TY - JOUR A1 - Zentgraf, Hanswalter A1 - Trendelenburg, Michael F. A1 - Spring, Herbert A1 - Scheer, Ulrich A1 - Franke, Werner W. A1 - Müller, Ulrike A1 - Drury, Kenneth C. A1 - Rungger, Duri T1 - Mitochondrial DNA arranged into chromatin-like structures after injection into amphibian oocyte nuclei N2 - Purified mitochondrial DNA (mitDNA) from ovaries ofXenopus lae vis was injected into the nuclei (germinal vesicles) of large viteUogenic oocytes of the same organism and examined by electron microscopy ofthe spread nuclear contents. Normally located nuclei of untreated oocytes as weil as peripherally translocated nuclei of centrifuged oocytes were used. In addition, oocyte nuclei isolated and incubated under liquid paraffin oil were injected with DNA. The integrity oftranscriptional structures of endogenous chromosomal (Iampbrush chromosomes) and extrachromosomal (nucleoli) genes of the injected nuclei was demonstrated. Microinjected mitDN A was identified as circles of chromatin exhibiting polynucleosome-like organization and a me an contour length of 2.6 J.Lm, corresponding to a compaction ratio of the mitDN A of about 2 : I. This DNA packing ratio is similar to that observed after preparation of various kinds of native chromatin in low salt buffers. The chromatin circles formed from injected mitDNA only very rarely exhibited lateral fibrils suggestive of transcriptional activity. These results suggest that purified mitDNA can be transformed to normally structured chromatin when exposed to oocyte nuclear contents but is rarely , if at all , transcribed in this form and in this environment. Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33174 ER - TY - JOUR A1 - Weinert, Franz E. A1 - Treiber, Bernhard A1 - Schneider, Wolfgang T1 - Educational psychology N2 - This is a report on the more recent developments and the present state of research into educational psychology in German speaking countries. Particular emphasis is given to research on: parental upbringing and its effects on child development; the examination of socialization effects within and across different scbool systems; studies on teaching-leaming processes and on social interaction in the classroom; the systematic promotion of the development of cognitive abilities and motives in students; and, finally, the design of improved instruments in methods of describing, explaining and predicting school success. Subsequently, the report will look into problems in tbe practical application of research findings in educational psychology. Finally, there follows a sbort discussion of various metatheoretical positions in educational psycbology in German speaking countries and their possible effects on the future development of the field. KW - Pädagogische Psychologie Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-87234 ER - TY - CHAP A1 - Viviani, A. A1 - Lutz, Werner K. T1 - Modulation of the in vivo covalent binding of the carcinogen benzo(a)pyrene to rat liver DNA by selective induction of microsomal and nuclear aryl hydrocarbon hydroxylase activity N2 - The influence of microsomal (mAHH) and nuclear (nAHH) aryl hydrocarbon hydroxylase activity on the covalent binding of t:titiated benzo(a)pyrene to rat liver DNA was evaluated in vivo. Induction ofmAHH was obtained after phenobarbitone treatment (180% of control), which increased DNA binding to 210%, but left the nAHH unchanged. mAHH and nAHH were slightly indilced with dieldrin (130% and 120%), but the binding remairred unchanged. The increasing effect of mAHlt as weil as the possibly decreasing effect of nAHH induction on the binding became obvious when the data of 11 individual rats were used to solve the equation Binding = aX(mAHH) + bX(nAHH) + c. Multiple linear regression analysis resulted in positive values for a and c, a negative value for b, and a multiple correlation coefficient R = 0.82. An influence of other enzymes involved in the metabolism of benzo(a)pyrene cannot be excluded. The Study shows clearly that the binding of a foreign compound to DNA in vivo is not only dependent on microsomal enzyme activities but also on nuclear activities even if the latter are considerably lower than those of mic'rosomes. KW - DNA KW - Benzo(a)pyrene KW - DNA-Binding KW - Carcinogen KW - Enzyme KW - Induction KW - Aryl Hydrocarbon Hydroxylase KW - Rats KW - Phenobarbitone KW - Dieldrin Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-80132 ER - TY - JOUR A1 - Ulrichs, Karin A1 - Kuhlencordt, KM A1 - Müller-Ruchholtz, W. T1 - Plating inhibition assay (PIA): a new test for cell mediated cytotoxicity N2 - No abstract available Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45443 ER - TY - JOUR A1 - Tzagoloff, A. A1 - Macino, G. A1 - Sebald, Walter T1 - Mitochondrial genes and translation products N2 - No abstract available KW - Biochemie Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47408 ER - TY - JOUR A1 - Sebald, Walter A1 - Wild, G. T1 - Mitochondrial ATPase complex from Neurospora crassa N2 - The A TPase eomplex has been isolated from mitoehondria of N eurospora crassa by immunologieal teehniques. The protein ean be obtained rapidly and qua ntitatively in high purity by miero- or large-seale immunopreeipitation. Immunopreeipitation has been applied to labeled and doubly labeled mitoehondrial proteins in order to investigate the number and moleeular weights of subunit polypeptides , the site of synthesis of subunit polypeptides, and the dieycIohexyIcarbodiimide-binding protein . The A TPase complex obtained by large-seale immunopreeipitation has been used as starting ma terial for the isolation of hydrophobie polypeptides. KW - Biochemie Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-82065 ER - TY - JOUR A1 - Sebald, Walter A1 - Werner, S A1 - Weiss, H T1 - Biogenesis of mitochondrial membrane proteins in Neurospora crassa N2 - no abstract available KW - Biochemie KW - Neurospora crassa Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-82055 ER - TY - JOUR A1 - Sebald, Walter A1 - Wachter, E. A1 - Tzagoloff, A. T1 - Identification of amino acid substitutions in the dicyclohexylcarbodiimide-binding subunit of the mitochondrial ATPase complex from oligomycin-resistant mutants of Saccharomyces cerevisiae N2 - No abstract available KW - Biochemie Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62770 ER - TY - JOUR A1 - Sebald, Walter A1 - Neupert, W. A1 - Weiss, H. T1 - Preparation of Neurospora crassa mitochondria N2 - The fungus Neurospora crassa represents a eukaryotic cell with high biosynthetic activities. Cell mass doubles in 2-4 hr during expone ntial growth , even in simple salt media with sucrose as the sole carbon source. The microorgani sm forms a mycelium of long hyphae durlng vegetative growth . The mitochondria can be isolated under relatively gentle condi tions since a few breaks in the threadlike hyphae are sufficient to cause the outflow of the organelles. This article describes two methods for the physical disruption of the hyphae : (I) The cell s are opened in a grind mill between two rotating corundum di sks. This is a continuous and fast procedure and allows large- and small-scale preparations of mitochondria. (2) Hyphae are ground with sand in a mortar and pestle. This procedure can be applied to microscale preparations of mitochondria starting with minute amounts of cells. Other procedures for the isolation of Neurospora mitochondria after the physical di sruption or the enzymatic degradation of the cell wall have been described elsewhere KW - Biochemie Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-82070 ER - TY - JOUR A1 - Sebald, Walter A1 - Graf, T. A1 - Lukins, H. B. T1 - The dicyclohexylcarbodiimide-binding protein of the mitochondrial ATPase complex from Neurospora crassa and Saccharomyces cerevisiae. Identification and isolation N2 - Incubation of mitochondria from Neuraspara crassa and Saccharomyces cerevisiae with the radioactive ATPase inhibitor [14C]dicyclohexylcarbodiimide results in the irreversible and rather specific labelling of a low-molecular-weight polypeptide. This dicyclohexylcarbodiimide-binding protein is identical with the smallest subunit (Mr 8000) of the mitochondrial ATPase complex, and it occurs as oligomer, probably as hexamer, in the enzyme protein. The dicyclohexylcarbodiimide-binding protein is extracted from whole mitochondria with neutral chloroformjmethanol both in the free and in the inhibitor-modified form. In Neuraspara and yeast, this extraction is highly selective and the protein is obtained in homogeneaus form when the mitochondria have been prewashed with certain organic solvents. The bound dicyclohexylcarbodiimide Iabel is enriched in the purified protein up to 50-fold compared to whole mitochondria. Based on the amino acid analysis, the dicyclohexylcarbodiimide-binding protein from Neurospora and yeast consists of at least 81 and 76 residues, respectively. The content of hydrophobic residues is extremely high. Histidine and tryptophan are absent. The N-terminal ~mino acid is tyrosine in Neuraspara and formylmethionine in yeast. KW - Biochemie Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62792 ER - TY - CHAP A1 - Scheer, Ulrich A1 - Spring, Herbert A1 - Trendelenburg, Michael F. T1 - Organization of transcriptionally active chromatin in lampbrush chromosome loops N2 - No abstract available Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39293 ER - TY - JOUR A1 - Scheer, Ulrich A1 - Sommerville, John A1 - Bustin, M. T1 - Injected histone antibodies interfere with transcription of lampbrush chromosome loops in oocytes of Pleurodeles N2 - Antibodies to calf thymus histone H2B were purified by chromatography on DEAE-cellulose and injected into oocyte nuclei of Pleurodeles waltlii. As shown by indirect immunofluorescence these antibodies cross-reacted strongly with corresponding histones associated with lampbrush chromosomes. Shortly after injection the lateral loops of the chromosomes retracted into the chromomeres and by 3 h postinjection the 'lampbrush' appearance was completely lost and the chromosomes appeared in light-microscopic preparations as rod-like structures consisting of 10ngitudina11y coalesced chromomeres. In control oocytes injected with non-immune immunoglobulins or antibodies against a ubiquitous transcript-associated protein no morphological alterations of the lampbrush chromosomes could be observed. Electron microscopic spreads of chromosomes prepared at various times after injection of anti-H2B revealed a progressive loss of transcriptional complexes from the loop axes. Finally, higher-order chromatin configurations, like supranuc1eosomal globules (' superbeads ') or cable-like chromatin strands 50- 60 nm thick predominated, indicating complete transcriptional inactivation of a11 chromosomal regions. The results indicate that H2B antibodies react specifically with his tones associated with the transcribed DNA of lateral loops in their native state. The resulting antigenantibody complexes seem to inhibit progression of the R A polymerases along the template, thus causing the premature release of transcripts, a process analogous to the stripping effect of actinomycin D. The demonstration of histones associated with heavily transcribed regions, which are not compacted into nucleosomes but largely extended, supports the current concept that unfolding of nucleosomes to a110w transcription of the DNA does not involve dissociation of histones. In contrast, amplified ribosomal RNA genes are unaffected by injected HzB antibodies. This does not necessarily indicate absence of his tones from nucleolar chromatin, since we do not know whether it is accessible in vivo to antibodies or whether the histone antigenie determinants are masked by the presence of other proteins. The technique of injecting specific antibodies should be widely applicable when analysing the in vivo distribution of chromosomal components at the electron-microscopic level and when studying complex metabolie processes, like the cleavage and modification of RNA, by selective inhibition of defined enzymic steps. Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33166 ER - TY - JOUR A1 - Michel, R. A1 - Wachter, E. A1 - Sebald, Walter T1 - Synthesis of a larger precursor for the proteolipid subunit of the mitochondrial ATPase complex of Neurospora crassa in a cell-free wheat germ system N2 - No abstract available KW - Biochemie Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62789 ER - TY - JOUR A1 - Meyer, Manfred K. A1 - Schartl, Manfred T1 - Eine neue Xiphophorus-Art aus Vera Cruz, Mexiko : (Pisces: Poeciliidae) N2 - Xiphophorus andersi n. sp. from the Rio Atoyac, Vera Cruz, Mexico is described: lang head, moderately slender body, large dark black spar at the basis of the anal fin; adult male with short sword-like caudal appendage; rip of ray 5a of gonopodium without a developed claw. Xiphophorus andersi n. sp. differs by the combination of distinct characters from all the other species of the genus known so far. The new species shows features of both the so-called platyfish species group and the so-called swordtail species group. KW - Schwertkärpfling KW - Veracruz Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-87124 ER - TY - JOUR A1 - Lutz, Werner K. T1 - In vivo covalent binding of organic chemicals to DNA as a quantitative indicator in the process of chemical carcinogenesis N2 - The covalent binding of chemical carcinogens to DNA of mammalian organs is expressed per unit dose, and a 'Covalent-Binding Index', CBI, is defined. CBI for various carcinogens span over 6 orders of magnitude. A similar range is observed for the carcinogenic potency in long-term bioassays on carcinogenicity. For the assessment of a risk from exposure to a carcinogen, the total DN A darnage can be estimated if the actual dose is also accounted for. A detailed description is given for planning and performing a DNA-binding assay. A complete literature survey on DNA binding in vivo (83 compounds) is given with a calculation of CBI, where possible, 153 compounds are listed where a covalent binding to any biological macromolecule has been shown in vivo or in vitro. Recent, so far unpublished findings with aflatoxin Mh macromolecule- bound aflatoxin Bh ·diethylstilbestrol, and 1,2-epithiobutyronitrile are included. A comparison of CBI for rat-liver DNA with hepatocarcinogenic potency reveals a surprisingly good quantitative correlation. Refinements for a DN A-binding assay are proposed. Possibilities and Iimitations in the use of D NA binding in chemical carcinogenesis are discussed extensively. KW - Toxikologie Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61122 ER - TY - JOUR A1 - Kutateladze, T. V. A1 - Axelrod, V. D. A1 - Gorboulev, Valentin G. A1 - Belzhelarskaya, S. N. A1 - Vartikyan, R. V. T1 - New procedure of high-voltage electrophoresis in polyacrylamide gel and its application to the sequencing of nucleic acids N2 - Fractionation of nucleic acids and their fragments with polyacrylamide gel has been widely applied in sequencing of nucleic acids. Although the conditions of electrophoresis for this purpose have previously been suggested. we have found that polyacrylamide gel electrophoresis at 5000 V (100 V/cm) is possible and effective. An apparatus consisting of a horizontal thermostated plate is used to remove the heat which was formed during the electrophoretic process. The techniques for loading samples on the horizontal thin gel and the procedure for high-voltage gel electrophoresis are described and illustrated by the fractionation of the spleen phosphodiesterase partial digest of tRNA¥~1 as well as by the RNA synthesis by RNA polymerase from E. coli with poly[d(A- T)j as template in the presence of "terminator," 3'-O-methyluridine 5'-triphosphate. This same technique was used for electrophoresis of oligonucleotides on acetylcellulose and was incorporated into a two-dimensional system which was demonstrated by fingerprinting of the guanylo-RNase digest of tRNAT'P from baker's yeast. In the third part of the article a simple technique for the electric trapping of nucleic acids or their fragments from a slab gel on a DEAE-paper sheet is presented. Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-46927 ER - TY - JOUR A1 - Karppanen, H. A1 - Sirén, Anna-Leena A1 - Eskeli-Kaivosoja, Alice T1 - Central cardiovascular and thermal effects of Prostaglandin F2α in rats N2 - Administration of PGF 2IX (0.2-6.4 J.lg) into the lateral cerebral ventricle (i.c.v.) induced dosedependent increases in blood pressure , heart rate and body temperature in urethane-anaesthetised rats, but had no effect on these parameters when the same dose range was administered intravenously. Peripheral pretreatment with sodium meclofenamate (50 mg/kg s.c.) sltifted all the dose-response curves for PGF 2IX (i.c.v.) to the left, but indomethacin (50 mg/kg s.c.) did not significantly affect those changes. Central pretreatment with sodiurn meclofenamate or indomethacin (1.25 mg per rat i.c.v.) failed to modify significantly the effects of centrally administered PGF 2IX' The results support previous suggestions that PGF 2IX may participate in the central control of the cardiovascular and thermoregulatory systems, and also suggest that there may be differences in the sites and/or modes of action between sodiurn meclofenamate and indomethacin. KW - Prostaglandine Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47955 ER - TY - JOUR A1 - Jaggi, W. A1 - Lutz, Werner K. A1 - Schlatter, C. T1 - Comparative studies on the covalent binding of the carcinogen benzo(a)pyrene to DNA in various model systems N2 - The covalent binding of tritiated benzo(a)pyrene (BP) to DNA has been determined in rat liver in vivo, in rat liver perfused in situ, after incubation of BP with liver single cells, with liver homogenate, with liver microsomes and DNA, with fibroblasts from a rat granulorna pouch, and with · 2 cell lines. Li ver single cells were found to be a valuable compromise between the rnost sensitive system (microsomal incubation of BP with DNA) and the biologically most relevant system (in vivo ). KW - Toxikologie Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61131 ER - TY - JOUR A1 - Heinsen, Helmut T1 - Lipofuscin in the cerebellar cortex of albino rats: an electron microscopic study N2 - The ultrastructure of autofluorescent, PAS-positive lipofuscin in Purkinje, granule, Golgi epithelial, basket and stellate, microglial and perivascular cells in the cerebellar cortex of senescent rats is described. The membrane- bounded pigment is composed ofthree elements: 1) electron-lucent homogeneaus droplets, 2) a granular matrix and 3) intensely osmiophilic patches. The proportians ofthese three components vary between cell types and one can grossly differentiate a neuronal and a gliallipofuscin. The lipofuscin granules of stellate and perivscular cells are different from lipofuscin of other cerebellar neurons and glia. lt can be concluded from these morphological observations that each cerebellar cell type has its distinct lipofuscin. KW - Medizin KW - Lipofuscin KW - Cerebellar cortex KW - Ultrastructure KW - Senescent rat Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59891 ER - TY - CHAP A1 - Franke, Werner W. A1 - Scheer, Ulrich A1 - Spring, Herbert A1 - Trendelenburg, Michael F. A1 - Zentgraf, Hanswalter T1 - Organization of nucleolar chromatin N2 - No abstract available Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39410 ER -