Histology and Histochemistry of the Stomach Epithelium of Pachycondyla (= Neoponera) villosa (Formicidae: Ponerinae)

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

Structure, histochemistry, and ultrastructure of the epithelium and stroma in the gerbil (Meriones unguiculatus) female prostate

The female prostate has aroused scientific interest because it is subjected to the same diseases compromising the male prostate during aging. The objective of this work was to characterize structurally, cytochemically, and ultrastructurally the tissue compartments of the normal adult female prostate of Meriones unguiculatus gerbils. The morphological analyses showed that the gerbil's female prostate is constituted of a cluster of glands and ducts inserted in a musculofibrous stroma. The alveolar epithelium is differentiated and consisted of basal proliferating cells, intermediary cells, and secretory cells. The secretory cells are the most numerous cell type and continuously secrete glycoproteins. The basal cells are the source of the secretory cells and they are then responsible for the alveolus renovation. The prostatic stroma is abundant and rich in elastic and collagen fibers, which are closely associated with smooth muscle cells and fibroblasts. The results showed that the gerbil's female prostate shows morphological and ultrastructural homology to the human female prostate (Skene's gland), and despite being a small organ, it is a mature and physiologically active gland. (C) 2003 Elsevier Ltd. All rights reserved.

Regeneration of the Corneal Epithelium after Debridement of its Central Region: An Autoradiographic Study on Rabbits

Purpose: To investigate the proliferative behavior of the corneal and limbal epithelia after debridement on the central region of the rabbit cornea. Methods: After scraping a circular epithelial area, 5 mm in diameter, in the center of the cornea, (3)H-thymidine ((3)H-TdR) was injected intravitreally, and the rabbits killed from 1 to 49 days afterward. The cornea, together with the adjacent conjunctiva, was processed for autoradiography. Results: The regenerating epithelium at the center of the cornea exhibited high frequencies of labeled nuclei when compared to controls. The mitotic indexes for the limbus were comparable in experimental and control eyes. The unique basal stratum of the limbal epithelium exhibited quick proliferation and vertical migration in all eyes. Cells that remained labeled for four weeks or more were observed throughout the corneal epithelium, including its basal stratum, and this did not depend on epithelial damage. Conclusion: Corneal epithelium wounds are healed by sliding and proliferation of cells surrounding the epithelial gap without any evidence for the participation of the limbal epithelium. Daughter cells labeled with (3)H-TdR were visualized in all layers of the corneal epithelium up to 7 weeks after the DNA precursor injection. However, at this long interval, the only labeled cells in the limbus were in the suprabasal layers.

Proliferation and apoptotic rates and increased frequency of p63-positive cells in the prostate acinar epithelium of alloxan-induced diabetic rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Proliferation of the vascular endothelium of the iris following total debridement of the corneal epithelium and limbal excision of rabbits

Background Damage to the corneal epithelium causes not only a reaction for its repair but also affects other parts of the cornea as well as different components of the anterior segment of the eye. The purpose of this investigation was to analyze the consequences, following epithelial and limbal damage, to the iris of rabbits (Oryctolagus cuniculus).Methods The corneal epithelium was thoroughly scraped followed by surgical excision of the limbus. Next, (3)H-thymidine ((3)H-TdR) was injected intravitreally both into the right (experimental) and left (control) eyes which had their anterior segments processed for autoradiography at intervals of 2, 7 and 21 days after surgery (three rabbits per interval). The irises were also examined with scanning-electron and confocal microscopy after Evans blue injection.Results There was a high frequency of labeling in the cells of the iris blood vessels in the experimental eye, particularly the endothelial ones. The ratio of labeled cells between experimental and control irises was 40:1, with a population of nuclei increasing by 25% and remaining labeled up to 21 days. There was also an increase in the volume of the iris vasculature as shown by confocal microscopy. The high labeling frequencies of the vascular cells were observed throughout the iris from the ciliary to the pupillary regions.Conclusions The lesions on the corneal epithelium elicit proliferation of the iris vascular cells, mainly its endothelium, as well as an early breakdown of the blood-aqueous barrier. The daughter cells resulting from the damage to the eye surface were detected up to 21 days after a single injection of (3)H-TdR, most likely due to their slow turnover. As a consequence of this proliferation, the vasculature of the iris increased in volume.

Morphological and autoradiographic studies on the corneal and limbal epithelium of rabbits

The investigation was centered on the morphological features of the conjunctiva-cornea transition (limbus) of the rabbit eye and the proliferative behavior of its epithelium. The eyes were processed for examination with light and electron microscopy, as well as for autoradiography after intravitreal injection of [H-3]thymidine ([H-3]TdR). At the sites of extraocular muscle insertion, the vascularization of the stroma extended to the peripheral cornea, and the limbal epithelium was thin with its basal stratum made up by clear cuboidal cells. In between the muscle insertions, the cuboidal clear cells, as well as the stroma blood vessels; were scarce. At the light microscope level, the basement membrane was distinct in the cornea but not in the limbus or the conjunctiva. Autoradiographs demonstrated that, at the limbus, the basal cells migrated very quickly to the suprabasal region and remained there up to the 28-day interval. Labeled cells were identified in all epithelial layers of the cornea, including the basal one, at 21 and 28 days but not in the limbal basal clear cells. The rate of renewal of conjunctival epithelium was similar to that observed for the transition with scarce clear cells. The high-resolution autoradiographs demonstrated that the basal cuboidal clear limbal cells exhibit a quick renewal and that they are not label-retaining cells. These latter ones were detected all over the corneal epithelium and in the suprabasal layers of the limbus up to 28 days, in physiological conditions, without the need of stimulation by damage to the corneal epithelium.

Characterization of melanin pigment produced by Aspergillus nidulans

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Pigmentação testicular em Physalaemus nattereri (Steindachner) (Amphibia, Anura) com observações anatômicas sobre o sistema pigmentar extracutâneo

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

Effects of nitrate and phosphate availabilities on growth, photosynthesis and pigment and protein contents in colour strains of Hypnea musciformis (Wulfen in Jacqu.) J.V. Lamour. (Gigartinales, Rhodophyta)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ultrastructure of ovarian follicular epithelium of the Amazonian fish Pseudotylosurus microps (Teleostei: Belonidae): morphological and histochemical characterization of the intercellular deposits

Neste trabalho é mostrada a grande quantidade de material eletrondenso intercelular no epitélio folicular de P. microps. Aparentemente, o material é captado da circulação e enviado para o folículo por meio dos espaços intercelulares, acumulando-se nos espaços intercelulares médio-apicais do epitélio e no espaço perioocítico. A acumulação é iniciada no oócito primário e prossegue até a vitelogênese. A natureza química desse material é discutida.

Morphological findings in the tracheal epithelium of dogs exposed to the inhalation of poorly conditioned gases under use of an endotracheal tube or laryngeal mask airway

OBJETIVO: Avaliar as alterações morfológicas no epitélio traqueal de cães expostos à inalação de gases pouco condicionados, sob ventilação com tubo traqueal (TT) ou máscara laríngea (ML). MÉTODOS: Doze cães adultos foram divididos aleatoriamente em dois grupos: grupo TT (n-6) e grupo ML (n-6), submetidos à anestesia venosa e ventilação mecânica, em sistema sem reabsorção de CO2. Foram registrados parâmetros hemodinâmicos e ventilatórios, temperatura timpânica, temperatura, umidade relativa e absoluta do ar ambiente e dos gases inalados durante 3 horas. Ao término do experimento, os animais foram submetidos a eutanásia e realizadas biópsias ao longo do segmento traqueal para estudo morfológico. Três cães saudáveis foram utilizados para controle morfológico. RESULTADOS: A temperatura dos gases inalados manteve-se entre 24ºC e 26ºC, a umidade relativa entre 10% e 12%, e umidade absoluta entre 2 -3 mg H2O.L-1 sem diferença significativa entre os grupos. em ambos os grupos a análise histológica evidenciou processo inflamatório epitelial e congestão no córion, e a microscopia eletrônica de varredura mostrou agrupamento e desorganização ciliar. A microscopia eletrônica de transmissão detectou maiores alterações no grupo TT do que no ML, como alargamento das junções intercelulares, desorientação ciliar, vacuolização citoplasmática, alterações nucleares como pcinose e condensação da cromatina. CONCLUSÃO: A máscara laríngea determinou alterações menos pronunciadas no epitélio traqueal de cães expostos à inalação de gases pouco condicionados.

The use of scaning electron microscopy in postvaccinal evaluation of tracheal epithelium of Coturnix coturnix japonica

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

CHOLECYSTOKININ-LIKE IMMUNOREACTIVE RETINAL GANGLION-CELLS PROJECT TO THE VENTRAL LATERAL GENICULATE-NUCLEUS IN PIGEONS

A subpopulation of retinal ganglion cells projecting to the pigeon ventral lateral geniculate nucleus was shown to contain cholecystokinin-like immunoreactivity. These ganglion cells were mainly distributed in the peripheral retina, and their somata sizes were medium to large (14-23-mu-m). Taken together with previous findings, these results indicate that the retinal input to the ventral geniculate is chemically heterogeneous.