ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Life and Medical Sciences  (14)
  • Computational Chemistry and Molecular Modeling  (8)
  • Wiley-Blackwell  (22)
  • 1985-1989  (22)
  • 1
    Electronic Resource
    Electronic Resource
    Cytogenetic evaluation of human endothelial cell cultures (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 132 (1987), S. 453-462 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Cytogenetic evaluation of serially subcultivated human endothelial cells revealed significant differences between cultures derived from fetal umbilical cords and cultures derived from various vessel sites in adults. A rapid increase in the prevalence of polyploid cells, to levels of 100% in many cases, was detected in human umbilical vein endothelial cell cultures but not in endothelial cell cultures from adult vessels. Because the development of polyploidy has been viewed as one signpost of in vitro senescence, it may be that these in vitro observations of high levels of polyploidy are a reflection of the fact that umbilical tissue is at the end of its in vivo developmental lifespan when studied. Consistent karyotypic alterations also were observed in two clones from adult human abdominal aorta, even though these cultures exhibited low percentages of polyploid cells. Cultures of one clone exhibited a trisomy of chromosome 11, on which there are at least three onc gene loci, and a deletion of chromosome 13 through band q14. A loss of band 13q14 is a prezygotic chromosomal lesion known to predispose to retinoblastoma. In the other clone, two cell populations were observed, and each displayed a chromosomal abnormality A trisomy of the long arm of chromosome 2 was noted in one cell population via a marker chromosome involving 2 and 14. The other cell population exhibited an abnormality of chromosome 2. Neither of these karyotypic alterations was detected in the parent culture from which the clones were derived. The results reported in this study have both practical and theoretical implications. The high incidence of polyploidy in serially cultivated umbilical cultures as well as the occurrence of chromosomal changes in umbilical and aortic cultures testify to the need for cytogenetic monitoring of cell cultures even though they are derived from presumably normal tissue. Cytogenetic changes in the endothelium may be important in atherogenesis and other pathologic states. The conversion of diploid endothelial cells into polyploid endothelial cells may provide a convenient model cell system for studying mechanisms of the development of polyploidy in cells and their relationship to in vitro senscence.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041320307
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The role of erythropoietin in the production of principal erythrocyte proteins other than hemoglobin during terminal erythroid differentiation (1986)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 126 (1986), S. 259-265 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Erythropoietin (EP) controls the terminal phase of differentiation in which proerythroblasts and their precursors, the colony forming units-erythroid (CFU-e), develop into erythrocytes. Biochemical studies of this hormone-directed terminal differentiation have been hindered by the lack of a homogeneous population of erythroid cells at the developmental stages of CFU-e and proerythroblasts that will synchronously differentiate in response to EP. Such a population of cells can be prepared from the spleens of mice with the acute erythroblastosis resulting from infection with anemia-inducing Friend virus (FVA). Using these FVA-infected erythroid cells, which were induced to differentiate with EP, four proteins other than hemoglobin that have key functions in mature erythrocytes were monitored during the 48-hour period of terminal differentiation. Synthesis of spectrin and membrane band 3 proteins were determined by immunoprecipitation and SDS-polyacrylamide gel electrophoresis; accumulation of the cytoskeletal protein band 4.1 was monitored by immunoblotting; carbonic anhydrase activity was measured electro-metrically. Band 3 synthesis and band 4.1 accumulation could be detected only after exposure of the cells to EP. Spectrin synthesis was ongoing prior to culture with EP, but it did increase after exposure to the hormone. Carbonic anhydrase-specific activity changed very little throughout the terminal differentiation process. These results reveal at least three patterns of production of principal erythrocyte proteins during EP-mediated terminal differentiation of FVA-infected erythroid cells. Depending on the specific protein examined, de novo synthesis can be induced by EP, an ongoing production can be enhanced by EP, or the production of a protein can be completed at a developmental stage prior to EP-mediated differentiation in these cells.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041260216
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Regulation of angiotensin I-converting enzyme activity in serially cultivated bovine endothelial cells (1985)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 122 (1985), S. 30-38 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Angiotensin I-converting enzyme (ACE) activity was measured in lysates of cloned and uncloned cultures of bovine fetal aortic endothelial cells. The expression of ACE activity in these cells was complex, and influenced by subcultivation, cell density, serum, cumulative population doublings, and clonal heterogeneity. The ACE specific activity at any point in the in vitro lifespan was determined, at least in part, by interaction of these culture variables. After subcultivation to subconfluent densities, cellular ACE specific activity decreased markedly and did not reach detectable levels until cells attained confluent densities. The use of different suppliers' lots of serum in the growth medium resulted in different cellular ACE specific activities. The ACE specific activity decreased as cultures were serially subcultivated, but remained detectable throughout the lifespan, suggesting a linkage between the proliferative history of an endothelial cell and its remaining capacity to express ACE. Increased ACE activity was observed when cells at the end of their lifespan were cultured at high densities. Cloned strains behaved similarly to the uncloned parent culture, except that they exhibited a wide range of ACE specific activities.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041220106
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Release of angiotensin I-converting enzyme by endothelial cells in vitro (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 131 (1987), S. 1-5 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Bovine fetal aortic endothelial cells cultured in serum-containing medium accumulate angiotensin I-converting enzyme (ACE) activity and also release it into the culture medium. Following subcultivation of a confluent culture using trypsin-EDTA, cellular ACE activity falls 50% within 8 h, but no ACE activity is detected in the medium, suggesting intracellular loss of the enzyme activity. ACE activity reappears in both the cell lysate and culture medium after the culture becomes confluent. The rate of accumulation of ACE activity released into the medium is always greater than that for cellular activity. For example, 21 days following subcultivation 80-85% of the total culture activity is detected in the medium. Both cellular and medium-associated ACE decrease proportionately as the culture progresses through its in vitro lifespan.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041310102
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Stabilization by heparin of acidic fibroblast growth factor mitogenicity for human endothelial cells in vitro (1989)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 140 (1989), S. 439-448 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The effects of heparin and other glycosaminoglycans (GAGs) on the mitogenicity and stability of acidic fibroblast growth factor (aFGF) were studied. The mitogenic activity of aFGF was assayed utilizing cultured adult human endothelial cells (AHECs) isolated from iliac arteries and veins as target cells. In most experiments, aFGF purified from bovine brain was employed; in some experiments recombinant bovine aFGF was used and qualitatively similar results were obtained. In the presence of heparin, bovine aFGF at doses between 0.5 and 1.0 ng/ml (30-60 pM) elicited half the maximum AHEC growth over a 4-day period depending on the cell line tested; in the absence of heparin, significant growth was not observed at aFGF concentrations less than 10-20 ng/ml. This effect of heparin was dose-dependent over the range 0.1-10 μg/ml (half-maximum dose, 2 μg/ml). The mitogenic activity of bovine aFGF for AHECs decreased by 50% after preincubation in culture medium without cells at 37°C for 2 ½ to 3 hours. In contrast, the mitogenic activity of bovine aFGF preincubated in the presence of heparin-containing culture medium without cells was dramatically stabilized (half-life 24-29 hours). These effects also were observed in serum-free medium. Several GAGs structurally related to heparin such as chondroitin-4-sulfate, chondroitin-6-sulfate, dermatan sulfate, and hyaluronic acid neither potentiated nor stabilized aFGF mitogenic activity. However, heparan sulfate from bovine lung was found to be nearly as active as heparin in both these effects. These data suggest that the binding and stabilization of mitogens by extracellular and tissue-associated heparan sulfates might play important roles in the regulation of AHEC growth.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041400306
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Growth-related changes of oxygen consumption rates of tumor cells grown in vitro and in vivo (1989)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 138 (1989), S. 183-191 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Growth-related changes of oxygen consumption rates of tumor cells, grown in vitro or in vivo, were investigated. For in vitro investigations, L929 and DS-carcinosarcoma cells were cultured in artificial media. For in vivo studies, DS-carcinosarcoma cells were implanted into the abdominal cavity of Sprague-Dawley rats (ascites tumor, containing malignant cells, leukocytes, lymphocytes, and macrophages). Oxygen uptake was measured photometrically. Parameters of the extracellular medium judged to possibly influence the respiratory activity of tumor cells were monitored at different growth stages (glucose, lactate, and amino acid levels, oxygen and carbon dioxide partial pressures, and pH values). The results obtained clearly show that the oxygen uptake of tumor cells grown in vitro decreased as quiescence developed. In contrast, the respiratory activity of in vivo DS-carcinosarcoma ascites cells increased as tumor growth reached plateau phase. The differences observed cannot be attributed solely to changes of the environmental conditions monitored. It is likely that an increased respiration rate of activated host cells might profoundly contribute to the elevation of the respiratory capacity of DS-carcinosarcoma ascites tumors grown in vivo. These data provide evidence that solid tumors in vivo can increase their O2 uptake at an enhanced O2 availability not only due to an enlarged tumor volume with adequate O2 supply but also due to an elevation of the respiratory activity of different cell populations within a tumor.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041380124
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    A mammary-derived growth inhibitor (MDGI) related 70 kDa antigen identified in nuclei of mammary epithelial cells (1989)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 138 (1989), S. 415-423 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The aim of the present study was to investigate the expression of the mammary derived growth inhibitor (MDGI) and the subcellular localization of MDGI related antigens in bovine mammary glands. Cell-free translation of poly (A+) = RNA, immunoprecipitation with rabbit anti-MDGI-antibodies, and estimation of the relative contents of MDGI by a radioimmunoassay in mammary tissue of different functional statess revealed that the 13 kDa MDGI was dramatically increased in terminally differentiated mammary tissue compared with the proliferating tissue from pregnant animals. To address the question of tissue localizationl, polyclonal anti-MDGI antibodies and antibodies directed aganist a sythetic peptide corresponding ot residues 69 to 78 of MDGI were used. Western blotting of tissue fractions revealed the cytosolic and microsomal localization of MDGI. Additionally, both types of antibodies a 70-kDa antigeninthe unclear fractionof differentiated mammary glands. Salt extraction and DNase I digestion of isolated unclei, as well as chromatin purification, indicated an association of the 70-kDa antigen with the chromatin. By means of the immunogold technique, MDGI-related antigens were localized within euchromatic unclear regions of epithelial cells in the intact differentiated mammary gland. The immunostaining was markedly diminished in the proliferating tissue. This finding raises the possibility that MDGI and the 70-kDa antigen influence cell proliferation by acting on geneexpression within the unclei of mammary glands.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041380225
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Coupling of antagonistic signalling pathways in modulation of neutrophil function (1989)
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 40 (1989), S. 287-294 
    Details
    ISSN: 0730-2312
    Keywords: superoxide ; neutrophils ; cell response modulation ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Modulation of neutrophil activation by catecholamines reflects a fine-tuning by coupling inhibitory and stimulatory receptor pathways. The catecholamine isoproterenol (ISO) binds to beta-adrenergic cell surface receptors and thereby inhibits cell responses such as O2- production stimulated by formyl peptides. However, ISO did not inhibit O2- generation activated by 1 μM ionophore A23187, the protein kinase C activators phorbol ester (PMA, 100 ng/ml) and oleoylacetylglycerol (OAG, 50 μM), and the G-protein activator NaF (40 mM). Furthermore, the overall kinetics of oxidant production in the presence of ISO were unchanged when cells were stimulated with PMA, OAG, A23187, and NaF. These results would imply that neither intracellular calcium, the activation of protein kinase C, nor the activation of G-protein are the primary target of the inhibitory pathway. Accordingly, pertussis toxin did not block PMA or NaF-stimulated superoxide generation. In contrast, formyl peptide-dependent GTPase activity is inhibited by ISO in sonicated cell preparations. Since ISO increases the cAMP concentration in the cell, the possibility is raised that a cAMP-dependent kinase inhibits signal transduction in part by blocking the interaction of this receptor with its G-protein.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcb.240400305
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Sponge aggregation factor: In situ localization by fluorescent monoclonal antibody techniques (1986)
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 31 (1986), S. 251-258 
    Details
    ISSN: 0730-2312
    Keywords: aggregation factor ; monoclonal antibodies ; reaggregation ; cell recognition ; Geodia cydonium ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: The aggregation factor (AF) from sponges mediates a heterophilic interaction of homologous cells. Applying electron microscopical means, we succeeded only very rarely in identifying the 90 S AF particle in tissue sections from Geodia cydonium. By means of a fluorescent antibody technique, we have now localized the cell binding domain of the AF in situ. Previous studies in this laboratory have led to the identification of the 47-kDa cell binding protein of the AF, using the monoclonal antibody (mab) 5D2-D11 [Gramzow M, Bachmann M, Zahn RK, Uhlenbruck G, Dorn A, Müller WEG, J Cell Biol, 102:1344-1349, 1986]. This mab and mab 7D5, directed against a 92-kDa protein in the AF complex, were chosen for the fluorescent studies. By using mab 5D2-D11, the plasma membranes of cells from different regions in the sponge could be brightly stained. However, mab 7D5 reacted only very weakly with the sponge surfaces. By applying the immuno-blotting technique it was furthermore demonstrated that the cell binding protein is present both in the associated form with AF complex and in a free state. Moreover, it was established that the 47-kDa binding protein is not present in (1) homologous glycoconjugates, (2) lectin, or (3) collagen; these components are known to be involved in cell-matrix interaction.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcb.240310402
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    On the identification numbers for chemical structures (1986)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 30 (1986), S. 173-183 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several identification (ID) numbers for chemical structures (connectivity ID number, prime ID number, weighted ID number) are analyzed and tested until a counterexample (a pair of structures with the same ID number) is found. The analysis is carried out for acyclic structures with up to 20 atoms, trees with up to 20 points, benzenoid graphs and polyhexes with up to 10 hexagons, and all connected graphs with up to 6 points.Although all the (chemical) ID numbers studied are highly selective for many families of (molecular) graphs, none of them are unique: in all three cases the counterexamples are found. However, the greatest discriminative power is shown by the weighted ID number.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560300718
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...