Ultrastructure of the Lyonet's glands in larvae of Diatraea saccharalis Fabricius (Lepidoptera : Pyralidae)

The Lyonet's gland is found in Lepidoptera larvae, close to the excretory duct of the silk gland. The role played by this gland is still uncertain. This work aims to describe the ultrastructure of the Lyonet's bland in Diatraea saccharalis larvae, offering suggestions regarding its possible function. The insects were reared under laboratory-controlled conditions. The glands were conventionally prepared for transmission (TEM) and scanning (SEM) electron microscopy. SEM showed that Lyonet's glands are paired small structures located in the ventral side of the head. They are composed by clustered long cells resembling leaves. Under TEM observations, each cell is surrounded by a thin basal lamina and contains large stellate nucleus. The cytoplasm presents large and empty canaliculi with small microvilli. The basal plasma membrane forms numerous infoldings where numerous and well-developed mitochondria are concentrated. The cytoplasmic membrane system is poorly developed. Our ultrastructural results suggest that the Lyonet's gland in D. saccharalis larvae may be involved in the uptake of small molecules from the hemolymph no morphological evidences of macromolecules synthesis and secretion were noticed. The detection of nerve fibers in the gland suggest a neural control for the glandular cell function.

Monosomy 22 and del(10)(p12) in an ameloblastoma previously diagnosed as an adenoid cystic carcinoma of the salivary gland

Short-term cultures of a collagenase disaggregated ameloblastoma previously diagnosed as an adenoid cystic carcinoma of the salivary gland were shown by cytogenetic analysis to have the clonal karyotype 45,XY,del(10)(p12), -22. The data may indicate that the loss of genes of chromosome 22, as well as of 10p, could be a critical event in the evolutionary pattern of odontogenic neoplasias. (C) Elsevier B.V., 1996

Presence of wall-devoid micro-organisms in hypopharyngeal glands of forager bees (Hymenoptera, Apidae)

The occurrence of mycoplasma-like bodies in the axial duct and intracellular canaliculli from hypopharyngeal glands of bees (Meliponinae and Apinae) is described. Since they are not found within cells and due to the absence of cellular alterations in the infected glands it is suggested that micro-organisms are not pathogenic to the bees.

Electrophoretical studies of proteins of the hypopharyngeal glands and of the larval food of Melipona quadrifasciata anthidioides Lep (Hymenoptera, Meliponinae)

The electrophoretical protein patterns of hypopharyngeal glands, larval food of Melipona, and royal jelly of Apis were compared.Since protein patterns of hypopharyngeal glands from newly emerged workers, brood cell provisioners and foragers are similar to freshly deposited larval food, the identical protein bands probably represent actual gland secretion. This suggests that, as in Apis, the glands secrete proteins to the larval food, and maintain this ability throughout life, although at slightly different intensities, according to the activity of the bees.The similarity on the electrophoretic profiles of the major larval food protein in Apis and Melipona is an interesting finding because of its probable evolutionary significance.

LOCATION OF RIBOSOMIC CISTRONS IN THE SALIVARY-GLAND CELLS OF D-MULLERI, D-ARIZONENSIS AND THEIR HYBRIDS

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Gingival metastasis from salivary duct carcinoma of the parotid gland

Background: This article reports a rare case of metastasis of salivary duct carcinoma of the parotid gland to the gingiva and reviews the occurrence of metastatic processes to the oral mucosa.Methods: A 67-year-old white male presented with a chief complaint of a painless nodular tissue growth on the gingiva with reportedly 5 months of evolution. The intraoral examination revealed a reddish, superflcially ulcerated nodular lesion (similar to 2 cm in diameter) on the right mandibular buccal attached gingiva, and the clinical aspect was that of a benign reactive lesion. The patient had undergone a parotidectomy for removal of a salivary duct carcinoma of the parotid gland almost 1 year before. A biopsy of the gingival lesion was performed, and the biopsied tissue was forwarded for histopathologic examination.Results: The analysis of the histopathologic sections of the gingival lesion revealed histomorphologic characteristics very similar to those of the primary parotid gland tumor. The definitive diagnosis was gingival metastasis from a salivary duct carcinoma of the parotid gland. The patient died of complications of a pulmonary metastasis I month after the diagnosis of the oral metastatic lesion.Conclusions: Gingival lesions that mimic reactive and hyperplastic lesions may be metastases from malignant neoplasias of diverse origins. An accurate and timely diagnosis is crucial to establish proper and immediate treatment of the metastatic tumor and possibly identify an occult primary malignant neoplasia.

Trajectory of Water- and Fat-Soluble Dyes in the Grass-Cutting ant Atta capiguara (Hymenoptera, Formicidae): Evaluation of Infrabuccal Cavity, Post-Pharyngeal Glands and Gaster

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)