Poly(methacrylic acid -co- methyl methacrylate) beads were previously shown to have a therapeutic effect on wound closure through the promotion of angiogenesis. However, it was unclear how this polymer elicited its beneficial properties. The goal of this thesis was to characterize the host response to MAA beads by identifying molecules of interest involved in MAA-mediated angiogenesis (in comparison to poly(methyl methacrylate) beads, PMMA). Using a model of diabetic wound healing and a macrophage-like cell line (dTHP-1), eight molecules of interest were identified in the host response to MAA beads. Gene and/or protein expression analysis showed that MAA beads increased the expression of Shh, IL-1β, IL-6, TNF-α and Spry2, but decreased the expression of CXCL10 and CXCL12, compared to PMMA and no beads. MAA beads also appeared to modulate the expression of OPN. In vivo, the global gene expression of OPN was increased in wounds treated with MAA beads, compared to PMMA and no beads. In contrast, dTHP-1 decreased OPN gene expression compared to PMMA and no beads, but expressed the same amount of secreted OPN, suggesting that the cells decreased the expression of the intracellular isoform of OPN. Interestingly, MAA beads had no effect on the expression of pro-angiogenic growth factors VEGF, bFGF and PDGF-B in vivo or in vitro, suggesting that MAA beads do not induce angiogenesis by simply increasing the expression of pro-angiogenic factors, but use more subtle mechanisms. It was hypothesized that these mechanisms may involve modulation of toll-like receptor signaling in macrophages interacting with the protein layer adsorbed on to MAA beads, in a manner distinct from PMMA beads and no beads. Taken together, the results suggest that MAA beads promote angiogenesis through increased expression of Shh, decreased expression of CXCL10 and modulation of the expression of OPN, but not through increased expression of typical pro-angiogenic growth factors. The resulting vessel-rich “alternative foreign body reaction” has exciting clinical implications as the polymer itself was found to exert a therapeutic effect in the absence of bioactive components or transplanted cells. Understanding the mechanism could lead to new applications for this material and others designed on similar principles.

Poly(methacrylic acid -co- methyl methacrylate) beads were previously shown to have a therapeutic effect on wound closure through the promotion of angiogenesis. However, it was unclear how this polymer elicited its beneficial properties. The goal of this thesis was to characterize the host response to MAA beads by identifying molecules of interest involved in MAA-mediated angiogenesis (in comparison to poly(methyl methacrylate) beads, PMMA). Using a model of diabetic wound healing and a macrophage-like cell line (dTHP-1), eight molecules of interest were identified in the host response to MAA beads. Gene and/or protein expression analysis showed that MAA beads increased the expression of Shh, IL-1β, IL-6, TNF-α and Spry2, but decreased the expression of CXCL10 and CXCL12, compared to PMMA and no beads. MAA beads also appeared to modulate the expression of OPN. In vivo, the global gene expression of OPN was increased in wounds treated with MAA beads, compared to PMMA and no beads. In contrast, dTHP-1 decreased OPN gene expression compared to PMMA and no beads, but expressed the same amount of secreted OPN, suggesting that the cells decreased the expression of the intracellular isoform of OPN. Interestingly, MAA beads had no effect on the expression of pro-angiogenic growth factors VEGF, bFGF and PDGF-B in vivo or in vitro, suggesting that MAA beads do not induce angiogenesis by simply increasing the expression of pro-angiogenic factors, but use more subtle mechanisms. It was hypothesized that these mechanisms may involve modulation of toll-like receptor signaling in macrophages interacting with the protein layer adsorbed on to MAA beads, in a manner distinct from PMMA beads and no beads. Taken together, the results suggest that MAA beads promote angiogenesis through increased expression of Shh, decreased expression of CXCL10 and modulation of the expression of OPN, but not through increased expression of typical pro-angiogenic growth factors. The resulting vessel-rich “alternative foreign body reaction” has exciting clinical implications as the polymer itself was found to exert a therapeutic effect in the absence of bioactive components or transplanted cells. Understanding the mechanism could lead to new applications for this material and others designed on similar principles.

Wound-related pain is complex, integrating the experience of noncyclic acute wound pain, cyclic acute wound pain, and chronic wound pain (Krasner 1995). More than 80% of chronic wound patients report pain during wound dressing change. A constellation of physical and psychological factors may be involved in the mediation of pain during wound dressing change. A burgeoning body of evidence suggests the intricate relationship between anxiety and pain. In this study, the attachment framework was examined to determine how personal views of self (attachment anxiety) and others (attachment avoidance) may affect pain during dressing change. Attachment styles are systematic patterns of expectations, emotional reactivity, strategies for distress management and social behaviour that are based on an individual’s belief about the self and others. Internal working models are cognitive-affective schemas that guide the attachment patterns. Purpose: The purpose of this study was to explore the relationship of attachment style and pain during dressing change in an older population. In particular the study focussed on the role that anxiety, anticipatory self reported pain, and behavioural expression of pain play in this relationships. Method: A questionnaire was used in this cross-sectional study to classify 96 older subjects into four different categories of attachment styles. Subjects were asked to rate their levels of anticipatory pain and actual pain levels at different times during wound care using a numerical rating scale. Results: The results indicated that subjects experienced more pain during dressing change than at baseline. Secure subjects reported less pain and anxiety than subjects with other attachment styles. Results of regression analysis indicated that anxiety mediated the relationship between attachment and pain. Conclusion: The results of this study also support the role that attachment plays in the experience of pain in older adults. Clinicians must be cognizant of the impact of personality, anxiety, and anticipation of pain on the actual pain experience.

No description available.

Wound-related pain is complex, integrating the experience of noncyclic acute wound pain, cyclic acute wound pain, and chronic wound pain (Krasner 1995). More than 80% of chronic wound patients report pain during wound dressing change. A constellation of physical and psychological factors may be involved in the mediation of pain during wound dressing change. A burgeoning body of evidence suggests the intricate relationship between anxiety and pain. In this study, the attachment framework was examined to determine how personal views of self (attachment anxiety) and others (attachment avoidance) may affect pain during dressing change. Attachment styles are systematic patterns of expectations, emotional reactivity, strategies for distress management and social behaviour that are based on an individual’s belief about the self and others. Internal working models are cognitive-affective schemas that guide the attachment patterns. Purpose: The purpose of this study was to explore the relationship of attachment style and pain during dressing change in an older population. In particular the study focussed on the role that anxiety, anticipatory self reported pain, and behavioural expression of pain play in this relationships. Method: A questionnaire was used in this cross-sectional study to classify 96 older subjects into four different categories of attachment styles. Subjects were asked to rate their levels of anticipatory pain and actual pain levels at different times during wound care using a numerical rating scale. Results: The results indicated that subjects experienced more pain during dressing change than at baseline. Secure subjects reported less pain and anxiety than subjects with other attachment styles. Results of regression analysis indicated that anxiety mediated the relationship between attachment and pain. Conclusion: The results of this study also support the role that attachment plays in the experience of pain in older adults. Clinicians must be cognizant of the impact of personality, anxiety, and anticipation of pain on the actual pain experience.

The aim of this study was to investigate the effects of various polysaccharides and their breakdown products on the proliferation and migration of cells involved in wound healing, both in vitro and in vivo, with the ultimate aim of developing a commercially viable collagen dressing containing an active polysaccharide fragment which would stimulate the wound healing response to such a degree that good quality and significantly faster healing would take place. Hyaluronic acid (HA), chondroitin sulphate (CS), heparin, Oxidised Regenerated Cellulose (ORC) and pectin were tested in this study. Some HA fragments and CS fragments significantly stimulated (p<O.05) the proliferation of Bovine Aortic Endothelial (BAEC) cells, although other HA or CS fragments were without effect. All HA and CS fragments tested also had no effect on the migration of L929 cells in the Boyden Chamber assay. Pectin stimulated the proliferation and migration of L929 cells, whereas, ORC 1 and heparin both suppressed proliferation (25% - 45% inhibition) of these cells but stimulated their migration. When injected subcutaneously into Polyvinyl alcohol sponges in the rat wound model at concentrations of 10 and 50J.1g/ml, heparin brought about an increased presence of granulation tissue in the wound after 10 days and 7 days respectively. These results indicate that structurally similar polysaccharides can have profoundly different effects on cell proliferation and migration, and thus have potential therapeutic use in guiding cell movement in wound healing.

No description available.

名古屋大学博士学位論文 学位の種類 : 博士(医学)(課程) 学位授与年月日:平成25年3月25日 原真由氏の博士論文として提出された

Hypothesis: Trimethoprim promotes wound healing, decreases lesion counts and improves quality of life of recessive dystrophic epidermolysis bullosa (RDEB) patients. Objectives: Assess feasibility of conducting a large randomized clinical trial. Determine efficacy of trimethoprim in healing of chronic wounds, decreasing lesion counts and improving quality of life of RDEB patients. Methods: Prospective, randomized, double-blinded, placebo-controlled, cross-over pilot study. Results: Ten patients enrolled in the trial, 7 completed both study periods. Despite showing that all patients improved on trimethoprim and that there was a 41% difference in affected area percent change favoring trimethoprim, the cross-over analysis did not show a significant difference between the drug and placebo (p=0.08). Secondary outcome measures did not achieve statistical significance. Limitations: Small sample size, large variation in wound size and unaccounted confounders. Conclusions: Although patients experienced improvement while on trimethoprim, no statistical significant change was showed when compared to placebo.

Potential targeting of impaired wounds resulting from hyperglycemia using mesenchymal stem cells is a promising approach. We hypothesized that when administered to dermal wounds in hyperglycemic subjects, neonatal mesenchymal stem cells (MSCs) would be more effective than adult mesenchymal cells in accelerating healing. We examined the in vitro impact of various glucose conditions on proliferation and senescence of human umbilical cord perivascular cells (HUCPVCs) and adult bone marrow MSCs (hBM-MSCs). We also investigated the healing potential of both cells in dermal wounds of streptozotocin-induced NOD-scid-gamma (NSG) mice utilizing planimetry and histomorphometry. HUCPVCs showed higher proliferation under normal and hyperglycemic conditions and lower senescence under all conditions compared to hBM-MSCs. Wound closure was better in treated wounds compared to untreated wounds. Disease tolerance varied among mice which affected healing. HUCPVCs still holds a potential over adult MSCs for impaired wounds; yet more studies are needed to recognize their bona fide capacity.