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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.
1

COUNTERREGULATORY EFFECTS OF PTX3 ON INFLAMMATION AND CELLULAR AGING

Slusher, Aaron L. 01 January 2018 (has links)
Pentraxin 3 (PTX3) is a vital regulator of innate immune function that has been shown to counterregulate pro-inflammatory signaling and protect against the development of cardiovascular disease (CVD). Less is known about how PTX3 may mitigate against CVD risk by regulating the pro-inflammatory response at the cellular level. Therefore, this dissertation details four manuscripts which aimed to examine the capacity of PTX3 to regulate the innate immune response of peripheral blood mononuclear cells (PBMCs) isolated from healthy adults. Manuscript 1 examined the capacity of PTX3 to alter the inflammatory milieu following in vitro stimulation of isolated PBMCs with the pro-inflammatory lipid palmitate. In addition, Manuscript 2 sought to examine how participation in acute exercise, a powerful anti-inflammatory behavior that reduces CVD risk, alters the inflammatory phenotype and response of mononuclear cells following ex vivo stimulation with lipopolysaccharide (LPS). Manuscript 3 aimed to further elucidate the potential impact of cardiorespiratory fitness on the capacity of PTX3 to stimulate an innate immune response prior to and immediately following acute exercise in aerobically trained and untrained individuals. Finally, Manuscript 4 investigated the impact of healthy aging on plasma PTX3 concentrations and its relationship with telomere length in middle-aged compared to young adults. The capacity of isolated PBMCs to express a key cellular mechanism involved in maintaining longer telomere lengths, human telomerase reverse transcriptase (hTERT), following cellular stimulation with LPS, PTX3, and PTX3+LPS was also examined to address a mechanism that might explain how persistent exposure of circulating immune cells to the age-related pro-inflammatory milieu contributes to the shortening of telomere lengths.
2

Pentraxin 3 in the lung and neutrophils

2013 August 1900 (has links)
Respiratory diseases are a major cause of human morbidity and mortality and are a leading cause of economic loss to livestock producers. The respiratory tract is constantly in contact with dust, bacteria, fungi, viruses and other pathogenic agents that are found in the air. Normally, the body has the ability to clear these foreign particles. However, physiological and environmental stresses can impair airway defense mechanisms resulting in establishment of pulmonary infections. The microbes and their products engage various receptors in the lung to activate epithelium, endothelium, macrophages, neutrophils and other cells. The activation of inflammatory cascade in the lung results in recruitment of neutrophils, damage to air-blood barrier and development of edema. Although there have been significant advances in our understanding of mechanisms of lung inflammation, there have been a lack of any significant advances in the development of new therapeutics to manage lung disease, which may suggest that our understanding of the inflammatory mechanisms is still incomplete. Pentraxin 3 (PTX3) is an innate immune protein which has been implicated in a diverse range of inflammatory processes, such as recruitment of cells and production of cytokines. PTX3 is an acute phase protein, with low or undetectable levels in the circulation of healthy humans and animals, and rapid, dramatic increase in inflammatory diseases. The expression and function of this protein has not been characterized in the lungs of domestic animal species. Because of potential implications of PTX3 in lung inflammation, I studied the expression of PTX3 in normal and inflamed lungs of calves, pigs, horses, foals and humans. Lungs from all of these species showed expression of PTX3 in airway epithelium, alveolar septa, vascular endothelium and inflammatory cells. Western blot performed on homogenates from normal and inflamed lungs from calves and pigs show an increased expression of PTX3 in inflamed lungs (P<0.05). Because protein function is influenced by its location in the cell, I clarified the subcellular expression of PTX3 with immuno-electron microscopy on normal and inflamed calf and horse lungs. PTX3 was localized on pulmonary intravascular macrophages, monocytes, neutrophils and, unexpectedly, platelets. PTX3 was also present in the nuclei of neutrophils, monocytes and pulmonary intravascular macrophages. Neutrophils are critical regulators of acute lung inflammation. Having observed PTX3 in neutrophils, I investigated the effect of E. coli lipopolysaccharide-induced activation on PTX3 in neutrophils in vitro. Neutrophils challenged with E. coli LPS were examined at 30, 60, 90 and 120 minutes after the treatment. Normal peripheral blood neutrophils showed PTX3 expression. Neutrophils activated with LPS appeared ruffled and showed loss of PTX3 expression at 30 minutes followed by recovery of the expression. Western blots performed on normal and activated neutrophil homogenates did not show any differences (P=0.05). Collectively, the data show PTX3 in normal and inflamed lungs across multiple species. PTX3 was also detected in normal and activated neutrophils. While the function of intriguing localization of PTX3 in the nuclei as well as in platelets is not known, the similarity of expression across the species suggest a role for PTX3 in lung inflammation.
3

Envolvimento da pentraxina 3 (PTX3) na patogÃnese da cistite hemorrÃgica induzida por ifosfamida em camundongos / Involvement of pentraxin 3 (PTX3) in the patogenesis of hemorrhagic cystitis induced by iphosphamide in mice

Markus Andret Cavalcante Gifoni 16 February 2008 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A cistite hemorrÃgica (CH) à um fenÃmeno inflamatÃrio frequentemente associado à quimioterapia com oxazafosforinas. Trata-se de uma resposta inflamatÃria inata à aÃÃo da AcroleÃna (ACR), metabÃlito hepÃtico comum à Ifosfamida (IFO) e à ciclofosfamida (CTX). O papel da resposta ao recrutamento de receptores toll-like (TLR) e do estÃmulo por TNF-&#945; e IL-1&#946; com envolvimentto de iNOS e COX-2 tem sido demonstrado neste fenÃmeno. Estudos recentes demonstram que a Pentraxina 3 (PTX3) assume papel de mediador inflamatÃrio em modelos de resposta inflamatÃria inata in vivo, sobretudo relacionada ao recrutamento de TLR. Desta forma, o presente estudo pretende investigar o possÃvel envolvimento de PTX3 na patogÃnese da CH induzida por ifosfamida em camundongos. Para isso, foi realizada quantificaÃÃo de RNAm por RT-PCR para PTX3 e IL-1&#946; em camundongos C57/ BL6 tratados com ifosfamida e salina. Em seguida, o modelo experimental da CH induzida por ifosfamida foi reproduzido em grupos de camundongos com hiperexpressÃo e nocauteados para PTX3 em comparaÃÃo com os respectivos controles do tipo selvagem e com grupos controle tratados com salina para posterior obtenÃÃo dos pesos vesicais Ãmidos (PVU), realizaÃÃo de anÃlise histomorfomÃtrica, imunohistoquÃmica e quantificaÃÃo de RNAm por RT-PCR para PTX3, IL-1&#946;, TNF-&#945; e iNOS. Os animais transgÃnicos e seus controles foram sacrificados com tempos de 3h e 12h apÃs o tratamento, enquanto os nocauteados e seus controles foram sacrificados com 12 horas do tratamento. Finalmente, a CH em animais C57/ BL6 foi modulada com o prÃ-tratamento com Talidomida, Pentoxifilina, MESNA, Amifostina e Aminoguanidina para a posterior marcaÃÃo imunohistoquÃmica com PTX3, IL-1&#946;, TNF-&#945; e iNOS. Observou-se que o RNAm de PTX3 està cerca de 70 vezes mais expresso em animais com CH, contra uma razÃo de expressÃo de 10 para IL-1&#946;. Animais trangÃnicos para PTX3 tÃm reduÃÃo inicial da resposta inflamatÃria com expressÃo inferior de PTX3 e TNF-&#945; e expressÃo aumentada de iNOS e intensificaÃÃo da inflamaÃÃo ao tempo de 12 horas, com expressÃo superior dos mediadores. NÃo houve diferenÃas significativas de intensidade da CH em animais KO em relaÃÃo aos controles. A modulaÃÃo da CH por talidomida e MESNA produziu reduÃÃo importante sobre a expressÃo de PTX3, enquanto a inibiÃÃo da CH por amifostina nÃo teve reduÃÃo expressiva da pentraxina. Em conjunto, estes dados apontam para um envolvimento inequÃvoco de PTX3 na fisiopatologia da inflamaÃÃo inata em modelo de CH murino com Ãntima relaÃÃo coma expressÃo de TNF-&#945; / The Hemorrhagic Cystitis (HC) is an inflammatory reaction usually associated with Cancer Chemotherapy with Oxazaphosphorines. It is an innate inflammatory response to vesical irritation by Acrolein, an hepatic metabolite of the treatment with Iphosphamide and Cyclophosphamide. The role of toll-like receptor (TLR) engagement and TNF-&#945; and IL-1&#946; expression and the involvement of iNOS and COX-2 in the pathogenesis has been well demonstrated in a murine model of HC. Recent data configure pentraxin 3 (PTX3) as an inflammatory mediator in several experimental models of innate immune response in vivo, with a straight relation with TLR engagement. Because of that, this study looks at the involvement of PTX3 in the pathogenesis of iphosphamideâinduced HC in mice. For this purpose, the mRNA to PTX3 and IL-1&#946; t was quantified by RT-PCR in groups of C57BL6 mice treated with Iphosphamide or Saline. After that, groups of transgenic and Knock-Out mice to PTX3 and its respectives wild-type controls were treated with Iphosphamide or saline with intention to measure the Bladder Wet Weight (BWW), histomorphometric scores and Immunohistochemistry and RT-PCR to PTX3, IL-1&#946;, TNF-&#945; e iNOS analysis. The transgenic mice and its controls were killed in 3h and 12h after the treatment, while the PTX3 KO and its controls were killed after 12 hours. Finally, the experimental HC was modulated by pretreatment with Talidomide, Pentoxiphiline, MESNA, Amifostine and Aminoguanidine and the bladders submitted to immunohistochemistry assay (PTX3, TNF-&#945;, IL-1&#946; and iNOS). By RT-PCR quantification, mRNA for PTX3 was expressed 70 times more in mice treated with iphosphamide than in controls, while IL-1&#946; RNAm had an expression rate of 10 times. PTX3 transgenic mice had initial reduction of the inflammatory response with less expression of PTX3 and TNF-&#945; and greater expression of iNOS. In the other hand, after 12 hours, the PTX3 transgenic mice had more inflammatory signs with superior expression of all the mediators. There was no difference between the PTX3 KO mice and its controls in the HC intensity although differences between groups were seen in cytokines expression. Talidomide and MESNA produced substantial reduction on the PTX3 expression, the same was seen to TNF-&#945;, while the amifostine marked inhibition of HC had low effect on PTX3 expression. These data as a whole, point to an unequivocal involvement of PTX3 in the pathogenesis of innate inflammatory response of HC in mice with close relation with TNF-&#945; engagement
4

Oxidative Stress, Angiogenesis and Inflammation in Normal Pregnancy and Postpartum

Palm, Maria January 2012 (has links)
The aims were to investigate oxidative stress (I), angiogenesis (II) and inflammation (III-IV) in healthy women during pregnancy and postpartum. Oxidative stress was estimated by measurement of 8-iso-PGF2α and the antioxidants α- and γ-tocopherol. The angiogenic factors PlGF, VEGF-A and the antiangiogenic factor sFlt1 were measured to estimate angiogenesis. PTX3, IL-6, TNF-α and a PGF2α metabolite were measured to estimate inflammation. Out of 52 included women, 15 had minor pregnancy complications and 37 were classified as normal. In study III data from all 52 women were used. For the other studies (I, II and IV) only data from the 37 women with normal pregnancy were used. Pregnancy was associated with increased levels of 8-iso-PGF2α with advancing gestational age. The median postpartum value corresponded to values observed in early gestation and a significant decrease was observed from late pregnancy to postpartum. Lipid-adjusted α- and γ-tocopherol levels decreased with advancing gestational age (I). PlGF increased from early pregnancy until weeks 29–30 and thereafter decreased until week 40. sFlt1 levels were relatively constant until weeks 29–30, when they increased, reaching a peak at weeks 39–40. Postpartum levels were low. The sFlt1:PlGF ratio decreased from weeks 9–12, was constantly low from weeks 19–20 to 37–38 and then increased to weeks 39–40. VEGF-A was detectable in only 8 % of the samples during pregnancy and in 64 % postpartum (II). There was a continuous increase of PTX3 as pregnancy progressed. The increase was most evident after week 31 with the highest levels just before delivery (III). IL-6 increased throughout pregnancy and remained high postpartum. No change in TNF-α could be seen with advancing gestational age or postpartum. The PGF2α metabolite levels increased throughout pregnancy and decreased postpartum (IV). In conclusion, normal pregnancy is associated with mild oxidative stress and inflammation. This might have physiological effects for normal pregnancy development. By delineating how these mediators of oxidative stress, angiogenesis and inflammation fluctuate throughout normal pregnancy and postpartum, we have established a reference for studies of these factors in pregnancy complications.
5

Characterization of proteins found in serum and sputum samples from ventilator associated pneumonia patients

Yenuga, Hima Priya 29 May 2020 (has links)
No description available.
6

Estudo do efeito do inibidor da enzima adenosina desaminase, EHNA, sobre a enterite induzida pela toxina a do Clostridium difficile em alÃa ileal isolada de camundongos / The effect of the adenosine deaminase inhibitor, EHNA, on Clostridium difficile toxin-A-induced enteritis in murine ileal loops

Ana FlÃvia Torquato de AraÃjo Junqueira 06 June 2008 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O Clostridium difficile tem como principal fator de virulÃncia a toxina A (TxA), a qual provoca inflamaÃÃo e destruiÃÃo tecidual aguda em intestinos de animais experimentais e de pacientes com a doenÃa induzida por esta bactÃria. Em locais de injÃria tecidual, adenosina à produzida em altas concentraÃÃes, onde exerce uma sÃrie de efeitos antiinflamatÃrios, limitados por sua rÃpida degradaÃÃo pela enzima adenosina desaminase. O objetivo deste trabalho foi investigar o efeito da inibiÃÃo da enzima adenosina desaminase pelo EHNA (eritro-9-(2-hidrÃxi-3-nonil)-adenina) sobre a enterite induzida pela TxA do C. difficile em alÃa ileal de camundongos. Para isto, injetamos EHNA (90 &#956;mol/kg) ou PBS i.p. 30 minutos antes da administraÃÃo de TxA (10 a 100 &#956;g) ou PBS na alÃa ileal isolada. Os animais foram sacrificados 3 horas depois da induÃÃo da enterite e as alÃas foram retiradas para estudo. As razÃes peso/comprimento da alÃa e volume de secreÃÃo/comprimento da alÃa foram calculadas e amostras de tecido foram coletadas para histopatologia, dosagem de atividade de mieloperoxidase (MPO), dosagem de TNF-&#945;, IL-1&#946; e IL-10 por ELISA, imunohistoquÃmica para TNF-&#945;, IL-1&#946;, NOS induzÃvel e PTX3, e PCR para TNF-&#945;, IL-1&#946; e PTX3. A injeÃÃo de TxA (10 a 100 &#956;g) nas alÃas ileais aumentou significativamente (p<0,05) as razÃes peso/comprimento da alÃa e volume de secreÃÃo/comprimento da alÃa com resultados consistentes a partir de 50 &#956;g. A TxA promoveu significativa (p<0,05) destruiÃÃo tecidual, edema, infiltraÃÃo de cÃlulas inflamatÃrias, aumento das citocinas TNF-&#945; e IL-1&#946;, e elevaÃÃo de iNOS e PTX3. Todos esses parÃmetros foram significativamente revertidos com o uso do EHNA (p<0,05). Em adiÃÃo, a TxA nÃo alterou os nÃveis de IL-10 em relaÃÃo ao controle, mas o prÃ-tratamento com EHNA promoveu uma elevaÃÃo nos nÃveis desta citocina. Assim, concluÃmos que na enterite induzida pela TxA em camundongos o EHNA demonstrou um potente efeito antiinflamatÃrio, reduzindo consideravelmente a lesÃo tecidual, a migraÃÃo neutrofÃlica, a expressÃo e os nÃveis de citocinas prÃinflamatÃrias (TNF-&#945;, IL-1&#946;) e produzindo um aumento nos nÃveis de IL-10. AlÃm disso, a administraÃÃo de TxA induziu um aumento na expressÃo da proteÃna PTX3 e no nÃmero de cÃlulas imunomarcadas para iNOS no tecido ileal, ambos revertidos pelo EHNA / The main factor of virulence in Clostridium difficile is toxin A (TxA), which can induce inflammation and acute tissue injury in the bowels of animals and humans affected by this organism. The high concentration of adenosine generated upon injury produces a number of antiinflammatory effects limited by rapid degradation by adenosine deaminase. The objective of this study was to determine the effect of EHNA (erythro-9-(2-hydroxy-3-nonyl)-adenine) inhibition of adenosine deaminase upon TxA-induced ileal loop enteritis in mice. EHNA (90 &#956;mol/kg) or PBS was injected i.p. 30 minutes prior to TxA (10-100 &#956;g) or PBS instillation into the ligated ileal loop. The animals were euthanized 3 hours after enteritis induction and the ileal loops were retrieved for analysis. The weight/length ratio and the secretion volume/length ratio were calculated and tissue samples were submitted to histopathological study, myeloperoxidase assay (MPO), measurement of TNF-&#945;, IL-1&#946; and IL-10 levels with ELISA, immunohistochemical tests for TNF-&#945;, IL-1&#946;, inducible NOS and PTX3, and PCR assay for TNF-&#945;, IL-1&#946; and PTX3. The instillation of TxA (10-100 &#956;g) into the ileal loop significantly increased (p<0.05) the weight/length ratio and the secretion volume/length ratio with consistent results above 50 &#956;g. TxA induced a significant amount (p<0.05) of histological damage, edema and inflammatory cell infiltration and increased the production of TNF-&#945;, IL-1&#946;, iNOS and PTX3. All changes were significantly reverted by treatment with EHNA (p<0.05). Moreover, IL-10 levels remained unchanged in animals treated with TxA, but increased in animals receiving EHNA. In conclusion, in mice with TxA-induced enteritis EHNA produced considerable antiinflammatory effects, reducing tissue injury, neutrophil migration, the expression and levels of proinflammatory cytokines (TNF-&#945; and IL-1&#946;) and producing an increase in IL-10 levels. In addition, TxA instillation increased PTX3 expression and the number of cells immunolabeled for iNOS in the ileal tissue, both of which were reverted by EHNA

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