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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.
21

Mensuração do superóxido e apoptose neutrofílica em cães azotêmicos e urêmicos /

Soeiro, Carolina Soares. January 2011 (has links)
Orientador: Paulo César Ciarlini / Banca: Mary Marcondes / Banca: Raimundo Souza Lopes / Resumo: O metabolismo oxidativo e apoptose dos neutrófilos de pacientes humanos nefropatas e sua relação com as toxinas urêmicas tem sido, nos últimos anos, amplamente investigados devido sua importância como elemento imunossupressor. Recentemente surgiram evidências de que a uremia causa disfunção neutrofílica em cães nefropatas, porém não se sabe se o acúmulo de compostos nitrogenados, que também ocorrem nas azotemias não renais, igualmente afeta a função dos neutrófilos. O objetivo do presente estudo foi testar ex vivo a hipótese de que plasmas urêmicos e azotêmicos igualmente afetam o metabolismo oxidativo e a apoptose dos neutrófilos de cães. Para tal, neutrófilos de cães sadios foram isolados e incubados com plasma autólogo, plasma de cão azotêmico e urêmico. A produção de superóxido, com e sem o estimulo com PMA, foi estimada pelo método de redução do nitroazul tetrazólio (NBT) e por citometria de fluxo capilar utilizando-se a sonda hidroetidina (HE). A taxa de neutrófilos viáveis, em apoptose inicial e final, foi quantificada por citometria utilizando-se Anexina V-PE e o índice apoptótico mensurado pelo método morfométrico. A produção de superóxido gerada pelos neutrófilos isolados, em ambos os tratamentos (plasma urêmico e azotêmico) apresentou significante redução (p<0,05). Já a apoptose dos neutrófilos de cães sadios foi acelerada, quando incubados com plasmas urêmico e azotêmico. Pode-se concluir que os componentes presentes nos plasmas urêmicos e azotêmicos alteram ex vivo o metabolismo oxidativo e a apoptose dos neutrófilos, fortalecendo a hipótese de que in vivo ambas condições podem comprometer a imunidade inata de cães / Abstract: The oxidative metabolism and apoptosis of neutrophils from human patients with nephropathy and its relation with uremic toxins has been widely investigated in the last years because of its importance as an immunosuppressive element. Recently evidences suggests that uremia causes neutrophil dysfunction in dogs with renal disease, but it is unclear whether the accumulation of nitrogen compounds, which also occur in non-renal azotemia, can as well affect the role of neutrophils. The objective of this study was to test ex vivo the hypothesis that uremic and azotemic plasma also affects the oxidative metabolism and apoptosis of neutrophils in dogs. To this end, neutrophils from healthy dogs were isolated and incubated with autologous plasma, plasma of azotemic and uremic dog. The production of superoxide, with and without PMA stimulation was estimated by the method of nitroblue tetrazolium reduction (NBT) and by capillary flow cytometry using the hydroethidine probe (HE). The rate of viable, in early and late apoptosis neutrophils was quantified by flow cytometry using Annexin V-PE and theapoptotic index was measured by morphometric method. The production of superoxide generated by isolated neutrophils in both treatments (azotemic and uremic plasma) showed a significant reduction (p <0.05). Neutrophil apoptosis of healthy dogs was accelerated when incubated with uremic and azotemic plasma. In conclusion, the components present in uremic and azotemic plasma change ex vivo the oxidative metabolism and apoptosis of neutrophils, emphasizing the hypothesis that in vivo both conditions can compromise the innate immunity of dogs / Mestre
22

Tratamento inicial do choque por hemorragia controlada: avaliação tardia do efeito sinérgico de pentoxifilina e solução salina hipertônica / Hemodynamic and inflammatory response to volume replacement with crystalloid or hypertonic saline with and without pentoxifylline on experimental hemorrhagic shock

Luiz André Magno 18 March 2010 (has links)
INTRODUÇÃO. O trauma grave está associado a complexas alterações hemodinâmicas e microcirculatórias. A hipovolemia resultante da perda sanguínea e a inflamação desencadeada pelo trauma tecidual, além da própria isquemia tecidual sistêmica, são os principais fatores que levam a estas alterações. A solução salina hipertônica hiperoncótica (HSD) e a pentoxifilina vem sendo propostas como opções na ressuscitação volêmica do choque hemorrágico, mostrando efeito de modulação da resposta inflamatória e eficácia na restauração dos parâmetros hemodinâmicos. OBJETIVOS. Avaliar a evolução dos mediadores inflamatórios e do burst oxidativo durante 4 horas, após reposição volêmica inicial no tratamento do choque hemorrágico controlado, com três diferentes tipos de solução: Ringer lactato, solução hipertônica hiperoncótica (HSD) e solução hipertônica hiperoncótica associada a pentoxifilina (PTX). MÉTODOS. Anestesiamos e instrumentamos 20 porcos da raça Landrace de 28-32 kg. 5 animais foram randomizados para grupo Sham (apenas anestesiados e monitorizados) e outros 15 submetidos a choque hemorrágico controlado, com pressão arterial média (PAM) mantida em 40 mmHg por 30 minutos. Após o choque 5 animais foram tratados com 32 ml/kg de ringer lactato (grupo RL), 5 animais com 4 ml/kg de HSD (grupo HSD) e 5 animais com 4 ml/kg de HSD + 25 mg/kg de pentoxifilina. Além de medidas hemodinâmicas sistemicas e regionais, procedemos a determinação do burst oxidativo dos neutrófilos circulantes e dos mediadores inflamatórios (TNF alfa, interleucina 1, interleucina 6 e interleucina 10). RESULTADOS. Os animais dos grupos HSD e PTX apresentaram diminuição significativa do burst oxidativo após a reposição volêmica, ao contrário do grupo RL, que apresentou comportamento contrário (p<0,001 para HSD versus RL e PTX versus RL após tratamento). TNF alfa e interleucinas também apresentaram valores estáveis nos grupos tratados com HSD e PTX, enquanto nos animais tratados com RL houve aumento importante destes mediadores. O HSD mostrou-se ineficaz em normalizar algumas variáveis regionais e sitêmicas (p<0,05 após tratamento em T0 para HSD versus Sham e HSD versus PTX), apresentando melhora quando associado a pentoxifilina. CONCLUSÕES. Em modelo experimental de choque hemorrágico controlado, durante observação de 4 horas, a solução salina hipertônica hiperoncótica, utilizada como solução de reposição volêmica em volume de 4ml/kg de peso, demonstrou causar menor ativação de neutrófilos e menor produção de mediadores inflamatórios quando comparada a solução de Ringer lactato. Quando associada a pentoxifilina 25 mg/kg seus efeitos na modulação da resposta inflamatória foram semelhantes. / INTRODUCTION. Major trauma is associated with complex hemodynamic and microcirculatory changes. Volume depletion resulting from blood loss and inflammation triggered by tissue trauma, besides the systemic tissue ischemia, are the main factors leading to these changes. Hypertonic saline hyperoncotic (HSD) and pentoxifylline has been proposed as options in the resuscitation of hemorrhagic shock, showing the effect of modulation of the inflammatory response and efficacy in the restoration of hemodynamic parameters. OBJECTIVES. To evaluate the progression of inflammatory mediators and oxidative burst during 4 hours after initial resuscitation in the treatment of hemorrhagic shock, with three different solutions: Ringer lactate, hypertonic hyperoncotic solution (HSD) and hypertonic hyperoncotic solution associated with pentoxifylline (PTX). METHODS. anesthetized and instrumented 20 Landrace pigs of 28-32 kg 5 animals were randomized to Sham group (only anesthetized and monitored) and 15 submitted to hemorrhagic shock. The mean arterial pressure (MAP) was maintained at 40 mmHg by 30 minutes. After shock 5 animals were treated with 32 ml / kg Ringer\'s lactate (RL group), 5 animals with 4 ml / kg HSD (HSD group) and 5 animals with 4 ml / kg of HSD + 25 mg / kg pentoxifylline. In addition to systemic and regional hemodynamic parameters, we determine the oxidative burst of circulating neutrophils and inflammatory mediators (TNF-alpha, interleukin 1, interleukin 6 and interleukin 10). RESULTS. The animals in the HSD and PTX groups showed a significant decrease in oxidative burst after resuscitation, unlike the RL group, which showed an opposite (p<0.001 for HSD versus RL and RL PTX versus after treatment). TNF alpha and interleukins also showed stable values in the groups treated with HSD and PTX, whereas in animals treated with RL was significant increase of these mediators. The HSD was ineffective in normalizing some regional and systemic hemodynamic variables (p<0.05 after treatment at T0 for HSD versus HSD versus Sham and PTX), which improved when combined with pentoxifylline. CONCLUSIONS. In an experimental model of hemorrhagic shock during the observation of 4 hours, hypertonic saline hyperoncotic used as a solution for volume replacement in volume 4ml/Kg weight, shown to cause less activation of neutrophils and decreased production of inflammatory mediators when compared to Ringer\'s lactate. When coupled with pentoxifylline 25 mg / kg effects on modulation of inflammatory response were similar.
23

Mecanismo da interação entre a proteína dissulfeto isomerase e a NADPH oxidase: papel regulatório sobre a produção de espécies reativas de oxigênio em fagócitos profissionais / Mechanisms involved in the interaction of protein disulfide isomerase with NADPH oxidase: regulatory role on the reactive oxygen species generation by professional phagocytes

Antonio Marcus de Andrade Paes 08 May 2009 (has links)
INTRODUÇÃO: A ativação da NADPH oxidase de neutrófilos requer o acoplamento das subunidades citosólicas p47phox, p67phox, p40phox e Rac2 ao componente de membrana citocromo b558. Em trabalhos anteriores, nós mostramos que as isoformas vasculares da oxidase são reguladas pela proteína dissulfeto isomerase (PDI), uma chaperona redox. Neste trabalho, nós utilizamos um sistema cellfree semirecombinante como ferramenta para investigar o papel da PDI na ativação da NADPH oxidase do neutrófilo. RESULTADOS: Inibidores da PDI, scrambled RNAse (100g/mL) ou bacitracina (1mM), praticamente suprimiram a geração de superóxido. Para avaliação dos efeitos do estado redox da PDI sobre a atividade da oxidase, amostras de PDI foram previamente oxidadas (H2O2; 0,5 mM) ou reduzidas (DTT; 0,5 mM). A PDI oxidada (100 nM) aumentou a produção de superóxido em aproximadamente 30%, enquanto a mesma concentração de PDI reduzida promoveu efeito inverso, inibindo a atividade do complexo. A adição de um peptídeo contendo a seqüência peptídica do sítio ativo da PDI inibiu a produção de superóxido em 70%. Dados de imunolocalização e colocalização demonstraram que a interação da PDI com a subunidade p47phox parece ser intensificada pelo estímulo com PMA e envolvem modificações do estado redox de ambas as proteínas. CONCLUSÕES: Nossos dados confirmam a associação física e funcional entre a PDI e o complexo NADPH oxidase. Além disso, sugerem que a PDI exerça um importante papel como fator de regulação redox da ativação da oxidase. / Activation of the leukocyte NADPH oxidase requires the assembly of the cytosolic subunits p47phox, p67phox and p40phox and Rac2 with the membranebound cytochrome b558. We have previously shown that the vascular oxidase is regulated by the redox chaperone protein disulfide isomerase (PDI). Taking advantage of the semirecombinant cellfree system, we sought to investigate the role of PDI in the activation of neutrophil NADPH oxidase. The PDI thiol inhibitors scrambled RNase (100g/mL) or bacitracin (1mM), almost suppressed superoxide generation. In order to investigate if the redox status of PDI thiols could modulate superoxide generation, PDI was oxidized or reduced by treatment with H2O2 (0.5mM) or DTT (1mM), respectively. Oxidized PDI increased by 30% superoxide production, while reduced PDI diminished superoxide generation also in 30%. The addition of a peptide (1M) containing PDI´s exact active site sequence inhibited superoxide production by 70 %. Immuno and colocalization data demonstrated the interaction of PDI with the subunit p47phox to be intensified by PMA stimulation and to involve redox status exchange of both proteins. Our data confirm the physical and functional association between PDI and the oxidase complex. Moreover, we show a relevant role for PDI as a redoxdependent supportive factor for NADPH oxidase activation.
24

Effet de la source du sélénium sur le statut du sélénium, de la GSH-Px et sur le système immunitaire des bovins de boucherie

Jinane, Noureddine 12 1900 (has links)
Résumé L’objectif de cette étude était de déterminer les effets de la source de sélénium sur les concentrations de Se et de GSH-Px des vaches de boucherie (n =33) et leurs veaux et sur des paramètres immunitaires des veaux. Deux groupes de vaches ont reçu 3 mg/j/animal de Se organique ou inorganique dans le minéral. Le troisième groupe n'a pas été supplémenté en Se et leurs veaux ont été divisés en deux sous-groupes, l’un des deux a reçu une injection de sélénite de sodium (0,087 mg/Kg) à la naissance. Le Se et la GSH-Px ont été respectivement mesurés par HPLC-UV et par cinétique enzymatique. La phagocytose, la flambée respiratoire et le ratio CD4:CD8ont été évalués par des kits commerciaux et les IgG totales ont été mesurés par immunodiffusion radiale. La supplémentation de Se a augmenté significativement le Se sérique et colostral (P<0,02) et la GSH-Px(P≤0,04) pour les vaches et leurs veaux avec un effet significativement plus élevé pour le Se organique. Le Se du lait a augmenté de façon significative uniquement avec la source organique du Se (P≤0,0007). L’injection du Se chez les veaux a permis une augmentation significative mais temporaire (P<0,0001) du Se sérique. La supplémentation en Se n’a pas influencé les paramètres immunitaires mesurés (P>0,01, non significatif après correction de Bonferroni). Nous concluons que la supplémentation en Se améliore le niveau du Se colostral, lacté et sérique ainsi que la GSH-Px pour les vaches et leurs veaux sans effet sur les paramètres immunitaires mesurés des veaux. Mots clés: Sélénium, veaux de boucherie, phagocytose, flambée respiratoire, anticorps, ratio CD4:CD8, GSH-Px. / Abstract The aims of this study were to determine the effects of selenium (Se) supplementation sources (organic and inorganic) on Se and GSH-Px concentrations of beef cows (n=33) and their calves and on immune parameters of the calves. Two groups of cows were given daily 3 mg of either organic or inorganic Se in mineral supplement starting from 12 weeks before calving until weaning. The third group had no Se added into the diet and their calves were divided into two subgroups either injected or not with 0.087 mg/kg of sodium selenite after birth. Serum Se and whole blood GSH-Px were respectively measured by HPLC-UV and by kinetic-enzymatic technique. Calves immune parameters were evaluated using commercial kits for phagocytosis, respiratory burst and CD4:CD8 ratio and radial immunodiffusion for total IgG concentrations. In cows and calves, Se supplementation increased significantly serum and colostrum Se concentrations (P<.02) with significant higher effect for organic source. However, milk Se concentrations increased significantly only with the organic source (P≤.0007). Se supplementation increased GSH-Px concentrations in cows (P≤.04) and their calves (P≤.0004); organic source induced a higher effect than inorganic one in calves (P≤.0004). Se injection in calves allowed a temporary increase (P<.0001) of serum Se concentrations. No significant differences were noticed throughout the experiment for all of the immune parameters measured (P>.01, not significant after Bonferroni adjustment). Our results showed that Se supplementation improved colostrum, milk and serum Se and GSH-Px concentrations in cows and their calves without effect on the measured immune parameters in calves. Key words: selenium, beef calves, phagocytosis, respiratory burst, antibodies, CD4:CD8 ratio, GSH-Px.
25

Effet de la source du sélénium sur le statut du sélénium, de la GSH-Px et sur le système immunitaire des bovins de boucherie

Jinane, Noureddine 12 1900 (has links)
Résumé L’objectif de cette étude était de déterminer les effets de la source de sélénium sur les concentrations de Se et de GSH-Px des vaches de boucherie (n =33) et leurs veaux et sur des paramètres immunitaires des veaux. Deux groupes de vaches ont reçu 3 mg/j/animal de Se organique ou inorganique dans le minéral. Le troisième groupe n'a pas été supplémenté en Se et leurs veaux ont été divisés en deux sous-groupes, l’un des deux a reçu une injection de sélénite de sodium (0,087 mg/Kg) à la naissance. Le Se et la GSH-Px ont été respectivement mesurés par HPLC-UV et par cinétique enzymatique. La phagocytose, la flambée respiratoire et le ratio CD4:CD8ont été évalués par des kits commerciaux et les IgG totales ont été mesurés par immunodiffusion radiale. La supplémentation de Se a augmenté significativement le Se sérique et colostral (P<0,02) et la GSH-Px(P≤0,04) pour les vaches et leurs veaux avec un effet significativement plus élevé pour le Se organique. Le Se du lait a augmenté de façon significative uniquement avec la source organique du Se (P≤0,0007). L’injection du Se chez les veaux a permis une augmentation significative mais temporaire (P<0,0001) du Se sérique. La supplémentation en Se n’a pas influencé les paramètres immunitaires mesurés (P>0,01, non significatif après correction de Bonferroni). Nous concluons que la supplémentation en Se améliore le niveau du Se colostral, lacté et sérique ainsi que la GSH-Px pour les vaches et leurs veaux sans effet sur les paramètres immunitaires mesurés des veaux. Mots clés: Sélénium, veaux de boucherie, phagocytose, flambée respiratoire, anticorps, ratio CD4:CD8, GSH-Px. / Abstract The aims of this study were to determine the effects of selenium (Se) supplementation sources (organic and inorganic) on Se and GSH-Px concentrations of beef cows (n=33) and their calves and on immune parameters of the calves. Two groups of cows were given daily 3 mg of either organic or inorganic Se in mineral supplement starting from 12 weeks before calving until weaning. The third group had no Se added into the diet and their calves were divided into two subgroups either injected or not with 0.087 mg/kg of sodium selenite after birth. Serum Se and whole blood GSH-Px were respectively measured by HPLC-UV and by kinetic-enzymatic technique. Calves immune parameters were evaluated using commercial kits for phagocytosis, respiratory burst and CD4:CD8 ratio and radial immunodiffusion for total IgG concentrations. In cows and calves, Se supplementation increased significantly serum and colostrum Se concentrations (P<.02) with significant higher effect for organic source. However, milk Se concentrations increased significantly only with the organic source (P≤.0007). Se supplementation increased GSH-Px concentrations in cows (P≤.04) and their calves (P≤.0004); organic source induced a higher effect than inorganic one in calves (P≤.0004). Se injection in calves allowed a temporary increase (P<.0001) of serum Se concentrations. No significant differences were noticed throughout the experiment for all of the immune parameters measured (P>.01, not significant after Bonferroni adjustment). Our results showed that Se supplementation improved colostrum, milk and serum Se and GSH-Px concentrations in cows and their calves without effect on the measured immune parameters in calves. Key words: selenium, beef calves, phagocytosis, respiratory burst, antibodies, CD4:CD8 ratio, GSH-Px.
26

Vliv stárnutí na změny v hematologických a imunologických znacích u sýkory koňadry (Parus major) / Effect of ageing on haematological and immunological traits in great tit (Parus major)

Krajzingrová, Tereza January 2019 (has links)
v III. Abstract (EN) According to the Disposable soma theory, senescence is mainly influenced by adaptive allocation of resources among the physical growth, reproduction and self-maintaining processes, which depend on expected survival of an individual. The amount of allocated resources may be influenced by external environmental factors such as heavy metal pollution or by inner factor e.g. reproduction. The aim of my diploma thesis was to clarify the relationships between senescence, selected haematological traits, reproduction and efficiency of innate immunity mechanism. Moreover, we are interested in the role of heavy metal pollution in ageing and haematology. The heterophiles to lymphocytes ratio (H/L) was used as a marker of long-term stress caused by these physiological expenses. This study summarizes partial data collected within the long-term research of great tits (Parus major) in Prague, Czech Republic, I participated in. We have more than 300 samples of repeatedly captured individuals at our disposal. The structure of this unique dataset allows us to observe changes in the traits of our interest during an avian lifespan. Our results show that during aging, males experience a noticeable increase in the H/L ratio compared to females. Although we have not found the effect of age on the brood size,...
27

The Responses of Human Neutrophils to Tobacco Smoke Components

Al-Shibani, Nouf Khider January 2012 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Tobacco smoking is considered a major modifiable risk factor for periodontal disease. Tobacco contains about 6700 compounds and almost 4000 compounds of these have been identified in tobacco smoke. Nicotine is the addictive ingredient in tobacco and has been shown to affect multiple cellular processes. Cigarette smoke condensate (CSC) is the particulate matter of smoke. It is believed to be a powerful inducer of inflammatory responses. Neutrophils are the first line of host defense and are critical cells in the maintenance of periodontal health through their role in the control of bacteria, but they can also contribute to the progression of periodontal disease by the production and release of reactive oxygen species (ROS). Virulence factors from periodontal pathogens, such as Porphyromonas gingivalis (P. gingivalis), stimulate the respiratory burst of neutrophils. In this dissertation, three studies aimed at understanding the oxidative activity of neutrophils when stimulated with either nicotine, cigarette smoke condensate (CSC) or four other components of tobacco smoke (2-naphthylamine, hydroquinone, acrolein, and acetaldehyde) with or without P. gingivalis supernatant. The release of matrix metalloproteinase-9 (MMP-9) was also examined. ROS production increased significantly when the neutrophils were stimulated with nicotine. P. gingivalis induced the maximum ROS production when compared to all the other components examined. The combination of nicotine and P. gingivalis did not have an additive effect on ROS production. Nicotine significantly increased the MMP-9 release from the neutrophils. On the contrary, CSC inhibited ROS production at all the concentrations examined. The combination of CSC and P. gingivalis resulted in the inhibition of ROS production. MMP-9 release was also increased from the CSC-treated neutrophils. The four other tobacco smoke components examined affected ROS production and MMP-9 release differently. These projects demonstrated that CSC inhibited the ROS production from neutrophils, which can be attributed to several components in tobacco smoke that may include acrolein and hydroquinone. More research is needed to determine the mechanisms of inhibition and if other tobacco components are involved in ROS inhibition
28

The modulation of polymorphonuclear neutrophil function by cytotoxic necrotizing factor type 1 -- expressing uropathogenic Escherichia coli /

Davis, Jon Michael. January 2005 (has links) (PDF)
Thesis (Ph. D.)--Uniformed Services University of the Health Sciences, 2005. / Typescript (photocopy).

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