Yes / Purpose.: The aim of this work was to develop an in vitro cornea model to study the effect of proinflammatory cytokines on wound healing. Methods.: Initial studies investigated how to maintain the ex vivo models for up to 4 weeks without loss of epithelium. To study the effect of cytokines, corneas were cultured with the interleukins IL-17A, IL-22, or a combination of IL-17A and IL-22, or lipopolysaccharide (LPS). The effect of IL-17A on wound healing was then examined. Results.: With static culture conditions, organ cultures deteriorated within 2 weeks. With gentle rocking of media over the corneas and carbon dioxide perfusion, the ex vivo models survived for up to 4 weeks without loss of epithelium. The cytokine that caused the most damage to the cornea was IL-17A. Under static conditions, wound healing of the central corneal epithelium occurred within 9 days, but only a single-layered epithelium formed whether the cornea was exposed to IL-17A or not. With rocking of media gently over the corneas, a multilayered epithelium was achieved 9 days after wounding. In the presence of IL-17A, however, there was no wound healing evident. Characterization of the cells showed that wherever epithelium was present, both differentiated cells and highly proliferative cells were present. Conclusions.: We propose that introducing rocking to extend the effective working life of this model and the introduction of IL-17A to this model to induce aspects of inflammation extend its usefulness to study the effects of agents that influence corneal regeneration under normal and inflamed conditions.

Yes / The total energy consumption of many Reverse Osmosis (RO) plants has continuously improved as a result of manufacturing highly impermeable membranes in addition to implementing energy recovery devices. The total energy consumption of the RO process contributes significantly to the total cost of water treatment. Therefore any way of keeping the energy consumption to a minimum is highly desirable but continues to be a real challenge in practice. Potential areas to explore for achieving this include the possibility of optimising the module design parameters and/or the associated operating parameters. This research focuses on this precise aim by evaluating the impact of the design characteristics of membrane length, width, and feed channel height on the total energy consumption for two selected pilot-plant RO process configurations for the removal of chlorophenol from wastewater. The proposed two configurations, with and without an energy recovery device (ERD), consist of four cylindrical pressure vessels connected in series and stuffed with spiral wound membranes. A detailed steady-state model developed earlier by the authors is used here to study such impact via repetitive simulation. The results achieved confirm that the overall energy consumption can be reduced by actually increasing the membrane width with a simultaneous reduction of membrane length at constant membrane area and module volume. Energy savings of more than 60% and 54% have been achieved for the two configurations with and without ERD respectively using process optimization. The energy savings are significantly higher compared to other available similar studies from the literature.

No / 482 people with leg ulcers were identified among those receiving health care in Bradford, UK. Of these wounds 195 (40.4%) were venous leg ulcers. Typically the people who experienced these wounds were elderly Caucasian females however a sub-group of younger males of Asian descent were seen to experience ulcers involving neuropathy. The leg ulcers were typically small in size although 33 people had wounds over 25 cm2 in surface area. The leg ulcers tended to persist with many present for at least 1 year with 4 wounds active for over 5 years. 205 people had experienced previous episodes of leg ulcer occurrence. Of the leg ulcers encountered 18.0% (n = 87) were infected and where wounds were swabbed for their microbial burden MRSA was identified in 8.5% of cases. Use of Doppler ultrasound to assess the aetiology of the wound had been performed in 66.4% of cases and where wounds remained undiagnosed (n = 69) only 8 had been Doppler assessed. While 75% of all venous leg ulcers received compression 48 people with venous leg ulcers did not have compression applied to their wound.

No

No description available.

Wei, Fangyuan. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 182-211). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

HA (Hyaluronan, hyaluronic acid) is a predominant component of the extracellular matrix and plays diverse roles in the process of wound healing. The major significance of the biological functions of HA in wound healing arise from early studies showing that rich and prolonged existence of HA is associated with the fetal scarless wound healing. It has been hypothesized that adult wound healing can be modulated by the application of exogenous HA to make the process of wound repair more like regeneration. / In this thesis, the effects of molecular weight and concentration of HA on the biological behavior of human fibroblasts and keratinocytes have been investigated in both monolayer and 3D culture models. In addition, the mechanism for the HA-induced biological effects has also been investigated. Previous laboratory studies have primarily focused on individual cell type, but in wound healing in vivo there is considerable interaction between the keratinocytes and fibroblasts. The role of HA in keratinocyte-fibroblast interactions is not clear, so an organotypical culture model was used to investigate the keratinocyte differentiation and stratification and basement membrane formation with and without fibroblasts to explore the effect of HA on keratinocyte-fibroblast interactions. / The experimental data suggest that exogenous application of HA modulates the process of wound healing so that it becomes more like regeneration by regulating the biological functions of human keratinocytes and fibroblasts, including their interaction. By further understanding the HA-induced cell biological phenomena and involved mechanisms new approaches for wound care may be revealed. / The skin is the largest organ in the body. It consists of an outer layer, the epidermis supported by a connective tissue matrix, the dermis. The keratinocyte and fibroblast are the major cell types in the epidermis and dermis respectively. When the skin is damaged, the body will active a cascade of mechanisms to restore the tissue integrity. If the damaged tissue is limited to the epidermis, it will be restored by the process of regeneration. Regeneration involves the replacement of injured tissue by new tissue which has both form and function identical to the original tissue. If the defect involves the dermis, healing is achieved by repair which results in permanent scar formation. Wound healing is an extremely complex biological process which involves several overlapping steps; inflammation, granulation tissue formation and remodeling which are coordinated by various cell types, growth factors, cytokines and extracellular matrix components including hyaluronan. / Whilst there have been many studies looking at the effect of HA on different cell types using varying molecular parameters, concentrations and sources of HA, the result are often contradictory. Even the endogenous or exogenous application of HA have been reported to have opposite effects on cell behavior. / Gu, Hua. / Adviser: Andrew Bard. / Source: Dissertation Abstracts International, Volume: 71-01, Section: B, page: 0216. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 116-135). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Introduction: Endoscopic sinus surgery (ESS) is at present the gold standard therapeutic modality for chronic rhinosinusitis (CRS) resistant to medical therapy. Whilst results from ESS for CRS are generally good, postoperative bleeding and impaired wound healing with adhesion formation remains a concern. Due to patient discomfort and the detrimental effects on wound healing caused by most packing materials, many surgeons no longer routinely use nasal packing. Surgeons have in the past sought agents which would provide post-operative haemostasis without detrimentally affecting wound healing. Antifibrinolytics have been available for many years, however, their topical application has only been explored in the last few years. Recently different forms of chitosan have separately shown significant promise as powerful haemostatic and anti-adhesion agents. The aim of this thesis was to explore the progressive understanding of the interaction between haemostasis and wound healing with possible development of a novel agent. Methods: The first step to scientifically assess bleeding after sinus surgery was to develop a standardised method of video endoscopy and grading the surgical field during ESS. This was done as a multinational collaborative trial. Once this assessment tool was validated a randomised controlled trial evaluating the effect of two antifibrinolytics (epsilon aminocaproic acid and tranexamic acid) was conducted. Further evaluation was then conducted on other possible hemostatic and antiadhesion substances. This included various combinations of a novel chitosan gel. These gels were trialled in vitro to determine their effect on human nasal fibroblasts derived from CRS patients. Fibroblast adhesion and proliferation as well as closure of standardised wounds were studied. The most promising of these gels was then used in an in vivo sheep model. Once effectiveness of the chitosan-dextran gel was shown in the laboratory, this was evaluated against a number of currently available hemostatic and anti-adhesion substances in a standardised model of wound healing in sheep with CRS. This model had been previously extensively validated in our department. Full thickness mucosal injuries were created on the lateral nasal wall and ethmoids of twenty sheep and recombinant tissue factor (rTF), SprayGel or Chitosan-Dextran derivative gel applied topically in a randomized fashion. Adhesion formation and severity as well as microscopic wound healing and ciliary function were analysed at day 28, 56, 84 and 112 post initial surgery. A further sheep study was conducted applying chitosan dextran gel to standardised mucosal injuries and comparing its effect on the control of bleeding to control. Bleeding time and grade were recorded and wound healing monitored via serial videoendoscopy over two weeks and objectively measured. Results: a) Assessment of the bleeding scales showed that inter and intra observer reliability for both scales tested were significantly improved by employing a standardized video-endoscopy technique. The Wormald scale proved to be more reliable and sensitive to changes in the most common surgical fields encountered in ESS. b) Tranexamic acid showed a modest but clinically significant improvement in the surgical field at 2, 4 and 6 minutes after application. Epsilon aminocaproic acid did not effectively improve the surgical field. c) Nasal fibroblast adhesion and proliferation were significantly impaired with dextran and chitosan. The most effective ratio that delayed but did not prevent wound closure were 5 % chitosan: 5 % dextran gel. d) In a standardised sheep model of mucosal wound healing the chitosan gel significantly decreased lateral nasal wall and ethmoidal adhesions at all time points. The chitosan group had a significantly greater percentage of re-epithelialisation and reciliation than control and rTF. In addition the mean cilial grade in the chitosan group was significantly better than control. e) The chitosan dextran gel was significantly more haemostatic at 2,4, and 6 minutes after injury with no significant difference noted in wound healing. Conclusions: Standardised methods of videoendoscopy and grading the surgical field in ESS are valuable tools for further research. Tranexamic acid significantly improved the surgical field to a moderate degree in ESS compared to control. Chitosan gel is a promising new powerful haemostatic bio-polymer which has a mild inhibitory effect on fibroblast attachment and proliferation. This may partially explain the significant improvement in microscopic wound healing and reduction in adhesion formation seen in a sheep model of chronic sinusitis. Future work evaluating this gel in the setting of a human trial is currently underway. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1375402 / Thesis (Ph.D.) -- University of Adelaide, School of Medicine, 2009

Embryonic stem cells (ESCs) can differentiate into all somatic cells, and as such, are a promising cell source for therapeutic applications. In vitro, ESCs spontaneously differentiate via the aggregation of cells into embryoid bodies (EBs), which recapitulate aspects of early embryogenesis and harbor a unique reservoir of cues critical for tissue formation and morphogenesis. Embryonic healing responses employ similar intrinsic machinery used for tissue development, and these morphogenic cues may be captured within the EB microenvironment. Recent studies have shown that when injected into injury or defect models in vivo, ESCs synthesize and secrete extracellular factors that ultimately contribute to repair, suggesting that these molecules may be as important for regenerative therapies as functional differentiation of the cells. The overall objective of this project was to develop novel acellular matrices derived from differentiating ESCs undergoing morphogenesis. The central hypothesis was that embryonic matrices contain complex mixtures of extracellular factors that, when isolated, retain bioactivity and enhance wound healing in an adult environment. The overall objective was accomplished by: (1) investigating the production of extracellular matrix (ECM) by differentiating ESCs as a function of differentiation time; (2) assessing the ability of solvents to efficiently decellularize EBs; and (3) evaluating the healing response elicited by acellular matrices derived from EBs in a murine dermal wound healing model. Endogenous ECM synthesis by EBs varied with time and was associated with specific differentiation events. Novel techniques were developed to effectively remove cell components from EBs in order to extract complex, bioactive acellular matrices. EB-derived acellular matrices significantly enhanced the healing of excisional dermal wounds in mice, indicating the potency of extracellular factors synthesized by ESCs. All together, these studies demonstrate that acellular matrices derived from ESCs retain morphogenic factors capable of influencing tissue repair. In addition, this work lays the foundation for future studies to further examine the functional role of endogenous matrix molecules on ESC differentiation and to evaluate the utility of a stem cell-derived matrix for a variety of regenerative medicine applications.

Introduction: Endoscopic sinus surgery (ESS) is at present the gold standard therapeutic modality for chronic rhinosinusitis (CRS) resistant to medical therapy. Whilst results from ESS for CRS are generally good, postoperative bleeding and impaired wound healing with adhesion formation remains a concern. Due to patient discomfort and the detrimental effects on wound healing caused by most packing materials, many surgeons no longer routinely use nasal packing. Surgeons have in the past sought agents which would provide post-operative haemostasis without detrimentally affecting wound healing. Antifibrinolytics have been available for many years, however, their topical application has only been explored in the last few years. Recently different forms of chitosan have separately shown significant promise as powerful haemostatic and anti-adhesion agents. The aim of this thesis was to explore the progressive understanding of the interaction between haemostasis and wound healing with possible development of a novel agent. Methods: The first step to scientifically assess bleeding after sinus surgery was to develop a standardised method of video endoscopy and grading the surgical field during ESS. This was done as a multinational collaborative trial. Once this assessment tool was validated a randomised controlled trial evaluating the effect of two antifibrinolytics (epsilon aminocaproic acid and tranexamic acid) was conducted. Further evaluation was then conducted on other possible hemostatic and antiadhesion substances. This included various combinations of a novel chitosan gel. These gels were trialled in vitro to determine their effect on human nasal fibroblasts derived from CRS patients. Fibroblast adhesion and proliferation as well as closure of standardised wounds were studied. The most promising of these gels was then used in an in vivo sheep model. Once effectiveness of the chitosan-dextran gel was shown in the laboratory, this was evaluated against a number of currently available hemostatic and anti-adhesion substances in a standardised model of wound healing in sheep with CRS. This model had been previously extensively validated in our department. Full thickness mucosal injuries were created on the lateral nasal wall and ethmoids of twenty sheep and recombinant tissue factor (rTF), SprayGel or Chitosan-Dextran derivative gel applied topically in a randomized fashion. Adhesion formation and severity as well as microscopic wound healing and ciliary function were analysed at day 28, 56, 84 and 112 post initial surgery. A further sheep study was conducted applying chitosan dextran gel to standardised mucosal injuries and comparing its effect on the control of bleeding to control. Bleeding time and grade were recorded and wound healing monitored via serial videoendoscopy over two weeks and objectively measured. Results: a) Assessment of the bleeding scales showed that inter and intra observer reliability for both scales tested were significantly improved by employing a standardized video-endoscopy technique. The Wormald scale proved to be more reliable and sensitive to changes in the most common surgical fields encountered in ESS. b) Tranexamic acid showed a modest but clinically significant improvement in the surgical field at 2, 4 and 6 minutes after application. Epsilon aminocaproic acid did not effectively improve the surgical field. c) Nasal fibroblast adhesion and proliferation were significantly impaired with dextran and chitosan. The most effective ratio that delayed but did not prevent wound closure were 5 % chitosan: 5 % dextran gel. d) In a standardised sheep model of mucosal wound healing the chitosan gel significantly decreased lateral nasal wall and ethmoidal adhesions at all time points. The chitosan group had a significantly greater percentage of re-epithelialisation and reciliation than control and rTF. In addition the mean cilial grade in the chitosan group was significantly better than control. e) The chitosan dextran gel was significantly more haemostatic at 2,4, and 6 minutes after injury with no significant difference noted in wound healing. Conclusions: Standardised methods of videoendoscopy and grading the surgical field in ESS are valuable tools for further research. Tranexamic acid significantly improved the surgical field to a moderate degree in ESS compared to control. Chitosan gel is a promising new powerful haemostatic bio-polymer which has a mild inhibitory effect on fibroblast attachment and proliferation. This may partially explain the significant improvement in microscopic wound healing and reduction in adhesion formation seen in a sheep model of chronic sinusitis. Future work evaluating this gel in the setting of a human trial is currently underway. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1375402 / Thesis (Ph.D.) -- University of Adelaide, School of Medicine, 2009