• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 64
  • 49
  • 7
  • 4
  • 3
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 139
  • 53
  • 37
  • 23
  • 21
  • 18
  • 16
  • 15
  • 14
  • 14
  • 13
  • 11
  • 10
  • 9
  • 9
  • 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.
61

Papel da insulina no remodelamento na vigência da inflamação pulmonar alérgica em camundongos diabéticos e sadios / Role of insulin on the presence of the remodeling induced by allergic airway inflammation in healthy and diabetic mice

Ferreira, Sabrina de Souza 26 February 2015 (has links)
O diabetes mellitus (DM) e a asma são doenças de elevada incidência mundial. Embora ambas as doenças sejam comuns, há uma correlação negativa entre elas, uma vez que o aparecimento de DM, em pacientes previamente asmáticos, determina uma melhora do quadro asmático, em contrapartida, a insulina agrava a asma. O presente estudo avaliou o papel da insulina na vigência da inflamação alérgica crônica pulmonar em camundongos diabéticos e sadios. Para tanto, foram utilizados camundongos machos, da linhagem BALB/C, tornados diabéticos (aloxana, 50 mg/kg, i.v., 10 dias). Os animais foram sensibilizados com ovalbumina (OVA - 20 µg, e Al(OH)3 -2 mg) 10 dias após a injeção de aloxana e receberam a mesma dose após 12 dias, após 6 dias da última sensibilização os animais foram expostos a nebulização durante 7 dias, com solução de OVA (5 mg/mL), ou salina (SAL). Os animais diabéticos e asmáticos foram separados em dois diferentes grupos, para receberem dois tratamentos distintos de insulina, um tratamento com uma única dose de insulina e outro tratamento com doses consecutivas de insulina, sempre antes dos desafios. Após 24h do último desafio foram feitas as seguintes análises: a) o número de células no fluído de lavado broncoalveolar (LBA), leucograma e a glicemia (monitor de glicose); b) quantificação das concentrações de citocinas (IL1 β, TNF-α, IL-6, IL-4, IL-10, VEGF, TGF-ß) no sobrenadante do fluído de LBA pela técnica de ELISA; c) análise morfológica do tecido pulmonar através de cortes histológicos e coloração em hematoxilina e eosina (H/E) e d) deposição e quantificação de colágeno e muco no tecido pulmonar através de análise morfométrica em cortes histológicos corados com Tricômico de Massom e ácido periódico de Schiff (PAS), respectivamente. Comparados aos controles, camundongos diabéticos apresentaram redução de infiltrado inflamatório (34%) no fluído de LBA e de IL-1β (87%). Ambos os grupos apresentaram leve marcação de colágeno e ausência de muco. Os animais não diabéticos desafiados com OVA, apresentaram um aumento de infiltrado inflamatório (44%) no fluído de LBA com presença de eosinófilos (25%), presença de eosinófilos (34%) no sangue periférico, aumento das concentrações de IL-4 (70%) , deposição de colágeno (72%), e presença de muco, quando comparado ao animal controle. Os animais diabéticos desafiados com OVA apresentaram parâmetros similares aos animais diabéticos que receberam nebulização com SAL. O tratamento dos animais diabéticos com dose única de insulina corrigiu completamente os níveis de celularidade no fluído de LBA, a presença de eosinófilos no sangue periférico, e os níveis de concentrações de IL-4 e IL-1β, mas não corrigiu a deposição de colágeno ao redor das vias aéreas e secreção de muco. Já o tratamento com doses consecutivas corrigiu completamente os níveis de infiltrado inflamatório do LBA, presença de eosinófilos tanto no fluído de LBA como no sangue periférico, os níveis de concentrações de IL-1β, deposição de colágeno e secreção de muco. A concentração de IL-10 não diferiu entre os grupos e as demais citocinas analisadas não foram detectadas no ensaio de enzima-imunoensaio utilizado. Em conjunto estes dados sugerem que a insulina deva regular o remodelamento das vias aéreas em modelo experimental de inflamação alérgica pulmonar em camundongos diabéticos controlando o infiltrado inflamatório, a produção de IL-1β, e consequentemente, a deposição de colágeno e secreção de muco. / Diabetes mellitus (DM) and asthma are diseases of high incidence worldwide. Although both diseases are common, there is a negative correlation between them, since the appearance of DM in asthmatic patients previously determines an improvement in asthma profile, however, insulin exacerbates asthma. This study evaluated the role of insulin in the presence of chronic pulmonary allergic inflammation in diabetic mice and healthy. To this end, male mice were used in BALB / C strain, made diabetic (alloxan, 50 mg / kg, i.v., 10 days). Animals were sensitized with ovalbumin (OVA - 20 mcg, and Al (OH) 3 -2 mg) 10 days after the injection of alloxan and received the same dose at 12 days after 6 days after the last sensitization animals were exposed to nebulized for 7 days with OVA solution (5 mg / ml) or saline (SAL). Diabetics and asthmatic animals were divided in two different groups to receive two different insulin treatment, a treatment with a single dose of treatment with insulin and other insulin consecutive doses of ever before challenge. 24 hours after the last challenge the following analysis: a) the number of cells in the bronchoalveolar lavage (BAL), white blood cell count and blood sugar (glucose monitor); b) quantifying the concentrations of cytokines (IL-1 β, TNF-α, IL-6, IL-4, IL-10, VEGF, TGF-ß) in the BAL supernatant by ELISA; c) morphological analysis of lung tissue by histological sections and stained with hematoxylin and eosin (H / E) and d) deposition and quantification of collagen and mucus in the lung tissue by morphometric analysis of histological sections stained with trichrome of Massom and periodic acid Schiff (PAS), respectively. Compared to controls, diabetic mice showed a reduction of inflammatory infiltrate (34%) in the BAL, IL-4 concentrations (54%) and IL-1β (87%). Both groups showed slight marking of collagen and no mucus. Non-diabetic mice challenged with OVA had an increased inflammatory inflammatory infiltration (44%) in the presence of BAL eosinophils (25%), eosinophils (34%) in peripheral blood, increase in IL-1β (44%), collagen deposition (72%) and presence of mucus compared to control animals. Diabetic animals challenged with OVA showed similar patterns to those diabetic animals given nebulization with SAL. Treatment of diabetic rats with a single dose of insulin completely corrected the cellularity levels in BAL eosinophils in peripheral blood and the levels of IL-1β concentrations, but did not correct deposition of collagen around airways and mucus secretion. Since treatment with consecutive doses completely corrected levels of the inflammatory infiltrate of the BAL eosinophils in both the peripheral blood and BAL, the levels IL-1β concentrations, deposition of collagen and mucus secretion. The IL-10 concentration did not differ between groups and other cytokines analyzed were not detected in the test enzyme-immunoassay used. Together these data suggest that insulin is to regulate airway remodeling in an experimental model of allergic lung inflammation in diabetic mice controlling the inflammatory infiltration, IL-1β, and therefore, deposition of collagen and secretion mucus.
62

Investigation of the role of Mcl-1 and Mer in the regulation of eosinophil apoptosis and efferocytosis

Felton, Jennifer Marie January 2017 (has links)
Regulation of the inflammatory response is essential for the successful resolution of inflammation, and restoration of normal tissue homeostasis. Eosinophils are granulocytic cells of the innate immune system historically considered to be primarily involved in the defence against parasitic infection. Eosinophils are also key effector cells in the allergic inflammatory response, initiation of which is associated with the recruitment and activation of eosinophils culminating in the release of their intracellular granule contents. Eosinophil granules contain a range of cytotoxic proteins (major basic protein, eosinophil cationic protein and eosinophil peroxidase) that act to destroy infectious and parasitic organisms. However, these cytotoxic proteins can also cause damage to surrounding host tissue cells. The resolution of the inflammatory response acts to limit the extent of eosinophil-mediated tissue damage. Programmed cell death (apoptosis) of eosinophils represents an important component of this resolution process, limiting release of granule contents and triggering efferocytosis (the removal of apoptotic cells by phagocytes). Apoptosis is initiated by the activation of intracellular caspases, a family of cysteine proteases. Caspase activation primarily occurs as a result of changes in the balance of intracellular pro- and anti-apoptotic Bcl-2 family proteins. Mcl-1, an anti-apoptotic Bcl-2 protein has been shown to play a pivotal role in the regulation of neutrophil apoptosis. Pharmacological down-regulation of Mcl-1 initiates apoptosis and promotes the resolution of neutrophil-dominant inflammation. The importance of Mcl-1 in the regulation of apoptosis was shown using cyclin-dependent kinase inhibitors (CDKis), where induction of neutrophil apoptosis by CDKis was due to down-regulation of intracellular Mcl-1. Apoptotic cells display distinct surface molecules known as ‘eat-me’ signals that identify them for phagocytosis by macrophages and other phagocytes. One key receptor involved in the removal of apoptotic cells from tissue is the receptor tyrosine kinase Mer, a member of the Tyro3/Axl/Mer (TAM) family, which recognises the ‘eat me’ signal phosphatidylserine expressed on apoptotic cells. In the absence of Mer expression, clearance of apoptotic cells is compromised delaying the resolution of neutrophil-dominant inflammation. However, the roles of Mcl-1 and Mer in eosinophil apoptosis and clearance, respectively, and the resolution of allergic inflammation are not known. Asthma is a chronic inflammatory lung disease characterised by shortness of breath, airway obstruction, wheeze, non-specific bronchial hyper-responsiveness, excessive airway mucus production and an eosinophil dominant inflammatory infiltrate. The persistent presence of eosinophils in the lung, in chronic asthma, is likely due to a combination of excessive eosinophil recruitment and activation together with impaired eosinophil apoptosis. Investigation into the underlying mechanisms of these processes in allergic airway disease is of critical importance, as blocking eosinophil recruitment and/or promoting eosinophil apoptosis could provide a therapeutic approach to reduce associated eosinophil-mediated tissue damage. Understanding the regulation of eosinophil apoptosis and phagocytic clearance may identify novel pharmacological targets to enhance the resolution of allergic inflammation. We hypothesise that Mcl-1 and Mer play vital roles in the successful resolution of allergic airway inflammation. To investigate this hypothesis, we have used pharmacological and genetic manipulation of intracellular eosinophil Mcl-1 levels, and phagocyte Mer expression, to determine the role they play in the regulation of eosinophil apoptosis and phagocytic clearance of apoptotic eosinophils, respectively. Human and mouse eosinophils were cultured, and rates of constitutive and CDKi-induced apoptosis were determined, to investigate eosinophil apoptosis in vitro. Mice expressing human Mcl-1 (hMcl-1) were used to determine the effect of over-expression of Mcl-1 on eosinophil viability in vitro. The effect of hMcl-1 on eosinophil viability and disease severity in vivo was determined using an ovalbumin-induced model of allergic airway inflammation, which mimicked the symptoms of human asthma. Apoptotic eosinophils were co-incubated with macrophages in vitro to investigate the capacity for phagocytosis by different macrophage populations. Apoptotic cell clearance was further investigated using a Mer-kinase-dead mouse, which lacked Mer expression, to determine the role of Mer-dependent phagocytosis on the process of resolution of inflammation in vivo. Over-expression of Mcl-1 in eosinophils significantly delayed both constitutive and CDKi-induced apoptosis in vitro. In vivo in the ovalbumin-induced model of allergic airway inflammation, over-expression of Mcl-1 resulted in a significantly increased number of eosinophils in the lung and delayed rate of resolution of allergic airway inflammation. Alveolar and bone marrow-derived macrophages exhibited Mer-dependent phagocytosis of eosinophils, which was significantly reduced by an inhibitor of Mer kinase activity (BMS777607) or lack of macrophage Mer expression. The absence of Mer expression resulted in a significant increase in the number of apoptotic eosinophils in the lung together with a delayed rate of resolution of allergic airway inflammation in vivo. Together this work has shown that delayed rates of eosinophil apoptosis and impaired phagocytic clearance both delayed the resolution of allergic airway inflammation. These data suggest that both Mcl-1 and Mer are pivotal for the successful regulation of eosinophil apoptosis and phagocytic clearance of apoptotic eosinophils in asthma and may provide attractive novel therapeutic targets.
63

Investigating the role of eosinophils in cardiac remodelling following myocardial infarction

Toor, Iqbal Singh January 2018 (has links)
Myocardial infarction (MI) occurs following acute thrombotic occlusion of a coronary artery, and triggers a robust inflammatory response. Within hours, neutrophils are recruited to the infarcted myocardium followed by the infiltration of pro-inflammatory Ly6Chi monocytes. Transition from the pro-inflammatory macrophage phenotype (M1) to an anti-inflammatory, pro-resolution phenotype (M2-like) is critical to successful infarct healing. Interventions that polarize macrophages towards an anti-inflammatory 'M2-like' phenotype improve infarct healing in the experimental MI mouse model and reduce subsequent adverse remodelling of the myocardium, but the endogenous mechanisms that regulate repair are not well understood. Furthermore, differences in the resolution of inflammation in C57BL/6 and BALB/c mice, which are two of the commonly used wild-type mouse strains in experimental MI have not been characterised. We previously found that low peripheral blood eosinophil count is associated with increased short-term risk of mortality in low-intermediate risk patients with ischaemic heart disease. This suggests that eosinophils may have a role in the successful remodelling and repair of the heart following myocardial infarction. Eosinophils express a number of immuno-modulating cytokines and lipid mediators implicated in the resolution of inflammation. Increasingly prominent is interleukin-4 (IL-4), a cytokine that has been found to maintain the anti-inflammatory M2-like phenotype in macrophages. We therefore hypothesised that IL-4Rα signalling and recruitment of eosinophils to the myocardium following infarction are key in regulating the subsequent inflammatory response and scar tissue formation during infarct repair and cardiac remodelling. Experimental MI was induced by permanent left anterior descending artery ligation in isofluorane anaesthetized 12-15 week-old male wild-type (WT) BALB/c, WT C57BL/6, IL4Rα-/-, IL-4Rαflox/-, IL-4Rαflox/-LysMCre mice and eosinophil-deficient ΔdblGATA mice. Cardiac function was characterised by high-resolution ultrasound and immune cell infiltration by flow cytometry of single cell infarct and remote zone tissue digests. Blood eosinophil count and 6-month all-cause mortality were assessed in 732 consecutive patients undergoing primary percutaneous coronary intervention for ST-segment elevation myocardial infarction (STEMI). The rate of mortality due to cardiac rupture was significantly higher in C57BL/6 mice in comparison with BALB/c mice at Day 7 post-MI. This was associated with a higher proportion of pro-inflammatory Ly-6Chi macrophages infiltrating the infarct zone tissue of C57BL/6 mice following MI. An accompanying reduction in the number of splenic Ly-6Chi monocytes post-MI, suggestive of splenic monocyte mobilisation, was seen in C57BL/6 mice but not found in BALB/c mice. Furthermore, C57BL/6 mice had a delayed transition in macrophage polarisation towards an anti-inflammatory phenotype. Disruption of IL4Rα signalling, in mice null for the IL4Rα gene, resulted in increased F4/80+ macrophage and pro-inflammatory Ly6Chi macrophage infiltration of the infarct zone and reduced expression of the anti-inflammatory macrophage marker CD206, compared to wild-type controls. Furthermore, expression of GATA3 and ST2, both associated with the immunosuppressive function of (CD4+ Foxp3+) regulatory T cells, was reduced in infarct zone regulatory T cells from IL4Rα-/- mice. These findings were associated with defective wound healing with impaired angiogenesis, increased scar size, disarrayed infarct zone collagen deposition, accompanied by modified expression of plod2 that encodes the collagen cross-linking enzyme lysyl hydroxylase 2. Resulting in greater left ventricular dilatation and loss of cardiac function, as well as a higher 7- day mortality due to cardiac rupture in IL4Rα-/- mice. This indicates that successful infarct repair requires the engagement of IL-4Rα signalling to facilitate the accumulation of anti-inflammatory macrophages and highly immunosuppressive ST2+ regulatory T cells in the heart following MI. Resident cardiac macrophages from naïve hearts of IL-4Rαflox/-LysMCre mice failed to undergo LysMCre-mediated deletion of the IL-4Rα gene, potentially because low or absent expression of Lyz2 (encoding lysozyme M). In both ST-elevation MI (STEMI) patients and mice after acute MI, there was a decline in peripheral blood eosinophil count, with activated eosinophils being recruited to the infarct zone and paracardial adipose tissue of mice. The transcription factors GATA-1 plays a role in the differentiation of eosinophils from eosinophil progenitor cells. Deletion of GATA-1 results in loss of the eosinophil lineage and has been exploited to develop the eosinophil-deficient ΔdblGATA mouse. ΔdblGATA mice were used to address the role of eosinophils in cardiac remodelling following MI. ΔdblGATA mice had increased left ventricular dilatation and reduced ejection fraction after induction of MI, relative to wild-type mice. ΔdblGATA mice had increased scar size with disarrayed infarct zone collagen deposition, accompanied by modified expression of the genes plod2 and lox, which are associated with collagen cross-linking. The proportion of CD206+ anti-inflammatory macrophages was less in the infarct zone of ΔdblGATA mice, but was restored by adoptive transfer of eosinophils from WT mice. Furthermore, adverse cardiac remodelling in eosinophil-deficient ΔdblGATA mice was rescued by provision of IL-4 complex following MI. In conclusion, an enhanced inflammatory response following MI underlies the increased risk of cardiac rupture seen with WT C57BL/6 mice in comparison to WT BALB/c mice. WT BALB/c mice are protected from cardiac rupture, which was associated with an absence of splenic monocyte mobilisation following ischaemic injury. The resolution of inflammation was found to be dependent on IL4Rα signalling which is crucial for cardiac repair and remodelling, through modulating inflammatory cell recruitment and phenotype, as well as scar formation. Eosinophils are recruited to the heart post-MI and are essential for regulating cardiac repair and remodelling, likely through provision of IL-4. Therefore, we were able to show that IL-4Rα signalling and recruitment of eosinophils to the myocardium following infarction are both key in regulating the subsequent inflammatory response and scar tissue formation during infarct healing and cardiac remodelling.
64

Modulation des mécanismes inflammatoires impliquant les polynucléaires éosinophiles au cours de la polypose naso-sinusienne associée à l'asthme / Regulation of inflammatory processes in chronic rhinosinusitis with nasal polyps. Immune profile of the eosinophil in relation with asthma

Mortuaire, Geoffrey 20 May 2015 (has links)
Contexte : La polypose naso-sinusienne (PNS) est une maladie inflammatoire chronique multifactorielle dont l’étiologie reste imprécise. Les acteurs de l’immunité innée et acquise sont diversement impliqués avec un rôle central joué par l’éosinophile(EO). L’asthme associé à la PNS est un facteur de résistance à la corticothérapie constituant à l’heure actuelle la seule option thérapeutique médicale.Objectifs : Caractériser sur le plan histologique, biologique et cellulaire les patients atteints de PNS afin de définir des profils phénotypiques inflammatoires en relation avec l’asthme et de préciser les mécanismes d’immuno-modulation de l’EO.Matériel: Une étude prospective était menée incluant les patients atteints de PNS réfractaires au traitement médical. Après recueil du consentement éclairé et accord institutionnel, les sécrétions nasales et les polypes étaient prélevés au bloc opératoire. Les corticoïdes locaux et généraux étaient au préalable arrêtés pendant 1 mois. Etaient réalisés un dosage des marqueurs d’inflammation (interleukine 5 (IL-5), Immunoglobulines E (IgE), eosinophil-derived neurotoxin (EDN), IL-9), une analyse histologique du polype sous microscopie optique et une analyse cytométrique des récepteurs d’adhésion (béta(β) intégrines, CD44), d’activation (CD69) et du récepteur alpha à l’IL-5 (IL-5Rα) sur les EOs purifiés sanguins et tissulaires. Ces paramètres étaient comparés à la présence d’un asthme.Résultats: Une classification histologique des polypes en 3 sous-types était établie: le polype œdémateux riche en EOs (64% des cas), le polype fibreux riche en collagène et glandes sous-muqueuses (9%) et le polype intermédiaire à composante mixte fibreuse et œdémateuse mais à prédominance éosinophile (27%). Il n’existait pas de corrélation entre cette classification et le statut clinique. L’asthme était associé à une plus forte éosinophilie tissulaire (p=0.026). Cette infiltration cellulaire était associée à la présence d’une plus forte concentration en IL-5, IgE et EDN dans les sécrétions nasales et dans le polype chez les patients asthmatiques (p≤0.04). La domiciliation des EOs dans le polype était favorisée par une diminution de l’expression membranaire des βintégrines et du CD44 après migration tissulaire (p≤0.02). Cette migration s’accompagnait d’une activation cellulaire CD69+ et d’une augmentation de l’expression membranaire de l’IL-5Rα sur les EOs purifiés quel que soit le statut clinique des patients. L’expression de l’IL-5Rα sur les EOs tissulaires était relativement plus faible en cas d’asthme associé (p≤0.04). Les analyses fonctionnelles par mise en culture d’EOs purifiés confirmaient le rôle anti-apoptique de l’IL-5 à forte concentration chez les patients asthmatiques. La co-culture IL-5/IL-9 permettait de renforcer cette action anti-apoptotique IL-5 dépendante en induisant l’expression membranaire de l’IL-5Rα chez les patients asthmatiques.Discussion: Ces résultats confirment le rôle majeur de l’EO en particulier chez les patients asthmatiques. L’architecture du polype conséquence du remodelage tissulaire ne détermine pas la cortico-résistance habituellement associée à l’asthme dans la mesure où les sous-types histologiques sont distribués de manière équivalente quel que soit le statut clinique des patients. Le profil inflammatoire (IL-5, IgE, IL-9) conditionne la domiciliation tissulaire des EOs en modulant l’expression des protéines d’adhésion et d’interaction. Il influence aussi la survie tissulaire des EOs en contrebalançant une diminution d’expression de l’IL-5Rα IL-5 dépendante par une synergie d’action IL-5/IL-9 anti-apoptotique [...] / Background: The chronic rhinosinusitis with nasal polyps (CRSwNP) is a plurifactorial inflammatory disease whose etiology is still unknown. Innate and acquired immune agents are key factors with a pivotal role of the eosinophil (EO). Asthma is recognized as a major factor of medical failure. Objectives: Setting histological, biological and cellular patterns of inflammation in CRSwNP in accordance with the asthmatic status of the patient and describing the membrane immune phenotype of EOs both in blood and polyp compartments. Materiel: A prospective study was conducted enrolling patients with medical refractory CRSwNP. With institutional review board agreement, nasal secretions and polyp specimens were harvested through endoscopic surgical procedure. A 1-month corticosteroid wash-out was required prior to surgery. Inflammatory biomarkers measurements (interleukin-5 (IL-5), Immunoglobulins E (IgE), eosinophil-derived neurotoxin (EDN), IL-9), histological study on microscopic slides and cytometric analyses of adhesion receptors (beta(β) integrins, CD44), activation proteins (CD69) and of the IL-5 receptor alpha (IL-5Rα) were performed on purified EOs collected from the blood and the polyp. Data were compared with the asthmatic status of the patients.Results: A histological classification was established. Three subtypes were observed. The edematous polyp with huge EO infiltration (64%), the fibrous polyp with a collagen framework and a large amount of seromucous glands (9%) and the intermediate polyp with mixed fibro-edematous stroma and EO infiltration (27%). No correlation was described between this classification and the clinical status. CRSwNP with concomitant asthma was depicted with a major eosinophilia (p=.026). High IL-5, IgE and IL-9 concentrations in nasal secretions and polyp were also associated with asthma (p≤.04). EO homing into the polyp was partly promoted by the β integrins and CD44 membrane downregulation observed during tissular migration (p≤.02). CD69 activation process and IL-5Rα surface enhancement on EOs were observed in CRSwNP with or without asthma during tissue migration. The IL-5Rα expression was slightly reduced in asthmatic CRSwNP patients by comparison with the non-asthmatic counterparts (p≤.04). In vitro analyses showed the anti-apoptotic function of IL-5 in EOs of the asthmatic patients. The co-culture with IL-5 and IL-9 led to the up-regulation of the IL-5Rα surface expression. Discussion: Our results stress the major role of the EO in particular in asthmatic CRSwNP patients. The remodeling process implied in the polyp formation is not directly involved in the corticosteroid resistance as the 3 subtypes of polyps were evenly observed whatever the clinical status. High IL-5, IgE and Il-9 environment promotes EO polyp migration and activation by the regulation of adhesion and activation proteins on the EO membrane. The synergistic action of pro Th2 cytokines (IL-5/IL-9) balances the IL-5Rα downregulation observed in high IL-5 rate conditions. Conclusion: The cellular and inflammatory phenotype profiles in CRSwNP are correlated to the asthmatic status of the patients. Taken together, our results suggest that processes of immune modulation are key factors of inflammatory homeostasis in CRSwNP. Intricate mechanisms of up and down regulation of cytokines receptors expression could be involved in the incomplete efficacy of targeted therapies whose evaluation is still pending.
65

Associação do polimorfismo do gene da proteína catiônica eosinofílica com a eosinofilia tecidual associada aos tumores em carcinomas espinocelulares de boca / Association of eosinophil cationic protein gene polymorphism with tumor-associated tissue eosinophilia in oral squamous cell carcinomas

Michele Conceição Pereira 22 August 2008 (has links)
A proteína catiônica eosinofílica (ECP) presente nos grânulos específicos dos eosinófilos apresenta atividade citotóxica, particularmente para células tumorais, entretanto a função exata dos eosinófilos e de seus produtos nas neoplasias malignas continua obscura. O objetivo desse trabalho foi investigar a prevalência do polimorfismo 434(G>C) do gene ECP em pacientes com carcinoma espinocelular (CEC) de boca e sua correlação com a eosinofilia tecidual associada aos tumores (TATE), bem como com as características demográficas, clínicas e microscópicas. O genótipo 434 do gene ECP em 165 pacientes saudáveis e em 157 pacientes com CEC de boca, tratados no Hospital do Câncer A.C. Camargo entre 1984 a 2002, foi detectado pela clivagem da seqüência específica de DNA amplificada com a enzima de restrição PstI e análise dos produtos de clivagem pela eletroforese em gel de agarose. A TATE foi determinada por análise morfométrica. A associação entre os genótipos, a intensidade da TATE e as variáveis demográficas, clínicas e microscópicas foi avaliada pelo teste qui-quadrado ou teste exato de Fisher. As análises das sobrevidas global, livre de doença e específica por câncer foram feitas pelo estimador limite de Kaplan-Meier e a comparação das curvas de sobrevida foi realizada utilizando-se o teste log-rank. Notou-se uma predominância dos indivíduos heterozigotos para o polimorfismo 434(G>C) do gene ECP. Nenhuma diferença estatística significativa foi obtida entre os diferentes genótipos, a intensidade da TATE e as variáveis demográficas, clínicas e microscópicas. Uma maior freqüência de esvaziamento cervical bilateral, recidiva local, embolização vascular, comprometimento das margens cirúrgicas e realização de radioterapia pós-operatória foi observada nos pacientes com CEC de boca, TATE intensa e genótipos 434GC/CC. Não houve correlação estatística significativa entre os diferentes genótipos 434 do gene ECP e as sobrevidas global, livre de doença e específica por câncer. Baseados em nossos resultados, concluímos que houve uma tendência de os pacientes com CEC de boca, intensa eosinofilia tecidual e genótipos 434GC/CC do gene ECP apresentarem uma evolução clínica desfavorável, quando comparados aos indivíduos com genótipo 434GG, provavelmente pela presença de uma variante genética dessa proteína com propriedades citotóxicas alteradas. / Eosinophil cationic protein (ECP), found in secretory granules of human eosinophils, presents cytotoxic activity, particularly against cancer cells. The specific functional role of eosinophils in solid malignant tumors remains unclear. The aim of this study was to investigate the prevalence of the ECP-gene polymorphism 434(G>C) in oral squamous cell carcinoma (OSCC) patients and its association with tumor-associated tissue eosinophilia (TATE), as well as demographic, clinical and microscopic variables. The 434 genotypes in the ECP-gene of 165 healthy individuals and 157 OSCC patients, submitted to surgical treatment at the Hospital A.C. Camargo from 1984 to 2002, were detected by cleavage of the amplified DNA sequence with restriction enzyme PstI and analyses of the cleaved product by agarose gel electrophoresis. TATE, in OSCC, was obtained by morphometric analysis. Chisquare test or Fishers exact test was used to analyze the association among ECP-gene polymorphism 434(G>C), TATE, demographic, clinical and microscopic variables. Diseasefree survival and overall survival were calculated by the Kaplan-Meier product-limit actuarial method and the comparison of the survival curves were performed using log rank test. Most of healthy individuals and OSCC patients showed the genotype 434GC. There was no statistical association among 434 genotypes, TATE intensity and demographic, clinical or microscopic variables of OSCC patients. Higher frequency of bilateral neck dissection, local recurrence, vascular embolization, involved resection margins and postoperative radiotherapy was detected in OSCC patients with intense TATE and 434GC/CC genotypes. No statistically significant differences on survival rates were found among 434 genotypes. In conclusion, these results suggest a tendency of worse clinical outcome in OSCC patients with intense TATE and 434GC/CC genotypes, probably due an ECP genetic variant with altered cytotoxic activity.
66

Granulocyte Adhesion to Matrix Proteins and the Effect on the Release of Granule Proteins : Development of a Simple Method and its Application in Experimental and Clinical Studies

Xu, Xiaoyan January 2001 (has links)
<p>Granulocyte adhesion and release of their granule proteins are key steps during selective accumulation of a certain cell to an inflammatory site. Eosinophils are specifically recruited to sites of allergic inflammation and parasitic infection, whereas neutrophil influx predominates in bacterial infection and rheumatoid arthritis. </p><p>A simple, reliable and convenient method was developed for the measurement of granulocyte adhesion and release of granule proteins by using the normal population of granulocytes. The design allows simultaneous quantitative assessment of eosinophil and neutrophil adhesion to proteins and degranulation. </p><p>Using this method, manganese ions (Mn<sup>2+</sup>) induced a higher level of eosinophil adhesion to fibronectin, fibrinogen and albumin as compared with neutrophils. PMA induced comparable levels of eosinophil and neutrophil adhesion. F-MLP stimulated a rapid, short-term adhesion of neutrophils to fibrinogen. </p><p>In the same conditions PMA alone stimulated a dose-dependent release of ECP from cells that adhered to both fibronectin and fibrinogen. Meanwhile, Mn<sup>2+</sup> amplified the release of ECP induced by PMA. Furthermore, release of ECP was shown to be associated with cell death.</p><p>PMA, in combination with Mn<sup>2+</sup>, induced a marked release of ~ 80%of the intracellular content of lactoferrin and HNL in neutrophils. PMA or f-MLP alone induced 30-40% release of lactoferrin and HNL. A maximal release of MPO of 15-20% was obtained from neutrophils stimulated by PMA and Mn<sup>2+</sup>. Release of lactoferrin and HNL showed a significant negative relationship to the viability of cells.</p><p>Stimulated by PMA, eosinophils from pollen-atopic patients during early pollen season displayed a markedly enhanced adhesion and release of ECP of eosinophils compared with eosinophils from the references. Priming with IL-5 caused a significantly higher adhesion and release of ECP by eosinophils in response to PMA. GM-CSF priming enhanced eosinophil adhesion in response to PAF and PMA plus Mn<sup>2+</sup>, but did not enhance the release of ECP.</p><p>In conclusion, the assay allows a simple quantification of eosinophil and neutrophil adhesion, as well as degranulation by using the normal population of granulocytes. Cellular adhesion plays an important role in the regulation of both eosinophil and neutrophil degranulation, but adhesion and degranulation can be induced separately.</p>
67

Granulocyte Adhesion to Matrix Proteins and the Effect on the Release of Granule Proteins : Development of a Simple Method and its Application in Experimental and Clinical Studies

Xu, Xiaoyan January 2001 (has links)
Granulocyte adhesion and release of their granule proteins are key steps during selective accumulation of a certain cell to an inflammatory site. Eosinophils are specifically recruited to sites of allergic inflammation and parasitic infection, whereas neutrophil influx predominates in bacterial infection and rheumatoid arthritis. A simple, reliable and convenient method was developed for the measurement of granulocyte adhesion and release of granule proteins by using the normal population of granulocytes. The design allows simultaneous quantitative assessment of eosinophil and neutrophil adhesion to proteins and degranulation. Using this method, manganese ions (Mn2+) induced a higher level of eosinophil adhesion to fibronectin, fibrinogen and albumin as compared with neutrophils. PMA induced comparable levels of eosinophil and neutrophil adhesion. F-MLP stimulated a rapid, short-term adhesion of neutrophils to fibrinogen. In the same conditions PMA alone stimulated a dose-dependent release of ECP from cells that adhered to both fibronectin and fibrinogen. Meanwhile, Mn2+ amplified the release of ECP induced by PMA. Furthermore, release of ECP was shown to be associated with cell death. PMA, in combination with Mn2+, induced a marked release of ~ 80%of the intracellular content of lactoferrin and HNL in neutrophils. PMA or f-MLP alone induced 30-40% release of lactoferrin and HNL. A maximal release of MPO of 15-20% was obtained from neutrophils stimulated by PMA and Mn2+. Release of lactoferrin and HNL showed a significant negative relationship to the viability of cells. Stimulated by PMA, eosinophils from pollen-atopic patients during early pollen season displayed a markedly enhanced adhesion and release of ECP of eosinophils compared with eosinophils from the references. Priming with IL-5 caused a significantly higher adhesion and release of ECP by eosinophils in response to PMA. GM-CSF priming enhanced eosinophil adhesion in response to PAF and PMA plus Mn2+, but did not enhance the release of ECP. In conclusion, the assay allows a simple quantification of eosinophil and neutrophil adhesion, as well as degranulation by using the normal population of granulocytes. Cellular adhesion plays an important role in the regulation of both eosinophil and neutrophil degranulation, but adhesion and degranulation can be induced separately.
68

Gastroesophageal reflux disease in adults : the Kalixanda study : a population-based endoscopic study /

Ronkainen, Jukka, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.
69

Characterisation of eosinophil activity markers : relation to allergic inflammation and apoptosis /

Nopp, Anna, January 2002 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2002. / Härtill 5 uppsatser.
70

Allergic inflammation in children with pet allergy and asthma : mechanisms, markers and clinical consequences /

Lönnkvist, Karin, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 5 uppsatser.

Page generated in 0.0337 seconds