Synthese des Neopodophyllotoxins und der Podophyllinsäure

Summary Methanolysis of podophyllotoxin (I) with ZnCl₂ as catalyst yields podophyllinic acid methyl ester (IV) and neopodophyllotoxin (V), a new isomer of podophyllotoxin. Neopodophyllotoxin which contains the lactone group in the 1,3-position is stereospecifically hydrolyzed by alkali to the hitherto unknown podophyllinic acid (VI).

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12. Mitteilung über mitosehemmende Naturstoffe.     

Purin- und Pyrimidinbasen der Desoxyribonukleinsäure des Ehrlichschen Mäuse-Ascites-Karzinomas

Summary The proportion of purines and pyrimidines in the DNA of the Ehrlich mouse ascites carcinoma is examined and compared with the base proportion of the DNA from liver and kidney of the normal mouse. The following findings were obtained: The DNA of the ascites tumor contains more guanine and less cytosine and thymine than the DNA of the normal mouse. For guanine this difference is statistically significant. The changed base compound is discussed with regard to the changed growing rate in tumors and the altered chromosome structure in the Ehrlich ascites carcinoma.

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Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft.     

Zur Konstitution von Helvolinsäure und Cephalosporin P1

Summary On the basis of nuclear magnetic resonance measurements and in agreement with recently reported mass-spectrometric investigations it is shown that the molecular formulae of Helvolic acid and Cephalosporin P₁ must be revised to C₃₃H₄₄O₈ and C₃₃H₅₀O₈ respectively, and that the additional carbon atom is present as an angular methyl group.A comparison with the data obtained with fusidic acid points to a similarity among the three substances which is closer than hitherto suspected.     

Über den Umsatz von Anthranilsäure mit Brenztraubensäure

Summary Using series of different reactions it has been possible to demonstrate that the tricarboxylic acid arising from anthranilic acid and pyruvic acid has not the constitution I but is correctly represented by IV. Several derivatives of this tricarboxylic acid were shown to have formulae that are in sharp contrast to those found in literature.     

Zur Pathogenese des Urämiesyndroms. Brenztraubensäure,Acetoin und 2,3-Butylenglykol in Blut von Patienten mit Nieren- und Leberkrankheiten

Summary Acetoin and 2, 3-butylene glycol in blood of renal and hepatic patients are raised, when consciousness is disturbed. There is no correlation between blood levels of acetoin and 2, 3-butylene glycol and the degree of impairment of consciousness. Simultaneous determinations of acetoin and 2, 3-butylene glycol in blood and cerebrospinal fluid show that alterations of the cerebral pyruvic acid metabolism are difficult to detect in circulating blood.

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Mit Unterstützung des «Schweizerischen Nationalfonds» und der Firma F. Hoffmann-La Roche & Co., AG, Basel.

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5. Mitteilung. — 1. Mitt.:H. Thölen, F. Bigler undH. Staub, Path. Microbiol.24, 262 (1961). — 2. Mitt.:F. Bigler, H. Thölen undH. Staub, Helv. physiol. Acta19, C11 (1961). — 3. Mitt.:H. Thölen, F. Bigler undH. Staub, Exper.17, 359 (1961). — 4. Mitt.:F. Bigler, H. Thölen undH. Staub, Schweiz. med. Wschr.91, 1259 (1961).     

Mutation und Phänokopie bei Säugetier und Mensch

Summary The concept of phenocopy established byGoldschmidt in 1935 is critically studied and special emphasis is placed upon the problem of how to distinguish true and false phenocopies. A comparison is made with true and false genocopies, that means mimic mutations. Regarding a given character it is often hard to distinguish as far as man and mammals are concerned, whether it is caused by mutation or phenocopy. Although most of the abnormalities occur as hereditary as well as non-hereditary types, there are, however, hereditary defects that occur seldom and others that occur frequently as phenocopies; still other abnormalities are known as yet only as non-hereditary modifications. It is still impossible to give exact figures for the numerical relationship of single hereditary and non-hereditary abnormalities in man.In certain cases in man and animals there may be also an interaction of the gene and the phenocopying agent, the latter replacing the missing second allele of the gene in question in a heterozygotic individual. The question has to be examined whether in the case of horizontal inheritance, that means occurrence of the same character only in one sibship, a hereditary effect is only simulated with the same phenocopying factor continually in effect. Finally a method is given to determine the relationship of mutations and phenocopies of the retinoblastoma, a hereditary or exogenous caused highly malignant ocular neoplasm in man, a question very important to eugenics.

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Dem PathologenRobert Rössle* zum 80. Geburtstag am 19. August 1956 gewidmet

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Redaktionelle Anmerkung. Am 21. November 1956 ist Herr Prof.Rössle in Berlin verstorben. Die Experientia-Leser erinnern sich dankbar an seinen Aufsatz: «Warum sterben so wenig Menschen eines natürlichen Todes?» Exper.4, 295 (1948).

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Nach einem Vortrag an der Universität Nagoya (Japan) am 17. September 1956.     

Neue Totalsynthese einer razemischen Doisynolsäure

Summary A new synthesis is described of a crystalline 7-methyl-doisynolic acid showing a strong estrogenic activity. This acid is probably identical with the stereoisomer C ofAnner andMiescher. Demethylation of this methoxyacid yields a new doisynolic acid of mp. 113–117° (hemihydrate).

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XIII. MitteilungSynthetische Versuche in der Gruppe der östrogenen Hormone; XII. Mitteilung siehe Chem. listy50, 2004 (1956).     

Gewebsreaktionen nach Implantation von Hyaluronsäure

Summary A report is given on the histological findings after the application of hyaluronic acid to the tibiae of adult guinea pigs. The possible importance of these findings for human medicine is briefly discussed and the results so far obtained in humans are given.

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Vorläufige Mitteilung     

Cysteamin-N-essigsäure,ein neuer Strahlenschutzstoff

Summary The preparation of cysteamine-N-acetic acid, a new X-ray protecting substance, is described and some pharmacological properties are given.     

Folsäure als Cofaktor biologischer Reaktionen

Summary Tetrahydrofolate requiring enzymes catalyze three types of biochemical reactions,viz. formylation, hydroxymethylation, and methyl group formation. Their chemistry and mechanism of action is discussed on the molecular level. There is evidence, from model reactions, that the ethylene diamine grouping in tetrahydrofolic acid is the active center of the cofactor. Its condensation with one-carbon compounds, together with those of the labile hydride ion of the tetrahydropteridine ring, make clear the enzymatic steps by which the one carbon fragment is activated, transferred, and reduced. In cell metabolism, these cycles are geared together by the key compound N(5), N(10)-methylene tetrahydrofolic acid. Through a TPN-linked oxidation, N(10)-formyl tetrahydrofolic acid is produced, from which energy can be derived; by intramolecular reduction, the methyl group is formed.

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Nach einem Vortrag, gehalten auf der gemeinsamen Tagung der schweizerischen, deutschen und französischen Biochemiker, Zürich (Schweiz), 12, 10, 1960.     

Der Antagonismus von schwefliger Säure und Äthanol im Hinblick auf die NNR.-Funktion

Summary Ethanol lessens the stress effect which is produced by application of sulphureous acid.     

Chemotaxine und Kapillarpermeabilität

Summary Bacterial polysaccharides, which exhibit an intense specific stimulating effect on the migration of leucocytes, provoke no trypan blue reaction on the intracutaneous vesicle. Certain mucoproteins show both effects, others only provoke the formation of vesicles. Both reactions are thus separable components of the phenomenon of inflammation.     

Oxydation von Bernsteinsäure durch Leber akut urämischer Ratten

Summary The oxydative desamination of amino acids in the liver of acute uremic rats is increased. Simultaneously the citric acid cycle in the liver of these rats is stimulated. It is suggested that the ketone-acids formed by the increased amino acid degradation are removed by the activated citric acid cycle.

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5. Mitteilung über Untersuchungen der Rest-N-fraktionen bei Urämie

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Die vorliegende Arbeit wurde mit Unterstützung des Schweizerischen Nationalfonds durchgeführt.     

Genetisch bedingte Tumoren und der Gehalt an freien Aminosäuren bei lebendgebärenden Zahnkarpfen (Poeciliidae)

Summary The F₁- and F_nR-hybrids ofPlatypoecilus maculatus andXiphophorus helleri (Poeciliidae), producing melanomase spontaneously, contain essentially more free amino acids than the initial species. Further experiments show that the abnormally high content of free amino acids is connected with the spontaneous formation of tumors.

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Den Herren Prof. Dr.G. de Lattin (Zoologisches Institut Saarbrücken) und Prof. Dr.B. Eistert (Institut für organische Chemie Saarbrücken) sind wir für die stete Förderung dieser Arbeit zu grösstem Dank verpflichtet. Den Herren Prof. Dr.C. Kosswig (Hamburg), Prof. Dr.M. Gordon (New York) und Dr.H. Breider (Würzburg) sind wir für viele Anregungen und die freundliche Überlassung von Zuchtstämmen sehr dankbar. — Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.

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F. Anders, F. Vester, K. Klinke undH. Schumacher, Biol. Zbl., im Druck.     

Effekt der Perjodsäure auf die Erythrocytenmembran

Summary M/2 up to M/500 HJO₄ produces a very peculiar ductility of native erythrocyte membranes, whereas a similar effect is hardly observed on the membranes of trypsin-treated erythrocytes. This observation demonstrates indirectly, probably for the first time, the morphological existence of a loose protein-layer assumed by one of the authors to be present on the surface of erythrocytes.     

Der Einfluss der Pantothensäure,des Pantethins und des phosphorylierten Pantethins auf die Carotinbildung beiMucor hiemalis

Summary Pantothenic acid, pantethine, and probably also phosphorylated pantethine stimulate the production of carotenoids by the fungusMucor hiemalis.     

Kälteeinfluss und Peptidase-Aktivität von Bakterien

Summary The effect of freezing on the peptidase activities of some bacteria and their cell-free enzyme preparations has been studied. Significant differences were found in the activity of peptidase and in their temperature coefficient.     

Die Wirkung von D-Lysergsäure-diäthylamid (LSD 25) und 5-Oxytryptamin auf die Chromatophoren vonPoecilia reticulatus

Summary D-lysergic acid diethylamide (LSD 25) has a characteristic effect on the chromatophores of the female fish guppy (Poecilia reticulatus). This effect can be prevented by prophylactic administration of 5-hydroxytryptamine (serotonin, enteramine).     

Neue Beiträge zur Vegetations- und Klimageschichte der nord- und mitteleuropäischen Interglaziale

Summary Report on recent research on the Quaternary development of flora, vegetation and climate in Northern and Central Europe with schematized diagrams from various papers byFlorschütz, Lona, Szafer and others showing characteristic differences between the older and the newer Interglacials, designed by the present author.