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  • Open Access

    ARTICLE

    Ubisch bodies and pollen ontogeny in Oxalis articulata Savigny

    SONIA ROSENFELDT, BEATRIZ G. GALATI

    BIOCELL, Vol.29, No.3, pp. 271-278, 2005, DOI:10.32604/biocell.2005.29.271

    Abstract The correlation between the ontogeny of Ubisch bodies and pollen development in Oxalis articulata was studied with Transmission Electron Microscopy (TEM). The ultrastructural changes observed during the different stages of development in the tapetal cells are related to Ubisch bodies, sporopollenin and pollen-kitt formation. The pro-orbicules have the appearance of lipid globuli and their formation is related to the endoplasmic reticulum of rough type (ERr). The lipid globules or pro-orbicules disappear in the mature Ubisch bodies, and the places that they occupied remain free of contents or with pollen-kitt. More >

  • Open Access

    ARTICLE

    Extracellular breakdown of collagen by mice decidual cells. A cytochemical and ultrastructural study

    SIMA GODOSEVICIUS KATZ

    BIOCELL, Vol.29, No.3, pp. 261-270, 2005, DOI:10.32604/biocell.2005.29.261

    Abstract The interaction of antimesometrial decidual cells and collagen fibrils was studied by light microscopy and ultrastructural cytochemistry in fed and acutely fasted mice on days 9-11 of pregnancy.
    Fibrillar elements in the extracellular space consisted of collagen fibrils and filamentous aggregates (disintegrating collagen fibrils). Intracellular vacuoles exhibited typical collagen immersed in electron-translucent material (clear vacuoles) and faint cross-banded collagen immersed in electron-opaque material (dark vacuoles).
    Fibrillar elements showed extracellular acid phosphatase activity which was stronger in the region of mature decidua than in predecidual cells region in all animals; it was conspicuous in mature… More >

  • Open Access

    ARTICLE

    Construction and application of a yeast expression system for thymosin α1

    CHEN FENG*, CHEN XIANG-MING**, CHEN ZHI*, JIANG HAN-LIANG*, PAN XIAO-PING*, HU ZHONG-RONG*, LIU RONG-HUA*, CHEN XIAO-MING*

    BIOCELL, Vol.29, No.3, pp. 253-259, 2005, DOI:10.32604/biocell.2005.29.253

    Abstract We want to construct a yeast expression system for thymosin α1 (Tα1) to make the orally administered Tα1 preparation possible. The whole Tα1 DNA fragment was obtained by PCR. After being digested with restriction enzymes, it was cloned into pYES2 vector. Sequencing was performed to identify the recombinant. The sequence of Tα1 in recombinant coincided with the original one reported in Genbank. When pYES2-Tα1 plasmid was transformed into yeast, galactose instead of glucose was used to induce Tα1 expression. Western blot was performed to identify the quality of the expressed Tα1. Dried yeast containing pYEST2-Tα1… More >

  • Open Access

    ARTICLE

    Seasonal variations in the heterologous binding of viscacha spermatozoa. A scanning electron microscope study

    CLAUDIA AGUILERA MERLO, ESTELA MUÑOZ, SUSANA DOMINGUEZ, MABEL FÓSCOLO*, LUIS SCARDAPANE, JUAN CARLOS DE ROSAS*

    BIOCELL, Vol.29, No.3, pp. 243-251, 2005, DOI:10.32604/biocell.2005.29.243

    Abstract Seasonal changes in the reproductive activity of the adult male viscacha (Lagostomus maximus maximus) were investigated during the annual reproductive cycle. Assays of heterologous in vitro binding between compatible gametes were used to evaluate the ability of viscacha spermatozoa to achieve primary binding during its annual reproductive cycle. Sperm were collected by mincing cauda epididymis in HECM-3 medium and the sperm concentration and motility were evaluated. Cumulus-free and zona-free oocytes obtained from superovulated hamsters were inseminated in vitro with capacitated sperm suspensions, incubated at 37ºC, 5% CO2 for 3 h, and then processed for studies by scanning… More >

  • Open Access

    ARTICLE

    Brief Note: Reactive oxygen species in bovine embryo in vitro production

    G.C. DALVIT, P.D. CETICA, L.N. PINTOS, M.T. BECONI

    BIOCELL, Vol.29, No.2, pp. 209-212, 2005, DOI:10.32604/biocell.2005.29.209

    Abstract Oxidative modifications of cell components due to the action of reactive oxygen species (ROS) is one of the most potentially damaging processes for proper cell function. However, in the last few years it has been observed that ROS participate in physiological processes. The aim of this work was to determine ROS generation during in vitro production of bovine embryos. Cumulus-oocyte complexes were recovered by aspiration of antral follicles from ovaries obtained from slaughtered cows and cultured in medium 199 for 22 h at 39ºC in 5% CO2: 95% humidified air. In vitro fertilization was carried out in… More >

  • Open Access

    ARTICLE

    Brief Note: Natural infection of Viola cornuta (Violaceae) with Cucumber mosaic virus, subgroup I

    JOEL ARNEODO*, SOLEDAD DE BREUIL*, SERGIO LENARDON**, LUIS CONCI**

    BIOCELL, Vol.29, No.2, pp. 205-207, 2005, DOI:10.32604/biocell.2005.29.205

    Abstract Plants of Viola cornuta displaying typical virus symptoms were observed during spring 2003 in a plant nursery in Córdoba, central Argentina. Electron microscopic examinations of symptomatic leaf samples revealed the presence of isometric virus-like particles about 30 nm in diameter. Subsequent serological analysis allowed the identification of the pathogen as a subgroup I strain of Cucumber mosaic virus (CMV). These results were confirmed by antigen capture - reverse transcription - polymerase chain reaction with specific CMV primers, and digestion with a restriction enzyme. This is the first report of CMV infecting V. cornuta in Argentina. More >

  • Open Access

    ARTICLE

    Changes in crossover distribution along a quadrivalent in a man carrier of a reciprocal translocation t(11;14)

    M.I. PIGOZZI, R.B. SCIURANO, A.J. SOLARI

    BIOCELL, Vol.29, No.2, pp. 195-203, 2005, DOI:10.32604/biocell.2005.29.195

    Abstract A testicular biopsy from an infertile man carrying a heterozygous chromosome translocation t(11;14) was studied with synaptonemal complex analysis and immunolocalization of the protein MLH1 for crossover detection. A full blockage of spermatogenesis at the spermatocyte stage was related to the presence of the translocation quadrivalents at pachytene. Only 2% of the quadrivalents showed full synapsis. Most of the spermatocytes showed asynaptic free ends that frequently mingled with the XY pair. The average number of crossovers per cell was diminished from a mean of 52.7 in controls to a mean of 48 in the patient. More >

  • Open Access

    ARTICLE

    Molecular cloning and characterization of a novel mannosebinding lectin cDNA from Zantedeschia aethiopica

    ZHONGHAI CHEN1, YONGZHEN PANG1, XIAOJUN LIU1, XINGLONG WANG1, ZHONGXIANG DENG1, XIAOFEN SUN1, KEXUAN TANG1,2

    BIOCELL, Vol.29, No.2, pp. 187-193, 2005, DOI:10.32604/biocell.2005.29.187

    Abstract Using RNA extracted from Zantedeschia aethiopica young leaves and primers designed according to the conservative regions of Araceae lectins, the full-length cDNA of Z. aethiopica agglutinin (ZAA) was cloned by rapid amplification of cDNA ends (RACE). The full-length cDNA of zaa was 871 bp and contained a 417 bp open reading frame (ORF) encoding a lectin precursor of 138 amino acids. Through comparative analysis of zaa gene and its deduced amino acid sequence with those of other Araceae species, it was found that zaa encoded a precursor lectin with signal peptide. Secondary and three-dimensional structure analyses showed that ZAA More >

  • Open Access

    ARTICLE

    Regulation of mouse embryo development by autocrine throphic factors

    M.T. TERUEL1,2, R.C. CATALANO2, J.A. CABODEVILA2, S.S. CALLEJAS2

    BIOCELL, Vol.29, No.2, pp. 183-186, 2005, DOI:10.32604/biocell.2005.29.183

    Abstract Embryo development depends on maternal and embryonic factors. When occurs in vitro, embryos secrete factors that stimulate their development. The purpose of this study was to investigate the possible effects of embryos at morula stage on mouse embryo development in vitro. To obtain conditioned media (CM), morulas were cultured in groups of 5 (CM5) or 10 (CM10) in microdrops of Ham-F10 culture medium during 24 h and later they were removed. Subsequently, 365 morulas were cultured in CM5 and CM10 or in Ham-F10 media (as control group). No differences in blastocyst formation could be found between embryos… More >

  • Open Access

    ARTICLE

    A male-sterile mutation in soybean (Glycine max) affecting chromosome arrangement in metaphase plate and cytokinesis

    NILTON CESAR PIRES BIONE1, MARIA SUELY PAGLIARINI2, LEONES ALVES DE ALMEIDA3

    BIOCELL, Vol.29, No.2, pp. 177-181, 2005, DOI:10.32604/biocell.2005.29.177

    Abstract A spontaneous male-sterile, female-fertile mutation affecting bivalent arrangement at the metaphase plate and cytokinesis was detected in line BR98-197 of the soybean breeding program developed by Embrapa – National Soybean Research Centre. Untill diakinesis, meiosis was normal with chromosome pairing as bivalents. From this phase, in several meiocytes, bivalents were not able to organize a single metaphase plate and remained scattered in the cytoplasm in a few or several groups. In these meiocytes, chromosomes segregated in both divisions giving rise to several micronuclei. However, the main cause of male sterility was the absence of cytokinesis More >

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