Acute phase proteins (APP) are ideal biomarkers for inflammation due to their stability, relative ease of assay and apparent relation between their concentration and the extent of the insult to tissue. C-reactive protein (CRP) is a positive major APP in dogs and can be used as a predictive marker for risk of disease and to monitor the response to treatment. Increased concentrations in certain diseases are associated with poor outcome. This cross-sectional, observational study of 75 dogs naturally infected with Babesia rossi, a cause of virulent canine babesiosis, was designed to examine the association of CRP concentration at admission and the magnitude of CRP change 24 hours after admission with outcome. Dogs were excluded if there was evidence of concurrent inflammatory diseases at the time of admission, infection with subtypes other than B. rossi, concurrent Ehrlichia canis infections or euthanasia for reasons other than poor prognosis. Diagnosis was confirmed by polymerase chain reaction and reverse line blot. CRP concentrations were determined by an automated human CRP Turbidometric Immunoassay (TIA), previously validated for use in dogs (Bayer CRP TIA, Newbury, UK), on serum samples collected by jugular venipuncture on admission, prior to any therapy, and thereafter daily until discharge or death. There was no significant difference in admission CRP concentration between survivors (n = 57; median = 97.4 mg/l; mean ± SD = 107.5 ± 49.5), and non-survivors (n = 11; median = 101.4 mg/l; mean ± SD = 122.1 ± 64.6) (p = 0.39). After elimination of non-significant predictors, a multiple exact logistic regression model for predicting mortality contained glucose and CRP. Mortality was associated with decreased glucose levels (p = 0.0002) and increased CRP levels (p = 0.045) on admission. Multiple regression analysis failed to show a significant relationship between admission CRP concentration and number of days of hospitalization in the survivors, adjusting for age and sex (p = 0.65). No significance was found in the relationship between the magnitude of change in CRP concentration 24 hours after admission, and the number of days of hospitalization in survivors, (p = 0.34). Using an admission CRP concentration cut-off of 60 mg/l, survival proportions between the two groups were no different (p = 0.34) and when applied to the group of dogs that survived, it was not associated with length of hospitalization (p = 0.25). In corroboration with previous reports glucose was identified as a major prognostic marker for mortality, but additionally the pro-inflammatory marker CRP was identified as a significant co-prognosticator. Copyright / Dissertation (MMedVet)--University of Pretoria, 2009. / Companion Animal Clinical Studies / unrestricted

Le rétrécissement aortique calcifié (RAC) est une maladie calcifiante de la valve aortique caractérisée par un remodelage fibro-calcique lentement progressif des feuillets valvulaires, et par un remodelage du ventricule gauche (VG). Il n’existe à ce jour aucun traitement pharmacologique capable de prévenir la maladie, et le seul traitement consiste en un remplacement valvulaire chirurgical ou percutané. Les objectifs de cette thèse étaient d’identifier des déterminants de la progression du RAC et du remodelage VG, d’étudier une nouvelle modalité d’évaluation de la sévérité du RAC, et d’analyser par une approche expérimentale les mécanismes initiateurs de la calcification valvulaire aortique. Les résultats de ce travail peuvent être résumés comme suit : - Le taux plasmatique de galectine-3 n’était pas associé au degré de sévérité du RAC ou au statut fonctionnel des patients. La galectine-3 n’avait pas de valeur pronostique sur la survenue d'événements liés au RAC. Les résultats observés sont en défaveur de l'utilisation de ce biomarqueur au cours de la prise en charge des patients ayant un RAC asymptomatique. - Dans une cohorte prospective de patients ayant un RAC au moins minime, le volume de graisse épicardique était indépendamment associé à un remodelage péjoratif du VG. Ce résultat suggère que la graisse épicardique pourrait être un déterminant du remodelage pathologique du VG via une interaction locale. - L’utilisation de l’imagerie de fusion a entrainé une augmentation du taux de discordance entre les paramètres de sévérité du RAC. Ce résultat était plus marqué chez les patients ayant une valve aortique bicuspide. Au regard de la classification et des seuils définissant actuellement la sévérité du RAC, et du fait de leur valeur pronostique bien démontrée, les résultats de cette étude sont en défaveur de l'utilisation de l’imagerie de fusion pour évaluer la sévérité du RAC. - L’accumulation dans le feuillet valvulaire aortique d’érythrocytes sénescents, suite à la survenue de lésions endothéliales non cicatrisées, constitue une situation délétère favorisant la différenciation des cellules valvulaires interstitielles vers un phénotype ostéoblastique et in fine le dépôt de calcium conduisant au RAC. La physiopathologie d’initiation des calcifications valvulaires et de progression du RAC est complexe et multifactorielle. La découverte de cibles thérapeutiques potentielles et l’optimisation de la prise en charge des patients ayant un RAC nécessite de combiner des études cliniques pour identifier les déterminants de la progression et de la réponse myocardique au cours du RAC, et une approche fondamentale pour caractériser les mécanismes impliqués dans la maladie. / Calcific aortic stenosis (AS) is characterized by a slowly progressive fibrocalcific remodeling of aortic valve leaflets, and by a left ventricular (LV) remodeling. There is currently no effective medical treatment capable of preventing disease progression, and the only treatment is surgical or percutaneous valve replacement. The objectives of this thesis were to identify determinants of AS progression and LV remodeling, to study a new modality of evaluation of AS severity, and to analyze through an experimental approach the initiating mechanisms of valve calcification. The results of this work can be summarized as follows: - The plasmatic level of galectin-3 was not associated with the degree of AS severity or the functional status of patients. Galectin-3 had no prognostic value for the occurrence of AS-related events. The results observed are not in favor of the use of this biomarker for the management of patients with asymptomatic AS. - In a prospective cohort of patients with at least mild AS, epicardial fat volume was independently associated with an adverse remodeling of the LV. This result suggests that epicardial fat may be a determinant of pathological LV remodeling through a local interaction. - The use of fusion imaging increased the rate of discordant AS severity parameters. This result was more pronounced in patients with a bicuspid aortic valve. Considering current classification and thresholds defining AS severity, and their well-proven prognostic value, the results of this study do not favor the use of fusion imaging to assess AS severity. - The accumulation of senescent erythrocytes in aortic valve leaflets, consecutive to unhealed endothelial injury, is a noxious condition that promotes the differentiation of valvular interstitial cells towards an osteoblastic phenotype and favor calcium deposition leading to AS. The pathophysiology of initiation of valvular calcification and AS progression is complex and multifactorial. The discovery of potential therapeutic targets and the optimization of the management of patients with AS require the combination of clinical studies to identify the determinants of AS progression and myocardial response, and a fundamental approach to characterize mechanisms involved in the disease.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18162号 / 医博第3882号 / 新制||医||1003(附属図書館) / 31020 / 京都大学大学院医学研究科医学専攻 / (主査)教授 福原 俊一, 教授 佐藤 俊哉, 教授 坂田 隆造 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第12888号 / 論医博第2088号 / 新制||医||1007(附属図書館) / 31642 / (主査)教授 小泉 昭夫, 教授 平家 俊男, 教授 福山 秀直 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13063号 / 論医博第2121号 / 新制||医||1018(附属図書館) / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 髙橋 良輔, 教授 福原 俊一, 教授 中山 健夫 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20252号 / 医博第4211号 / 新制||医||1020(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 三森 経世, 教授 伊達 洋至, 教授 竹内 理 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 新制・課程博士 / 博士(医学) / 甲第24802号 / 医博第4994号 / 新制||医||1067(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 石見 拓, 教授 近藤 尚己, 教授 湊谷 謙司 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 新制・課程博士 / 博士(社会健康医学) / 甲第24807号 / 社医博第131号 / 新制||社医||12(附属図書館) / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 中山 健夫, 教授 山本 洋介, 教授 髙橋 良輔 / 学位規則第4条第1項該当 / Doctor of Public Health / Kyoto University / DFAM

Background: Most patients with high-risk melanomas develop metastasis within the first few years after diagnosis. However, late recurrence of melanoma is seen in patients that metastasize more than 10 years after the primary diagnosis; a metastasis after 15 years is considered an ultra-late recurrence. It is critical to better understand the clinical and biological characteristics of this subset of melanoma patients in order to offer an individual treatment plan and prevent metastasis. Methods: We retrospectively analyzed melanoma patients with recurrence ≥10 years after a primary diagnosis documented between 1993 and 2012 at the skin cancer center of the University Medical Center Leipzig, Germany. We conducted a comprehensive review of the literature and compared the results with our data. Available archived primary melanoma tissue was investigated with a seven-marker immunohistochemical signature (immunoprint®) previously validated to reliably identify high-risk patients within stages IB-III. Results: Out of 36 analyzed patients, a third metastasized ultra-late (≥15 years). The mean age at initial diagnosis was 51 years, with women being diagnosed comparatively younger than men. The largest proportion of patients with late recurrence had primary melanomas located on the trunk. The immunoprint® signature of the available primary melanomas allowed the accurate prediction of a high risk. However, it is difficult to draw a definitive conclusion from the small number of cases that could be analyzed with immunoprint® (n = 2) in this study. Apart from the primary tumor characteristics, the laboratory values at time of metastasis, comorbidities and outcome are also shown. Conclusion: Late and ultra-late recurrent melanomas seem not to differ from melanomas in general, apart from a distinctly higher proportion of lower leg localizations in ultra-late recurrent melanomas. The immunoprint® signature may help to identify high-risk primary tumors at the time of initial diagnosis. However, apart from the risk profile of the primary tumor, it seems that individual immune surveillance can control residual tumor cells for more than a decade. Advanced age and increasing comorbidities may contribute to a disturbed immunological balance.

Stroke is an acute neurological deficit that results from abnormal blood flow to the brain. The term stroke encompasses two primary subgroups: hemorrhagic stroke that is due to extravasation of blood and ischemic stroke that is due to vessel obstruction. Determining stroke type and underlying etiology is a crucial step in patient management as it influences treatment strategies. Currently diagnosis of stroke relies on clinical examination and neuroimaging, but there is a lack of rapid diagnostic and prognostic testing. Using microarray technology we identified a novel association between elevated peripheral blood expression of MCEMP1 and stroke. We have also shown that MCEMP1 discriminates between primary stroke types and predicts one-month post-stroke prognosis. Since genetic mechanisms underlying stroke remain incompletely understood we next conducted a global gene network analysis. Network analysis identified four large groups of co-expressed genes associated with ischemic stroke. NLRC4, CKLF, and HS.546375 were the most interconnected genes within unique modules and each was also independently associated with ischemic stroke. We show that multi-gene models have greater discriminative capacity for stroke and stroke prognosis, than single gene models. In addition to stroke biomarkers we also identified biomarkers of atrial fibrillation (AF), a known risk factor of stroke. Currently our understanding of the molecular mechanisms underlying AF remains incompletely understood. Thus we conducted whole blood expression profiling in patients with persistent AF before and after successful electrical cardioversion, a procedure that aims to restore sinus rhythm to the heart. We identified elevated expression of SLC25A20 and PDK4 during AF as compared with sinus rhythm. Furthermore we show that SLC25A20, PDK4 and NT-proBNP have incremental utility to discriminate AF from sinus rhythm. Taken together, the thesis implicates new genes with stroke and AF, and also indicates that whole blood RNA biomarkers may have clinical utility. / Thesis / Doctor of Philosophy (PhD)