TY - JOUR
A1 - Hengelsberg, H.
A1 - Tacke, Reinhold
A1 - Fritsche, K.
A1 - Syldatk, C.
A1 - Wagner, F.
T1 - Synthesis and enantioselective enzymatic hydrolysis of rac-dimethylphenyl[1-(phenylacetamido)- ethyl]silane
N2 - Racemic dimethylphenyl(l-(phenylacetamido)ethyl)silane [rac-5) has been made by a four-step synthesis starting from (chloromethyl)dimethylphenylsilane [PhMe\(_2\)SiCH2Cl (1) ~ PhMe\(_2\)SiCH(Cl)Me (rac-2) - PhMe\(_2\)SiCH(l)Me (rac-3) - PhMe2SiCH(NH2)Me (rac-4) ~ PhMe\(_2\)SiCH[N(H)C(O)CH\(_2\)Ph]Me ( rac-5); total yield 41% ). Enantioselective enzymatic hydrolysis of rac-5, catalyzed by immobilized penicillin G acylase (E.C. 3.5.1.11) from Escherichia coli 5K (pHM 12), gave (R)-(1- aminoethyl)dimethylphenylsilane [( R )-4] in 40% yield with an enantiomeric purity of 92% ee.
KW - Anorganische Chemie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64153
ER -
TY - JOUR
A1 - Tacke, Reinhold
A1 - Mahner, K.
A1 - Strohmann, C.
A1 - Forth, B.
A1 - Mutschler, E.
A1 - Friebe, T.
A1 - Lambrecht, G.
T1 - Cyclohexyl(4-fluorophenyl)(3-piperidinopropyl)silanol (p-fluoro-hexahydro-sila-difenidol, p-F-HHSiD) and derivatives: synthesis and antimuscarinic properties
N2 - Four different syntheses of the potent and selective muscanruc antagonist cyclohexyl( 4- fluorophenyl)(3-piperidinopropyl)silanol ( p-fluoro-hexahydro-sila-difenidol, p-F-HHSiD (2b); isolated as hydrochloride 2b· HCl) are described (starting materials: (CH\(_3\)O)\(_2\)SiCH\(_2\)CH\(_2\)CH\(_2\)Cl and Si(OCH\(_3\))\(_4\) ). In addition, the synthesis of the corresponding carbon analogue p-fluoro-hexahydro-difenidol ( p-F-HHD (2a); isolated as 2a· HCI) and the syntheses of three p-F-HHSiD derivatives (3-5), with a modified cyclic amino group, are reported (3: piperidinojpyrrolidino exchange, isolated as 3· HCI; 4: piperidinoj hexamethylenimino exchange, isolated as 4 · HCl; 5: quaternization of 2b with methyl iodide). The chiral compounds 2a, 2b, 3, 4 and 5 were prepared as racemates. In functional pharmacological studies, 3-5 behaved as simple competitive antagonists at musearlnie Ml receptors in rabbit vas deferens, M2 receptors in guinea-pig atria, and M3 receptors in guinea-pig ileal smooth rnuscle. The pyrrolidino (3) and hexamethylenimino (4) analogues of the parent drug p-F-HHSiD (2b) displayed the highest affinity for Ml and M3 receptors (pA\(_2\) values: 7.0-7.4) but exhibited lower affinity for cardiac M2 receptors (pA\(_2\) : 5.9 and 6.0). Their affinity profile (Ml- M3 > M2) is different from that of p-F-HHSiD (2b) (M3 > Ml > M2), but qualitatively very similar tothat of p-F-HHD (2a). The methiodide 5 exhibited the highest affinity for Ml receptors (pA\(_2\) : 8.5) but lower affinity for M2 and M3 receptors by factors of 5.6 and 3.6, respectively.
KW - Anorganische Chemie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64162
ER -
TY - JOUR
A1 - Haas, Albert
A1 - Brehm, Klaus
A1 - Kreft, Jürgen
A1 - Goebel, Werner
T1 - Cloning, characterization, and expression in Escherichia coli of a gene encoding Listeria seeligeri catalase, a bacterial enzyme highly homologous to mammalian catalases
N2 - A gene coding for catalase (hydrogen-peroxide:hydrogen-peroxide oxidoreductase; EC 1.11.1.6) of the grain-positive bacterium Listeria seeligeri was cloned from a plasmid library of EcoRI-digested chromosomal DNA, with Escherichia coli DHSa as a host. The recombinant catalase was expressed in E. coli to an enzymatic activity approximately SO times that of the combined E. coli catalases. The nucleutide sequence was determined, and the deduced amino acid sequence revealed 43.2% amino acid sequence identity between bovine liver catalase and L. seeligeri catalase. Most of the amino acid residues which are involved in catalytic activity, the formation of the active center accession channel, and heme binding in bovine liver catalase were also present in L. seeligeri catalase at the corresponding positions. The recombinant protein contained 488 amino acid residues and had a calculated molecular weight of 55,869. The predicted isoelectric point was 5.0. Enzymatic and genetic analyses showed that there is most probably a single catalase of this type in L. seeligeri. A perfect 21-bp inverted repeat, which was highly homologous to previously reported binding sequences of the Fur (ferric uptake regulon) protein of E. coli, was detected next to the putative promoter region of tbe L. seeligeri catalase gene.
KW - Biologie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60536
ER -
TY - JOUR
A1 - Markgraf, J. H.
A1 - Cort, J. R.
A1 - Davis, H. A.
A1 - Lindeman, N. I.
A1 - Myers, C. R.
A1 - Kraft, A.
A1 - Christl, Manfred
T1 - Strained Heterocyclic Systems. 20. Basicities of Bicyclic Quinoxalines
N2 - No abstract available
KW - Organische Chemie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58584
ER -
TY - JOUR
A1 - Schülein, Ralf
A1 - Kreft, Jürgen
A1 - Gonski, Sigrid
A1 - Goebel, Werner
T1 - Preprosubtilisin Carlsberg processing and secretion is blocked after deletion of amino acids 97-101 in the mature part of the enzyme
N2 - During an investigation into the substrate specificity and processing of subtilisin Carlsberg from Bacillus licheniformis, two major independent findings were made: (i) as has been shown previously, a stretch of five amino acids (residues 97-101 of the mature enzyme) that loops out into the binding cleft is involved in substrate binding by subtilisin Carlsberg. In order to see whether this loop element also determines substrate specificity, the coding region for these five amino acids was deleted from the cloned gene for subtilisin Carlsberg by site-directed mutagenesis. Unexpectedly the resulting mutant preproenzyme (P42c, Mr=42 kDa) was not processed to the mature form (Mr = 30 kDa) and was not released into the medium by a proteasedeficient B. subtilis host strain; rather, it accumulated in the cell membrane. This result demonstrates that the integrity of this loop element, which is very distant from the processing cleavage sites in the preproenzyme, is required for secretion of subtilisin Carlsberg. (ii) In culture supernatants from B. subtilis harbouring the cloned wild-type subtilisin Carlsberg gene the transient appearance (at 0-3 h after onset of stationary phase) of a processing intermediate (P38c, Mr = 38 kDa) oftbis protease could be demonstrated. P38c very probably represents a genuine proform of subtilisin Carlsberg.
KW - Biologie
KW - Bacillus
KW - Proenzyme
KW - Subtilisin maturation
KW - Site-directed mutagenesis
KW - Subtilisin Carlsberg
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60577
ER -
TY - JOUR
A1 - Bentley, T. W.
A1 - Christl, Manfred
A1 - Norman, S. J.
T1 - Methanesulfonate/p-Nitrobenzoate and p-Toluenesulfonate/p-Nitrobenzoate Rate Ratios. Solvolyses of 1-Adamantyl and Benzhydryl Substrates
N2 - No abstract available
KW - Organische Chemie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58599
ER -
TY - JOUR
A1 - Vortkamp, A.
A1 - Thias, U.
A1 - Gessler, Manfred
A1 - Rosenkranz, W.
A1 - Kroisel, P. M.
A1 - Tommerup, N.
A1 - Kruger, G.
A1 - Gotz, J.
A1 - Pelz, L.
A1 - Grzeschik, Karl-Heinz
T1 - A somatic cell hybrid panel and DNA probes for physical mapping of human chromosome 7p
N2 - No abstract available
KW - Biochemie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59217
ER -
TY - JOUR
A1 - Jaiswal, Neelam
A1 - Lambrecht, Günter
A1 - Mutschler, Ernst
A1 - Tacke, Reinhold
A1 - Malik, Kafait U.
T1 - Pharmacological characterization of the vascular muscarinic receptors mediating relaxation and contraction in rabbit aorta
JF - Journal of Pharmacology and Experimental Therapeutics
N2 - Studies were performed in the rabbit aortic rings, precontracted with norepinephrine, to determine the subtype(s) of muscarinic receptors involved in endothelium-dependent relaxation and contraction in the absence of endothelium elicited by cholinergic stimuli. Acetylcholine (ACh) and arecaidine propargyl ester (APE), a M2 and M3 agonist, produced a dose-dependent relaxation and contraction in endothelium-intact and endothelium-denuded rabbit aortic rings, respectively. Both of these responses were blocked by the muscarinic receptor antagonist atropine. M1 selective agonist McN-A-343 [4-[N-(3-chlorophenyl)carbamoyloxy]-2-butinyltrimethylammonium+ ++ chloride] did not produce any effect on the tone of precontracted aortic rings. ACh- and APE-induced relaxation in aortic rings with intact endothelium was selectively blocked by M3 receptor antagonists hexahydrosila-difenidol and p-fluoro-hexahydro-sila-difenidol (pA2 of 7.84 and 7.18) but not by M1 antagonist pirenzepine or M2 receptor antagonists AF-DX 116 [11-(2-[(diethylamino)methyl]- 1-piperidinyl]acetyl)-5, 11-dihydro-6H-pyrido-[2,3-b][1,4]-benzo-diazepin-6-one] and methoctramine. ACh- and APE-induced contraction was inhibited by M2 receptor antagonists AF-DX 116 and methoctramine (pA2 of 7.11 and 6.71) but not by pirenzepine, hexahydro-sila-difenidol or p-fluoro-hexahydro-sila-difenidol. ACh- and APE-induced relaxation or contraction were not altered by nicotinic receptor antagonist hexamethonium or cyclooxygenase inhibitor indomethacin. These data suggest that relaxation elicited by cholinergic stimulin in endothelium-intact aortic rings is mediated via release of endothelium-derived relaxing factor consequent to activation of M3 receptors located on endothelial cells, whereas the contraction in aortic rings denuded of their endothelium is mediated via stimulation of M2 receptors located on smooth muscle cells.
KW - (4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium chloride/pharmacology
KW - acetylcholine
KW - animals
KW - antihypertensive agents / pharmacology
KW - aorta, abdominal / drug effects
KW - aorta, abdominal / physiology
KW - aorta, abdominal / ultrastructure
KW - arecoline/analogs & derivatives
KW - arecoline
KW - atropine
KW - diamines
KW - endothelium, vascular / drug effects
KW - endothelium, vascular / physiology
KW - hexamethonium
KW - hexamethonium compounds
KW - indomethacin
KW - male
KW - muscarinic antagonists
KW - muscle contraction
KW - muscle relaxation
KW - norepinephrine
KW - parasympatholytics
KW - piperidines
KW - pirenzepine
KW - rabbits
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128358
VL - 258
IS - 3
ER -
TY - JOUR
A1 - Gigstad, Kenneth M.
A1 - Ricci JR., John S.
A1 - Markgraf, J. Hodge
A1 - Christl, Manfred
A1 - Kraft, Arno
T1 - Strained Heterocyclic Systems : 18. Structure of 1,2,3-Methylidyne-2,3-dihydro-1H-cyclopenta[b]quinoxaline
N2 - No abstract available
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41645
SN - 0108-2701
ER -
TY - CHAP
A1 - Hommers, Wilfried
A1 - Anderson, Norman H.
T1 - Moral algebra of harm and recompense
N2 - No abstract available
KW - Informationsverarbeitung / Kognition
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-44046
ER -
TY - JOUR
A1 - Dabauvalle, Marie-Christine
A1 - Loos, Karin
A1 - Merkert, Hilde
A1 - Scheer, Ulrich
T1 - Spontaneous assembly of pore complex-containing membranes ("Annulate lamellae") in Xenopus egg extract in the absence of chromatin
N2 - No abstract available
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32797
ER -
TY - JOUR
A1 - Becker, Charles R.
A1 - Wu, Y. S.
A1 - Waag, A.
A1 - Kraus, M. M.
A1 - Landwehr, G.
T1 - The orientation independence of the CdTe-HgTe valence band offset as determined by x-ray photoelectron spectroscopy
N2 - No abstract available
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30784
ER -
TY - JOUR
A1 - Moll, Heidrun
A1 - Röllinghoff, Martin
T1 - T-cell reactivity to purified lipophosphoglycan from Leishmania major: A model for analysis of the cellular immune response to microbial carbohydrates.
N2 - The major macromolecule on the surface o/Leishmania majorpromastigotes is a lipophosphoglycan (LPG). This glycoconjugate plays a key role in determining infectivity and survival of para-sites in the mammalian host cell. In addition, L. major LPG is able to induce a host-protective immune response. In this article, we summarise the evidence for recognition of highly purified LPG by T cells and we discuss the potential mechanisms of T-cell Stimulation by this non-protein antigen.
KW - Leishmania
KW - T lymphocytes
KW - glycosyl phosphatidyl-inostitols.
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33022
ER -
TY - JOUR
A1 - Van Die, I.
A1 - Kramer, C.
A1 - Hacker, Jörg
A1 - Bergmans, H.
A1 - Jongen, W.
A1 - Hoekstra, W.
T1 - Nucleotide sequence of the genes coding for minor fimbrial subunits of the F1C fimbriae of Escherichia coli
N2 - F 1 C fimbriae allow uropathogenic Escherichia coli to adhere to specific epithelial surfaces. This adhesive property is probably due to the presence of minor fimbrial components in F1C fimbriae. The foe gene cluster encoding F1C fimbriae has been cloned, as described previously. Here we present the nucleotide sequence (2081 bp) coding for the F 1 C minor fimbria I subunits. The structural genes code for polypeptides of 175 (FocF), 166 (FocG), and 300 (FocH) amino acids. The deduced amino acids of the F 1 C minor subunits were compared with the reported sequences of the minor subunits of other types of fimbriae. The data show that the Foc minor subunits are highly homologous to the corresponding Sfa proteins, whereas homology to the minor subunits of type 1 and P fimbriae is much lower.
KW - Pilus
KW - Escherichia coli
KW - Adherence
KW - Urinary tract
KW - Foc protein
KW - Minor subunits
KW - Sequencing
KW - Homology
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40353
ER -
TY - JOUR
A1 - Lück, P. Christian
A1 - Bender, Larisa
A1 - Ott, Manfred
A1 - Helbig, Jürgen H.
A1 - Hacker, Jörg
T1 - Analysis of Legionella pneumophila serogroup 6 strains isolated from a hospital warm water supply over a three-year period by using genomic long-range mapping techniques and monoclonal antibodies
N2 - Over a period of 3 years, Legionella pneumophila serogroup 6 strains were isolated from warm water outlets and dental units in the Dental Faculty and from the Surgery and Internal Medicine Clinics at the University of Dresden, Dresden, Germany. In the bacteriological unit of the above-mentioned facility, L. pneumophila serogroups 3 and 12 were grown frl,)m warm water specimens. The medical facilities are located in separate buildings connected with a ring pipe warm water system. All L. pneumophila serogroup 6 strains isolated from the warm water supply reacted with a serogroup-specific monoclonal antibody, but not with two other monoclonal antibodies which are subgroup specific, reacting with other serogroup 6 strains. The NolI genomic profiles obtained by pulsed-field gel electrophoresis of 25 serogroup 6 strains isolated from the Dental Faculty over a 3-year period, 1 isolate from the Internal Medicine Clinic, and 4 strains from the Surgery Clinic were identical. Furthermore, all these strains hybridized with a 3OO-kb NolI fragment when a legiolysin (lIy)-specific DNA probe was used. The NolI pattern, however, differed from those of six serogroup 6 strains of other origins, one serogroup 12 strain from the bacteriological unit, and another six unrelated strains of serogroups other than serogroup 6. L. pneumophila serogroup 6 strains which can be divided into only two subgroups by the use of monoclonal antibodies are differentiated in at least six Noli cleavage types obtained by pulsed-field electrophoresis.
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40392
ER -
TY - JOUR
A1 - Fischer, Dagmar
A1 - Weißenberger, Dieter
A1 - Scheer, Ulrich
T1 - Assigning functions to nucleolar structures
N2 - Nucleoli provide the fascinating possibility of linking morphologically distinct structures such as those seen in the electron microscope with biochemical f eatures of the formation and step wise maturation of ribosomes. Localization of proteins by immunocytochemistry and of rRNA genes and their transcripts by in situ hybridization has greatly improved our understanding of the structural-functional relationships of the nucleolus. The present review describes some recent results obtained by electron microscopic in situ hybridization and argues that this approach has the potential to correlate each step of the complex pre-rRNA maturation pathway with nucleolar structures. Evidence is accumulating that the nucleolus-specific U3 snRNPs (small nuclear ribonucleoprotein particles) participate in rRNA processing events, similar to the role played by the nucleoplasmic snRNPs in mRNA maturation. The intranucleolar distribution of U3 snRNA is consistent with the view that it is involved in both early and late stages of pre-rRNA processing.
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34258
ER -
TY - JOUR
A1 - Bringmann, Gerhard
A1 - Zagst, Rainer
A1 - Schöner, Bernd
A1 - Busse, Holger
A1 - Hemmerling, Martin
A1 - Burschka, Christian
T1 - Acetogenic Isoquinoline Alkaloids. XXIII. Structure of the Naphthyl Isoquinoline Alkaloid Dioncophylline A
N2 - No abstract available
KW - Chemie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31331
ER -
TY - JOUR
A1 - Dandekar, Thomas
T1 - Yeast U3 localization and correct sequence (snR17a) and promotor activity (snR17b) identified by homology search
N2 - No abstract available
KW - yeast U3 localization
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29781
ER -
TY - JOUR
A1 - Dandekar, Thomas
A1 - Tollervey, D.
T1 - Thirty-three nucleotides of 5' flanking sequence including the TATA box are necessary and sufficient for efficient U2 snRNA transcription in Schizosaccharomycespombe
N2 - No abstract available
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29959
ER -
TY - JOUR
A1 - Dandekar, Thomas
A1 - Stripecke, Renata
A1 - Gray, Nicola K.
A1 - Goossen, Britta
A1 - Constable, Anne
A1 - Johansson, Hans E.
A1 - Hentze, Matthias W.
T1 - Identification of a novel iron-responsive element in murine and human erythroid \(\delta\)-aminolevulinic acid synthase mRNA
N2 - No abstract available
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29929
ER -
TY - JOUR
A1 - Dandekar, Thomas
A1 - Argos, Patrick
T1 - Chaperonin-mediated protein folding at the surface of groEL through a "molten globule" intermediate
N2 - No abstract available
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29939
ER -
TY - JOUR
A1 - Stöckli, K. A.
A1 - Lililien, L. E.
A1 - Näher- Noé, M.
A1 - Breitfeld, G.
A1 - Hughes, Richard A.
A1 - Raff, M. C.
A1 - Thoenen, Hans
A1 - Sendtner, Michael
T1 - Regional distribution, developmental changes, and cellular localization of CNTF-mRNA and protein in the rat brain
N2 - Ciliary neurotrophic factor (CNTF) is a potent survival molecule for a variety of embryonic neurons in culture. The developmental expression of CNTF occurs clearly after the time period of the physiological cell death of CNTF-responsive neurons. This, together with the sites of expression, excludes CNTF as a target-derived neuronal survival factor, at least in rodents. However, CNTF also participates in the induction of type 2 astrocyte differentiation in vitro. Here we demonstrate that the time course of the expression of CNTF-mRNA and protein in the rat optic nerve (as evaluated by quantitative Northern blot analysis and biological activity, respectively) is compatible with such a glial differentiation function of CNTF in vivo. We also show that the type 2 astrocyte-inducing- activity previously demonstrated in optic nerve extract can be precipitated by an antiserum against CNTF. Immunohistochemical analysis of astrocytes in vitro and in vivo demonstrates that the expression of CNTF is confined to a subpopulation of type 1 astrocytes. The olfactory bulb of adult rats has comparably high levels of CNTF to the optic nerve, and here again, CNTF-immunoreactivity is localized in a subpopulation of astrocytes. However, the postnatal expression of CNTF in the olfactory bulb occurs later than in the optic nerve. In other brain regions both CNTF-mRNA and protein levels are much lower.
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31172
ER -
TY - JOUR
A1 - Maschwitz, Ulrich
A1 - Fiala, Brigitte
A1 - Moog, J.
A1 - Saw, L. G.
T1 - Two new myrmecophytic associations from the Malay Peninsula: ants of the genus Cladomyrma as partners of Saraca thaipingensis and Crypteronia griffithii
N2 - In Peninsular Malaysia the trees Saraca thaipingensis (Caesalpiniaceae) and Crypteronia griffithii (Crypteroniaceae) are inhabited by ants. In the vicinity ofGombak, near Kuala Lumpur, the hollow internodes of young Saraca thaipingensis plants are colonized mainly by two Cladomyrma species. In larger trees a Crematogaster sp. is also found. Crypteronia griffithii is inhabited by a third species of Cladomyrma. None of these species is conspecific with any of the three Cladomyrma taxa so far described. The colonies are founded by single mated queens, which have a conspicuous, sphecid wasp-like behaviour when searching for host plants and nest sites. They chew holes into the plant intern odes and hollow them out to provide nest sites. Coccids and pseudococcids are cultivated within the internodes. The homopterans are not carried by queens on their nuptial flights. They apparently find their way by themselves into the cavities or are perhaps carried there by the worker ants. The Cladomyrma ants on Crypteronia are not aggressive, in contrast to those on Saraca thaipingensis. The relationship of Crypteronia with ants seems to be obligatory, whereas Saraca was only partly colonized by Cladomyrma. The interaction of Saraca with Crematogaster sp. is loose and facultative, since the Crematogaster sp. also lives on other tree species. Our studies have now revealed four Cladomyrma spp. which are regularly associated with plants. The genus therefore seems to have an entirely myrmecophytic way of life.
KW - Myrmecophytism ; Malaysia ; trophobionts ; colony foundation ; Cladomyrma
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32992
ER -
TY - JOUR
A1 - Wu, Y.S.
A1 - Becker, Charles R.
A1 - Waag, A.
A1 - Kraus, M. M.
A1 - Bicknell-Tassius, R. N.
A1 - Landwehr, G.
T1 - Correlation of the Cd-to-Te ratio on CdTe surfaces with the surface structure
N2 - We report here that reconstruction on (100), (1lIlA, and (1l1lB CdTe surfaces is either C(2X2), (2X2), and (l X I) or (2X I), (l X I), and (l X I) when they are Cd or Te stabilized, respectively. There is a mixed region between Cd and Te stabilization in which the reflected high-energy electron-diffraction (RHEED) patterns contain characteristics of both Cd- and Te-stabilized surfaces. We have also found that the Cd-to-Te ratio of the x-ray photoelectron intensities of their 3d\(_{3/ 2}\) core levels is about 20% larger for a Cd-stabilized (1lIlA, (1lIlB, or (100) CdTe surface than for a Te-stabilized one. According to a simple model calculation, which was normalized by means of the photoelectron intensity ratio of a Cd-stabilized (lll)A and aTe-stabilized (1l1lB CdTe surface, the experimental data for CdTe surfaces can be explained by a linear dependence of the photoelectron-intensity ratio on the fraction of Cd in the uppermost monatomic layer. This surface composition can be correlated with the surface structure, i.e., the corresponding RHEED patterns. This correlation can in turn be employed to determine Te and Cd evaporation rates. The Te reevaporation rate is increasingly slower for the Te-stabilized (Ill) A, (l1l)B, and (100) surfaces, while the opposite is true for Cd from Cd-stabilized (Ill) A and (Ill)B surfaces. In addition, Te is much more easily evaporated from all the investigated surfaces than is Cd, if the substrate is kept at normal molecular-beam-epitaxy growth temperatures ranging from 2oo·C to 300 ·C.
KW - Festkörperphysik
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-37789
SN - 0163-1829
ER -
TY - JOUR
A1 - Ulrichs, Karin
A1 - Müller-Ruchholtz, Wolfgang
T1 - Modulation of pancreatic islet allo immunogenicity and immunobiological in vitro and in vivo consequences
N2 - No abstract available.
KW - Immunobiologie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78261
ER -
TY - JOUR
A1 - Krzymanski, M.
A1 - Waaga, A. M.
A1 - Ulrichs, Karin
A1 - Müller-Ruchholtz, Wolfgang
T1 - Long-standing rat kidney graft survival by a combination of organ perfusion with MHC class II monoclonal antibody and immunosuppression with reduced doses of 15-deoxyspergualin.
N2 - No abstract available
KW - Niere
KW - Ratte
KW - MHC Klasse II
KW - kidney
KW - rat
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64442
ER -
TY - JOUR
A1 - Schlupp, I.
A1 - Parzefall, J.
A1 - Schartl, Manfred
T1 - Male mate choice in mixed bisexual/-unisexual breeding complexes of Poecilia (Teleostei: Poeciliidae)
N2 - The livebearing all-female fish Poecilia formosa reproduces by gynogenesis, a modified form of parthenogenesis. P. formosa forms at least two breeding complexes: in its northern range it exists sympatrically with Poecilia latipinna and in its southern range with Poecilia mexicana. Differences between these complexes and their possible origin are discussed. Embryogenesis is triggered by sperm of males of these closely related sympatric species. Because inheritance is stricdy maternal, from the male point of view energy and time invested are totally lost. In this study we wanted to elucidate whether males are able to distinguish between conspecific and parasitic females. It could be shown that males are able to distinguish females optically, but that this ability was obscured as soon as chemical and/or tactile contact was possible. Furthermore, we found that females in an attractive phase of their sexual cycle are always preferred, regardless of species. This is possibly the mechanism by which parasitic females obtain the matings they need to reproduce.
KW - Poecilia (Teleostei: Poeciliidae)
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-80309
ER -
TY - JOUR
A1 - Malitschek, B.
A1 - Schartl, Manfred
T1 - Rapid identification of recombinant baculoviruses using PCR
N2 - no abstract available
KW - PCR
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-80328
ER -
TY - JOUR
A1 - Lohse, Martin J.
A1 - Klotz, Karl-Norbert
A1 - Schwabe, Ulrich
T1 - Mechanism of A2 adenosine receptor activation. I. Blockade of A2 adenosine receptors by photoaffinity labeling
N2 - It has previously been shown that covalent incorporation of the photoreactive adenosine derivative (R)-2-azido-N6-p-hydroxyphenytisopropyladenosine [(R)-AHPIA] into the A, adenosine receptor of intact fat cells leads to a persistent activation of this receptor, resulting in a reduction of celular cAMP Ieveis [Mol. Pharmacol. 30:403-409 (1986)]. In contrast, covalent incorporation of (R)-AHPIA into human platelet membranes, which contain only stimulatory A2 adenosine receptors, reduces adenytate cyclase Stimulation via these receptors. This effect of (R)-AHPIA is specific for the A2 receptor and can be prevented by the adenosine receptor antagonist theophylline. Binding studies in-dicate that up to 90% of A2 receptors can be blocked by photoincorporation of (R)-AHPIA. However, the remaining 10-20% of A2 receptors are sufficient to mediate an adenylate cyclase Stimulation of up to SOOk of the control value. Similarly, the activation via these 10-20% of receptors occurs with a halflife that is only 2 times Ionger than that in control membranes. This indicates the presence of a receptor reserve, with respect to both the extent and the rate of adenytate cyclase Stimulation. These observations require a modification of the models of receptor-adenytate cyclase coupling, which is described in the accompanying paper [Mol. Pharmacol. 39:524-530 (1991)].
KW - Adenosinrezeptor
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86073
ER -
TY - CHAP
A1 - Spielmann, W. S.
A1 - Arend, L. J.
A1 - Klotz, Karl-Norbert
A1 - Schwabe, U.
T1 - Adenosine control of the renal Collecting tubule: receptors and signaling
N2 - No abstract available.
KW - Adenosin
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86129
ER -
TY - JOUR
A1 - Wilhelm, Gernot
A1 - Zaccagnini, Carlo
T1 - Excavations at Tell Karrana 3 (1985 and 1986)
N2 - no Abstract available
KW - Tell Karrana
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-85963
ER -
TY - JOUR
A1 - Berger, Susanne
A1 - Ellersiek, Ulrike
A1 - Steinmüller, Klaus
T1 - Cyanobacteria contain a mitochrondrial complex I-homologous NADH-dehydrogenase
N2 - Thylakoid and cytoplasmic membranes of the cyanobacterium Syncchocystis sp. PCC 6803 were purified by sucrose gradient centrifugation. Both membranes oxidize NADH in a rotenone-sensitive reaction. Antibodies prepared against psbG/ndhKand ndhJ fusion proteins detect the corresponding polypeptides in both membrane preparations. This demonstrates that a NADH-dehydrogenase, homologous to the mitochondrial NADHubiquinone-oxidoreductase (complex I of the respiratory chain) is present in cyanobacteria, The NADH-dehydrogenase can be solubilized with the detergent /-D-dodecylmaltoside. Sedimentation analysis of the solubilized enzyme on a sucrose gradient indicates that it is a multisubunit protein complex.
KW - Respiratory chain
KW - NADH-dehydrogenase
KW - Cyanobacteria
KW - Synechocystis 6803
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31223
ER -
TY - JOUR
A1 - Heinsen, Helmut
A1 - Heinsen, Y. L.
T1 - Serial thick, frozen, gallocyanin stained sections of human central nervous system
N2 - A rapid method for macroscopic and microscopic investigation of human CNS is proposed. After fonnalin fixation, gelatin or agarose embedding, and cryoprotective treatment, frozen human spinal cords, brainstems, or hemispheres can be serially cut into 0.7 mm thick slices. Stained with gallocyanin-chromalum, these slices facilitate cytoarchitectonic, neuropathologic, and quantitative examination. Regions of interest from parallel fonnalin-stored unstained slices can be embedded into paraffin and stained by any irnrnunocytologic and histologic stain compatible with fonnalin fixation and paraffin embedding.
KW - CNS
KW - comparative anatomy
KW - cytoarchitectonics
KW - neuroimaging
KW - neuropathology
KW - Nissl stain
KW - quantitative anatomy
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45741
ER -
TY - CHAP
A1 - Ellgring, Johann Heinrich
T1 - Introduction. The use of Video for behavior description and intervention
N2 - No abstract available
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42019
ER -
TY - JOUR
A1 - Sendtner, Michael
A1 - Arakawa, Yoshihiro
A1 - Stöckli, Kurt A.
A1 - Kreutzberg, Georg W.
A1 - Thoenen, Hans
T1 - Effect of ciliary neurotrophic factor (CNTF) on motoneuron survival
N2 - We have demonstrated that the extensive degeneration of motoneurons in the rat facial nucleus after transection of the facial nerve in newborn rats can be prevented by local ciliary neurotrophic factor (CNTF) administration. CNTF differs distinctly from known neurotrophic molecules such as NGF, BDNF and NT-3 in both its molecular characteristics (CNTF is a cytosolic rather than a secretory molecule) and its broad spectrum of biological activities. CNTF is expressed selectively by Schwann cells and astrocytes of the peripheral and central nervous system, respectively, but not by target tissues of the great variety of CNTF -responsive neurons. CNTF mRNA is not detectable by Northern blot or PCR analysis during embryonic development and immediately after birth. However, during the second post-natal week, a more than 30-fold increase in CNTF mRNA and pro tein occurs in the sciatic nerve. Since the period of low CNTF levels in peripheral nerves coincides with that of high vulnerability of motoneurons (i.e. axonallesion results in degeneration of motoneuron cell bodies), insufficient availability of CNTF may be the reason for the rate of lesioninduced cell death of early post-natal motoneurons. Highly enriched embryonic chick motoneurons in culture are supported at survival rates higher than 60% by CNTF, even in single cell cultures, indicating that CNTF acts directly on motoneurons. In contrast to CNTF, the members of the neurotrophin gene family (NGF, BDNF and NT-3) do not support the survival of motoneurons in culture. However, aFGF and bFGF show distinct survival activities which are additive to those of CNTF, resulting in the survival of virtually all motoneurons cultured in the presence of CNTF and bFGF.
KW - motoneurons
KW - ciliary neurotrophic factor
KW - CNTF
KW - nerve lesion
KW - rat
KW - chick
KW - neurotrophic factor
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33048
ER -
TY - JOUR
A1 - Fiala, Brigitte
A1 - Maschwitz, Ulrich
T1 - Extrafloral nectaries in the genus Macaranga (Euphorbiaceae) in Malaysia: comparative studies of their possible significance as predispositions for myrmecophytism.
N2 - So me species of the paleotropical tree genus Macaranga (Euphorbiaceae) live in elose association with ants. Thc genus comprises the full range of species from those not regularly inhabited by ants to obligate myrmecophytes. In Malaysia (peninsular and Borneo) 23 ofthe 52 species areknown to be ant-associated (44%). The simplest structural adaptation of plants to attract ants are extrafloral nectaries. We studied the distribution of extraflural nectaries in the genus Macaranga to assess the significance of this character as a possible predisposition for the evolution of obligate myrmecophytism. All species have marginal glands on the leaves. However, only the glands of nonmyrmecophytic species function as nectaries, whereas liquids secreted by these glands in myrmecophytic species did not contain sugar. Some non-myrmecophytic Macaranga and transitional Macaranga species in addition have extrafloral nectaries on the leaf blade near the petiole insertion. All obligatorily myrmecophytic Macaranga species, however, lack additional glands on the lamina. The non-myrmecophytic species are visited by a variety of different ant species, whereas myrmecophytic Macaranga are associated only with one specific ant-partner. Since these ants keep scale insects in the hollow sterns, reduction of nectary production in ant-inhabited Macaranga seems to be biologically significant. We interpret this as a means of (a) saving the assimilates and (b) stabilization of maintenance of the association's specificity. Competition with other ant species for food rewards is avoided and thereby danger ofweakening the protective function ofthe obligate antpartner for the plant is reduced. A comparison with other euphorb species living in the same habitats as Macaranga showed that in genera in which extrafloral nectaries are widespread, no myrmecophytes have evolved. Possession of extrafloral nectaries does not appear to be essential for the development of symbiotic ant-plant interactions. Other predispositions such as nesting space might have played a more important role.
KW - Macaranga
KW - extrafloral nectaries
KW - ant-plant interactions
KW - evolution of myrmecophytism
KW - Malaysia
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42863
ER -
TY - JOUR
A1 - Kaupmann, Klemens
A1 - Sendtner, Michael
A1 - Stöckli, Kurt A.
A1 - Jockusch, Harald
T1 - The gene of ciliary neurotrophic factor (cntf) maps to murine chromosome 19 and its expression is not affected in the hereditary motoneuron disease 'wobbler' of the mouse
N2 - The cDNA for ciliary neurotrophic factor (CNTF), a polypeptide involved in the survival of motoneurons in mammals, has recently been cloned (Stöckli et al., Nature, 342, 920 - 923, 1989; Lin et al. Science, 246, 1023 - 1025, 1989). We have now localized the corresponding gene Cntf to chromosome 19 in the mouse, using an interspecific cross between Mus spretus and Mus musculus domesticus. The latter was carrying the gene wobbler (wr) for spinal muscular atrophy. DNA was prepared from backcross individuals and typed for the segregation of species-specific Cntf restriction fragments in relation to DNA markers of known chromosomal location. The M.spretus allele of Cntf cosegregated with chromosome 19 markers and mapped closely to Ly-1, to a region of mouse chromosome 19 with conserved synteny to human chromosome 11q. Cntf is not linked to wr, and the expression of CNTF mRNA and protein appears close to normal in facial and sciatic nerves, of affected (wr/wr) mice, suggesting that motoneuron degeneration of wobbler mice has its origin in defects other than reduced CNTF expression.
KW - Mus spretus
KW - interspeific backcross
KW - spinal muscular atrophy
KW - linkage
KW - restriction fragment length polymorphism
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42626
ER -
TY - JOUR
A1 - Dabauvalle, Marie-Christine
A1 - Scheer, Ulrich
T1 - Assembly of nuclear pore complexes in Xenopus egg extract
N2 - No abstract available
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41194
ER -
TY - JOUR
A1 - Dandekar, Thomas
T1 - Olbers' Paradox (peer-reviewed scientific correspondence)
N2 - No abstract available
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31672
ER -
TY - JOUR
A1 - Wu, Y. S.
A1 - Becker, Charles R.
A1 - Waag, A.
A1 - Bicknell-Tassius, R. N.
A1 - Landwehr, G.
T1 - The effects of laser illumination and high energy electrons on molecular-beam epitaxial growth of CdTe
N2 - We report the results of a detailed investigation on the Te-stabilized (2 x 1) and the Cdstabilized c( 2 X 2) surfaces of ( 100) CdTe substrates. The investigation demonstrates for the first time that both laser illumination and, to a greater extent, high-energy electron irradiation increase the Te desorption and reduce the Cd desorption from ( 100) CdTe surfaces. Thus it is possible by choosing the proper growth temperature and photon or electron fluxes to change the surface reconstruction from the normally Te-stabilized to a Cd-stabilized phase.
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30795
ER -
TY - JOUR
A1 - Kaupp, Martin
A1 - Schleyer, P. v. R.
A1 - Stoll, H.
A1 - Preuss, H.
T1 - Pseudopotential Approaches to Ca, Sr and Ba Hybrides. Why are some Alkaline Earth MX\(_2\) Compounds Bent?
N2 - Quasirelativistic and nonrelativistic lo-valence-electronp seudopotentialsf or Ca, Sr, and Ba are presented. Results of calculations with 6s6p5d basis sets for MH, MH\(^+\) , and MH\(_2\), are compared with all-electron and 2-valence-electron pseudopotential calculations with and , without core-polarization potentials. The lo-valence-electron pseudopotential approach agrees well with all-electron calculations. It circumvents problems for the 2-valence-electron pseudopotentials arising from an incomplete separation of valence and subvalence shells in polar molecular systems due to strongly contracted occupied (n - 1 )-d orbitals. All higherlevel calculations show SrH\(_2\) and BaII\(_2\), to be bent with angles of - 140° and 120°, respectively, while CaH\(_2\) is linear with a flat potential-energy surface for the bending motion. The use of a core-polarization potential together with the 2-valence-electronp seudopotentiala pproach allows an investigation of the relative importance of core-polarization vs direct d-orbital bonding participation as reasons for the bent structures. The calculations strongly suggest that both contribute to the bending in SrH\(_2\) and BaII\(_2\). Even at the Hartree-Fock level of theory lovalence- electronp seudopotentialc alculations given reasonablea nglesw hen the potentialenergy surface is not exceedingly flat, and only moderately contracted basis sets including both compact d functions and diffuse p functions are used. The effect of core-valence correlation and the importance off functions also are discussed.
KW - Chemie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31646
ER -
TY - JOUR
A1 - Rettinger, Klaus
A1 - Burschka, Christian
A1 - Scheeben, Peter
A1 - Fuchs, Heike
A1 - Mosandl, Armin
T1 - Chiral 2-alkylbranched acids, esters and alcohols. Preparation and stereospecific flavour evaluation
N2 - Racemic 2-alkylbranched acids are transformed to diastereomeric derivatives with (S)-2-hydroxy-3-phenylpropionic acid-N-methylamide or (S)-(-)-l-phenylethylamine and separated by liquid chromatography to pure diastereoisomers, which are subsequently hydrolyzed to yield optically pure acids. Enantiomeric alcohols are generated by LiAlH4-reduction of the corresponding acids, esters are synthesized by different methods. The odour impression of the enantiomeric compounds is investigated.
KW - Säure
KW - Ester
KW - Alkohol
KW - 2-alkylbranched acids
KW - esters and alcohols
KW - flavour substances
KW - chirality and odour
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31898
ER -
TY - JOUR
A1 - Schüssler, Ulrich
A1 - Talarico, F.
T1 - Granulite facies rocks from the Ross orogenic belt, Northern-Victoria-Land, Antarctica
N2 - no abstract available
KW - Geographie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-81889
ER -
TY - JOUR
A1 - Gonzalez-Calero, G.
A1 - Cubero, A.
A1 - Klotz, Karl-Norbert
T1 - Characterization and photoaffinity labeling of A1 adenosine receptors in coated visicles form bovine brain
N2 - The antagonist (3 II ) DPCPX exhi bitcd a Kd of 0. 4 nM at coalcd vcsicles from bovine brain. Agonist compelition for ( 3 11) DPCPX bind in~ revcaled two affini ty slales for gonists. The pholoaffinity probe I25 I -AHPIA specifically labelled a band with a molecular weight of 35 Kd.
KW - Pharmakologie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86004
ER -
TY - JOUR
A1 - Schartl, Manfred
A1 - Erbelding-Denk, Claudia
A1 - Nanda, Indrajit
A1 - Schmid, Michael
A1 - Schröder, Johannes Horst
A1 - Epplen, Jörg T.
T1 - Mating success of subordinate males in a poeciliid fish species, Limia perugiae
N2 - No abstract available.
KW - Lebendgebärende Zahnkarpfen
KW - Perugia-Kärpfling
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86349
ER -
TY - JOUR
A1 - Adam, Dieter
A1 - Maueler, Winfried
A1 - Schartl, Manfred
T1 - Transcriptional activation of the melanoma inducing Xmrk oncogene in Xiphophorus
N2 - The melanoma inducing locus of Xiphophorus encodes a tumorigenic version of a novel putative receptor tyrosine kinase (Xmrk). To elucidate the mechanism of oncogenic activation of Xmrk, we compared the structure and expression of two oncogenic loci with the corresponding proto-oncogene. Only minor structural alterations were found to be specific for the oncogenic Xmrk genes. Marked overexpression of the oncogene transcripts in melanoma, which are approximately 1 kb shorter than the proto-oncogene transcript, correlates with the malignancy of the tumors. The tumor transcripts are derived from an alternative transcription start site that is used only in the oncogenic loci. Thus, oncogenic activation of the melanoma inducing Xmrk gene appears primarily to be due to novel transcriptional control and overexpression.
KW - Schwertkärpfling
KW - Onkogen
KW - Melanom
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-87584
ER -
TY - JOUR
A1 - Hannig, Gerhard
A1 - Ottilie, Sabine
A1 - Schartl, Manfred
T1 - Conservation of structure and expression of the c-yes and fyn genes in lower vertebrates
N2 - The src-gene family in mammals and birds consists of 9 closely related protein tyrosine kinases. We have cloned the c-yes and fyn bomologues of the src-family from the teleost fish Xiphophorus helleri. Both genes show a high degree of sequence conservation and exhibit all structural motifs diagnostic for functional src-like protein tyrosine kinases. Sequence comparisons revealed three domains (exon 2, exons 3--6, exons 7-12) which evolve at different rates. Both genes exhibit an identical expression pattern, with preferential expression in neural tissues. No transcripts of c-yes were found in liver wbich is contrary to the situation in higher vertebrales. In malignant melanoma, elevated Ieveis of c-yes andfyn were detected indicating a possible function during secondary steps of tumor progression for src-related tyrosine kinases.
KW - Konservierung
KW - Gen
KW - Niedere Wirbeltiere
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86723
ER -
TY - JOUR
A1 - Wilhelm, Gernot
T1 - A Hurrian Letter from Tell Brak
N2 - No abstract available.
KW - Tell Brak
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-85972
ER -
TY - CHAP
A1 - Epplen, J. T.
A1 - Ammer, H.
A1 - Epplen, C.
A1 - Kammerbauer, C.
A1 - Mitreiter, R.
A1 - Roewer, L.
A1 - Schwaiger, W.
A1 - Steimle, V.
A1 - Zischler, H.
A1 - Albert, E.
A1 - Andreas, A.
A1 - Beyermann, B.
A1 - Meyer, W.
A1 - Buitkamp, J.
A1 - Nanda, I.
A1 - Nürnberg, P.
A1 - Pena, S. D. J.
A1 - Pöche, H.
A1 - Sprecher, W.
A1 - Schartl, Manfred
A1 - Weising, K.
A1 - Yassouridis, A.
T1 - Oligonucleotide fingerprinting using simple repeat motifs: a convenient, ubiquitously applicable method to detect hypervariability for multiple purposes
N2 - A panel of simple repetitive oligonucleotide probes has been designed and tested for multilocus DNA fingerprinting in some 200 fungal, plant and animal species as well as man. To date at least one of the probes has been found to be informative in each species. The human genome, however, has been the major target of many fingerprintins studies. Using the probe (CAC)5 or (GTG)5, individualization of all humans is possible except for monozygotic twins. Paternity analyses are now perfonned on a routine basis by the use of multilocus fingerprints, inctuding also cases of deficiency, i.e. where one of the parents is not available for analysis. In forensie science stain analysis is feasible in all tissue remains containing nuc)eated cells. Depending on the degree of DNA degradation a variety of oligonucleotides are informative, and they have been proven useful in actual case work. Advantages in comparison to other methods including enzymatic DNA amplification techniques (PCR) are evident. Fingerprint patterns of tumors may be changed due to the gain or loss of chromosomes and/or intrachromosomal deletion and amplification events. Locus-specific probes were isolated from the human (CAC)5/( GTG)5 fingerprint with a varying degree of informativeness (monomorphic versus truly hypervariable markers). The feasibility of three different approaches. for the isolation of hypervariable mono-locus probes was evaluated. Finally, one particular mixed simple (gt)n(ga)m repeat locus in the second intron of the HLA-DRB genes has been scrutinized to allow comparison of the extent of exon-encoded (protein-) polymorphisms versus intronie bypervariability of simple repeats: adjacent to a single gene sequence (e.g. HLA-DRB1*0401) many different length alleles were found. Group-specific structures of basic repeats were identified within the evolutionarily related DRB alleles. As a further application it is suggested here that due to the ubiquitous interspersion of their targets, short probes for simple repeat sequences are especially useful tools for ordering genomic cosmid, yeast artificial chromosome and phage banks.
KW - DNS
KW - Fingerprint-Verfahren
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86371
ER -
TY - CHAP
A1 - Adam, D.
A1 - Schartl, A.
A1 - Andexinger, S.
A1 - Hölter, S.
A1 - Wilde, B.
A1 - Schartl, Manfred
T1 - Genetic factors in tumour formation: The melanoma-inducing gene of Xiphophorus
N2 - No abstract available.
KW - Humangenetik
KW - Tumor
KW - Entstehung
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86388
ER -
TY - JOUR
A1 - Schroten, Horst
A1 - Wolske, Anja
A1 - Plogmann, Ricarda
A1 - Hanisch, Franz-Georg
A1 - Hacker, Jörg
A1 - Uhlenbrück, Gerhard
A1 - Wahn, Volker
T1 - Binding of cloned S-fimbriated E. coli to human buccal epithelial cells-different inhibition of binding by neonatal saliva and adult saliva.
N2 - Investigations were carried out on the adhesion of cloned S-fimbriated E. coli, labelled with fluoresceinisothiocyanate (FITC) to human buccal epithelial cells. Fluorescence microscopic analysis revealed binding of bacteria to 75-95% of epithelial cells. Inhibition experiments with fetuin, a 1-acid glycoprotein and N-acetyl neuraminic acid confirmed the specificity of bacterial binding to sialoglycoproteins. Further studies using saliva as an inhibitor resulted in a 4-5 times stronger binding inhibition by newborn saliva in comparison to adult saliva coinciding with a 4-5 times higher content of total N-acetyl neuraminic acid in samples of newborn saliva. In Western blot analysis sialoglycoprotein bands with a molecular weight >200 kD reacting with wheat germ agglutinin (WGA), were only identified in samples of newborn saliva. These bands are classified as mucins on account of molecular weight and staining. These data suggest that saliva mucins could represent a major defense mechanism against bacterial infections at a stage of ontogeny where the secretory IgAsystem is not yet developed.
N2 - bestätigt werden. Wurde als Inhibitor Speichel eingesetzt, so ergab sich für den Speichel Neugeborener eine 4-Sfach stärkere Inhibition als für Erwachsenenspeichel Parallel dazu ergab die Untersuchung der Speichelproben für Neugeborene einen 4-Sfachen höheren. Die Adhäsion clonierter, Fluoresceinisothiocyanat (FITC)-markierter, S-Fimbrien tragender E. coli an menschliche Mundschleimhautzellen wurde untersucht. Die fluoreszenzmikroskopische Auswertung ergab, daß 75-95% der Schleimhautzellen Bakterien gebunden hatten. Die Spezifität der Bindung der Bakterien an Sialoglykoproteine konnte durch Inhibitionsexperimente mit Fetuin, saurem arGlykoprotein und N-acetyl-Neuraminsäure Gehalt an Gesamt-N-acetyl-Neuraminsäure. In Westerohlot Analysen konnten nur in Proben nativen Speichels Neugeborener mit Wheat Germ Agglutinin (WGA) reagierende Sialoglykoproteinbanden mit Molekülmassen > 200 kD identifiziert werden, die aufgrund ihres Molekulargewichtes und Färbeverhaltens der Klasse der Mucine zuzuordnen sind. Speichelmucine können einen wichtigen Abwehrmechanismus gegen Infektionen in einer Periode der kindlichen Entwicklung darstellen, in der das sekretorische IgA-System noch nicht voll entwickelt ist.
KW - Escherichia coli
KW - Speichel
KW - Neugeborenes
KW - Erwachsener
KW - Adhäsion
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86291
ER -
TY - JOUR
A1 - Parkkinen, Jaakko
A1 - Hacker, Jörg
A1 - Korhonen, Timo K.
T1 - Enhancement of tissue plasminogen activator-catalyzed plasminogen activation by Escherichia coli S fimbriae associated with neonatal septicaemia and meningitis.
N2 - The effect of Escherichia coli strains isolated from blood and cerebrospinal fluid of septic infants on plasminogen activation was studied. These strains typically carry a filamentous surface protein, S fimbria, that has formerly been shown to bind to endothelial cells and interact with plasminogen. The bacteria effectively promoted plasminogen activation by tissue plasminogen activator (t-PA) which was inhibited by e-aminocaproic acid. A recombinant strain expressing S fimbriae accelerated t-PAcatalyzed plasminogen activation to a similar extent as did the wild-type strains whereas the nonfimbriate recipient strain had no effect. After incubation with t-PA and plasminogen, the S-fimbriate strain displayed bacterium-bound plasmin activity whereas the nonfimbriate strain did not. Bacterium-associated plasmin generation was also observed with a strain expressing mutagenized S fimbriae that Iack the cell-binding subunit SfaS but not with a strain lacking the major subunit SfaA. Both t-PA and plasminogen bound to purified S fimbriae in a lysine-dependent manner and purified S fimbriae accelerated t-PA-catalyzed plasminogen activation. The results indicate that E. coli S fimbriae form a complex with t-PA and plasminogen which enhances the rate of plasminogen activation and generates bacterium-bound plasmin. This may promote bacterial invasion and persistence in tissues and contribute to the systemic activation of fibrinolysis in septicaemia.
KW - Escherichia coli
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-71566
ER -
TY - CHAP
A1 - Lutz, Werner K.
T1 - Dose-response relationships in chemical carcinogenesis: from DNA adducts to tumor incidence
N2 - Mechanistic possibilitles responsible for nonlinear shapes of the dose-response relationship in chemical carcinogenesis are discussed. (i) Induction and saturation of enzymatic activation and detoxification processes and of DNA repair affect the relationship between dose and steady-state DNA adduct Ievel; (ii) The fixation of DNA adducts in the form of mutations is accelerated by stimulation of the cell division, for Jnstance due to regenerative hyperplasia at cytotoxic dose Ievels; (iii) The rate of tumor formation results from a superposition of the rates of the individual steps. It can become exponential with dose if more than one step is accelerated by the DNA damage exerted by the genotoxic carcinogen. The strongly sigmoidal shapes often observed for dose-tumor incidence relationships in animal bioassays supports this analysis. A power of four for the dose in the su~linear part of the curve is the maximum observed (formaldehyde). In contrast to animal experiments, epidemiological data ln humans rarely show a slgnificant deviation from linearity. The discrepancy might be explained by the fact that a I arge nu mber of genes contribute to the overall sensitivity of an individual and to the respective heterogeneity within the human population. Mechanistic nonlinearities are flattened out in the presence of genetic and life-style factors which affect the sensitivity for the development of cancer. For a risk assessment, linear extrapolation from the high-dose lncidence to the spontaneaus rate can therefore be approprlate in a heterogeneous population even if the mechanism of action would result in a nonlinear shape of the dose-response curve in a homogeneaus population.
KW - aflatoxin B1
KW - 2-acetylaminofluorene
KW - DNA
KW - adduct
KW - covalent
KW - binding
KW - carcinogen
KW - dose
KW - extrapolation
KW - individual
KW - susceptibility
KW - heterogeneous population
KW - risk
KW - tumour
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-71625
ER -
TY - CHAP
A1 - Shephard, S. E.
A1 - Meier, I.
A1 - Lutz, Werner K.
T1 - Alkylating potency of nitrosated amino acids and peptides
N2 - Tbe alkylating potency of unstable N-nitrosamino acids and N-nitrosopeptides was investigated in vitro using 4-(para-nitrobenzyl)pyridine (NBP) as nucleophile. Of the amino acids, Met and those with an aromatic side chain were the most potent. The relative overall alkylating potency was 23:10:5:4:2:1: for Trp, Met, His, 1)rr, Phe and Gly, respectively. The homo-dipeptides were much more potent than the amino acids, with relative potencies of 400:110:100:8:3:1, for Trp-Trp, l)T-'I)T, Met-Met, Asp-Asp, Phe-Phe and Gly, respectively. In the one-phase reaction system (in which NBP is already present durlog the nitrosation reaction at acidic pH), all amino acids tested showed a second-order reaction for nitrite. In the two-phase system (in which NBP is added only after bringing the nitrosation reaction mixture to neutrality), all amino acids tested except one again showed a second-order reaction for nitrite (Phe, His, Asp and the dipeptide artiticial sweetener aspartame); only Met under these conditions bad a reaction order of one for nitrite. This could mean that nitrosation of the side chain of Metproduces a second N-nitroso product which is relatively stable in acid but reacts with NBP under neutral conditions. In the human stomach, this side-chain nitrosation might become more important than the reactions at the primary amino group, firstly because of the greater stability of the product(s) in acid and secondly because of the tirst-order reaction rate for nitrite. A decrease in nitrite concentration from the millimolar concentrations ofthe in-vitro assay to the micromolar concentrations in the stomach reduces the reaction rate by a factor of 1000 for the side-chain nitrosation, whereas a million-fold reduction will be observed for nitrosation of the amino group.
KW - Aminosäuren
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86320
ER -
TY - JOUR
A1 - Thiry, Marc
A1 - Scheer, Ulrich
A1 - Goessens, Guy
T1 - Localization of nucleolar chromatin by immunocytochemistry and in situ hybridization at the electron microscopic level
N2 - Nucleoli are the morphological expression of the activity of a defined set of chromosomal segments bearing rRNA genes. The topological distribution and composition of the intranucleolar chromatin as well as the definition of nucleolar structures in which enzymes of the rDNA transcription machinery reside have been investigated in mammalian cells by various immunogold labelling approaches at the ultrastructural level. The precise intranucleolar location of rRNA genes has been further specified by electron microscopic in situ hybridization with a non-autoradiographic procedure. Our results indicate that the fibrillar centers are the sole nucleolar structures where rDNA, core histones, RNA polymerase I and DNA to po isomerase I are located together. Taking into account the potential value and limitations of immunoelectron microscopic techniques, we propose that transcription of the rRNA genes takes place within the confines of the fibrillar centers, probably close to the boundary regions to the surrounding dense fibrillar component.
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39289
ER -
TY - JOUR
A1 - Näslund, Jan Carol
A1 - Schneider, Wolfgang
T1 - Longitudinal effects of verbal ability, memory capacity, and phonological awareness on reading performance
N2 - This study addresses the longitudinal relationship among verbal ability, memory capacity, phonological awareness, and reading performance. Data from 92 German children were used to explore the exact relation among these variables. Indicators of verbal ability, memory capacity, and phonological awareness were assessed in kindergarten and again after the first grade. The interrelationships among these factors, and the subsequent influence they have on decoding speed and reading comprehension during the second grade were examined via structural equation modefing procedures. Overall, the results of the longitudinal analyses show that the relationship of memory capacity and phonological awareness remains stable over time, and that memory capacity predicts performance on phonological awareness tasks in both kindergarten and second grade. Phonological awareness proved to be a significant predictor of decoding speed, which in turn considerably influenced reading comprehension.
KW - Lesefähigkeit
KW - Sprachfertigkeit
KW - Gedächtnisleistung
KW - Phonologische Bewusstheit
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86606
ER -
TY - JOUR
A1 - Pauli, Paul
A1 - Hartl, Lydia
A1 - Marquardt, Christian
A1 - Stalmann, Henrica
A1 - Strian, Friedrich
T1 - Heartbeat and arrhythmia perception in diabetic autonomic neuropathy
N2 - A comparative study of diabetics with autonomic neuropathy (N = 13) as against nonneuropathic diabetics (N = 16) and healthy control persons (N = 20) was carried out with respect 10 heart rate both at rest and under stress, frequency of cardiac arrhythmias in a 24-h ECG and accuracy of heartbeat and arrhythmia perception. In the subjects with diabetic autonomic neuropathy, the spontaneaus variability and stress-induced reactivity of the heart rate as weil as the number of tachycardic episodes were reduced, whereas the frequency of ventricular extrasystoles was somewhat increased. Impaired heartbeat perception and a complete Ioss of perception of arrhythmias as a consequence of neuropathic deafferentation could be demonstrated. Cardiac perception disordersalso playavital roJe in other clinical problems, e.g. silent myocardial infarction and Iack of awareness of hypoglycaemia in diabetes mellitus.
KW - Psychologie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-73599
ER -
TY - JOUR
A1 - Pauli, Paul
A1 - Marquardt, Christian
A1 - Hartl, Lydia
A1 - Nutzinger, Detlef O.
A1 - Hölzl, Rupert
A1 - Strian, Friedrich
T1 - Anxiety induced by cardiac perceptions in patients with panic attack: a field study
N2 - In panic disorder bodily sensations appear to play an important role as a trigger for anxiety. In our psychophysiological model of panic attacks we postulate the following vicious circle: individuals with panic attacks perceive even quite small increases in heart rate and interpret these changes as being catastrophic. This elicits anxiety and a further increase in heart rate. To evaluate this model we conducted a field study of 28 subjects with panic attacks and 20 healthy controls. A 24 hr ambulatory ECG was recorded and the subjects were instructed to report any cardiac perceptions during this period and to rate the anxiety elicited by these perceptions. The incidence of cardiac perceptions was about the same in both groups, but only subjects with panic attacks reported anxiety associated with such perceptions. Analysis of the ECGs revealed that in both groups heart rate accelerations preceded cardiac perceptions. Following cardiac perceptions, the healthy controls showed a heart rate deceleration, whereas the subjects with panic attacks had a further acceleration. This heart rate increase after cardiac perceptions was positively related to the level of anxiety elicited by the perceptions. These results provide clear evidence in support of the vicious circle model of panic attacks.
KW - Psychologie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61334
ER -
TY - JOUR
A1 - Schneider, Wolfgang
A1 - Sodian, Beate
T1 - A longitudinal study of young children's memory behavior and Performance in a sort-recall task
N2 - No abstract available
KW - Psychologie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62169
ER -
TY - JOUR
A1 - Bossert, Sabine
A1 - Laessle, Reinhold G.
A1 - Meiller, Caroline
A1 - Junker, Matthias
A1 - Ellgring, Johann Heinrich
A1 - Pirke, Karl-Martin
T1 - Visual palatability of food in patients with eating disorders and dieting women
N2 - The effects of 19 meals of different caloric content on slides on palatability and hypothetical duration of consumption were investigated in 7 patients with anorexia nervosa, 17 patients with bulimia nervosa at the beginning and after 8 weeks of hospital treatment. Nine healthy females served as controls. At the beginning of treatment, palatability of low caloric food was significantly higher and hypothetical duration of consumption of high caloric food was significantly longer in patients when compared to controls. After 8 weeks, in the patients palatability of low caloric food had decreased. Dislike for high caloric food remained stable in anorexics.
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42466
ER -
TY - JOUR
A1 - Schneider, Wolfgang
T1 - Domain-specific knowledge and memory Performance
N2 - No abstract available
KW - Psychologie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-50494
ER -