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  • Open Access

    ARTICLE

    Effects of plow pan on SPAD value and chloroplast ultrastructure in leaves of spring maize

    Li G, FT Yang, XL Jiang, FX Chen, TH Cao, LC Wang

    Phyton-International Journal of Experimental Botany, Vol.82, pp. 243-247, 2013, DOI:10.32604/phyton.2013.82.243

    Abstract The aim of this study was to evaluate the impact of the plow pan on the production of spring corn. We evaluated SPAD values and chloroplast ultrastructure in premature ear leaves of spring maize at the grain-filling stage. The maize plants were grown in simulated plow pan or simulated subsoiling treatments. Plants in the simulated plow pan treatment showed irreversible damage to chloroplasts, including changes in chloroplast shape, disintegration and rupture of chloroplast membranes, and blurriness and cloudiness of grana lamellae. The chlorophyll content decreased, which is a typical characteristic of senescence. Subsoiling cultivation practices resulted in chloroplasts with a… 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 treatment. The Aluminum… 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 a specialized zone of… 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 spread around the… 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 -, pigment-, and retinula cells are… 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 of myofilaments that are… 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. Taking into account… 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 in the lateral membranes of… More >

  • Open Access

    ABSTRACT

    Minireview: Oviductal structure and provision of egg envelops in the apple snail Pomacea canaliculata (Gastropoda, Prosobranchia, Ampullariidae)

    N.M.Y. Catalán, S.N. Fernández, B.C. Winik

    BIOCELL, Vol.26, Suppl.S, pp. 91-100, 2002

    Abstract This article has no abstract. More >

  • Open Access

    ARTICLE

    An ultrastructural study of spermiogenesis in two species of Sitophilus (Coleoptera: Curculionidae)

    KHESLLER PATRÍCIA OLÁZIA NAME, GIULIANO PAGY FELIPE DOS REIS, SÔNIA NAIR BÁO

    BIOCELL, Vol.31, No.2, pp. 229-236, 2007, DOI:10.32604/biocell.2007.31.229

    Abstract The spermiogenesis of Sitophilus zeamais and Sitophilus oryzae, the maize and the rice weevil, respectively, was studied by light microscopy and scanning and transmission electron microscopy. Sitophilus spp. is the most widespread and destructive primary pest of stored cereals in the world. The spermiogenesis occurs within cysts. There are approximately 256 germ line cells per cyst. Inside each cysts, all the spermatids are in the same stage of maturation. The ultrastructure of the spermatozoa of S. zeamais and S. oryzae is similar to that described for other beetles. The head is formed by a three-layered acrosome with the perforatorium, the… More >

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