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Avaliação das alterações na rede de drenagem de sub-bacias hidrográficas da porção média da bacia do rio Capivari (SP): escala 1:25.000 - subsídio para o planejamento integrado / Assessment of changes in the drainage network of hydrographic sub-basins fo the medium course of the Capivari river basin (SP): scale 1:25.000 - subsidy for integrated planningRibeiro, Rogério Pinto 29 April 2002 (has links)
Este trabalho utilizou a rede de drenagem como geoindicador das modificações ocorridas no período de 23 anos no meio físico em três sub-bacias hidrográficas que compreendem parte do município de Monte Mor(SP) e integram a porção média da bacia hidrográfica do rio Capivari. A metodologia adotada compreendeu a caracterização conjunta dos atributos do terreno, da rede de drenagem e dos processos de ocupação antrópica das sub-bacias. Foram caracterizados os principais atributos do meio físico, tais como geologia, materiais inconsolidados, landforms e declividade. A verificação das alterações neste período foi obtida por meio das análises temporais tanto das variáveis morfométricas da rede de drenagem como da caracterização de ocupação do meio físico. Os dados foram obtidos por atividades de campo, interpretação de fotografias aéreas (escala 1:25.000) de 1972 e de 1995 e processados pelo uso dos programas ENVI e AutocadMap. Os documentos cartográficos gerados foram mapas de documentação, de drenagem, de landforms, de substrato rochoso, de materiais inconsolidados e de uso e ocupação e carta de declividade. O sistema de rede de drenagem configurou-se como um adequado indicador das alterações ambientais ocorridas na área de estudo. A análise morfométrica indicou uma diminuição no número de canais de primeira ordem e no comprimento total dos canais. Estas mudanças condicionaram as modificações dos parâmetros de densidade de drenagem e de densidade hidrográfica. A análise global das mudanças no número de canais de primeira ordem indicou que a maioria deles era de pequenas dimensões (<150m). Tais alterações foram condicionadas pela expansão urbana de Monte Mor e pelo intensivo cultivo de cana-de-açúcar e estão relacionadas às diferentes classes de declividade e aos diversos tipos de relevo, de substrato rochoso e de material inconsolidado / This work used the drainage as a geoindicator to the changes that have taken place during 23 years (1972 to 1995) in the physical environment of three hydrographic sub-basins within the Monte Mor municipal boundaries, located in the medium course of the Capivari river hydrographic basin. The methodological approach comprises a complete characterization of the land attributes, drainage network and anthropic occupation for the sub-basins. The main features of the physical environment, such as geology, unconsolidated materials, landforms and slope were characterized. In order to identify the changes, a temporal analysis of the drainage network morphometric variables and land use were made. Data was collected by field work, aerialphotointerpretation (1:25000 scale) and processed by using the softwares ENVI and AutocadMap. In this work, maps of documentation, drainage, landforms, bed rock, unconsolidated materials and use and occupation and also a slope chart were generated. The drainage systems has showed to be an appropriate indicator of the environmental changes for the studied area. The morphometric analysis indicates a decrease in the number of first-order channels and in the total length of all channels. Modifications in the drainage and hydrographic densities have also been observed. The global analysis of the changes of the number of first order channels has indicated that most of the channels had small dimensions (<150m). Such changes were induced by the urban growth of Monte Mor and by the intensive sugar cane raising. They are also related to the different slope classes and to the several types of landforms, bedrock and unconsolidated materials
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"Técnicas de geoprocessamento aplicadas à análise morfométrica" / GIS techniques applied to morphometric analysisCarlos Henrique Grohmann de Carvalho 05 May 2004 (has links)
Neste trabalho, buscou-se o desenvolvimento e adequação de técnicas de análise morfométrica em Sistemas de Informações Geográficas. Como base de trabalho, foram utilizados os programas livres GRASS-GIS e a linguagem estatística R. Os parâmetros morfométricos estudados foram hipsometria, declividade, orientação de vertentes, perfis em varredura, densidade de lineamentos e de drenagem, rugosidade de relevo, isobases e gradiente hidráulico. A área de estudo localiza-se na borda leste do Quadrilátero Ferrífero (MG), e possui unidades geomorfológicas distintas: um relevo montanhoso a oeste (Serra do Caraça), separado por uma escarpa de centenas de metros de terrenos caracterizados por dissecação fluvial, que abrigam em sua porção central, um planalto sustentado por conglomerados ferruginosos cenozóicos. O elemento principal da análise morfométrica é o Modelo Numérico de Terreno (MDT), que pode ser interpolado a partir de curvas de nível ou de pontos cotados. Há ainda a possibilidade de utilizar MDTs produzidos pela agência espacial americana (NASA), disponíveis gratuitamente via internet. A metodologia proposta envolve principalmente operações básicas de SIG, como conversão entre formatos vetorial e matricial, operações matemáticas simples em mapas raster e interpolação de valores pontuais em superfícies contínuas. Análise de superfícies de tendência foi realizada para verificar a possibilidade de uso do método em estudos de morfotectônica. Foram ajustadas superfícies polinomiais de 1º a 6º grau, e as significâncias estatísticas de cada polinômio e do incremento do grau polinomial foram verificadas com análise de variância. Os mapas morfométricos produzidos permitiram a identificação de estruturas provavelmente relacionadas com a configuração atual da paisagem. Os mapas de resíduos para as superfícies de tendência mais representativas possuem boa correlação com as estruturas inferidas. A metodologia proposta pode ser adaptada aos diversos pacotes SIG existentes no mercado. O uso de programas livres e de código aberto garante o acesso a todos, e sua crescente popularização abre novas perspectivas nesse campo. / This work aims on developing and adaptation of morphometric analysis in Geographic Information Systems. Free softwares GRASS-GIS and R statistical language were used as main applications. Studied morphometric parameters were hypsometry, slope, aspect, swath profiles, drainage and lineament density, surface roughness, isobase and hydraulic gradient. The study area is located in the eastern border of Quadrilátero Ferrífero (MG), and has distinct geomorphological units: a mountainous relief to west (Serra do Caraça), separated by a scarp with hundreds of meters of fall from fluvial dissected terrains, with a flat plateau in its central portion, the Chapada de Canga. The main element for morphometric analysis is the Digital Elevation Model (DEM), which can be interpolated form contours or scattered points. There is also the possibility of utilize NASA' s DEMs, freely available via internet. The proposed methodology deals mainly with basic GIS operations, like conversion between raster and vector, simple mathematic operations on raster maps and interpolation of discrete values into continuous surfaces. Trend-surface analysis was carried out o verify the possibility of use the method for morphotectonic studies. Polynomial surfaces from 1st to 6th degree were adjusted; the statistical significance of each surface and the significance of increasing polynomial degree were verified with analysis of variance. Produced morphometric maps allow identification of structures probably related with present-day landscape configuration. Residuals maps for most representative trend-surfaces keep good correlation with inferred structures. The proposed methodology can be adapted to the variety of GIS packages available in the market. The use of free and open-source softwares guarantees access to everyone, and its increasing popularization opens new perspectives in this field.
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Patologia comparada das malformações congênitas em Bothrops jararaca e Crotalus durissus provenientes do sudeste brasileiro / Comparative pathology of congenital malformations in Bothrops jararaca and Crotalus durissus from Southeast BrazilMarcelo Pires Nogueira de Carvalho 27 June 2014 (has links)
Malformações congênitas, teratogenias ou anomalias do desenvolvimento são processos patológicos definidos como defeitos estruturais que se originam durante a vida embrionária. A ocorrência de teratogenias tem sido relatada em todas as classes de vertebrados e geralmente são incompatíveis com um período de vida prolongado. Uma ampla variedade destas malformações é descrita em répteis, principalmente nas espécies que compreendem a ordem Squamata. Acredita-se que as malformações nestes animais ocorram devido a causas genéticas e/ou ambientais incluindo-se, dentre outras possibilidades, a baixa variabilidade gênica de algumas populações, as alterações de temperatura e umidade ambientais, e a poluição do meio-ambiente. A caracterização e o entendimento dos processos patológicos envolvidos nestas anomalias são de fundamental importância para a compreensão dos fatores que interferem com a conservação dos vertebrados em geral e, no que remete ao presente estudo, das serpentes em específico. Neste contexto, o objetivo desta pesquisa foi caracterizar as alterações macroscópicas e histopatológicas presentes em 102 serpentes acometidas por teratogenias, compreendendo as espécies Bothrops jararaca e Crotalus durissus, correlacionando as alterações histopatológicas identificadas com as malformações. As características macroscópicas das teratogenias foram avaliadas por meio de exames morfométricos, radiográficos, microtomográficos e necroscópicos. Alterações histopatológicas foram identificadas por meio de análise óptica de luz a partir de métodos citoquímicos rotineiros e especiais. O estudo revelou que serpentes da espécie B. jararaca apresentaram lesões axiais mais severas que indivíduos da espécie C. durissus. Nas análises intraespecíficas, fêmeas de C. durissus apresentaram lesões axiais mais severas e em maior número que os machos. No que diz respeito à distribuição destas lesões, indivíduos da espécie C. durissus apresentaram o terço final da coluna, como a região mais acometida pelas malformações axiais. A caracterização microtomográfica de teratogenias específicas (anoftalmia, bicefalia, buftalmia, cauda enrodilhada, ciclopia, cifoescoliose, hidrocefalia, lordose, malformação cefálica e prognatismo), permitiu a análise detalhada destas anomalias e a documentação de alterações morfológicas originais para serpentes como, por exemplo, a agenesia dos ossos frontal, parietal e supraoccipital em B. jararaca portadora de malformação cefálica. A relação entre as alterações histopatológicas e as malformações externas mostrou a existência de correlação estatisticamente significante entre a incidência de doenças renais císticas em serpentes acometidas por braquignatia, quadros inflamatórios oculares em serpentes portadoras de buftalmia, e a desorganização das fibras musculares periaxiais e fusão de corpos vertebrais em serpentes portadoras de lordose. Os dados obtidos constituem uma base de informações úteis para estudos futuros no campo da patologia, teratologia, embriologia e ecotoxicologia em serpentes. / Congenital malformations, developmental abnormalities or teratogeny are pathological processes defined as structural defects that originate during embryonic life. The occurrence of teratogeny has been reported in all classes of vertebrates and is generally incompatible with a prolonged life. A wide variety of these malformations is described in reptiles, especially in species that comprise the Squamata order. It is believed that the defects in these animals occur due to genetic and/or environmental causes including, among other possibilities, the low genetic variability of some populations, changes in environmental temperature and humidity, and environmental pollution. Characterization and understanding of the pathological processes involved in these anomalies are of fundamental importance for the comprehension of factors that interfere with vertebrates conservation in general and, referring to this study, snakes in particular. In this context, the objective of this research was to characterize the macroscopic and histopathological changes present in 102 snakes affected by congenital malformations, comprising the species Bothrops jararaca and Crotalus durissus, correlating histopathological changes with malformations. The macroscopic characteristics of deformities were evaluated by morphometric, radiographic, microtomographic and necropsy analysis. Histopathological changes were identified by light microscopy from routine and special cytochemical methods. The study revealed that B. jararaca snakes had more severe axial lesions than individuals of C. durissus species. In intraspecific analyses, females of C. durissus presented more severe and more numerous axial lesions than males. Regarding lesions distribution, the spinal cord and body final third in individuals of C. durissus species was the region most affected by axial defects. The microtomographic characterization of specific teratogenies (anophthalmia, bicefaly, buphthalmia, curled tail, cyclopia, kyphoscoliosis, hydrocephaly, lordosis, cephalic malformation and prognathism) allowed detailed analysis of these anomalies and the first documentation of certain morphological changes in snakes, for example, agenesis of the frontal, parietal and supraoccipital bones in a B. jararaca presenting cephalic malformation. The relationship between histopathological changes and external malformations showed a statistically significant correlation between the incidence of cystic kidney disease in snakes affected by brachygnatia, ocular inflammatory conditions in snakes affected by buphthalmia, and disorganization of periaxial muscle fibers and fusion of vertebral bodies in snakes presenting lordosis. This research has provided useful and informative data for future studies in the fields of pathology, teratology, embryology and ecotoxicology in snakes.
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Análise morfométrica digital na parede aórtica de suínos após implante de stents não revestidos versus stents revestidos com dacron / Digital morphometric analysis on the aortic wall of pigs after implants of non coated stents versus coated stents with dacronDutra, Clandio de Freitas January 2001 (has links)
Os stents são dispositivos intravasculares implantados com o objetivo de dilatar ou fixar a placa de colesterol contra a parede arterial. O objetivo avaliar dois tipos de stents de aço inoxidável, um recoberto com poliéster (dacron) e outro não recoberto, implantados na aorta infra-renal de suínos jovens, foram avaliados por morfometria digital para medir o espessamento intimal. Foi realizado um estudo experimental randomizado, separados em dois grupos(stents não revestidos e revestidos com dacron) e duas fases (I e II). Oito stents recobertos com dacron e oito stents de aço inoxidável (30mm de extensão e 8 mm de diâmetro), não revestidos, foram implantados através de abordagem retroperitoneal na aorta infrarenal normal de 16 suínos normolipêmicos. Para a passagem do sistema de implante, foi necessário uma pequena arteriotomia na aorta distal (fase I). Após quatro semanas, a aorta com os stents foram removidas em monoblocos (fase II). Os valores de hematimetria e do lipidograma foram coletados nas duas fases e não apresentaram alterações que pudessem influenciar o estudo. Amostras de tecido dos sítios de fixação (proximal e distal) dos stents foram retiradas, confeccionadas lâminas, que foram coradas pelas técnicas de hematoxilina e eosina de Verhoeff e enviadas para análise morfométrica digital. A camada intima distal não apresentou diferença estatística significativa. A camada média proximal das porções proximal e da porção distal não apresentaram diferença entre os grupos. Os dois tipos de stents apresentaram 100% de perviedade, boa biocompatibilidade e boa incorporação a parede aórtica de suínos normolipêmicos. A camada íntima proximal do grupo de stents revestidos com dacron apresentou espessura maior do que os stents não revestidos, mas com significância estatísitica limítrofe. / Stents are intravascular devices implanted with the objective of dilating or fixing the cholesterol plate against the arterial wall. To evaluate, by digital morphometry, the intimal thickening after the placement of two different kinds of stents: polyester covered stainless steel stents (Dacron) and non-covered stents implanted in young pigs’ infrarenal aortas. The stents were made at the Biotransformation Laboratory of Federal University of Rio Grande do Sul. The experiment was performed at the Biotério of University of Caxias do Sul, carried out on two separate groups of pigs. Eight polyester-covered stainless steel stents (Dacron) and eight stainless steel stents (30-mm long, 8-mm diameter) were deployed through extraperitoneal approach in the normal infrarenal aorta of 16 normolipemic pigs. To allow the passage of the delivery system, a small arteriotomy was performed (phase I). After four weeks, the aorta with the stent was removed en bloc. (phase II). The values of the hematimetric and lipid analysis did not show any changes that could influence the study. Tissue samples of the fixing sites (proximal and distal) of the stents were taken. Microscope slices were prepared and submitted to Verhoeff’s hematoxilin and eosin techniques and sent to morphometric analysis.The intima immediately proximal to the device was thicker in the group of covered stents with marginal significance. The distal intimal layer, proximal medial layer of the proximal portion and distal portion did not present statistical difference between the two groups. Patency was 100% in both groups of these normolipemic pigs. After four weeks the intimal layer immediately proximal to the covered stents was ticker when compared to uncovered stents, but this had a borderline significance. The intimal layer distal to covered stents and the media proximal or distal to the devices had similar morphometric features when covered and uncovered stents where compared.
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Ecology and Taxonomy of Ateles geoffroyi in Parque Nacional Pico Bonito, Atlántida, HondurasHines, Justin, justin.hines@opwall.com January 2005 (has links)
The first study on Ateles geoffroyi in Honduras, this research focused on the population of spider monkeys in Parque Nacional Pico Bonito, Atlántida, Honduras. Subgroup size of spider monkeys in Parque Nacional Pico Bonito ranged from 1-23 (n=55) individuals, with a mean subgroup size of 6.93 ± 4.53 individuals, which was larger than nearly all subgroup sizes reported in Central and South America. Mean subgroup composition consisted of 1.65 ± 1.16 adult males, 2.67 ± 1.69 adult females and 1.75 ± 1.92 juveniles. Sex ratio of adult males to adult females was 1:1.62, which was consistent with most Central and South American Ateles studies in the literature.¶
Of a possible 23 identified food tree species from 15 families, and 7 unidentified tree and vine species, spider monkeys were confirmed to consume fruits, leaves and/or seeds from 8 identified tree species, 1 unidentified tree species, and 1 unidentified vine species. Several of the confirmed genera consumed by Ateles in Parque Nacional Pico Bonito were consistent with other studies conducted in Central and South America, including Dialium, Ficus, and Coccoloba.¶
Combining pelage analysis and discriminant analysis of cranial and dental measurements from 140 skins and 253 adult crania, the taxonomy of the Central American Ateles geoffroyi was revised to recognize the taxa Ateles geoffroyi yucatanensis, A. g. vellerosus, A. g. pan, A. g. geoffroyi, A. g. frontatus, A. g. ornatus, and A. g. grisescens, with the recognition of a potential new taxon from northern Honduras, resulting in a revised distribution of Ateles geoffroyi, based on the pelage and cranial analyses.
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Molecular Phylogeography and Species Discrimination of Freshwater <em>Cladophora</em> (Cladophorales, Chlorophyta) in North AmericaRoss, Sara J. January 2006 (has links)
<em>Cladophora</em> is a widespread freshwater filamentous cholorophyte genus and is frequently observed in eutrophic waters where it can produce large nuisance blooms. These blooms can have direct impacts on water intake for power generation, irrigation canals and can be aesthetically unpleasant. Much of the ecological and physiological studies on <em>Cladophora</em> have assumed that the populations of this genus in North America belong to the species <em>Cladophora glomerata</em>. However, this has never been tested despite that it is well documented that identifying freshwater <em>Cladophora</em> to the species level is difficult due morphological variability under different ecological conditions. In addition, the species epithets for freshwater <em>Cladophora</em> are based on European collections and it is not clear if these should be applied to North America. This study examines approximately 40 collections of <em>Cladophora</em> from the Laurentian Great Lakes and 43 from various locations in North America ranging from the Northwest Territories to Puerto Rico. Initially we determined the nucleotide sequences of the internal transcribed spacer (ITS) region of the nuclear ribosomal cistron and observed sequence divergence to be low (0-3%), demonstrating an inability for this marker to resolve species delineation as divergence of this region was low. Amplification of the inter-simple sequence repeat (ISSR) regions were used to analyze microsatellite motif frequency throughout the genome to evaluate the biogeography relationships, including diversity, of freshwater <em>Cladophora</em> sp. five different primers were used on 70 individuals. UPGMA analyses of the presence/absence of bands demonstrate that each of the Great Lake populations separate into groups according to the Lake they were initially sampled from. However, collections from North America are highly variable and do not form well supported biogeographic clades. In addition, these collections appear to be distinct from type cultures of freshwater <em>Cladophora</em> from Europe. Supplementary morphological analysis using suggested taxonomically valid criterion (length and diameter of main axis, ultimate branch, and apical cell) none were able to differentiate Great Lake populations.
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Molecular Phylogeography and Species Discrimination of Freshwater <em>Cladophora</em> (Cladophorales, Chlorophyta) in North AmericaRoss, Sara J. January 2006 (has links)
<em>Cladophora</em> is a widespread freshwater filamentous cholorophyte genus and is frequently observed in eutrophic waters where it can produce large nuisance blooms. These blooms can have direct impacts on water intake for power generation, irrigation canals and can be aesthetically unpleasant. Much of the ecological and physiological studies on <em>Cladophora</em> have assumed that the populations of this genus in North America belong to the species <em>Cladophora glomerata</em>. However, this has never been tested despite that it is well documented that identifying freshwater <em>Cladophora</em> to the species level is difficult due morphological variability under different ecological conditions. In addition, the species epithets for freshwater <em>Cladophora</em> are based on European collections and it is not clear if these should be applied to North America. This study examines approximately 40 collections of <em>Cladophora</em> from the Laurentian Great Lakes and 43 from various locations in North America ranging from the Northwest Territories to Puerto Rico. Initially we determined the nucleotide sequences of the internal transcribed spacer (ITS) region of the nuclear ribosomal cistron and observed sequence divergence to be low (0-3%), demonstrating an inability for this marker to resolve species delineation as divergence of this region was low. Amplification of the inter-simple sequence repeat (ISSR) regions were used to analyze microsatellite motif frequency throughout the genome to evaluate the biogeography relationships, including diversity, of freshwater <em>Cladophora</em> sp. five different primers were used on 70 individuals. UPGMA analyses of the presence/absence of bands demonstrate that each of the Great Lake populations separate into groups according to the Lake they were initially sampled from. However, collections from North America are highly variable and do not form well supported biogeographic clades. In addition, these collections appear to be distinct from type cultures of freshwater <em>Cladophora</em> from Europe. Supplementary morphological analysis using suggested taxonomically valid criterion (length and diameter of main axis, ultimate branch, and apical cell) none were able to differentiate Great Lake populations.
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Kiaulių kiaušidžių folikulų nuo 6 mėnesių iki 1 metų amžiaus palyginamoji morfologija / Comparative morphology of 6 months to 1 years swine ovarian folliclesKraujalytė, Monika 05 March 2014 (has links)
Šiame darbe tirti 6 mėn. – 1 m. amžiaus, Danijos Landrasų veislės kiaulių kiaušidžių įvairių stadijų folikulų morfometriniai ypatumai. Išmatuoti užuomazginių, pirminių ir antrinių kiaušidžių folikulų diametrai, plotai, juose esančių ovocitų diametras, plotas, jų branduolių diametras, plotas; pamatinės membranos storis; folikulinių ląstelių dydis. / The research presented in the Master Thesis was designed to investigate the follicular morphometric peculiarities of ovaries of 6 months – 1 years Danish Landrase pigs. The diameters of primordial, primary and secondary ovary follicles, their areas, diameter and area of oocytes, nuclear diameter and area; the thickness of underlying membrane; the size of follicular cells were investigated.
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Optimized Kava compound treatment reduced porphyromonas gingivalis-induced alveolar bone lossAlshammari, Abdulsalam Khulaif 25 October 2017 (has links)
BACKGROUND: The aim of this study was to assess the effects of a modified Kavain-derived compound, Kava-241, on periodontal destruction in a periodontitis-induced murine model.
METHODS: The study involved 49 mice divided into three groups: control, diseased, and treatment. Diseased mice were infected with P. gingivalis via oral gavage over a 15-day period to mimic periodontal infection. Treated mice received Kava-241 treatment after disease induction over the same period. Bone loss and inflammatory cell activity was assessed by a morphometric analysis of the left mouse maxillae and a histomorphometric analysis of TRAP and H&E stained tissue sections of the right mouse maxillae.
RESULTS: Infected group showed significantly increased alveolar bone loss and inflammatory cells throughout the experimental period in comparison to the untreated control groups. The Infected mice that received Kava-241 showed a significant decrease in inflammatory cell activity in periodontal connective tissues as compared to mice that did not receive any treatment. In periodontal connective tissues, treated mice showed significant decreases of 61.9% and 41.6% of polymorphonucleocyte and monocyte cell counts, respectively, compared to untreated mice. Furthermore, the mice that received treatment post-infection showed a statistically significant decrease in alveolar bone loss. Histomorphometric analysis demonstrated 72.7% and 37.0% reductions of epithelial down-growth and bone loss respectively. Morphometric analysis demonstrated a 46.7% reduction of bone loss in treated mice compared to controls.
CONCLUSION: Our results demonstrate modification of Kava could yield a more effective and safer therapeutic compound in the treatment of periodontal inflammation and bone loss.
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Análise morfométrica digital na parede aórtica de suínos após implante de stents não revestidos versus stents revestidos com dacron / Digital morphometric analysis on the aortic wall of pigs after implants of non coated stents versus coated stents with dacronDutra, Clandio de Freitas January 2001 (has links)
Os stents são dispositivos intravasculares implantados com o objetivo de dilatar ou fixar a placa de colesterol contra a parede arterial. O objetivo avaliar dois tipos de stents de aço inoxidável, um recoberto com poliéster (dacron) e outro não recoberto, implantados na aorta infra-renal de suínos jovens, foram avaliados por morfometria digital para medir o espessamento intimal. Foi realizado um estudo experimental randomizado, separados em dois grupos(stents não revestidos e revestidos com dacron) e duas fases (I e II). Oito stents recobertos com dacron e oito stents de aço inoxidável (30mm de extensão e 8 mm de diâmetro), não revestidos, foram implantados através de abordagem retroperitoneal na aorta infrarenal normal de 16 suínos normolipêmicos. Para a passagem do sistema de implante, foi necessário uma pequena arteriotomia na aorta distal (fase I). Após quatro semanas, a aorta com os stents foram removidas em monoblocos (fase II). Os valores de hematimetria e do lipidograma foram coletados nas duas fases e não apresentaram alterações que pudessem influenciar o estudo. Amostras de tecido dos sítios de fixação (proximal e distal) dos stents foram retiradas, confeccionadas lâminas, que foram coradas pelas técnicas de hematoxilina e eosina de Verhoeff e enviadas para análise morfométrica digital. A camada intima distal não apresentou diferença estatística significativa. A camada média proximal das porções proximal e da porção distal não apresentaram diferença entre os grupos. Os dois tipos de stents apresentaram 100% de perviedade, boa biocompatibilidade e boa incorporação a parede aórtica de suínos normolipêmicos. A camada íntima proximal do grupo de stents revestidos com dacron apresentou espessura maior do que os stents não revestidos, mas com significância estatísitica limítrofe. / Stents are intravascular devices implanted with the objective of dilating or fixing the cholesterol plate against the arterial wall. To evaluate, by digital morphometry, the intimal thickening after the placement of two different kinds of stents: polyester covered stainless steel stents (Dacron) and non-covered stents implanted in young pigs’ infrarenal aortas. The stents were made at the Biotransformation Laboratory of Federal University of Rio Grande do Sul. The experiment was performed at the Biotério of University of Caxias do Sul, carried out on two separate groups of pigs. Eight polyester-covered stainless steel stents (Dacron) and eight stainless steel stents (30-mm long, 8-mm diameter) were deployed through extraperitoneal approach in the normal infrarenal aorta of 16 normolipemic pigs. To allow the passage of the delivery system, a small arteriotomy was performed (phase I). After four weeks, the aorta with the stent was removed en bloc. (phase II). The values of the hematimetric and lipid analysis did not show any changes that could influence the study. Tissue samples of the fixing sites (proximal and distal) of the stents were taken. Microscope slices were prepared and submitted to Verhoeff’s hematoxilin and eosin techniques and sent to morphometric analysis.The intima immediately proximal to the device was thicker in the group of covered stents with marginal significance. The distal intimal layer, proximal medial layer of the proximal portion and distal portion did not present statistical difference between the two groups. Patency was 100% in both groups of these normolipemic pigs. After four weeks the intimal layer immediately proximal to the covered stents was ticker when compared to uncovered stents, but this had a borderline significance. The intimal layer distal to covered stents and the media proximal or distal to the devices had similar morphometric features when covered and uncovered stents where compared.
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