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  • Open Access

    ARTICLE

    Comparative study of DNA synthesis and nucleolar organizer regions of sinusoid littoral cells in mouse regenerating liver

    CARLOS A. MARTÍN, JOSÉ MIGUEL SURUR, MARCELA N. GARCÍA, FÉLIX CORRONS, AMADO F. BADRÁN

    BIOCELL, Vol.29, No.1, pp. 33-38, 2005, DOI:10.32604/biocell.2005.29.033

    Abstract Variations in DNA synthesis (DNAs) and Nucleolar Organizer Regions (NORs) were studied in the littoral cell population from regenerating liver of C3HS inbred mice standardized for periodicity analysis. Immunohistochemical detection of Bromodeoxyuridine (BrdU) with a monoclonal antibody and silver staining of NORs (AgNORs) were assessed by means of a digital image analysis system in histological sections. Tissue samples were obtained every four hours from the 30th to the 54th hours after a partial hepatectomy. The results showed, in both parameters, a gradual increment of the values during the period studied, with highest values (DNAs 107.1 ± 16.1 SE; AgNORs 77.3… More >

  • Open Access

    ARTICLE

    Fine structural analysis of the epithelial cells in the hepatopancreas of Palaemonetes argentinus (Crustacea, Decapoda, Caridea) in intermoult

    LILIANA G. SOUSA1, ELENA I. CUARTAS2, ANA MARÍA PETRIELLA1, 3

    BIOCELL, Vol.29, No.1, pp. 25-31, 2005, DOI:10.32604/biocell.2005.29.025

    Abstract The aim of this study is to describe the ultrastructure of the hepatopancreas of P. argentinus in intermoult. P. argentinus hepatopancreas was studied using standard TEM techniques. Each tubule consists of four cellular types: E (embryonic), F (fibrillar), R (resorptive) and B (blister like). E-cells have embryonic features and some of them were found in mitosis. F, R and B cells possess an apical brush border. F-cells have a central or basal nucleus, a conspicuous RER, and dilated Golgi cisternae. R cells show a polar organization of organelles in three areas: apical, with numerous mitochondria and sER tubules, a central… More >

  • Open Access

    ARTICLE

    Effects of filgrastim on granulopoietic cells of mice pretreated with methotrexate

    LILIAN BARRIOS, OSCAR HÉCTOR POLETTI

    BIOCELL, Vol.29, No.1, pp. 7-14, 2005, DOI:10.32604/biocell.2005.29.007

    Abstract We have evaluated the effect of filgrastim on proliferation and differentiation activity of granulopoietic cells in mice pretreated with methotrexate. Filgrastim was injected daily, from day 8 to 28 after cytotoxic agent administration. The granulopoiesis changes were measured by assessment of GM-CFU cells content, marrow and spleen granuloid cells pool as well as circulating neutrophils. In MTX pretreated mice, bone marrow GM-CFU oscillating values were higher than normal values, but these changes were not followed by high proliferative activity in granuloid precursor cell compartment. After MTX treatment, filgrastim administration was unable to stimulate marrow granulopoiesis as observed in normal mice.… More >

  • Open Access

    ARTICLE

    Comparative study of mandibular glands of Melipona bicolor queens obtained from polygynic and monogynic colonies

    LUCIANA FIORETTI GRACIOLI-VITTI, FÁBIO CAMARGO ABDALLA, REGINA LÚCIA MORELLI SILVA DE MORAES

    BIOCELL, Vol.29, No.1, pp. 1-5, 2005, DOI:10.32604/biocell.2005.29.001

    Abstract The aim of the present study was analyze, by histological and morphometrical studies, mandibular glands of Melipona bicolor queens collected from monogynic and polygynic colonies and compare their level of development. The results showed that the glands of physogastric queens from monogynic colony present a higher level of activity in relation to the queens of polygynic colonies; this is explained by the fact that just a unique queen controls the monogynic colony. In the polygynic colonies, the queens may divide such control to each other. More >

  • Open Access

    ARTICLE

    Brief Note : Proacrosin-acrosin activity in capacitated and acrosome reacted sperm from cryopreserved bovine semen

    M. I. ROSATTI, M. T. BECONI, M. CÓRDOBA

    BIOCELL, Vol.28, No.3, pp. 311-316, 2004, DOI:10.32604/biocell.2004.28.311

    Abstract Acrosin activity is associated with normal fertility in human and bovine spermatozoa. The aim of the study was to determine the variation of the enzyme activity in the proacrosin-acrosin system in capacitated and acrosome reacted cryopreserved bovine sperm. Enzyme activity was assessed spectrophotometrically using N-α-benzoyl-DL-arginine p-nitroanilide (BAPNA) as specific substrate for acrosin at pH 8. Capacitation with heparin and quercitin failed to induce conversion of proacrosin to acrosin. An increase in acrosin activity produced by the presence of progesterone, in a dose-dependent manner, was related with the induction of true acrosome reaction. The total level of acrosin activity registered showed… More >

  • 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 stained, probably because of… More >

  • Open Access

    ARTICLE

    RNA fingerprinting using RAP-PCR identifies an EBAF homologue mRNA differentially expressed in rat oviduct

    PABLO A. VALDECANTOS, MARTÍN E. ARGAÑARAZ, CARLOS M. ABATE, DORA C. MICELI

    BIOCELL, Vol.28, No.3, pp. 287-297, 2004, DOI:10.32604/biocell.2004.28.287

    Abstract As a step towards the identification of genes preferentially expressed in the oviduct during early rat embryo development, we isolated a cDNA fragment (Pr14) by using RNA arbitrarily primed PCR (RAP-PCR), being its expression restricted to oviduct and uterus; its mRNA is mainly expressed in oviduct during late luteal phase and early pregnancy. This fragment is 100% identical to a rat DNA sequence (Accession No. NW_047400) downstream the terminal exon of a Rattus norvegicus gene (Locus Link Accession No. LOC289316) similar to ebaf (endometrial bleeding-associated factor), a novel member of the Transforming Growth Factor superfamily. Northern analyses showed that this… More >

  • Open Access

    ARTICLE

    Karyotype description of Pomacea patula catemacensis (Caenogastropoda, Ampullariidae), with an assessment of the taxonomic status of Pomacea patula

    MARÍA ESTHER DIUPOTEX-CHONG1, NÉSTOR J. CAZZANIGA2, ALEJANDRA HERNÁNDEZ-SANTOYO3, JOSÉ MIGUEL BETANCOURT-RULE4

    BIOCELL, Vol.28, No.3, pp. 279-285, 2004, DOI:10.32604/biocell.2004.28.279

    Abstract Mitotic chromosomes of the freshwater snail Pomacea patula catemacensis (Baker 1922) were analyzed on gill tissue of specimens from the type locality (Lake Catemaco, Mexico). The diploid number of chromosomes is 2n = 26, including nine metacentric and four submetacentric pairs; therefore, the fundamental number is FN = 52. No sex chromosomes could be identified. The same chromosome number and morphology were already reported for P. flagellata, i.e., the other species of the genus living in Mexico. The basic haploid number for family Ampullariidae was reported to be n° =°14 in the literature; so, its reduction to n° =°13 is… More >

  • Open Access

    ARTICLE

    Microcutting culture and morpho-physiological changes during acclimation in two Lycium chilense cytotypes

    PABLO HORACIO MASEDA1, JORGE HUGO LEMCOFF1, MERCEDES MURÚA2, NORA FRAYSSINET3, MARTA SUSANA CARCELLER1†

    BIOCELL, Vol.28, No.3, pp. 271-277, 2004, DOI:10.32604/biocell.2004.28.271

    Abstract Lycium chilense, a deciduous perennial shrub, is one of the endangered native species of Patagonia due to sheep overgrazing. Chances of recolonization by seeds are scarce due to the limited density of propagules in the soil and very specific requirements for germination. The objective was to develop an in vitro propagation protocol that would help to perform reestablishment of this species in degraded areas of the Patagonian steppe. Seeds came from two provenances with different somatic number due to differences in ploidy level. Defoliated microcuttings were planted in test tubes with different growing media and taken to a growth chamber.… More >

  • Open Access

    ARTICLE

    Differentiation and morphogenesis of Triatoma infestans (Klug 1834) female gonads. I – Post embryonic development

    CECILIA I. IBAÑEZ DE BARRETT, JUAN PABLO BOZZINI, MARTA MARIANO DE BOZZINI*

    BIOCELL, Vol.28, No.3, pp. 259-269, 2004, DOI:10.32604/biocell.2004.28.259

    Abstract The post-embryonic development of the female gonads in Triatoma infestans (Hemiptera, Heteroptera), insects of importance in health affairs as harbors and vectors of different tripanosomatidea flagellates, is presented in a complete follow-up since insect hatches from the egg up to the last molt in the fifth instar stage. The detailed description of the morphological changes which occur in each instar as well as careful measurements evaluating its size increase have been analyzed by stereomicroscopy, phase contrast, dark field, and oblique illumination, in order to optimize the observations as well the photographic register of gonad morphology and structure.
    The analysis… More >

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