Morfología de la nefrona de Sparus Auratus / Adelina Zuasti ; Dirección Francisco Hernández Calvo, Agulleiro.

Tesis - Universidad de Murcia.MEDICINA ESPINARDO. DEPOSITO. MU-Tesis 530.Consulte la tesis en: BCA. GENERAL. ARCHIVO UNIVERSITARIO. TM 3416.CRAI CIENCIAS. DEPOSITO. T.D. 101

Ultrastructural and biochemical analysis of epidermal xanthophores and dermal chromatophores of the teleost Sparus aurata

We have studied the pigmentary system of the teleost Sparus aurata skin by electron microscopy and chromatographic analysis. Under electron microscopy, we found the dermis to contain the three major types of recognized chromatophores: melanophores, xanthophores and iridophores. Melanophores were more abundant in the dorsal region, whereas the iridophores were more abundant in the ventral region. The most important discovery was that of epidermal xanthophores. Epidermal xanthophores were the only chromatophores in the epidermis, something only found in S. aurata and in a teleost species living in the Antartic sea. In contrast, the biochemical analysis did not establish any special characteristics: we found pteridine and flavin pigments located mostly in the pigmented dorsal region. Riboflavin and pterin were two of the most abundant coloured pigment types, but other colourless pigments such as xanthopterin and isoxanthopterin were also detected

Morfología de la nefrona de "sparus auratus" / Adelina Zuasti Elizondo.

Resumen de Tesis - Universidad de Murcia.Consulte la tesis en: BCA. GENERAL. DEPOSITO. DPT 86 2389.Consulte la tesis en: BCA. GENERAL. DEPOSITO. DPT 107 1122.MEDICINA ARRIXACA. DEPOSITO. DPT-S E-4 14.NEBRIJA. DEPOSITO. F 16 791

Melanization stimulating factors in the integument of the Mugil cephalus and Dicertranchus labrax

The pigment pattern expression resides in the chromatoblasts of the embryonic skin. The differentiation of these chromatoblasts is influenced by specific local factors such a melanization inhibiting factor (MIF) and a melanization-stimulating factor (MSF). We reveal the presence of these factors by means of a series of experiments on the skin of the marine species of fish Dicertranchus labrax and Mugil cephalus, each with different pigment pattern, the former having a light skin and the latter a darker one. Media conditioned by exposure to dorsal andtor ventral skin, stimulates the melanization of Xenopus laevis neural crest cells throughout a 3 day assay period. Similarly conditioned culture media tested on B16-F10 murine malignant melanocytes, revealed a considerable influence in enzymatic activities: dopachrome tautomerase (DCT), tyrosine hydroxylase and dopa oxidase. The use of media in a dose response basis suggests that the conditioned media may contain both melanophore stimulating and inhibiting factors. The results obtained may actually reflect the resultant activity of the two factors present

Histological changes in connective tissue of rat tails after bipolar radiofrequency treatment

Radiofrequency (RF) has been included in the techniques used in aesthetic surgery/medicine. To date, no studies have performed a histological assessment of changes in the tissue after application of bipolar radiofrequency (BRF) with low energy and frequency. The aim of this study was to examine changes that are produced in connective tissue, principally in the fibroblasts, following BRF treatment. Four groups of rats received a different number of RF sessions (1, 2, 3 and 5). The following parameters were determined: the number of fibroblasts/unit area (FA), the proliferation index (PI), the Heat shock Protein 47 index (HSPI) and the percentage of connective tissue (PC). For statistical analysis, two subgroups (A and B) were made for the variables FA, PI and PC, and another two subgroups (C and D) for the variable HSPI. Significant differences for FA, PI and PC were observed between subgroups A and B, FA and PI having higher values in A, while PC had higher values in B. The HSPI in subgroup C showed significantly higher values than in D. Low energy and frequency BRF led to an increase in the number, proliferation and biosynthetic activity of fibroblasts. The resulting stress suffered by fibroblasts as a result of heat may be associated with the phenomenon of hormesi