Immunohistochemical detection of receptors for oestrogen and progesterone in endometrial glands and stroma during the oestrous cycle in Nelore (Bos taurus indicus) cows

The aim of the present study was to monitor endometrial distribution and concentrations of oestrogen receptors alpha (ER alpha) and progesterone receptors (PR) by immunohistochemistry in Nelore cows (Bos taurus indicus) during the oestrous cycle. Blood samples were collected for progesterone measurement and endometrial samples were taken from the uterine horn contra lateral to the corpus luteum in 16 cows at days 0 (ovulation), 5, 9, 13 and 19 of the oestrous cycle. Immunostaining evaluation for ER alpha and PR in the glandular epithelium and uterine stroma was performed by two methods: positive nuclei counting and staining intensity of the nuclei. Specific positive staining reactions for both receptors were limited to cell nuclei and they were not identified in the cytoplasm. The proportion of ER alpha positive nuclei had a temporal variation throughout the oestrous cycle in both cell types evaluated and was higher in uterine stroma than the glandular epithelium (p < 0.05). The greatest proportion of ER alpha stained nuclei was observed at oestrus and during the initial and mid luteal phase (days 5, 9 and 13) (p < 0.05) in the glandular epithelium and at days 0, 5 and 9 in the uterine stroma (p < 0.01). The proportion of PR positive nuclei remained constant throughout the entire oestrous cycle for both cell types evaluated (p > 0.05). A higher proportion of PR positive nuclei was measured in the uterine stroma compared with the glandular epithelium (p < 0.05). Intensity of staining for ER alpha and PR varied throughout the oestrous cycle (p < 0.01). There was a higher staining intensity at days 0 and 5 in the stroma for ER alpha (p < 0.01) and PR (p < 0.01) and in the glandular epithelium at days 0, 5, 9 and 13 for ER alpha (p < 0.01) and at days 0, 5 and 9 for PR (p < 0.01) when compared with the other evaluated days. These data demonstrate that ER alpha and PR expression varied throughout the oestrous cycle in Nelore cows, in general with highest concentrations at oestrus and the lowest during the luteal phase. This is similar to patterns observed in Bos taurus taurus.

Periacinar Retraction Clefting in Nonneoplastic and Neoplastic Prostatic Glands: Artifact or Molecular Involvement

A space between neoplastic acini and prostatic stroma is not rare and studies have interpreted this as an artifact, considering the absence of endothelial cells indicating vascular invasion. Thus, the aims of this work were to characterize and correlate the occurrence and extent of retraction clefting with the reactivities of alpha and beta dystroglycan (alpha DG, beta DG), laminin, matrix metalloproteinase 2 (MMP-2), p63, insulin-like growth factor 1(IGF-1), vimentin, and fibroblast growth factor 2 (FGF-2). The study was based on nonneoplastic and neoplastic prostatic tissues obtained from necropsies and retropubic radical prostatectomies. The results showed that periacinar retraction clefting was significantly more frequent in prostatic carcinoma samples than in normal prostatic acini. Most of the neoplastic acini (72.0%) showed retraction clefting of more than 50% of circumference, which were significantly more frequent in Gleason score 7 and 6. Decreased collagen and reticular and elastic fibers were verified in the stroma around neoplastic acini. Weak and discontinuous alpha DG, beta DG, and laminin immunoreactivities and intensified MMP-2, vimentin, IGF-1 and FGF-2 immunoreactivities were verified in the neoplastic acini; p63 immunoreactivity was negative in all carcinomas. Thus, these findings showed that the lack of epithelial basal cells, DGs, and laminin and increased MMP-2, IGF-1, and FGF-7 could be considered important pathways in periacinar retraction occurrence. This study demonstrated the origin of and the biological mechanisms responsible for periacinar retraction clefting in prostatic carcinoma.

Leaf glands act as nectaries in Diplopterys pubipetala (Malpighiaceae)

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

OIL GLANDS IN PTERODON PUBESCENS BENTH. (LEGUMINOSAE-PAPILIONOIDEAE): DISTRIBUTION, STRUCTURE, and SECRETION MECHANISMS

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

Cytokine production in lungs and adrenal glands of high and low antibody producing mice infected with Paracoccidioides brasiliensis

Mice genetically selected for high (H) and low (L) antibody production (HIV-A and L-IV-A) were used in an experimental model of paracoccidioidomycosis. In a previous work, it was observed that male HIV-A animals were more susceptible to the infection due to adrenal gland damage. Male HIV-A and LIV-A animals were intravenously inoculated with Paracoccidioides brasiliensis (strain 18) and sacrificed 2, 4, 6, 8 and 10 weeks after inoculation. At each time interval, lungs and adrenals were removed to estimate recoverability of the fungus, as well as to determine Th1 (IFN-gamma, TNF-alpha) and Th2 (IL-4 and IL-10) cytokine profiles. While viable fungi recoverability from the lungs of HIV-A mice was higher after 4 and 8 weeks, there was less fungal recovery from the adrenals of LIV-A animals after the 2nd week, with total fungal elimination after the 8th week. With regard to Th2 cytokines, there was an inhibition in IL-4 production in the organs from infected animals, the extent of which varied according to the organ and the time period after initiation of infection. IL-10 production was found to be lower in both organs. Determination of Th1 cytokines revealed that IFN-gamma production increased in both organs, mainly in the adrenal of LIV-A after 8 and 10 weeks, when these animals showed a total fungal elimination. A significant difference was observed between HIV-A and LIV-A concerning TNF-alpha production in both organs and at all recovery times, in that LIV-A produced a higher level of this cytokine, mainly in the adrenal. These results may explain the high susceptibility of HIV-A to P. brasiliensis infection, is due, at least in part, to adrenal involvement. The higher production of Th1 cytokines by LIV-A in comparison to HIV-A mice may account for LIV-A resistance to P. brasiliensis infection. Our data reveal the importance of this experimental model in the study of the adrenal involvement in paracoccidioidomycosis, since this gland may be highly compromised in the patients, leading to the development of Addison's Disease.

Morphological, histological, and ultrastructural characterization of degenerating salivary glands in females of the cattle-tick Rhipicephalus (Boophilus) microplus (CANESTRINI, 1887) (Acari : Ixodidae)

The present study describes the morphology and ultrastructure of the salivary glands of semi-engorged females of the southern cattle-tick Rhipicephalus (Boophilus) microplus. The acini that compose these glands, at that specific feeding stage, show cells featuring degenerative process of the salivary glands, such as: vacuolated cytoplasm, condensed chromatin, fragmented nuclei, and presence of apoptotic bodies. In addition, the presence of microorganisms was detected, with morphology typical of protozoa, inside these organs. (c) 2005 Elsevier Ltd. All rights reserved.

Structural and cytochemical changes in the salivary glands of the Rhipicephalus (Boophilus) microplus (CANESTRINI, 1887) (Acari : Ixodidae) tick female during feeding

This study describes the morphology of salivary glands of Rhipicephalus (Boophilus) microplus female ticks at beginning of feeding (24-48 h of attachment) and semi-engorged (4-5 days of attachment) to verify the degenerative characteristics of these organs and the secretory phase in which the process begins. At the beginning of feeding, secretion granules had been observed only in the cytoplasm of cells b, c(1), c(2), c(4) (type II acinus) and d (type III acinus), as well as large nuclei with regular and preserved morphology. In the semi-engorged females the acini presented few normal cells, few partially preserved ones, and the remaining ones in several stages of degeneration, that is, with retraction and cytoplasmic vacuolization, and nuclei with chromatin in several stages of condensation, picnotic and/or in fragmentation. In type I acinus and in the excretory ducts of the studied glands, at both feeding stages, no degenerative characteristic was observed. In females of R. (B.) microplus, the salivary glands degenerate asynchronically and precociously when compared with those of others tick's species. (c) 2006 Elsevier B.V. All rights reserved.

Ultrastructural modifications in the venom glands of workers of Apis mellifera L. (Hymenoptera : Apidae) promoted by topical application of juvenile hormone

The present study analyzed, the influence of the treatment with juvenile hormone on the ultrastructure of Apis mellifera L. workers' venom glands. Newly emerged workers received topical application of 1 mu l of juvenile hormone diluted in hexane, in the concentration of 2 mu g/mu l. Two controls were used; one control received no treatment (group C1) and other received topical application of 1 mu l of hexane (group C2). The aspect of the glandular cells, in not treated newly emerged workers, showed that they are not yet secreting actively. Cellular modifications happened according to the worker age and to the glandular area considered. The most active phase of the gland happened from the emergence to the 14th day. At the 25th day the cells had already lost their secretory characteristic, being the distal area the first to suffer degeneration. The treatment with juvenile hormone and hexane altered the temporal sequence of the glandular cycle, forwarding the secretory cycle and degeneration of the venom gland.

Electrophoretical polypeptide pattern of hypopharyngeal glands extracts from workers and males of Scaptotrigona postica Latr. (Hymenoptera, Apidae, Meliponinae)

In S. postica the hypopharyngeal glands are present in workers, males and queens. The glands of newly emerged workers are in a prefunctional phase, in nurse workers they reach their highest development and in forager workers they suffer reabsorption. The newly emerged males and queens, however, have well developed glands that soon start involution. The electrophoretical pattern of worker and male hypopharyngeal glands is compared with the pattern of nurse workers of A. mellifera. The results show simularities, as well as differences among the S. postica males and workers, and among the phases of worker life. The electrophoretic band pattern suggests that the hypopharyngeal glands of nurse workers of S. postica produce substances similar to the ones produced by A. mellifera. The similarity of the extracts of nurse glands of A. mellifera and S. postica, as well as the behavioural similarities of the workers, suggest the same function of this gland in both species.

Cytochemical localization of lipids in the venom glands of worker bees of Apis mellifera (Hymenoptera, Apidae)

The technique of osmium imidazol for the ultrastructural detection of lipids in the secretory cells of the venom gland of 14-days old worker bees of Apis mellifera L. demonstrated the presence of these components at various sites of the gland. These lipids were found mainly associated to the external region of the basal lamina and the microvilli, in the intercellular spaces, in the cuticle of the collecting canaliculi and in the secretion contained in the glandular lumen. Therefore, in addition to revealing the presence of lipids in the secretion, this technique also allowed us to attribute an exogenous origin to the lipids in the secretion; they are taken up from the haemolymph.

Morphological modifications induced by an artificial diet on the hypopharyngeal glands of Apis mellifera (Hymenoptera, apidae) during their degenerative process

The morphological aspects of the hypopharyngeal glands were analyzed in worker bees of Apis mellifera of 15 and 30 days of age. The individuals were kept in a room with controlled temperature at 32degreesC where they received water and either a protein or a high energy food. Nurse and foraging workers were used as a control for the experiment. The morphological results showed that the different diets modified the cell death characteristics and intensified its occurrence. Both diets caused precocious glandular degeneration. However, this anticipation of cell death was more pronounced in the glandular tissue of the workers who received the high energy diet when compared to the glands of the bees fed with the protein meal.The degenerative signs observed were an intense cytoplasmic vacuolization, with a loss of cytoplasm and of the cell boundaries, dilation or condensation of the cells and nuclei, and nuclear fragmentation. At the end of the degenerative process, we observed the extrusion of nuclei and, finally, the dissolution of the glands. The hypopharyngeal glands' remains were found in the haemolymph.

Ultrastructural studies of the mandibular glands of the minima, media and soldier ants of Atta sexdens rubropilosa (Forel 1908)

The mandibular glands of Hymenoptera are structures associated with the mandibles and constitute part of the salivary glands system. Histological studies in workers of Atta sexdens rubropilosa revealed that this gland contains two portions: a secretory and a storage portion or reservoir. Both portions are connected by means of canaliculi. The object of the present work was the study of the ultratructure of the mandibular glands of minima, media and soldier ant of A. s. rubropilosa by TEM techniques. The glands, in the three castes studied, possess a reservoir, constituted by a simple pavementous epithelium surrounded by the cuticular intima and the secretory portion is constituted by cells of rounded shape. The secretory cells, mainly of minima and soldier, were rich in smooth endoplasmic reticulum. The media worker and soldier presented a large number of mitochondria, of varying shape. Well-developed Golgi complexes were also present in the soldiers. The secretory cells in minima, media and soldier were provided with collecting intracellular canaliculi, which were linked to the reservoir through the extracellular portion. The cytoplasm of the canaliculi-forming cell was poor in organelles. In the individuals of the three castes of A. s. rubropilosa, the presence of lipid secretion granules suggested, beyond the other functions, also a possible pheromonal action. The different roles executed by the different insect castes are directly dependent on the glandular products and, consequently, on the secretory cellular characteristics. (c) 2005 Elsevier Ltd. All rights reserved.

Class III glands in the abdomen of Meliponini

Class III tegumentar glands were studied in workers, as well as in queens and males when available, of 56 Meliponini species. The presence and development of these glands varies widely among and within species. However, the queen typically has more glands than do workers, and males rarely have any. Gland development in workers was evaluated by counting and determining the size of cells in histological sections. Laying queens were found to have more active gland cells than did virgins. Cell numbers and cell ultrastructure differed among glands similarly located in workers, queens and males. Cell size and ultrastructure also varied from tergite to tergite. In conclusion, since it is likely that most of them produce pheromones, the wide variability in these glands suggests that they are important to social interaction.

Comparative study of the ultrastructure and secretory dynamic of hypopharyngeal glands in queens, workers and males of Sceptotrigona postica latreille (Hymenoptera, Apinae, Meliponini)

The secretory cycle of hypopharyngeal glands (HPGs) in Scaptotrigona postica resembles that of Apis mellifera: in newly emerged workers the HPGs are in prefunctional state, their maximum development happens in the nurse workers and in forager workers they show signs of reabsorption. In S. postica these glands are also present in queens and males where they are more developed in newly emerged individuals. The ultrastructural features of the HPG secretory cycle in workers of S. postica and A. mellifera are alike: granular endoplasmic reticulum well developed, large secretion masses around the intracellular canaliculus in nurse workers and extensive degenerative structures in forager workers. Then it is suggested that the HPG secrete similar substances in both species. A second secretory cycle seems to occur in early foragers, may be with production of enzymes. The role of the HPGs in queens and males remains unknown but one possibility is enzyme production.