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  • 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

    Goblet cell number in the ileum of rats denervated during suckling and weaning

    LUZMARINA HERNANDES*, LUCIENI CRISTINA MARQUES DA SILVA PEREIRA*, ELIANA PARISI ALVARES**

    BIOCELL, Vol.27, No.3, pp. 347-351, 2003, DOI:10.32604/biocell.2003.27.347

    Abstract The enteric nervous system plays a role on the stimulation of secretory cells of intestinal epithelia. We have demonstrated that ablation of ENS stimulates epithelial cell proliferation. As goblet cells are important constituents of the epithelial sheet, it is mandatory to investigate separately this cell type. The myenteric plexus of the ileum of rats in postnatal development was partially removed by the serosal application of benzalkonium chloride (BAC). Three groups of animals were used: those where BAC application was at 13 days and sacrifice was at 15 (13/28-day-old) or 23 days after treatment (13/36-day-old), and More >

  • Open Access

    ARTICLE

    A unique mechanism of nuclear division in Giardia lamblia involves components of the ventral disk and the nuclear envelope

    ALBERTO J. SOLARI*, MONICA I. RAHN*, ALICIA SAURA**, HUGO D. LUJAN**

    BIOCELL, Vol.27, No.3, pp. 329-346, 2003, DOI:10.32604/biocell.2003.27.329

    Abstract The fine structure of the binucleate, parasitic protist Giardia lamblia during interphase and divisional stages was studied by serial thin sectioning and three-dimensional reconstructions. The earlier sign of nuclear division is the development of a few peripheral areas of densely packed chromatin directly attached to the inner nuclear envelope. An intracytoplasmic sheet of ventral disk components grows from the cell periphery towards one of the nuclei, apparently constricting this nucleus, which becomes located at a ventral bulge. After the basal bodies become duplicated, a full nuclear division occurs in trophozoites, giving two pairs of parent-daughter nuclei.… More >

  • Open Access

    ARTICLE

    Morphological study of the spermatogenesis in the teleost Piaractus mesopotamicus

    CARMINDA DA CRUZ-LANDIM*, FÁBIO CAMARGO ABDALLA*, MARIA ALICE DA CRUZ-HÖFLING**

    BIOCELL, Vol.27, No.3, pp. 319-328, 2003, DOI:10.32604/biocell.2003.27.319

    Abstract The spermatogenesis of Piaractus mesopotamicus was investigated under light and transmission electron microscopy. The specimens were captured from their natural environment (Rio Miranda and Rio Aquidauana, Pantanal Matogrossense, Brazil) during April and September. The results were compared with the spermatogenic data of specimens under captivity condition. In both conditions, P. mesopotamicus presented the typical spermatogenesis pattern of the teleost fishes, showing no significative differences. The spermatozoon was classified as type I, which has a globular head without acrosome, a short middle piece and a long tail constituted only by the flagellum. This type of spermatozoon is considered More >

  • Open Access

    ARTICLE

    Agrobacterium rhizogenes vs auxinic induction for in vitro rhizogenesis of Prosopis chilensis and Nothofagus alpina

    LUIS A. CARO1, NATALIA SANTECCHIA1, PABLO A. MARINANGELI1, NÉSTOR R. CURVETTO1,2, LUIS F. HERNÁNDEZ1,3

    BIOCELL, Vol.27, No.3, pp. 311-318, 2003, DOI:10.32604/biocell.2003.27.311

    Abstract The induction and improvement of in vitro rhizogenesis of microshoots of Prosopis chilensis (Mol.) Stuntz and Nothofagus alpina (Poep. et Endl. Oerst.) were compared using Agrobacterium rhizogenes (Ar) versus indole-3-butyric acid (IBA) in the culture media. Microshoots of P. chilensis (1-2 cm length), coming from in vitro grown seedlings, were cultivated in a modified Broadleaved Tree Medium (BTMm) containing half salt concentration of macronutrients and 0.05 mg.L-1 benzilaminopurine (BAP). After 30 days, microshoots with 2-4 leaves were selected and cultured in BTMm-agar in presence or abscense of Ar and in combination with IBA. For N. alpina, the apical shoots with the first 2 true… 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

    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; 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%… More >

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