Le chlore,oligo-élément indispensable pourLemna minor

Zusammenfassung Mit einer nachBroyer undStout gereinigten Nährlösung konnte nicht bewiesen werden, dass Cl^– ein fürLemna minor unentbehrliches Ion sei. Es wurde deshalb eine neue Reinigungsmethode ausgearbeitet, die eine Verminderung des Cl^–-Gehaltes der Nährlösung auf weniger als 10 µg/l erlaubt. In einer derart behandelten Nährlösung zeigtLemna minor folgende Mangelsymptome: Verschwinden der Wurzel, Chlorose und sehr starke Verkleinerung der Blätter. Beigabe von Cl^– zur Nährlösung genügt, um die Mangelsymptome zu verhüten oder sie zu kompensieren. Unter den angegebenen Bedingungen benötigtLemna minor ungefähr 100 µg Cl^–/l.     

Dissociation-constants of metal-ion-complexes with alkaline phosphatase from pig kidney

Summary Using metal-ion buffers it was possible to remove Zn²⁺, Mg²⁺ and Mn²⁺ ions of pig kidney alkaline phosphatase reversibly. The dissociation constants obtained are K_EMg:4·10^–7 M, K_EMn:4·10^–8 M and K_EZn:8·10^–13 M (22°C, pH:9.6, :0.07).Acknowledgement: The authors thank Dr.H. U. Wolf for helpful suggestions and valuable discussion and MissH. Köth for technical assistance.     

Sur l'action de l'acide 2,4-dichlorophénoxyacétique sur la croissance des racines deZea mays et dePisum cultivéesin vitro

Summary (1) A response ofZea mays andPisum roots cultured aseptically to 2,4-dichlorophenoxyacetic acid has been observed.Depending on the concentrationZea mays shows an increase of the growth rate (optimal concentration 10^–11 mol) which turns over to an inhibition (above 10^–7 mol). The curve is similar to that obtained by 3-indoleacetic acid, which proves the phytohormonal character of 2,4-D.(2) ThePisum root is more sensitive than theZea mays root. A concentration of 10^–7 molinhibitsPisum in a high degree, whileZea mays is no more inhibited, thus demonstrating the selective herbicidal action of 2,4-D against isolated roots of Dicotyledons culturedin vitro.     

“... in Christophorum Clavium de Contactu Linearum Apologia” Considerazioni attorno alla polemica fra Peletier e Clavio circa l'angolo di contatto (1579–1589)

Summary In this work 1 focus my attention upon the question of the angle of tangency in the XVI^th Century, especially in the polemic between J. Peletier and Chr. Clavius (1579–1589). The interest in the question favored deliberation about the theory of proportions, the principle of Eudoxus-Archimedes and the set of angles of tangency (this is a non-Archimedian set); there were problems about logical proofs and geometrical proofs.

---

---

Memoria presentata da H. Freudenthal     

Influence of cyclic nucleotides on protein synthesis in vascular smooth muscle

Summary The incorporation of leucice-¹⁴C into protein in bovine mesenteric arteries was augmented by cyclic GMP (10^–3 M) and decreased by cyclic AMP (10^–3 M). There was no effect of 5 AMP (10^–3 M). The phosphodiesterase inhibiting drugs theophylline (10^–3 M) and papaverine (5×10^–5 g/ml) both decreased the leucine-¹⁴C incorporation.We are indebted to Mrs.Lena Burlin for hear assistance. Finacial support has been provided by the Swedish State Medical Research Council (No. 04X-101X-4498).     

Zur Pathogenese des Urämiesyndroms1. Über den Einfluss von Tyramin auf die Acetoinsynthese aus Brenztraubensäure in Rattenleberhomogenat2

Summary Tyramine enhanced the production of acetoin from pyruvate in rat liver homogenates. A stimulation of acetoin synthesis was only observed, when tyramine was oxidized during the incubation. Tyrosol (p-hydroxyphenylethanol) stimulated acetoin synthesis whereasp-hydroxyphenylacetic acid and ammonia were ineffective.

---

---

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

---

8. Mitteilung. 1. Mitt.:H. Thölen, F. Bigler undH. Staub, Path. Microbiol. (Basel)24, 262 (1961). — 2. Mitt.:F. Bigler, H. Thölen undH. Staub, Helv. physiol. Acta19, C 11 (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). — 5. Mitt.:H. Thölen, F. Bigler, A. Heusler, W. Stauffacher undH. Staub, Exper.18, 454 (1962). — 6. Mitt.:F. Bigler, H. Thölen undH. Staub, Schweiz. med. Wschr.92, 746 (1962). — 7. Mitt.:F. Bigler, H. Thölen undH. Staub, in Vorbereitung.     

Über die Gestalt von Fadenmolekülen in Lösung

Summary Some arguments put forward byG. Bier in a recent article in order to supportH. Staudinger's assumption that chain molecules in solution should behave like straight rigid rods are examined. It is shown that the assumptions made byG. Bier are largely arbitrary. The main argument is the assumption that the C-C-bond in long chain molecules should not show any rotation. As far as this point is concerned, attention is drawn to some recent publications showing that the viscosity of shape of chain molecules can be determined by experiment (specific viscosity and double refraction of flow at high velocity gradients). According to these determinations the time necessary for a complete change of shape, using partially free rotation, is of the order of 10^–5–10^–3 seconds for molecules like nitrocellulose or polystyrene up to degrees of polymerization of several thousands and for viscosities of the solvent of the order of 10^–2 poises.     

Negative adsorption of anions by suspensions of bentonites

Résumé Nous avons étudié l'adsorption négative des anions I*O ₃ ^– et Cr*O ₄ ^–– à différents bentonites en fonction d'électrolytes additionnés. Pour les électrolytes NaCl et Na₂SO₄ les résultats sont en bon accord avec ceux deSchofield etMattson; nous avons étudié aussi l'effet de l'addition de solutions de CaCl₂; celles-ci produisent le même effet à des dilutions 20 fois plus grandes que les solutions de NaCl. Comme ceci ne peut pas être expliqué sur la base de la théorie deDebye-Hückel, nous avons appliqué la théorie exacte de la couche double; le facteur 20 mentionné plus haut mène à une valeur de=–75 mV. En introduisant cette valeur de, une représentation graphiques–1/c pour les résultats des expériences au Na-bentonite + solutions de NaCl, donne une surface spécifique de 1110 m²/g.     

Cell wall degradation in senescing tobacco leaf discs

Zusammenfassung In ausgestanzten Blattstücken vonNicotiana tabacum, welche auf Wasser schwimmend inkubiert werden, findet im Verlauf von 7 Tagen ein beträchtlicher Abbau der Hemizellulose statt. Benzyladenin (10^–5 M) verzögert den Abbau, Abscisinsäure (5×10^–5 M) verstärkt ihn. Der Gehalt an Zellulose verändert sich im Verlauf der Alterung kaum.

---

---

The author is indebted to Dr.A. Artho and to theF. J. Burrus & Cie, Manufacture de Cigarettes, Boncourt, Switzerland, for generously supporting the present work. The skillful technical assistance of MissM. Schellenberg and the supply of abscisic acid by Hoffmann-La Roche, Basel, are gratefully acknowledged.     

Folic acid and the inhibition of brain L-glutamic decarboxylase

Summary Folic acid competitively inhibited brainl-glutamic decarboxylase (K _i=1.62×10^–3 M). This inhibition could possibly be associated with epilepsy.This work was supported by the United Parkinson Foundation.     

Geometrical constructions equivalent to non-linear algebraic transformations of the plane in Newton's early papers

Summary The theory of constructive formation of plane algebraic curves in Newton's writings is discussed in § 1: the apparatus by which Newton forms the curves, Newton's theorems on forming unicursal curves, his theory of conics, and his theory of (m, n) correspondence. Special Cremona plane and space transformations obtained by Newton's organic method are dealt with in § 2. The article ends with § 3, which shows two different directions in the theory of the constructive formation of plane algebraic curves in the XVIII-XIXth centuries. A synopsis is appended.Abbreviations MPN The Mathematical Papers of Isaac Newton, edited by D. T. Whiteside, Vols. 1–3, Cambridge, 1967–1969 - Hudson H. Hudson, Cremona Transformations in Plane and Space, Cambridge, 1927 - PT (abridged) Philosophical Transactions of the Royal Society 1665–1800 (abridged), London, 1809 - Andreev ₁ K. A. Andreev, On geometrical correspondences ... (in Russian), Moscow, 1879 - Andreev ₂ K. A. Andreev, On the Geometrical Formation of Plane Curves (in Russian), Kharkov, 1875     

Effects of three synthetic peptides analogous to neurohypophyseal hormones on the excitability of giant neurones ofAchatina fulica Férussac

Summary Deamino-dicarba-(d-d-)oxytocin andd-d-Arg-vasotocin at 10^–4 kg/l showed an excitatory effect on the periodically oxcillating neurone (PON) ofAchatina fulica Férussac.d-d-Arg-vasopressin had no effect.     

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.

---

---

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

---

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).     

Alkaloid studies XXIII isolation of four new aspidosperma alkaloids: Cylindrocarpine,refractine, pyrifoline,and pyrifolidine

Zusammenfassung Die Isolierung von vier neuenAspidosperma-Alkaloiden ergabCylindrocarpin (erstes N-Cinnamoyl-dihydroindolderivat) sowieRefractin, Pyrifolin undPyrifolidin (alles N-Acetyl-dihydroindole), die alle vier eine Methoxylgruppe im Dihydroindolsystem besitzen.

---

---

Postdoctorate research fellow 1958–1959 (Wayne State University); 1959–1960 (Stanford University).

---

Paper XXII,J. S. E. Holker, M. Cais, F. A. Hochstein undC. Djerassi, J. org. Chem.24, 314 (1959).     

CMR spectral analysis of tetrahydrocannabinol and its isomers

Zusammenfassung Die¹³C-NMR-Spektren des Tetrahydrocannabinols und seiner Isomeren wurden aufgenommen und vollständig analysiert.

---

---

Carbon-13 Nuclear Magnetic Resonance Spectroscopy of Naturally Occurring Substances. IX. For the preceding article seeE. Wenkert, C.-J. Chang, D. W. Cochran andR. Pellicciari, Experientia28, paper No. 1099 (1972).

---

U.S. Public Health Service predoctoral fellow, 1967–1971.

---

U.S. Public Health Service predoctoral fellow, 1969–1972.     

The growth of cell membranes during synchronized cell division ofSaccharomyces cerevisiae

Riassunto Cellule diSaccharomyces cerevisiae venivano coltivate in brodo centenentel-Leucina-³H o³²PO ₄ ^– raccolte in fase log e quindi coltivate in modo sincrono in nuovo terreno privo di radioisotopi. Le cellule e le gemme venivano separate per centrifugazione su gradiente di saccarosio, quindi si isolavano le membrane. La radioattività specifica nelle membrane purificate risultava circa il 50% di quella presente inizialmente nelle cellule usate per la coltura sincronizzata.     

Die Synthese des Novobiocins

Summary The synthesis of the antibiotic novobiocin is described. First the essential carbohydrate, the 3-O-carbamoylnoviose was synthesized fromd-glucose. A number of steps (1–6) led to the 3,5,6-tri-O-benzyl-2-O-methyl-d-galactono--lactone (6) which is characterized by the correct array of carbon atoms inherent to the noviose. Further transformations (7–15) finally yielded the carbohydrate. The problem of glycosidation is discussed in some detail. Glycosidation of a suitable aglycon precursor (18) with 2,3-O-carbonyl--noviosyl-chloride (22) proved possible and led to the isolation of an-glycoside (23) which was further transformed (24–28) into novobiocin.

---

---

Chemische Forschungsabteilung der F. Hoffmann-La Roche & Co. AG, Basel.

---

Vortrag Dr.B. P. Vaterlaus, gehalten an der Gordon Research Conference on Steroids and other Natural Products, 16.–20. Juli 1962, New Hampton, N.H., USA, und vor der Basler Chemischen Gesellschaft, 8. November 1962. Im Auszug:H. Spiegelberg,Synthèse du 3-O-carbamoylnoviose, sucre de la novobiocine, Symposium international de chimie organique, Bruxelles, 15. Juni 1962;J. Kiss,The Synthesis of Noviose and Allied Compounds, Birkbeck College (Univ. London), 23. Oktober 1962. Der vorliegende Aufsatz ist Gegenstand von Detailpublikationen in den Helv. chim. Acta, in Vorbereitung (1963).     

Triazine nucleic acid interrelationship inEscherichia coli 15 arg− t − u −

Zusammenfassung Mit Hilfe von 5-Bromuracil wurde die prinzipielle Fähigkeit vonEscherichia coli 15 arg^– t ^– u ^–, Basenanaloge des Pyrimidins für die Synthese ihrer Nukleinsäuren zu verwenden, gezeigt. Ein Einbau der Triazinverbindungen Atrazin und Prometryn in die Nukleinsäuren vonE. coli 15 arg^– t ^– u ^– findet nicht statt, unabhängig, ob die Mikroorganismen in komplettem oder Basen-defizitärem Nährmedium wuchsen.     

Nachweis von Scilliglaucosidin in den Zwiebeln vonBowiea volubilis Harvey

Summary Hellebrigenin was converted to Scilliglaucosidin-19-ol and 3-Epi-Scilliglaucosidin-19-ol. This proves the correctness of the assumption ofStoll et al. ³ that the aldehydic group of Scilliglaucosidin is in position C-10.Comparison of a reduction product of Nabogenin, a substance isolated earlier from the bulbs ofBowiea volubilis Harvey, with Scilliglaucosidin-19-ol and 3-Epi-Scilliglaucosidin-19-ol showed its identity with the first named compound. This proves that the so called Nabogenin was a mixture consisting mainly of Scilliglaucosidin.

---

---

8. Mitteilung über die Glykoside vonBowiea vocubilis Harvey und 162. Mitteilung über Glykoside und Aglykone.

---

7. Mitt.:A. Katz, Helv. chim. Acta38, 1565 (1955).

---

161. Mitt.:H. Kündig-Hegedüs undO. Schindler, Helv. chim. Acta39, 904 (1956).     

Quantitative determination of amino acids in the 10−14 molar range by scanning microscope photometry

Zusammenfassung Die beschriebene Methode stellt eine Kombination der Mikrochromatographie und der Scanning-Mikroskop-Photometrie dar und ermöglicht eine quantitative Bestimmung von C¹⁴-markierten Dansyl-Aminosäuren in biologischen Material im Bereich von 10^–14 M.

---

---

Supported by the Deutsche Forschungsgemeinschaft.

---

We would like to thank Prof. Dr.K. H. Gertz and Priv.-Doz. Dr.H. Stolte for helpful discussion.