Morphology and ultrastructure of the temporomandibular joint disc in human fetuses 21 to 28 weeks old

Ultrastructure of human fetuses temporomandibular joint is poorly understood specially by scanning electron microscopy and cryofracture techniques. In this work, the morphology of the temporomandibular joint (TMJ) articular disc and its insertions was examined in 12 human fetuses. Four TMJs were sectioned in the frontal and sagittal planes and five were cryofractured prior to examination using light and scanning electron microscopy. The three remaining TMJs were fixed, embedded in paraffin, sectioned and stained with HE and NMC trichrome. The articular disc inserted into the mandibular head, temporal bone, joint capsule and upper head of the lateral pterygoid muscle. The fibrous architecture of this disc was complex, with longitudinal fibers predominating in the upper and lower regions, and interposed transverse and oblique fibers predominating in the central region.

Evaluation of egg morphology from ethanol preserved females of Anastrepha sp.2 aff. fraterculus (Diptera: Tephritidae) / Avaliação da morfologia dos ovos de fêmeas de Anastrepha sp.2 aff. fraterculus (Diptera: Tephritidae) preservadas em etanol

A morfologia dos ovos de Anastrepha sp.2 aff. fraterculus foi avaliada em amostras de ovaríolos maduros obtidos de fêmeas preservadas em etanol, de fêmeas recém-mortas e comparadacom a de ovos recém-depositados. As características da ornamentação do córion, assim como da estrutura interna dos ovos recém-depositados também puderam ser observadas nos ovos dissecados das fêmeas. Fêmeas preservadas em etanol podem ser utilizadas para análise da morfologia dos ovos, possibilitando a inclusão de espécies, cujos ovos não são obtidos facilmente, nesse tipo de análise.

Features of eggshell morphology in Anastrepha sp.2 aff. fraterculus were evaluated in mature ovariole ova dissected from females preserved in ethanol, and from ovaries of fresh killedfemales in comparison to that of freshly laid eggs. The characteristics of sculpturing as well as of internal structure of the chorion in oviposited eggs could be observed in both samples of mature ovariole ova. Ethanol preserved females may be used as a source of eggs for morphological studies allowing this kind of analysis to species whose eggs are not readily obtained.