Spontaneous germ cell death by apoptosis in epididymis of the adult bat Artibeus lituratus

Many factors can lead cells to apoptosis during the various stages of cell life. This study was undertaken to characterize germ cell death in the epididymis of the adult Artibeus lituratus by histochemical and immunohistochemical techniques using light microscopy and transmission electron microscopy. The results showed that cells with a nuclear phenotype and ultrastructural characteristics of chromatin compaction were common in apoptosis. The Apoptag test confirmed that the suspected cells were apoptotic. It is suggested that immature germ cells, when released from the germinative epithelium, may be directed towards the epididymis instead of being disposed of in the testicle. Furthermore, intact immature cells can leave the testicle in the initial phases of apoptosis and complete this phenomenon in the epididymis.

Meiotic nucleolar cycle and chromatoid body formation during the rat (Rattus novergicus) and mouse (Mus musculus) spermiogenesis

The aims of the present study were to follow the nucleolar cycle in spermiogenesis of the laboratory rodents Rattus novergicus and Mus musculus, to verify the relationship between the nucleolar component and chromatoid body (CB) formation and to investigate the function of this cytoplasmic supramolecular structure in spermatogenic haploid cells. Histological sections of adult seminiferous tubules were analyzed cytochemically by light microscopy and ultrastructural procedures by transmission electron microscopy. The results reveal that in early spermatids, the CB was visualized in association with the Golgi cisterns indicating that this structure may participate in the acrosome formation process. In late spermatids, the CB was observed near the axonema, a fact suggesting that this structure may support the formation of the spermatozoon tail. In conclusion, our data showed that there is disintegration of spermatid nucleoli at the beginning of spermatogenesis and a fraction of this nucleolar material migrates to the cytoplasm, where a specific structure is formed, known as the "chromatoid body", which, apparently, participates in some parts of the rodent spermiogenesis process. (c) 2007 Elsevier Ltd. All rights reserved.

Neonatal Gonocyte Differentiation in Mongolian Gerbil Meriones unguiculatus Involves Asynchronous Maturation of Seminiferous Cords and Rapid Formation of Transitional Cell Stage

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Diabetes induces stromal remodelling and increase in chondroitin sulphate proteoglycans of the rat ventral prostate

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

Morphological Changes of the Epididymis and Description of the Excurrent Ducts of Phrynops geoffroanus (Testudines: Chelidae) During the Reproductive Cycle

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

Characterization of Mongolian Gerbil Chromatoid Bodies and Their Correlation with Nucleolar Cycle During Spermatogenesis

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

Oxidative stress markers and apoptosis in the prostate of diabetic rats and the influence of vitamin C treatment

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Osmotic dehydration of apples in sugar/salt solutions: Concentration profiles and effective diffusion coefficients

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

Aggregation behavior of aqueous dioctadecyldimethylammonium bromide/monoolein mixtures: A multitechnique investigation on the composition and temperature

A recently described non-viral gene delivery system [dioctadecyldimethylammonium bromide (DODAB)/monoolein (MO)] has been studied in detail to improve knowledge on the interactions between lamellar (DODAB) and non-lamellar-forming (MO) lipids, as a means to enhance their final cell transfection efficiency. Indeed, the morphology, fluidity, and size of these cationic surfactant/neutral lipid mixtures play an important role in the ability of these systems to complex nucleic acids. The different techniques used in this work, namely dynamic light scattering (DLS), fluorescence spectroscopy, differential scanning calorimetry (DSC), cryogenic transmission electron microscopy (cryo-TEM), light microscopy (LM), and surface pressure-area isotherms, allowed fully characterization of the phase behavior and aggregate morphology of DODAB/MO mixtures at different molar ratios. Overall, the results indicate that the final morphology of DODAB/MO aggregates depends on the balance between the tendency of DODAB to form zero-curvature bilayer structures and the propensity of MO to form non-bilayer structures with negative curvature. These results also show that in the MO-rich region, an increase in temperature has a similar effect on aggregate morphology as an increase in MO concentration. (C) 2012 Elsevier B.V. All rights reserved.

Preparation of the Ca-diclofenac complex in solid state

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo comparativo das alterações celulares no líquen plano e no carcinoma epidermóide bucal

Atualmente, muito se discute a respeito da natureza pré-maligna do líquen plano bucal. OBJETIVO: O presente trabalho tem como objetivo analisar as alterações das células epiteliais presentes no líquen plano bucal, comparando-as com aquelas observadas no carcinoma epidermóide. MATERIAL E MÉTODO: Cortes histológicos de líquen plano bucal e carcinoma epidermóide, corados com hematoxilina-eosina, foram analisados por meio da microscopia de luz. RESULTADO: As alterações mais frequentemente observadas no líquen plano bucal foram aumento da relação núcleo/citoplasma (93,33%), espessamento da membrana nuclear (86,67%) e bi-ou multinucleação (86,67%). O teste t de Student (alfa=5%) revelou haver diferença estatisticamente significante entre o número médio de alterações celulares no líquen plano bucal (5,87±1,57) e no carcinoma epidermóide (7,60±1,81). Quanto aos tipos de alterações, o teste de qui-quadrado também revelou haver diferença estatisticamente significante entre as lesões avaliadas em relação às seguintes alterações celulares: hipercromatismo nuclear, mitoses atípicas, pleomorfismo celular e diferenciação celular anormal (p<0,05). CONCLUSÃO: Apesar de que, em alguns casos, alguns patologistas possam fazer confusão no diagnóstico histopatológico do líquen plano bucal, os resultados obtidos neste estudo mostram que as alterações presentes no líquen plano bucal diferem consideravelmente daquelas observadas no carcinoma epidermóide, evidenciando o quão distintas são estas duas doenças.

Cytogenetic damage of oral mucosa by consumption of alcohol, tobacco and illicit drugs

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

Estudo morfológico da polpa de molares de ratos Wistar frente a uma oclusão traumática experimental

As alterações morfológicas pulpares, decorrentes de um estímulo externo experimental (interferência oclusal), foram estudadas, em nível de microscopia de luz. Utilizaram-se restaurações de amálgama, em sobreoclusão nos primeiros molares superiores direitos de dez ratos Wistar, divididos em 3 grupos e sacrificados por perfusão transcardíaca com formol a 10%, aos 10, 20 e 30 dias. A avaliação foi feita nos molares inferiores direitos (lado experimental) e esquerdos (lado controle). As peças ósseas após descalcificação em solução de EDTA associada às microondas, seguiram técnica histológica de rotina e coloração por hematoxilina-eosina e tricrômico de Mallory. Verificou-se no lado controle uma reação intensa caracterizada por um posicionamento atípico dos odontoblastos, seguida pelo aparecimento de cálculos pulpares e posteriormente por uma aparente e uniforme acomodação tecidual em toda a polpa, com moderada incidência de fibras colágenas. No lado experimental, as alterações foram similares parecendo, porém, aumentar com o tempo, principalmente aos 30 dias, onde a imagem histológica era semelhante à do lado controle aos 10 dias. Os resultados obtidos permitiram concluir que a interferência oclusal provocou alterações no tecido conjuntivo pulpar tanto no lado experimental como no controle e que as mesmas foram proporcionais à direção dos movimentos mandibulares.

Effect of annealing time on morphological characteristics of Ba(Zr,Ti)O-3 thin films

Ba(Zr0.50Ti0.50)O-3 thin films were prepared by the polymeric precursor method using the annealing low temperature of 300 degrees C for 8, 16, 24, 48, 96 and 192 It in a furnace tube with oxygen atmosphere. The X-ray diffraction patterns revealed that the film annealed for 192 h presented some crystallographic planes (1 0 0), (1 1 0) and (2 0 0) in its crystalline lattice. Fourier transformed infrared presented the formation of metal-oxygen stretching at around 756 cm(-1). The atomic force microscopy analysis presented the growth of granules in the Ba(Zr0.50Ti0.50)O-3 films annealed from 8 to 96 h. The crystalline film annealed for 192 h already presents grains in its perovskite structure. It evidenced a reduction in the thickness of the thin films with the increase of the annealing time. (C) 2006 Elsevier B.V. All rights reserved.

Relationship between structural features and in vitro release of doxorubicin from biocompatible anionic microemulsion

In this work structural features of anionic microemulsions, containing the pharmaceutical biocompatible components soya phosphatidylcholine (SPC), eumulgin HRE 40 (EU) and sodium oleate (SO) as surfactant, cholesterol (CHO) as oil phase and aqueous buffer were studied. Microemulsions were formulated with and without the antitumor drug doxorubicin (DOX). The various microstructures characterized in the pseudo-temary phase diagram were analyzed by polarized light microscopy, small-angle X-ray scattering (SAXS) and X-ray diffraction (XRD) as well as by their ability to incorporate and release DOX. The experimental results demonstrated a correlation between the composition, the structural features and drug delivery. It was found that at higher cholesterol contents, the crystallization of CHO polymorph phases changed the mobility of DOX molecules. Droplets were formed with short-range spatial correlation from a microemulsion (ME) with a low surfactant:oil ratio. More ordered structures with lamellar arrangements formed by the increasing of the CHO proportions in the formulation may be due to CHO crystallization. The in vitro release of DOX showed that the presence of a high content of crystalline CHO prolongs the release of DOX from ME. The retention of DOX in the internal oil phase of the ME may modulate the drug release for a prolonged time. These results clearly demonstrate the potential of ME as a drug-delivery system. (c) 2007 Elsevier B.V. All rights reserved.