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  • Open Access

    ARTICLE

    Apoptogenic effect of the lipophilic o-naphthoquinone CG 10-248 on rat hepatocytes: light and electron microscopy studies

    Lidia M. Lopez*, Marta Dubin**, Patricia H. Carrizo**, Mario H. Burgos***, Amanda Pellegrino De Iraldi*, Andrés O. M. Stoppani**

    BIOCELL, Vol.27, No.2, pp. 213-224, 2003, DOI:10.32604/biocell.2003.27.213

    Abstract CG 10-248 (3,4-dihydro-2,2-dimethyl-9-chloro-2H-naphtho[1,2b]pyran- 5,6-dione; CG-NQ), a β-lapachone analogue, modified the ultrastructure of rat hepatocytes, as demonstrated by light and electron microscopy. After 4 h incubation with 100 µM CG-NQ, the following effects were observed: (a) nuclear chromatin condensation; (b) chromatin fragmentation; (c) displacement of mitochondria, concentrated around the nucleus; (d) disruption or expansion of mitochondrial outer or inner membranes, respectively; (e) displacement and alteration of endoplasmic reticulum (rough and smooth); (f) decrease of microvilli; (g) blebbing of plasma membrane and production of apoptotic bodies formed by folding of plasma membrane fragments around mitochondria or peroxysomes; and (h) production of hydrogen… More >

  • Open Access

    ARTICLE

    Micropropagation of Ilex dumosa (Aquifoliaceae) from nodal segments in a tissue culture system

    C. Luna, P. Sansberro*, L. Mroginski, J. Tarragó

    BIOCELL, Vol.27, No.2, pp. 205-212, 2003, DOI:10.32604/biocell.2003.27.205

    Abstract Micropropagation of Ilex dumosa var. dumosa R. (“yerba señorita”) from nodal segments containing one axillary bud was investigated. Shoot regeneration from explants of six-year-old plants was readily achieved in 1/4 strength Murashige and Skoog medium (1/4 MS) plus 30 gr·L-1 sucrose and supplemented with 4.4 µM BA. Further multiplication and elongation of the regenerated shoots were obtained by subculture in a fresh medium of similar composition with 1.5 gr·L-1 sucrose. Rooting induction from shoots were achieved in two steps: 1) 7 days in 1/4 MS (30 gr·L-1 sucrose, 0.25 % Phytagel®) with 7.3 µM IBA and 2) 21 days in… More >

  • Open Access

    ARTICLE

    Defense reactions of Dermatobia hominis (Diptera: Cuterebridae) larval hemocytes

    Ana Carolina Faraldo, Edy Lello

    BIOCELL, Vol.27, No.2, pp. 197-203, 2003, DOI:10.32604/biocell.2003.27.197

    Abstract The defense reactions against biological (Histoplasma capsulatum and Escherichia coli) and non-biological materials (China ink and nylon thread) were tested in vivo in third instar larvae of Dermatobia hominis. The cellular defense performed by larval hemocytes was observed under electron microscopy. China ink particles were phagocytosed by granular cells 5 h after injection. E. coli cells were internalized by granular cells as early as 5 min after injection and totally cleared 180 min post-injection, when many hemocytes appeared disintegrated and others in process of recovering. H. capsulatum yeasts provoked, 24 h after being injected, the beginning of nodule formation. Nylon… More >

  • Open Access

    ARTICLE

    Proteoglycans production by aortic vascular smooth muscle cells from hypertensive rats

    Norma Risler, Claudia Castro, Montserrat Cruzado, Susana González, Roberto Miatello

    BIOCELL, Vol.27, No.2, pp. 189-196, 2003, DOI:10.32604/biocell.2003.27.189

    Abstract Remodeling of large and small arteries contributes to the development and complications of hypertension. Artery structural changes in chronic sustained hypertension include vascular smooth muscle cells (VSMC) proliferation and extracellular matrix (ECM) modifications. Extracellular constituents such as proteoglycans (PGs), may modulate vascular stiffness and VSMC growth and differentiation. We examined the effect of growth factors on secreted and membrane-bound PGs synthesis by cultured aortic smooth muscle cells (SMC) from 12- to 14- week-old spontaneously hypertensive rats (SHR) and age-matched Wistar rats. After stimulation with platelet-derived growth factor (PDGF-BB), 10% fetal calf serum (FCS) or 0.1% FCS as control, PGs synthesis… More >

  • Open Access

    ARTICLE

    Fine structural study of the red seaweed Gymnogongrus torulosus (Phyllophoraceae, Rhodophyta)

    José M. Estevez*, Eduardo J. Cáceres**

    BIOCELL, Vol.27, No.2, pp. 181-187, 2003, DOI:10.32604/biocell.2003.27.181

    Abstract The present study analyzed several characters of the red seaweed Gymnogongrus torulosus, such as cellular structure of the thallus, cuticle, pit plug and cell wall ultrastructure, and morphology of some organelles like plastids, Golgi bodies and mitochondria. Also, anomalous chloroplasts with thylakoid disorganization were found in medullary cells. The significance of this thylakoid disposition is still unclear. This is one of the first studies focused on the fine structure of a red alga recorded in Argentina. More >

  • Open Access

    ARTICLE

    Effect of sugars on the association between cowpea vicilin (7S storage proteins) and fungal cells

    T.L. Rose*, V.M. Gomes*, M. Da Cunha**, K.V.S. Fernandes***, J. Xavier-Filho***

    BIOCELL, Vol.27, No.2, pp. 173-179, 2003, DOI:10.32604/biocell.2003.27.173

    Abstract Vicilins (7S storage proteins) found in various legume seeds have been previously shown to interfere with the germination of spores or conidia of phytopathogenic fungi and inhibit yeast growth and glucose stimulated acidification of the medium by yeast cells. In the present work vicilins from cowpea (Vigna unguiculata) seeds were added to the growth medium of Saccharomyces cerevisiae cells and Fusarium oxysporum conidia. Helix pomatia lectin, wheat germ agglutinin and Ulex europaeus lectin were used to identify differences in the binding of the vicilins to the surface of cells of S. cerevisiae and F. oxysporum treated with this protein. After… More >

  • Open Access

    REVIEW

    Review : Role of mast cells in gastrointestinal mucosal defense

    Alicia B. Penissi*, María I. Rudolph**, Ramón S. Piezzi*

    BIOCELL, Vol.27, No.2, pp. 163-172, 2003, DOI:10.32604/biocell.2003.27.163

    Abstract The purpose of this review, based on studies from our laboratory as well as from others, is to summarize salient features of mast cell immunobiology and to describe their associations with gastrointestinal mucosal defense. Gastrointestinal mast cells are involved in many pathologic effects, such as food hypersensitivity. On the other hand, they also play a protective role in defense against parasitic and microbial infections. Thus, they have both positive and negative effects, but presently the mechanisms that control the balance of these various effects are poorly known. It has been suggested that stabilization of mast cells may be a key… More >

  • Open Access

    ARTICLE

    Interaction of bifidobacteria with the gut and their influence in the immune function

    Gabriela Perdigón1,2, Mónica Locascio1, Marta Medici1, Aida Pesce de Ruiz Holagado1,2, Guillermo Oliver1

    BIOCELL, Vol.27, No.1, pp. 1-9, 2003, DOI:10.32604/biocell.2003.27.001

    Abstract Bifidobacteria are predominant in the lumen of the large intestine and confer various health benefits on the host. They are also used in the preparation of new fermented milks (bioyogurts) or added to conventional yogurt to generate probiotic effects. The colonization of the gut by bacteria tends to be host specific due partly to the way in which bacteria adhere to the intestinal wall. Using a homologous strain of Bifidobacterium animalis in an experimental mouse model, we analyzed by immunofluorescence labelledbacteria and transmission electronic microscopy the importance of this bacterial interaction with epithelial an immune cells associated to the gut,… 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

    Distribution of pectins in the pollen apertures of Oenothera hookeri.velans ster/+ster:

    I.Noher de Halac1,2, I.A. Cismondi2, M.I. Rodriguez-García3, G.Famá

    BIOCELL, Vol.27, No.1, pp. 11-18, 2003, DOI:10.32604/biocell.2003.27.011

    Abstract Cell wall pectins are some of the most complex biopolymers known, and yet their functions remain largely mysterious. The aim of this paper was to deepen the study of the spatial pattern of pectin distribution in the aperture of Oenothera hookeri.velans ster/+ster fertile pollen. We used “in situ” immunocytochemical techniques at electron microscopy, involving monoclonal antibodies JIM5 and JIM7 directed against pectin epitopes in fertile pollen grains of Oenothera hookeri.velans ster/+ster. The same region was also analyzed by classical cytochemistry for polysaccharide detection. Immunogold labelling at the JIM7 epitope showed only in mature pollen labelling mainly located at the intine… More >

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