Synthesis and loss of activity of glucose-6-phosphate dehydrogenase in dividing plant cells

1. Using the technique of density-labelling with deuterium oxide, evidence has been obtained for the de novo synthesis of glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate:NADPH+ 1-oxidoreductase, EC 1.1.1.49), during the culture of synchronously growing plant cells. 2. The entire increase in enzyme activity during the early cell cycles in this material can be accounted for by the appearance of an enzyme species with increased buoyand density. 3. A method is described for resolving overlapping distribution profiles after density centrifugation, which allows estimation of the amount of each species present at different times, and calculation of the loss of activity of the light species present from the start of culture. 4. Loss of activity of glucose-6-phosphate dehydrogenase in normal growing conditions in the presence of 2,4-dichlorophenoxyacetic acid is very much faster than in conditions which do not lead to cell division: in the absence of 2,4-dichlorophenoxyacetic acid, or in the presence of the inhibitor of RNA synthesis, 6-methylpurine.     

Advanced renal cell carcinoma: treatment with xenogeneic immune ribonucleic acid and appropriate surgical resection

Herein we describe the first clinical treatment of renal cell carcinoma in humans with xenogeneic immune ribonucleic acid. Twelve patients with advanced renal cell carcinoma have been treated by appropriate operations to remove tumor bulk followed by specific passive immunotherapy. Xenogeneic specific immune ribonucleic acid was prepared from the spleen of normal sheep that had received 4 weekly injections of a homogenate of renal cell carcinoma. Results indicate that 1) xenogeneic specific immune ribonucleic acid can safely be given to humans without local or systemic toxicity, 2) there is a suggestion of clinical benefit, since only 2 patients have had progression of known metastases during treatment with immune ribonucleic acid and 3) xenogeneic immune ribonucleic acid can enhance the immune response to renal cell carcinoma, as demonstrated by in vitro lymphocytoxicity tests.     

Visual interneurons, sensitive to the size of objects and the direction of their movement in dragonflies of the genus Sympetrum]

Experiments have been made on 4 dragonfly species -- Sympetrum vulgatum, S. flaveolum, S sanguineum, S. danae. A pair of neurons was found in the thoracic ganglia and connectives, which has symmetrical contralateral receptive fields. These neurons are selectively sensitive to swift upward motion of a target of 3--10 degrees in size. This type of response was originally described by Zenkin and Pigarev [1, 2]. The receptive field, 120X25 degrees in size, is oriented horizontally from the medial rim of the eye. The center of sensitivity has the following polar coordinates: 15 degrees laterally from the medial plane and 20 degrees above the equatorial one. The relation of detecting properties of the observed neurones to key stimuli which trigger hunting behaviour is discussed. It is suggested that filtration of single and small optic stimuli by specialized detector neurons results not from the processes in the own receptive field of the neuron, but from the interaction with other neurons which are sensitive to motion of large objects and complex patterns.     

Abnormal or absent beta mRNA in betao Ferrara and gene deletion in delta beta thalassaemia

In patients with betao thalassaemia from Ferrara, beta globin mRNA sequences are either absent or structurally abnormal while in betao thalassaemia in Catania, beta globin mRNA sequences are present. In deltabeta thalassaemia there is a deletion of beta-like globin genes, while in betao Catania DNA, no beta globin gene deletion is detectable.     

Histophysiologic characteristics of the effector innervation of the arteries of the base of the brain during rat ontogenesis

The development of adren- and cholinergic nervous plexuses in the brain base arteries was studied by histochemical methods of Falck and Kelle in animals and fetuses of 10-22 days, newborn rats, animals of 10, 20, 30, 40, 60 and 120 days of life and 1 and 2 years old rats. The cholinergic nerve fibres were first found in the basilar, vertebral and internal carotid arteries on the 15th and 16th days of ontogenesis. Specific fluorescence of adrenergic conductors on the same arteries is revealed somewhat later--from the 17th and 18th days of the intrauterine development. Further formation of the cholin- and adrenergic innervation of the arteries of the Willis' circle goes on synchronously. The number of nerve fibres increases with the growth of the artery diameter. The concentration of catecholamines and the activity of AChE in them gradually increases. The greatest density of nerve fibres per 1 mm2 is determined in 20-day-old rats. The number of cholinergic nerve fibres on the arteries of the brain base is equal to that of adrenergic fibres during the whole period of postnatal ontogenesis. By the 30th day the effector nervous apparatus has a definite structure. In old rats the activity of AChE and the content of catecholamines drop, the amount and concentration of nerve fibres decrease.     

Intellectual deficits after transient tyrosinemia in the term neonate

An analysis was made of the obstetric history of 1,360 patients who were delivered in 1971. It involved 3,185 pregnancies. The aim of the study was to evaluate the risk of spontaneous termination of the pregnancy, worked out from its demographic aspect. Several ideas are worthy of consideration. The risk of spontaneous intra-uterine death is cumulative, sharply increased by a repetition of such cessation of pregnancy. The same patients often undergo intentional abortion repeatedly. The respective risks of spontaneous and provoked interruption of pregnancy have been studied in greater detail as a function of parity.     

The cell surface of Trypanosoma musculi bloodstream forms. II. Lectin and immunologic studies

Report is given on a metabolic investigation with non-radioactive and 14C-labelled methiothepin(1-[10',11'-dihydro-8'-(methylthio)-dibenzo mean value of b,f thiepin-10'yl]-4-methyl-piperazine) in rat, dog, and man. After i.p. and oral administration of the drug to the rat, the metabolites of methiothepin were excreted fecally. In the same species, a considerable biliary secretion of the compounds has been demonstrated. In dog and in man, excreted metabolites have been found both in urine and feces after oral application of the drug. The biotransformation of methiothepin within the species investigated proceeds via hydroxylation, sulfoxidation, O-methylation, N-demethylation, N-oxidation and formation of conjugates. The large number of metabolites is due to the various sites of action within the molecule, that are accessible to in vivo oxidation. Of a large number of isolated positionally isomeric compounds, merely the basal structures could be clarified. Possibly the mode of biotransformation to which methiothepin is subjected in the organism, proves determinant for the way of excretion. In the rat, all metabolites are hydroxylated and reach the intestinal tract as conjugates with the bile. In dog and man, however, non-hydroxylated, sulfoxidized metabolites were likewise found, which were excreted mainly renally in both species.     

Morphological and physiological characteristics of Gemmiger formicilis isolated from chicken ceca

Morphological and physiological studies were made on chicken cecal isolates of the strictly anaerobic bacterial species Gemmiger formicilis. Structural features (phase-contrast and electron microscopy) of these microorganisms indicate they (i) are highly pleomorphic, (ii) possess a trilaminar cell wall like gram-negative bacteria, (iii) exhibit an unusual growth process characterized by polar swelling (resembling budding bacteria), and (iv) grow into elongated cells when exposed to a subinhibitory concentration of penicillin. The morphological data presented suggest that this species has a rod-shaped structure. These bacteria ferment a variety of sugars to produce formic, butyric, and lactic acids. There appear to be two groups of Gemmiger, one producing primarily lactate and the other producing formate as major fermentation metabolites. Growth of six strains in a basal medium, consisting of Trypticase, minerals, carbohydrate, Na2CO3 buffer, and cysteine as reducing agent, was stimulated by rumen fluid and yeast extract. Volatile fatty acids partially replaced the requirement for rumen fluid with some strains. Single deletions of vitamins (from a defined vitamin mixture) indicated that pantothenate, riboflavin, and thiamine were highly stimulatory to growth of the organism in a medium containing rumen fluid and Trypticase as source of vitamins. Other vitamin requirements were not studied.