The role of cell surface glycosaminoglycans in cell division: adhesion and proliferation of CHO cells and CHO-K1 cells and a mutant CHO-745 which is deficient in syntesis of proteoglycans due to lack of activity of xylosyl transferase

Na presente tese examinamos o papel dos proteoglicanos e glicosaminoglicanos na divisao celular: adesao e proliferacao de celulas em cultura CHO (chinese hamster ovary) e sua mutante CHO-745 que e deficiente na sintese de glicosaminoglicanos devido a falta da enzima xilosiltransferase. Usando diferentes quantidades de celulas (selvagem e mutante) pouca adesao pode ser observada na presenca de laminina e colageno tipo I. Entretanto quando fibronectina e vitronectina foram usadas como substratos houve um aumento de adesao dos dois tipos celulares. Somente a CHO selvagem mostrou adesao em funcao do tempo sobre colageno tipo IV. Estes resultados sugerem que as duas linhagens celulares possuem diferentes propriedades de adesao. Ensaios de adesao usando colageno tipo IV com celulas CHO cultivadas na presenca de xilosideo ou clorato, mostraram reducao nos niveis de adesao, confirmando a importancia dos glicosaminoglicanos neste fenomeno. Varias evidencias experimentais sugerem que os proteoglicanos de hepara sulfato estao envolvidos na adesao celular como moduladores positivos da proliferaca celular e como composto chave no processo de divisao celular. Ensaios de proliferacao e ciclo celular demonstraram que uma diminuicao das quantidades do proteoglicano nao inibem a proliferacao da mutante CHO-745 quando comparadas com a celula selvagem pois os dois tipos celulares entram na fase S ao redor das 8 horas. A inteiracoes celulas-matriz estao implicadas em uma grande variedade d funcoes. Estas inteiracoes sao principalmente mediadas por integrinas que sa receptores da superficie celular e estao aparentemente envolvidas em adesao, migracao e diferenciacao. Por exemplo, a asj3, integrina esta envolvida na migracao e adesao da celulas sobre fibronectina. Tambem neste estudo, usando marcacao radioativa com sulfato e imunoprecipitacao...(au)BV UNIFESP: Teses e dissertaçõe

Estudo ultraestrutural do estômago de dois teleósteos : Hypostomus commersonii (Reis et al., 1990) e Rhamdia branneri (Hasemann, 1911)

Orientador: Professor Doutor Waldemiro GremskiDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Biológicas, Curso de Pós-Graduação em MorfologiaInclui referências: p. 76-94Área de concentração: Biologia CelularResumo: O presente estudo foi elaborado com o objetivo de se comparar duas espécies de teleósteos de hábitos alimentares diversos: Hypostomus commersonii (REIS et al., 1990), iliófago e Rhamdia branneri (HASEMANN, 1911), onívoro. Foi elucidada a anatomia e histologia do estômago em ambas espécies. Embora a arquitetura das sub-camadas histológicas em ambos os animais utilizados obedeça ao plano estrutural válido para os vertebrados em geral, os resultados mostram que há sensíveis diferenças entre os dois órgãos, refletindo a existência de relação entre o hábito alimentar e a estrutura do órgão. Em H. commersonii o estômago tem a forma de um "U", com paredes delgadas, translúcidas e cheias de ar e desempenha função digestivo-respiratória. R. branneri possui estômago tubular, com parede muscular e espessa, funcionando como órgão de natureza digestiva. Em ambas as espécies o estômago pode ser dividido em três regiões: cárdica, fúndica e pilórica. Não há esfincter na junção com o esôfago, sendo que a ocorrência de um esfincter pilórico é nítida na transição com o intestino. A mucosa em H. commersonii é revestida por epitélio pavimentoso simples, com microvilosidades e sem a presença de qualquer tipo de glândula. E visível a presença de grande número de capilares dipostos na lâmina própria, próximos da luz do órgão. Já em R. branneri as células de revestimento são do tipo cilíndrico simples, com ausência de microvilosidades e presença de glândulas tubulares simples, formadas por células oxinto-pépticas intercaladas por algumas células enteroendócrinas.Summary: The present study was carried out with the objective of comparing the stomach of two species of distinct feeding habits teleosts. A normal anatomy and histology of the stomach of both the species was performed. The teleosts studied were Hypostomus commersonii (REIS et ah, 1990), an herbivorous fish and Rhamdia branneri (HASEMANN, 1911), an omnivorous fish. In spite of the four layers that are characteristic in the alimentary tract of the vertebrates have been seen in both the organs studied, it is shown that exist very clear anatomical and histological differences between them. The H. commersonii stomach presents an "U" form, with very thin and translucid walls and normally it is full of air. This kind of stomach can be considered a respiratory and digestive organ. The lamina exhibits many capillaries wich are disposed near the lumen of the organ. In R branneri was found a stomach with a tubular form and presenting a muscular thick wall. It is disposed in a siphonal way and is restricted to be a food deposit with digestive function. In both the species it can be divided in cardiac, fimdic and pyloric regions. At the point of junction with the esophagus is not possible to see any cardiac sphincter while the transition with the intestine occurs through an evident pyloric sphincter in both the animals used in this study. The H. commersonii mucosa is lined by a simple squamous epithelium with short microvilli and gastric glands are not present. In the R branneri stomach the mucosa is recovered by a simple columnar epithelium, the microvilli are absent and simple tubular gastric glands are present, consisting of oxinto-peptic cells, intercalated by some enteroendocrine cells

Metallic ions in organs of rats injected with metallic particles of stainless steel 316L and Ti6Al4V alloy

Despite the interest in identifying systemic effects caused by the metallic particles released from long term metallic implants in the body, few works support reliable conclusions about the effects of those particles in organs. The aim of the present work is to look for damages in tissues of liver, kidney, lung and heart of rats submitted to injection of Hank's solution contained particles of Ti6Al4V alloy and Stainless Steel 316L, obtained by metal friction. The particles size ranges from 50 to 200 µm for the Ti alloy and from 100 to 500 µm for the 316L. Tissues isolated from the organs after the euthanasia were prepared and analyzed in an optical microscope and Energy Dispersive Spectrometer (EDS). Lesions caused by an inflammatory response such as strange body epithelioid granuloma and giant cells were found in some of the tissues containing yttrium and aluminum

Anatomical Characters of Leave and Stem of Calea serrata Less., Asteraceae

The genus Calea belongs to the tribe Heliantheae and presents about 125 species. Calea serrata, popularly known as erva-de-cobra, chá-amargo and quebra-tudo, is an endemic species found in southern Brazil and is used in traditional medicine to treat ulcers and livers problems. The present work aimed to study the pharmacobotanical characters of leaves and stems of C. serrata for quality control purposes. The plant material was processed according to standard methods of light and scanning electron microscopy. Glandular capitate-stalked and capitate-sessile, uniseriate multicellular non-glandular trichome with tapered apical cell, conical non-glandular trichome, isobilateral mesophyll, secretory ducts near the endoderm and circular shape with six ribs in the stem were important characters, which contributed to the identification of the species

Pharmacobotanical study of Baccharis pentaptera

AbstractBaccharis L. sect. Caulopterae, Asteraceae, comprises thirty species in Brazil that show stems represented by cladodes, which are very similar in morphology. These species are popularly known as “carqueja” in Brazil and Argentina and are used in popular medicine as diuretic and stomachic. The aim of this work was to examine the morpho-anatomical characters of cladodes of Baccharis pentaptera (Less.) DC. for diagnosis purposes. The plant material was prepared by light and scanning electron microscopy. B. pentaptera shows opposite and spread wings in the two-winged cladode axis and irregular arrangement in the three-winged cladode. The wings have a uniseriate epidermis with palisade parenchyma next to both sides of epidermis. The spongy parenchyma crossed by minor collateral vascular bundles is observed in the central region of wings. The glandular trichomes are capitate and biseriate and the non-glandular trichomes are uniseriate and flagelliform with 2–3 cells that extend from the base. In caulinar axis, there are uniseriate epidermis, chlorenchyma alternating with angular collenchyma and perivascular fiber caps adjoining the phloem which is outside the xylem. Prismatic and styloid crystals are verified in the perimedullary zone. These combined characters can assist the diagnosis of Baccharis species sect. Caulopterae

The effect of brown spider venom on endothelial cell morphology and adhesive structures

Spiders of the Loxosceles genus have been responsible for severe clinical cases of envenomation worldwide. Accidents involving brown spiders can cause dermonecrotic injury, hemorrhage, hemolysis, platelet aggregation and renal failure. Histological findings of animals treated by venom have shown subendothelial blebs, vacuoles and endothelial cell membrane degeneration of blood vessel walls, as well as fibrin and thrombus formation. the mechanisms by which the venom causes these disorders are poorly understood. in this work, with an endothelial cell line derived from rabbit aorta, we were able to demonstrate that venom binds to the cell surface and the extracellular matrix. Moreover, we observed that the venom also induced morphological alterations, such as cell retraction, homophilic disadhesion and an increasing in filopodia projections. We also demonstrated that toxins present in the venom disorganized focal adhesion points and actin microfilaments of endothelial cells. Nevertheless, endothelial cell viability showed no alterations compared to controls. Additionally, venom treatment changed the fibronectin matrix profile synthesized by these cells as well as cell adhesion to fibronectin. These results suggest that the deleterious effects of venom on blood vessel walls could be a consequence of the direct effect on the endothelial cell surface and adhesive structures involved in blood vessel stability. These effects indirectly lead to leukocyte and platelet activation, disseminated intravascular coagulation and an increase in vessel permeability. (c) 2006 Elsevier B.V. All rights reserved.Univ Fed Parana, Dept Cell Biol, BR-81531990 Curitiba, Parana, BrazilUNIFESP, Dept Med, Med Clin Discipline, São Paulo, BrazilCatholic Univ Parana, Hlth & Biol Sci Inst, Curitiba, Parana, BrazilUNIFESP, Dept Biochem, São Paulo, BrazilUNIFESP, Dept Med, Med Clin Discipline, São Paulo, BrazilUNIFESP, Dept Biochem, São Paulo, BrazilWeb of Scienc