18 research outputs found
Cytochemical and immunocytochemical investigations on epidermal mitochondria-rich cells in Salamandra salamandra salamandra (L.) larvae
No full textIn the present study we set out to investigate the expression of E-cadherin, N-cadherin, beta(1)-integrin, fibronectin and vitronectin in the mitochondria-rich cells (MRC) of the skin of Salamandra salamandra salamandra, Moreover MRC were stained with five lectins (Triticum vulgaris; Dolichos biflorus; Glycine max; Arachis hypogaea and Canavalia ensiformis), Larval MRC expressed both adhesion molecules and extracellular matrix glycoproteins and bound all lectins tested, Juvenile MRC did not react with the antisera utilized, but they stained with the lectins. Both the lectins and the regulatory molecules proved to be good cytochemical markers for distinguishing morphologically differentiated MRC during the larval life of Salamandra salamandra salamandra, The adhesion molecules and matrix glycoproteins are of great utility for maintaining the correct tissue architecture, In Salamandra salamandra salamandra larvae these molecules may be crucial for stability and for the correct localization and fate of all skin elements, including specialized cells such as larval MRC
Cultures of skin fragments of Salamandra salamandra salamandra (L.) larvae
No full textAs part of a study on the pigmentary system of Salamandra salamandra salamandra (L.), we cultured skin fragments of 7-10-day-old larvae in order to examine the expression of molecules implicated in cellular adhesion and migration and in regulating cell-cell relationships. Keratinocytes, fibroblasts, Leydig cells, xanthophores, and melanophores migrated from the fragments and were observed in the outgrowth. Keratinocytes and fibroblasts organized into an epidermal layer and an underlying dermal portion. The chromatophores were always located below the epithelial cells, often with fibroblasts. We examined by immunocytochemistry the expression of fibronectin, beta(1)-integrin, L-CAM, and A-CAM in the cultures. Many keratinocytes, fibroblasts, and Leydig cells expressed all the signal molecules tested. Xanthophores and melanophores were only immunoreactive to the anti-adhesion molecules antisera. Since the molecules tested are known to play a role in cell adhesion, growth, and spreading, as well as in regulating tissue differentiation and in maintaining normal tissue morphology, we may hypothesize that in Salamandra salamandra salamandra fibronectin, beta 1-integrin, L-, and A-CAMs concertedly act to stabilize the architecture of the outgrowth and regulate the relationships between chromatophores and those between chromatophores and the other elements of the skin culture
Xanthophore migration from the dermis to the epidermis and dermal remodeling during Salamandra salamandra salamandra (L.) larval development
No full textDuring larval development of Salamandra salamandra salamandra chromatophores organize to form the definitive pigment pattern constituted by a black background with yellow patches that are characterized by epidermal xanthophores and dermal iridophores. Simultaneously the dermis undergoes remodeling from the larval stage to that typical of the adult. In the present study we ultrastucturally and immunocytochemically examined skin fragments of S. s. salamandra larvae and juveniles in order to investigate the modalities of xanthophore migration and differentiation in the context of dermal remodeling from the larval to adult stage. Semithin and thin sections showed that the dermis in newly born larvae consists of a compact connective tissue (basement lamella), to which fibroblasts and xanthophores adhere, and of a loose deep collagen layer. As larval development proceeds, fibroblasts and xanthophores invade the basement lamella, skin glands develop and the adult dermis forms. At metamorphosis, xanthophores reach the epidermis crossing through the basal lamina. We examined immunocytochemically the expression of signal molecules, such as fibronectin, vitronectin, beta(1)-integrin, chondroitin sulfate, E-cadherin, N-cadherin and plasminogen activator, which are known to be involved in regulating morphogenetic events. Their role in dermal remodeling and in pigment pattern formation is discussed
Diffusione dei gamberi d’acqua dolce in Emilia Romagna: problemi ecopatologici legati all’introduzione di specie alloctone. / Presence of freshwater crayfish in Emilia-Romagna region: ecopathological problems joined with exotic species introduction.
No full textLocalization of fibronectin and beta1 integrin in cultured skin fragments of larvae of salamandra salamandra salamandra.
No full textAs part of a study on the pigmentary system of Salamandra salamandra salamandra we cultured skin fragments from 7-10 day old larvae in order to examine the expression of molecules implicated in both cellular adhesion and migration and in regulating the relationships among cells. Skin fragments were cultured for 10-15 days on glass coverslips in Petri dishes. Fragments attached to the coverslips within 24h and fibroblastic and epithelial cells gradually migrated from the fragments. Keratinocytes formed a monolayer above the fibrobasts. Whitin 36-48 h Leydig cells, melanophores and xantophores were observed beneath the keratinocytes. In vitro melanophores and xantophores have two shapes: dendritic when mobile and round when stationary. Immunofluorescence method was applied to the cultures to localize fibronectin and beta1 integrin. Many keratinocytes and fibroblasts showed variably strong immunofluorescence against anti-fibronectin or anti-beta1 integrin. The staining reaction for beta1 integrin was diffuse on the surface of the round melanophores, whereas it did not seem to be expressed on the dendritic chromatophores
Expertise e abilità complesse: uno studio sulla relazione tra correttezza ortografica, fluenze e Executive Attention
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