The main objectives of this dissertation was: 1) to review the available evidence with respect to the period prevalence of pre-race upper respiratory tract infections (the week before a distance running event) in distance runners, the relationship between exercise and infections, and the possible health consequences of participating in sport whilst suffering from an acute infective illness; 2) to document the period prevalence of runners with an acute illness in the 7-day period prior to an endurance race; 3) to determine the period prevalence of runners who "fail" the "neck check", and would be advised not to participate in the race, 4) to determine the incidence of runners with an acute illness, and who received educational information and guidelines, and who then not start the race, 5) to determine the incidence of runners with an acute illness who chose to start the race, but do not finish the race, and 6) to determine the incidence of runners with an acute illness who chose to start the race, but develop medical complications during the race.

M.Sc. (Med.), Faculty of Health Sciences, University of the Witwatersrand, 2009

Les implants dentaires sont maintenant largement utilisés pour remplacer les dents manquantes chez les patients partiellement ou complètement édentés. Plusieurs facteurs de risque qui peuvent contribuer à des maladies péri-implantaires sont désormais identifiés tels que la mauvaise hygiène buccodentaire ou des habitudes tabagiques. Cependant, il n'y a toujours pas de consensus sur plusieurs facteurs systémiques qui peuvent interférer avec l'obtention ou le maintien d'une ostéointégration de l'implant. L'objectif de cette étude était d'examiner systématiquement la survie des implants et la perte osseuse marginale radiographique autour de ces implants chez les patients souffrant de différentes maladies ou conditions osseuses. Une recherche bibliographique de différentes bases de données a été réalisée en incluant des études publiées entre janvier 1990 et décembre 2019. La revue systématique et la méta-analyse ont été effectuées conformément aux lignes directrices recommandées par la directive du "Preferred Reporting Items for Systematic Review and Meta-Analyses". Suivant les critères d'inclusion et d'exclusion établis, cette revue systématique a retenu six articles sur le diabète avec 661 implants au total et deux études sur des patients ostéoporotiques avec 274 implants au total. Dans la population diabétique, les paramètres péri-implantaires étaient généralement pires en particulier lorsque leur niveau glycémique n'était pas contrôlé. Quatre des études ont été incluses dans la méta-analyse. Il y avait moins de perte osseuse chez la population non diabétique (différence moyenne 0,46 mm; intervalle de confiance 95% (0,06-0,86), z=2,28, p=0,02) par rapport aux patients ayant un diabète non contrôlé. Il n'y avait aucune différence dans les taux de survie des implants entre les deux populations à l'étude. Chez les patients ostéoporotiques, il n'y avait pas de différence de survie des implants ou de perte osseuse marginale par rapport aux patients sains. Cette revue systématique et méta-analyse ont démontré que les patients diabétiques non contrôlés doivent être traités avec prudence mais aucune conclusion n'a pu être tirée sur d'autres maladies et conditions osseuses. Des études à long terme bien menées sont nécessaires afin d'établir des lignes directrices pour traiter les patients ayant des maladies systémiques de façon adéquate. / Dental implants are now widely used to replace missing teeth in partially or fully edentulous patients. Several risk factors associated to peri-implant diseases are now recognized such as poor oral health or smoking habits. However there is no consensus on several systemic factors that may interfere with gaining or maintaining osteointegration. The objective of this study was to systematically review the survival of implants and radiographic marginal bone loss around those implants in patients that have bone diseases or conditions that affect bone metabolism. A literature search of different databases was conducted for studies published between January 1990 and December 2019. The systematic review and meta-analysis were done according to the guidelines recommended by the "Preferred Reporting Items for Systematic Review and Meta-Analyses statement". Following the established inclusion and exclusion criteria, we selected six published articles on diabetic patients with 661 implants in total and two published studies on osteoporotic patients with 274 implants in total. In the diabetic population, peri-implant parameters were generally worse particularly when their diabetes was not controlled. Four of the studies were included in the meta-analysis. There was less bone loss in the non-diabetic population (mean difference 0.46 mm; 95% confidence interval (0.06-0.86), z=2.28, p=0.02) as compared to patients that have poorly controlled diabetes. There was no difference in implant survival rates in the two studied populations. As for osteoporotic patients there was no difference in implant survival or marginal bone loss when compared to healthy patients. This systematic review and meta-analysis showed that uncontrolled diabetic patients need to be treated with caution. No conclusions were drawn on any other bone diseases and conditions. More long-term studies are needed to establish guidelines to provide better patient care in the presence of systemic disease.

Plusieurs études investiguent la péri-implantite, mais aucun consensus à ce jour n’est encore établi. But : Cette étude vise à éclaircir notre compréhension sur la péri-implantite et à en déterminer la prévalence et les facteurs de causalités liés à sa présence dans une cohorte de patients de la clinique de parodontie de l’Université Laval. Méthode : Une étude transversale a été réalisée sur 86 patients et 258 implants placés entre 1999 et 2014. La cueillette des données de chaque patient a été effectuée à l’aide de leurs dossiers médicaux et dentaires, un questionnaire préalablement établi ainsi qu’un examen de rappel clinique et radiologique. Résultats : La prévalence de patients et d’implants avec une péri-implantite a été 15,11 % et 6,44 % respectivement. Les facteurs statistiquement significatifs pour la péri-implantite se sont révélés être l’état dentaire et les prothèses articulaires. Conclusion : Nos résultats ont démontrent une prévalence pour la péri-implantite inférieure à celles retrouvées dans la littérature. Cela confirme que nos protocoles ont bien été implémentés et exécutés. / Several studies have investigated peri-implantitis complication, but no consensus to date has yet been established. Purpose: The study aims to clarify our understanding of peri-implantitis and to determine the prevalence and causal factors associated with its presence in a cohort of patients at Laval University’s periodontics clinic. Methods: A cross-sectional study was carried out on 86 patients and 258 implants placed between 1999 and 2014. Each patient’s data was completed using their medical and dental records, a pre-established questionnaire, and a clinical and radiological recall examination. Results: The prevalence of patients and implants with peri-implantitis was 15.11% and 6.44%, respectively. The statistically significant factors for peri-implantitis were found to be the dental condition and joint prostheses. Conclusion: Our results show a lower peri-implantitis prevalence than those found in the literature. This confirms that our protocols are well implemented and executed.

No

Tang, Xiaolin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 132-144). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

二型糖尿病和肥胖症業已成為威脅人類健康的世界性難題。二型糖尿病和肥胖症與心血管疾病的發生發展緊密相關，這是患者致死致殘的最常見原因。因此，揭示糖尿病和肥胖導致心血管疾病的細胞機制，發展更有效而低副作用的治療策略是目前極需研究的課題。本論文主要對以下幾個方面進行了研究探討，第一，在糖尿病和肥胖小鼠中，內質網應激和氧化應激在其內皮功能障礙中的病理學作用；第二，內質網應激能否成為干預靶點；第三，運動鍛鍊改善內皮功能和降低血管炎症，是如何通過限制內質網應激及調節其他糖尿病和肥胖相關的細胞機制來實現的。 / 論文的第一部份揭示了內質網應激及氧化應激在糖尿病內皮功能障礙中所起的關鍵作用。離體組織培養實驗結果顯示，內質網應激誘導劑衣霉素可以顯著地損傷乙酰膽鹼誘導的血管內皮依賴性舒張（EDR），並增加活性氧自由基（ROS）的產量。用內質網應激緩和劑四苯基乙酸（4-PBA）和牛磺酸共軛熊脫氧膽酸（TUDCA）處理血管，可以修復衣霉素和其他風險因子，如高糖，骨形成蛋白4（BMP4）等損傷的血管舒張。類似，ROS清除劑可以減輕衣霉素誘導的EDR損傷。此外，衣霉素可以抑制元代培養的小鼠主動脈內皮細胞的一氧化氮（NO）產量，而這種抑制效果可以被4-PBA和TUDCA逆轉。對db/db糖尿病小鼠用PBA和TUDCA進行慢性口服治療後，內皮功能得到明顯改善，上調的內質網應激得以恢復正常，同時一氧化氮合酶（eNOS）的活性顯著提高，這些結果支持了內質網應激在糖尿病中的病理學作用，提供了內質網應激緩和劑治療糖尿病內皮障礙的的可能性。 / 論文的第二部份研究了過氧化物酶体增殖物活化受體δ(PPARδ) 在抗糖尿病藥物二甲雙胍誘導的腺苷單磷酸活化蛋白激酶（AMPK）激活對血管保護中的作用，及其與內質網應激的聯繫。實驗結果顯示，在食誘導肥胖（DIO）的PPARδ野生型小鼠中，慢性口服二甲雙胍治療可以改善EDR，抑制內質網應激的標誌性蛋白表達和ROS的過高產量，並提高主動脈eNOS的磷酸化水平。這些血管保護效應在PPARδ敲除的DIO小鼠中消失。體內實驗的結果在體外得以證實，二甲雙胍改善EDRs，提高PPARδ的表達和eNOS的磷酸化，抑制小鼠主動脈內質網應激標誌物的表達，並提高了小鼠內皮細胞的NO產量。所有這些效應都可以被PPARδ的抑製劑GSK0660阻斷。這些結果闡明了在AMPK激活劑作用條件下，PPARδ在降低內質網應激，抑制氧化應激和提高NO產量中的顯著作用。 / 生活方式的優化，例如日常的體育鍛鍊，一直以來就被視為改善血管和代謝的重要方式，但這其中的機制並不完全清楚。因此，論文的第三部份主要探索了運動對血管的改善作用。實驗結果顯示，對db/db糖尿病小鼠進行跑步訓練后，導管動脈和阻滯動脈的EDR得到明顯改善，過高內質網應激，炎性反應和氧化應激，以及內皮細胞中被抑制的AMPK和eNOS都會恢復正常。此外，運動對血管功能的保護作用在DIO的PPARδ 野生型小鼠中可以實現。但是，在DIO的PPARδ敲除小鼠中，增加的內質網應激及其氧化應激卻不因運動鍛鍊而降低。這些結果揭示了糖尿病和肥胖中，PPARδ作為保護血管功能的運動誘導信號的關鍵效應器。 / 總而言之，論文的研究提供了一系列新穎的機制和證據，支持了AMPK依賴的PPARδ激活和內質網應激緩解作為潛在的治療策略用於抵抗糖尿病血管病變。這些新發現同樣也為二甲雙胍在臨床上的使用提供了有益的信息，同時為代謝綜合徵病人通過增強運動機能來有效地保護血管功能提供了有效參考。 / Type 2 diabetes mellitus and obesity increasingly represent a global health problem and are associated with the development and progression of cardiovascular disease which is one of leading causes of mortality and disability worldwide. Hence, there is an urgent need to delineate clearer cellular mechanisms of cardiovascular outcomes in diabetes and obesity, and to develop more effective therapeutic strategies with fewer side effects. The present study aimed at examining (1) the pathological role of endoplasmic reticulum (ER) stress and reactive oxygen species (ROS) over-production in the induction of endothelial dysfunction in diabetic and obese mice, (2) whether ER stress is a therapeutic target, and (3) whether physical exercise improves endothelial function and reduces vascular inflammation through limiting ER stress and other regulatory cellular mechanisms involved in diabetes and obesity. / The first set of experiments show that ER stress and associated oxidative stress serves as a key contributor to endothelial dysfunction in diabetes. The results from ex vivo tissue culture with aortas show that ER stress inducer tunicamycin markedly impairs acetylcholine-induced endothelium-dependent relaxations (EDR) in company with elevated ROS production. Treatment with ER stress alleviators 4-phenyl butyric acid (PBA) and taurine-conjugated ursodeoxycholic acid (TUDCA) restore the impaired relaxations in arteries treated with tunicamycin and other risk factors, high glucose and bone morphogenic protein 4 (BMP4). Likewise, ROS scavengers attenuate tunicamycin-induced impairment of EDR. In addition, tunicamycin reduces nitric oxide (NO) production in primary culture mouse aortic endothelial cells; and its inhibitory effect on NO bioavailability was reversed by co-treatment with PBA and TUDCA. Chronic daily oral administration of PBA and TUDCA rescues endothelial function, normalizes the upregulation of ER stress and oxidative stress, and enhances endothelial NO synthase (eNOS) activity in the aortas from db/db mice, thus supporting a pathological role of ER stress as well as the therapeutic potential of ER stress alleviators in preserving endothelial function with diabetes. / The second series of experiments examined the role of peroxisome proliferator-activated receptor delta (PPARδ) in vascular benefits of activation of AMP-activated protein kinase (AMPK) induced by the anti-diabetic drug metformin in connection with ER stress. Chronic oral metformin treatment improves EDR, inhibits the expression of ER stress markers and ROS over-production, and increases phosphorylation of eNOS in aortas from diet-induced obese (DIO) PPARδ wild-type (WT) mice. These beneficial effects were absent in DIO PPARδ knockout (KO) mice. The benefits of chronic metformin administration are supported by the in vitro data showing that metformin ameliorates EDR, increases PPARδ expression and eNOS phorsphorylation, and suppresses the expression of ER stress markers in mouse aortas; and enhances NO production in mouse endothelial cells. All these effects were blocked by PPARδ antagonist GSK0660. The present results support a significant role of PPARδ in contributing to the reduced ER stress and oxidative stress, and to the increased NO production upon stimulation with AMPK activator. / Lifestyle modification such as regular physical exercise has long been appreciated for its vascular and metabolic benefits though the underlying mechanisms which are not fully understood. The third group of experiments explored the vascular benefits of exercise. Physical running exercise improves EDR in conduit and resistance arteries from db/db mice by normalizing the increased expression or levels of ER stress, inflammation, and oxidative stress, as well as by restoring the diminished activities of AMPK and eNOS in endothelial cells. Vascular benefits were also observed in DIO PPARδ WT mice. However, increased ER stress and associated oxidative stress cannot be reduced by exercise in DIO PPARδ KO mice. These results elucidate that PPARδ serves as a key mediator of exercise-induced signaling that mediate the vasoprotective effect of exercise in diabetes and obesity. / To summarize, the present investigation has provided several lines of novel mechanistic evidence in support for the positive role of AMPK-dependent PPARδ activation and ER stress alleviation as potentially therapeutic target to combat against diabetic vasculopathy. The new findings of the present study also provide useful information in support of the clinical utilization of metformin and recommendation of increased physical activity as another effective measure to preserve vascular function in patients with metabolic syndrome. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Cheang, Wai San. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 131-152). / Abstracts also in Chinese.

published_or_final_version / Medicine / Doctoral / Doctor of Philosophy

Mode of access: World Wide Web. / Thesis (Ph. D.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 116-154). / Electronic reproduction. / Also available by subscription via World Wide Web / xvii, 157 leaves, bound ill. 29 cm

Considerable interest has been expressed regarding the issue of recovery of language following head injury in childhood. The two questions most frequently addressed are: 1) Do children recover linguistic abilities faster and better than adults after suffering a head Injury? 2) Is the linguistic disorder, if evident, mainly syntactic or lexical in nature? We have examined 8 children from 6;10-17; 0 who suffered traumatic head injury and who are in varying stages of recovery. Each child has been matched with a normal child of the same age. Despite reports of complete recovery from childhood aphasia, our results indicate persistent word finding problems, with otherwise normal language abilities. There was no correlation between severity of deficit and age at injury or length of coma. / Medicine, Faculty of / Audiology and Speech Sciences, School of / Graduate