The long-term success of lung transplantation has been challenged by chronic graft dysfunction, which is manifested as obliterative bronchiolitis (OB). We demonstrated that allograft airway fibrosis is a dynamic process of tissue remodelling, in which cellular and matrix components dynamically change before or after complete obliteration of the airway lumen. This dynamic process was associated with changes in expression and activity of matrix metalloproteinases (MMPs). The early inflammatory phase was associated with MMP-dependent migration of blood-borne fibrocytes, which highly express MMP-9 and MMP-12. ‘Established’ fibrosis was associated with MMP-2 and MMP-14 expressed by myofibroblasts in both human OB lesions and their animal models. In established allograft airway fibrosis, general MMP inhibition resulted in apoptosis of myofibroblasts in vivo and in vitro, while low-doses of MMP-inhibitor treatment induced upregulation of MMP-2, increased collagenolytic activity, and significantly decreased myofibroblasts and collagen. The dynamic process of tissue remodelling in established allograft airway fibrosis was supported by underlying continuous alloimmune responses, in particular, direct T-cell-myofibroblast contact. iii Modulation of tissue remodelling using a low-dose MMP inhibitor in combination with cyclosporine induced partial regression of fibrosis after its establishment. We further demonstrated the mechanism of alloimmune responses unique to the lung. Human and animal studies demonstrated that bronchioles develop de novo lymphoid tissue characterized by formation of high endothelial venules and homing of effector memory T-cells. A following study demonstrated the important role of local immunological memory maintained by the intrapulmonary lymphoid tissue in exerting effector function in allograft rejection. Collectively, the present studies support the hypothesis that tissue remodelling is an important mechanism of allograft airway fibrosis. Regulation of tissue remodelling and underlying tissue injury is important not only to arrest aberrant remodelling of allograft airways but likely to reverse aberrant remodelling and to regenerate normal tissue architecture in airways after lung transplantation.

Chronic inflammation in response to Aß peptide deposits is a pathological hallmark of Alzheimer's disease (AD). The inflammatory environment includes populations of reactive and proliferating microglia and astrocytes and perturbed vasculature. However, the association between activated glial cells and cerebrovascular dysfunction remain largely unknown. This study has used Aß1-42 intrahippocampal injection as an animal model of inflamed AD brain to characterize mechanisms of glial-vasculature responses as a basis for chronic inflammation. Preliminary findings suggested Aß1-42-injected brain demonstrated vascular remodeling including evidence for formation of new blood vessels (angiogenesis). This result led to study of the effects of the anti-angiogenic/anti-inflammatory compound, thalidomide on activated glial cells and perturbations in the vasculature in an Aß1-42 peptide-injected rat model. First, Aß1-42 injection was found to cause perturbations in vasculature including new blood vessel formation and increased BBB leakiness. Second, thalidomide decreased the vascular perturbations and the glial reactivity and conferred neuroprotection. Overall, these results suggest that altered cerebral vasculature is integral to the overall inflammatory response induced by peptide. Experiments then examined the level of parenchymal plasma proteins in brain tissue from AD and nondemented (ND) individuals. AD, but not ND, brain tissue demonstrated high levels of fibrinogen immunoreactivity (ir). Aß1_42 injection into the rat hippocampus increased the level of parenchymal fibrinogen, which was reduced by treatment with the defibrinogenating agent, ancrod. In addition, ancrod also attenuated microglial activation and prevented neuronal injury. Overall, these results demonstrate that extravasation of blood protein and a leaky BBB are important in promoting and amplifying inflammatory responses and causing neuronal damage in inflamed AD brain. Microglial chemotactic responses to VEGF (vascular endothelial growth factor) receptor Flt-1 were next studied. Treatment with a monoclonal antibody to Flt-1 (anti-Flt-1 Ab) in the peptide-injected hippocampus diminished microglial reactivity and provided neuroprotection. Secondly, anti-Flt-1 Ab inhibited the AI3142-induced migration of human microglia. These results suggest critical functional roles for Flt-1 in mediating microglial chemotaxis and inflammatory responses in AD brain. The overall conclusion from my work is that AP deposits induce microglial reactivity which subsequently causes vascular remodeling resulting in an amplified inflammatory microenvironment which is damaging to bystander neurons.

Morphine is one of the most commonly prescribed medications for the relief of prolonged pain. Both basic science and clinical studies indicate that females require 2-3 times more morphine than males to achieve the same analgesic effect. To date, the mechanisms underlying sex differences in opiate responsiveness are unknown. Recent studies suggest that glial cells are potent modulators of morphine-based analgesia, and in particular, decrease the analgesic effect of opiates. Therefore, we tested the hypothesis that the sexually dimorphic effects of morphine were due to sex differences in glial cell activity. Our studies focused on the midbrain periaqueductal gray (PAG) as this region of the brain is critical for the analgesic effects of morphine. Adult male and female Sprague Dawley rats (250g- 400g) were procured from Charles River Laboratories, and were allowed 7 days to acclimate to the new facility. On the day of the experiment, animals received a subcutaneous injection of morphine (5mg/kg) or were handled in a similar manner. Thirty or 60 minutes after injections or handling, animals were perfused with a 4% paraformaldehyde and 2.5% acrolein tissue fixative solution. Brains were removed and stored in 20% sucrose until ready for sectioning. Brains were sectioned at 25mm using a freezing microtome, and immunohistochemical localization of markers for astrocyte glial cell activity was performed. Antibodies to glial fibrillary acidic protein (GFAP) were used to label activated astrocytes. If our hypothesis is correct, then females will have significantly greater density of the astrocyte cell activity marker GFAP as compared with males. Sex differences in PAG glial cell activity may provide the biological bases for the sexually dimorphic effect of morphine. This research may lead to better treatment for females experiencing prolonged chronic or neuropathic pain.

The repetitive ballistic movements in highland dancing, which occur at more than 100 beats/min while the dancers try to reach a maximal vertical height with each jump, could possibly develop chronic injuries similar to ballet and aerobic dance. This study aimed to determine the following: number of injuries/dancer, number of injuries/100 hours of training, the number of chronic injuries compared to acute, anatomical location of the injuries and possible predictors for sustaining an injury in highland dancers. The 76 participants, aged 7 through 22, were from two Saskatoon Dance Schools. The information was collected by retrospective and prospective questionnaires and data analyzed using a Chi-square, analysis of variance and a binary logistic regression. The six-month retrospective survey found a total of 6 dance-related injuries compared to the 42 dance-related injuries in the four-month prospective questionnaire. When analyzing only the injured dancers the CHD (competitive) had 1.62 injuries/dancer, RHD (recreational) had 1.86 injuries/dancer and the Control group (non-highland dancers) had 2.0 injuries/dancer. Significant differences were not found for the number of injuries sustained in these three dance groups (X2 = 0.72, p<0.70). The injury rate per 100 hours of training for only the injured dancers in each group was as follows; CHD 2.59 injuries/100 hours, RHD 4.51 injuries/100 hours and the Control group 4.97 injuries/100 hours. The majority of the chronic versus acute injuries were sustained by the CHD (9 chronic, 8 acute), however they were not statistically different from the RHD (4 chronic, 7 acute) (X2 = 0.738, p<0.05). Most of the injuries occurred to the lower leg, with the knee, shins/calf, ankles and the feet as the major sites. Significant differences were found for these four lower leg sites versus the rest of the body (X2 = 11.20, p<0.05). There were also no differences for the number of lower leg injuries between the CHD and RHD (X2 = 4.605, p<0.05). The three variables associated with an increased risk for sustaining an injury were age, having a previous injury and the onset of menarche.

ABSTRACT Peripheral nerves are most commonly affected by pressure, traction, friction, anoxia or cutting and these injuries can easily cause allodynia of the limbs. Beta-endorphin is an endogenous pain inhibitor. It can produce profound and long-lasting analgesia for patients with intractable pain. Prominent endogenous opioid peptides are modulated by the hypothalamic-pituitary-adrenal axis. The expression of pro-opiomelanocortin (POMC) produces opioid peptides, including the beta-endorphins, other shorter endorphins, adrenocorticotropic hormones (ACTH), and melanocyte-stimulating hormones (MSH). The aim of this study is to evaluate the efficacy of POMC gene therapy for neuropathic pain that is caused by chronic constriction injury (CCI) in a rat model. Experimental painful peripheral neuropathy is induced by CCI of the sciatic nerve which results in allodynia of the hind limb. We used the method of conventional electrical stimulation to quantitatively analyze the efficacy of gene therapy. In addition, two nociceptive tests, including thermal-withdrawal latency and mechanical withdrawal threshold, were also conducted to evaluate the effect of treatment. Adult male Sprague Dawley rats (250-300 g, n = 24) were divided into three groups: (1) the control group (n = 8); (2) the sciatic nerve ligation group that received an injection of adenoviral vectors with green fluorescent protein (Ad-GFP) (n = 8); and (3) the sciatic nerve ligation group that received an injection of adenoviral vectors with POMC gene (Ad-POMC) (n = 8). The electrophysiological studies and nociceptive tests were carried out on day 3 before ligation and days 3, 7 and 14 after ligation. The POMC injection was performed on day 3 after ligation. We measured the amplitude and onset latency of maximal compound muscle action potential (CMAP) in braches of the sciatic nerve (nerves to the gastrocnemius, tibialis anterior), motor nerve conduction velocity, H-reflex and F-wave by electrical stimulation and denervation sign by electromyography (gastrocnemius, tibialis anterior). In addition, the latency of the thermal-withdrawal and threshold of mechanical withdrawal were also recorded. The results showed that prominent thermal-withdrawal latencies and mechanical withdrawal thresholds were elevated in the sciatic nerve ligation group with POMC gene therapy on days 14 and 21 after ligation. It also demonstrated that administrations of POMC gene therapy which produced the beta-endorphins to elevate the pain threshold and reduced the allodynia of the injured limbs. In conventional electrophysiological studies, no significant differences were noted between the Ad-GFP and Ad-POMC groups. The reduction of CMAP amplitude was recorded in rats of the sciatic nerve ligation groups. There was no significant difference in the mean onset latency of CMAP and nerve conduction velocity (NCV) within these three groups, except for the fact that the NCV of the tibial nerve was slowing in the Ad-GFP group on day 14. Electrophysiological analysis was revealed prolonged or absent H-reflex and F-wave in animals of the neuropathy groups by electrical stimulation. Electromyography showed prominent denervation potentials over the sampling muscles in the sciatic nerve ligation groups. In conclusion, POMC gene therapy for neuropathic pain is very efficacious. However, the influence of POMC gene therapy for nerve protection or minimizing the progress of nerve injury will require further investigations.

Thesis (MNutr)--University of Stellenbosch, 2008. / Bibliography. Also available via the Internet.

Thesis (M.S.)--University of Toledo, 2009. / Typescript. "Submitted as partial fulfillment of the requirements for The Master of Science Degree in Pharmaceutical Sciences, Administrative Pharmacy Option." "A thesis entitled"--at head of title. Bibliography: leaves 71-84.

Thesis (M. Med. Sc.)--University of Queensland, 2001. / Includes bibliographical references.

Thesis (M. Med. Sc.)--University of Queensland, 2002. / Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 261-290). Available also in a digital version from Dissertation Abstracts.