A terapia com bisfosfonatos tem sido frequentemente empregada no tratamento de doenças metabólicas do osso e neoplasias malignas. O objetivo deste estudo foi avaliar através de análise histológica e histomorfométrica em cortes não descalcificados, a influência dos bisfosfonatos nitrogenados endovenosos associados ou não a dexametasona sobre a osseointegração de implantes instalados em tíbias de 27 ratos Wistar. Ácido zoledrônico e dexametasona foram administrados por via subcutânea nos animais dos grupos experimentais. Os animais foram acompanhados por 7, 14 e 28 dias. Nossos resultados mostraram que não houve falha na osseointegração em nenhum animal avaliado e que não foram observadas diferenças estatisticamente significantes entre os 3 grupos com relação à quantidade de contato entre osso e implante e presença de osso em áreas pré determinadas, nos tempos observados. No entanto nossas observações histológicas revelaram que nos animais tratados com bisfosfonatos associados ou não com dexametasona, aos 14 e 28 dias após a colocação do implante não ocorreu o fenômeno de remodelação da cortical óssea, ao contrário do grupo controle. Concluímos que a terapia com bisfosfonatos associada ou não com dexametasona não impediu a osseointegração do implante com o osso mas inibiu severamente a remodelação da cortical óssea pré existente. / Bisphosphonate therapy has been often employed in the treatment of metabolic bone diseases and malignancies. The aim of this study was to evaluate through histological and histomorphometric analysis the influence of intravenous nitrogen-containing bisphosphonates alone or combined with dexamethasone on the osseointegration of implants placed in the tibia of 27 male Wistar rats in non decalcified samples. Zoledronic acid and dexamethasone were administered through sub cutaneous injections. The animals were followed through 7, 14, and 28 days. Our results showed that there was no failure in osseointegration in any animal, and that there were no statistically significant differences among the 3 groups regarding the amount of bone-implant contact and peri-implant bone density in predetermined areas. However our histological observations revealed that animals treated with bisphosphonates, associated or not with dexamethasone, at 14 and 28 days after implant placement has not occurred the phenomenon of cortical bone remodeling, unlike control group. We conclude that bisphosphonate therapy associated or not with dexamethasone did not prevent osseointegration of the implants but severely inhibited the remodeling of pre-existing cortical bone.

A psoríase é uma doença inflamatória crônica, de alta incidência mundial, caracterizada por lesões de pele e prurido. Achados prévios do grupo mostraram que a administração i.p. do doador lento de sulfeto de hidrogênio (H2S), GYY4137, inibiu significativamente a inflamação cutânea e coceira em animais com psoríase. Assim, neste estudo avaliou-se o efeito terapêutico de uma nanodispersão tópica contendo GYY4137 sobre a psoríase induzida por imiquimode em camundongos e, comparou-se farmacologicamente o efeito do GYY4137 versus dexametasona. Animais controle ou psoríase foram tratados (1 e 2x/dia) com a nanodispersão (65 mg) contendo GYY4137, dexametasona ou apenas veículo. A aplicação tópica da nanodispersão com o GYY4137 (4%) 2x/dia, foi mais efetiva e reduziu de forma significativa o rubor, espessura, células sanguíneas totais, MPO e níveis de IL-6 e IL-1β. Os efeitos farmacológicos promovidos pelo H2S foram semelhantes aos da dexametasona, porém, a nanodispersão contendo GYY4137 demonstrou efeitos sistêmicos menos pronunciados quando comparada ao glicocorticóide. / Psoriasis is a chronic inflammatory disease, with high incidence worldwide and, characterized by skin lesions and intense itching. Previous findings of this group showed that systemic administration of the slow donor release of hydrogen sulfide (H2S), GYY4137, significantly inhibited skin inflammation and itching in mice with psoriasis. Thus, this study evaluated the therapeutic effect of a topical nanodispersion containing GYY4137 on the Imiquimod-induced psoriasis mice model and compared pharmacologically the effect of GYY4137 versus dexamethasone. Control or psoriasis animals were treated (1 and 2x/day) with nanodispersion (65 mg) containing GYY4137, dexamethasone, or just vehicle. Topical application of the nanodispersion with GYY4137 (4%) 2x/day was more effective and significantly reduced redness, thickness, total blood cells, MPO, and IL-6 and IL-1β levels. The pharmacological effects caused by H2S were similar to those of dexamethasone, however, the nanodispersion containing GYY4137 demonstrated less systemic effects when compared to glucocorticoid.

In this thesis, two potential applications of transdermal iontophoresis in the field of sports medicine were studied: (1) the local delivery of dexamethasone phosphate (Dex-Phos), a corticosteroid used to treat musculoskeletal inflammation, and (2) the extraction of systemic amino acids (AAs), potential biological markers of fatigue in athletes. The iontophoretic delivery of Dex-Phos was studied, in vitro, in order to evaluate the effects of competing ions and electroosmosis, and identify the optimal conditions for its delivery. The iontophoretic extraction of AAs from the skin was first studied in vitro, before evaluating the method in a group of human volunteers. Dex-Phos was best delivered by iontophoresis from the cathode in absence of background electrolyte in the drug solution. In this situation, the delivery of Dex-Phos is limited principally by the competition with counter-ions (mainly Na+) present subdermally and the small mobility of the drug inside the membrane. The accumulation of Cl-, released by the Ag/AgCl cathode in the drug solution during current passage, can also reduce Dex-Phos delivery. The extraction of zwitterionic AAs from the skin during iontophoresis was highly influenced by their presence in the outermost layer of the skin, the stratum corneum (SC). In the pig skin model, the amount of the AAs extracted during a short extraction period (1 hour) correlated with their abundance in the SC. Once this ‘reservoir’ was emptied (after ~3 hours of iontophoresis), the subdermal compartment could be sampled, suggesting that the method could be used to monitor systemic levels of AAs. The experiments in human volunteers revealed, however, that a 4-hour iontophoretic extraction period was insufficient to deplete the AAs SC ‘reservoir’. It follows that the method can be used to evaluate the abundance of AAs in the SC, but is unpractical for the clinical monitoring of their systemic levels.

Myocardial infarction results in tissue necrosis, leading to cell loss and ultimately to cardiac failure. Implantation of immature progenitor cells into the scar area may compensate for the cell loss and provides a new therapeutic avenue for infarct treatment. Premature myoblasts derived from skeletal muscle are one of the best candidates for this therapeutic purpose, because biopsies used for autologous cell therapy can be accessed easily, the isolated myoblasts can proliferate well in vitro, and the skeletal and cardiac muscles are structurally and functionally similar. In this study we investigated the survival and differentiation of the implanted skeletal myoblasts in the non-cryoinjured myocardium and the myocardial scar, using a syngeneic Lewis rat model. A therapeutic dose of 4x106 skeletal myoblasts/animal was implanted into the non-cryoinjured and scar tissue, and the fate of the implant was monitored at 12, 28 and 56 days after implantation by immunohistochemistry. We detected fast myosin heavy chain (fMHC) expression at each time point but significantly fewer positive cells in the scar than in the non-injured tissue. This was consistent with the staining patterns of slow myosin heavy chain (sMHC) and myogenin that overlapped with fMHC positive areas. Although the implanted myoblasts differentiated into skeletal muscle cells, they did not transdifferentiate into cardiac muscle, demonstrated by the absence of cardiac troponin I expression. During this analysis we developed a model, which could be useful to test new strategies for myoblast implantation (dosage, genetic modification, new injection technique etc.) designed to promote better engraftment of cultured myoblasts in the myocardial scar.

Submitted by Angela Maria de Oliveira (amolivei@uepg.br) on 2018-11-27T13:38:37Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Felipe Biscaia.pdf: 705544 bytes, checksum: d29d4058c2971e1453c934610a2e4d2b (MD5) / Made available in DSpace on 2018-11-27T13:38:37Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Felipe Biscaia.pdf: 705544 bytes, checksum: d29d4058c2971e1453c934610a2e4d2b (MD5) Previous issue date: 2018-08-22 / Câncer é um conjunto de doenças causadas por uma lesão gênica associada a uma expansão clonal com crescimento desproporcional. O melanoma é o câncer de pele com menor perspectiva de sobrevida e com alta capacidade de metástase. O câncer de mama é um dos mais abundantes entre as mulheres, com alta incidência de morte. Estudos relatam que todas as células do corpo humano são capazes de secretar microvesículas e, que os tecidos tumorais secretam micropartículas com mais abundancia. Essas micelas desempenham um papel importante na comunicação celular. Assim, a comunicação entre as células tumorais possui uma função essencial para o desenvolvimento do câncer. Neste trabalho, as linhagens de melanoma B16F10 e adenocarcinoma 4T1 foram cultivadas e submetidas ao tratamento dos fármacos Dexametasona e tamoxifeno, bem como microvesículas extraídas dos sobrenadante de B16F10 tratado com dexametasona. Como resultados, observamos redução da viabilidade celular de ambas as linhagens ocasionada pelos três tratamentos isolados, assim como pelos tratamentos combinados do compostos utilizados. Os fármacos e as microvesículas desencadearam efeitos citotóxicos sobre as linhagens tumorais, mostrando-se potenciais alternativas para tratamento. / Cancer is a set of diseases caused by a simple gene injury associated with a clonal expansion with disproportionate growth. Melanoma is a skin cancer with a lower survival prospect and high metastatic capacity. Breast cancer is one of the most abundant among women, with a high incidence of death. Several studies report that all human cells are able to secrete microvesicles, and that tumor tissues secrete microparticles with high abundance. These micelles play an important role in cellular communication. Thus, communication between tumor cells has an essential function for the development of cancer. In this work, the B16F10 melanoma and 4T1 adenocarcinoma cell lines were cultured and treated with the drugs Dexamethasone and tamoxifen, as well as microvesicles extracted from the B16F10 supernatant treated with dexamethasone. The results shows a reduction in the cell viability of both strains caused by the three isolated treatments, as well as by the combined treatments of the compounds used. Drugs and microvesicles triggered cytotoxic effects on tumor lines, showing potential treatment alternatives.

A estrongiloidíase é uma parasitose intestinal sendo considerada a quarta maior causada por nematódeos. O mecanismo de defesa contra a estrongiloidíase é mediada pela ativação de células de perfil Th2, que amplificam a resposta celular através da secreção de mediadores inflamatórios. O que faz da estrongiloidíase um grave problema de saúde pública, é o desenvolvimento da hiperinfecção, principalmente devido ao uso de glicocorticóides, onde ocorre aumento do número de larvas e fêmeas que se disseminam por todo organismo. Estudos demonstraram que algumas infecções helmínticas têm sido acompanhadas por hipertrofia e hipercontratillidade da musculatura intestinal, via JAK-STAT 6. Entretanto pouco se sabe sobre a influência desta via nas alterações da parede muscular do duodeno durante infecção pelo Strongyloides venezuelensis. O presente trabalho objetivou investigar as alterações morfológicas, imunológicas e patológicas da musculatura lisa intestinal que ocorrem em decorrência da infecção experimental pelo S. venezuelensis, bem como a interferência do tratamento com Dexametasona e o papel da via JAK - STAT 6 neste processo. Ratos Wistar foram inoculados com larvas de S. venezuelensis, tratados com dexametasona e sacrificados nos dias 5, 7, 14 e 21. Foram realizadas diversas colorações com a finalidade de quantificar as fêmeas adultas no duodeno, realizar morfometria da musculatura duodenal, quantificar eosinófilos e células caliciformes. Foi realizada análise da expressão gênica do gene STAT 6. Nossos resultados mostraram hiperplasia das células caliciformes, infiltrado eosinofílico e espessamento da musculatura lisa duodenal. Houve aumento na expressão de STAT 6 nos animais infectados. O tratamento com a Dexametasona inibiu drasticamente estas alterações. Entretanto o número de parasitas foi significativamente maior nos ratos infectados tratados quando comparados aos infectados. As alterações intestinais durante a infecção ocorreram na tentativa de expulsar o parasita e resolução da infecção. Contudo, a inibição deste processo provocada pela Dexametasona possivelmente retardou ou impediu a resolução da infecção. / Strongyloidiasis is an intestinal parasitosis with an obligatory pulmonary cycle, which represents the fourth largest parasitosis caused by nematodes. The mechanism of defense against strongyloidiasis is mediated by activation of Th2 cells, which amplify the cellular response through the secretion of inflammatory mediators. Strongyloidiasis is a serious public health problem due the development of hyperinfection, due to the use of glucocorticoids, where the number of worms and females increases, and disseminate to other organs. Studies have shown that some helminth infections have been accompanied by hypertrophy of intestinal muscles and hypercontractility, JAK-STAT 6 pathway. However little has been reported about on the influence of JAK-STAT 6 pathway in changes of the muscular wall of the duodenum during Strongyloides venezuelensis infection. The aim of this study was to identify the morphological, immunological and pathological changes of the intestinal smooth muscle during Strongyloides venezuelensis in Wistar rats and to determine the effects of Dexamethasone treatment and role of JAK-STAT 6 pathway in these process. Wistar rats were inoculated with S. venezuelensis larvae, treated with dexamethasone and killed at 5, 7, 14 and 21 days. Morphological and morphometric analyzes with routine stains to quantify globet cells, eosinophils and measure the circular and longitudinal layers of duodenal smooth muscle. Performed gene expression analysis of STAT 6. Goblet cell hyperplasia and increased of intestine smooth muscle wall thickness and eosinophils levels were elevated throughout the course of the infection. Moreover, an increase in the expression of STAT 6 in infected animals. The morphological findings and the immunomodulatory response to the infection were drastically reduced in dexamethasone-treated rats. However, the number of worms was significantly higher on infected and treated rats with Dexamethasone compared to just infected ones. The intestinal changes during infection ocurred in an attempt of expel the parasite and elucidate the infection. Although, the inhibition of the process caused by Dexamethasone possibly delay or prevent the resolution of infection

Tang Yin Nei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves xv-xxv). / Abstracts in English and Chinese. / ACKNOWLEDGEMENT --- p.i / ABBREVIATIONS --- p.ii-iii / INDEX FOR FIGURES --- p.iv-v / INDEX FOR TABLES --- p.vi / ABSTRACT (Chinese and English) --- p.vii-xi / TABLE OF CONTENTS --- p.xii-xiv / Chapter CHAPTER I 226}0ؤ --- INTRODUCTION --- p.1 / Chapter 1.1 --- Background --- p.2 / Chapter 1.2 --- Tendon / Chapter 1.2.1 --- Structure and function --- p.3 / Chapter 1.2.2 --- Tendon fibroblast --- p.6 / Chapter 1.2.3 --- Components of the extracellular matrix --- p.7 / Chapter 1.2.3.1 --- Collagen --- p.8 / Chapter 1.2.3.2 --- Proteoglycan --- p.9 / Chapter 1.2.3.3 --- Non-collagenous structural glycoprotein --- p.10 / Chapter 1.3 --- Inflammation disorders of tendon / Chapter 1.3.1 --- Inflammation --- p.11 / Chapter 1.3.2 --- Treatment --- p.12 / Chapter 1.3.2.1 --- Glucocorticoid as an anti-inflammatory agent --- p.12 / Chapter 1.3.2.2 --- Dexamethasone --- p.14 / Chapter 1.3.3 --- Clinical occurrence of tendon rupture --- p.15 / Chapter 1.3.4 --- Animal research related to glucocorticoids and tendon rupture --- p.18 / Chapter 1.4 --- Platelet-derived growth factor isoform B (PDGFBB) / Chapter 1.4.1 --- Structure and function --- p.21 / Chapter 1.4.2 --- PDGFbb effects on connective tissue --- p.22 / Chapter CHAPTER II 226}0ؤ --- AIM OF THE STUDY --- p.23 / Chapter 2.1 --- Limitations of the past researches --- p.24 / Chapter 2.2 --- Hypothesis of this study --- p.25 / Chapter 2.3 --- Objectives --- p.26 / Chapter 2.4 --- Long term significance --- p.26 / Chapter CHAPTER III 226}0ؤ --- METHODOLOGY --- p.27 / Chapter 3.1 --- Chemicals and materials used / Chapter 3.1.1 --- Chemicals --- p.28 / Chapter 3.1.2 --- Materials --- p.28 / Chapter 3.2 --- Specimen collection and preparation / Chapter 3.2.1 --- Collection --- p.29 / Chapter 3.2.2 --- Preparation and isolation --- p.30 / Chapter 3.2.3 --- Cell culture --- p.31 / Chapter 3.3 --- Reagent preparation / Chapter 3.3.1 --- Charcoal-stripped serum --- p.32 / Chapter 3.3.2 --- Phenol-red free DMEM --- p.33 / Chapter 3.3.3 --- MTT --- p.33 / Chapter 3.3.4 --- Dexamethasone --- p.34 / Chapter 3.3.5 --- PDGFbb --- p.34 / Chapter 3.3.6 --- Trypan blue --- p.35 / Chapter 3.3.7 --- TCA/Tannic acid --- p.35 / Chapter 3.3.8 --- Collagenase buffer --- p.35 / Chapter 3.4 --- Morphology / Chapter 3.4.1 --- Inverted phase contrast light microscopy --- p.36 / Chapter 3.4.2 --- Scanning electron microscopy --- p.36 / Chapter 3.5 --- Biological assays / Chapter 3.5.1 --- "MTT (3-[4,5-Dimethylthiazol-2-yl]2,5-diphenyltetrazolium bromide) assay" --- p.38 / Chapter 3.5.1.1 --- Correlation between MTT assay and trypan blue dye method --- p.38 / Chapter 3.5.1.2 --- Growth kinetics for tendon fibroblasts --- p.41 / Chapter 3.5.1.3 --- Cell viability --- p.43 / Chapter 3.5.2 --- Brdu (5-bromo-2'-deoxyuridine) assay --- p.44 / Chapter 3.5.3 --- Flow cytometry --- p.45 / Chapter 3.5.4 --- Apoptosis --- p.47 / Chapter 3.5.5 --- 3H-Proline incorporation assay --- p.48 / Chapter 3.5.6 --- 35Sulfate incorporation assay --- p.51 / Chapter 3.5.7 --- Immunocytochemistry (PDGF-β receptor) --- p.54 / Chapter 3.6 --- Statistical analysis / Chapter 3.6.1 --- Dose-response curve of dexamethasone on cell viability and proliferation --- p.55 / Chapter 3.6.2 --- Comparison among various treatments of fibroblasts --- p.55 / Chapter CHAPTER I´Vؤ --- RESULTS --- p.56 / Chapter 4.1 --- In vitro effect of dexamethasone on rat tendon fibroblasts / Chapter 4.1.1 --- Viable cell number between two sexes --- p.57 / Chapter 4.2 --- In vitro effect of dexamethasone and PDGFBB on human tendon fibroblasts / Chapter 4.2.1 --- Gross morphology --- p.58 / Chapter 4.2.2 --- Cell cycle --- p.60 / Chapter 4.2.3 --- Apoptosis --- p.61 / Chapter 4.2.4 --- Viable cell number / Chapter 4.2.4.1 --- Effect of dexamethasone --- p.62 / Chapter 4.2.4.2 --- Effect of PDGFBB --- p.63 / Chapter 4.2.5 --- Cell proliferation / Chapter 4.2.5.1 --- Effect of dexamethasone --- p.65 / Chapter 4.2.5.2 --- Effect of PDGFbb --- p.67 / Chapter 4.2.6 --- Collagen synthesis --- p.68 / Chapter 4.2.7 --- Proteoglycan synthesis --- p.72 / Chapter 4.2.8 --- PDGF-rβ expression --- p.74 / Chapter CHAPTER V 226}0ؤ --- DISCUSSION --- p.75 / Chapter 5.1 --- Dexamethasone and PDGFBB induced change of cell morphology --- p.77 / Chapter 5.2 --- Dexamethasone retarded cell growth of human tendon fibroblast --- p.80 / Chapter 5.3 --- Dexamethasone inhibited collagen synthesis --- p.82 / Chapter 5.4 --- Dexamethasone inhibited proteoglycan synthesis --- p.86 / Chapter 5.5 --- PDGFbb could counteract the inhibitory effects of dexamethasone --- p.88 / Chapter 5.6 --- Expression of PDGF-(3 receptor is regulated by dexamethasone and PDGFBB --- p.90 / Chapter 5.7 --- Limitations of this study / Chapter 5.7.1 --- Not enough sample to differentiate different between two sexes --- p.92 / Chapter 5.7.2 --- Small sample size and few assays --- p.92 / Chapter 5.7.3 --- Limitations of the cell culture model --- p.93 / Chapter 5.7.4 --- Difficult to further in vivo study on human --- p.93 / Chapter 5.8 --- Contributions of this study / Chapter 5.8.1 --- Improve the limitation of the past research --- p.94 / Chapter 5.8.1.1 --- Human tendon specimen --- p.94 / Chapter 5.8.1.2 --- In vitro system --- p.94 / Chapter 5.8.2 --- Understand the effect of dexmaethasone on human tendon fibroblasts --- p.95 / Chapter 5.8.3 --- Counteract the deleterious effects of dexamethasone by PDGFBB --- p.95 / Chapter CHAPTER VÍؤ --- CONCLUSION & FUTURE STUDY --- p.96 / Chapter 6.1 --- Conclusion --- p.97 / Chapter 6.2 --- Future study --- p.98 / Chapter 6.2.1 --- Study the balance between matrix synthesis and degradation --- p.98 / Chapter 6.2.2 --- Determine collagen typing --- p.99 / Chapter 6.2.3 --- Further explore the effect of glucocorticoid in organ culture model --- p.100 / Chapter 6.2.4 --- Investigate molecular mechanism of dexamethasone and PDGFBB --- p.100 / REFERENCES --- p.xv-xxv / APPENDIX --- p.xxvi

A estrongiloidíase é uma parasitose intestinal sendo considerada a quarta maior causada por nematódeos. O mecanismo de defesa contra a estrongiloidíase é mediada pela ativação de células de perfil Th2, que amplificam a resposta celular através da secreção de mediadores inflamatórios. O que faz da estrongiloidíase um grave problema de saúde pública, é o desenvolvimento da hiperinfecção, principalmente devido ao uso de glicocorticóides, onde ocorre aumento do número de larvas e fêmeas que se disseminam por todo organismo. Estudos demonstraram que algumas infecções helmínticas têm sido acompanhadas por hipertrofia e hipercontratillidade da musculatura intestinal, via JAK-STAT 6. Entretanto pouco se sabe sobre a influência desta via nas alterações da parede muscular do duodeno durante infecção pelo Strongyloides venezuelensis. O presente trabalho objetivou investigar as alterações morfológicas, imunológicas e patológicas da musculatura lisa intestinal que ocorrem em decorrência da infecção experimental pelo S. venezuelensis, bem como a interferência do tratamento com Dexametasona e o papel da via JAK - STAT 6 neste processo. Ratos Wistar foram inoculados com larvas de S. venezuelensis, tratados com dexametasona e sacrificados nos dias 5, 7, 14 e 21. Foram realizadas diversas colorações com a finalidade de quantificar as fêmeas adultas no duodeno, realizar morfometria da musculatura duodenal, quantificar eosinófilos e células caliciformes. Foi realizada análise da expressão gênica do gene STAT 6. Nossos resultados mostraram hiperplasia das células caliciformes, infiltrado eosinofílico e espessamento da musculatura lisa duodenal. Houve aumento na expressão de STAT 6 nos animais infectados. O tratamento com a Dexametasona inibiu drasticamente estas alterações. Entretanto o número de parasitas foi significativamente maior nos ratos infectados tratados quando comparados aos infectados. As alterações intestinais durante a infecção ocorreram na tentativa de expulsar o parasita e resolução da infecção. Contudo, a inibição deste processo provocada pela Dexametasona possivelmente retardou ou impediu a resolução da infecção. / Strongyloidiasis is an intestinal parasitosis with an obligatory pulmonary cycle, which represents the fourth largest parasitosis caused by nematodes. The mechanism of defense against strongyloidiasis is mediated by activation of Th2 cells, which amplify the cellular response through the secretion of inflammatory mediators. Strongyloidiasis is a serious public health problem due the development of hyperinfection, due to the use of glucocorticoids, where the number of worms and females increases, and disseminate to other organs. Studies have shown that some helminth infections have been accompanied by hypertrophy of intestinal muscles and hypercontractility, JAK-STAT 6 pathway. However little has been reported about on the influence of JAK-STAT 6 pathway in changes of the muscular wall of the duodenum during Strongyloides venezuelensis infection. The aim of this study was to identify the morphological, immunological and pathological changes of the intestinal smooth muscle during Strongyloides venezuelensis in Wistar rats and to determine the effects of Dexamethasone treatment and role of JAK-STAT 6 pathway in these process. Wistar rats were inoculated with S. venezuelensis larvae, treated with dexamethasone and killed at 5, 7, 14 and 21 days. Morphological and morphometric analyzes with routine stains to quantify globet cells, eosinophils and measure the circular and longitudinal layers of duodenal smooth muscle. Performed gene expression analysis of STAT 6. Goblet cell hyperplasia and increased of intestine smooth muscle wall thickness and eosinophils levels were elevated throughout the course of the infection. Moreover, an increase in the expression of STAT 6 in infected animals. The morphological findings and the immunomodulatory response to the infection were drastically reduced in dexamethasone-treated rats. However, the number of worms was significantly higher on infected and treated rats with Dexamethasone compared to just infected ones. The intestinal changes during infection ocurred in an attempt of expel the parasite and elucidate the infection. Although, the inhibition of the process caused by Dexamethasone possibly delay or prevent the resolution of infection

A terapia com bisfosfonatos tem sido frequentemente empregada no tratamento de doenças metabólicas do osso e neoplasias malignas. O objetivo deste estudo foi avaliar através de análise histológica e histomorfométrica em cortes não descalcificados, a influência dos bisfosfonatos nitrogenados endovenosos associados ou não a dexametasona sobre a osseointegração de implantes instalados em tíbias de 27 ratos Wistar. Ácido zoledrônico e dexametasona foram administrados por via subcutânea nos animais dos grupos experimentais. Os animais foram acompanhados por 7, 14 e 28 dias. Nossos resultados mostraram que não houve falha na osseointegração em nenhum animal avaliado e que não foram observadas diferenças estatisticamente significantes entre os 3 grupos com relação à quantidade de contato entre osso e implante e presença de osso em áreas pré determinadas, nos tempos observados. No entanto nossas observações histológicas revelaram que nos animais tratados com bisfosfonatos associados ou não com dexametasona, aos 14 e 28 dias após a colocação do implante não ocorreu o fenômeno de remodelação da cortical óssea, ao contrário do grupo controle. Concluímos que a terapia com bisfosfonatos associada ou não com dexametasona não impediu a osseointegração do implante com o osso mas inibiu severamente a remodelação da cortical óssea pré existente. / Bisphosphonate therapy has been often employed in the treatment of metabolic bone diseases and malignancies. The aim of this study was to evaluate through histological and histomorphometric analysis the influence of intravenous nitrogen-containing bisphosphonates alone or combined with dexamethasone on the osseointegration of implants placed in the tibia of 27 male Wistar rats in non decalcified samples. Zoledronic acid and dexamethasone were administered through sub cutaneous injections. The animals were followed through 7, 14, and 28 days. Our results showed that there was no failure in osseointegration in any animal, and that there were no statistically significant differences among the 3 groups regarding the amount of bone-implant contact and peri-implant bone density in predetermined areas. However our histological observations revealed that animals treated with bisphosphonates, associated or not with dexamethasone, at 14 and 28 days after implant placement has not occurred the phenomenon of cortical bone remodeling, unlike control group. We conclude that bisphosphonate therapy associated or not with dexamethasone did not prevent osseointegration of the implants but severely inhibited the remodeling of pre-existing cortical bone.

Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-08-24T16:53:19Z No. of bitstreams: 1 ThiareBraga.pdf: 2583243 bytes, checksum: c6622c8e436020170dbf4d6da63bb75e (MD5) / Made available in DSpace on 2017-08-24T16:53:19Z (GMT). No. of bitstreams: 1 ThiareBraga.pdf: 2583243 bytes, checksum: c6622c8e436020170dbf4d6da63bb75e (MD5) Previous issue date: 2017-05-08 / Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão (FAPEMA) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Propolis produced by bees Apis mellifera is a resinous balsamic material used to protect the hive against fungi, bacteria, viruses and insects. Among the antimicrobial activities of propolis already proven, the antifungal action observed in strains of Candida albicans, commensal fungus of the oro-gastrointestinal tract and skin, associated with opportunistic infections, local or systemic, especially in immunosuppressed patients, are highlighted. The objective of this study was to evaluate the effect of treatment with standardized extract of propolis on systemic infection caused by C. albicans in immunosuppressed mice. Initially the C57Bl/ 6 mice were immunosuppressed with dexamethasone (3mg / kg) for one week and, on the eighth day, were infected intraperitoneally with C. albicans blastopores (2x106). After 24 hours of infection, the daily treatment of the animals with propolis at the doses of 10 and 100 mg/kg was initiated for 15 days intraperitoneally. Immunosuppression with dexamethasone was maintained for all the analysis. At the end of the 15 days, all the animals treated with propolis at the dose of 100 mg/kg were kept alive, while all the animals from the other groups had already died. From then on, it was possible to investigate possible immunological mechanisms to explain this effect. For this, the same protocol of immunosuppression and infection described above was repeated, however, the treatment was performed in a single application of propolis at a dose of 100 mg/kg, 24 hours after infection and the tests were performed 24 hours after this treatment. Treatment with propolis reduced the colony forming units in the peritoneum and spleen. In addition, propolis reversed dexamethasone-induced immunosuppression, increasing the number of circulating leukocytes, mainly neutrophils, proliferation of splenocytes, recruitment of leukocytes to the site of infection and increase of CD4+ T lymphocytes. Regarding the inflammatory mediators, it was observed that the treatment with propolis induced the increase of the ex vivo production of nitric oxide by peritoneal cells and the reduction of plasmatic inflammatory cytokines (IL-6 and TNF-α). Finally, in an in vitro experiment, peritoneal macrophages were treated with dexamethasone (4 μg/mL), for 48 hours, and then treated with propolis (100 μg/mL) for 12 hours. Then, cells were incubated with C. albicans for 1 hour. In this assay, it was observed that propolis increased phagocytosis, without, however, altering Dectin-1 and Mannose receptor expression. In conclusion, the standardized extract of propolis increased life expectancy and reduced C. albicans dissemination in immunosuppressed mice. Such effects are probably due to its ability to reverse dexamethasone-induced immunosuppression, recruit and activate effector immune cells to the site of infection, and reduce serum inflammatory cytokines, thereby reducing the progression of the deleterious aspects of systemic candidemia. / A própolis produzida pelas abelhas Apis melífera é um material balsâmico resinoso, utilizado para a proteção da colmeia contra fungos, bactérias, vírus e insetos. Dentre as atividades antimicrobianas da própolis já comprovadas, destaca-se: a ação antifúngica observada em cepas de Candida albicans, fungo comensal do trato oro-gastrointestinal e da pele, associado a infecções oportunistas, locais ou sistêmicas, em especial, em pacientes imunossuprimidos. O objetivo deste trabalho foi avaliar o efeito do tratamento com Extrato Padronizado de Própolis (EPP-AF®) na infecção sistêmica ocasionada por C. albicans em camundongos imunossuprimidos. Inicialmente, os camundongos C57Bl/6 foram imunossuprimidos com dexametasona (3mg/kg) durante uma semana e, no oitavo dia foram infectados, por via intraperitoneal, com blastóporos de C. albicans (2x106). Após 24 horas da infecção, foi iniciado o tratamento diário dos animais com própolis nas doses de 10 e 100mg/Kg, durante 15 dias, por via intraperitoneal. A imunossupressão com dexametasona foi mantida ao longo de toda a análise. Ao final dos 15 dias, observou-se que todos os animais tratados com própolis na dose de 100mg/Kg, mantinham-se vivos, enquanto todos os animais dos demais grupos já haviam morrido. A partir daí, passou-se a investigar possíveis mecanismos imunológicos que explicassem esse efeito. Para isto, foi repetido o mesmo protocolo de imunossupressão e infecção descritos acima, entretanto, o tratamento foi realizado em uma única aplicação de própolis na dose de 100mg/Kg, 24 horas após a infecção e os ensaios foram realizados 24 horas após esse tratamento. O tratamento com própolis reduziu as unidades formadoras de colônia no peritônio e no baço. Além disso, a própolis reverteu a imunossupressão induzida pela dexametasona, aumentando o número de leucócitos circulantes, principalmente, neutrófilos, a proliferação de esplenócitos, o recrutamento de leucócitos ao sítio da infecção e aumento de linfócitos T CD4+. Em relação aos mediadores inflamatórios, foi observado que o tratamento com própolis induziu o aumento da produção ex vivo de óxido nítrico por células peritoneais e a diminuição das citocinas inflamatórias (IL-6 e TNF-α) plasmáticas. Finalmente, em experimento in vitro, macrófagos peritoneais foram tratados com dexametasona (4µg/mL), por 48 horas, e, em seguida, tratados com própolis (100µg/mL), durante 12 horas. Ao final, as células foram incubadas com C. albicans por 1 hora. Neste ensaio, foi observado que a própolis aumentou a fagocitose, sem, no entanto, alterar a expressão proteica de Dectina-1 e Receptor de manose. Em conclusão, o extrato padronizado de própolis aumentou a expectativa de vida e reduziu a disseminação de C. albicans em camundongos imunosuprimidos. Tais efeitos, provavelmente devem-se a sua capacidade de reverter a imunossupressão induzida pela dexametasona, recrutando e ativando células imunes inatas para o sítio da infecção, além de reduzir as citocinas inflamatórias séricas, diminuindo, assim, a progressão dos aspectos deletérios da candidemia sistêmica.