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  • 1
    Electronic Resource
    Electronic Resource
    A polar high molecular mass constituent of bleached kraft mill effluent is toxic to marine organisms (1992)
    s.l. : American Chemical Society
    Environmental science & technology 26 (1992), S. 2413-2420 
    Details
    ISSN: 1520-5851
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/es00036a012
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  • 2
    Electronic Resource
    Electronic Resource
    Toxicity of zinc and bleached kraft mill effluent to larval english sole (Parophrys vetulus) and topsmelt (Atherinops affinis) (1990)
    Springer
    Archives of environmental contamination and toxicology 19 (1990), S. 680-685 
    Details
    ISSN: 1432-0703
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
    Notes: Abstract Toxicity test protocols were developed for larvae of two species of marine fishes of the Pacific coast of the United States. During winter months, larvae were obtained from adult English sole (Parophrys vetulus) spawned in the laboratory. Newly-hatched, nonfeeding larvae were used in 96-hr experiments to determine their acute sensitivity to inorganic and organic toxicants. Exposure to ZnSO4 produced a 96-hr LC50 of 14.5 mg Zn/L. A complex and variable organic effluent (untreated bleached kraft mill effluent; BKME) yielded 96-hr LC50s ranging from 1.2–9.3% BKME. Larvae were obtained from eggs collected from wild and laboratory populations of the spring and summer-spawning topsmelt (Atherinops affinis). Both acute (96-hr) mortality and longer-term (7–14 days) growth responses of topsmelt larvae to BKME were determined. Acute toxicity levels (96-hr LC50s) ranged from 6.2–9.7% BKME. No Observed Effect Levels (NOELs) for 7 and 14 day exposures ranged from 1.0–3.0% BKME.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01183984
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  • 3
    Electronic Resource
    Electronic Resource
    Structure of the cumulus matrix and zona pellucida in the golden hamster: A new view of sperm interaction with oocyte-associated extracellular matrices (1988)
    Springer
    Cell & tissue research 251 (1988), S. 555-564 
    Details
    ISSN: 1432-0878
    Keywords: Cumulus ; Zona pellucida ; Extracellular matrix ; Sperm ; Fertilization ; Golden hamster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Hamster oocyte-cumulus complexes (OCC), with and without sperm, were structurally analyzed by light- and electron microscopy using freeze substitution. This method has yielded a clear picture of the extracellular oocyte investments, the cumulus cell matrix and the zona pellucida. The cumulus matrix has an overall homogeneous fibrillar structure which appears to attach to cumulus cells at their filopodial extensions. The matrix also extends into the outer regions of the zona pellucida. The zona pellucida has a distinct porous configuration throughout its entire structure. During gamete interaction experiments, capacitated hamster sperm with ultrastructurally intact acrosomes were found throughout the matrix. Sperm had dramatic effects on the matrix, resulting in compression and stretching. Sperm found on the zona pellucida had initiated or completed the acrosome reaction. During the initial stages of the acrosome reaction, the matrix was in contact with the sperm. At later stages of the acrosome reaction, there was a complete loss of matrix material in regions near the sperm.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214003
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  • 4
    Electronic Resource
    Electronic Resource
    Gamete interaction in the white sturgeon Acipenser transmontanus: a morphological and physiological review (1985)
    Springer
    Environmental biology of fishes 14 (1985), S. 11-22 
    Details
    ISSN: 1573-5133
    Keywords: Sperm ; Egg ; Fertilization ; Acrosome reaction ; Micropyles ; Chorion ; Jelly ; Protease ; Glycoproteins ; Egg water
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Synopsis Sturgeon gametes differ from those of most fish in that the sperm possess acrosomes that undergo exocytosis and filament formation while the eggs possess numerous micropyles. Acipenser transmontanus eggs are encased by multilayered envelopes that consist of outer adhesive jelly coats and three structured layers interior to the jelly. The glycoprotein jelly layer only becomes adhesive upon exposure to freshwater. The layer interior to the jelly, layer 3, is the other carbohydrate-containing component of the egg envelope. This layer consists of a water-insoluble glycoprotein that, upon freshwater exposure, is hydrolyzed by a trypsinlike protease to yield a water-soluble, lower molecular weight carbohydrate-containing component. This component can be identified in the surrounding medium when unfertilized eggs are incubated in freshwater. This egg water component elicits acrosome reactions only in homologous sperm. The A. transmontanus sperm acrosome reaction is a Ca++ and/or Mg++ dependent event that includes the formation of a 10 μ long fertilization filament. A. transmontanus fertilization can occur at low sperm per egg ratios; however, crossfertilization of A. transmontanus eggs with lake sturgeon, A. fluvescens, sperm results in a very low number of fertilized eggs, even at high sperm per egg ratios. The morphological, physiological, and biochemical phenomenon reviewed in this paper are related to the environment in which they occur. Also, the possible role of the acrosome and the presence of numerous micropyles are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00001572
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  • 5
    Electronic Resource
    Electronic Resource
    Preservation and visualization of the sea urchin embryo blastocoelic extracellular matrix (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Microscopy Research and Technique 22 (1992), S. 11-22 
    Details
    ISSN: 1059-910X
    Keywords: Rapid freezing ; Freeze-substitution fixation ; Confocal microscopy ; Blastocoel ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: Several methods were utilized to visualize the structure and orientation of the blastocoelic extracellular matrix (ECM) in Strongylocentrotus purpuratus embryos at the mesenchyme blastula stage. Rapid freezing in liquid propane cooled to LN2 temperatures followed by freeze substitution was used to preserve the ECM without shrinkage due to dehydration. Scanning, transmission, and light microscopy were employed to elucidate the ECMs' structure. The blastocoelic ECM consisted of parallel fibrillar sheets that were interconnected by finer filaments and oriented along the animal-vegetal axis. The ECM completely filled the blastocoelic cavity as viewed by scanning electron microscopy. The basal lamina could be distinguished from the blastocoelic ECM as a thin coat on the plasma membrane of epithelial cells; the ECM was in contact with this coat. In contrast, the blastocoelic ECM attached directly to the plasma membrane of primary mesenchyme cells (PMC) which did not possess a basal lamina. The blastocoelic ECM was isolated as an intact “bag” and probed in a hydrated state with Con A and alcian blue. Confocal microscopy confirmed that the entire blastocoel was filled with a fibrillar ECM. These approaches offer advantages for future studies of the ECMs of sea urchin embryos and their roles in gastrulation. © 1992 Wiley-Liss, Inc.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jemt.1070220104
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  • 6
    Electronic Resource
    Electronic Resource
    The evolution of hamster sperm motility during capacitation and interaction with the ovum vestments in vitro (1986)
    New York, NY : Wiley-Blackwell
    Gamete Research 14 (1986), S. 333-346 
    Details
    ISSN: 0148-7280
    Keywords: spermatozoon ; motility ; capacitation ; hamster ; fertilization ; acrosome reaction ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Movement characteristics of golden hamster spermatozoa were studied upon collection from the cauda epididymis, during an incubation which capacitates the spermatozoa in vitro, during penetration of the cumulus, and during attachment to and penetration of the zona pellucida. High-speed videomicrography was employed to quantitate flagellar beat frequency and shape. The status of the acrosome was also assessed. During capacitation, hamster spermatozoa become increasingly invigorated before the onset of hyperactivated motility. Within the cumulus, beat frequency and curvature are reduced, apparently in response to the physical resistive properties of the matrix material. These properties appear to vary within the cumulus. Initial attachment to the zona precedes completion of the acrosome reaction, is non-rigid, and is accompanied by increased beat frequency and curvature. Subsequently, the onset of rigid binding to the zona, completion of the acrosome reaction, and increased flagellar beat frequency are very closely associated in time. The latter produces an increase in thrust against the zona. Preliminary results indicate that ensuing zona penetration requires not more than five minutes, is at oblique angles, and is associated with a continuation of vigorous flagellar beating.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120140406
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