Early embryonic death in mares: clinical and hormonal aspects

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

Cytotoxicity of Portland Cement with Different Radiopacifying Agents: A Cell Death Study

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Immunohistochemical detection of estrogen receptor beta in alveolar bone cells of estradiol-treated female rats: possible direct action of estrogen on osteoclast life span

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Cell death evaluation in benzo[a]pyrene-transformed human breast epithelial cells after microcell-mediated transfer of chromosomes 11 and 17

The incidence of apoptosis and nuclear instability, including the incidence of catastrophic death, were investigated in benzo[a]pyrene (BP)-transformed human breast epithelial cells (BP1-E cell line) after microcell-mediated transfer of chromosomes 11 and 17. Since the introduction of normal chromosomes 11 and 17 into tumorigenic human breast BP1-E cells reverts some of these cells' characteristics (especially those affected by microsatellite instabilities and loss of heterozygosity) those of parental non-transformed MCF-10F cells, it was expected that the cell death rates would also be affected by this treatment. The transfer of the mentioned chromosomes, especially chromosome 17, to tumorigenic BP1-E cells increased the apoptotic ratios and decreased the nuclear instability ratios, thus showing that the microsatellite instability and loss of heterozygosity induced by BP in these chromosomes of MCF-10F cells affect the control of cell death mechanisms. (C) 2003 Elsevier B.V. All rights reserved.

The 5S rDNA family evolves through concerted and birth-and-death evolution in fish genomes: an example from freshwater stingrays

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

Maternal undernutrition and the offspring kidney: from fetal to adult life

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

Differentiation of the worker's ovary in Apis mellifera L. (Hymenoptera, Apidae) during life of the larvae

The aim of the present study is to characterize the way worker and queen ovaries differentiate in, Apis mellifera, a species with trophic determination of female castes. A morphological study carried out with light and transmission electron microscopy showed that the differences in ovary development between the two castes begin as soon as the differential nursing of larvae is initiated. The decrease in ovariole number in worker ovaries is due to a process of cell death occurring in germinative cells and autophagic regression of somatic cells in the ovarioles that commence in the third instar larvae and proceed until the fifth instar where the process is more intense. Germinative cell death leads to ovariole disintegration and incorporation of the remaining somatic cells of the latter into the stromatic cells in such a way that the total volume of the ovary is little affected during larval development, although the ovariole number decreases. By the end of the larval stage, loss of cells is observed among the stromatic cells of the ovary. As a result, the ovary starts to decrease in volume and takes on the adult form.

In situ localization of heat-shock proteins and cell death labelling in the salivary gland of acaricide-treated honeybee larvae

The effects of the acaricides, rotenone and oxalic acid (OA) on salivary glands of honeybee larvae were evaluated. Immunohistochemical methods were used to detect cell death and heat-shock protein (HSP70 and 90) localizations. Heat-shock proteins (HSP70 and 90) were localized in the cytoplasm and/or the nuclei of secretory gland cells, both under stress and in normal conditions. In rotenone-treated larvae, there were no changes in the normal level of cell death and also there were no morphological alterations in the secretory cells. In the larvae treated with oxalic acid, the salivary gland showed varying degrees of morphological cellular alteration and an increase in the cell death level. The present data suggest that stress-induced HSP70 might have an antiapoptotic effect while the stress-induced HSP90 might have a chaperone function in the larval salivary glands.

Modes of cell death in the hypopharyngeal gland of the honey bee (Apis mellifera L)

Different modes of cell death have been revealed in the regressing hypopharyngeal glands of worker honey bees. The hypopharyngeal gland, which is well developed in young nursing bees to produce protein for larval food, was seen to regress naturally in foraging adult worker bees. A range of techniques including histology, cytochemistry, in situ TUNEL, Annexin V and Comet assays indicated that cells within the gland demonstrate progressive symptoms of apoptosis, necrosis and a vacuolar form of programmed cell death. The latter mode of cell death did not display chromatin margination, but was accompanied by an enhanced level of autophagic and hydrolytic activity in which a cytosolic source of acid phosphatase became manifest in the extra-cisternal spaces. Normal and annexin-positive cells were found to occur in the younger nursing bees, whilst necrosis and an aberrant vacuolar type of apoptosis predominated in the older foraging bees. The relevance of these results to the classification of programmed cell death is discussed. (C) 2000 Academic Press.

Morphological characterization of cell death during the ovary differentiation in worker honey bee

Cell death that occurs during ovary differentiation in the honeybee worker's larval development accounts for ovariole reabsorption. From a morphological standpoint, three modes of death were detected. Germinative cells in the ovarioles die by an apoptotic-like process, whereas the somatic cells die by an autophagic process, type 11 cell death; and during pupation, stromatic and ovarian capsular cells die through cytoplasmic disintegration, releasing their components into the hemolymph. These modes of cell death are in part determined by the pattern of tissue organization within which the cell occurs. (C) 2002 Elsevier B.V. Ltd. All rights reserved.

Programmed cell death in the larval salivary glands of Apis mellifera (Hymenoptera, Apidae)

The morphological and histochemical features of degeneration in honeybee (Apis mellifera) salivary glands were investigated in 5th instar larvae and in the pre-pupal period. The distribution and activity patterns of acid phosphatase enzyme were also analysed. As a routine, the larval salivary glands were fixed and processed for light microscopy and transmission electron microscopy. Tissue sections were subsequently stained with haematoxylin-eosin, bromophenol blue, silver, or a variant of the critical electrolyte concentration (CEC) method. Ultrathin sections were contrasted with uranyl acetate and lead citrate. Glands were processed for the histochemical and cytochemical localization of acid phosphatase, as well as biochemical assay to detect its activity pattern. Acid phosphatase activity was histochemically detected in all the salivary glands analysed. The cytochemical results showed acid phosphatase in vesicles, Golgi apparatus and lysosomes during the secretory phase and, additionally, in autophagic structures and luminal secretion during the degenerative phase. These findings were in agreement with the biochemical assay. At the end of the 5th instar, the glandular cells had a vacuolated cytoplasm and pyknotic nuclei, and epithelial cells were shed into the glandular lumen. The transition phase from the 5th instar to the pre-pupal period was characterized by intense vacuolation of the basal cytoplasm and release of parts of the cytoplasm into the lumen by apical blebbing; these blebs contained cytoplasmic RNA, rough endoplasmic reticule and, occasionally, nuclear material. In the pre-pupal phase, the glandular epithelium showed progressive degeneration so that at the end of this phase only nuclei and remnants of the cytoplasm were observed. The nuclei were pyknotic, with peripheral chromatin and blebs. The gland remained in the haemolymph and was recycled during metamorphosis. The programmed cell death in this gland represented a morphological form intermediate between apoptosis and autophagy.

Proteomic analysis reveals suppression of bark chitinases and proteinase inhibitors in citrus plants affected by the citrus sudden death disease

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

Fipronil-induced cell death in salivary glands of Rhipicephalus sanguineus (Latreille, 1806) (Acari: Ixodidae) semi-engorged females

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

Markers of cell death in salivary glands of males of the tick Rhipicephalus sanguineus (Latreille, 1806) (Acari, Ixodidae)

The salivary glands of Rhipicephalus sanguineus males at stages: unfed (control), at day seven post-attachment, and at days three and seven post-detachment from the host were examined using methods of enzymatic analysis and cell viability. At these stages of feeding, different staining patterns were observed in the cells of type IV, III, II and I acini, which were affected by degeneration in this sequence. Acid phosphatase reaction was inversely proportional to that of ATPase, while ATPase reaction was proportional to membrane integrity.Salivary gland cells of unfed males exhibited intact nucleus and plasma membrane, suggesting that the acid phosphatase detected may participate in the normal physiology of acini. In males at day seven post-attachment, intact membranes were observed in almost all types of acini, as well as stronger reaction for acid phosphatase, nuclear changes, and decrease in ATPase reaction, changes associated with the degenerative process. At days three and seven post-detachment degeneration progress, being observed loss of membrane integrity, nuclear changes, prominent decrease in ATPase reaction, and an increase in acid phosphatase reaction in the first case and a decreased of it at day seven post-detachment from the host. During cell death, alterations occurred in the following sequence: a) nuclear changes, b) loss of ATPase reaction, c) loss of integrity of the plasma membrane, and d) increase of acid phosphatase. The latter might be associated with the late degradation of cytoplasmic remnants, characterizing the process of cell death in glands of R. sanguineus males as atypical or non-classic apoptosis. (C) 2008 Elsevier B.V. All rights reserved.

Nuclear alterations associated to programmed cell death in larval salivary glands of Apis mellifera (Hymenoptera : Apidae)

The silk glands of bees are a good model for the study of cell death in insects. With the objective to detect the nuclear features during glandular regression stage, larvae at the last instar and pre-pupae were collected and their silk glands were dissected and processed for ultrastructural analysis and histologically for cytochemical and imunocytochemical analysis. The results showed that the cellular nuclei exhibited characteristics of death by atypical apoptosis as well as autophagic cell death. Among the apoptosis characteristic were: nuclear strangulation with bleb formation in some nuclei, DNA fragmentation in most of the nuclei and nucleolar fragmentation. Centripetal chromatin compaction was observed in many nuclei, forming a perichromatin halo differing from typical apoptotic nuclei. With regards to the characteristics of autophagic-programmed cell death, most relevant was the delay in the collapse of many nuclei. (C) 2006 Elsevier Ltd. All rights reserved.