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
  • 1
    Electronic Resource
    Electronic Resource
    Three-dimensional imaging and image analysis of hippocampal neurons: Confocal and digitally enhanced wide field microscopy (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Microscopy Research and Technique 29 (1994), S. 269-278 
    Details
    ISSN: 1059-910X
    Keywords: Three-dimensional light microscopy ; Brain slices ; Neurobiology ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: The microscopy of biological specimens has traditionally been a two-dimensional imaging method for analyzing what are in reality three-dimensional (3-D) objects. This has been a major limitation of the application of one of science's most widely used tools. Nowhere has this limitation been more acute than in neurobiology, which is dominated by the necessity of understanding both large-and small-scale 3-D anatomy. Fortunately, recent advances in optical instrumentation and computational methods have provided the means for retrieving the third dimension, making full 3-D microscopic imaging possible. Optical designs have concentrated on the confocal imaging mode while computational methods have made 3-D imaging possible with wide field microscopes using deconvolution methods. This work presents a brief review of these methods, especially as applied to neurobiology, and data using both approaches. Specimens several hundred micrometers thick can be sampled allowing essentially intact neurons to be imaged. These neurons Image analysis in 3-D is as important as visualization in 3-D. Automated methods of cell counting and analysis by nuclear detection as well as tracing of individual neurons are presented. © 1994 Wiley-Liss, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jemt.1070290403
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Metabolic correction of fucosidosis fibroblasts by human α-L-fucosidaseThis work was supported by research grants from the National Institutes of Health (GM19433) and from the National Foundation-March of Dimes (1-535). (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 98 (1979), S. 225-235 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Human α-L-fucosidase, purified from placenta, was taken up from the culture medium by skin fibroblasts from patients with fucosidosis (α-L-fucosidase deficiency). The rate of uptake was low (uptake coefficient = 6 × 10-4 ml.mg-1.h-1). Intracellular α-L-fucosidase activity was directly proportional to enzyme in the medium up to an activity of at least 40 nmoles/min/ml. No evidence for saturation of specific cell-surface receptors was seen. However, uptake was reduced by 75% by 1 mM mannose-6-phosphate and by 50% by 1 mM glucose-6-phosphate, suggesting that uptake may be mediated by a receptor recognising a phosphorylated sugar or an analagous compound. Enzyme taken up by the cells was most active in subcellular fractions enriched with lysosomes and had an isozyme pattern, by isoelectric focusing, identical to that of the original enzyme preparation.Fucosidosis fibroblasts were shown to accumulate low molecular-weight, fucose-containing compounds to a level several times greater than control cells. This stored material was eluted from Sephadex G-25 as an asymmetrical peak with an elution volume of approximately twice the void volume of the column. Addition of placental α-L-fucosidase to the culture medium of fucosidosis fibroblasts prevented excessive accumulation of fucose-containing material and accelerated the breakdown of material accumulated prior to enzyme uptake.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1040980124
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Characterization of a simian virus 40-transformed human podocyte cell line producing type IV collagen and exhibiting polarized response to atrial natriuretic peptide (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 152 (1992), S. 599-616 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Biology of glomerular visceral epithelial cells (“podocytes”) and their role in inflammatory process remain obscure, partly because of the lack of well-differentiated podocyte cultures. We have established a human cell line by transfecting with a replication-defective SV40 plasmid (pSVHB1), a primary culture of podocytes derived from an enriched preparation of unencapsulated glomeruli free of tubule and Bowman's capsule contaminants. Podocyte specificity of the primary culture was assessed by a dual immunomorphological and functional approach. The resulting cell line (HGVEC. SV1) was cloned and the clonal cells were adapted to hormonally defined medium supplemented with only 2% newborn bovine serum. Clone A4 has been exhibiting over 35 passages, a combination of markers unique to podocytes, including expression of vimentin, podocalyxin, ectoenzymes (CALLA antigen and mRNA), heparan-sulfate proteoglycans (molecular mass of core protein = 75 kDa), and production of type IV collagen (α1 and α5 chains) established by immunoprecipitation and Northern blot analysis. Cytokeratin was detected in rare cellular foci and the search of Von Willebrand factor was negative. This clonal cell line has been used to demonstrate: (1) that human podocytes are highly sensitive to atrial natriuretic peptide (ANP) which induced a dose-dependent increase in cGMP production (x20 at 0.5 μM ANP), and (2) that secretion of ANP-stimulated cGMP is dramatically polarized as 93% of extracellular cGMP were released in the apical medium when filter-grown HGVEC. SV1A4 cells were stimulated at their basal pole. © 1992 Wiley-Liss, Inc.
    Additional Material: 17 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041520320
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Inhibition of cellular proliferation and modulation of insulin-like growth factor binding proteins by retinoids in a bovine mammary epithelial cell line (1996)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 167 (1996), S. 488-499 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Retinoids are potent inhibitors of growth and tumor progression in many mammary carcinoma cell lines, though regulation of growth in nontumorigenic mammary epithelial cells by retinoids is less clear. Here, we have characterized the inhibition of MAC-T (a nontransformed bovine mammary epithelial cell line) cellular proliferation by retinoids and their role in regulating insulin-like growth factor binding proteins (IGFBPs). Retinoic acid (RA) (100 nM) was a potent inhibitor of MAC-T cell proliferation. Retinol was 10-100 times less effective. Neither retinoid could completely arrest growth at noncytotoxic concentrations. Retinoic acid inhibited cellular proliferation by 1 h (P 〈 .05), but inhibition was fivefold greater by 24 h (P 〈 .01). This second stage of growth inhibition (after 12 h) was dependent upon protein synthesis. However, RA-induced inhibition of cellular proliferation did not persist, with thymidine incorporation increasing toward control levels by 4 days in culture. Retinoic acid was less effective in inhibiting thymidine incorporation when cells were stimulated with insulin, des(1-3) IGF-I, or Long(R3) IGF-I when compared to cells stimulated with native IGF-I or serum. Inhibition of proliferation by RA was associated with increased levels of IGFBP-2 in conditioned media and in plasma membrane preparations. Treatment with insulin or des(1-3) IGF-I resulted in the appearance of IGFBP-3 in conditioned media and on the cell surface. However, RA significantly reduced IGFBP-3 levels in conditioned media and eliminated IGFBP-3 associated with the plasma membrane. Thus, RA is a potent but transient inhibitor of bovine mammary epithelial cell proliferation, and this growth inhibition is correlated with increased IGFBP-2 accumulation and inhibition of IGF-I stimulated IGFBP-3 protein secretion. © 1996 Wiley-Liss, Inc.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 5
    Electronic Resource
    Electronic Resource
    Modulation of cardiac myocyte phenotype in vitro by the composition and orientation of the extracellular matrix (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 161 (1994), S. 89-105 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Cellular phenotype is the result of a dynamic interaction between a cell's intrinsic genetic program and the morphogenetic signals that serve to modulate the extent to which that program is expressed. In the present study we have examined how morphogenetic information might be stored in the extracellular matrix (ECM) and communicated to the neonatal heart cell (NHC) by the cardiac α1β1 integrin molecule. A thin film of type I collagen (T1C) was prepared with a defined orientation. This was achieved by applying T1C to the peripheral edge of a 100 mm culture dish. The T1C was then drawn across the surface of the dish in a continuous stroke with a sterile cell scraper and allowed to polymerize. When NHCs were cultured on this substrate, they spread, as a population, along a common axis in parallel with the gel lattice and expressed an in vivo-like phenotype. Individual NHCs displayed an elongated, rod-like shape and disclosed parallel arrays of myofibrils. These phenotypic characteristics were maintained for at least 4 weeks in primary culture. The evolution of this tissue-like organizational pattern was dependant upon specific interactions between the NHCs and the collagen-based matrix that were mediated by the cardiac α1β1 integrin complex. This conclusion was supported by a variety of expermental results. Altering the tertiary structure of the matrix or blocking the extracellular domains of either the cardiac α1, or β1 integrin chain inhibited the expression of the tissue-like pattern of organization. Neither cell-to-cell contact or contractile function were necessary to induce the formation of the rod-like cell shape. However, beating activity was necessary for the assembly of a well-differentiated myofibrillar apparatus. These data suggest that the cardiac α1 β1 integrin complex serves to detect and transduce phenotypic information stored within the tertiary structure of the surrounding matrix. © 1994 Wiley-Liss, Inc.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041610112
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Characterization of transforming growth factor-β growth regulatory effects and receptors on bovine mammary cells (1995)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 165 (1995), S. 339-348 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Transforming growth factor-β (TGF-β) has been shown to inhibit mammary morphogenesis, growth, and differentiation in murine studies. We have characterized TGF-β receptors and their autoregulation, and the growth response to TGF-β1 and TGF-β2 in cultured bovine mammary epithelium (MAC-T) and fibroblasts. Affinity labelling studies revealed that fibroblast and epithelial cells contained type I, II, and III (betaglycan) receptors, with the type III receptor being the predominant binding component. On both fibroblasts and epithelial cells, TGF-β1 and TGF-β2 had equal binding affinities for the type I and II receptors, but TGF-β2 had a higher affinity for the type III receptor. Also, preincubation of MAC-T cells with 50 pM TGF-β1 or TGF-β2 markedly downregulated TGF-β receptors. Proliferative response was measured using both total DNA and 3H-thymidine incorporation. Both TGF-β isoforms were effective in inhibiting proliferation of MAC-T cells and fibroblasts. Inhibition of proliferation was not altered following immortalization of fibroblasts with SV-40 Large-T-antigen (LT), even when the cells acquired a transformed phenotype. Inhibition of proliferation was not a result of cytotoxicity, as TGF-β at concentrations 1,000-fold higher than ED50 levels did not increase cell death. Moreover, the inhibition was reversible as shown by return of cellular proliferation to control levels following TGF-β removal. Although growth inhibition was not transient as culture of MAC-T cells in TGF-β resulted in sustained inhibition of proliferation for at least 144 h. © 1995 Wiley-Liss, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041650215
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Leukemia inhibitory factor and interleukin-11 promote maturation of murine and human megakaryocytes in vitro (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 153 (1992), S. 305-312 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The growth-promoting activities of optimally stimulating concentrations of leukemia inhibitory factor (LIF) and interleukin-11 (IL-11), a stromal cell-derived cytokine, on megakaryocytes in liquid marrow cultures were compared to interleukin-6 (IL-6), a known megakaryocytic maturation factor. Maximally stimulating concentrations of LIF (25 ng/ml), IL-11 (10 ng/ml), or IL-6 alone (10 ng/ml) promoted an 81, 157, and 153% increase, respectively, in acetylcholinesterase (AchE) activity in murine serum-free cultures compared with controls (n = 5). In combination with 25 U/ml murine interleukin-3 (IL-3), LIF, IL-6, and IL-11 showed increases, respectively, of 35%, 49%, and 174% in AchE activity compared with IL-3 alone (n = 4). Flow cytometric analysis of 4-day-old cultures showed that LIF alone had minimal effect on megakaryocytic ploidy, whereas IL-11 and IL-6 alone markedly augmented high ploidy cells. Enumeration of cells stained for AchE showed that IL-11 increased the numbers of Mks in comparison to LIF, IL-6 or controls by up to 59%. Moreover, a twofold increment in Mk number was noted when IL-11 was used in combination with IL-3 (compared with either IL-3 alone of IL-3 + IL-6). Flow cytometric ploidy analysis of 8-day-old human liquid marrow cultures showed that either LIF, IL-11, or IL-6 alone markedly augmented the percentage of 32N cells compared with cultures containing only human IL-3. The data suggest that LIF and IL-11 promote murine and human Mk maturation in vitro, although the effect of IL-11 exceeds that of LIF in mice. Despite the comparable influence of IL-11 and IL-6 on Mk ploidy, IL-11 has the additional characteristic of enhancing the number of Mks, particularly in combination with IL-3. © 1992 Wiley-Liss, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041530210
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Influence of proteins in rat cauda epididymidal lumen fluid on cauda sperm motility (1987)
    New York, NY : Wiley-Blackwell
    Gamete Research 18 (1987), S. 267-278 
    Details
    ISSN: 0148-7280
    Keywords: micro puncture ; fractionation ; viscosity ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Rat cauda epididymidal spermatozoa are kept quiescent in the cauda lumen by a protein fraction termed “immobilin”, but it has not been shown whether or not this activity is unique to the immobilin fraction. Cauda fluid was subjected to gel filtration chromatography and the eluents contributing to three peaks of absorbance at A280 were pooled, lyophylized, and reconstituted at equivalent concentrations. Their relative viscoelasticity and their effects on sperm motility were determined. Peak 1 (P1), containing proteins 〉 400 kd, retained the greatest sperm-immobilizing activity, but P2 and P3 also had sperm-immobilizing activity related to their viscoelasticity. P1 and an immobilin fraction obtained by ultracentrifugation of rat cauda fluid were generally similar in their sperm-immobilizing activity, viscoelasticity index, electrophoretic patterns, and binding characteristics to Concanavalin A; thus, the sperm-immobilizing factor obtained by gel filtration chromatography and the immobilin fraction obtained by centrifugation are believed to be the same products. Further, it was shown that intraluminal testicular fluids did not inhibit cauda sperm motility even at epididymal-like protein concentrations; thus, it is believed that the sperm-immobilizing factor(s) is of epididymal, not testicular, origin.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120180307
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Network formation during vinyl polymerization via inorganic particles (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 811-818 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Methyl methacrylate containing a small amount of 4-methacryloxyethyl trimellitate anhydride (1.0-1.5 wt %) yielded an insoluble network when polymerized in the presence of various inorganic powders, such as lithium aluminum silicate. This unexpected result was obtained for polymerization initiated either by exposure to γ-rays or by heating with azobisisobutyronitrile. In contrast, polymerization in the absence of inorganic powder gave the expected soluble products. Therefore, it is concluded that the inorganic particles play a role in network formation. In order to account for network formation even in a supernatant layer of clear monomer, i.e., above the centrifuged sedimentation volume of the powder, it is suggested that the monomer reacts on the surface of particles to form a diffusive crosslinking agent.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.170210316
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    The emulsion copolymerization of styrene and sodium styrene sulfonate (1985)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 535-548 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The emulsion copolymerization of styrene and sodium styrene sulfonate has been shown to be a feasible preparative route to ionomeric sulfonated polystyrene. The properties of these copolymers are reported elsewhere. The copolymerization rate was found to be dramatically enhanced when compared to that for the emulsion copolymerization of styrene under identical conditions. This copolymerization was studied in detail and two mechanisms were proposed to account for these rate differences. An increase in the number of polymerizing particles in the copolymerization with consequent rate enhancement was substantiated by electron microscopy. However, the data indicate that the rate differences cannot be fully accounted for by this effect. In addition, a gel effect is proposed as a second contributor to the enhanced rate. This gel effect is believed to result from the intermolecular association of the incorporated metal sulfonate units in the growing polymer particles. When a third monomer that plasticizes the ionic interactions is used the polymerization rate decreases. This supports the gel effect hypothesis.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1985.170230227
    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...