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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Filogenia, biogeografia e evolução de estruturas secretoras de representantes da subtribo Cajaninae (Leguminosae, Papilionoideae, Phaseoleae)

Araujo, Wanderleia de Vargas January 2019 (has links)
Orientador: Silvia Rodrigues Machado / Resumo: Leguminosae é a terceira maior família dentre as Angiospermas, é cosmopolita, podendo ocorrer em florestas tropicais úmidas, florestas secas, savanas, regiões mediterrâneas e desérticas. Papilionoideae, subfamília com maior riqueza de espécies de Leguminosae, apresenta Phaseoleae como uma de suas tribos de maior importância econômica e alto número de espécies. Cajaninae, por sua vez, é a maior subtribo de Phaseoleae, destacando-se por apresentar aproximadamente 490 espécies distribuídas em 10 gêneros. Os representantes desta subtribo possuem distribuição pantropical, com apenas Rhynchosia e Eriosema ocorrendo nos neotrópicos. De modo geral, as espécies desta subtribo ocorrem em campos graminosos, florestas tropicais secas, regiões semiáridas, áreas degradadas e ambientes propensos à passagem do fogo. A ocorrência das espécies de Cajaninae nestes diferentes ambientes pode estar relacionada à presença de estruturas secretoras, como glândulas vesiculares e tricomas de base bulbosa. Apesar do conhecimento sobre a existência destas estruturas peculiares neste grupo desde o século 19, nenhum estudo detalhado de anatomia, ultraestrutura ou estudos com enfoque evolutivo haviam sido realizados. A subtribo tem sido considerada monofilética, porém os poucos trabalhos filogenéticos existentes abordam Phaseoleae como um todo, possuindo uma amostragem muito baixa dos representantes de Cajaninae, o que não esclarece sua monofilia. Considerando o pouco conhecimento sobre as relações filogené... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Leguminosae is the third largest family among Angiosperms, is cosmopolitan, occurring in humid tropical forests, dry forests, savannas, Mediterranean and desert regions. Papilionoideae, a subfamily with the highest species richness of Leguminosae, presents Phaseoleae as one of its tribes of major economic importance and high number of species. Cajaninae, in turn, is the largest subtribe of Phaseoleae, standing out to present approximately 490 species distributed in 10 genera. The representatives of this subtribe have pantropical distribution, with only Rhynchosia and Eriosema occurring in the neotropics. The species of this subtribe occur in greenfields, dry tropical forests, semi-arid regions, degraded areas and environments prone to fire. The occurrence of Cajaninae species in these different environments may be related to the presence of secretory structures, such as vesicular glands and bulbous based-trichomes. Despite the knowledge about the existence of these peculiar structures in this group since the 19th century, no detailed study of anatomy, ultrastructure or evolutionary approach studies had been performed. The subtribe has been considered monophyletic, but the few existing phylogenetic works address Phaseoleae as a whole, having a very low sampling of Cajaninae representatives, which does not clarify its monophyly. Considering the little knowledge about the phylogenetic relationships in Cajaninae, on the secretory structures that are peculiar to this group and the... (Complete abstract click electronic access below) / Doutor
2

Estudi estructural, ultraestructural i histoquímic de les glàndules sexuals accessòries del mascle reproductor porcí (Sus domesticus)

Badia Brea, Maria Elena 22 October 2003 (has links)
El present treball analitza al microscopi òptic i al microscopi electrònic de transmissió les glàndules sexuals accessòries de Sus domesticus (raça Landrace - varietat anglesa) a partir de mascles reproductors porcins adults i sans. Un millor coneixement dels patrons estructural i ultraestructural normals de las glàndules sexuals accessòries permetrà diagnosticar amb facilitat quina ha estat l'estructura o la funció glandular afectada en mascles en els que s'observa una disminució de la qualitat del semen. Per altra banda, els estudis anatomopatològics s'han de complementar amb tècniques histoquímiques que generalment permeten confirmar o excloure un diagnòstic histopatològic previ.Les glàndules sexuals accessòries del mascle reproductor porcí estan molt desenvolupades i inclouen les glàndules vesiculars, la pròstata i les glàndules bulbouretrals. L'epiteli secretor de les glàndules vesiculars està format per cèl·lules columnars, cèl·lules basals i mastòcits. Les cèl·lules columnars es caracteritzen per presentar tres morfologies diferents que es consideren diferents estadis d'un mateix tipus cel·lular: les cèl·lules principals, les cèl·lules clares i les cèl·lules denses. Les cèl·lules principals secreten activament glicoproteïnes N- i O- glicosilades amb residus d'α-L-fucosa, α(16)fucosa, α-D-mannosa, α-D-glucosa, α- i -D-N-acetilgalactosamina, -D-galactosa-(13)-D-N-acetilgalactosamina, α-D-galactosa, galactosa-(14)-N-acetilglucosamina, D-N-acetilglucosamina i àcid neuramínic. Aquestes glicoproteïnes afavoreixen les interaccions entre l'espermatozoide i l'occit i regulen la permeabilitat de la membrana espermàtica. La pròstata està formada per dues porcions glandulars, el cos de la pròstata (BP) y la pròstata disseminada (DP), entre las quals s'observen diferencies estructurals, ultraestructurals, histoquímiques i funcionals. En ambdues porcions, l'epiteli secretor està constituït per cèl·lules columnars principals, denses i cèl·lules basals, i també per cèl·lules cúbiques en el BP i per cèl·lules mucoses en la DP. En ambdues porcions glandulars, se sintetitzen i secreten N- i O- glicoproteïnes neutres i àcides. Aquestes glicoproteïnes s'alliberen mitjançant un mecanisme regulat en el BP y mitjançant un mecanisme regulat i un constitutiu en la DP. Les glucoproteïnes luminals del BP contenen residus de fucosa, mannosa, α- i -D-N-acetilgalactosamina, galactosa-(14)-N-acetilglucosamina, D-N-acetilglucosamina i àcid neuramínic. En la DP les glicoproteïnes presenten, a més, -D-galactosa-(13)-D-N-acetilgalactosamina i α-D-galactosa. Les glicoproteïnes secretades en el BP i en la DP per via regulada, participen en el control de l'estabilitat del plasmalemma dels espermatozoides, eviten la resposta immune uterina i l'aglutinació dels espermatozoides i afavoreixen la seva motilitat progressiva. Les glicoproteïnes secretades per via constitutiva en la DP protegeixen i lubrifiquen la uretra pelviana.L'epiteli secretor de les glàndules bulbouretrals està format per cèl·lules piramidals principals i denses. Les cèl·lules principals sintetitzen i secreten principalment O-glicoproteïnes àcides carboxilades i sulfatades amb residus glicosídics d'N-acetilgalactosamina, -D-galactosa-(13)-D-N-acetilgalactosamina, α-D-galactosa, D-N-acetilglucosamina i àcid neuramínic. Aquests residus proporcionen resistència a la proteolisi a les O-glicoproteïnes secretades, les quals participen en la lubrificació y protecció de l'epiteli, i intervenen en el control de la permeabilitat del plasmalemma dels espermatozoides i en el transport d'ions al seu través. / The present study evaluates by means of light and transmission electron microscopy, the accessory sex glands coming from adult and healthy boars (Sus domesticus Landrace breed - British variety). A deeper knowledge of the normal structural and ultrastructural patterns of the accessory sex glands will allow diagnosing easily the structure or the glandular function affected when a low spermatic quality is observed. On the other hand, anatomopathological studies must to be complemented with histochemical techniques which generally allow confirming or rejecting a previous histopathological diagnostic. The boar accessory sex glands were very developed and formed by the vesicular glands, the prostate and the bulbourethral glands. Columnar cells, basal cells and mast cells composed the secretory epithelium of the vesicular glands. Columnar cells showed three morphologies, which were considered different stages of the same cell typology and named: principal cells, clear cells and dense cells. Principal cells secreted actively N- and O- glycoproteins that exhibited residues of: α-L-fucose, α(16)fucose, α-D-mannose, α-D-glucose, α- and -D-N-acetilgalactosamine, -D-galactose-(13)-D-N-acetilgalactosamine, α-D-galactose, galactose-(14)-N-acetilglucosamine, D-N-acetilglucosamine and neuraminic acid. These glycoproteins improve sperm-oocyte interactions and regulate plasma membrane permeability.The prostate was constituted by two glandular portions, the prostate body (PB) and the disseminate prostate (DP). Both of them showed structural, ultrastructural, histochemical and functional differences. Principal columnar cells, dense columnar cells and basal cells composed the secretory epithelium of these two glandular parts. The PB contained also cubic cells and the DP contained mucous cells. Both glandular portions synthesised and secreted N- and O- neutral and acid glycoproteins. These glycoproteins were thought to be released by a regulated pathway in the BP while in the DP the glycoproteins seemed to follow a regulated and a constitutive pathway. The BP luminal glycoproteins exhibited residues of: fucose, mannose, α- and -D-N-acetilgalactosamine, galactose-(14)-N-acetilglucosamine, D-N-acetilglucosamine and neuraminic acid. The DP glycoproteins also contained -D-galactose-(13)-D-N-acetilgalactosamine and α-D-galactose residues.The BP and the DP glycoproteins secreted by the regulated pathway participate in the control of sperm membrane stability, avoid uterine immune response and sperm agglutination and, improve their progressive motility. The DP glycoproteins secreted by the constitutive pathway protect and lubricate the pelvic urethra.Principal and dense piramidal cells composed the secretory epithelium of the bulbourethral glands. The principal cells mainly synthesised and secreted carboxylated and sulfated acid O-glycoproteins with residues of: N-acetilgalactosamine, -D-galactose-(13)-D-N-acetilgalactosamine, α-D-galactose, D-N-acetilglucosamine and neuraminic acid. These O-linked oligosaccharides make these proteins extremely resistant to proteolysis, provide lubrication and protection to the epithelium, and participate in ion transport throughout the plasma membrane.

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