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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.
91

Contribuição da imagem tridimensional para o diagnóstico do cisto de retenção mucoso do seio maxilar / Three-dimensional Image Contributing to the diagnosis of Mucous Retention cyst in Maxillary Sinus

RODRIGUES, Cleomar Donizeth 31 May 2011 (has links)
Made available in DSpace on 2014-07-29T15:25:17Z (GMT). No. of bitstreams: 1 TESE CLEOMAR D RODRIGUES -Cisto Ret Mucoso Seio Maxilar.pdf: 1752210 bytes, checksum: 164b291567764c89587221e7d462d819 (MD5) Previous issue date: 2011-05-31 / Objective: To detect the mucous retention cyst of maxillary sinus (MRCMS) through panoramic radiography and cone beam computed tomography (CBCT). Methods: Six thousand panoramic radiographs were selected from digital database for diagnostic analysis of MRCMS. We detected suggestive images of MRCMS in 185 radiographs of patients who were located and invited to return to control. Thirty patients returned for the realization of panoramic radiography for control between 6 and 46 months. Given the presence of MRCMS by radiographic control we performed the CBCT for a better evaluation of the maxillary sinus. Cysts were measured and compared through the images of two methods. The Wilcoxon, Spearman and Kolmorogov-Smirnov tests were used for statistical analysis. The level of significance was set at 5%. Results: There was statistically significant difference between the methods for detection of MRCMS (p <0.05); 23 MRCMS detected by panoramic radiography control were confirmed by CBCT, however, 5 MRCMS detected in CBCT images were not identified by panoramic radiographs. Eight MRCMS detected by X-ray control were not confirmed by CBCT. The discrepancy of extent of MRCMS between images of initial panoramic radiographs and control ones for the CBCT were not statistically significant (p = 0.617 and p = 0.626, respectively) as well as the correlation between time and discrepancy of extent of MRCMS (r = -0.16, p = 0.381). Conclusion: The cone beam computed tomography examination provides more accurate detection of MRCMS than panoramic radiography / Objetivos: Detectar o cisto de retenção mucoso do seio maxilar (CRMSM) por meio da radiografia panorâmica e tomografia computadorizada de feixe cônico (TCFC). Metodologia: Seis mil radiografias panorâmicas foram selecionadas do banco digital de dados para análise de diagnóstico de CRMSM. Foram detectadas imagens sugestivas de CRMSM em 185 radiografias, cujos pacientes foram localizados e convidados a retornar para controle. Trinta indivíduos retornaram para a realização de radiografia panorâmica para controle entre 6 e 46 meses. Constatada a presença do CRMSM pelo controle radiográfico realizava-se a TCFC, para uma melhor avaliação do seio maxilar. Cistos foram mensurados e comparados por meio das imagens dos dois métodos. Os testes de Wilcoxon, de Spearman e Kolmorogov-Smirnov foram utilizados para análise estatística. O Nível de significância estabelecido foi de 5%. Resultados: Foi observada diferença estatisticamente significante entre os métodos para detecção dos CRMSM (p<0,05); 23 CRMSM diagnosticados por meio da radiografia panorâmica controle foram confirmados por TCFC, no entanto, 5 CRMSM detectados em TCFC não foram identificados pelas imagens de radiografias panorâmicas. Oito CRMSM detectados pelo controle radiográfico não foram confirmados pela TCFC. A discrepância da extensão do CRMSM entre as imagens das radiografias panorâmicas inicial e controle e da panorâmica controle e TCFC não foram estatisticamente significantes (p=0,617 e p=0,626, respectivamente), bem como a correlação entre tempo e a discrepância da extensão dos CRMSM (r= -0,16 e p= 0,381). Conclusão: O exame por tomografia computadorizada do feixe cônico apresentou maior potencial de detecção de CRMSM que a radiografia panorâmica.
92

Indução de tolerância nasal com colágeno tipo V em modelo experimental de esclerodermia / Collagen V- induced nasal tolerance in scleroderma experimental model

Ana Paula Pereira Velosa 08 May 2007 (has links)
Objetivo: Verificar o remodelamento da pele e produção de anticorpos em modelo experimental de esclerodermia em coelhos, após indução de tolerância nasal com colágeno tipo V. Métodos: Coelhas Nova Zelândia (N=12) foram imunizadas com 1mg/ml de colágeno V (Col V) em adjuvante completo de Freund e dois reforços com adjuvante incompleto de Freund. Seis coelhas imunizadas receberam uma dose diária de 25ug de Col V, iniciado via nasal (grupo tolerado) 150 dias do começo das imunizações e seis animais foram somente imunizadas (grupo imunizado). Um grupo imunizado com adjuvante de Freund serviu como controle. Biopsias de pele foram coletadas em 0, 75, 120, 150 e 210 dias e coradas pelo H&E, tricrômico de Masson e Sírius red para analise morfológica e morfométrica. Os colágenos I, III e V, além de TGFbeta e PDGF foram imunomarcados por imunofluorescência. Os soros dos animais foram coletados em 0, 150 e 210 dias para determinar anticorpos anti-colágenos I, III, IV e V e anti-nucleares. Resultados: Os animais imunizados mostraram progressivo decréscimo da derme papilar, atrofia de anexos, aumento no depósito dos colágenos I, III e V e aumento da expressão de TGFbeta e PDGF. Os tolerados apresentaram aumento dos anexos cutâneos e significante diminuição no depósito dos colágenos I, III e V, TGFbeta e PDGF. O grupo de imunizados e de tolerados apresentaram anticorpos anti-colágenos III e IV e antinucleares. Conclusões: A indução de tolerância nasal com Col V diminuiu o remodelamento da pele observado no modelo experimental de esclerodermia e inibiu a síntese de citocinas fibrogênicas. Portanto, a tolerância nasal com Col V pode ser uma opção terapêutica promissora para o controle do remodelamento cutâneo em pacientes com esclerodermia. / Objective: Our aim was to verify the skin remodeling and antibody production in experimental model of scleroderma in rabbits, after induction of tolerance by daily nasal administration of human type V collagen (Col V). Methods: Female New Zealand rabbits (N=12) were immunized with 1mg/ml of Col V in complete Freund\'s adjuvant, followed by more two boosters in incomplete Freund\'s adjuvant. Six immunized rabbits received daily nasal administrating of 25ug of Col V (tolerated group), started 150 days after the first immunization, and the others animals (N=6) were only immunized (immunized group). Finally a group of rabbits immunized with Freund\'s adjuvant served as control. Skin biopsies were collected at 0, 75, 120, 150 and 210 days, and stained with H&E, Masson\'s trichrome and Sirius red for morphological and morphometric analysis. Types I, III and V collagen, TGFbeta and PDGF were immunostained by immunofluorescence. The sera of animals were colleted at 0, 150 and 210 days to determine anti types I, III, IV and V collagen and antinuclear antibodies. Results: The immunized animals showed progressive decrease of papillary dermis, appendages atrophy, increase of types I, III and V collagen deposition and increased expression of TGF-beta and PDGF. The tolerated rabbits presented increase of cutaneous appendages and significant decrease of types I, III and V and TGF-beta and PDGF. Both immunized and tolerated rabbits presented anti types III and IV antibodies and antinuclear antibodies. Conclusions: Col V nasal tolerance reduced skin remodeling in experimental model of scleroderma and inhibited synthesis of fibrotic cytokines. Therefore, the nasal tolerance with type V collagen can be a promising therapeutic option to control the skin remodeling in patients with scleroderma.
93

Explorations optiques multimodales et multiéchelles non invasives appliquées au revêtement cutanéomuqueux , étendues à l'appareil oculaire antérieur / Non-invasive multi-modal and multi-scales optical examinations, applied to the skin and mucosae extended to the anterior ocular apparatus

Perrot, Jean-Luc 09 May 2017 (has links)
Après une introduction brève de l’historique de l’imagerie dermatologique non invasive, ce travail est divisé 3 parties. 1) Présentation d’un projet de développement d’un tomographe à cohérence optique miniaturisé, peu onéreu devant permettre une diffusion de cette technique aux dermatologues exerçant en dehors des hôpitaux. Il s’agi d’un projet ANR DOCT-VCSEL Portable Optical Coherence Tomography with MEMS-VCSEL swept- sources for skin analysis ANR 2015 / Défi sociétal « Vie, Santé et Bien-Etre » Axe 13 « Technologies pour la santé » 2) Présentation d’un projet dont le but est l’identification de lésions cutanées cancéreuses au moyen d’un nouvel OCT haute définition développé par la société DAMAE, issue de l’Institut supérieur d’Optique de Palaiseau. Il s’agit d’un dispositif qui sera dans un premier temps réservé aux centre d’excellence en imagerie dermatologique. 3) la reprise des 52 publications ayant trait à l’imagerie cutanée auxquelles j’ai participé et référencées dans les bases de données internationales au 31 décembre 2016. Ce travail couvre l’ensemble de l’imagerie non invasive dermatologique moderne et aborde des sujets qui n’avaient jamais été étudié de la sorte. Notamment les muqueuses et l’appareil oculaire antérieur mais aussi l’identification par microscopie confocale des marge chirurgicales ou l’association microscopie confocale spectrométrie Raman / After a brief introduction to the history of non-invasive dermatological imaging, this work is divided into 3 parts. 1) Presentation of a project for the development of a low-cost miniaturized optical coherence tomograph to allow dissemination of this technique to dermatologists practicing outside hospitals. This is an ANR project: DOCT-VCSEL Portable Optical Coherence Tomography with MEMS-VCSEL swept-sources for skin analysis ANR 2015 / Societal Challenge "Life, Health and Welfare" Axis 13 “Technologies for Health" 2) Presentation of a project whose goal is the identification of cancer skin lesions by means of a new high definition OCT developed by the company DAMAE, resulting from the Higher Institute of Optics of Palaiseau. It is a device that will initially be reserved for centers of excellence in dermatological imaging. 3) Presentation of 52 publications related to skin imaging, in which I participated, and referenced in the international databases as of December 31, 2016. This work covers all modern dermatological non-invasive imaging and addresses Subjects that had never been studied in this way. Notably the mucous membranes and the anterior ocular apparatus but also the identification by confocal microscopy of the surgical margins or the association confocal microscopy Raman spectrometry
94

Nanoemulsiones de nistatina para el tratamiento de candidiasis muco-cutáneas

Fernández Campos, Francisco 10 July 2012 (has links)
Se han desarrollado y optimizado dos nanoemulsiones que contienen Nistatina (N1 y N2) para su aplicación en piel y mucosa oral, respectivamente. Estas formulaciones tuvieron un tamaño de gota nanométrico y resultaron ser estables a lo largo del tiempo. Adicionalmente se determinó el comportamiento reológico de ambos sistemas resultando ser fluidos newtonianos. Se evaluó la actividad antifúngica in vitro, observado que la potencia de la nistatina aumentó al ser introducida en las nanoemulsiones, cuando se comparaba con la nistatina libre. El mecanismo de liberación de la nistatina de las nanoemulsiones siguió una cinética de orden uno para ambas formulaciones. Trás el ensayo de permeación ex vivo en piel humana con la nanoemulsion N1 se observó que la cantidad de fármaco permeada fue muy baja, pudiendo descartarse la posible aparición de efectos adversos a nivel sistémico. De la misma manera se realizó el ensayo de permeación ex vivo en mucosa oral porcina para la formulación N2 llegando a la misma conclusión que en el caso de la permeación en piel. En ambos casos la cantidad de fármaco retenido en el tejido (tanto en piel o mucosa) es suficiente para observar un efecto fungistático, fungicida y un prolongado efecto post-antifungico (PAFE). Con el fin de determinar el efecto de la nanoemulsion N2 sobre la mucosa oral se visualizó la ultra-estructura del tejido y no observándose variaciones significativas cuando se comparaban con el control (mucosa no tratada con la nanoemulsion). Las nanoemulsiones N1 y N2 son formulaciones prometedoras para el potencial tratamiento clínico de candidiasis muco-cutáneas. / Muco-cutaneous candidosis is a common opportunistic infection must be treated to prevent other tissue invasion. Nystatin is one of the most prescribed drugs to treat this pathology, but due to its physicochemical properties its pharmaceutical-technological requirements make it a challenge. The purpose of this work was the development and characterization of an optimal nystatin delivery system for the potential treatment of oral candidosis avoiding undesirable side effects and toxicity of potential systemic absorption. Two nanoemulsion (N1 and N2) was developed, evaluated and characterized. It has been formulated successfully as a stable nanoemulsion with a droplet size of 75 and 138 nm, respectively. First order release parameters were estimated using different mathematical approaches and ex vivo permeation of nystatin through human skin and porcine buccal mucosa were found no systemic effects would happen. Microbiologic studies performed revealed an enhanced antifungal effect of the nystatin loaded nanoemulsion. Also the evaluation of buccal mucosa ultrastructure by transmission electron microscopy methodology showing a harmless effect in the mucosa microstructure. We can infer that the selected nystatin nanoemulsion could be potentially used on candidosis infection under mucositis conditions.
95

Epithelial cell regulation of dentritic cell maturation in the airway mucosa : studies in an in vitro model system

Rate, Angela January 2009 (has links)
[Truncated abstract] Atopic asthma pathogenesis is driven by the combined effects of airway inflammation generated during responses to viral infections and aeroallergens, and both of these pathways are regulated by dendritic cells (DC) that differentiate locally from monocytic precursors. These DC normally exhibit a sentinel phenotype characterised by active antigen sampling but attenuated presentation capability, which limits the intensity of local expression of adaptive immunity. How this tight control of airway DC functions is normally maintained and why it breaks down in some atopics leading to immunopathological changes in airway tissues, is unknown. In the airway mucosa, DC are intimately associated with airway epithelial cells (AEC), which are a source of a range of both pro- and anti-inflammatory mediators. A few studies have previously examined the effects of AEC-derived surface-expressed and soluble mediators upon the function of pre-differentiated DC, although there is a dearth of information as to the extent of AEC-conditioning of DC during their generation from incoming monocytic precursors within the airways. Therefore, this study was designed to test the hypothesis that signals from adjacent AEC contribute to regulation of local differentiation of airway mucosal DC, especially in the context of allergic airway disease. A direct co-culture model was developed containing the AEC line 16HBE 14o- as a surrogate for primary AEC, and purified peripheral blood monocytes derived from atopic patients in a GM-CSF/IL-4-enriched cytokine milieu. Cells were cultured for 5 days, at which time the phenotype and functional attributes of the monocyte-derived DC (MDDC) generated in the presence of AEC (AEC-MDDC) were compared to the control MDDC population generated without AEC contact (Ctrl- MDDC). ... In parallel, an attenuation of mRNA boosting for 7 out of 12 selected Th2-asscociated genes as well as IL-13 protein, was observed in AEC-MDDC supplemented cultures compared to ctrl-MDDC supplemented cultures. The data collected in the initial characterisation of the AEC-MDDC in Chapter 3 and further analysis of their gene expression profiles by microarray suggest a number of DC-associated factors could be involved in directing a potential bias against Th2 immunity within the T-cell recall response. These include increased expression of IL- 12 subunit mRNA and the enhanced levels of surface MHC Class II, CD80, ICAM-1 and SLAM. Further to Th1/Th2 modulation, a number of T-regulatory (Treg) genes were differentially expressed in the AEC-MDDC-re-activated CD4+ T-cells, and members of the chemokine and metallothionein families were elevated in the same population. Collectively the results of this study suggest that in the context of the atopic airway microenvironment where there is an abundance of Th2-related mediators, healthy AEC arm locally maturing DC with an arsenal of anti-microbial defences that can be rapidly employed in response to encounter with inhaled pathogens, in particular viruses. In this way, the DC are maintained in an ideal functional phenotype to efficiently mobilise both innate and Th1-polarised adaptive immune defences against infection, whilst achieving tight control of potentially-damaging Th2 immunity to aeroallergens, thus contributing to the maintenance of immunological homeostasis within the respiratory tract.
96

Influência do parasitismo gastrintestinal sobre sinais clínicos, valores de hematócrito (HT) e pproteína plasmática total (PPT), em caprinos e ovinos criados no semi-árido do estado Pernambuco

VALENÇA, Sandra Regina Fonseca de Araújo 15 February 2007 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-11-04T16:06:58Z No. of bitstreams: 1 Sandra Regina Fonseca Araujo Valença.pdf: 256054 bytes, checksum: 8a79a96aeb7492a7703d18cc17301540 (MD5) / Made available in DSpace on 2016-11-04T16:06:58Z (GMT). No. of bitstreams: 1 Sandra Regina Fonseca Araujo Valença.pdf: 256054 bytes, checksum: 8a79a96aeb7492a7703d18cc17301540 (MD5) Previous issue date: 2007-02-15 / It was objectified with this work to search the parasitism frequncy related by farmers and to identify the possible association between the clinical signals, hematological alterations and parasitic infection of goats and sheeps livestock of two cities on Pernambuco State semiarid region, as a part of this State Program of caprine and ovine healthy. A total of 263 goats and 98 sheeps of different breed, young and adults, male and female were used to clinical evaluation and blood and feces sample gasthering whose therefore were send to laboratorial analysis for hematocrit (Ht) measurement, total plasmatic protein dosage (TPP), nematode faecal egg counts (FECs) and fecal culture. The results were evaluated through descriptive association analysis using the EpiInfo 6.02 Statistic Program. Anemia was the most frequent problem, related for 50% of the interviewed farmers, followed by diarrhea with 47,6% of the reports. At about 27% of the ovine samples showed low values of Ht (17% - 23%) whose more than 77% had no clinical disturbs. In the same way, from 25% of caprine samples with low Ht values (8% - 18%) at about68% showed no clinical signs. Just 14,28% of the sheep samples had low TPP values (5 – 5,8 g/dl) whose 85% had no clinical altertions. On caprine population studied, only 5,32% had low TPP values (3,4 – 5,8 g/dl) and of them 85% were considered clinically healthy. Fecal culture was positive for 46,35% of sheep whose at least 57% were considered clinically healthy by clinical evaluation. The OPG was positive for 60% of the goats samples and 73% of them shoned no clinical disturbs. Hematocrit low values (8 – 18%) were observed in 36,58% of sheep and 22% of goats samples in the same way, low values were observed on TPP dosage (3,4 – 5,8 g/dl) in 19,51%. Of ovine and 5,51% of caprine samples, with no dependence of FECs results.The qualitative evaluation (clinical parameters) were not decisive in the identification of parasitized animals and the quantitative analysis (HT, TPP and OPG) were not conclusive for indicate animal illness. It is possible to conclude that rusticity and resistance are important characteristics on the investigated flock. / Objetivou-se com este trabalho pesquisar a freqüência do parasitismo segundo relato de criadores, e identificar a possível associação entre sinais clínicos, alterações hematológicas e infecção parasitária em caprinos e ovinos, criados em dois municípios do Sertão do Estado de Pernambuco, como parte do Programa de Sanidade Caprina e Ovina deste Estado. Foram utilizados 263 caprinos e 98 ovinos, de diferentes raças, jovens e adultos, de ambos os sexos, para avaliação clínica e colheita das amostras de sangue e fezes, destinadas à análise laboratorial para mensuração do hematócrito, dosagem da proteína plasmática total, contagem de ovos de nematóides por gramas de fezes e coprocultura. Os resultados foram avaliados através de análise descritiva de associação, utilizando-se programa estatístico EpiInfo versão 6.02. A anemia foi o problema de maior frequência, sendo relatada por 50% dos criadores, seguida das diarréias com 47,6% dos relatos. Cerca de 27% dos ovinos apresentaram valores de Ht baixos (17% - 23%), dos quais mais de 77% não apresentaram alteração clinica. Da mesma forma, pouco mais de 25% dos caprinos apresentaram valores de Ht baixos (8% – 18%) estando pelo menos 68% destes sem alteração clinica. Apenas 14,28% dos ovinos apresentaram valores de PPT baixos (5 - 5,8 g/dl), destes, cerca de 85% não manifestaram alteração clínica. Entre os caprinos, apenas 5,32% demonstraram valores de PPT baixos (3,4 – 5,8 g/dl), também com pouco mais de 85% dos animais sadios quanto à avaliação clínica. Dos ovinos avaliados, 46,35% foram positivos ao exame coproparasitológico, destes, pelo menos 57% apresentaram-se sadios quanto à avaliação clínica. Entre os caprinos, 60% foram positivos à contagem de OPG, estando pelo menos 73% destes sem alteração clínica. Valores baixos de Ht (8 – 18%) foram observados em apenas36,58% dos ovinos e em 22% dos caprinos, bem como, valores baixos de PPT (3,4 – 5,8 g/dl) foram observados em 19,51% dos ovinos e em 5,51% dos caprinos, independente do resultado da contagem de OPG. As avaliações qualitativas (exame clínico) não foram decisivas na identificação de indivíduos parasitados e as análises quantitativas (Ht, PPT e Contagem de OPG) não significaram animais enfermos. Os achados demonstraram que a rusticidade e a resistência dos animais do rebanho foram características predominantes nesta pesquisa.
97

Avaliação histopatológica, histoquímica e morfométrica dos efeitos da toxicidade aguda do herbicida roundup® nas brânquias e no fígado do peixe Poecilia vivipara / Histopathological evaluation, immunohistochemistry and morphometric analysis of the effects of acute toxicity of the herbicide Roundup ® in gills and liver of the fish Poecilia vivipara

FARIA, Joana Cristina Neves de Menezes 20 May 2009 (has links)
Made available in DSpace on 2014-07-29T15:16:29Z (GMT). No. of bitstreams: 1 joana c n de m faria - dissertacao.pdf: 692068 bytes, checksum: 9ce1455900ab8ef0aa8d6ecf07c0fa97 (MD5) Previous issue date: 2009-05-20 / The indiscriminate use of agricultural pesticides, which contaminate the soil, water, and human beings, has become a problem that causes great concern nowadays. We studied the acute toxic effect of the herbicide Roundup® on animal behavior, tissue, and cells of the neotropical fish species Poecilia vivipara gills and liver in order to determine and compare their histoarchitecture, as well as to identify possible morphological alterations. The average lethal concentrations of Roundup® were calculated and, after that, the specimens were treated with acute exposure of this herbicide (24 h) at the concentrations of 0, 15, 25, and 35 &#956;l per liter of water. The gills and livers were dissected, fixed in neuter formalin and Karnovsky s solution. The analyses, carried out using basic histological, classical histochemical, and morphometric tests, allowed the identification of alterations in the specimens treated compared to the control group. The alterations in animal behavior, tissue, and cells evidenced in this study confirmed the toxic effect of Roundup® on the model-test. Consequently, it is advisable to find a balance between the benefits of this type of product and the protection of the environment and human health. / O uso desordenado e indiscriminado de agrotóxicos, que acabam por contaminar o solo, a água e o homem, é uma problemática atual que suscita grandes preocupações. Os efeitos da toxicidade aguda do herbicida Roundup® sobre o comportamento animal, tecidual e celular das brânquias e do fígado do peixe Poecilia vivipara foram estudados para determinação e comparação de sua histoarquitetura, bem como para identificação de possíveis alterações morfológicas. As concentrações letais médias de Roundup® foram calculadas e, em seguida, os espécimes foram tratados com este herbicida em exposição aguda (24 h) nas concentrações de 0, 15, 25 e 35 &#956;l por litro de água. As brânquias e os fígados foram dissecados, fixados em formalina neutra e em solução de Karnovsky. As análises, feitas por meio de histologia básica, histoquímica clássica e morfometria, permitiram a identificação de alterações nos espécimes tratados quando comparados ao grupo controle. As alterações comportamentais, celulares e teciduais evidenciadas neste estudo confirmaram o efeito tóxico do Roundup® para o modeloteste. Sendo assim, deve-se buscar o equilíbrio entre os benefícios da utilização desses produtos químicos e a proteção do meio ambiente e à saúde humana.
98

Análise proteômica comparativa das secreções das glândulas parotoides e mucosas do sapo Rhinella schneideri e avaliação, in vitro, da atividade antimicrobiana / Comparative proteomic analysis of mucous and parotoid gland secretions of Rhinella schneideri toad and in vitro evaluation of their antimicrobial activity

Fernando Antonio Pino Anjolette 03 September 2015 (has links)
Nas secreções glandulares de anfíbios, muitos dos compostos isolados apresentam ação antifúngica e/ou antibacteriana, cuja função é protegê-los contra infecções, uma vez que estes animais habitam ambientes inóspitos. Os peptídeos têm-se destacado dentre os compostos com atividade antimicrobiana isolados de venenos de diversos animais. Além disso, compostos de natureza não proteica presentes nestas secreções têm demonstrado ação antimicrobiana. O objetivo deste estudo foi, primeiramente, isolar e caracterizar, estruturalmente, compostos com atividade antifúngica relevante. Em um segundo momento, foi realizar um estudo comparativo, através de técnicas ômicas, dos compostos presentes nas secreções das glândulas mucosas e parotoides. Os ensaios antimicrobianos, in vitro, foram realizados com fungos, leveduras e bactérias. O material de baixa massa molecular da água de diálise das secreções das glândulas parotoides apresentou atividade antimicrobiana sobre, principalmente, os fungos filamentosos. Este mesmo material foi submetido a uma filtração em gel, resultando em 11 frações as quais foram testadas contra Microsporum canis no ensaio de diluição seriada. A fração 9 mostrou atividade antifúngica e foi submetida a uma cromatografia de fase reversa, resultando em 9 frações, as quais foram testados contra M. canis. Destas frações, as frações 1 e 9 demonstraram, respectivamente, atividade fungicida e fungistática contra M. canis. No segundo momento, as secreções de ambas as glândulas foram analisadas por nanocromatografia líquida de ultra eficiência acoplada a um espectrômetro de massas de alta resolução. Desta análise, foram obtidos 11.034 compostos, distribuídos entre as secreções de ambas as glândulas. Todos os íons obtidos foram fragmentados (MS/MS) e submetidos à análise no programa PEAKS 6. Foram obtidas 511 sequências de peptídeos e/ou sequências parciais de proteínas das secreções das glândulas mucosas, enquanto que para as secreções das glândulas parotoides foram obtidas 110 sequências. Nas secreções das glândulas mucosas, a maior parte das sequências de aminoácidos são de compostos com massas moleculares entre 1 e 3 kDa, o que corresponde a 82% das sequências obtidas. Já para as secreções das glândulas parotoides, a maioria das sequências de aminoácidos são correspondentes aos peptídeos/proteínas com massas moleculares entre 1 e 2 kDa, o que representa 55% do total de sequências obtidas para esta secreção. As sequências foram analisadas pelo BLAST e revelou que um peptídeo presente nas secreções das glândulas parotoides apresenta 66,7% de identidade com o peptídeo antimicrobiano conhecido como ponericin-G2. Entre as sequências encontradas para as secreções das glândulas mucosas, o destaque foi para o precursor do peptídeo brevinin-1, com identidade de 31,2%. Todas as frações obtidas da filtração em gel das secreções das glândulas mucosas e parotoides foram direcionadas à análise por espectrometria de massas MALDI-TOF, o que resultou em maiores informações sobre a natureza dos compostos presentes nestas frações. A fração 8 das secreções das glândulas mucosas foi fracionada por cromatografia de fase reversa, resultando em 7 frações denominadas Pep1-Pep7. O composto denominado Pep7 teve sua massa molecular (6,012 kDa) determinada através da espectrometria de ressonância ciclotrônica de íons por transformada de Fourier com ionização por electrospray. Os peptídeos Pep4, Pep6 e Pep7 foram sequenciados pelo método de degradação de Edman. Estes peptídeos mostraram identidades com peptídeos antimicrobianos das famílias das tigerinin, shepherin e microcin e brevinins, respectivamente. Este estudo demonstrou que há compostos com atividade antimicrobiana significativa nestas secreções, principalmente para fungos filamentosos. Além disso, foi o primeiro a fazer uma análise comparativa dos compostos presentes nas secreções das glândulas mucosas e parotoides de R. schneideri, destacando a presença de peptídeos antimicrobianos / In amphibian glandular secretions, many of the isolated compounds have antifungal and/or antibacterial action, whose function is to protect the animal against infections, since they usually inhabit inhospitable environments. Peptides have been highlighted among antimicrobial compounds isolated from several venomous animals. In addition, non-proteic compounds present in these secretions have demonstrated antimicrobial action. The aim of this study was to isolate and structurally characterize antifungal compounds from Rhinella schneideri parotoid and mucous secretions. Moreover, in this study it was also performed a comparative study of the composition of mucous and parotid gland secretion by omics techniques. The low molecular weight material from parotoid gland secretion showed antimicrobial activity against filamentous fungi and bacteria. The low molecular weight material that showed antimicrobial activity was subjected to gel filtration, resulting in 11 fractions that were tested against Microsporum canis in serial dilution assay. The fraction 9 showed antifungal activity and it was subjected to a reversed phase chromatography, resulting in 9 fractions, which were tested against M. canis. Among them, fraction 1 and 9 showed fungicidal and fungistatic activity against M. canis, respectively. Gland secretion and the respective low molecular weight material were subjected to gel filtration and, each obtained fraction was analyzed by SDSTricine- PAGE. Secretion of the both glands were also quantitatively analyzed by nano ultraperformance liquid chromatography hyphenated to a high-resolution mass spectrometer. It was obtained 6,460 compounds distributed among secretions of both glands. All obtained ions were fragmented (MS/MS) and analyzed by PEAKS 6 program. 511 sequences were obtained from mucous gland secretion, against 110 sequences from parotoid gland secretion. In mucous gland secretion, most of the amino acid sequences (82%) are compounds with molecular masses between 1 and 3 kDa, while for parotoid gland secretion, most of sequences (55%) correspond to peptides/proteins with molecular masses between 1 and 2 kDa. Sequences were analyzed by BLAST, reveling a peptide in parotoid gland secretion that presents 66.7% of identify with an antimicrobial peptide known as ponericin-G2. Among sequences found in mucous gland secretion, the highlight was to one presenting 31.2% of identify with brevinin-1 precursor. All fractions obtained from gel filtration of the mucous and parotoid gland secretions were analyzed by MALDI-TOF mass spectrometry, which resulted in more informations about the nature of the compounds present in these secretions. Fraction 8 from mucous gland secretion was fractionated by reversed phase chromatography on C18 column, resulting in seven fractions denominated Pep1-Pep7. Pep7 presented a molecular mass of 6.012 kDa when analyzed by Fourier transform ion cyclotron resonance mass spectrometry. In this analysis, six precursor ions were identified, but no sequence was obtained. Pep4, Pep6 and Pep7 were sequenced by Edman degradation method. These peptides showed identity with tigerinin, shepherin and microcin and brevinins, respectively. This study revealed compounds with significant antimicrobial activity in the analyzed secretions, especially to filamentous fungi. In addition, it was the first to perform a comparative analysis of compounds present in mucous and parotoid gland secretion from R. schneideri toad, highlighting the presence of antimicrobial peptides
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Aspectos macroscópicos e microscópicos da vascularização sangüínea na parede do estômago de eqüinos / Macroscopic and microscopic aspects of the blood vascular system in equine stomachs

Luciano da Silva Alonso 09 December 2005 (has links)
Dentre os mecanismos de defesa da mucosa do estômago, o fluxo sangüíneo é citado como responsável por suprir a mucosa com oxigênio e nutrientes, necessários à manutenção da integridade da mesma. O delineamento de experimentos voltados à análise do fluxo sangüíneo na mucosa do estômago de eqüinos requer informações de caráter macroscópico e microscópico referentes à vascularização do órgão. O objetivo deste trabalho foi contribuir com a definição de parâmetros macroscópicos e microscópicos da vascularização sangüínea do estômago de eqüinos. Utilizaram-se 30 estômagos de eqüinos, 15 machos e 15 fêmeas, adultos, sem raça definida e destinados a abate. A divisão do estômago em quadrantes foi utilizada com o objetivo de facilitar a visualização dos diferentes arranjos arteriais encontrados. Avaliou-se o comportamento da artéria gástrica esquerda (AGE), após injeção de látex corado, e também no estado in natura. Foram observados aspectos quantitativos dos ramos das AGE, artéria gástrica direita (AGD), artérias gastroepiploicas esquerda (AGEE) e direita (AGED) e artérias gástricas curtas (AGC). Verificou-se a relação entre número de ramos das AGE e AGC com a área de superfície do estômago, mensurada com software de análise de imagens. Ao exame microscópico foram realizadas mensurações do percentual de vascularização do epitélio aglandular nas regiões das curvaturas maior e menor do estômago. Dentre todas as variáveis analisadas, destacou-se a baixa freqüência de ramificação da AGE para a região da curvatura menor do estômago. O ramo visceral da AGE contribuiu com vasos para a curvatura menor em 26,66% dos casos e o ramo parietal contribuiu com ramos para a mesma região em apenas 20% dos casos. Com base nos resultados obtidos, sugere-se o estudo de particularidades anatômicas da região da curvatura menor do estômago de eqüinos, em pesquisas futuras. / Among the gastric mucous defense mechanisms, the blood flow is cited as responsible for supplying the mucous with oxygen and nutrients, necessary for the maintenance of its integrity. The delineation of experiments related to blood flow analysis in gastric mucous requires macroscopic and microscopic information about stomach vascularization. The aim of this research is to contribute with definitions of macroscopic and microscopic parameters of the equine stomach blood vascularization. Thirty equine stomachs of mixed breed, male or female, all adults and destined to slaughter, were used. The stomach division in quadrants was used for easier visualization of the different artery arrangements found. The left gastric artery (LGA) behavior was evaluated after injection with colored latex and also in natura state. Quantitative aspects of the LGA branches, right gastric artery (RGA), left gastroepiploic artery (LGEA), right gastroepiploic artery (RGEA) and breves gastric arteries (BGA) were evaluated. The relation between the number of LGA and BGA branches and the stomach surface area measured with image analysis software, were taken. Measurements of the vascularization percent of the nonglandular epithelium were taken in major and minor curvatures of the stomach. Among all the analyzed variables, the low occurrence of LGA branch in the minor stomach curvature was emphasized. The LGA visceral branch contributed with vessels for the minor curvature at 26,66% of cases and the parietal branch contributed with branches for this same region at just 20% of cases. Based on theses results, is suggested more studies about anatomical particularities in minor curvature of the equine stomach, in subsequent researches.
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Middle ear structure in relation to function : the rat in middle ear research

Albiin, Nils January 1985 (has links)
The present study was undertaken to evaluate the rat as a model for middle ear re­search. The rat was chosen primarily because the gross structure of its middle ear shows several similarities to that of man. It was considered of great importance to make a thorough structural study of the rat middle ear and to compare the results with those reported for the human middle ear. The thesis therefore includes indepen­dent studies on various aspects of rat middle ear structure and function as well as a review of the literature. The most pertinent findings in the experimental part of this study were the following. The rat Eustachian tube consists of a nasopharyngeal, and a cartilaginous and bony portion. The orifice of the nasopharyngeal portion is composed of two soft tissue lips, which appear to be opened mainly by the action of the salpingopharyngeal mus­cle, but also by the levator and tensor veli palatini muscles. The cartilaginous por­tion appears to be opened solely by the tensor veli palatini muscle. The tensor tympani muscle seems to have no effect on the tube. A ciliated and secretory epithelium lines the inferomedial walls of the tube throughout its length. In the tympanic cavity these thelial cell types extend as two tracts - one anterior and the other inferoposterior to  the promontory - which communicate with the epitympanic/attic compartments. The remaining parts of the tube and the tympanic cavity are covered by a squamous/cuboidal, non-ciliated epithelium. The subepithelial loose connective tissue contains vessels, nerves, and connective tissue cells, among these mast cells. The mast cells are confined to areas covered by the ciliated epithelium, and in the floor of the bulla, in the pars flaccida, and along the manubrial vessels. Glands are restricted to the Eustachian tube. In the clearance/transport of serum-like material, from the epitympanum towards the tube, hydrostatic forces appear to be important. The tympanic membrane is vascularized from meatal and tympanal vessels. Meatal ves­sels branch in the pars flaccida and along the handle of the malleus, where they are localized directly beneath the outer, keratinizing, stratified, squamous epithelium. Furthermore, meatal vessels form a vascular network at the junction between the fi­brocartilaginous annulus and the tympanic sulcus. Tympanal vessels send branches to the periphery of the pars tensa, where they run immediately beneath the tympanal, simple, squamous epithelium. In the major portion of the pars tensa, no blood vessels were found. The rat stapedial artery is a thin-walled vessel with a wide lumen. Without branch­ing, it runs through the tympanic cavity to the extratympanal regions it supplies. In contrast to the corresponding artery in man, the rat stapedial artery persists throughout life. The artery does not seem to be affected by the fluid produced during experimentally induced otitis media with effusion. The middle ear structure in the rat and in man show both similarities and differ­ences. If the differences are kept in mind and considered, it would seem that the rat is indeed a suitable model for experimental middle ear research. / digitalisering@umu

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