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Lipopolysaccharide (LPS) prepared from Vibrio choleraeand a non-agglutinable (NAG; not agglutinable with O-group I serum according to Gardner and Venkatraman [13]) vibrio strain, isolated from a patient with cholera-like clinical symptoms, have been compared with respect to their chemical composition and immunological behavior. In addition to a significant difference in the chemical composition between the two lipopolysaccharides, the LPS from V. cholerae, unlike that from the NAG vibrio, requires prior treatment with alkali for it to be an effective antigen in the indirect hemagglutination test with sheep cells. It has been suggested that the alkali acts by removing excess O-acetyl group from LPS of agglutinable vibrios. LPS from the NAG vibrio consistently showed a lower antibody response in rabbits in terms of agglutinin and vibriocidal titer. Also, the class of agglutinin antibody elicited by LPS of the NAG vibrio was predominantly immunoglobin M, and that from V. choleraewas immunoglobulin G under comparable conditions.

DNA sequences in Neurospora crassathat code for ribosomal RNA have been isolated in a highly purified state by DNA-RNA hybridization. About 100 separate ribosomal RNA genes exist in each nucleus. These genes are composed of repeated sequences that are present about 100 times per nucleus. The individual members of this group of DNA sequences are essentially identical.

1In cats anaesthetized with chloralose, repeated injections of 20 μgouabain were made either into the cerebral ventricles, or into the ventromedial nucleus of the hypothalamus (VMH), or intravenously whilst the electrocardiogram, arterial blood pressure and respiration were recorded.2The injections produced cardiac arrhythmias preceded by sinus bradycardia, variable changes in arterial blood pressure and respiratory depression. Death occurred either from ventricular fibrillation or from cardiac arrest.3The arrhythmias which occurred after the injections into the cerebral ventricles were not peripheral effects produced after absorption of the ouabain into the blood stream, because with intravenous injections larger amounts were required to produce the arrhythmias and to cause death than with intraventricular injections. The arrhythmias which resulted in death were due to an action on the VMH. With microinjections of ouabain into this region of the brain death occurred earlier and after smaller doses than after intraventricular injections.4While sinus bradycardia was abolished by bilateral vagotomy other cardiac arrhythmias were prevented by acute cardiac sympathectomy and cervical cord transection. Thus both the sympathetic and parasympathetic nervous systems appear to be involved in the production of these arrhythmias.5Since some of the cardiac arrhythmias obtained with ouabain in anaesthetized cats resemble the cardiotoxic effects seen in clinical practice during treatment with digitalis glycosides it is concluded that these effects, too, are, at least in part, central in origin, caused by an action on the VMH and mediated mainly via the sympathetic nervous system.

Beim Zerfall von Na24entstehen angeregte niederenergetische Mg24-Rückstoßkerne mit einer kinetischen Energie bis zu ca. 170 eV.

Study of the antimicrobial spectrum of valinomycin revealed that, in addition to the gram-positive bacteria reported in literature, Streptococcus pyogenesand Clostridium sporogenesare also susceptible to this antibiotic. The minimal inhibitory concentrations (MIC) of the antibiotic for S. pyogenesgrown aerobically and anaerobically did not differ markedly, negating the hypothesis that oxidative phosphorylation is involved in the mechanism of action of this antibiotic. This conclusion is further strengthened by the inhibition of growth of C. sporogenes, an obligate anaerobe. In a medium with a low K+concentration, the MIC for S. pyogeneswas 0.02 μg/ml, the lowest ever recorded for this antibiotic. The inhibition of growth of S. pyogenesand C. sporogeneswas readily reversed by addition of K+to the medium, indicating a compensation for net efflux of K+from the cells when the transmembrane potential reached equilibrium. In contrast to these bacteria, Bacillus subtiliswas less susceptible to the antibiotic when the potassium concentration of the medium was low. The addition of potassium in the presence of valinomycin increased the inhibition of growth, which appears to result from dissipation of metabolic energy as in the mitochondrial system.

Different preparations of chromatin isolated from mycelia of Neurospora crassa were analyzed for DNA-associated RNA and proteins. The UV absorption spectra, the ultrastructure of chromatin, and the amino acid composition of the acid-extractable proteins were studied. The protein:DNA ratios range from 1.5 to 2.8; the RNA:DNA ratios range from 0.5 to 1.24. UV absorption shows a macimum at 259 mµ and a minimum at 238–239 mµ. The E280/E260 ranges from 0.59 to 0.70. Electron microscopy reveals a fibrous structure with individual fibers of 120–150 A average diameter. Attempts were made to study the protein by polyacrylamide gel electrophoresis and amino acid analysis. The results indicate that Neurospora chromatin does not contain basic proteins comparable to calf thymus histone. The ratios of basic to acidic amino acids range from 0.93 to 1.19. On electrophoresis, no bands are seen whose positions correspond to those of histones. Staining for basic proteins with fast green or eosin Y at pH 8.2 also shows a negative reaction, suggesting the absence of histones.

Yorke and Adams1have found that 5 per cent emetine fails to kill the cysts of Entamoeba histolytica in 30 min in vitro. This communication deals with the effect of emetine in preventing excystment of Schizopyrenus russelli and the cysticidal action of the drug in conjunction with sodium lauryl sulphate.

SEVERAL substances like strychnine, adrenaline and curare alkaloids are known to set free histamine from skeletal muscle. The release of histamine from rat diaphragm by ammonia1and B-tubo-curarine chloride2has recently been reported. Feldberg and Kellaway3have shown that snake poisons liberate histamine from the perfused lungs of guinea pigs and cats. The experiments described here demonstrate that cobra (Naia naia) venom is a potent liberator of histamine from striated muscle of the rat.

THE structure of the molybdenite crystal has been determined by Pauling and Dickinson1and Hassel2. They found that the molybdenum and sulphur atoms in it are arranged in separate layers perpendicular to the c-axis. Each layer of molybdenum atoms has two layers of sulphur atoms on opposite sides of it. The whole structure is then built up by the repetition of composite layers each of which is formed by a molybdenum layer sandwiched between two sulphur layers. The excellent cleavage in a plane parallel to the layers themselves may be regarded as a natural consequence of the large distance between these successive composite layers. In layer structures of this type, it seems that the major portion of the primary valencies is exercised within the layers themselves, and only secondary forces hold the layers together to form the crystal lattice.

RECENT experimental studies1on the compressibility of liquids and liquid-mixtures indicated the existence of a connexion between the compressibility and viscosity. The usual equations representing viscosity – temperature relation of liquids do not, in any form, contain the compressibility function. After trial, it was observed that the viscosity of liquids could be well represented by an equation of the form : () where A and B are constants, and β is the adiabatic compressibility. β, at any temperature, was calculated from the supersonic velocity and the density of the liquid for that temperature.

UREA STIBAMINE, introduced by Brahmachari1in 1922 and widely employed in the treatment of kalaazar in India and elsewhere, still remains a compound with no definitely known and agreed chemical formula. It was originally reported to be a substance composed of urea and para-aminophenylstibinic acid with the empirical formula, C7H12O4N3Sb. Later it was suggested that the compound was identical with ammonium-para-carbamidophenylstibinate, NH2.CO. NH.C6H4.SbO(OH).ONH42. Ghosh et al.3and Gray et al.4gave definite evidence that urea stibamine was not a single substance of definite composition and the latter group of workers showed that the ‘effective active principle’ was a di-substituted urea, S-diphenyl-carbamide-4:4 distibinic acid. The antimony content of various commercial samples was shown by Ghosh et al. to vary between 20 and 43 per cent, while Gray et al. reported a comparatively smaller range of variation in antimony content from 44.19 to 48.6 per cent. Brahmachari5appeared to have accepted the results of Gray et al. in this regard, and emphasized that the divergent results obtained by different investigators were due to different brands of “so-called urea stibamine”, not conforming to his original specifications, being put on the Indian market.

THE discovery of human remains from a Late Stone Age site in the village of Sarai Nahar Rai in Uttar Pradesh has provided the earliest available skeletal evidence of man in the Indian subcontinent. This northern Indian site, which is in the district of Pratapgarh, lies about 38 km north of Allahabad city and 33 km south-west of Pratapgarh town, connected by road. It covers about 2,700 m2(about lat. 25° 48′ north and long. 81° 50′ east) and is about 9 km west of Bishnathganj Railway Station on the Allahabad-Fyzabad line of the Northern Railway. It was discovered in 1968. The eastern sector of the site—about 600 m2—had been badly eroded and there was visible evidence of a cluster of human graves, the only such example to have been reported from the plain of the Ganga.

PREVIOUS measurements of the heat produced by ultrasonic waves in a trap vessel1gave results that differed from those obtained by other methods2for the absorption coefficients in carbon disulphide, xylene and kerosene, the last two appear to have abnormally high values, particularly from measurements with narrow trap vessels. The results were confirmed with trap vessels made of plaster of Paris, with windows of thin paper or ‘Cellophane’ in place of mica. The abnormal behaviour cannot, therefore, be attributed to any electrical effect in the metallic core of the trap, or to the mica windows.

Spores of race 2 but not of race 1 of Colletotrichum lagenariumare ingested by myxamoebas of strain NE-30 of the slime mold Acrasis rosea.Sporulating colonies of three heterocaryons of C. lagenariuminvolving auxotrophic strains with different color markers of races 1 and 2 were inoculated with myxamoebas. Although spores of race 1 produced on homocaryons were not ingested by the myxamoebas, they were ingested when produced on heterocaryons involving race 2. Spores from sectors of the heterocaryons yielded colonies of race 1; spores from these colonies were not ingested by the myxamoebas.

FOR the past two years1, it has been clear that the development of a new and convenient method for the synthesis of the berberine alkaloids hinged on the preparation of 6,7-methylenedioxy (I)- and 6,7-dimethoxyisoquinoline aldehydes (II). The use of the first of these in the synthesis of tetrahydroberberine and related alkaloids has been reported2. The present communication describes the preparation and use of the dimethoxyisoquinoline aldehyde (II).

‘ANTRYCIDE’, a trypanocidal drug which has been reported to be inactive in vitro, exerts marked chemotherapeutic activity in vivo1. This difference in activity of ‘Antrycide’ in vitro and in vivo may possibly be due to the drug being converted to a more active metabolic degradation product than the parent drug, or activated in vivo through the intervention of the reticulo-endothelial system. The first of these possibilities cannot be excluded in the present state of knowledge, as very little is known about the metabolic degradation products of ‘Antrycide’. This communication presents evidence to support the latter view that the reticulo-endothelial system plays an important part in the chemotherapeutic activity of ‘Antrycide’ (methylsulphate salt) against T. evansi in rats. The strain of T. evansi is of equine origin, isolated at the Indian Veterinary Research Institute in 1945, and being maintained through blood passages in rats.

ULTRASONIC absorption in some liquids has been measured by the method of heat development. The apparatus and its working was designed in such a way as to make it free from error due to the variation of generator power and also due to reflexion. A 3 Mc./s., 100 W. quartz generator produced the beam in liquid kerosine, contained in a vessel with cork paddings at the ends. In a small double-walled metallic vessel with asbestos packing, having a suitable coat of cement, two mica windows of 0.002 cm. thickness were fitted to allow the beam to pass in and out again after absorption. Two such vessels were made with exactly similar windows and different separations; the separations of windows were 3.6 cm. and 4.6 cm. Arrangements were made to place the front windows in the same relative position with respect to the quartz. The rise in temperature in these fairly non-conducting trap vessels, with different liquids, was measured in the steady condition. The electrical wattage to produce the same steady difference of temperature between the trap vessel and the outer kerosine was determined by a separate experiment. The temperature of the kerosine in the outer vessel was controlled by running ice-cold water around the vessel.

FRANCK and his co-workers have shown that the vapours of alkali halides show a continuous absorption spectrum beginning from a long waverlength limit and extending towards the ultra-violet. He interpreted the absorption spectrum as follows : if we take a substance like sodium chloride the valency electron of Na in the normal state may be supposed to pass over completely to Cl and the combination consists of Na+Cl-. Such a combination is called ionic. When light falls on sodium chloride vapour, the electron passes over from Cl-to Na+, the molecule thus splitting into Na and Cl. Franck obtains the heat of formation Q of NaCl from atomic Na and atomic Cl with the aid of a Born cycle and finds that Q =N hν where ν = frequency of the beginning of continuous absorption.