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  • 1
    Electronic Resource
    Electronic Resource
    Localization of ATPase in the endoplasmic reticulum and golgi apparatus of barley aleurone (1987)
    Springer
    Protoplasma 138 (1987), S. 73-88 
    Details
    ISSN: 1615-6102
    Keywords: ATPase ; Barley aleurone ; Endoplasmic reticulum ; Gibberellic acid ; Golgi apparatus ; Secretion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The cytochemical localization of adenosine triphosphatase (ATPase) was studied in the aleurone layer of barley (Hordeum vulgare L. cv. Himalaya). Isolated barley aleurone layers secrete numerous enzymes having acid phosphatase activity, including ATPase. The secretion of these enzymes was stimulated by incubation of the aleurone layer in gibberellic acid (GA3). ATPase was localized using the metal-salt method in tissue incubated in CaCl2 with and without GA3. In sections of tissue incubated without GA3, cytochemical staining was confined to a narrow band of cytoplasm adjacent to the starchy endosperm and to the cell wall of the innermost tier of aleurone cells. Cytochemical staining was absent from the organelles of tissues not treated with GA3. In tissue incubated in the presence of GA3, cytochemical staining was evident throughout the cytoplasm and cell walls of the tissue. In the cell wall, electron-dense deposits were found only in digested channels. The cell-wall matrix of GA3-treated aleurone did not stain, indicating that it does not permit diffusion of enzyme. In the cytoplasm of GA3-treated aleurone, all organelles except microbodies, plastids, and spherosomes stained for ATPase activity; endoplasmic reticulum (ER), Golgi apparatus, and mitochondria showed intense deposits of stain. The ER of the aleurone is a complex system made up of flattened sheets of membrane, which may be associated with both the Golgi apparatus and the plasma membrane. The dictyosome did not stain uniformly for ATPase activity; rather there was a gradation in staining of the cisternae from thecis (lightly stained) to thetrans (heavily stained) face. Vesicles associated with dictyosome cisternae also stained intensely as did the protein bodies of GA3-treated aleurone cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01281016
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  • 2
    Electronic Resource
    Electronic Resource
    Localization of α-amylase isozymes within the endomembrane system of barley aleurone (1990)
    Springer
    Protoplasma 154 (1990), S. 16-24 
    Details
    ISSN: 1615-6102
    Keywords: α-Amylase isozymes ; Barley aleurone ; Endoplasmic reticulum ; Golgi apparatus ; Immunocytochemistry ; Intracellular transport
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The localization of α-amylase (EC 3.2.1.1) in barley (Hordeum vulgare L. cv Himalaya) aleurone protoplasts was studied using electron microscope immunocytochemistry. Antibodies were raised against total barley α-amylase, i.e., α-amylase containing both highisoelectric point (high-pI) and low-pI isoforms, as well as against purified high- and low-pI isoforms. All antibodies localized α-amylase to the endoplasmic reticulum (ER) and Golgi apparatus (GApp) of the aleurone cell, and various controls showed that the labeling was specific for α-amylase. Labeling of protein bodies and spherosomes, which are the most abundant organelles in this cell, was very low. There was no evidence that α-amylase isoforms were differentially distributed within different compartments of the endomembrane system. Rather, both high- and low-pI isoforms showed the same pattern of distribution in ER and in the cis, medial, and transregions of the GApp. We conclude that in the Himalaya cultivar of barley, all isoforms of α-amylase are transported to the plasma membrane via the GApp.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01349531
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  • 3
    Electronic Resource
    Electronic Resource
    Estimating viability of plant protoplasts using double and single staining (1986)
    Springer
    Protoplasma 135 (1986), S. 80-87 
    Details
    ISSN: 1615-6102
    Keywords: Barley aleurone ; Fluorescein diacetate ; Propidium iodide ; Protoplasts ; Viability determination ; Vital stains
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The utility of numerous dyes for determining the viability of barley (Hordeum vulgare L. cv. Himalaya) aleurone protoplasts was studied. Protoplasts isolated from the barley aleurone layer synthesize and secrete α-amylase isozymes in response to treatment with gibberellic acid (GA) and Ca2+. These cells also undergo dramatic morphological changes which eventually result in cell death. To monitor the viability of protoplasts during incubation in GA and Ca2+, several types of fluorescent and nonfluorescent dyes were tested. Evans blue and methylene blue were selected as nonfluorescent dyes. Living cells exclude Evans blue, but dead cells and cell debris stain blue. Both living and dead cells take up methylene blue, but living cells reduce the dye to its colorless form whereas dead cells and cell debris stain blue. The relatively low extinction coefficient of these dyes sometimes makes it difficult to distinguish blue-stained cells against a background of blue dye. Several types of fluorescent dyes were tested for their ability to differentially stain dead or living cells. Tinopal CBS-X, for example, stains only dead cells, and its high extinction coefficient allows its ultraviolet fluorescence to be recorded even when preparations are simultaneously illuminated with visible light. To double-stain protoplasts, the most effective stain was a combination of fluorescein diacetate (FDA) and propidium iodide (PI). By employing a double-exposure method to record the fluorescence from cells stained with both FDA and PI, dead and living cells could be distinguished on the basis of fluorochromasia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01277001
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  • 4
    Electronic Resource
    Electronic Resource
    Phenytoin-induced connective tissue growth in the rat (1986)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 215 (1986), S. 99-105 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Rats were treated daily for 9 days with 100, 50, or 25 mg/kg phenytoin i.p. This treatment resulted in a significant increase in the thickness of the connective tissue capsules of the liver, spleen, and pancreas, and of the subepithelial connective tissue of the mesentery but not the epicardium or visceral pleura of the lung where exposure to the drug was via the vascular route. Many areas of connective tissue growth exhibited obvious proliferation of fibroblasts and in some areas contained seemingly large numbers of macrophages and an increase in vascularity. It was demonstrated by electron microscopy that the macrophages occasionally were seen in intimate contact with the fibroblasts.Our observations clearly showed that intraperitoneal exposure of visceral connective tissues of the rat to phenytoin rapidly resulted in a dose-related proliferation of that tissue. The presence of numerous macrophages leads to the suggestion that macrophage-derived growth factor could be responsible for the increased growth.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1092150203
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  • 5
    Electronic Resource
    Electronic Resource
    Intracellular signal transduction mechanisms of rat epididymal spermatozoa and their relationship to motility and metabolism (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 38 (1994), S. 77-84 
    Details
    ISSN: 1040-452X
    Keywords: Cauda epididymidis ; Sperm activation ; Calcium ions ; Guanylate cyclase ; Adenylate cyclase ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The role of intracellular signal transduction mechanisms in regulating the motility and metabolism of rat spermatozoa in undiluted caudal epididymal fluid (CEF) was examined. Samples of CEF containing immotile spermatozoa were exposed to drugs and other agents that either stimulate signal transduction pathways or mimic the action of their second messengers. Under these conditions, sperm motility in 25-30 nl of CEF was stimulated by calcium ions (Ca2+), N,2′ -O-dibutyryl-guanosine 3′:5′ -cyclic monophosphate (dibutryl cGMP), cyclic adenosine 3′:5′-monophosphate (cAMP), N6,2′-O-dibutyryladenosine 3′:5′ -cyclic monophosphate (dibutyryl cAMP), 8-bromoadenosine 3′:5′ -cyclic monophosphate (8-bromo cAMP), caffeine, theophylline and bicarbonate ions (HCO3-). Other agents such as magnesium ions (Mg2+), veratridine, phospholipase C (PLC), ionophore A23187, 1,2-dioctenoyl-sn-glycerol (DAG), phorbol 12-myristate 13-acetate, phospholipase A2 (PLA2), arachidonic acid, and melittin did not significantly influence motility. In the presence of radiolabelled energy substrates, untreated (immotile) spermatozoa in samples of CEF utilised D-[U-14C]glucose and [1-14C]acetate as exogenous energy sources for oxidative metabolism. No detectable 14C-lactate was produced, and none of the drugs altered the rate of glycolytic or oxidative metabolism. The findings suggest that the motility of rat caudal epididymal spermatozoa is regulated by Ca2+ and the guanylate cyclase and adenylate cyclase pathways, but not through the PLC and PLA2 pathways. Also, their metabolism of exogenous substrate was uncoupled from the induction of motility, and their oxidative capacity exceeded the rate of flux of glucose-carbon through the glycolytic pathway. © 1994 Wiley-Liss, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1080380113
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  • 6
    Electronic Resource
    Electronic Resource
    Characterization of low Mr Zona Pellucida binding proteins from boar spermatozoa and seminal plasma (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 33 (1992), S. 108-115 
    Details
    ISSN: 1040-452X
    Keywords: Zona binding proteins ; Seminal plasma ; Fertilization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A group of low Mr (16 kDa - 23 kDa) glycoproteins on ejaculated boar spermatozoa have been shown to have high affinity for homologous zona pellucida glycoproteins (ZPGPs). These ZPGP binding proteins are derived from seminal plasma as shown by their absence from epididymal spermatozoa and their presence in seminal plasma as identified by N-terminal amino acid sequence analysis. They bind to ZPGPs by a polysulphate recognition mechanism similar to that found for proacrosin-ZPGP interactions. The haemagglutination activity of boar seminal plasma is also associated with these low Mr glycoproteins. It is suggested that they play a role in regulating the rate of sperm capacitation and survival in the female reproductive tract. © 1992 Wiley-Liss, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1080330115
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  • 7
    Electronic Resource
    Electronic Resource
    Antigens on rat spermatozoa with a potential role in fertilization (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 25 (1990), S. 286-296 
    Details
    ISSN: 1040-452X
    Keywords: Monoclonal antibodies ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Eight monoclonal antibodies (McAbs), directed against antigens on rat cauda epididymal spermatozoa, were tested for their capacity to interfere with fertilization in vitro as a means of identifying molecules a potential role in sperm-egg recognition and fusion. Antigens recognized by the McAbs were visualized on live spermatozoa by indirect immunofluorescence (IIF) and characterized by immunoblotting. Five McAbs (designated 1B5, 2C4, 4B5, 5B1, and 8C4) recognized antigens specifically on the sperm acrosome and three (designated 2B1, 2D6, and 6B2) bound to the flagellum. Of the eight McAbs investigated, three (2B1, 2C4, and 6B2) were effective in blocking fertilization in vitro when added as culture supernalants to mixtures of sperm and eggs. McAb 6B2 was inhibitory due to its ability to agglutinate spermatozoa. McAbs 2B1 and 2C4 did not agglutinate capacitated spermatozoa, had no observable effect on motility, and yet blocked fertilization in a dose-dependent manner. McAb 2C4 did not give a reaction on immunoblots, but the 2B1 antigen was identified as an Mr 40 kD glycoprotein. McAb 2B1 appeared to block fertilization at the level of zona binding, whereas the effects of 2C4 were directed more against zone penetration and/or fusion with the vitellus. When sperm-egg complexes were stained with 2C4 or 2B1 McAbs and viewed by IIF, all spermatozoa that were attached to the zona showed fluorescence on the head. These results suggest that different antigens on the rat sperm head participate in different aspects of the fertilization process and that during capacitation there is either exposure of these antigens or else they migrate to their site of action from the flagellum.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1080250311
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  • 8
    Electronic Resource
    Electronic Resource
    The effects of alterations in the external sodium concentration on human leucocyte sodium and potassium transport in vitro (1981)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 109 (1981), S. 323-332 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Human leucocytes incubated in tissue culture fluid of low-sodium concentration (2 mM; iso-osmolarity maintained with choline chloride) reached a new equlibrium within 1 hour and lost approximately 25% of intracellular potassium and 70% of intracellular sodium. The rate constant for ouabainsensitive sodium efflux fell by more than 50% and the ouabain-insensitive rate constant increased nearly threefold in the low-sodium medium. Total sodium efflux fell in proportion to internal sodium whereas ouabain-insensitive sodium efflux remained unchanged. A reduction in external sodium from 140 to 2 mM was associated with a 75% fall in sodium influx. In the low-sodium medium ouabainsensitive potassium influx exceeded ouabain-sensitive sodium efflux and no ouabain-sensitive potassium efflux could be demonstrated. Ouabain-insensitive potassium influx and that portion of potassium efflux which is dependent on external potassium fell in parallel in low-sodium cells, suggesting reduced activity of a ouabain-insensitive K:K exchange system.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041090216
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  • 9
    Electronic Resource
    Electronic Resource
    Morphology of the epithelium of the extratesticular rete testis, ductuli efferentes and ductus epididymidis of the adult male rabbitResearch supported by USPHS Grants HD-04290 (DWH) and HD-02344 (DWF), by the Ford Foundation (DWF) and by a Milton Fund grant from Harvard University (DWH). (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    American Journal of Anatomy 156 (1979), S. 373-400 
    Details
    ISSN: 0002-9106
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The fine structure of the epithelium lining the extratesticular rete testis, ductuli efferentes and ductus epididymidis of the rabbit has been investigated. In the ductuli efferentes the epithelium is composed of two cell types, principal cells and ciliated cells. The latter cell type is distinguished from principal cells by the presence of cilia projecting into the lumen and the position of the nucleus in the apical half of the cell. Principal cells in this segment are characterized by micropinocytotic vesicles on the surface plasma membrane and a variety of small dense bodies scattered throughout the cytoplasm. In the ductus epididymidis basal cells replace ciliated cells as the second cell type, but differences between various segments of the epididymis are related to the fine structure of the principal cells. In the proximal caput epididymidis (Nicander's region 1) the principal cells are tall with long microvilli. They typically contain a small Golgi apparatus and a cluster of dense bodies adjacent to the nucleus. In the distal caput epididymidis (Nicander's regions 2-5) the apical cytoplasm of principal cells is filled with numerous micropinocytotic vesicles and large multivesicular bodies; these features are interpreted as signs of absorptive activity. The multivesicular bodies are absent from the cytoplasm of principal cells in the corpus epididymidis (Nicander's region 6) and, instead, numerous elements of smooth endoplasmic reticulum, a large Golgi apparatus, lipid droplets and dense bodies characterize principal cells in this segment. Towards the proximal cauda epididymidis (Nicander's region 7), the number of dense bodies (lysosomes) in the cytoplasm increases considerably. In the globose cauda (Nicander's region 8), the principal cells are reduced in height, and in addition to the features described in region 7, are characterized by a concentric array of rough endoplasmic reticulum in the basal cytoplasm. These observations are discussed in relation to the role of the epididymis in promoting the maturation and survival of spermatozoa.
    Additional Material: 28 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aja.1001560307
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  • 10
    Electronic Resource
    Electronic Resource
    A growth factor from spinal cord (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 100 (1979), S. 273-277 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Mitogenic activity is present at a variety of sites in the central nervous system. A growth factor was purified from neonatal bovine spinal cord. It has a pI of 9.5-9.8 and a molecular weight of about 11,000 daltons. Spinal cord growth factor is a basic polypeptide that is inactivated by extremely acid or basic conditions. Its mobility on SDS polyacrylamide gels suggests that this factor is different from pituitary FGF and brain FGF-1.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041000208
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