial infarction. Animal studies with cultured marrow stromal cells (MSC) have provided similar data. Cells with properties that are similar to MSC have been identified in adipose tissue. Other groups have demonstrated in vivo differentiation of adipose tissue-derived cells (ADC) into cells exhibiting biochemical and functional markers of cardiac myocytes, including spontaneous beating. Based on these observations, the objective of the present study was to determine whether ADC might undergo similar differentiation in vivo in the context of myocardial injury. ADC were isolated from subcutaneous adipose tissue of Rosa26 mice (which express the beta-galactosidase transgene in almost every tissue) and injected into the intraventricular chamber of B6129S recipient mice immediately following induction of myocardial cryoinjury. Groups of recipients were euthanized at 24 hours, 7 and 14 days post surgery and examined for the presence of donor-derived cells within the heart. Beta-gal positive cells were identified in the infarcts of ADC-treated animals. No staining was observed in uninjured myocardium or in infarcts of control animals. Immunohistochemical analysis revealed co-expression of beta-gal with Myosin Heavy Chain, Nkx2.5 and with Troponin I. Co-expression of beta-galactosidase with Connexin 43, CD31, von Willebrand factor, MyoD or CD45 was not detected. Thus, these data indicate that adipose tissue contains a population of cells that has the ability to engraft injured myocardium and that this engraftment is associated with expression of cardiomyocytic markers by donor-derived cells. [ABSTRACT FROM AUTHOR]