Orientador: Angela Maria V. Campos Soares / Coorientador: Luciane Alarcão Dias-Melicio / Banca: Denise Fecchio / Banca: Dulce Helena Jardim Costantino / Resumo: O fungo Paracoccidioides brasiliensis é o agente etiológico da Paracoccidioidomicose, uma micose sistêmica, endêmica na América Latina. As células dendríticas (DCs) desempenham papel crucial na detecção de patógenos, desencadeamento de uma resposta inicial do hospedeiro, assim como na instrução da resposta imune adaptativa. Mediadores liberados pelas DCs, de uma forma autócrina, modulam as suas funções. Entre esses, destacamos as prostaglandinas e leucotrienos. Assim, avaliamos se DCs humanas produzem PGE2 e LTB4 em resposta ao fungo, a participação de receptores de reconhecimento de padrões moleculares (PRRS) nessa produção, assim como o papel modulador desses eicosanóides sobre a maturação fenotipica dessas células e a produção das citocinas IL-6, IL-10, IL-12, IL-23 e TNF-α. DCs humanas imaturas (CD14- / CD1ahigh / CD83 low) obtidas a partir da diferenciação de monócitos cultivados com GM-CSF e IL-4 (7 dias) liberaram substanciais concentrações de PGE2 e LTB4 que aumentaram significativamente, no caso da PGE2, com incubação com LPS durante 1h, 2h, 4h, 8h, 12h, 18h, 24h ou 48h. No entanto, os níveis de PGE2 e LTB4 foram significativamente inibidos após o desafio com as duas cepas do fungo. Ensaios de bloqueio dos PRRS mostraram que o processo de inibição de PGE2 envolveu o receptor de manose. Adicionalmente, ensaios de fenotipagem mostraram que após o desafio com o fungo, as DCs não alteraram o seu fenótipo de imaturas para o de células maduras. Assim, detectamos uma clara associação entre inibição da produção de PGE2 e LTB4 e a incapacidade do fungo em induzir a maturação de DCs. Ensaios utilizando PGE2 ou LTB4 exógenos confirmaram essa associação. Estas células ainda produzem altos níveis de IL-6... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The fungus Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, a systemic mycosis, endemic in Latin America. Dendritic cells (DCs) play a crucial role in the detection of pathogens, triggering an initial response from the host as well as the instruction of the adaptive immune response. Mediators released by DCs, by an autocrine way, modulate their functions. Among these, we highlight the prostaglandins and leukotrienes. We therefore assessed whether human DCs produce PGE2 and LTB4 in response to fungus, the participation of recognition receptors of molecular patterns (PRRS) in this production, as well as the modulating role of these eicosanoids on phenotypic maturation of these cells and the production of the cytokines IL-6, IL-10, IL-12, IL-23 e TNF-α. Human immature DCs (CD14-/ CD1ahigh/CD83low) derived from the differentiation of monocytes cultured with GMCSF and IL-4 (7 days) released substantial concentrations of PGE2 and LTB4 which increased significantly in the case of PGE2, with incubation with LPS for 1h, 2h, 4h, 8h, 12h, 18h, 24h or 48h. However, the levels of PGE2 and LTB4 were significantly inhibited after challenge with two different strains of the fungus. Trials have shown that blockade of PRRS process involved the inhibition of PGE2 mannose receptor. Additionally, phenotyping assays showed that after challenge with the fungus, DCs did not change their phenotype of immature cells to mature ones. Accordingly, we detected a clear association between inhibition of the production of PGE2 and LTB4 fungus and inability to induce maturation of DCs. Assays using exogenous PGE2 and LTB4 confirmed this association. These cells also produce high levels of IL-6 in response to fungus, which, however, were not associated with inhibition of the production of eisosanóides. Rather than that, these DCs do not produce... (Complete abstract click electronic access below) / Mestre

O processo de morte por apoptose pode ser dividido em duas vias: intrínseca e extrínseca. A sinalização via FAS (extrínseca) pode ocorrer independente (células Tipo I) ou dependente da mitocôndria (células Tipo II). É importante considerar que: 1) Resultados prévios mostraram que doses subletais de CHX foram capazes de sensibilizar células Tipo I e Tipo II à apoptose e de converter células Tipo II em Tipo I; 2) Um dos mecanismos envolvidos pode ser o recrutamento de FAS para as \"balsas lipídicas\"; 3) A PGE2 ativa PKA pelo aumento de cAMP via EP2 e EP4, que fosforila ezrina, envolvida nesse processo; 4) A PGE2 pode induzir apoptose em linhagens celulares e sensibilizá-las a esse processo. Assim, formulamos a hipótese de que a PGE2 poderia, assim como a CHX, sensibilizar certas células à apoptose e converter células Tipo II em Tipo I. Esse efeito não foi observado em células DO11.10 nas quais a apoptose foi induzida por CD95L solúvel e em células Tipo I e Tipo II, nas quais a apoptose foi induzida pelo anticorpo agonista anti-FAS. / The death process by apoptosis can be divided into two pathways: intrinsic and extrinsic. The signaling by FAS (extrinsic) may occur in a mitochondrial independent (Type I cells) or dependent (Type II cells) manner. It is important to consider that: 1) Previous results demonstrated that sub-lethal doses of CHX were able to sensitize type I and type II cells to apoptosis and to convert type II cells into type I; 2) One of the mechanisms involved can be FAS recruitment to \"lipid rafts\"; 3) PGE2 activates PKA by increasing cAMP via EP2 and EP4, which phosphorylates of Ezrin, involved in this process; 4) PGE2 can induces apoptosis in cell lines and can to sensitize them to this process. So, we hypothesized that PGE2 could, similarly to CHX, sensitize certain cells to apoptosis and convert type II cells into type I. This effect was not observed in DO11.10 cells in which apoptosis was induced by soluble CD95L and in type I and type II cells, in which apoptosis was induced by agonist anti-FAS antibody.

Orientador: Carlos Amilcar Parada / Texto em português e inglês / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-20T10:16:37Z (GMT). No. of bitstreams: 1 TorresChavez_KarlaElena_D.pdf: 3048246 bytes, checksum: 47a94680eba82c1f3eb36fe7add0a488 (MD5) Previous issue date: 2012 / Resumo: Os objetivos deste estudo foram: (1) Verificar se a administração local de prostaglandina E2 (PGE2) no tecido periférico aumenta o efeito anti-hiperalgésico da ativação do receptor opióide mu e se este efeito é mediado por um aumento da expressão de receptor opióide mu (2) Testar se o efeito anti-hiperalgésico da ativação do receptor opióide mu no tecido periférico está associada com a diminuição da excitabilidade das fibras-C. De acordo com o objetivo (1)... Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: The aims of this study were:(1) To verify whether local administration of E2 prostaglandin (PGE2) in peripheral tissue increases the anti-hyperalgesic effect of mu opioid receptor activation and whether this effect is mediated by an increased expression of mu opioid receptor (2) To test if the anti-hyperalgesic effect of the activation of mu opioid receptor in peripheral tissue is associated with the decrease of C-fibers excitability. According to the objective(1)... Note: The complete abstract is available with the full electronic document / Doutorado / Fisiologia Oral / Doutor em Odontologia

Le glaucome est défini par une dégénérescence du nerf optique dont le principal facteur de risque est l’hypertension oculaire due à des altérations du tissu trabéculaire. Les traitements incluent des agonistes du récepteur FP, les agonistes du récepteur EP2 pouvant également avoir des effets bénéfiques.Au cours de cette thèse, un modèle de cellules trabéculaires primaires humaines a été défini et les effets du latanoprost, un agoniste FP, et du butaprost, un agoniste EP2, ont été étudiés, d'une part, sur la survie des cellules trabéculaires, et d’autre part, sur la transition myofibroblastique. Il a été montré que l’activation du récepteur EP2 permet de protéger les cellules trabéculaires d’un stress du réticulum endoplasmique par une diminution de l’accumulation de p53 qui résulte en l’inhibition de l’expression de Puma. Enfin, le butaprost entraîne l’augmentation de l’expression de Bcl-2 et la phosphorylation de Bad qui participent à l’inhibition de l’apoptose.D’autre part, le latanoprost induit une contraction des cellules trabéculaires tandis que le butaprost inhibe la contraction induite par le TGF-B2. En revanche, les deux agonistes inhibent la déposition du collagène.En conclusion, indépendamment de leur effet hypotenseur connu, le latanoprost favoriserait l’acquisition par les cellules trabéculaires d’un phénotype contractile et l’activation du récepteur EP2 pourrait limiter le développement de la dysfonction trabéculaire en protégeant de la mort cellulaire et en favorisant une relaxation. Ces résultats suggèrent que la stimulation du récepteur EP2 pourrait limiter le développement du glaucome et serait plus favorable que les agonistes du récepteur FP. / Glaucoma is defined as an optic neuropathy whose main risk factor is ocular hypertension due to alterations of the trabecular meshwork (TM). The first-line therapies for glaucoma are agonists of the FP receptor. Agonists of the EP2 receptor could also present beneficial effects.During the thesis project, a model of primary human TM cells has been defined and the effects of latanoprost, an FP agonist, and butaprost, an EP2 agonist, have been studied on, firstly, the survival of TM cells and, secondly, on the myofibroblast transition.We have shown that activation of the EP2 receptor protects TM cells from an endoplasmic reticulum stress by a decreased accumulation of p53 which results in the inhibition of Puma transcription. Finally, butaprost mediates an increased expression of Bcl-2 and an elevation of Bad phosphorylation which contribute to protection against TM cell death.Moreover, latanoprost induces TM cell contraction while butaprost inhibits TGF-B2-dependent contraction. On the other hand, both agonists inhibit collagen.In conclusion, independently of their hypotensive effects, latanoprost would favor the acquisition by TM cells of a contractile phenotype while stimulation of EP2 receptor could limit TM dysfunction by protecting against TM cell death and relaxing the tissue. These results suggest that activation of EP2 receptor could slow down or inhibit the course of glaucoma progression and would be more favorable than the FP agonists currently used.

OBJECTIVE: Niacin, activating G-protein coupled receptor (GPR) 109A, stimulates release of vasodilatory prostaglandins (PGs) such as PGE2 which can elicit niacin-associated flushing side effects. Poly-lactic-coglycolic acid (PLGA) and poly-lactic acid (PLA) are used in nanoparticle (NP) drug delivery to reduce adverse effects and modulate drug release. Our study evaluated the in vitro effects of niacin-loaded PLGA or PLA-NPs on PGE2 expression in whole human blood as a model for niacin-induced flushing. MATERIALS AND METHODS: NPs were formulated using a solvent evaporation process and characterized by size, polydispersity, zeta potential, drug entrapment, morphology, and drug release. NP in vitro effects on PGE2 release were measured via ELISA analysis. RESULTS: PLGA-NPs demonstrated the lowest NP size (66.7 ± 0.21 nm) with the highest zeta potential and percent drug entrapment (42.00 ± 1.62 mV and 69.09 ± 0.29%, respectively) when compared to PLA-NPs (130.4 ± 0.66 nm, 27.96 ± 0.18 mV, 69.63 ± 0.03 %, respectively). In vitro release studies showed that PLGA-NPs underwent significant reductions in cumulative drug release when compared to PLA-NPs (p < 0.05). Furthermore, when compared to plain niacin, PLGA-NPs significantly reduced in vitro PGE2 release (p < 0.05). CONCLUSIONS: These results support the use of PLGA-NPs as a novel method of delivery for reducing niacin-associated flushing.

The effect or indomethacin and its vehicle on blood pressure was studied in conscious rabbits during the infusion of three vasopressors. The cyclooxygenase inhibitor raised mean arterial pressure 12 (vehicle: 3) mm Hg during norepinephrine infusion, 5 (vehicle: 0) mm Hg during angioten- sin II infusion, and 5 (vehicle: −8) mm Hg during arginine vasopressin infusion. When saline was given in place of vasopressors, indomethacin failed to alter blood pressure. Since indomethacin elevated pressure in the presence, but not the absence, of all three vasopressors, the possibility that elevation of blood pressure per se stimulates synthesis of vasodilator prostaglandins was considered. A pressor action of indomethacin was observed in ganglion-blocked animals, in which absolute blood pressure remained below normotensive levels during angiotensin II infusion. Thus, indomethacin raised arterial pressure during the infusion of norepinephrine, angiotensin II, and vasopressin, and this action was not influenced by manipulation of blood pressure. These results suggest that each vasopressor promotes prostaglandin synthesis independently to a degree sufficient to restrain its pressor action.

The contribution of vasodilator prostaglandins and kinins to blood pressure regulation was studied during the infusion of different doses of angiotensin II in conscious rabbits. Angiotensin II was infused for 60 min. in each experiment. Indomethacin, a prostaglandin synthesis inhibitor, or Trasylol, a kallikrein inhibitor, was given at the 30 min. interval. Indomethacin caused a sustained increase in blood pressure during the infusion of pressor doses of angiotensin II. The range of the mean increase after prostaglandin synthesis inhibition was 3.4 to 6.0 and 3.0 to 9.4 mm Hg at angiotensin II infusion rates of 10 and 50 ng/kg/min respectively. In contrast, indomethacin did not alter blood pressure when the peptide was administered at subpressor levels. Trasylol did not alter blood pressure during infusion of angiotensin II. These results suggest that when blood pressure is maintained at supranormal levels by angiotensin II, the pressor action is attenuated by one or more prostaglandins; an event which is not mediated or assisted by changes in kinin metabolism

No description available.

Manipulation of the reproductive tract results in increased levels of prostaglandin, which may, in turn, reduce pregnancy rates in embryo recipients. Administration of a prostaglandin inhibitor prior to embryo transfer improves pregnancy rates in cows. Embryo transfer into heifers is more difficult and often requires additional manipulation of the uterus. This study was designed to determine whether administration of the prostaglandin inhibitor, flunixin meglumine, immediately prior to embryo transfer increases pregnancy rates in heifers. Heifers (n=466) were divided into two equal groups based on BCS (range=6-7) and weight (range=256-455). Estrus was synchronized in heifers by giving two injections of prostaglandin F_2" (PGF) eleven days apart with a two day stagger between groups. Heifers in each group were watched for estrus for four days following the second PGF injection. Each heifer detected in estrus (n~389; 83%) was palpated seven days later for the presence and location of an acceptable corpus luteum; development of the reproductive tract (uterine tract score; 1=prepubertal, 5=mature tract) and amount of uterine tone (uterine tone score; l=high tone, 2=medium tone, 3=low tone) were also estimated. The 352 heifers that had an acceptable CL were paired based on day of detected estrus, body condition score, body weight, and uterine tone score. One heifer of each pair was randomly assigned to receive 10ml of flunixin meglumine (IM) just prior to embryo transfer. Time between injection until completion of embryo transfer ranged from 2-25 minutes. All heifers received a single frozen/thawed embryo transferred by one of two experienced technicians. Data collected at the time of transfer included cervix score (1-3; 1=easily penetrated, 3=difficult), ease of transfer score (1-3; l=gun easily manipulated to site of transfer, 3=difficult), embryo placement in the uterine horn (U=upper 1/3, M=middle 1/3, L=lower 1/3), and technician. Pregnancy results were obtained 90 days after transfer via rectal palpation. The logistics procedures and chi-square analysis of SAS were used for data analysis.

Acute cholecystitis is the inflammation of the gallbladder, classically caused by gall stones obstructing the cystic duct. In contrast, acalculous cholecystitis is a gallbladder inflammation occurring in the absence of cholelithiasis with a reported prevalence of 10% of all cases of acute cholecystitis. Reactive acalculous cholecystitis is an extremely rare subset of this disease that results from an adjacent inflammatory or infectious intra-abdominal process that may lead to gallbladder stasis, ischemia, and subsequent wall inflammation. Many factors have been associated with acalculous cholecystitis, including (but not limited to) hemodynamic instability, altered immunity, and biliary tree anomalies. Lack of specific signs and symptoms of this particular entity often delays the diagnosis. Herein, we present a rare case of acute, reactive, acalculous cholecystitis secondary to a perforated duodenal ulcer found incidentally during laparoscopic cholecystectomy.