Die biosynthetische Inkorporation von externem S35O2 in Glucobrassicin

Summary In plants of theBrassica oleracea species contaminated with S³⁶O₂, incorporation of radioactive sulphur into glucosinolate glucobrassicin has been found. The label is present also in the isothiocyanate group of glucobrassicin, which by decomposition under the action of myrosinase liberates labelled thiocyanate.     

Die Einlagerung von radioaktivem Schwefel in die Flügel von Acrididen nach Applikation von35S-Natriumsulfat-und35S-l-Cystinlösungen

Summary Psophus stridulus L. andOedipoda coerulescens L. were fed or injected with solutions of Na ₂ ³⁵ SO₄ and³⁵S-l-cystine. The radioactive radiation pattern of the wings was found to depend on the time of application. Differences in radiation intensity were found to correspond to the red, blue and dark areas.     

Zum Vorkommen von Thiothreonin im Pflanzenmaterial

Summary In extracts of H₂ ³⁵S gased pea seedlings, a radioactive substance has been revealed by thin layer chromatography which showed the same chromatographic properties as thiotheronine.     

Über die Verwendung von künstlichen radioaktiven Isotopen zur Erzielung von lokalisierten biologischen Strahlenwirkungen

Summary The author made a first attempt to utilize an artificial radioactive isotope for the production of localized biological radiation-effects, by means of intraperitoneal injections of radiozinc (Zn⁶³) suspended in a solution of pectine. Experiments were performed on mice and rabbits and the procedure was applied, for the purpose of preliminary therapeutic investigations, to a case of carcinoma of the ovary with severe peritoneal extension.     

Abbauprodukte von Simazin in Gramineen

Summary Coix lacryma-jobi L., about 20 days old and grown on watercultures, were fed with¹⁴C-ring-labelled simazine. After freeze drying, the plant tissue was extracted with chloroform and 80% ethanol. The ethanol extractable activities were fractionated on a cation exchange column. The radioactive metabolites seem to be identical with 2-hydroxy-4, 6-diethylamino-s-triazine (hydroxysimazine), 2-hydroxy-4, 6-diamino-s-triazine (ammelin) and 2-hydroxy-4-ethylamino-6-amino-s-triazine.     

Einfluss der Wurzeln auf die Trigonellinsynthese beiCoffea arabica

Summary Young plants ofCoffea arabica were fed 200 µC C¹⁴O₂ each, the carbon dioxide being absorbed by photosynthesis. The specific activity of the alkaloid trigonelline contained in the leaves was shown to be strongly dependent of leaf age. Excised plants without root system or plants with an interrupted shoot-root connection as regards pholem transport (by girdling the stem below the cotyledons) incorporate more radioactive carbon into the molecule of trigonelline than intact plants.     

Kaurene biosynthesis in intactPhaseolus coccineus suspensors

Summary Intact suspensors fromPhaseolus coccineus seeds incorporate 2-(¹⁴C)-MVA into a number of radioactive compounds, among which kaurene was identified by GC-MS. This result confirms that the kaurene biosynthetic pathway previously shown for cell-free extracts is active in intact tissues as well.     

Microbial influence on the sorption of137Cs onto materials relevant to the geological disposal of radioactive waste

Summary A major concern in the geological containment of radioactive wastes is the speed of movement of radionuclides from the repository, after their eventual leaching and release, into the geosphere and finally into the biosphere. Radionuclide sorption onto the host rock is an important retarding mechanism. Experimental evidence shows that the presence of microbes in this environment influences the sorption capabilities of the host rock. Their presence can decrease the amount of retardation of¹³⁷Cs, a common radionuclide in radioactive waste, by the solid phase. Sorption methods and data analysis procedures are presented and the implications for radioactive waste disposal assessments are discussed.     

Active transport of [32P]thiamine diphosphate inEscherichia coli

Summary Active uptake of [³²P]thiamine diphosphate byE. coli was analyzed using an improved method of gel filtration chromatography. The radioactive coenzyme was accumulated without dephosphorylation. From this result it was concluded that thiamine kinase is not involved in the membrane transport of thiamine inE. coli.We are indebted to Miss M. Abe for her technical assistance.     

Zur Biosynthese von Biopterin in Säugetieren

Summary Biosynthesis of biopterin in mice and rats was studied. After vascular injection of¹⁴C-GTP (U) in mice and rats, radioactive biopterin was isolated from the urine. The specific radioactivity of 6-carboxypterin obtained by oxidation of biopterin was proved to be 7/9 that of biopterin. The result definitely shows that biopterin is biosynthesized from GTP in mice and rats, and the sidechain of biopterin is derived directly from the ribose moiety of GTP.     

Influence of phenobarbital and TCDD on the hepatic metabolism of TCDD in the dog

Summary The influence of phenobarbital and TCDD pretreatment on the formation and biliary excretion of TCDD-metabolites following single doses of³H-TCDD was investigated. Without pretreatment, 24.5% of the absorbed³H-TCDD dose was excreted in the bile within 110 h. Phenobarbital did not influence this rate, whereas a single dose of 10 g of unlabeled TCDD/kg b.wt nine days earlier resulted in a doubling of the amount of radioactive material eliminated in the bile (47.4%).     

De l'emploi d'isotopes radioactifs artificiels,dans le but d'exercer un effet radio-biologique localisé

Summary One of the authors has previously reported on a method which consists in the utilization of an artifical radioactive isotope (Zn⁶³), suspended in a suitably prepared solution ofpectin, for the production oflocalized biological radiation effects.This « macromolecular occlusion » of the radioactive isotope enables one to perform intraperitoneal injections (in cases of cancer of the ovaries with severe metastatic peritoneal extension), evidently also instillations in cavernous organs, and furthermore direct intratumoral injections, without diffusion of the radioactivity outside the treated areas, as shown both by autoradiographs and controls of blood and urine specimens with a Geiger counter.The authors investigated further whether this procedure would also be suitable for obtaining, by means ofintravenous injections, alocalized radiation effect within thelungs, as presumably the radiozinc, held in the large molecules of pectin, could thus be retained in the pulmonary capillaries. Intravenous injections of such a pectin solution containing radiozinc were performed on rabbits, and autoradiographic controls gave evidence of this expected fixation within the lungs.For the purpose of preliminary clinical investigation 40 millicuries of Zn⁶³ suspended in 6 cm³ of a 3 p. c. isotonic pectin solution were injectedintravenously in a female patient with mainly pulmonary metastases of a previously operated hypernephroma. This patient had been also submitted to X-ray therapy. In spite of a poor general condition, the injection was well tolerated. Autoradiographic controls showed quite clearly that the radioactivity remains precisely localized within the pulmonary areas. No radioactivity whatsoever was demonstrated with the counter in the urine eliminated by this patient after the injection, a fact which points to a rather amazing accuracy of the fixation of the radiozinc in the lungs. This first clinical experience seems quite interesting in view of improving the therapeutic possibilities of pathological, especially neoplastic pulmonary conditions.     

Essai d'identification des corticostéroïdes sécrétés par la surrénale embryonnaire de Veau cultivée in vitro

Summary Pieces of foetal bovine adrenals were cultured in vitro in the presence of¹⁴C-1 sodium acetate. The following radioactive corticosteroids were sought: aldosterone, cortisone, hydrocortisone, corticosterone, 11-dehydrocorticosterone, 11-deoxycorticosterone and 11-deoxy-17-hydroxycorticosterone. Four of them have been identified by thin-layer radiochromatography and derivative formation, i.e. hydrocortisone, corticosterone, 11-dehydrocorticosterone and 11-deoxycorticosterone.     

Hormonal control of manganese transport in the mouse thyroid

The present study deals with a possible mechanism controlling the transport of manganese (Mn), an essential trace element, from the circulation to the thyroid. Mice were pretreated with propylthiouracil (PTU) or triiodothyronine (T₃), and a measurement of the thyroid:serum concentration ratio (T/S) of radioactive manganese (⁵⁴Mn) was carried out. The T/S of⁵⁴Mn was greatly enhanced by PTU, but reduced by T₃. Several methods were used to demonstrate that the T/S of⁵⁴Mn depends upon the level of thyroid-stimulating hormone (TSH) in the serum. First, bovine TSH was injected into mice; an increase in the T/S resulted. Secondly, serum thyroxine and T₃ levels measured by radioimmunoassay (RIA) suggested that PTU produced an increase in serum TSH and T₃ a decrease. However, direct measurement of mouse TSH by RIA for rat TSH failed to produce proof of any changes in TSH level, owing to poor cross-reactivity. Taking all the information into account, it is concluded that Mn-transport into the thyroid is controlled by the thyroid state.     

Über die Beeinflussung der Ca-Aufnahme in Lipidextrakte aus Mikrosomen und Mitochondrien des Herzens durch Digitoxin

Summary Lipids were isolated by chloroform-methanol extraction from mitochondrial and microsomal fractions of guinea-pig hearts. In the presence of digitoxin (10^–9-10^–6 g/ml) 15–30% more radioactive Ca was taken up by the lipid extracts than under control conditions, but the total amount of Ca in this phase remained unchanged. Thus, digitoxin produced an increase in the specific activity of the lipid-bound Ca which may be explained by an increased exchangeability of this Ca fraction. This effect of digitoxin might result in an improved availability of the lipid-bound Ca for Ca-dependent functions (e.g. contraction) of the heart muscle cell.     

Zur klinischen Bedeutung des autoradiographischen Verfahrens bei der Verwendung von kurzlebigen künstlichen radioaktiven Isotopen (Autoorganographie,Autoangiographie)

Summary The author demonstrates the possibility to realize on living human individuals big sizeautoradiographs afterintravenous injections of an artificial radioactive isotope of a relatively short activity. Strong preparations (100 millicuries) of radiozinc (Zn⁶³) in form of soluble oxide have been employed. These injections were performed on two patients suffering from general carcinosis. The humanauto-organographs (autohepatographs, automammographs, autonephrographs, etc.), as well as theautoangiographs of the blood vessels of the skin and the subcutaneous tissues, thus realized for the first time, are quite interesting. The possibilities of a clinical utilization of such autoradiographs are briefly discussed.     

The metabolism of methadone by cultured mammalian cells

Summary Rat hepatoma tissue culture cells and mouse leukemic cells were found to metabolize [1-³H] methadone to at least 2 unidentified radioactive compounds. These results suggest that cultured cells may be useful models for studying methadone metabolism by specific cell types.This study was supported by United States Public Health Service Research Grant No. MH 15622. The illustrations were prepared by Diane J. Kastelic.     

Microbial legradation of bitumen

Summary Bitumen is commonly employed as a matrix for the long-term storage of low and intermediate level radioactive waste. As bitumen can be degraded by microbial activity, it is of great significance to determine the rates at which it may occur in nuclear waste repositories.Experiments have been carried out under optimal culture conditions using bitumen with a highly increased surface area. The potential of different microbial consortia to degrade bitumen has been examined. The investigations showed clearly that bitumen-degrading organisms are ubiquitous. In general the organisms formed biofilms on the accessible substrate surface area. Under oxic culture conditions a bitumen degradation rate of 20–50 g bitumen · m^–2· y^–1 leading to a CO₂ liberation of 15–40 l was observed. Anoxic conditions yielded a 100 times smaller degradation rate of 0.2–0.6 g bitumen · m^–2 · y^–1 and a CO₂ production of 0.15–0.45 l.Based on linear extrapolation the experimentally determined degradation rates would lead to a 25–70% deterioration of the bitumen matrix under oxic and 0.3–0.8% under anoxic conditions within 1000 years.     

Umwandlung von radioaktivem Cortexon in Aldosteron durch Nebennieren-Enzyme

Summary Cortexone labeled in the 21-position with C¹⁴ yielded radioactive Aldosterone through incubation with beef adrenal homogenate. Its activity, due entirely to the 21 carbon atom, showed that about 48% of the Aldosterone had arisen from a direct conversion of cortexone without intermediate degradation. The low yield by weight in this conversion suggests, however, that cortexone is not the only natural precursor for Aldosterone in the adrenal.The radioactivity of the corticosterone obtained showed that about 84% of it originated from added cortexone. Lack of radioactivity of the hydrocortisone confirmed that it does not essentially result from cortexone.

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134. Mitteilung über Steroide. Auszugsweise vorgetragen am 3. August 1955 anlässlich des 3. Internat. Kongresses für Biochemie in Brüssel. 133. Mitteilung sieheE. Vischer, Ch. Meystre undA. Wettstein, Helv. chim. Acta38, 1502 (1955).     

Dehydration of the brain by intra-peritoneal injections of hyper-osmotic solutions of γ-aminobutyric acid anddl-α-alanine

Résumé Utilisant une technique radioactive avec le³HOH, nous avons montré que les injections i.p. des solutions hyperosmotiques de l'acide-aminobutyrique et dedl--alanine, deshydratent de manière significative les cerveaux des souris.

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This study was supported by the U.S.P.H.S.