Action d'un hépatome ascitique du rat sur les acides nucléiques du pancréas et du rein

Summary Animals having an ascites hepatoma show an increase in the incorporation of P³² into ribonucleic acid and desoxyribonucleic acid of the pancreas, whereas no change is seen in the kidneys. The variations noted in the pancreas may be compared with those observed previously in the liver and the adrenals. It can therefore be presumed that a substance which stimulates biosynthesis or disrupts the normal metabolic balance is produced by the ascites cells.

---

---

Travail effectué avec l'aide matérielle de l'Institut National d'Hygiène.     

Action de la ribonucléase sur les cellules du carcinome d'Ehrlich

Summary The reduced form of ribonuclease acts on the cells ofEhrlich's carcinoma by producing important changes in the RNA content of cells:(1) First, there is an important synthesis of intracellular RNA and an accumulation of free nucleotides (from the external medium). This phenomenon accompanies the necrosis of the cells.(2) After this first stage begins a rapid degradation of intracellular RNA.Simultaneously, the respiration of cells decreases whilst protein content remains unchanged.The oxidized form of ribonuclease has no action on the cells.

---

---

Aspirant du Fonds national belge de la Recherche scientifique.     

L'action du 2,4-dichlorophénoxyacétate de sodium sur les végétaux

Zusammenfassung 0,5prozentige Lösungen von 2,4-dichlorophenoxyessigsaurem Natrium verhindern das Keimen vonAgrostemma Githago, Hordeum vulgare undTriticum vulgare. Das Wachstum junger Pflanzen der drei Arten wird durch Verpflanzen auf mit 0,5prozentigen Lösungen dieses Stoffes getränktem Sand gehemmt. Schwächere Lösungen gestatten das Wachstum, es ist aber verlangsamt und die Pflanzen tragen Mißbildungen verschiedener Art, die an die nach Einwirkung von Colchicin und Heteroauxin beschriebenen erinnern. Stark verdünnte Lösungen (5·10^–6) beschleunigen das Wachstum und regen die Wurzelbildung an; diese Wirkung ist beiHordeum vulgare besonders deutlich.     

Propos sur une nouvelle moutarde azotée

Zusammenfassung Es wird vorgeschlagen, N--di-(-chloräthyl)-carbamyl-l-arginin (III) als neues Stickstofflost auf cytostatische Wirkung zu untersuchen; dies in der Erwartung, dass III in Krebszellen in höherem Masse zum cytostatisch wirkenden Di-(-chloräthyl)-amin (V) hydrolysiert wird als in normalen Zellen. Das gleichzeitig freiwerdendel-Arginin sollte die Krebszelle noch empfindlicher gegen V machen.     

Effets comparés de laβ-propiolactone et du formol sur les propriétés inductrices de l'organisateur chez les amphibiens

Summary -propiolactone-treated dorsal lips ofAmbystoma mexicanum are grafted in the blastocele of young gastrulas. The inducing ability of dorsal lips is not altered. These results are compared with the effects of formaldehyde which suppress the inducing ability. An interpretation of these facts is proposed. The cross-linking reactions which occur between formaldehyde and proteins may be important for the suppressing of the inductive ability by this agent.     

Nouvelles considérations sur les moutardes azotées

Summary The cytostatic action of several urethanes-and ureas-nitrogen mustards, as well as that of Endoxan, depends on the appropriate enzymatic activity of the cancerous cell. This enzymatic activity can be considerably stimulated by non-mustard analogues.     

Nouvelles données sur les formules chromosomiques desMuridae

Summary The author has studied 18 species ofMuridae. Only two had previously been investigated. The main results are summarized in a list (see above). Statistically, these observations confirm the statement that more than half of theMuridae have a diploid number between 40 and 56.     

L'action de l'hypoglycémie sur l'électrorétinogramme du lapin

Summary Hypoglycaemia in the rabbit due to an intravenous injection of insulin results in an important diminution of the value of theb wave in the ERG (up till 80%). Nevertheless, this phenomenon does not follow directly upon the lowering of the blood glucose level but takes place, on the average, about 2 h later. This fact is explained by the enormous energy reserves of the retina, the lowering of the ERG taking place only when these reserves are exhausted.

---

---

Travail subventionné par la FondationEmil Barell (Bâle).     

Essais d'élaboration des voies d'approche à la chimiothérapie du cancer. Action sur l'eau d'hydratation des tissus néoplasiques; action sur les protéines

Summary The recent successes in chemotherapy suggest that a solution of the same order should now be possible for cancer. The cause of cancer being still unknown, the therapeutic action aimed at is the creation in the organism of conditions unfavorable for cell multiplication. Certain of the factors essential for cell growth, such as the hydrocarbons, have already been studied in this light. The author has demonstrated the possibility of influencing the high degree of hydration of tumor tissue by the use of substances capable of effecting a homogeneous distribution of the dispersed substances in the aqueous phase. Furthermore, it was proposed to influence the protein repair accompanying cell multiplication by means of substances having an affinity for proteins. This was done to effect a condensation of protein elements before they reach the tumor, thus producing a return to the normal concentration of the free protein fraction, and, at the same time, a decrease in the turn-over of these elements through the tumor. Electrophoretic measurements made with theTiselius apparatus have made it possible to follow protein affinity and to suggest the synthesis of compounds containing quinone and imine groups which may prove valuable in future investigations along these lines.     

L'action du dithizone sur la rétine du lapin Etude électrophysiologique

Summary Dithizone provokes chorio-retinal lesions in the rabbit, visible ophthalmoscopally after 12 h and microscopally after 8 h. The ERG reveals much earlier alterations, theb wave diminishes rapidly and the ERG is abolished in 3 to 4 h. In the cases where no durable lesions are noted, the ERG is nevertheless pathological, theb wave being diminished 40 to 70% of its initial value during the first day, but becoming normal once again even if a permanent diabetes results. These anomalies of the ERG are related to acute hypoglycaemia and enzymatic blockage.

---

---

Travail subventionné par la FondationEmil Barell (Bâle).     

Communications préliminaires sur les chromosomes des Plécoptères

Summary The chromosomal sets of five species ofPerlodidæ (Plecoptera) are given in the present paper. The sexual chromosomes belong to three distinct types:X-O,X ₁-X ₂,X ₁-X ₂-X ₃. The author shows that these three types are likely derived from the most primitive patternX-Y, by translocation and inversion.     

L'électrophorèse sur papier des protéines hydrosolubles du cristallin

Summary By using paper electrophoresis, the authors succeeded in demonstrating different protein fractions in human and animal lenses.Qualitative and quantitative differences were noted in different animals, between the cortical and the nuclear areas of the lens, and also according to age.

---

---

Chargé de Recherches du Fonds national de la Recherche scientifique.     

Présence d'uraninite dans les minéraux accessoires du granite de baveno

Summary Microscopic crystals of uraninite are found in the accessories of the Baveno granite by the nuclear photographic emulsion technique. The uraninite is believed to be a primary mineral of the granite, its concentration in the sample is less than 1 p.p.m. but it contributes about 10% of the total activity.     

Etude histochimique de l'action des rayons X sur les cholinestérases

Summary Using a histochemical method, we have observed the cholinesterase activity in mice after X irradiation. Both types of cholinesterases were examined: AChE (specific ChE) of megacaryocytes of spleen and bone marrow, and AChE of motor endplates; and non-specific ChE of liver, pancreas and prostate. There is no inactivation of AChE even after 5000 r. ChE is also very resistant: activity is slowed down only 12 h or even a few days following irradiation and the inactivation remains slight. We suppose that the great alterations in cellular permeability caused by irradiation are not correlated with these enzymes.     

Action d'un inhibiteur de la carboanhydrase,l'acétazolamide,sur l'excitabilité du cortex,du thalamus et du rhinencéphale

Summary The electrical activity induced by stimulation of the cortex, diencephalon and rhinencephalon was studied in the rabbit under the influence of a carbonic anhydrase inhibitor, acetazolamide or Diamox. A significant decrease of the excitability was found in the diencephalon.The rapidity and the electivity of this action, as well as the blood pH variations simultaneously registered, suggest a specific inhibition of cerebral carbonic anhydrase by Diamox, although a participation of the metabolic acidosis cannot be fully excluded.     

Action d'une irradiation générale sur les échanges d'eau entre le sang et la cavité gastrique pendant l'absorption du glucose

Summary A sublethal dose of X-rays, delivered to guinea-pigs 14 days before a glucose absorption test, alters the pattern of water exchange between the blood and the gastric cavity. The normal dilution, which proves to be a main factor in the regulation of the intestinal absorption of sugar, is no longer achieved.