Effects of fipronil (active ingredient of Frontline (R)) on salivary gland cells of Rhipicephalus sanguineus females (Latreille, 1806) (Acari: Ixodidae)

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

Morpho-histochemical characterization of salivary gland cells of males of the tick Rhipicephalus sanguineus (Acari: Ixodidae) at different feeding stages: description of new cell types

This study describes the changes undergone by cells of the salivary glands of unfed and feeding (at day two and four post-attachment) Rhipicephalus sanguineus males, as well as new cell types. In unfed males, types I and II acini are observed with cells undifferentiated, undefined 1 and 2 (the latter, with atypical granules), a, c1 and c3; type III is composed of cells d and e; and type IV present cells g. In males at day two post-attachment, type I acini exhibit the same morphology of unfed individuals. An increase in size is observed in types II, III, and IV, as cells are filled with secretion granules. Some granules are still undergoing maturation. In type II acinus, cells a, b and c1-c8 are observed. Cells c7 and c8 are described for the first time. Cells c7 are termed as such due to the addition of polysaccharides in the composition of the secretion granules (in unfed individuals, they are termed undefined 1). Type III acini exhibit cells d and e completely filled with granules, and in type IV, cells g contain granules in several stages of maturation. In males at day four post-attachment, type I acini do not exhibit changes. Granular acini exhibit cells with fewer secretion granules, which are already mature. In type II acini, cells a, b, c1-c5 are present, type III exhibit cells d and e, and type IV contain cells g with little or no secretion. This study shows that in the salivary glands of R. sanguineus males, cells a, c1, and c3 of type II acinus, and cells d and e of type III do not exhibit changes in granular content, remaining continuously active during the entire feeding period. This indicates that during the intervals among feeding stages, gland cells reacquire the same characteristics found in unfed individuals, suggesting that they undergo reprogramming to be active in the next cycle.

Cephalic salivary gland ultrastructure of worker and queen eusocial bees (Hymenoptera, Apidae)

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

Amblyomma cajennense (Acari : Ixodidae): Salivary gland cells of partially engorged females ticks and the production of lipid by their mitochondria

Morphologically,. The salivary glands of ticks are paired structures consisting of a secretory and an excretory portion, lacking a reservoir for the storage of the secretion. The secretory portion is composed in females by cells that form acini classified into the types I, II, and III. The excretory possess a major duct, from which arise several intermediate ducts that then subdivide to form the canaliculi or acinal tubules, which end at the acini from where they collect the secretion. The present Study describes the ultrastructural changes that occur in the mitochondria of cells of the acini I, II, and III in the salivary glands of partially engorged females of the Cayenne tick Amblyomma cajennense. The results show that this organelle exhibits completely disarrayed crests due to the presence of lipidic material inside the matrix and between the crests, thus demonstrating their participation in the production of the lipids that would be used structurally by the cells. These organelles with ultrastructural changes were denominated derived mitochondria. (c) 2005 Elsevier B.V. All rights reserved.

Cytochemical characterization of Triatoma infestans and Panstrongylus megistus salivary gland cells (Hemiptera, Reduviidae, Triatominae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A new nucleolar body appears in Drosophila saltans salivary gland cells before histolysis, in programmed cell death

The salivary glands of Drosophila saltans ( saltans group, saltans subgroup) analyzed in an advanced stage of programmed cell death showed the appearance of a single, round, nucleolar corpuscle inside the highly altered nucleus of every gland cell, at a time during which the integrity of the original nucleolus was already lost and the original nucleolar material apparently disappeared. In the same nuclei, which already had also lost the characteristic chromosome structure, some delicate chromosome threads were maintained. In many cells, the new nucleolar corpuscle and these chromosome threads are associated. These findings are novel. However, the hypothesis put forward concerning their meaning remains dependent on other studies.

Immunohistochemical study of acinic cell carcinoma of minor salivary gland

Acinic cell carcinoma (ACC) is a rare salivary gland tumour, making up 4% of all minor salivary gland tumours. Typically, it is composed of acinic cells although transitional and duct-like cells are also identified. In the present study, a panel of antibodies was applied to eight minor salivary gland ACCs. Antibodies tested were: cytokeratins 7, 8, 13, 14, 18, 19, vimentin and actin (HHF35). Immunohistochemical staining revealed that cytokeratin 8, among the tested antibodies, was the more specific to neoplastic cells with a pattern of distribution quite variable and peculiar. This staining may be useful in the recognition of neoplastic acinic cells. (C) 1997 Elsevier B.V. Ltd.

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

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)

MORPHOLOGY OF THE SALIVARY-GLAND ACINI IN GRIGIOTERMES-BEQUAERTI (ISOPTERA, TERMITIDAE, APICOTERMITINAE)

The salivary glands of females in Grigiotermes bequaerti (Snyder & Emerson 1949) are composed of many acini. Within the acini, the secretion is collected by canals that join into excretory ducts that open at the acini are formed of 3 classes of cells: secretory, parietal and canalicular. The secretory cells present 2 distinct types which, however, seem to be only different functional stages. Their secretion appears to be highly fluid and accumulates in vacuoles of low electron density. The morphological features of parietal cells point to an ionic transportation function, since they contain an intracellular canaliculus lined with microvilli, and are rich in mitochondria. The final product of the gland may result from the interaction of these 2 cells. The canicular cells located within the acini, in addition to constituting the way of secretion elimination, may have a support function serving as a point of aggregation an interconnection of secretory and parietal cells.

Observations which indicate heterochromatinization of an extra chromosome in the salivary gland cells of Drosophila hybrids

Salivary gland cells of Drosophila mulleri/D. arizonensis aneuploid male hybrids carrying 3 microchromosomes exhibited morphological features which indicate heterochromatinization of one of the small polytene chromosomes. The process apparently changes the chromosome surface producing a coating with a net-like structure and a strong affinity for lacto-acetic orcein. The possibility of a dosage compensatory mechanism operating to counteract the effect of the extra chromosome is discussed on the basis of previous data which indicated that the microchromosomes of these species have ribosomal cistrons and are controlled by regulatory mechanisms especially evident in hybrids. © 1981 Dr W. Junk Publishers.