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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
381

Cysteinyl leukotriene receptor 2 activation mediates post-myocardial ischemia/reperfusion injury inflammatory processes

Ni, NATHAN 26 September 2013 (has links)
Myocardial infarction (MI) is primarily caused by blockade of the coronary circulation, resulting in ischemic insult. The only available remedy is reperfusion, which induces oxidative stress and activates inflammatory responses at the site of injury. Cysteinyl leukotrienes (cysLTs) are potent pro-inflammatory mediators that exert their effects through two classical receptors: cysLT receptor 1 (CysLT1R) and cysLT receptor 2 (CysLT2R), the latter of which is prevalent in the heart and circulatory system and has been implicated in cardiovascular disease. However, although endothelial CysLT2R overexpression exacerbates MI damage and induces vascular hyperpermeability, understanding of CysLT2R activation-induced mechanisms is poor, as isolating CysLT2R-specific effects has proven difficult due to a lack of appropriate pharmacological agents. We investigate herein the role of CysLT2R activation in myocardial ischemia/reperfusion injury. We have characterized a novel CysLT2R-selective antagonist BayCysLT2 in both in vitro and in vivo systems, and establish that CysLT2R-selective antagonism attenuates exacerbated MI injury, adhesion molecule gene regulation, and myocardial neutrophil presence observed in CysLT2R overexpressing (EC) mice. We also examined effects of CysLT2R antagonism in long-term cardiac remodeling post-myocardial infarction, and found that blockade of CysLT2R post-reperfusion, regardless of whether CysLT2R is overexpressed or not, elicits a mild pathological cardiac hypertrophic response despite mitigating infarction damage to the apical ventricular wall. Finally, we created a novel mouse model (EC/KO) that expresses CysLT2R predominantly in vascular endothelium in order to identify tissue-specific mechanisms of CysLT2R activation. Surprisingly, MI injury was attenuated in EC/KO mice, indicating that both endothelial and non-endothelial CysLT2R expression subsets have roles in mediating infarction injury. Indeed, EC/KO mice demonstrated hyperpermeability in cremaster venules only when leukotrienes are applied, in contrast to EC mice. In addition, endothelial CysLT2R activation facilitates leukocyte transmigration, whereas non-endothelial CysLT2Rs regulate basal rolling leukocyte flux in microvasculature. Although much work remains to be done, the characterization of a CysLT2R-selective antagonist provides a vital tool for CysLT2R research moving forward, and our investigation of CysLT2R activation reveal the existence of a complicated and multi-faceted pathway resulting in activation of pro-inflammatory mechanisms. / Thesis (Ph.D, Physiology) -- Queen's University, 2013-09-26 10:29:03.466
382

Blood markers for the diagnosis and prognosis of stroke

Whiteley, William Nichol January 2011 (has links)
Many blood markers have been associated with stroke. I set out to determine whether blood markers can be applied to: (i) improve the accuracy of the clinical diagnosis of stroke or TIA, and/or (ii) improve the prediction of poor outcome in patients who are still symptomatic at the time of admission with stroke or TIA. I systematically reviewed the existing literature on the diagnostic performance of a range of blood markers measured soon after stroke onset, to inform the choice of markers for my subsequent prospective studies in this thesis. Many studies had deficiencies in their design, which may have explained the apparently – and perhaps spuriously - impressive diagnostic performance of several markers. In the light of these data I was able to improve the design of my own studies and suggest how future studies of diagnostic markers could be improved. In order to define an appropriate comparator test for assessing the diagnostic accuracy of blood markers, I first examined the performance of emergency room nurses and doctors. I assessed the accuracy of their diagnosis of TIA or stroke (‘acute cerebrovascular disease’) in patients presenting with symptoms of suspected stroke, and compared them with a number of stroke diagnostic scales. In the 405 patients recruited to the study, the sensitivity of emergency department staff was 77% and specificity 58%. Each stroke diagnostic scale had a slightly better sensitivity, though worse specificity, than an emergency department clinician. I decided to use the diagnosis by an emergency department clinician of ‘probable or definite acute cerebrovascular disease’ as the best clinical performance reference standard. In blood taken from the same cohort of 405 patients, accredited research laboratories measured markers of inflammation, thrombosis, thrombolysis, cardiac strain and cerebral damage. Tissue plasminogen activator and loge N-terminal pro brain natriuretic peptide were associated positively with a diagnosis of acute cerebrovascular disease, though each marker did not add diagnostic value to the diagnosis of an emergency department doctor or nurse. I systematically reviewed the literature examining the association between the levels of blood markers with poor outcome (i.e. death or dependency) after stroke. I found that although almost all markers studied had a positive association with poor outcome, there were methodological problems with many studies, chiefly small sample size, publication bias or within study reporting biases, and lack of adjustment for important confounders such as age or stroke severity. With data from the Edinburgh Stroke Study, I examined the association between circulating markers of the inflammatory response (white cell count, interleukin-6, Creactive protein and fibrinogen) and poor outcome after stroke. After adjustment for age, whether the patient lived alone, was independent of activities of daily living, was orientated, able to lift both arms and able to walk, I found that higher levels of interleukin-6, white cell count and glucose were associated with poor outcome. The relevant test of a biological marker is not its predictive ability alone, but whether, when added to a validated predictive model based on clinical variables, it improves the prediction of outcome. No individual marker improved the prediction of poor outcome when added to a validated prognostic model based on clinical variables alone. From my cohort of 405 patients with suspected stroke 285 patients had a confirmed diagnosis. Follow up of these 285 patients with confirmed acute cerebrovascular disease showed that, after adjustment for neurological impairment and age, only interleukin-6 and N-terminal pro brain natriuretic peptide were significantly associated with death or disability at 3 months. Neither marker improved the predictions of a model to predict poor outcome based on clinical variables alone. To examine the relationship between circulating markers of the inflammatory response and recurrent stroke, myocardial infarction, and vascular death (‘recurrent vascular events’), again I used data from the Edinburgh Stroke Study. After adjustment for clinical predictors (age, prior MI, stroke, or TIA and AF) I found that higher levels of interleukin-6, C-reactive protein and fibrinogen remained significantly associated with an increased risk of recurrent vascular events. However, the relationship with deaths from all causes was somewhat stronger for each marker, perhaps suggesting that higher marker levels were associated with debility rather than vascular events per se. In conclusion, I found no marker measured could improve on the diagnostic accuracy of an emergency department clinician for acute cerebrovascular disease, nor improve the prediction of poor outcome by a prognostic model based upon clinical variables. The work of this thesis does not support the routine use of blood markers as an aid to the diagnosis of, or the prediction of outcome of, acute stroke.
383

Expression of Semaphorin 3E in Asthma and its role in Allergic Airway Disease

Movassagh, Hesamaldin 01 February 2016 (has links)
Asthma is a chronic condition characterized by variable airflow obstruction, bronchial hyper-responsiveness, airway inflammation and remodeling. In spite of tremendous advances, the regulatory mechanisms controlling these pathological features have not yet been completely addressed. From an immunological perspective, type 2 inflammation and eosinophilic infiltration are the most striking hallmarks of asthma. At physiological level, structural changes such as increase in smooth muscle mass take the center stage which is usually associated with clinical measures of asthma. There might be some regulatory mediators capable of tuning airway inflammation and remodeling under homeostatic conditions but abrogated in asthmatic conditions. Semaphorin 3E (Sema3E) is an axon guidance molecule that is ubiquitously expressed and plays diverse roles in structural and inflammatory cells such as regulation of cell migration, proliferation and angiogenesis. However, its role in clinical and experimental asthma remains unclear. In this thesis, I have set out to uncover the expression and function of Sema3E in allergic asthma. It is generally hypothesized that Sema3E is down-regulated in allergic asthma which orchestrates the function of inflammatory (dendritic cells and neutrophils) and structural (airway smooth muscle) cells. Replenishment of Sema3E, which is suppressed under asthmatic conditions, could confer protection against allergic asthma by modulation of cellular functions. I began by comparing the expression of Sema3E between allergic asthmatics and healthy subjects. A remarkable down-regulation of Sema3E under asthmatic patients was observed which was further confirmed in a mouse model of the disease. Decreased expression of Sema3E was specifically demonstrated on bronchial epithelial cells obtained from asthmatic patients at both mRNA and protein levels. To address the function of Sema3E in allergic asthma in vivo, I extended my studies to mouse models of the disease and demonstrated that Sema3e gene deletion results in exacerbated allergic asthma pathology induced by allergen exposure. To investigate the translational relevance of my findings, I performed treatment of an asthmatic mouse model with exogenous Sema3E in which its intranasal administration attenuated airway inflammation, remodeling and hyper-responsiveness. The mechanism underlying Sema3E’s role in pathogenesis of allergic asthma was extensively studied indicating a crucial role of this mediator in modulation of dendritic cells and neutrophils functions. Our data demonstrated that both dendritic cells and neutrophils express the Sema3E high affinity receptor, PlexinD1, which makes them responsive to Sema3E treatment. Then, I studied expression and function of PlexinD1 on human airway smooth muscle (ASM) cells. I found that PlexinD1 surface expression was reduced on ASM cells from asthmatic patients. Treatment of ASM cells with Sema3E inhibited their proliferation and migration as the characteristic feature of airway remodeling. Suppression of Rac1 GTPase activity and phosphorylation of Akt/PI3K and ERK/MAPK were found as signaling mechanisms underlying Sema3E’s inhibitory effects. Together, these findings show that Sema3E thereby appears as a novel regulatory mediator, upstream of pro-allergic events, suggestive of a new approach to attenuate allergic asthma deficits. / May 2016
384

Modulation de la signalisation du récepteur du facteur d'activation plaquettaire par SOCS3

Rollin, Simon January 2009 (has links)
Le facteur d'activation plaquettaire (PAF) est un puissant médiateur pro-inflammatoire impliqué dans des processus physiologiques et pathologiques.Le PAF exerce ses effets suite à la liaison à son récepteur, le récepteur du PAF (PAFR), qui est un récepteur à sept domaines transmembranaires et couplé aux protéines G (RCPG). La signalisation du PAFR est en partie médiée par les protéines G et implique principalement des sous-unités G[indice inférieur [alpha]i] et G[indice inférieur [alpha]q] dans plusieurs types cellulaires.Le PAFR peut également activer des effecteurs variés : des canaux ioniques, des phospholipases (PLA[indice inférieur 2], PLC, PLD), ainsi que plusieurs kinases (PKC, PI3K et MAPK). Nous avons récemment démontré que le PAFR peut activer de façon indépendante des protéines G la voie des Janus kinase (JAK) et des Signal Transducers and Activators of Transcription (STAT). JAK2, TYK2 et STAT1, 2, 3 et 5 sont ainsi activés dans la lignée cellulaire myéloïde humaine MonoMac1. Les SOCS sont une famille de protéines qui régulent négativement la signalisation des cytokines et qui ont récemment été démontrés comme impliqués dans la signalisation de certains RCPG dont le CXCR4 (récepteur de chimiokine 4 de la famille des C-X-C) et l'AT1 (récepteur de l'angiotensine II). Une stimulation au PAF induit de manière transcriptionnelle l'accumulation de l'ARNm de la protéine suppressors of cytokine signalling 3 (SOCS3) dans les monocytes humains et la lignée cellulaire MonoMac1, mais ne l'induit pas dans les cellules endothéliales de veines de cordons ombilicaux humain (HUVEC). En plus d'une augmentation de l'ARNm de SOCS3, une augmentation de la protéine SOCS3 est également observée suivant une stimulation au PAF. Premièrement, nous voulions déterminer l'importance de SOCS3 dans la signalisation du PAFR à l'aide de différentes lignées cellulaires (HEK293, COS7, MonoMac1) et diverses techniques de biologie cellulaire. Ensuite, nous désirions évaluer l'impact des différents domaines de SOCS3 dans ces fonctions par des approches de biologie moléculaire. Finalement, nous avons évalué le/s rôle/s de SOCS3 sur différents aspects fonctionnels pro-inflammatoires du PAF (Voies signalisation, adhésion cellulaires, etc.). Nous démontrons dans la présente thèse que SOCS3 module la signalisation du PAFR en plus de présenter certains aspects moléculaires entourant la relation entre le PAFR, TYK2 et SOCS3. Les présents travaux démontrent que SOCS3 peut être recruté de façon transitoire à la seconde boucle intracellulaire et la queue cytoplasmique du PAFR. Son domaine kinase inhibitory region (KIR) semble être requis pour le recrutement induit au PAFR, alors que son domaine SOCS box semble être impliqué dans le recrutement basal. Suivant une stimulation au PAF, SOCS3 est phosphorylé sur un/des résidus tyrosine. Cette modification est sous le contrôle essentiel de TYK2, alors que son mutant K930I (kinase inactive) ne le fait pas. SOCS3 joue un rôle très important dans la modulation des voies de signalisation du PAFR ainsi que sur certains effets biologiques de celui-ci. Ces actions se révèlent être également très spécifiques : SOCS3 ne module pas la voie de G[indice inférieur [alpha]q] (IP3 ), mais module la migration et également l'adhésion cellulaire induite par le PAF. SOCS3 ne module pas la phosphorylation des STAT 1, 3 et 5 induite par le PAF, mais module négativement la voie de TYK2 (activation du promoteur du PAFR) et la phosphorylation des STAT 1, 3 et 5 induite par l'OSM. SOCS3 ne module pas la voie des JNK MAPK, prolonge la voie des ERK MAPK et module négativement l'activation précoce de la voie de p38 MAPK. Enfin, SOCS3 joue un rôle de modulation négative dans la transcription induite par le PAF des promoteurs du PAFR, de l'IL-6 et de l'IL-8. En conclusion, cette thèse propose de nouveaux mécanismes par lesquels SOCS3 module certains aspects de la signalisation et effets biologiques du PAF et de son PAFR. Comme le PAF est impliqué dans plusieurs phénomènes à caractères inflammatoires, le travail présenté ici a porté son attention sur plusieurs aspects pro-inflammatoires du PAF plutôt que sur une pathologie en particulier, ce qui permettra de mieux comprendre divers aspects liant le PAFR, la kinase TYK2 et SOCS3.
385

Reprogramming of Myeloid Compartments Supporting Tissue Repair During Dss-Induced Colitis Recovery

Tremblay, Alexandra 06 January 2017 (has links)
Myeloid-derived suppressor cells (MDSC), emerging during tumor growth or chronic inflammation play a critical role in regulating T cell function. However, mechanisms governing the generation of these cells remain unclear, and need to be further defined. Using a DSS-induced colitis and recovery model, we characterized the dynamic changes within myeloid compartments and the emergence of MDSC during active and resolution phases of inflammation. We show that the immature myeloid compartment expands in bone marrow (BM) specifically at the resolution phase of inflammation during colitis transition to recovery. Additionally, we found enhanced levels of IL-17 in the serum of colitis mice tightly correlates with expansion of the IMC compartment, and is likely the factor responsible for expansion of these cells. Our study also determined that the expanded population of myeloid cells underwent a functional reprogramming event. In particular, two major functional changes occurred when colitic mice were allowed to recover: 1) CD11b+Gr-1+ myeloid cells in bone marrow and spleen acquired T cell suppressive functions, and 2) acquired the ability to enter into circulation from BM, confirming previously reported characteristics of MDSC. Additionally, we determined that acquired migratory capability in the low density myeloid cells isolated from resolution time points was due to enhanced surface expression of chemokine receptor CXCR2. Furthermore, we determined that after mobilization of MDSC from the bone marrow, these cells collected in the T cell-rich spleens, where they effectively functioned to suppress T cell proliferation. Through these acquired functions, our study determines a protective role for MDSC during the recovery phase of post-acute inflammation during persistent DSS-induced colitis.
386

Cortical Astrocytes Acutely Exposed to the Monomethylarsonous Acid (MMA(III)) Show Increased Pro-inflammatory Cytokines Gene Expression that is Consistent with APP and BACE-1: Over-expression.

Escudero-Lourdes, C, Uresti-Rivera, E E, Oliva-González, C, Torres-Ramos, M A, Aguirre-Bañuelos, P, Gandolfi, A J 10 1900 (has links)
Long-term exposure to inorganic arsenic (iAs) through drinking water has been associated with cognitive impairment in children and adults; however, the related pathogenic mechanisms have not been completely described. Increased or chronic inflammation in the brain is linked to impaired cognition and neurodegeneration; iAs induces strong inflammatory responses in several cells, but this effect has been poorly evaluated in central nervous system (CNS) cells. Because astrocytes are the most abundant cells in the CNS and play a critical role in brain homeostasis, including regulation of the inflammatory response, any functional impairment in them can be deleterious for the brain. We propose that iAs could induce cognitive impairment through inflammatory response activation in astrocytes. In the present work, rat cortical astrocytes were acutely exposed in vitro to the monomethylated metabolite of iAs (MMA(III)), which accumulates in glial cells without compromising cell viability. MMA(III) LD50 in astrocytes was 10.52 μM, however, exposure to sub-toxic MMA(III) concentrations (50-1000 nM) significantly increased IL-1β, IL-6, TNF-α, COX-2, and MIF-1 gene expression. These effects were consistent with amyloid precursor protein (APP) and β-secretase (BACE-1) increased gene expression, mainly for those MMA(III) concentrations that also induced TNF-α over-expression. Other effects of MMA(III) on cortical astrocytes included increased proliferative and metabolic activity. All tested MMA(III) concentrations led to an inhibition of intracellular lactate dehydrogenase (LDH) activity. Results suggest that MMA(III) induces important metabolic and functional changes in astrocytes that may affect brain homeostasis and that inflammation may play a major role in cognitive impairment-related pathogenicity in As-exposed populations.
387

Impact de l'inflammation à bas bruit associée à l'obésité sur l'établissement des troubles de l'humeur et de la cognition

Dinel, Anne-Laure 19 December 2008 (has links)
De nombreuses études menées chez l’homme ont montré que l’obésité est associée à un état inflammatoire chronique caractérisé par une augmentation de la sécrétion de nombreuses molécules dont la leptine et des cytokines inflammatoires comme le TNF-a et l’IL-6 (Clement et al., 2004). Des données récentes suggèrent que cette inflammation périphérique pourrait également présenter une composante au niveau cérébral se caractérisant notamment par une augmentation de l’expression de différentes cytokines inflammatoires (IL-6, TNF-a, IL-1ß…) et de l’activation de leurs voies de signalisation intracellulaire (augmentation de l’activité c-Jun-N-terminal kinase et de NFkB)(De Souza et al., 2005). De plus, l’intensité de la situation inflammatoire semble être liée au degré d’obésité. Ainsi, il est possible de distinguer différentes situations d’obésité : une obésité modérée qui ne s’accompagne pas forcément de pathologies comorbides et une obésité morbide associée à différents types de complications comme des maladies cardio-vasculaires, de l’hypertension artérielle ou un diabète de type 2. L’obésité s’accompagne également d’une forte prévalence de troubles de l’humeur (anxiété, dépression) et de la cognition. Notre laboratoire a été un des pionniers dans l’étude de l’expression et de l’action des cytokines au niveau central et de leurs conséquences, tant comportementales que neurobiologiques. Cette relation entre système de l'immunité innée et cerveau a particulièrement été étudiée dans le cadre du comportement de maladie regroupant un ensemble de symptômes non spécifiques (fièvre, activations neuroendocriniennes, anorexie, anhédonie, repli sur soi, perte d’intérêt pour l’environnement…) observés chez les individus malades et pouvant être reproduits chez l’animal en réponse à l’injection d’un inducteur de cytokines tel que le lipopolysaccharide (LPS)(Dantzer, 2001). Dans le cas d’une exposition prolongée ou non régulée de l’activation du réseau de cytokines, le comportement de maladie peut laisser place à de véritables troubles de l’humeur et de la cognition associés à une chute des taux circulants de tryptophane, un acide aminé essentiel servant de précurseur et de facteur limitant à la synthèse de sérotonine. Il a été montré que l'indoléamine 2,3-dioxygénase (IDO), une enzyme dégradant le tryptophane en réponse aux cytokines (Lestage et al., 2002; Moreau et al., 2005) est impliquée dans l’induction des symptômes de type dépressif observés notamment suite à production soutenue de cytokines et que cette action serait dépendante du catabolisme du tryptophane via la voie de la kynurenine (O'Connor et al., 2008). L’activation de l’IDO en situation inflammatoire aboutit à la production de dérivés neurotoxiques (3-OH-kynurénine, acide quinolinique) se comportant comme des agonistes des récepteurs glutamatergiques de type NMDA (Taylor and Feng, 1991), au dépend de la production de sérotonine. Ainsi, l’activation de l’IDO par les cytokines pourrait jouer un rôle dans l’apparition de troubles cognitifs associés aux états inflammatoires via l’altération de la neurotransmission sérotoninergique et/ou glutamatergique. Ces mêmes mécanismes pourraient également sous-tendre le développement des troubles de l’humeur et de la cognition couramment observés chez les personnes obèses. L’ensemble des études réalisées dans ce travail de thèse a donc eu pour objectif général de déterminer chez la souris si l’inflammation chronique à bas bruit qui est associée à un état d’obésité entraînait le développement de troubles de l’humeur et de la cognition [...]. / Severe obesity is associated with a low grade inflammation characterized by an increased release of inflammatory markers like cytokines and leptin. It has been suggested that some of these mediators of inflammation could also be found in the brain, as manifested by the increased hypothalamic expression of inflammatory cytokines (IL-6, TNF-a, IL-1) and the activation of their intracellular pathways. Moreover, the intensity of the inflammation state seems to increase with the degree of obesity. Morbid obesity, which is accompanied by different comorbid pathologies like cardiovascular disease, hypertension, type 2 diabetes and a high prevalence of mood (anxiety, depression) and cognitive disorders, is clearly associated with peripheral inflammation. Such an association is less clear in the case of a moderate obesity which is not systematically associated with comorbid pathologies. It is clearly established that during an infection brain actions of cytokines that are released as a result of the innate immune system activation induce development of sickness behaviour. In the case of a prolonged and/or unregulated activation of the cytokine network, sickness behaviour that includes non-specific symptoms such as behavioral alterations, fever and neuroendocrine activation can lead to the development of mood and cognitive disorders. Moreover, such a development is associated with a drastic drop of circulating levels of tryptophan, the essential amino acid acting as limiting factor of the serotonin synthesis. It has been proposed that these alterations could be at least partially explained by cytokine-induced peripheral and/or central activation of the indoleamine 2,3-dioxygenase (IDO), a tryptophan-catabolizing enzyme that is potently induced in monocytes, macrophages and brain microglia by cytokines. IDO activation can result in the lowering of the bioavailability of tryptophan for 5-HT synthesis and the increase of neurotoxic derivates (3-OH-kynurenine, quinolinic acid). Both consequences of cytokine-induced IDO activation may play a role in the development of the cognitive and mood disorders associated with obesity. The present study aimed therefore at studying in mice the relationship between inflammation and development of mood and cognitive disorders associated with obesity. This study was performed in two different but complementary experimental conditions reproducing 1) a moderate obesity devoid of marked pathological complications (a model of diet induced obesity) and 2) a morbid obesity associated with comorbid pathologies like type 2 diabetes (db/db mice). Our results showed that: 1) The degree of obesity is correlated with the intensity of the alterations affecting innate immune system activation. 2) Obesity exacerbates the innate immune system activation as manifested by the increase of peripheral and central cytokine production, and related neurochemical, neuroendocrine and behavioral alterations. 3) The inflammation-related alterations induced by obesity are associated with impairment of cognitive abilities and emotional reactivity, as well as development of anxiety-like symptoms, although differences in their respective time-course of appearance seem to exist. Taken together, these findings showed the key role of the inflammation associated with obesity in its related mood and cognitive disorders. This work provides therefore a first important step towards the identification of new pharmacological and/or nutritional strategies aimed at ameliorating life quality of obese subjects and preventing development of related comorbidities.
388

Explorations non-invasives de l’inflammation alvéolaire et de ses conséquences sur les échanges gazeux au cours de la pneumopathie interstitielle diffuse associée à la sclérodermie systémique / Non-invasive explorations of alveolar inflammation and its consequences on gas exchange in systemic sclerosis-associated interstitial lung disease

Le Dong, Nhat Nam 22 November 2011 (has links)
Pas de résumé français / Pas de résumé anglais
389

Vulvar vestibulitis syndrome : an ultrastructural and epidemiological investigation

Sargeant, Penelope January 1996 (has links)
Vulvar Vestibulitis Syndrome (VVS) is a chronic inflammatory condition affecting the vestibular epithelium of the vulva, which has been estimated to affect 15% of the female population (Goetsch, 1991). Many studies have attempted unsuccessfully, to elucidate the cause of this condition, and few advancesh ave beenm adet owards the understandingo f the associatedin flammatory responseT. he initial, and principal aim of this investigation was to characterise normal vestibular epithelium using electron microscopy. The ultrastructural characteristics of normal vestibular epithelium were compared with closely related epithelia, and with vestibular epithelia from VVS patients. Other aims included an investigation of the epidemiological characteristics of VVS; an assessmenot f vulvar sensitivity over several months, and an evaluation of ketoconazole as a non-invasive treatment for VVS. Transmission electron microscopy, confirmed that vestibular epithelium was non-keratinised, and closely resembled oral and vaginal mucosae. Intermediate cells were predominant, characterised by pale staining cytokeratin filaments and glycogen deposits. Leukocytes were present in small numbers. Using SEM, superficial cells were characterised by an interlacing network of rounded microridges. By comparison, vestibular epithelium from VVS patients demonstrated the presence of numerous, intensely staining, apoptotic-like cells. These cells were associated with membrane bound cytoplasmic lobules and leukocytes of varying types. A similar ultrastructural appearance was observed in post-treatment biopsies. However, apoptotic-like cells appeared heavily vacuolated, and the number of cytoplasmic bodies present was increased. Mature plasma cells, NK-like cells and macrophages were common in the dermis. Leukocyte counts, demonstrated a significantly greater number of leukocytes in the VVS biopsies compared with the controls, however, there was no statistical difference in the number of leukocytes in pre and post-treatment samples. The presence of apoptotic-like cells accompanied by a significant inflammatory cell infiltrate, may suggest a cell signalling defect, resulting in the pain associatedw ith VVS. Treatment with ketoconazolec ream was found to have very little effect on either the number of leukocytes or the frequency of apoptotic-like cells as quantified using image analysis. The epidemiological characteristics of VVS patients were investigated using a structured questionnaire interview. All of the VVS patients interviewed fulfilled the diagnostic criteria established by Friedrich (1987), and epidemiological findings were generally consistent with previous epidemiological reports. Unique to this study, HPV infections were rare, however recurrent Candida infections and cystitis were commonly reported. The 'Vulvar Algesiometer', was designed and developed in Plymouth, to assist diagnosis and assessmenot f VVS patients. Using this equipment, VVS patients demonstrate heightened vestibular sensitivity when compared with control patients. The utilisation of a pain measuring device the 'Vulvar Algesiometer', in accordance with the questionnaire and ultrastructural investigation has formed a novel and balanced approach to the study of VVS. This study has demonstrated several distinct features of VVS which have not previously been described, features which may be important in elucidating the cause of this condition. These features centre around the presence of apoptotic-like cells and associated cytoplasmic bodies which have not previously been described in association with VVS.
390

A study of magnesium intake and its possible relation to inflammation

Hanzon, Johanna January 2016 (has links)
The study was initiated to examine magnesium intake, supplementation and their relation to inflammation. Magnesium is the second most abundant extracellular ion following potassium. Outside the cell, magnesium can be found in bone tissue, cardiac muscle tissue, other tissues and in the blood. Magnesium form compounds which operate in several essential metabolic processes in the body. Magnesium deficiency may have an impact on insulin resistance and endothelial dysfunction, which may result in an increased level of inflammation. Increased inflammation over a longer period has been seen to increase the risk of common lifestyle induced diseases such as diabetes type II and coronary heart diseases. The study of magnesium and its influence on inflammation is thereby becoming important and interesting for all societies and in their effort to find solutions to maintain and increase the well-being of its individuals. The study is a literature study based on searches made in One Search and Pub Med databases. A total of ten studies were included, five for magnesium intake and five for supplementation. The majority of the studies showed a significant correlation between increased magnesium intake, dietary and supplementary, with decreased levels of inflammatory biomarkers and hints that magnesium might have a role in the inflammation process. What needs to be taken into account is that fiber intake in two studies attenuated magnesium’s inverse relation to inflammation. In addition of a decrease in inflammatory biomarker levels the risk for developing diabetes type II seemed to decrease as well with an increased intake of magnesium in one of the studies. Further studies need to be executed in order to establish the role of magnesium in inflammation and optimal dosage for prevention of metabolic and cardiovascular diseases. / Studien undersöker magnesiumintag och supplementering med magnesium samt dess inverkan på inflammation. Magnesium är den vanligast förekommande jonen intracellulärt efter kalium.  Extracellulärt magnesium förekommer i benvävnad, hjärtmuskelvävnad och i blodet. Magnesium bildar ämnen som medverkar i flera viktiga metabola processer i kroppen. Magnesiumbrist kan ha en inverkan på insulin resistans och endotel dysfunktion som följaktligen skulle kunna resultera i en ökad nivå av inflammation. Ökad inflammation under en längre tid har visat sig öka risken för vanliga livsstilssjukdomar som diabetes typ II och hjärt- och kärlsjukdomar. Forskning om magnesium och dess effekt på inflammation blir därmed viktig och intressant för samhällen i deras strävan att hitta lösningar till att bibehålla och öka välmåendet hos populationen. Studien är en litteraturstudie och är grundad på sökningar via databaserna One Search och Pub Med. Totalt tio studier inkluderades i arbetet, fem som undersökte magnesiumintag och inflammation samt fem som undersökte supplementering av magnesium och inflammation. Majoriteten av studierna visade på en signifikant korrelation mellan ett ökat magnesiumintag, via kosten och kosttillskott, och minskade nivåer av biomarkörer för inflammation. Det antyder att magnesium kan ha en roll i inflammationsprocessen. I de två studier som mätte fiberintaget var relationen mellan magnesiumintag och inflammation försvagad. Utöver en minskning av biomarkörer för inflammation sågs en minskad risk för att utveckla diabetes typ II vid ett ökat magnesiumintag i en av studierna. Fler studier krävs för att fastställa magnesiums betydelse vid inflammation samt den optimala doseringen för prevention av metabola och kardiovaskulära sjukdomar.

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