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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.
31

Intermediate Biomarkers of Cancer Risk are Altered by Different Intensity Levels of Physical Activity in Older Adults

Esbjörnson, Malin January 2022 (has links)
Introduction: Cancer is the leading cause of death worldwide, and the risk increases as age increases. Additionally, chronic inflammation is highly prevalent in older adults, and is associated with cancer. In this respect, physical activity (PA) seems to act as a preventive tool of both cancer, and chronic inflammation, by exerting anti-inflammatory properties. However, current knowledge on links between physical activity and inflammatory biomarkers in older adults remains limited. Therefore, the present study aims to investigate the association between objectively assessed time in different physical activity intensities and pro-, and anti-inflammatory intermediated biomarkers of cancer risk in older European adults. Material and Methods: Men and women older adults (aged 65-79 years; N = 888) were recruited from four European centers. Accelerometer-based assessment of daily time spent sedentary (SED), in light (LPA), and in moderate-to-vigorous (MVPA) PA was conducted. The inflammatory markers C-reactive protein (CRP), tumor necrosis factor-α, interleukin-6, tumor growth factor-β1, leptin, interleukin-10 and adiponectin were assessed in blood samples using enzyme-linked immunosorbent assay (ELISA), and standardized procedures were used to define indicators of the metabolic syndrome. Linear regression analysis based on isotemporal substitution modelling with 30-minutes periods of different physical activity intensities was used and the analysis was stratified by biological sex. Results: Replacing 30 minutes of either SED or LPA with a corresponding time in MVPA was associated to reduced CRP levels in older men and women (P < 0.05). In older women, reduced leptin levels were associated with reallocation of time spent in SED with both LPA and MVPA, and with reallocation of time spent in LPA with MVPA (P < 0.05). In older men, replacing time in SED with either LPA or MVPA (P < 0.01) resulted in significantly reduced leptin levels. Finally, reallocation of 30 minutes in either SED or LPA with MVPA was associated with elevated adiponectin levels in older women only (P < 0.05). Conclusion: This study suggests that different important cancer-related biomarkers of chronic inflammation in older adults are affected by different intensity thresholds of physical activity and that the impact of physical activity is independent of several important confounding factors, including smoking, disease risk and medication.
32

<b>Evaluating Systemic Inflammation by Comparing Lipid Mediators and the Platelet and Plasma Proteome of Postpartum Dairy Cows</b>

Jillian Michaela Grantz (18433119) 28 April 2024 (has links)
<p dir="ltr">Inflammation is a vital aspect of the immune response and functions to maintain homeostasis and protect the host against tissue injury or infection. However, excessive or prolonged inflammation can lead to health disorders and production losses in dairy cows. inflammation is a normal part of the tissue response during parturition. However, exacerbated systemic inflammation in the early postpartum has been associated with decreased milk production, decreased reproductive efficiency, and increased disease severity. Several processes contribute to systemic inflammation in dairy cows, such as liver oxidative stress, bacterial or endotoxin translocation during increased gastrointestinal permeability (e.g., lipopolysaccharide; LPS), and postpartum adipose tissue and skeletal muscle mobilization. However, there is limited knowledge of the mechanisms underlying systemic inflammation in postpartum dairy cows. Several studies have identified potent lipid mediators known as oxylipins as direct mediators of inflammation. Some differences have been identified in dairy cows when comparing the oxylipin profile throughout lactation and between cows suffering from different disorders. In our first study, we evaluated the plasma oxylipin profile of dairy cows suffering from systemic inflammation in the first week after parturition. Cows were classified into one of four systemic inflammation categories based on plasma haptoglobin (Hp) concentrations and plasma oxylipin profiles were identified by mass spectrometry. The results from this study identified several oxylipins of interest that warrant further research to confirm their presence in dairy cows with systemic inflammation and to evaluate their biological function associated with the postpartum inflammatory process. Endocannabinoids are soluble mediators associated with inflammation in humans, mouse models, and, more recently, dairy cows. While studies have demonstrated endocannabinoids to contribute to inflammation in the adipose tissue of dairy cows, no studies have evaluated the circulating presence of these mediators in cows suffering from systemic inflammation. Therefore, our second study sought to further evaluate the plasma oxylipin and endocannabinoid profiles of dairy cows suffering from systemic inflammation. In this study, we compared the oxylipin and endocannabinoid profiles of dairy cows categorized into high- and low-inflammation groups based on plasma Hp concentrations. We identified oxylipins associated with inflammation and found differences in the plasma endocannabinoid profile of high-inflammation cows compared to low-inflammation cows. Platelets are well understood for their function in hemostasis, though more recently, they have been studied for their ability to modulate the immune and inflammatory response. Presently, no studies exist elucidating the role of platelets on systemic inflammation in dairy cows. In addition to evaluating plasma oxylipin and endocannabinoid profiles in our second study, we determined if changes in platelets are associated with systemic inflammation in postpartum dairy cows. Proteomic analysis was completed on isolated platelets and plasma collected from dairy cows with high and low inflammation based on plasma Hp concentrations. Results from this study provide the first evidence demonstrating differences in the platelet and plasma proteomes between cows suffering from high inflammation and cows with low inflammation. The lipidomic and proteomic profiles described in these studies identified differences between cows suffering from systemic inflammation and apparently healthy cows. The results from these studies suggest platelets could contribute to an inflammatory state and have identified specific oxylipins, endocannabinoids, and proteins that may contribute to systemic inflammation in dairy cows by impairing the immune response or directly exerting an inflammatory function. More research is needed to fully understand the <i>in vitro </i>and <i>in vivo </i>function of the many lipid mediators and proteins identified in these studies and their ability to contribute to an exacerbated systemic inflammatory response in dairy cows.</p>
33

Perfil inflamatório de pacientes submetidos à endarterectomia de carótida e sua relação com doença periodontal crônica / Inflammatory profile of patients undergoing carotid endarterectomy and its relationship to chronic periodontal disease

Adriana Moura Foz 10 June 2015 (has links)
A relação entre periodontite e doenças cardiovasculares (DCV) tem sido amplamente discutida, embora os mecanismos de interação não estejam claros. Foi sugerido que pacientes com periodontite apresentam inflamação sistêmica e um pequeno aumento no risco cardiovascular. Patógenos periodontais foram encontrados em placas de ateroma, mas a influência destes microrganismos na aterosclerose ainda não é compreendida. O objetivo primário deste estudo foi delinear o perfil inflamatório sistêmico de pacientes submetidos à endarterectomia carotídea. Os objetivos secundários foram associar o perfil inflamatório dos participantes à condição periodontal e à presença de patógenos orais encontrados na cavidade oral e em placas de ateroma. Trinta e cinco pacientes submetidos à endarterectomia carotídea foram incluídos neste estudo. Antes da cirurgia vascular, um exame clínico periodontal foi realizado e foram coletadas amostras de sangue, saliva e biofilme subgengival. Durante a endarterectomia, uma amostra da placa de ateroma foi coletada. As amostras de soro foram testadas com o ensaio imunoenzimático de alta sensibilidade Multiplex para dezessete marcadores de células Th17. Amostras de saliva, biofilme subgengival e placa de ateroma foram submetidas ao PCR quantitativo para avaliação de dez patógenos periodontais. Este estudo foi capaz de detectar vários marcadores inflamatórios circulantes, o que indica a presença de inflamação sistêmica como uma característica da população. T. forsythia foi o microrganismo mais frequentemente encontrado em amostras de ateroma (37% das amostras). Níveis de T. forsythia em amostras de ateroma foram positivamente correlacionados com os níveis séricos de IL-7, IL-6, IL-17, IL-13, IL-12p70, IFN-?, GCS-F (p<0,05) e IL-10 (p<0,01). Níveis séricos de IL-2 foram positivamente correlacionados com os concentrações salivares de P. intermedia, P. endodontalis (p<0,05) e T. denticola (p<0,01). Níveis séricos de TNF-? foram positivamente correlacionados com concentrações salivares de P. endodontalis (p<0,01). Concentrações de P. endodontalis em amostras subgengivais foram correlacionadas positivamente com IL-2 (p<0,05). A inflamação periodontal (PISA) foi positivamente correlacionada com IL-2 (p<0,05). A coexistência de patógenos periodontais comuns na cavidade oral e na placa de ateroma está associada a um estado inflamatório sistêmico, o que poderia ser relevante para a compreensão dos mecanismos que ligam periodontite com DCV. / The relationship between periodontitis and cardiovascular diseases (CVD) has been widely discussed, although the mechanisms of interaction are not clear. It has been suggested that patients with periodontitis exhibit systemic inflammation and mild increase in future cardiovascular risk. Periodontal pathogens have been found in atheromatous plaques, but their exact role in atherosclerosis are not yet undertstood. The primary aim of this study was to screen the systemic inflammation profile in patients undergoing carotid endarterectomy. The secondary aims were to associate participant\'s inflammatory profiles with periodontal status and the presence of periodontal pathogens found in oral cavity and atheromatous plaques. Thirty-five patients who underwent carotid endarterectomy were enrolled in this study. Prior to the vascular surgery, a clinical periodontal exam was conducted, and samples of blood, saliva and subgingival biofilm were collected. During endarterectomy, a sample of the atheromatous plaque was retrieved. Serum samples were assayed with high sensitivity Multiplex assay for seventeen Th17 biomarkers. Saliva, subgingival biofilm and atheromatous plaque samples were submited to quantitative PCR for ten periodontal pathogens. This study was able to detect several circulating inflammatory markers, indicating the systemic inflammatory burden as a characteristic of this population. T. forsythia was the more frequent microorganism found in atheromatous samples (37% of the samples). T. forsythia titres in atheromatous samples were positively correlated with serum levels of IL-7, IL-6, IL-17, IL-13, IL-12p70, IFN- ?, GCS-F (p<0.05) and IL-10 (p<0.01). Circulating levels of IL-2 were positively correlated with salivary titres of P. intermedia, P. endodontalis (p<0.05) and T. denticola (p<0.01). Circulating levels of TNF-? were positively correlated with salivary titres of P. endodontalis (p<0.01). Subgingival levels of P. endodontalis were positively correlated with IL-2 (p<0.05). Periodontal inflammation (PISA) was positively correlated with IL-2 (p<0.05). The co-existence of common periodontal pathogens in the oral cavity and in atheromatous plaque is associated with a systemic inflammatory state that could be relevant to understanding the mechanisms linking periodontitis to CVD.
34

Níveis sistêmicos e periodontais de citocinas durante a gestação : correlações e efeito da terapia periodontal

Fiorini, Tiago January 2012 (has links)
A doença periodontal tem sido frequentemente associada ao parto pretermo. A plausibilidade biológica para tal associação baseia-se na hipótese de uma inflamação sistêmica de baixa intensidade de origem periodontal. Entretanto, os estudos de intervenção que investigaram o efeito da terapia periodontal durante a gestação não observaram reduções significativas na incidência de prematuridade. Como diversas citocinas têm sido associadas tanto a doença periodontal quanto ao parto pretermo, cogita-se que elas desempenhem um papel importante na associação observada. Até o presente momento, pouco se sabe a respeito da correlação entre os níveis de citocinas no soro e no fluído crevicular gengival (FCG), assim como do efeito da terapia periodontal sobre esses marcadores de inflamação em gestantes. O objetivo desta tese foi avaliar a relação entre níveis sistêmicos e periodontais de biomarcadores inflamatórios relacionados com a resposta imune periodontal e também com os mecanismos de parto. Também investigou-se o efeito da terapia periodontal sobre os níveis dessas citocinas durante a gestação e 30 dias após o parto. Esta tese é composta por dois estudos que utilizaram uma sub-amostra de mulheres que haviam sido recrutadas para um ensaio clínico randomizado maior que investigou o efeito da terapia periodontal sobre a incidência de prematuridade. Mulheres entre 18-35 anos e com até 20 semanas de gestação foram aleatoriamente alocadas para receber tratamento periodontal não cirúrgico completo até a 24a semana de gestação (grupo teste) ou apenas uma consulta de uma remoção de cálculo supragingival (grupo controle). Dados clínicos e amostras de sangue e FCG foram coletadas no início do estudo, entre 26-28 semanas de gestação e 30 dias após o parto. Quatro sítios periodontais por paciente foram aleatoriamente selecionados para coleta de FCG entre aqueles com maior profundidade de sondagem. Os níveis de IL-1β, IL-6, IL-8, IL-10, IL- 12p70 e FNT-α foram analisados por citometria de fluxo. No estudo 1, investigou-se a correlação e concordância entre os níveis periodontais e sistêmicos dessas citocinas em 100 pacientes, utilizando dados coletados até a 20a semana de gestação. As pacientes apresentaram extensa inflamação e limitada destruição periodontal. A correlação entre os níveis de citocinas no soro e no FCG foi baixa e não significativa, com exceção da IL-12p70 que mostrou uma correlação moderada, porém significativa, entre as duas fontes (r=0.32, p=0.001). Os níveis de citocinas observados no FCG explicaram menos de 10% dos respectivos níveis observados no soro, com exceção da IL-12p70 em que eles foram responsáveis por 23% dos níveis séricos (p=0.0001, r2=0.23). A profundidade de sondagem e o sangramento a sondagem estiveram significativamente associados com os níveis de IL-1β, IL-6 e IL-8 no FCG, mas tiveram efeitos limitados sobre os níveis sistêmicos de todas as citocinas. No estudo 2, comparou-se o efeito da terapia periodontal durante a gestação (n=30) com uma consulta única de remoção de cálculo supragingival (n=30) sobre os níveis periodontais e sistêmicos dessas citocinas durante a gestação e 30 dias após o parto. Após o tratamento, uma redução drástica da inflamação periodontal foi observada no grupo teste, com o percentual de sangramento a sondagem reduzindo de 49.62% para 11.66% dos sítios (p<0.001). A terapia também reduziu significativamente os níveis de IL-1β e IL-8 (p<0.001) no FCG. Entretanto, nenhum efeito significativo do tratamento foi observado em relação aos níveis sistêmicos dessas citocinas. Após o parto, os níveis periodontais de IL-1β no grupo teste permaneceram significativamente menores que no grupo controle, enquanto que nenhuma diferença foi observada em relação aos níveis sistêmicos das outras citocinas avaliadas. Pode-se concluir que os níveis de citocinas no soro e FCG não estão significativamente associados em mulheres com extensa inflamação mas limitada destruição periodontal. Embora a terapia periodontal durante a gestação reduza significativamente o nível de citocinas no FCG, ela parece não ter um impacto considerável sobre os níveis sistêmicos desses biomarcadores. / Periodontal disease has been frequently associated with preterm birth. The biological plausibility for this association relies on the hypothesis of a low-grade systemic inflammation originated from periodontal disease. However, clinical studies that investigated the effect of periodontal therapy during pregnancy did not observe significant reductions in the incidence of prematurity. Several cytokines have been associated with both periodontal disease and preterm birth, and might play a key role in the observed association. To date, little is known about the correlation between serum and gingival crevicular fluid (GCF) cytokine levels, as well as the effect of periodontal therapy on these inflammatory markers in pregnant women. The aim of this thesis was to investigate the relationship between periodontal and systemic levels of inflammatory biomarkers related to periodontal immune response and also with the mechanisms of delivery. We also investigated the effect of periodontal therapy on serum and GCF cytokine levels during pregnancy and 30 days postpartum. This thesis consists of two studies that used a sub-sample of women who had been previously enrolled in a larger randomized controlled trial investigating the effect of periodontal therapy on the incidence of preterm birth. Women aged between 18-35 years and up to 20 weeks of gestation were randomly assigned to receive comprehensive nonsurgical periodontal treatment before the 24th gestational week (test group) or a single appointment of supragingival calculus removal (control group). Clinical data, blood and GCF samples were collected at baseline, between 26-28 weeks of gestation and 30 days postpartum. Four periodontal sites per patient were randomly selected for GCF collection among those with deepest probing depth. IL-1β, IL-6, IL-8, IL-10, IL-12p70 and TNF-α levels were analyzed using a cytometric bead array. In the study one, we investigated the correlation and agreement between periodontal and systemic levels of these cytokines in 100 patients, using data collected until 20 weeks of gestation. Patients presented widespread periodontal inflammation but limited destruction. The correlation between serum and GCF cytokine levels was low and not significant, except for IL-12p70, which showed a moderate but significant correlation between the two sources (r = 0.32, p = 0.001). The GCF cytokine levels observed explained less than 10% of the respective serum levels observed, except for IL-12p70, which was responsible for 23% of serum levels (p = 0.0001, r2 = 0.23). Probing depth and bleeding on probing were significantly associated with IL-1β, IL-6 and IL-8 GCF levels, but had limited effects on systemic levels of all cytokines. In the study two, we compared the effect of periodontal therapy during pregnancy (n=30) or a single appointment for supragingival calculus removal (n=30) on periodontal and systemic levels of these cytokines during pregnancy and 30 days postpartum. After treatment, a remarkable reduction of periodontal inflammation was observed in the test group, with bleeding on probing reducing from 49.62% to 11.66% of the sites (p<0.001). Periodontal therapy also significantly reduced IL-1β and IL-8 GCF levels (p<0.001). However, no significant differences due to therapy were observed regarding systemic levels of these cytokines. After delivery, IL-1β GCF levels in the test group remained significantly lower than in the control group, whereas no difference was observed for systemic levels of any other cytokine evaluated. It can be concluded that serum and GCF cytokine levels are not significantly associated in women with widespread periodontal inflammation but limited destruction. Although periodontal therapy during pregnancy significantly reduces GCF cytokine levels, it seems to have a negligible impact on systemic levels of these biomarkers.
35

Perfil inflamatório de pacientes submetidos à endarterectomia de carótida e sua relação com doença periodontal crônica / Inflammatory profile of patients undergoing carotid endarterectomy and its relationship to chronic periodontal disease

Foz, Adriana Moura 10 June 2015 (has links)
A relação entre periodontite e doenças cardiovasculares (DCV) tem sido amplamente discutida, embora os mecanismos de interação não estejam claros. Foi sugerido que pacientes com periodontite apresentam inflamação sistêmica e um pequeno aumento no risco cardiovascular. Patógenos periodontais foram encontrados em placas de ateroma, mas a influência destes microrganismos na aterosclerose ainda não é compreendida. O objetivo primário deste estudo foi delinear o perfil inflamatório sistêmico de pacientes submetidos à endarterectomia carotídea. Os objetivos secundários foram associar o perfil inflamatório dos participantes à condição periodontal e à presença de patógenos orais encontrados na cavidade oral e em placas de ateroma. Trinta e cinco pacientes submetidos à endarterectomia carotídea foram incluídos neste estudo. Antes da cirurgia vascular, um exame clínico periodontal foi realizado e foram coletadas amostras de sangue, saliva e biofilme subgengival. Durante a endarterectomia, uma amostra da placa de ateroma foi coletada. As amostras de soro foram testadas com o ensaio imunoenzimático de alta sensibilidade Multiplex para dezessete marcadores de células Th17. Amostras de saliva, biofilme subgengival e placa de ateroma foram submetidas ao PCR quantitativo para avaliação de dez patógenos periodontais. Este estudo foi capaz de detectar vários marcadores inflamatórios circulantes, o que indica a presença de inflamação sistêmica como uma característica da população. T. forsythia foi o microrganismo mais frequentemente encontrado em amostras de ateroma (37% das amostras). Níveis de T. forsythia em amostras de ateroma foram positivamente correlacionados com os níveis séricos de IL-7, IL-6, IL-17, IL-13, IL-12p70, IFN-?, GCS-F (p<0,05) e IL-10 (p<0,01). Níveis séricos de IL-2 foram positivamente correlacionados com os concentrações salivares de P. intermedia, P. endodontalis (p<0,05) e T. denticola (p<0,01). Níveis séricos de TNF-? foram positivamente correlacionados com concentrações salivares de P. endodontalis (p<0,01). Concentrações de P. endodontalis em amostras subgengivais foram correlacionadas positivamente com IL-2 (p<0,05). A inflamação periodontal (PISA) foi positivamente correlacionada com IL-2 (p<0,05). A coexistência de patógenos periodontais comuns na cavidade oral e na placa de ateroma está associada a um estado inflamatório sistêmico, o que poderia ser relevante para a compreensão dos mecanismos que ligam periodontite com DCV. / The relationship between periodontitis and cardiovascular diseases (CVD) has been widely discussed, although the mechanisms of interaction are not clear. It has been suggested that patients with periodontitis exhibit systemic inflammation and mild increase in future cardiovascular risk. Periodontal pathogens have been found in atheromatous plaques, but their exact role in atherosclerosis are not yet undertstood. The primary aim of this study was to screen the systemic inflammation profile in patients undergoing carotid endarterectomy. The secondary aims were to associate participant\'s inflammatory profiles with periodontal status and the presence of periodontal pathogens found in oral cavity and atheromatous plaques. Thirty-five patients who underwent carotid endarterectomy were enrolled in this study. Prior to the vascular surgery, a clinical periodontal exam was conducted, and samples of blood, saliva and subgingival biofilm were collected. During endarterectomy, a sample of the atheromatous plaque was retrieved. Serum samples were assayed with high sensitivity Multiplex assay for seventeen Th17 biomarkers. Saliva, subgingival biofilm and atheromatous plaque samples were submited to quantitative PCR for ten periodontal pathogens. This study was able to detect several circulating inflammatory markers, indicating the systemic inflammatory burden as a characteristic of this population. T. forsythia was the more frequent microorganism found in atheromatous samples (37% of the samples). T. forsythia titres in atheromatous samples were positively correlated with serum levels of IL-7, IL-6, IL-17, IL-13, IL-12p70, IFN- ?, GCS-F (p<0.05) and IL-10 (p<0.01). Circulating levels of IL-2 were positively correlated with salivary titres of P. intermedia, P. endodontalis (p<0.05) and T. denticola (p<0.01). Circulating levels of TNF-? were positively correlated with salivary titres of P. endodontalis (p<0.01). Subgingival levels of P. endodontalis were positively correlated with IL-2 (p<0.05). Periodontal inflammation (PISA) was positively correlated with IL-2 (p<0.05). The co-existence of common periodontal pathogens in the oral cavity and in atheromatous plaque is associated with a systemic inflammatory state that could be relevant to understanding the mechanisms linking periodontitis to CVD.
36

Bioactivities of Milk Polar Lipids in Influencing Intestinal Barrier Integrity, Systemic Inflammation, and Lipid Metabolism

Zhou, Albert Lihong 01 May 2013 (has links)
The purpose of lactation is for nutrient provision and also importantly for protection from various environmental stressors. Milk polar lipids reduce cholesterol, protect against bacterial infection, reduce inflammation and help maintain gut integrity. Dynamic interactions within dietary fat, lipid metabolism, gut permeability and inflammatory cytokines remain unclear in the context of obesity and systemic inflammation. A rat model and three mouse models were developed to test the hypotheses that dietary milk polar lipids may affect lipid metabolism and intestinal integrity and may protect against systemic inflammation in the context of stressful diet, systemic inflammation, and obesity. The milk polar lipids isolates had complex effects on lipid metabolism and associated gene expression in the rat model. There were complex dynamics in lipid metabolism, gut permeability and systemic inflammation at different time points in all mouse models. The milk phospholipids increased gut permeability in genetic and diet-induced obesity and during the lipopolysaccharide (LPS) -induced inflammation. The phospholipids increased the plasma LPS level in genetic obesity and during the LPS stress. The phospholipids reduced liver mass and liver lipids in genetic obesity and during the LPS-induced inflammation. The phospholipids increased the body fat in the diet-induced obesity model. The milk gangliosides did not significantly affect gut permeability, systemic inflammation, and lipid metabolism in all three mouse models. Current estimate by the Centers for Disease Control is that about 1/3 Americans are obese (body mass index, BMI ≥ 30) and 1/3 Americans are overweight (25 ≤ BMI < 30). More than 25% of Americans today have a fatty liver which could lead to further health problems. The data from this dissertation shed light on the complicated interrelationships between gut permeability, systemic inflammation, and lipid metabolism in obesity. The results contribute to our understanding of the bioactivities of milk polar lipids and provide scientific evidence for the role of milk polar lipids rich materials in affecting biological functions. The study of the influence of milk polar lipids on gut barrier integrity adds new information on understanding the mechanisms of gut leakiness and recovery. The investigation of the impact of milk polar lipids on lipid metabolism reveals new perspectives for the development of diet-induced obesity.
37

Carbon monoxide in biological systems : An experimental and clinical study

Åberg, Anna-Maja January 2007 (has links)
Background: Carbon monoxide (CO) is a toxic gas, but it is also produced endogenously when haem is degraded. When produced in vivo, CO is believed to have positive biological effects. For example it activates the production of cyclic guanosine mono-phosphate and causes vasodilatation. CO is also believed to have anti-inflammatory properties by binding to Mitogen activated protein (MAP) kinase. Several studies in cells, mice and rats support this opinion regarding both the circulatory as well as the anti-inflammatory properties. However, studies in larger animals regarding circulatory effects have demonstrated contradictory results. The only study in humans regarding anti-inflammatory properties of CO could not demonstrate such effects. Methods: This thesis consists of four different models. In paper I a method for analysis of CO in blood was developed using gas chromatography. In paper II a porcine model was used to investigate the elimination time for CO. The pigs in paper II had a high concentration of CO administered via blood, and CO concentrations were followed over time and kinetically parameters calculated. Circulatory parameters were also measured to evaluate if there were any circulatory changes after CO administration. In paper III CO´s anti-inflammatory properties were investigated in an endotoxin-induced systemic inflammatory model in pigs. Paper III was a randomized study where one group inhaled CO and the other group served as controls. Plasma cytokine concentrations were measured and followed over time as an indication of the inflammatory state. In paper IV, CO concentrations in blood from blood donors at the Blood Centre in Umeå were investigated. The blood donors also completed a questionnaire about age, smoking history and other possible sources for exogenous contamination of CO in the blood. Results and conclusions: In paper I we developed a method suitable for analysis of low concentrations of CO in blood. The half-life of CO at levels of 250 µM in pigs was found to be 60 minutes. CO did not show anti-inflammatory effects after an endotoxin-induced systemic inflammation in pigs. In banked blood CO was present at concentrations up to six times higher than normal concentrations. This could be a risk when transfusing such blood to susceptible patients.
38

Bioactivities of Milk Polar Lipids in Influencing Intestinal Barrier Integrity, Systemic Inflammation, and Lipid Metabolism

Zhou, Albert Lihong 01 May 2013 (has links)
The purpose of lactation is for nutrient provision and also importantly for protection from various environmental stressors. Milk polar lipids reduce cholesterol, protect against bacterial infection, reduce inflammation and help maintain gut integrity. Dynamic interactions within dietary fat, lipid metabolism, gut permeability and inflammatory cytokines remain unclear in the context of obesity and systemic inflammation. A rat model and three mouse models were developed to test the hypotheses that dietary milk polar lipids may affect lipid metabolism and intestinal integrity and may protect against systemic inflammation in the context of stressful diet, systemic inflammation, and obesity. The milk polar lipids isolates had complex effects on lipid metabolism and associated gene expression in the rat model. There were complex dynamics in lipid metabolism, gut permeability and systemic inflammation at different time points in all mouse models. The milk phospholipids increased gut permeability in genetic and diet-induced obesity and during the lipopolysaccharide (LPS) -induced inflammation. The phospholipids increased the plasma LPS level in genetic obesity and during the LPS stress. The phospholipids reduced liver mass and liver lipids in genetic obesity and during the LPS-induced inflammation. The phospholipids increased the body fat in the diet-induced obesity model. The milk gangliosides did not significantly affect gut permeability, systemic inflammation, and lipid metabolism in all three mouse models. Current estimate by the Centers for Disease Control is that about 1/3 Americans are obese (body mass index, BMI ≥ 30) and 1/3 Americans are overweight (25 ≤ BMI < 30). More than 25% of Americans today have a fatty liver which could lead to further health problems. The data from this dissertation shed light on the complicated interrelationships between gut permeability, systemic inflammation, and lipid metabolism in obesity. The results contribute to our understanding of the bioactivities of milk polar lipids and provide scientific evidence for the role of milk polar lipids rich materials in affecting biological functions. The study of the influence of milk polar lipids on gut barrier integrity adds new information on understanding the mechanisms of gut leakiness and recovery. The investigation of the impact of milk polar lipids on lipid metabolism reveals new perspectives for the development of diet-induced obesity.
39

Inflammatory Markers, Respiratory Diseases, Lung Function and Associated Gender Differences

Ólafsdóttir, Inga Sif January 2011 (has links)
Systemic inflammation is associated with impaired lung function. Inflammation is part of asthma and chronic obstructive pulmonary disease (COPD), but the local and systemic inflammatory pattern differs. The overall aim was to evaluate systemic inflammatory markers in obstructive lung diseases and more specifically: To determine if CRP is related to respiratory symptoms, asthma, atopy and bronchial responsiveness (paper I), in a population sample from three countries (paper I and II); to evaluate if CRP is related to COPD, lung function and rate of lung function decline (paper II); to investigate the association of serum MMP-9 and TIMP-1 with lung function in a cross-sectional population based study (paper III); and finally, to study possible gender differences in the longitudinal association between CRP and lung function in a prospective population based study (paper IV). In the first study we reported that CRP was related to non-allergic asthma but not allergic asthma, and that CRP was related to respiratory symptoms such as wheeze, nocturnal cough and breathlessness after effort, but not associated with atopy or bronchial responsiveness. In the second study we found that COPD was more common in subjects in the highest CRP quartiles and higher CRP levels were associated with lower FEV1 values in both men and women, but the negative association between CRP and FEV1 was larger in men than women. The FEV1 decline was larger in men with high CRP levels, whereas no such association was found for women. In the third study we reported that lower FEV1 was associated with higher levels of MMP-9, TIMP-1 and their ratio MMP-9/TIMP-1. After stratification for gender this association was significant in men but not women. In the fourth study we found that CRP levels were associated with change in both FEV1 and FVC in men but not women. This association was found for both baseline CRP and change in CRP, confirming a stronger association between systemic inflammation and lung function decline in men than women. In conclusion, systemic inflammation is associated with non-allergic asthma but not allergic asthma. Our findings of a stronger association between the systemic inflammation and lung function impairment in men, but not women, may indicate a gender difference in the mechanisms of lung function decline.
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Níveis sistêmicos e periodontais de citocinas durante a gestação : correlações e efeito da terapia periodontal

Fiorini, Tiago January 2012 (has links)
A doença periodontal tem sido frequentemente associada ao parto pretermo. A plausibilidade biológica para tal associação baseia-se na hipótese de uma inflamação sistêmica de baixa intensidade de origem periodontal. Entretanto, os estudos de intervenção que investigaram o efeito da terapia periodontal durante a gestação não observaram reduções significativas na incidência de prematuridade. Como diversas citocinas têm sido associadas tanto a doença periodontal quanto ao parto pretermo, cogita-se que elas desempenhem um papel importante na associação observada. Até o presente momento, pouco se sabe a respeito da correlação entre os níveis de citocinas no soro e no fluído crevicular gengival (FCG), assim como do efeito da terapia periodontal sobre esses marcadores de inflamação em gestantes. O objetivo desta tese foi avaliar a relação entre níveis sistêmicos e periodontais de biomarcadores inflamatórios relacionados com a resposta imune periodontal e também com os mecanismos de parto. Também investigou-se o efeito da terapia periodontal sobre os níveis dessas citocinas durante a gestação e 30 dias após o parto. Esta tese é composta por dois estudos que utilizaram uma sub-amostra de mulheres que haviam sido recrutadas para um ensaio clínico randomizado maior que investigou o efeito da terapia periodontal sobre a incidência de prematuridade. Mulheres entre 18-35 anos e com até 20 semanas de gestação foram aleatoriamente alocadas para receber tratamento periodontal não cirúrgico completo até a 24a semana de gestação (grupo teste) ou apenas uma consulta de uma remoção de cálculo supragingival (grupo controle). Dados clínicos e amostras de sangue e FCG foram coletadas no início do estudo, entre 26-28 semanas de gestação e 30 dias após o parto. Quatro sítios periodontais por paciente foram aleatoriamente selecionados para coleta de FCG entre aqueles com maior profundidade de sondagem. Os níveis de IL-1β, IL-6, IL-8, IL-10, IL- 12p70 e FNT-α foram analisados por citometria de fluxo. No estudo 1, investigou-se a correlação e concordância entre os níveis periodontais e sistêmicos dessas citocinas em 100 pacientes, utilizando dados coletados até a 20a semana de gestação. As pacientes apresentaram extensa inflamação e limitada destruição periodontal. A correlação entre os níveis de citocinas no soro e no FCG foi baixa e não significativa, com exceção da IL-12p70 que mostrou uma correlação moderada, porém significativa, entre as duas fontes (r=0.32, p=0.001). Os níveis de citocinas observados no FCG explicaram menos de 10% dos respectivos níveis observados no soro, com exceção da IL-12p70 em que eles foram responsáveis por 23% dos níveis séricos (p=0.0001, r2=0.23). A profundidade de sondagem e o sangramento a sondagem estiveram significativamente associados com os níveis de IL-1β, IL-6 e IL-8 no FCG, mas tiveram efeitos limitados sobre os níveis sistêmicos de todas as citocinas. No estudo 2, comparou-se o efeito da terapia periodontal durante a gestação (n=30) com uma consulta única de remoção de cálculo supragingival (n=30) sobre os níveis periodontais e sistêmicos dessas citocinas durante a gestação e 30 dias após o parto. Após o tratamento, uma redução drástica da inflamação periodontal foi observada no grupo teste, com o percentual de sangramento a sondagem reduzindo de 49.62% para 11.66% dos sítios (p<0.001). A terapia também reduziu significativamente os níveis de IL-1β e IL-8 (p<0.001) no FCG. Entretanto, nenhum efeito significativo do tratamento foi observado em relação aos níveis sistêmicos dessas citocinas. Após o parto, os níveis periodontais de IL-1β no grupo teste permaneceram significativamente menores que no grupo controle, enquanto que nenhuma diferença foi observada em relação aos níveis sistêmicos das outras citocinas avaliadas. Pode-se concluir que os níveis de citocinas no soro e FCG não estão significativamente associados em mulheres com extensa inflamação mas limitada destruição periodontal. Embora a terapia periodontal durante a gestação reduza significativamente o nível de citocinas no FCG, ela parece não ter um impacto considerável sobre os níveis sistêmicos desses biomarcadores. / Periodontal disease has been frequently associated with preterm birth. The biological plausibility for this association relies on the hypothesis of a low-grade systemic inflammation originated from periodontal disease. However, clinical studies that investigated the effect of periodontal therapy during pregnancy did not observe significant reductions in the incidence of prematurity. Several cytokines have been associated with both periodontal disease and preterm birth, and might play a key role in the observed association. To date, little is known about the correlation between serum and gingival crevicular fluid (GCF) cytokine levels, as well as the effect of periodontal therapy on these inflammatory markers in pregnant women. The aim of this thesis was to investigate the relationship between periodontal and systemic levels of inflammatory biomarkers related to periodontal immune response and also with the mechanisms of delivery. We also investigated the effect of periodontal therapy on serum and GCF cytokine levels during pregnancy and 30 days postpartum. This thesis consists of two studies that used a sub-sample of women who had been previously enrolled in a larger randomized controlled trial investigating the effect of periodontal therapy on the incidence of preterm birth. Women aged between 18-35 years and up to 20 weeks of gestation were randomly assigned to receive comprehensive nonsurgical periodontal treatment before the 24th gestational week (test group) or a single appointment of supragingival calculus removal (control group). Clinical data, blood and GCF samples were collected at baseline, between 26-28 weeks of gestation and 30 days postpartum. Four periodontal sites per patient were randomly selected for GCF collection among those with deepest probing depth. IL-1β, IL-6, IL-8, IL-10, IL-12p70 and TNF-α levels were analyzed using a cytometric bead array. In the study one, we investigated the correlation and agreement between periodontal and systemic levels of these cytokines in 100 patients, using data collected until 20 weeks of gestation. Patients presented widespread periodontal inflammation but limited destruction. The correlation between serum and GCF cytokine levels was low and not significant, except for IL-12p70, which showed a moderate but significant correlation between the two sources (r = 0.32, p = 0.001). The GCF cytokine levels observed explained less than 10% of the respective serum levels observed, except for IL-12p70, which was responsible for 23% of serum levels (p = 0.0001, r2 = 0.23). Probing depth and bleeding on probing were significantly associated with IL-1β, IL-6 and IL-8 GCF levels, but had limited effects on systemic levels of all cytokines. In the study two, we compared the effect of periodontal therapy during pregnancy (n=30) or a single appointment for supragingival calculus removal (n=30) on periodontal and systemic levels of these cytokines during pregnancy and 30 days postpartum. After treatment, a remarkable reduction of periodontal inflammation was observed in the test group, with bleeding on probing reducing from 49.62% to 11.66% of the sites (p<0.001). Periodontal therapy also significantly reduced IL-1β and IL-8 GCF levels (p<0.001). However, no significant differences due to therapy were observed regarding systemic levels of these cytokines. After delivery, IL-1β GCF levels in the test group remained significantly lower than in the control group, whereas no difference was observed for systemic levels of any other cytokine evaluated. It can be concluded that serum and GCF cytokine levels are not significantly associated in women with widespread periodontal inflammation but limited destruction. Although periodontal therapy during pregnancy significantly reduces GCF cytokine levels, it seems to have a negligible impact on systemic levels of these biomarkers.

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