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  • 1
    Electronic Resource
    Electronic Resource
    Calmodulin intracelluar concentration and cAMP-dependent protein kinase activity in human sperm samples in relation to sperm motphlogy and motlity (1983)
    New York, NY : Wiley-Blackwell
    Gamete Research 8 (1983), S. 171-182 
    Details
    ISSN: 0148-7280
    Keywords: calmodulin ; cAMP-dependent protein kinases ; sperm structural anomalies ; cell motility ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Calmodulin concentration and cAMP-dependent protein kinase activity have been determined in human sperm samples. No significant differences have been noticed in the motility index of two groups of sperm samples differing in their intracellular concentration of calmodulin. It was however found that a low intracellular clamodulin concentration is frequently associated with particular anomalies of the head and tail region. In contrast, a positive correlation has been demonstrated between the motility index and the whole extractable cAMP-dependent protein activity of the different sperm samples. In suspension s, When the cAMP-dependent protein kinase activity was measured on intact sperm suspensions, a positive correlation between the activity and the motility index was also found.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120080206
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  • 2
    Electronic Resource
    Electronic Resource
    Okadaic acid and p13suc1 modulate the reinitiation of meiosis in mouse oocytes (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 33 (1992), S. 287-296 
    Details
    ISSN: 1040-452X
    Keywords: Cell cycle regulation ; Spindle formation ; M phase-promoting factor ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Short-term exposure to okadaic acid (OA), a specific inhibitor of protein phosphatases 1 and 2A, induced resumpton of meiosis, including metaphase spindle formation, in mouse oocytes treated with a phosphodiesterase inhibitor, while long incubations with OA arrested oocyte maturation at a step prior to spindle formation. To explore the basis for this difference, the overall patterns of protein synthesis and phosphorylation and the production of tissue-type plasminogen activator (tPA), the synthesis of which is induced after germinal vesicle breakdown (GVBD), were analyzed under various OA treatments. Short-term exposure to OA led to tPA production and did not greatly affect the maturation-associated changes in protein phosphorylation. By contrast, a long application of OA did not result in tPA production and induced more marked changes in protein phosphorylation.Microinjection into prophase oocytes of the the product of the fission yeast gene p13suc1, known to inhibit p34cdc2 kinase activation and/or activity, prevented meiotic reinitiation. This effect was overcome by microinjection of OA, at concentrations higher than those required for induction of maturation in the absence of p13suc1. These observations suggest that inhibition of phosphatase 1 or 2A or both triggers meiotic resumption by acting at the same site or at a site proximal to the p13suc1-sensitive step of cdc2 kinase activation. © 1992 Wiley-Liss, Inc.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1080330309
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  • 3
    Electronic Resource
    Electronic Resource
    Further characterization of four lipocortins from human peripheral blood mononuclear cells (1989)
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 40 (1989), S. 361-370 
    Details
    ISSN: 0730-2312
    Keywords: phospholipase A2 ; lipocortins ; phosphorylations ; actin-binding ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Four calcium and phospholipid binding proteins purified from mononuclear cells were characterized for PKC and EGF phosphorylation, actin binding capacity, and partial tissue distribution. Those named 35K, 32K, and 73K are equivalent, respectively, to lipocortin III, endonexin II and the 67 kDa calelectrin; 36K is a fragment of 73K. After purification, 35K and 73K were phosphorylated by protein kinase C in vitro but 36K nor 32K were not. None were phosphorylated by the epidermal growth factor receptor kinase in vitro; 73K bound F-actin in a calcium-dependent manner, whereas 35K, 36K, and 32K did not. Using Western blotting analysis, 32K and 73K were detected in high amounts in human lymphocytes, monocytes, liver, and placenta and in rat adrenal medulla; but 32K was not detected in polymorphonuclear cells, and 36K and 35K were detected in high amounts only, respectively, in human blood lymphocytes and polymorphonuclear cells. Thus, 32K and 73K appear to have a wide tissue distribution, whereas 35K has a much more restricted distribution.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcb.240400312
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  • 4
    Electronic Resource
    Electronic Resource
    Structure and mass analysis of 12S and 19S dynein obtained from bull sperm flagella (1987)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 8 (1987), S. 368-374 
    Details
    ISSN: 0886-1544
    Keywords: STEM ; polypeptide composition ; ciliary motility ; dynein molecule ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The Brookhaven scanning transmission electron microscpe (STEM) was used to elucidate the structures and masses of 12S and 19S dynein extracted from bull sperm flagella. The 12S particle was a single globular particle with an average mass of 311 ± 10 kdaltons. The 19S dynein particles consisted of two globular heads joined to a common base. The average mass of the 19S particle was 1.6 ± 0.04 × 106 daltons. Thus, with the exception of the larger mass, the bull sperm 19S dynein molecule resembles the two-headed 21S dynein obtained from sea urchin sperm flagella and the 18S dynein obtained from Chlamydomonas with the possibility of a third head giving rise to the 12S particle. The structure, mass and polypeptide composition of bull sperm flagella dynein is compared with outer arm dyneins previously obtained from Chlamydomonas, Tetrahymena, and sea urchin sperm flagella.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970080409
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  • 5
    Electronic Resource
    Electronic Resource
    Protease inhibitor and substrates block motility and microtubule sliding of sea urchin and carp spermatozoa (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 518-527 
    Details
    ISSN: 0886-1544
    Keywords: 9 + 2 flagellar beating ; aprotinin ; axonemes ; protease inhibitor ; sperm motility ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The effects of protease substrates and inhibitor, which have been previously shown to inhibit mammalian sperm motility (de Lamirande, E., and Gagnon, C. [1986] J. Cell Biol. 102:1378-1383), were investigated using reactivated sea urchin and carp spermatozoa as models of “9 + 2” flagella. Aprotinin in the 2 to 20 μM range interfered with sperm motility by reducing both the beat frequency and the percentage of motile spermatozoa. These inhibitory effects of aprotinin were reversible either by dilution or by the addition of high concentrations of MgATP to the incubation medium. Protease substrates with a lys-ester bond, such as N-α-benzyloxycarbonyl-lys thiobenzyl ester (BLT), also affected motility, but in the 0.1 to 0.5 mM range. As with aprotinin, both the flagellar beat frequency and the percentage of motile spermatozoa were partially and completely decreased, respectively. Analysis of the beat frequencies as a function of MgATP concentration in the presence and absence of 6 μM aprotinin indicated that this protease inhibitor affects sperm motility by decreasing the maximal flagellar beat frequency rather than by altering the axoneme's apparent Km for MgATP. Furthermore, aprotinin concentrations that blocked flagellar reactivation completely inhibited the sliding of microtubules from trypsinized axonemes. Basic proteins or polypeptides of pI close to that of aprotinin (10.3) were also potent inhibitors of the reactivation of motility. However, the characteristics of their inhibition of flagellar beat frequencies and reversibility of their effects suggested that they might be acting on sites different from those sensitive to aprotinin. The inhibitory effects of protease inhibitor and substrates, as well as results of experiments showing the absolute requirement of an intact ester bond for the inhibitory action of protease substrates, suggest that the involvement of a protease in the reactivation of 9 + 2 flagellar beating might be considered as a possible mechanism to explain aprotinin and BLT actions.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970100408
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  • 6
    Electronic Resource
    Electronic Resource
    Prelimlnary report on the ultrastructural organization of the contractile appendix of Tontonia appendiculariformis (ciliophora oligotrichina) (1986)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 6 (1986), S. 217-224 
    Details
    ISSN: 0886-1544
    Keywords: contractile system ; microfilaments ; microtubules ; endoplasmic reticulum ; ciliophora ; oligotrichina ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Tontonia appendiculariformis is a marine planktonic ciliate with a long tail. The tail can contract rapidly, becoming transformed into an oval mass one-twentieth of its original length. The highly complex ulrastructure of the tail is described here in detail. A large part of the volume of the tail contains numerous more or less parallel membranous tubes. The membrane of the tubes has numerous invaginations and is probably derived from the smooth endoplasmic reticulum. This tubular material forms a continuous layer around the tail, interrupted in only one region, which contains cilia. Associated with the cilia are basal fibres with a periodically banded appearance. The tubular layer forms several folds separated by hyaloplasm containing many mitochondria. The pellicle of the tail is thrown into numerous pleats. It comprises a perilemma, a plasmalemma, and complex alveoli, but epiplasm and microtubules are absent. The alveoli appear to form septa within the folds of the layer of membranous tubes. In the region where the tail is attached to the body of the ciliate there are conspicuous bundles of microtubules and microfilaments. The membranous tubes and septa appear to be connected to small bundles of microfilaments, which presumably represent the contractile material. However, we consider the membranous tubes as potentially active in producing the change in shape. Although the structure of the tail of Tontonia is unique, there are certain similarities to the stalk of the Tintinnina and also to the motile extension of the dinoflagellate Erythropsidinium.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970060221
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  • 7
    Electronic Resource
    Electronic Resource
    Reversible intracellular ATP changes in intact rat spermatozoa and effects on flagellar sperm movement (1992)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 21 (1992), S. 210-222 
    Details
    ISSN: 0886-1544
    Keywords: bioluminescence ; ATP depletion ; motility ; flagellum ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The initiation of motility and modification of energy metabolism of rat caudal epididymal spermatozoa can be induced by dilution in a saline medium. We have investigated in these cells the relationships between the energy reserve (sperm ATP content measured by bioluminescence) and flagellar movement (high speed videomicrography, 200 frames/sec). A steady state was observed in sperm ATP content, progressive velocity (Vp) and flagellar beat frequence (F) with sperm dilution in a medium with glucose, lactate, pyruvate and acetate substrates after 30 minutes of incubation, without these substrates, changes in metabolic pathways occurred immediately and initially disturbed the relationship between ATP levels and F, suggesting differences in motility initiation when energy is from an endogenous origin via mitochondrial oxidative phosphorylation. This “energy crisis” was reversed by the addition of substrates to the medium.The three-dimensional flagellar movement observed in the presence of substrates quickly became two-dimensional in their absence. The flagellar beat envelope became more splayed, the mean amplitude of lateral head displacement increased and F decreased. The resulting high flagellar beat efficiency can be compared to that observed during hyperactivation which is a physiological event related to a fall in intracellular ATP level. In both media, the displacement of the flagellum in relation to the wave axis varied sinusoidally. The sine period increased with time when the spermatozoa were incubated in the medium without substrates. These results suggest a gradual slowing-down of the velocity of wave formation in the proximal part of the flagellum.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970210305
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  • 8
    Electronic Resource
    Electronic Resource
    Lipopolysaccharides stimulate Na-dependent transport in alveolar cells and protect against oxidant injury (1995)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 163 (1995), S. 328-338 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: We have evaluated the effect of lipopolysaccharides (LPS), endotoxins from gram negative bacteria, on sodium-coupled amino acid and phosphate transport by alveolar epithelial type II cells and on their alteration induced by oxidants. Alveolar type II cells were obtained by enzymatic digestion of rat lung and grown for 24 h prior to incubation with LPS and then exposed or not exposed to H2O2 (2.5 mM; 20 min). LPS (10 μg/ml, 24 h) induced a significant increase in the Na-dependent component of alanine and phosphate uptake while they decreased Na, K-ATPase activity measured by ouabain-sensitive 86Rb influx. We showed that this stimulatory effect i) was independent from macrophage products since it was not mimicked either by supernatant of LPS-treated alveolar macrophages or by pretreatment with tumor necrosis factor and/or interleukin 1 and ii) was dependent on protein synthesis since it was abolished by protein synthesis inhibitors cycloheximide and actinomycin D. Moreover, LPS blunted H2O2-induced decrease of Na-dependent alanine and phosphate uptake. This protective effect of LPS against H2O2 injury i) was independent of macrophage products, ii) was abolished by cycloheximide, and iii) was not associated with either changes in extracellular H2O2 clearance or catalase and glutathione peroxidase activities. We conclude that, in alveolar type II cells, LPS stimulate sodium-coupled transport by a process involving protein synthesis and partially prevent H2O2-induced decrease of Na-coupled transport without discernible change in antioxidant activities. © 1995 Wiley-Liss, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041630214
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  • 9
    Electronic Resource
    Electronic Resource
    Expression of cytochrome P450 in rat pleural mesothelial cells in secondary cultures (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 160 (1994), S. 176-184 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Cultured rat pleural mesothelial cells (RPMC) isolated from male Sprague-Dawley rats have been shown to metabolize polycylic aromatic hydrocarbons to more oxygenated metabolites. This capacity, which is maintained with passages, suggested the presence of monooxygenase enzymes. In order to clarify the enzymatic pathway, we investigated the expression of cytochromes P450 (CYP) in cultured RPMC by Western and Northern blot analyses. Cells were cultured in Ham's F10 medium supplemented with 10% fetal calf serum. The CYP expression was studied from passage 9 to 16 on different cell strains treated for 48 hours with P450 inducers. CYP1A1 apoprotein expression was very low in untreated cells, but was markedly induced after treatment with 1 μM 3-methylcholanthrene or 22 μM β-naphthoflavone. CYP1A1 mRNA was not detected in untreated cells and appeared after 3-methylcholanthrene treatment. CYP2E1 apoprotein was constitutively expressed in cultured RPMC, and markedly increased by 170 mM ethanol, and 0.1 μM or 1 μM dexamethasone treatments. Unexpectedly, whereas the amount CYP2E1 mRNA was not modified by ethanol treatment, dexamethasone has a marked inductive effect on CYP2E1 mRNA level. The CYP expression pattern was found similar in RPMC issued from different rats, and not dependent on passage number. The CYP expression and the detection of NADPH-P450 reductase, and of epoxide hydrolase, ascertained that RPMC contain the overall enzymatic pathway required for the biotransformation and activation of procarcinogen compounds, such as polycyclic aromatic hydrocarbons and nitrosamines. Both expression and regulation properties are maintained in long-term cultures of RPMC. © 1994 Wiley-Liss, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041600120
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  • 10
    Electronic Resource
    Electronic Resource
    Heparin-derived oligosaccharides: Affinity for acidic fibroblast growth factor and effect on its growth-promoting activity for human endothelial cells (1989)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 140 (1989), S. 538-548 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The minimal structural requirements for the interaction of heparin with acidic fibroblast growth factor (aFGF) were investigated. Oligosaccharides (tetra- to decasaccharides) obtained by nitrous acid depolymerisation of standard heparin were separated by affinity chromatography on Sepharose-immobilised aFGF. The shortest fragment retained by the affinity column at 0.2 M NaCl and eluted at 1 M NaCl was a “regular” hexasaccharide, a trimer of the most abundant disaccharide sequence in heparin. More complex octa- and decasaccharides were also retained by the column. The Oligosaccharides eluted by 1 M NaCI from the affinity column (“high-affinity” Oligosaccharides) and those washed from the column at 0.2 M NaCI (“low-affinity” Oligosaccharides) were compared for their capacity to protect aFGF from proteolysis and to potentiate its mitogenic activity. At a low ionic strength, all Oligosaccharides tested, except the “regular” disaccharide, protected aFGF againsttrypsin and collagenase digestion. At higher ionic strength (〉 0.2 M NaCI), only high-affinity Oligosaccharides showed a protective effect. The high-affinity oligosaccharides (hexa- to decasaccharides) potentiated the mitogenic activity of aFGF, as measured by [3H]thymidine incorporation into DNA of human fibroblasts. The effect of the oligosaccharides on human endothelial cell proliferation was more complex: inhibition of proliferation was observed in the presence of serum and low concentrations of aFGF (1-5 ng/ml) and potentiation in the presence of higher concentrations of aFGF. The potentiating effect increased as a function of molecular size of the heparin fragments and, for a given size, as a function of the anionic charge of the oligosaccharide. Our results suggest that inhibition of cell proliferation by heparin may result from interference with an autocrine basic FGF-like activity.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041400320
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