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- Cultural Animal Studies, Band 3 (24)
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Sonstige beteiligte Institutionen
- VolkswagenStiftung (24)
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ResearcherID
- B-1911-2015 (1)
- B-4606-2017 (1)
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- D-3057-2014 (1)
- I-5818-2014 (1)
- J-8841-2015 (1)
- M-1240-2017 (1)
- N-2030-2015 (1)
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.
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.
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.
The determination of a covalent binding of radioactive chemieals to DNA in intact mammalian organisms is proposedas a short-term test for carcinogenicity. The effectiveness of covalent binding to rat liver DNA correlates well with the hepatocarcinogenicity known from long-term bioassays. The binding indices range over more than five orders of rriagnitude between the strongest hepatocarcinogen aflatoxin B 1 and the limit of detection of a binding with 100 f-LCi 14C-labelled chemical. The order of magnitude of binding is therefore a surprisingly good quantitative measure for carcinogenicity. The pattern of DNA binding sites is important especially for small alkylating agents where the determination of total binding might indicate a higher carcinogenic potency than is actually observed.
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.
no abstract available
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.
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
No abstract available.
No abstract available.
No abstract available
Am Konzept der Axialsymmetrie multivariater Daten wird eine Methode entwickelt, mit der statistisch Cluster aus gleich interkorrelierenden Variablen gebildet werden können. Es wird eine heuristische Vorgehensweise empfohlen, die nicht wie die übliche deskriptive Clusteranalyse willkürliche Entscheidungen über Abbruchkriterien u.ä. verlangt. Die vorgeschlagene Methode ist insbesondere zur mediandichotomierte kontinuierliche Variablen geeignet. Werden echte Alternativdaten verwendet, resultieren Cluster, die zusätzlich zur gleichen Interkorrelation Variablen mit gleicher Schwierigkeit aufweisen. Das Vorgehen wird an einem Beispiel illustriert.
Educational psychology
(1979)
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.
No abstract available
Drei Methoden zur Bestimmung zweiseitiger Überschreitungswahrscheinlichkeiten bei der exakten Prüfung von Vierfeldertafeln nach FISCHER-YATES werden diskutiert. An einem Beispiel wird aufgezeigt, daß diese Methoden zu verschiedenen Signifikanzentscheidungen führen können. Es werden Möglichkeiten aufgezeigt, wie diese Schwierigkeiten in der Praxis umgangen werden können.
Ein neues Lamaštu-Amulett
(1979)
No abstract available
No abstract available
No abstract available
The amino acid sequence of the proteolipid subunit of the A TP synthase was analyzed in six mutant strains from Escherichia coli K 12, selected for their increased resistance towards the inhibitor N,N'-dicyclohexylcarbodiimide. All six inhibitor-resistant mutants were found to be altered at the same position of the proteolipid, namely at the isoleucine at residue 28. Two substitutions could be identified. In type I this residue was substituted by a valine resulting in a moderate decrease in sensitivity to dicyclohexylcarbodiimide. Type II contained a threonine residue at this position. Here a strong resistance was observed. These two amino acid substitutions did not influence functional properties of the ATPase complex. ATPase as well as A TP-dependent proton-translocating activities of mutant membranes were indistinguishable from the wild type. At elevated concentrations, dicyclohexylcarbodiimide still bound specifically to the aspartic acid at residue 61 of the mutant proteolipid as in the wild type, and thereby inhibited the activity of the ATPase complex. It is suggested that the residue 28 substituted in the resistant mutants interacts with dicyclohexylcarbodiimide during the reactions leading to the covalent attachment of the inhibitor to the aspartic acid at residue 61. This could indicate that these two residues are in close vicinity and would thus provide a first hint on the functional conformation of the proteolipid. Its polypeptide chain would have to fold back to bring together these two residues separated by a segment of 32 residues.
NH4CuS4 was prepared according to syntheses reported in the literature. Orthorhombic crystals could be grown (P21 21 21 , a = 5.249(1), b = 8.444(2), c = 12.782(2) A, Z = 4), the structure of which was solved from X-ray diffractometer data. (R = 0.031 for 767 obs. reflections). In the solid state (CuS4)- chelate rings are linked via additional Cu-S-bonds to form one-dimensional polymerie anions.
No abstract available
Children's information processing of risky choice alternatives was investigated in two studies without using verbal reports. In Study 1, the ability to integrate the probabilities and the payoffs of simple bets was examined using the rating scale methodology. Children's choices among three of those simple bets were recorded also. By cross-classifying the children's choice and rating behavior it was shown that a three-stage developmental hypothesis of decision making is not sufficient. A four-stage hypothesis is proposed. In Study 2, the influence of enlarging the presented number of alternatives from two to three and the influence of the similarity of the alternatives on children's choice probabilities was examined with those bets. Children's choice behavior was probabilistic and was influenced only by enlarging the presented number of alternatives. These results suggest that a Bayesian approach, based on two probabilistic choice models, should not be applied in order to analyze children's choice behavior. The functional measurement approach is, as was demonstrated in Study 1, a powerful implement to further the understanding of the development of decision making.
When reovirus-infected Hela cells are incubated at 43°C virus-specific messenger RNA is released ~rom the polysomes. It accumulates free in the cytoplasm as messenger ribonucleoprotem partIcles (mRNPs). The:e part~cles have a sedimentati~n rate of about 50S and a buoyant densIty m CsCI of 1.42 g/cm . ReovIrus mRNPs contam, beSIdes all three size classes of reovirus messenger RNA, the same spectrum of proteins found in the polysomal mRNPs from uninfected cells, plus t~o addi~ional pr?teins with molecular masses of 7000~ d and 110000 d, respectively. Electron mIcroscoPIc exammatlOn of the reovIrus mRNP fractIOn reveals specific Y-shaped structures wIth a total mean length ofO.5Ilm.
[\(^{14}\)C] Aflatoxin B\(_1\) (AFB\(_1\)) was isolated from cultures of Aspergillus parasiticus grown on [1-\(^{114}\)C] sodium acetate. Covalent binding of AFB1 to liver DNA of rat and mouse was determined 6-8 h afteroral administration. The effectiveness of covalent binding, expressedas DNA binding per dose in the units of a 'Covalent Binding Index' (CBI), (\(\mu\)mol aflatoxin/mol DNA nucleotides)/(mmol aflatoxin/kg animal), was found to be 10 400 for rats and 240 for mice. These CBI partly explain the different susceptibility of the two species for the incidence of hepatic tumors. The corresponding values for pig liver DN A, 24 and 48 h after oral administration, were found to be as high as 19 100 and 13 300. DNA-binding has not so far been reported for this species although it could represent an appropriate animal model for studies where a human-like gastrointestinal tract physiology is desirable. Aflatoxin M \(_1\) ( AFM\(_1\)) is a metabolite found in the milk of cows that have been fed AFB\(_1\)-contaminated diet. [\(^{14}\)C] AFM\(_1\) was also found to be produced by cultures of A. parasiticus giving a yield of about 0.3% of the total aflatoxins. A test for covalent binding to rat liver DN A revealed a CBI of 2100 shoWing that AFM\(_1\) must also be regarded as a strong hepatocarcinogen. It is concluded that AFB\(_1\) contaminations should be avoided in dairy feed.
In vivo covalent binding of aflatoxin metabolites isolated from animal tissue to rat-liver DNA
(1980)
Ring-labelled [\(^{14}\)C)aflatoxin B\(_1\) (AFB\(_1\)), prepared by biosynthesis. or generally labelled [\(^3\)H]AFB\(_1\) was administered by oral gavage to young adult male rats. After 6 hr. the liver was removed and two fractions were isolated, namely macromolecules, which contamed about 3 % of the initial dose of AFB\(_1\) radioactivity. and water-soluble, low-molecular aftatoxin conjugates containing about0·2% of the administered radioactivity. These two fractions were administered orally to other rats in order to determine the potential of radioactive aftatoxin residues for covalent binding to DNA. Such binding can be used as an indicator for carcinogenic potency. Liver DNA was isolated 9-12 hr after admmistration of the aflatoxin derivatives and in no case was any radioactivity detected on the DNA. It can be deduced on the basis of the limit of detection of radioactivity on the DNA, that macromolecule bound AFB\(_1\) derivatives are at least 4000 times less active than AFB\(_1\) with respect to covalent binding to rat-liver DNA. and that the water-soluble conjugates are at least 100 times less potent than AFB, itself. It is concluded that the carcinogenic risk for humans who consume liver or meat. containing such aflatoxin residues is negligible when compared with the risk from intake of aftatoxins in other food items.
Groups of four adult male rats [ZUR:SIV -Z] were pretreated with corn oil (control; 2 ml/kg/day i. p. for 3 days), trans-stilbene-oxide (SO; 200 mg/kg/day i. p. for 2 days), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; 10 \(\mu\)g/kg i. p. once, 4 days before killing), phenobarbital (PB; 1 gjliter in the drinking water for 8 days), and dieldrin (20 mg/kg/day i. p. for 3 or 9 days). They received an injection of [G-\(^3\)H]benzo(a)pyrene (BaP, 31 \(\mu\)g/kg, 7.4. 10\(^9\) dpm/kg; i. v.) 16 h before killing. In the liver of each rat, five enzymatic activities and the covalent binding of BaP to DNA have been determined. The rnicrosomal aryl hydrocarbon monooxygenase activity (AHM) ranged frorn 75% of control (SO) to 356% (TCDD), the nuclear AHM from 63% (SO) to 333% (TCDD). Microsomal epoxide hydrolase activity (EH) was induced up to 238% (PB), nuclear EH ranged from 86% (TCDD) to 218% (PB). A different extent of induction was observed in the two compartments. Highest induction of glutathione S-epoxide transferase activity (GST) was found with PB (202%). The DNA binding of BaP was modulated within 79% (dieldrin, 9 days) and 238% of control (TCDD). An enzyme digest of control DNA was analysed by Sephadex LH-20 chromatography. Multiple linear regression analysis with all data expressedas o/o of control yielded the following equation: DNA Binding = 1.49 · Microsomal AHM- 1.07 · Nuclear AHM+ 0.33 · Microsomal EH- 0.52 · N uclear EH+ 0.11 · Cytoplasmic GST + 58.2. From this analysis it is concluded that (1) AHM located in the endoplasmic reticulum is most important in the formation of DNA-binding metabolites, (2) EH in the same compar.tment is not determinative in thls respect nor has it a protective effect, (3) both membrane-bound enzyme activities located in the nucleus may inactivate potential ultimate carcinogens, and ( 4) cytoplasmic GST probably cannot reduce DNA binding due to its subcellular localization.
Sila-Chlorphencyclan (8b), ein Sila-Analogon des Chlorphencyclans (8a), die Derivate 7 und 9, deren Ammoniumsalze 11, 12, 13 und 14b, das Hydrolyseprodukt 10 sowie die Vorstufen 3-6 wurden erstmalig dargestellt. Die neuen Verbindungen wurden in ihren chemischen und physikalischen Eigenschaften charakterisiert, ihre Struktur wurde sichergestellt. Chlorphencyclan, Sila-Chlorphencyclan und einige seiner Derivate wurden vergleichend pharmakologisch und toxikologisch untersucht.
Sila-Analogon des Rythmols
(1980)
Sila-Rythmol (llb), ein Sila-Analogon des Antiarrhythmieums Rythmol (lla), wurde erstmalig dargestellt. llb sowie die Vorstufen und Nebenprodukte 4, 5, 6, 7, 9b und lOb wurden in ihren physikalischen und chemischen Eigenschaften charakterisiert und in ihrer Struktur sichergestellt. Die pharmakologischen und toxikologischen Eigenschaften der Analoga lla und llb wurden vergleichend untersucht.
Sila-Pridinol (2 b), ein Sila-Analogon des Anticholinergicums Pridinol (2a), wurde auf zwei verschiedenen Wegen dargestellt. Die Kristall- und Molekülstrukturen von 2 a und 2 b wurden röntgenstrukturanalytisch bestimmt. 2a bildet im festen Zustand intramolekulare Wasserstoffbrückenbindungen aus, während sich in kristallinem 2 b zentrosymmetrische, durch intermolekulare H-Brückenbindungen verknüpfte cyclische Dimere finden. IR- und \8^1\)H-NMR-spektroskopische sowie kryoskopische Untersuchungen ergaben Informationen über die Strukturen von 2a und 2 b in verschiedenen Lösungsmitteln. - Die pharmakologischen und toxikologischen Eigen" schaften von 2a und 2b wurden unter dem Gesichtspunkt bekannter Struktur-Wirkungs-Beziehungen vergleichend untersucht. 2 b erwies sich als ein etwa fünfmal so starkes Anticholincrgicum wie 2a.
Sila-Tiemoniumiodid (16b), ein Sila-Analogon des Anticholinergicums Tiemoniumiodid (16a), und das Sila-Analogon 14b der entsprechenden Tiemonium-Base 14a wurden erstmalig synthetisiert.14b und 16b sowie die Vorstufen 10-13 und 15 wurden in ihren physikalischen und chemischen Eigenschaften charakterisiert und in ihrer Struktur durch Elementaranalysen sowie \(^1\)H-NMR- und Massenspektren sichergestellt. Die spasmolytischen Eigenschaften der Paare 14a/14b und 16a/16b wurden am isolierten Meerschweinchendarm vergleichend untersucht.
Die potentiell curarewirksamen Silicium-Verbindungen Sa, Sc, Sd, Sg, Sh und 9a-9d wurden dargestellt. \(^1\)H-NMR-spektroskopische Untersuchungen ergaben Informationen über die Konformationen von 5 a- Sc in Lösung. Die Kristall- und Molekülstruktur von 5 c wurde röntgenstrukturanalytisch bestimmt. Die muskelrelaxierenden Eigenschaften von S a- 5 h und 9 a-9 d wurden vergleichend an der Maus (i.v., LD50-Werte) untersucht. Die ermittelten Struktur-WirkungsBeziehungen werden in Hinblick auf die unterschiedlichen kovalenten Radien des Kohlenstoffund Siliciumatoms und die hieraus resultierenden N ... N-Abstände diskutiert.
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Jahresbericht 1979
(1980)
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Häufig tritt in der psychologischen und psychiatrischen Forschung die Frage nach dem Zusammenhang zwischen zwei oder mehreren Zeitreihen auf. übliche Kovariationsmaße versagen dabei vor allem deshalb, weil sie nicht inferentiell ausgewertet werden können. An einem Beispiel aus der Pharmakopsychologie wird ein auf Pfanzagl (1963) zurückgehendes Verfahren vorgeschlagen, das es erlaubt, voraussetzungsfrei den Zusammenhang zwischen autokorrelierten Meßwertreihen zu prüfen. Als Unabhängigkeit zweier Zeitreihen wird definiert, daß zwischen ihnen bei Erhaltung der Autokorrelation kein höherer Zusammenhang besteht als nach dem Zufall zu erwarten.
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Der Zweikernkomplex C\(_5\)H\(_5\)(PMe\(_3\))Co(\(\mu\)-CO)\(_2\)Mn(CO)C\(_5\)H\(_4\)Me (8) reagiert mit stöchiometrischen Mengen S\(_8\) in praktisch quantitativer Ausbeute zu C\(_5\)H\(_5\)(PMe\(_3\))CoS\(_5\) (4). Der Koba.ltapentathia-Heterocyclus 4 ist ebenfalls aus C\(_5\)H\(_5\)(PMe\(_3\))Co(h\(^2\)-CS\(_2\)) (5) und S\(_8\) zugänglich. 4 kristallisiert monoklin mit den Gitterkonstanten a = 8,467(3) A, b = 12,128(4) A, c = 14,210(4) A und \(\beta\) = 102,20(2)°_ Die Sesselform des sechsgliedrigen CoS\(_5\)-Rings entspricht derjenigen in den bekannten Verbindungen (C\(_5\)H\(_5\))\(_2\)TiS\(_5\) und (C\(_5\)H\(_5\))\(_2\)VS\(_5\) , wobei in 4 der Cyclopentadienylligand die axiale und die Trimethylphosphingruppe die ä.quatoriale Position einnehmen.
CsCu\(_4\)S\(_3\) und CsCu\(_3\)S\(_2\) : Sulfide mit tetraedrisch und linear koordiniertem Kupfer
(1980)
No abstract available
The assembly of DNA into nucleosomal and supranucleosomal chromatin structures has been studied (i) by injection of circular DNA molecules (plasmids) into nuclei of Pleurodeles waltlii oocytes; and (ii) by in vitro incubation of plasmid molecules with the supernatant fraction from oocyte nuclei of Pleurodeles and Xenopus laevis, followed by purification of nucleoprotein structures formed with sucrose gradient centrifugation. [n both types of experiments , spread preparations of the newly assembled and transcriptionally inactive chromatin , examined by electron microscopy , show dense globular higher order (supranucleosomal) packing forms. Under partially relaxing (low salt) preparation conditions granular chromatin subunits of about 30 nm diameter can be seen either as widely spaced particles or in closely packed aggregates. The transcriptionally inactive endogenous chromatin of chromomeres of lampbrush chromosomes is arranged in similar higher order chromatin units. A correlation is found between the sizes of the DN A molecule probes used and the numbers of nucleosomes and higher order globules in the assembled chromatin structures. After prolonged dispersion in low salt buffers , these globular chromatin units unfold into chains of7-12 nucleosomes. The results support the concept that chromatin is arranged , under physiological ion concentrations as they are present in the nucleus , in supranucleosomal units of globular morphology.
In the present secondary analysis the results of studies by Simons et al. (1975) and Schwarzer (1979) were critically reanalyzed. The central point of the reanalysis concerned the test of the causal models used, especially the question, if the technique of path analysis was correctly applied. Whereas some modifications seemed necessary in both srudies, there was no reason to question their main results.
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List Sprachbuch 5
(1980)
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Transcribed nucleolar chomatin, including the spacer regions interspersed between the rRNA genes, is different from the bulk of nontranscribed chromatin in that the DNA of these regions appears to be in an extended (B) conformation when examined by electron microscopy. The possibility that this may reflect artificial unfolding of nucleosomes during incubation in very low salt buffers as routinely used in such spread preparations has been examined by studying the influence of various ion concentrations on nucleolar chromatin structure. Amplified nucleolar chromatin of amphibian oocytes (Xenopus laevis, Pleurodeles waltlii, Triturus cristatus) was spread in various concentrations of NaCl (range 0 to 20 mM). Below 1 mM salt spacer chromatin frequently revealed a variable number of irregularly shaped beads, whereas above this concentration the chromatin axis appeared uniformly smooth. At all salt concentrations studied, however, the length distribution of spacer and gene regions was identical. Preparations fixed with glutaraldehyde instead of formaldehyde, or unftxed preparations, were indistinguishable in this respect. The observations indicate that (i) rDNA spacer regions are not compacted into nucleosomal particles and into supranucleosomal structures when visualized at chromatin stabilizing salt concentrations (e.g., 20 mM NaCl), and (ii) spacer DNA is covered by a uniform layer of proteins of unknown nature which, at very low salt concentrations (below 1 mM NaCl), can artificially give rise to the appearance of small granular particles of approximately nucleosome-like sizes. These particles, however, are different from nucleosomes in that they do not foreshorten the associated spacer DNA. The data support the concept of an altered nucleohistone conformation not only in transcribed chromatin but also in the vicinity of transcriptional events.
b-Type cytochromes
(1980)
T~e N,N'-dicrclohexylcarbodiimide-binding proteolipid subumt of the mitochondrial adenosinetriphosphatases (ATP phosphohydrolase, EC 3.6.1.3) of Neurosporacrassa and Saccharomyces cerevisiae were purified from mitochondria incubated with the radioactively labeled inhibitor. The specifically labeled subunit was cleaved with cyanogen bromide and N-bromosuccinimide, and the resultant fragments were separated by gel chromatography in the presence of 80% (vol/vol) formic acid. The N,N'-dicyclohexylcarbodiimide label was recovered in each organism exclusively in a 17-residue fragment. Further analysis by automated solid-phase Edman degrada.ti.on revealed tha~ the bound label was present at only one positIOn, correspondmg to a glutamyl residue. The NN'~ icyc~ohexyl~a~bodiiJ?1~de-'!l0dified glutamyl residue is the ~nly Id~ntIcal aCidic posItIon m both proteins and occurs in the middle of a hydrophobic sequence of about 25 residues.
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Schulklassenunterricht soll möglichst vielen Schülern ein möglichst hohes kognitives Leistungsniveau erreichen helfen. Nur wenige Unterrichtsstudien haben bisher jedoch zur Aufklärung jener Lehr-Lern-Bedingungen beigerragen, unter denen sich hohe qualifikatorische und varianzreduktive Wirkungen gleichzeitig erreichen lassen. Die vorliegende Studie greift dafür auf Merkmale einer adaptiv-remedialen Lehr-Lern-Organisation zurück und überprüft ihren Erklärungsgehalt im Mathematikunterricht von 58 fünften Hauptschulklassen. Zur systematischen Entwicklung komplexer Erklärungen und ihrer einzelfallartigen Beurteilung wird ein neu entwickeltes Programmsystem (HYPAG) angewandt. Es fühn zur Auswahl einer Annahmenstruktur, in der Instrumental- und Rahmenbedingungen von Schulklassenunterricht in Wechselwirkung stehen, für sich genommen aber nur mehr hinreichende und darin substiruierbare Bedingungen qualifizierender und varianzreduktiver Unterrichtseffekte sind.
Traditionally psychological research had assisted (de lege lata and de lege ferenda) jurisdiction, legislation, and law enforcement. However, the fol1owing three examp1es support the thesis that certain areas of psycho1ogica1 research gain new concepts and hypotheses by considering re1ated juristic thought. First, a developmenta1 study on the judgment about neg1igent damages suggested a three-step deve10pment of the evaluation of neg1igence. That threestep development wou1d contradict Heider's sequence of responsibi1ity levels. Second, a cognitive algebra approach to asses the chi1d's understanding of the duty to compensate the victim for his 1055 caused by a culpab1e actor suggested a two-step deve10pment of understanding that duty. The chi1d of the first deve10pment a1 step wou1d regard giving on1y half compensation of the 10ss as doing his duty to repair damages. Third, the concept of cul pa and the "Strafzumes sungs 1 ehre" in the German juri 5 ti c thought are d i scussed as key concepts for innovating psycho1ogica1 research on a moral algebra. Insofar juristic thought proved to assist psycho1ogica1 theory bui1ding what would make the relation of juristic thought and psycho1ogy a relation of interdependence.
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Kompensation und das Problem der Zuggebbarkeit werden als die beiden wichtigsten Störquellen bei der Erfassung pharmakonbedingter Befindlichkeitsänderungen dargestellt. Gefördert werden diese Prozesse durch eine Zentrierung der Methode auf die Selbstbeobachtung. Es wird die Hypothese aufgestellt, daß die Selbstbeobachtung ersetzbar ist durch eine Beschreibung der "Welt draußen". Die Person kann sich nur in der Welt erleben - folglich werden Veränderungen dieses Erlebnis auch Veränderungen in der Beschreibung der Welt nach sich ziehen. Ausgehend von dieser Hypothese wird ein Experiment konzipiert, in dem die Vpn lediglich die experimentelle Situation und die am Experiment beteiligten anderen Vpn beschreiben, nicht aber sich selbst. Es kann gezeigt werden, daß mit den so gewonnenen Maßen eindeutige Wirkungen des eingesetzten Tranquilizers nachgewiesen werden können, ebenso eindeutige Dosis-Wirkungs-Beziehungen. Die Konsequenzen für eine pharmakopsychologische Methodik werden diskutiert. Zudem wird herausgehoben, daß Tranquilantien dann als positiv bewertet werden können, wenn sie die Reagibilität der Vpn auf die Situation erhöhen und durch eine Verringerung des allgemeinen Aktivierungsniveaus eine adäquate Verarbeitung angstinduzierender Situatonen ermöglichen.
Nichtparametrischer Vergleich von Testprofilen und Verlaufskurven bei unabhängigen Stichproben
(1980)
Werden k Testwerte an zwei oder mehreren Stichproben von Pbn erhoben, stellt sich das Problem des Vergleichs von Testprofilen. Ähnliche Fragen treten auf, wenn statt k verschiedenen Testwerten ein Meßwert zu k Zeitpunkten an einem Pb erhoben wird. Zur Auswertung dieser Fragestellung wird ein Vorgehen nach dem WILCOXON-Rangsummentest vorgeschlagen, der es erlaubt (1) Unterschiede aller Art (2) Unterschiede in der Lage und (3) Unterschiede in der Form der Profile zu prüfen. Das Vorgehen wird an einem Beispiel aufgezeigt. Erweiterungen auf andere Fälle werden diskutiert.
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A substantial literature exists on the coordination of speaking and looking behaviour and their significance as indicators for the production and reception of social information. Within this framework, the temporal organisation of such behaviour has been 'shown to reflect both the coordination within the individual and between participants in a situation. In this paper, it is proposed that observed behavioural sequences may be formally described by rules of syntax, thus implying the likelihood of structural organisation as opposed to, for example, linear time dependence between behavioural states. This being the case, differing sets of rules and grammars respectively can be expected for various social situations. Clinical interviews and discu~sions between couples on a topic of marital conflict were analysed, the on-off patterns of speech and gaze being taken as data. The resulting behavioural repertoire was regarded, in the sense of a formal grammar, as the terminal vocabulary. A set of rewriting rules was determined and their associated probabilities inferred. The situational conditions were found to be reflectedin the syntactic features of the grammatical model - the terminal vocabulary, the production rules and the production probabilities.
In allgemeinpsychologischen Lärmexperimenten ist eine monotone Beziehung zwischen physikalischer Lautstärke und erlebter Lautheit bestens abgesichert. In der vorliegenden Arbeit wird gezeigt, daß diese Beziehung unter Medikationsbedingungen nicht gilt. In einem 3 X 3 X 2-faktoriellen Versuchsplan mit den Faktoren physikalische Lautstärke (weißes Rauschen in 76, 79 und 82 dB), Medikation (Tranquilizer, Plazebo, Stimulizer) und (niedere bzw. hohe) Ansprechbarkeit auf Medikamente beurteilten insgesamt 54 junge weibliche Versuchspersonen in sechs Durchgängen eine Serie von 12 gleichabständigen Lärmstufen von 58 bis 92 dB in bezug auf die erlebte Lautheit. Es war weder eine Hauptwirkung Physikalische Lautstärke noch Medikation aufgetreten, dafür differenzierte die Schichtungsvariable Ansprechbarkeit auf beiden Faktoren. Eine Interpretation der Ergebnisse sensu Eysencks Drogenpostulat und im Sinne einer Aktivierungstheorie wird vorgenommen. Als Konsequenz für pharmakopsychologisches Experimentieren wird die Forderung erhoben, die in das Experiment eingebrachten Unabhängigen Variablen in ihrer Wirkung auf das Erleben der Vpn zu kontrollieren (subjektive Repräsentation des experimentellen Angebotes).
Validität und Reliabilität der Sprechkodierung einer Beobachtergruppe wurden in Abhängigkeit von der zeitlichen Auflösung untersucht. Die Validität wurde anhand der Übereinstimmung der Beobachter mit einem automatischen Sprachdetektor berechnet. Die Reliabilitätswerte für die Kodierung von Sprechen und Blikken ergaben sich aus der Übereinstimmung der Beobachter untereinander. Im wesentlichen zeigten sich folgende Ergebnisse: 1. Die Validität/Reliabilität der Sprechkodierung ist eine monotone, nichtlineare Funktion der gewählten Auflösung. Die systematischen Fehler, die auf Latenz und Trägheit der menschlichen Beobachter zurückgehen, werden bei einer Auflösung von 400 msec nahezu vollständig unterdrückt. 2. Weder bei der Erfassung des Sprech- noch des Blickverhaltens lassen sich Anzeichen für Observer-Drift feststellen. Trainierte und untrainierte Beobachter unterscheiden sich nicht signifikant. 3. Die Kodierung des Sprechverhaltens ist geringfügig reliabler als die des Blickverhaltens. Dieser Unterschied kann in der Praxis vernachlässigt werden.
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Internal characteristics such as depressed mood, anxiety and general negative emotions are accompanied, particularly during depressive illness, by changes in observable behaviour. Accordingly, the following questions may be examined: are intra-individual changes in speech and gaze behaviour related to changes in the internal psychopathological state? Further, do these changes occur synchronously to changes in the state of subjective well-being? A longitudinal study was made on depressed patients. Their behaviour was observed during standardised interviews and diagnostic-therapeutic discussions held at regu~ lar intervals. Various speech and gaze parameters were examined with respect to their coordination and their relationship to the subjective state of well-being. Considerable variation was found in the temporal relationship amongst these variables. The results are discussed with respect to the relevance of speech parameters and the coordination of verbal and nonverbal behaviour as indicators of the psychopathological condition.
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Prostacyclin (PGI2) induced a dose-dependent decrease in blood pressure with slight increases in heart rate and body temperature, when administered at the doses of 0.1-100 ~g into the lateral cerebral ventricle (i.c.v.) of the urethane-anaesthetised rat. When the same doses were administered intravenously, both the blood pressure and heart rate decreased. Central pretreatment wib~ sodiurn meclofenamate (1 mg/rat i.c.v.) antagonised the central hypotensive effect of PGI2 but i.c.v. pretreatrnent of the rats with indomethacin (1 mg/rat) failed to affect the PGI 2-induced hypotension. Central pretreatment with two histamine H2-receptor antagonists, cimetidine (500 ~g/rat i.c.v.) or metiamide (488 ~g/rat i.c.v.), antagonised the blood pressure lowering effect of 0.1 ~g dose of PGI2 but failed to affect the hypotension induced by higher PGI2 doses. Therefore the main central hypotensive effect of PGI2 seems not to be associated with the stimulation of histamine H2 -receptors in the brain. The hypotensive effect of i.c.v. administered PGI2 appears to be due to an action upon the central nervous system rather than to a leakage into the peripheral circulation. This assurnption is supported by the fact that sodiurn meclofenamate i.c.v. antagonised the effect of PGI 2. In addition, the chronotropic response to i.c.v. PGI2 was opposite to that induced by intravenous administration. The results also suggest that there may be differences in the mode of action between sodiurn meclofenamate and indomethacin.
Die Tricarbonyl(germacy~lopentadien)eisen-Komplexe VI-X werden durch Umsetzung der Germacyclopentadiene I-V niit Fe(CO)\(_5\) dargestellt. In l,l-Dialkyl- und -Diaryl-l-gemiacyclopentadien-Komplexen kann die Ge-C( exo )-Bindung durch verschiedene Elementhaloge~de gespalten werden, wobei die I-Halogen-l-germacyclopentadien-Komplexe XII, XIII, XV-XVII gebildet werden. Eine Entkomplexierung des Komplexes XI tritt bei der Reaktion mit Me\(_3\)NO oder TiCl\(_4\) ein. Das Tricarbonyl(l-chlor-l-germacyclopentadien)eisen XII reagiert mit AgF, NaJ, NaOMe und LiAIH\(_4\) zu den Komplexen XIXXXII. Das German XXII kann mit CCl\(_4)\ in XII überführt werden. Die Tricarbonyleisen-Komplexe XI, XII, XVI, XVII und XIX reagieren photochemisch mit Trimethylphosphan zu den Dicarbonyl(trimethylphosphan)-Komplexen XXIII-XXVII. Die Kristallstruktur des Tricarbonyl(l-exo-fluor-1-endo-methyl-2,3,4,5-tetraphenyl-1-germacyclopentadien)eisen wird beschrieben.
No abstract available
The GVHRIL foHowing transplantation of small intestine are different from those found after bone marrow transplantation or spleen cell injections in that they show a remarka ble, significant prevalence of lesions within the intestinal mucosa. These findings are consistent with the observation that jntestinal lymphocytes newly formed in mesenteric lymph nodes predominantly home in on the intestine again.& The degree of histologic alteration within different tissues indicates that the graft and the host may survive the lesions of the lymphatic tissues, whereas the severe intestinal lesions following GVHR may easily cause death of the recipient. With regard to clinical sman bowel transplantation two statements can be made: (l) GVHRIL play a significant role in small bowel trans~ plantation. (2) To minimize their biologic importance, a selective elimination of the graft's Jymph nodes by irradiation or surgical resection should be considered in view of the remarkable difference between GVHRIL in lymph nodes and in the graft's intestinal wall itself.
The aim of this study was to determine whether o-chlorobenzylidene malononitrile ( CS) exhibits any genotoxic activity towards Salmonella or mammalian DNA in vivo. CS was synthesized with a [\(^{14}\)C]-label at the benzylic carbon atom. It was administered i. p. at a dose level of 13 mg/kg (1 mCi/kg) to young adult male rats. Liverand kidney DNA was isolated after 8, 25, and 75 h. The radioactivity was at (liver, 8 and 75 h) or below (all other samples) the limit of detection of 3 dpm. Therefore, a possible binding of CS to DNA is at least 10\(^5\) times lower than that of the strong hepatocarcinogen aflatoxin B1, and 4,000 times lower than that of vinyl chloride. In contrast to this lack of DNA binding, but in agreement with the chemical reactivity of CS, a binding to nuclear proteins could be detected with specific activities ranging between 50 and 121 dpm/mg for liver and between 3 and 41 dpm/mg for kidney. Protein binding could well be responsible for its pronounced cytotoxic effects. Cs was also tested in the Ames Salmonella/microsome assay. Strains TA 1535, TA 1537, TA 1538, TA 98, and TA 100 were used with or without pre-incubation. Only with strain TA 100 and only without pre-incubation, a doubling of the number of revertants was detectable at the highest dose Ievels used, 1,000 and 2,000 !lg CS per plate. With pre-incubation of TA 100 with CS, a slight increase of the number of revertants was seen at 100 and 500 !lg per plate, and a subsequent fall below control values at 1,000 J.tg. A check for the number of surviving bacteria revealed a strong bacteriotoxicity of the higher doses of es so that the calculated mutation frequencies, i.e., the oumber of revertants per number of surviving bacteria, increased with doses up to 500 !J.g. This toxicity could be counteracted in part by the addition of increasing amounts of rat liver microsomes. In the view of these results, and taking into account the rare and low exposure of man, it is concluded that CS will not create a risk for the induction of point mutations or of carcinogenic processes mediated by DNA binding.
Lack of covalent binding to rat liver DNA of the hypolipidemic drugs clofibrate and fenofibrate
(1981)
\(^{14}\)C-Labelled clofibric acid and fenofibric acid were administered p.o. to 200 g male and female rats. After 10 h, liver nuclear DNA and protein were isolated and the radioactivity was determined. Binding to protein was clearly measurable whereas no binding to DNA could be detected from any drug. A comparison of the Iimit of detection of such DNA binding with well-known chemical carcinogens revealed that the known hepatocarcinogenicity of clofibrate cannot be based upon an initiating, DNA damaging, mode of action but must be due to other, nongenotoxic, mechanisms such as peroxisome proliferation, hepatomegaly, or cytotoxicity due to protein binding. The risk assessment in man and the interpretation of the carcinogenicity data for rodents are discussed.
Die Organophosphorsäureester la-4a und ihre Sila-Analoga lb-4b des Typs R\(^1\)R\(^2\)P(O)( p-OC\(_6\)H\(_4\)ElMe\(_3\)) (EI = C, Si) wurden synthetisiert. Die Kohlenstoff-Verbindungen 1 a- 4a zeigen hinsichtlich ihrer Anticholinesterase-Aktivität die gleichen Struktur-Wirkungs-Beziehungen wie die Silicium-Verbindungen 1 b- 4 b. Letztere sind jeweils wirksamer als die entsprechenden C-Analoga.
Das Sila-Dimetacrin (3a), ein Sila-Analogon des Psychopharmakons Dimetacrin (2), und sein N,N-Diethylderivat 3 b sowie sein 3-Chlorderivat 3 c wurden, von den o-Halogenanilinen 4 a- c ausgehend, über die teilweise unbekannten Stufen 5 a- c bis 10a- d synthetisiert, in ihren Eigenschaften beschrieben und in ihrer Struktur über Elementaranalysen, \(^1\)H-NMR- und Massenspektren sichergestellt. Die Synthese des Zwischenproduktes Bis(2-bromphenyl)amin (9a) konnte optimiert werden.
No abstract available
The distribution of lipofuscin in the perikarya of Purkin je cells of vermal and hemispheric lobules has been determined quantitatively in 7 rats, 30-38 months old, by the point-counting method. On the basis of morphologically and statistically significant differences a pigmentarchitectonics of the cerebellar cortex is established. The Purkinje cells of lobule VIa (Larsell 1952) are extremely lipofuscin-rich. The Purkinje cells of the hemispheres, lobules V, Vlb + c and VII contain considerable amounts of a finely granular lipofuscin, the Purkinje cells of lobules I-III and VIII- IXa a globular type of lipofuscin. The Purkinje cells of sublobule XI d c and X are lipofuscin-poor cells. Three types of lipofuscin ha ve been identified in the light microscope.
Nonnucleolar chromatin from interphase nuclei of Physarum polycephalum plasmodia occurs in two different structural configurations as seen in electron microscopic spread preparations. While the majority of the chromatin is devoid of nascent ribonucleoprotein (RNP) fibrils and compacted into nucleosomal particles, a minor proportion (10- 20%) is organized differently and reveals a smooth contour. It is this form of smooth chromatin which is rich in transcription units (mean length: 1.36±0.21 11m). Only occasionally are solitary nascent RNP fibrils observed which are associated with beaded strands of chromatin. In transcribed smooth chromatin nucleosomal particles are not only absent from the transcription units but also from their nontranscribed flan king regions, indicating that this special structural aspect is not merely a direct consequence of the transcriptional process. The existence of ca. 10- 20% of Physarum chromatin in the smoothly contoured form is discussed in relation to reports of a preferential digestibility of a similar proportion of Physarum chromatin by DNAse I (Jalouzot et al. , 1980) and to the altered configuration of "peak A" chromatin subunits after micrococcal nuclease digestion (Johnson et al., 1978a, b).
Jahresbericht 1980
(1981)
No abstract available
Dükers Ergebnisse zur Wirkung von zwangsläufiger Arbeit bei wollensschwachen Vpn konnten wieder eingebracht werden. Die Variation des Versuchsgeräts ergab, daß das Gelingen dieser Untersuchungen wesentlich von der methodisch einzuführenden Unausweichlichkeit der Situation abhängt. Je weniger dies verwirklicht wird, desto geringer ist der Leistungsanstieg, um so mehr tritt die Person des Vls in den Vordergrund, um so schwerer fällt es den Vpn, die Leistungssteigerung der eigenen Person zu attribuieren. Ferner konnte gezeigt werden, daß das Schreiben von Achten in freier und zwangsläufiger Arbeit zumindest dieselbe Wirkung auf andere Leistungen hat wie das direkte üben dieser Leistungen. Offensichtlich wird mit dieser Methode eine zentrale Funktion der Leistung geübt.
Barley stripe mosaic virus (BSMV) RNA which was previously reported to contain poly(A) sequences (Agranovsky et al., 1978) can be specifically esterified with tyrosine in vitro in the presence of an aminoacyl-tRNA synthetase fraction from wheat embryos. All the three RNA components of the BSMV strain with a three-component genome (Norwich) and both RNA components of a two-component strain (Russian) can be tyrosylated. The poly(A)-containing (bound to oligo(dT)-cellulose) and poly(A)-deficient(not bound to oligo(dT)-cellulose) fractions of BSMV RNA display a similar amino acidaccepting ability. The nucleotide sequence which accepts tyrosine is coupled with the intact genomic polyadenylated BSMV RNA. The viral RNA isolated after sucrose density gradient centrifugation under drastic denaturing conditions retains its aminoacylating activity, which suggests that this activity is not due to the presence in a BSMV RNA preparation of a tyrosine tRNA associated with BSMV RNA. Inhibition of aminoacylation of the 3’-oxidized (treated with sodium metaperiodate) BSMV RNA suggests that the tyrosine-accepting structure is localized at the 3’ terminus of BSMV RNA molecules. It is shown that segments of different lengths obtained upon random fragmentation can be tyrosylated. The 3’-terminal (tyrosine-accepting) poly(A)+ segments can be isolated. The shortest segments of viral RNA capable of being aminoacylated [i.e., containing both tRNA-like structure and poly(A)] consists of approximately 150-200 nucleotides. The analysis of the oligonucleotides derived from individual BSMV RNA components labeled with 32P at the 3’ end revealed two types of 3’-terminal sequences different from poly(A). It is suggested that a poly(A) sequence is intercalated between a 3’-terminal tyrosineaccepting structure and the 5’-terminal portion of poly(A)+ BSMV RNA.
The influenza virus H1N1 (the A/USSR/90/77 strain) that reappeared in 1977 after the H1N1 influenza viruses had disappeared from the human population, is compared with the A/FM/1/47 and the A/FW/1/50 influenza viruses by the method of oligonucleotide mapping of individual segments of the viral RNAs. Seven genes of the A/USSR/90/77 virus appear to be very similar to the corresponding genes of the A/FW/1/50 virus, whereas the gene coding for the M protein displays considerable homology to the corresponding gene of the A/FM/1/47 virus. The data demonstrate that the A/USSR/90/77 strain is a recombinant virus.
Comparisons ofrelative lengths oflampbrush loops, nascent RNP transcripts and hnRNA molecules from oocytes of amphibia with different C-values show that there is an increasing trend in loop, and transcriptional unit, length with increase in genome size but no increasing trend with respect to RN A contour length.The formation of duplex regions and circles in RNP fibrils indicates that RNA processing may occur within the nascent fibrils. The hnRNA molecules from oocytes of the various amphibia readily form intermolecular duplex structures. These complementary sequences have a low kinetic complexity and are transcribed from highly repetitive sequences distributed throughout the genome. Their possible function is considered.
Die Struktur von Tetramethylammoniumchloropentacarbonylwolframat wurde rontgenographisch aue Einkristalldaten bestimmt. Die Verbindung kristallisiert mit vier Formeleinheiten in del' monoklinen Elementarzelle (Raumgruppe P2Jc) folgender Dimensionen: a = 1111,3(4) pm, b = 1110,3(4) pm, c = 1204,1(3) pm, f3 = 99,63(3)°, V = 1464,8 . 106 pm' (R = 0,028). Das Anion besitzt annahernd C4v·Symmetrie mit d(W -C(ois» = 203 pm, d(WC( trans» = 197 pm, d(W-Cl) = 256,6 pm. Zwischen Kation undAnion treten keine ungewohnliche Kontakte auf.
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