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  • Open Access

    ARTICLE

    Protein detection in spermatids and spermatozoa of the butterfly Euptoieta hegesia (Lepidoptera)

    KARINA MANCINI, HEIDI DOLDER

    BIOCELL, Vol.28, No.3, pp. 299-310, 2004, DOI:10.32604/biocell.2004.28.299

    Abstract This study was undertaken to detect protein components in both sperm types of the butterfly Euptoieta hegesia. These spermatozoa possess complex extracellular structures for which the composition and functional significance are still unclear. In the apyrene sperm head, the proteic cap presented an external ring and an internal dense content; basic proteins were detected only in external portions. In the tail, the paracrystalline core of mitochondrial derivatives and the axoneme are rich in proteins. The extratesticular spermatozoa are covered by a proteic coat, which presented two distinct layers. In eupyrene spermatozoa, acrosome and nucleus were negatively… More >

  • Open Access

    ARTICLE

    Brief Note: Ultrastructure of the Lyonet’s glands in larvae of Diatraea saccharalis Fabricius (Lepidoptera: Pyralidae)

    ELIANE VICTORIANO, ELISA A. GREGÓRIO

    BIOCELL, Vol.28, No.2, pp. 165-169, 2004, DOI:10.32604/biocell.2004.28.165

    Abstract The Lyonet’s gland is found in Lepidoptera larvae, close to the excretory duct of the silk gland. The role played by this gland is still uncertain. This work aims to describe the ultrastructure of the Lyonet’s gland in Diatraea saccharalis larvae, offering suggestions regarding its possible function. The insects were reared under laboratory-controlled conditions. The glands were conventionally prepared for transmission (TEM) and scanning (SEM) electron microscopy. SEM showed that Lyonet’s glands are paired small structures located in the ventral side of the head. They are composed by clustered long cells resembling leaves. Under TEM observations,… More >

  • Open Access

    ARTICLE

    Sperm ultrastructure and spermatogenesis in the lizard, Tropidurus itambere

    ADELINA FERREIRA, HEIDI DOLDER

    BIOCELL, Vol.27, No.3, pp. 353-362, 2003, DOI:10.32604/biocell.2003.27.353

    Abstract Spermatogenesis, with emphasis on spermiogenesis, is described for the lizard, Tropidurus itambere, using light microscopy, phase contrast and epifluorescence, as well as scanning and transmission electron microscopy. Cellular differentiation involves events of chromatin condensation, nuclear elongation and the formation of structural complexes, such as the acrosomal and axonemal ones. Other new characteristics, exclusive for this species, include various aspects of the subacrosomal granule, the insertion of the proacrosomal vesicle and the development of these structures to participate in the acrosomal complex. Radial projections occur just above the nuclear shoulders, which have been recognized already from the More >

  • Open Access

    ARTICLE

    Ultrastructural effects of two phthalocyanines in CHO-K1 and HeLa cells after laser irradiation

    Marcelo de Castro Pazos*, Cristina Pacheco-Soares*, Newton Soares da Silva*, R.A. DaMatta**, M.T.T. Pacheco*

    BIOCELL, Vol.27, No.3, pp. 301-309, 2003, DOI:10.32604/biocell.2003.27.301

    Abstract The effects of Photodynamic Therapy using 2nd generation photosensitizers have been widely investigated aiming clinical application treatment of solid neoplasms. In this work, ultrastructure changes caused by the action of two 2nd generation photosensitizers and laser irradiation on CHO-K1 and HeLa (neoplastic) cells were analyzed by transmission electron microscopy. Aluminum phthalocyanine chloride, aluminum phthalocyanine tetrasulfonate chloride and radiation from a semiconductor laser at a fluency of 0.5 J/ cm2 (Power=26mW; λ=670nm) were used. The results showed induction of apoptosis. Such alterations where observed in HeLa but not in CHO-K1 cells after Aluminum phthalocyanine tetrasulfonate chloride (AlPcS4) photodynamic More >

  • Open Access

    ARTICLE

    Structure of the kidney of Bufo arenarum: Intermediate segment, distal tubule and collecting tubule

    A. Farías, G.N. Hermida, L.E. Fiorito

    BIOCELL, Vol.27, No.1, pp. 19-28, 2003, DOI:10.32604/biocell.2003.27.019

    Abstract The ultrastructure of the intermediate segment (IS), distal tubule and collecting tubule (CT) of the south american toad Bufo arenarum, was studied by light and transmission electron microscopy. The IS is composed of cubical ciliated cells which propel the urine along the renal tubule. The distal tubule is divided into two portions: the early distal tubule (EDT) and the late distal tubule (LDT). The EDT is characterized by only one type of cells with well developed basolateral interdigitations and numerous elongated mitochondria, which are oriented normal to the basal surface. The “macula densa - like” is… More >

  • Open Access

    ARTICLE

    Ultrastructural characteristics of the lung of Melanophryniscus stelzneri stelzneri (Weyenberg, 1875) (Anura, Bufonidae)

    GLADYS N. HERMIDA, ALEJANDRO FARÍAS, LUISA E. FIORITO

    BIOCELL, Vol.26, No.3, pp. 347-355, 2002, DOI:10.32604/biocell.2002.26.347

    Abstract The lung of the toad, Melanophryniscus stelzneri stelzneri was studied using scanning and transmission electron microscopy. In M.s.stelzneri the parenchyma forms a polygonal network arrangement, therefore the parenchyma is edicular. These spaces are delimited by the interconnection of third order septa which are covered by respiratory epithelium. Small patches of ciliated epithelium without goblet cells appear irregularly distributed on the septa. The respiratory epithelium consists of one type of pneumocyte, which shows characteristics of both type I and type II alveolar cells of higher vertebrates. The pneumocytes are irregular in shape and possess attenuated cytoplasmic processes, which… More >

  • Open Access

    ARTICLE

    Microanatomical Characteristics of Marginal Ommatidia in Three Different Size-Classes of the Semi-Terrestrial Isopod Ligia exotica (Crustacea; Isopoda)

    ESSI KESKINEN1 , YASUHARU TAKAKU2 , V. BENNO MEYER-ROCHOW3, TAKAHIKO HARIYAMA4

    BIOCELL, Vol.26, No.3, pp. 357-367, 2002, DOI:10.32604/biocell.2002.26.357

    Abstract The aims of this paper have been (a) to characterize marginal ommatidia from different eye regions through a detailed description of their distinct ultrastructural features in three different size-classes of L. exotica, and (b) to compare microanatomical characteristics of the marginal ommatidia with those of ommatidia of the same eye, but located further centrally. On the basis of transverse as well as longitudinal sections we conclude that new ommatidia are added from a crescentic dorso-anterio-ventral edge of the eye and that maturing ommatidia go through a sequence in which originally the nuclei of cone -,… More >

  • Open Access

    ARTICLE

    Ultrastructure of the ovariole sheath in Diatraea saccharalis (Lepidoptera: Pyralidae)

    DANIELA CARVALHO DOS SANTOS, ELISA APARECIDA GREGÓRIO

    BIOCELL, Vol.26, No.2, pp. 229-235, 2002, DOI:10.32604/biocell.2002.26.229

    Abstract The ultrastructure of the ovariole sheath along the Diatraea saccharalis ovariole was studied by scanning and transmission electron microscopy. Each ovariole is surrounded by an epithelial sheath, a tunica propria and scattered lumen cells. These three components of the ovariole sheath show different ultrastructural features along the ovariole, in the germarium or in the vitellarium; these differences are more evident in the epithelial sheath cells. The epithelial sheath is composed by two layers of cells, the external one running longitudinally and the internal one running circularly in the ovariole. These cells, in vitellarium, present cytoplasmic bundles More >

  • Open Access

    ARTICLE

    Effect of the Lipophilic o-Naphthoquinone CG 10-248 on Rat Liver Mitochondria Structure and Function

    LIDIA M. LOPEZ*, AMANDA PELLEGRINO DE IRALDI*, PATRICIA H. CARRIZO**, MARTA DUBIN**, ANDRÉS O.M. STOPPANI**

    BIOCELL, Vol.26, No.2, pp. 237-245, 2002, DOI:10.32604/biocell.2002.26.237

    Abstract CG 10-248 (3,4-dihydro-2,2 dimethyl-9-chloro-2H-naphtho[1,2b]pyran-5,6-dione), a ß-lapachone analogue, modified the ultrastructure of rat liver mitochondria in vitro, in the absence of added oxidizable substrates. The condensed mitochondrial state was replaced by the orthodox or swollen state to a significant degree. The number of modified mitochondria depended on incubation time and quinone concentration, in the 25-100 µM range. Under the same experimental conditions, mitochondrial respiration was uncoupled as indicated by the increase in the rate of succinate oxidation by controlled mitochondria in metabolic state “4” (not in state “3”), and by the activation of latent F0 F1 -ATP synthase. More >

  • Open Access

    ARTICLE

    Ultrastructural and cytochemical changes in the liver of primary biliary cirrhosis patients

    ARTURO D. JORGE*, LUIS S. GUTIERREZ**, OLIVER JORGE*, MARIO H. BURGOS**

    BIOCELL, Vol.26, No.2, pp. 253-262, 2002, DOI:10.32604/biocell.2002.26.253

    Abstract The aim of this paper is to establish whether there are cytochemical or ultrastructural alterations in the hepatocytes of patients with primary biliary cirrhosis (PBC) at stages I and II compared with the biopsies from individuals with normal liver. Cytochemical technique with ATP as substrate, transmission electron microscopy (TEM) and freeze fracture were used for the studies.
    In the normal liver biopsies the ultrastructural cytochemical localization of the enzymatic activity was clearly shown in the bile canaliculi. In the PBC biopsies, the enzymatic activity is increased in the bile canaliculi and is also present… More >

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