Pectin synthesis during the wall regeneration of plasmolysed tobacco leaf cells. 1. Discs of tobacco leaf lamina were floated on media containing D-[U-14C]glucose. Glucose uptake was mainly through the cut edges, and diffusion through the veins and intracellular spaces was slow. 2. Radioactivity was detected in all polysaccharide fractions extracted from the discs, including those associated with the wall. 3. Plasmolysis in sorbitol or KCL decreased the incorporation of radioactive material into all fractions. 4. Incorporation of arabinose into pectins was increased or unaffected by plasmolysis, but the incorporations of other sugars were decreased. Removal of the lower epidermis did not affect this result. 5. Seperate mechanisms for arabinan and polygalacturonorhamman syntheses must exist, and these must differ in their responses to the physiochemical, structural and organizational changes that accompany plasmolysis.


Studies on the role of insulin in the regulation of glyceride synthesis in rat epididymal adipose tissue. 1. When rat isolated fat-cells were incubated with fructose and palmitate, insulin significantly stimulated glyceride synthesis as measured by either [14C]fructose incorporation into the glycerol moiety or of [3H]palmitate incorporation into the acyl moiety of tissue glycerides. Under certain conditions the effect of insulin on glyceride synthesis was greater than the effect of insulin on fructose uptake. 2. In the presence of palmitate, insulin slightly stimulated (a) [14C]pyruvate incorporation into glyceride glycerol of fat-cells and (b) 3H2O incorporation into glyceride glycerol of incubated fat-pads. 3. At low extracellular total concentrations of fatty acids (in the presence of albumin), insulin stimulated [14C]fructose, [14C]pyruvate and 3H2O incorporation into fat-cell fatty acids. Increasing the extracellular fatty acid concentration greatly inhibited fatty acid synthesis from these precursors and also greatly decreased the extent of apparent stimulation of fatty acid synthesis by insulin. 4. These results are discussed in relation to the suggestion [A.P. Halestrap & R.M. Denton (1974) Biochem. J. 142, 365-377] that the tissue may contain a specific acyl-binding protein which is subject to regulation. It is suggested that an insulin-sensitive enzyme component of the glyceride-synthesis process may play such a role.


Synthesis of proline and hydroxyproline in human lung (WI-38) fibroblasts. Human lung fibroblasts (WI-38) in late exponential phase of growth, in stationary phase after confluency was reached, and at high or low number of population doublings were used to investigate the synthesis of proline and hydroxyproline from glutamate or arginine. Glutamate was from two to five times as effective a precursor as arginine; glutamine did not seem to be involved in these metabolic pathways. Accumulation of protein-bound hydroxyproline in cell layers was observed only after confluency. Confluent cells synthesized more proline from glutamate than did cells in late exponential growth. Conversion of glutamate into intracellular free proline was conducted also to a greater extent in confluent cells at a high number of population doublings. Conversion of glutamate into proline or hydroxyproline in cell-layer protein was not affected significantly by the number of population doublings. Less total protein as well as less hydroxyproline accumulated with cells at a high number of population doublings.


Regulation of rat liver tryptophan pyrrolase by its cofactor haem: Experiments with haematin and 5-aminolaevulinate and comparison with the substrate and hormonal mechanisms. 1. The administration of haematin or 5-aminolaevulinate to rat enhances the activity of liver tryptophan pyrrolase; both endogenous and newly formed apoenzymes become strongly haem-saturated. Haem activation does not stabilize tryptophan pyrrolase. 2. Actinomycin D, puromycin or cycloheximide prevent the activation of the enzyme by 5-aminolaevulinate but not that by haematin. The latter is inhibited by haem-destroying porphyrogens. 3. The combined injection of either haematin or 5-aminolaevulinate with cortisol does not produce an additive effect, whereas potentation is observed when tryptophan is jointly given with either the cofactor or the haem precursor. 4. Further experiments on the substrate (tryptophan) mechanism of pyrrolase regulation are reported, and a comparison between this and the cofactor and hormonal mechanisms is made. 5. It is suggested that the substrate mechanism may also involve increased haem synthesis. 6. The role of tryptophan pyrrolase in the utilization of liver haem, and as a possible model for the exacerbation by drugs of human hepatic porphyrias, is discussed.


Intermolecular transacylation of phosphatidylethanolamine by a Butyrivibrio sp. 1. Washed cells and supernatant from a culture of a Butyrivibrio sp. carry out the intermolecular transacylation reaction 2 phosphatidylethanolamine leads to N-acylphosphatidyl-ethanolamine+lysophosphatidylethanolamine. 2. Washed cells can catalyse the intramolecular transacylation of N-(acyl)glycerylphosphorylethanolamine to lysophosphatidylethanolamine; the culture supernatant is largely devoid of activity.


The reversibility of active sulphate transport in membrane vesicles of Paracoccus denitrificans. An uncoupler-sensitive active transport of sulphate into membrane vesicles prepared from the plasma membrane of Paracoccus denitrificans (previously Micrococcus denitrificans) can be driven by respiration or by a trans-membrane pH gradient (alkaline inside) generated by the addition either of KCL ( in the presence of nigericin) or of NH4CL. Valinomycin does not substitute for nigericin. Respiration-driven transport is observed in right-side-out vesicles but not in inside-out vesicles, whereas transport driven by the addition of KCL (in the presence of nigericin) or of NH4CL is observed in both types of membrane vesicle. The active transport of sulphate into these vesicles is shown to be carrier-mediated by its sensitivity to thiol-group reagents. It is proposed that the sulphate carrier in the plasma membrane of P. denitrificans operates by a mechanism of electroneutral proton symport, and is capable of actively transporting sulphate in either direction across the plasma membrane, but that in whole cells respiration-driven proton expulsion drives the accumulative uptake of sulphate.


Ornithine decarboxylase activity and: [125I]iododeoxyuridine incorporation in rat prostate. The relationship between ornithine decarboxylase activity and [125I]iododexyuridine incorporation was studied in prostates from castrated rats (aged 5, 26 and 80 weeks) injected daily with testosterone for up to 10 days. The results suggest that ornithine decarboxylase activity is a parameter of secretory activity, rather than growth, in the ventral prostate. In the dorsolateral prostate, ornithine decarboxylase activity tends to parallel [125I]iododeoxyuridine incorporation.


An 18O double-labelling study of haemoglobin catabolism in the rat. The degradation of haemoglobin to bilirubin in the rat was investigated by 18O labelling of the molecular oxygen consumed by the animal. The oxygen atoms incorporated into bilirubin were derived from two different oxygen molecules. Implications of this finding for the mechanism of haem catabolism in vivo are discussed; both verdohaem and a dioxygen-bridged compound appear to be excluded at intermediates.


The autotrophic growth of Micrococcus denitrificans on Methanol. Ribulose bisphosphate carboxylase is present at a high specific activity in extracts of methanol-grown Microccus denitrificans. Enzymic and physiological evidence indicates that, during growth on methanol, the ribulose bisphosphate cycle is the route of carbon assimilation.


Ribosome function in livers of porphyric mice. 1. A porphyrinogenic drug, 3,5-diethoxycarbonyl-1,4-dihydrocollidine, caused a decrease in the proportion of single ("run off") ribosomes, and an increase in the number of polyribosomes, in the livers of treated animals. 2. No change could be detected in the distribution of amino acid incorporation among hepatic polyribosomes.


A theoretical approach to the binding of amphipathic molecules to globular proteins. 1. A theory based on a multiple equilibrium model with stoicheiometric binding constants has been formulated. It is applicable to the interaction of amphipathic molecules with charged macromolecules. 2. The theory has been applied to the binding of sodium n-dodecyl sulphate to ribonuclease A, beta-lactoglobulin and bovine serum albumin. 3. Over the ranges of surfactant concentration where binding is non-co-operative and co-operative, the experimental data can be satisfactorily fitted with energy and co-operatively parameters which are of comparable magnitude for the three globular proteins. 4. The results imply that the energy of interaction of sodium n-dodecyl sulphate with the proteins is equivalent to the formation of approximately four CH2 hydrophobic bonds.


Some enzymes present in the walls of mesophyll cells of tobacco leaves. Cell-wall enzymes were assayed by the difference between enzyme activities in the whole cell and the protoplast. Both peroxidase (85.2%) and acid phosphatase (21.9%) were located in the wall. However, malate dehydrogenase was found only in the protoplast. A study of the time-course of the release of peroxidase and malate dehydrogenase into the incubation medium from cells either treated with cellulase or untreated, also indicated that peroxidase and not malate dehydrogenase was located in the wall. Only two anodic isoenzymes of peroxidase were present in the cell wall. These were more negatively charged than those of horseradish peroxidase.


The purification and properties of a beta-N-acetylhexosaminidase from Trichomonas foetus. A beta-N-acetylhexosaminidase was purified 800-fold from extracts of Trichomonas foetus by affinity chromatography on a column of N-(epsilon-aminohexanoyl)-2-acetamido-2-deoxy-beta-D-glucopyranosylamine bound to CNBr-activated Sepharose. The enzyme has a dual specificity for the p-nitrophenyl beta-D-glycosides of N-acetylglucosamine and N-acetyl-galactosamine. The parent sugars are both competitive inhibitors. The enzyme has a mol. wt. approx. 150000 and a pH optimum of 6.2. It is suggested that the same active site catalyses both activities and that no part is played by the 4-hydroxyl group in substrate binding, but it is involved in determining the catalytic rate.


The mechanism of polyribosome disaggregation in brain tissue by phenylalanine. The injection of neonatal mice with phenylalanine resulted in a rapid decrease in brain polyribosomes and a concomitant increase in monomeric ribosomes. Animals of 1-16 days of age were equally affected by phenylalanine, although the brain polyribosomes of 60-day-old mice were relatively resistant to the effects of phenylalanine. The population of free polyribosomes appeared to be more sensitive to phenylalanine treatment than bound polyribosomes, which were somewhat more resistant to disruption by high concentrations of the amino acid. The effects of phenylalanine were more pronounced with polyribosomes in the cerebral cortex than with those in the cerebellar tissue. The mechanism of polyribosome disruption was shown to be independent of hydrolysis mediated by ribonuclease. Virtually all of the monomeric ribosomes that resulted from phenylalanine treatment were shown to be inactive with regard to endogenous protein synthesis and were present in the cell cytoplasm as vacant couples. These ribosomes were readily dissociated by treatment with 0.5 M-KCl and subsequent ultracentrifugation. These results are discussed in the light of the possibility that high concentrations of phenylalanine disrupt brain protein synthesis by a molecular mechanism that is associated with initiation events.


Purification of insect myosin and alpha-actinin. A method is described for preparing insect myosin, tropomyosin and alpha-actinin. The amino acid compositions of the myosin and alpha-actinin are given, and some of the properties of the purified proteins are discussed.


A quenched-flow study of the reaction catalysed by creatine kinase. The reaction catalysed by creatine kinase was studied in both directions by quenched-flow techniques to follow the initial product formation in the millisecond range. In both directions the amount of product formed increases linearly with time, and the turnover number corresponds to the steady-state value. Extrapolation to zero time indicates the absence of either a large transient phase or a large lag phase in both directions. This indicates that the actual chemical reaction is rate-limiting, and that all possible isomerizations before or after the chemical step must be much more rapid.


The primary structure of troponin T and the interaction with tropomyosin. 1. Eight peptides were separated from the CNBr digest of troponin T from rabbit white skeletal muscle and characterized. 2. By study of the amino acid sequence of the methionine-containing peptides isolated after chymotryptic and tryptic digestion and of the N- and C-terminals of the CNBr peptides, six of the latter were shown to be arranged in the sequence CNB1-CNB2-CNB5-CNB6-CNB8-CNB7. The other two peptides, CNB1' and CNB3, have been shown to be partial digestion products. 3. The CNBr peptides CNB1' and CNB2 contained a common sequence and were the only peptides in CNBr digests of troponin T that formed a complex with tropomyosin as judged by viscometric and electrophoretic studies. 4. It is concluded that tropomyosin interacts with the N-terminal half of the troponin T molecule approximately in the region lying between residues 70 and 160. 5. Electrophoretic evidence indicates that tropomyosin and troponin C interact with troponin T. 6. None of the major CNBr peptides of troponin T isolated formed a complex with troponin C on electrophoresis at pH 8.6.


Oplophorus oxyluciferin and a model luciferin compound biologically active with Oplophorus luciferase. The luciferin of the bioluminescent decapod shrimp, Oplophorus gracilorostris, was purified and studied with respect to u.v. spectrum, fluorescence spectrum, mass spectrum and luminescent cross-reaction with the enzyme luciferase of the bioluminescent ostracod, Cypridina hilgendorfii. On the basis of these results, an empirical formula C10H13N3O3 and an imidazo [1,2-a]pyrazin-3-one structure are proposed for luciferin. Of three model luciferin compounds, 3-hydroxy-2-methylimidazo[1,2-a]pyridine is biologically active with both Oplophorus and Cypridina luciferase, indicating that a pyrazine structure is not essential for biological activity with Cypridina luciferase.


Phosphorylation of the light-chain components of myosin from cardiac and red skeletal muscles. 1. The light-chain components of myosin from cardiac muscle (19000 and 27000 daltons) and of rabbit soleus and crureus muscles (19000, 27000 and 29000 daltons) were characterized. 2. The 19000-dalton components in carciac- and red-skeletal-muscle myosins were spontaneously modified to a component of slightly higher net negative charge. 3. The 19000-dalton component in cardiac and red skeletal muscles and their modified forms were phosphorylated by myosin light-chain kinase. 4. Evidence was obtained for the presence of myosin light-chain kinase in cardiac and red skeletal muscles. 5. Myosin light-chain kinase catalysed the phosphorylation of the whole light-chain fraction from white and red skeletal muscle at similar rates. The light-chain fraction of cardiac-muscle myosin was phosphorylated at a significantly lower rate. 6. The light-chain components of cardiac-muscle myosin and their phosphorylated froms were separated by ion-exchange chromatography and their amino acid compositions determined.


The androgenic regulation of the activities of enzymes engaged in the synthesis of deoxyribonucleic acid in rat ventral prostate gland. The restoration of mitosis and growth of the prostate gland of castrated animals by androgens provides a favourable experimental system for studying the hormonal regulation of enzymes engaged in DNA replication. 2. Many DNA polymerase activities were identified in the prostate gland, but only a 9S form with a particular preference for denatured DNA as template was conspicuously enhanced by androgenic stimulation. 3. Thymidine kinase also provided a sensitive indicator of the hormonal regulation of DNA replication, and on electrophoretic criteria, one discrete form of the enzyme appeared precisely with the onset of mitoris. 4. Evidence is presented to support the view that DNA ligase activity is intimately associated in the process of DNA replication in the prostate gland. 5. A spectrum of deoxyribonuclease activities is present in the prostate gland, but only one form (pI7.0) can safely be said to be implicated in the process of DNA replication. 6. Androgenic stimulation of the prostate gland leads to the appearance of a component capable of denaturing or unwinding prostate DNA. This component is seemingly distinct from RNA or DNA polymerase activities on the basis of several distince physicochemical characteristics. 7. The conspicuous feature of all the changes in enzyme activities evoked by androgens in the prostate gland is their acute tissue- and steroid-specificity. Such changes could not be mimicked in liver or spleen and the regulatory role of androgens could not be simulated by other classes of steroid hormones. Particularly on the basis of studies with the anti-androgen cyproterone acetate, it is concluded that the changes are initially mediated by the androgen-receptor system and the high-affinity binding of 5alpha-dihydrotestosterone in the prostate gland. 8. The results are discussed in the context of the mechanism of action of androgens.


Relationships between the exchange of calcium and phosphate in isolated fat-cells. The uptake and the washout of 45Ca2+ and 32Pi is described in free fat-cells and whole epididymal fat-pads from fed rats. 2. In isolated fat-cells, the uptake of 45Ca2+ proceeds with an initial rapid phase of about 1 min duration, followed by a slower subsequent accumulation. In contrast with the rapid phase, the slow phase is inhibited by 2,4-dinitrophenol, warfarin, oligomycin and verapamil, shows saturation, and presumably represents transport across the plasma membrane. 3. The washout of 45Ca2+ from preloaded cells consists of a rapid (1 min) initial phase and a slow phase which is non-monoexponential, suggesting that the radioactive isotope is released from several cellular pools. 4. When Pi is omitted from the incubation medium, the slow phase of 45Ca uptake is almost abolished, and the washout of 45Ca from preloaded fat-cells is markedly accelerated. At elevated extracellular concentrations of Pi (2,4-6.2mM), the uptake of 45Ca is stimulated by 2-10-fold, and the release of the radioactive isotope from preloaded cells is inhibited. In whole epididymal fat-pads, variations in the extracellular concentration of Pi have no detectable effect on the uptake or the washout of 45Ca. 5. In isolated fat-cells, the accumulation of 32Pi is inhibited by 2,4-dinitrophenol or the omission of glucose from the incubation medium. In a Ca2+-depleted buffer, the uptake of 32Pi is diminished, and hyperosmolarity, which stimulates 45Ca uptake, also accelerates the accumulation of 32Pi. 6. It is concluded that in free fat-cells, the uptake and release of Ca2+ and Pi take place by closely interrelated processes, which are dependent on mitochondrial energy production.


Milk glucose as an index of the intracellular glucose concentration of rat mammary gland. The aqueous glucose concentration of rat milk is about 0.29mM, apparently unmodified by prolonged storage in the gland. Infused 3-0-methylglucose reaches a milk concentration similar to its measured mammary intracellular concentration. Milk glucose may therefore reflect its intracellular concentration in the mammary secretory cell.


Purification and characterization of guinea-pig intestinal brush borders. The purification of guinea-pig intestinal brush borders by a rapid sucrose-gradient-centrifugation step is reported. A 29-fold increase in the maltase/DNA quotient indicates considerable purification of the brush borders from nuclei. The biological activity of the brush borders was well preserved, as demonstrated by a high recovery of human gastric-juice-mediated uptake of 57Co-labelled vitamin B-12; homogeneity and purity were confirmed by scanning electron microscopy. Both the morphological appearance and biological activity were unchanged after prolonged storage in glycerol.


Induced transcription-dependent synthesis of mitochondrial reduced nicotinamide-adenine dinucleotide dehydrogenase in Drosophila. Salivary glands of Drosophila hydei recovering from an anaerobic treatment show a significant increase in apparent Vmax of mitochondrial NADH dehydrogenase. This increase in Vmax is based on an increase in enzyme molecules resulting from synthesis de novo in the cytoplasm, as indicated by the inhibition by cycloheximide of both the increase in apparent Vmax and the increase in amino acid incorporation into enzyme fractions. The increase in enzyme activity is also inhibited by actinomycin D, which is in support of previous data indicating a casual relationship between transcription in puff 4-81B in the polytene chromosomes and an increase in apparent Vmax of the enzyme. Gel electrophoresis of mitochondrial protein extracts revealed three protein fractions with NADH dehydrogenase activity. All three fractions showed increased activity as well as increased amino acid labelling in glands recovering from anaerobiosis compared with control glands. The data suggest that the increase in mitochondrial NADH dehydrogenase activity in salivary glands recovering from an anaerobic treatment depends on increased gene transcription.


The contents of adenine nucleotides, phosphagens and some glycolytic intermediates in resting muscles from vertebrates and invertebrates. The lowest contents of ATP and the lowest ATP/AMP concentration ratios are observed in the molluscan muscles that have very low rates of energy expenditure during contraction. The highest contents of ATP are observed in the extremely aerobic insect flight muscle and the extremely anaerobic pectoral muscle of the pheasant and domestic fowl. In general, the lowest ATP/AMP concentration ratios are observed for muscle in which the variation in the rate of energy utilization is small (e.g. some molluscan muscles, heart muscle); the highest ratios are observed in muscles in which this variation is large (lobster abdominal muscle, pheasant pectoral muscle, some insect flight muscles). This finding is consistent with the proposed role of AMP and the adenylate kinase reaction in the regulation of glycolysis. However, in the flight muscle of the honey-bee the ATP/AMP ratio is very low, so that glycolysis may be regulated by factors other than the variation in AMP concentration. The variation in the contents of arginine phosphate in muscle from the invertebrates is much larger than the variation in creatine phosphate in muscle from the vertebrates. The contents of hexose monophosphates and pyruvate are, in general, higher in the muscles of vertebrates than in those of the invertebrates. The contents of phosphoenolpyruvate are similar in all the muscles investigated, except for the honey-bee in which it is about 4-10-fold higher. The mass-action ratios for the reactions catalysed by phosphoglucoisomerase and adenylate kinase are very similar to the equilibrium constants for these reactions. Further, the variation in the mass-action ratios between muscles is small. It is concluded that these enzymes catalyse reactions close to equilibrium. However, the mass-action ratios for the reactions catalysed by phosphofructokinase and pyruvate kinase are much smaller than the equilibrium constants. The variation in the ratios between different muscles is large. It is concluded that these enzymes catalyse nonequilibrium reactions. Since the variation in the mass-action ratios for the reactions catalysed by the phosphagen kinases (i.e. creatine and arginine phosphokinases) is small, it is suggested that these reactions are close to equilibrium.


The thermochemical characterization of sodium dithionite, flavin mononucleotide, flavin-adenine dinucleotide and methyl and benzyl viologens as low-potential reductants for biological systems. The heat of reaction (deltaH) of Fe(CN)63-, Methyl Viologen, FMN and FAD with S2O42- in aqueous buffer solutions was measured calorimetrically. In addition deltaH values for reduction of Fe(CN)63-, FMN and FAD by reduced Methyl Viologen were determined. The resulting calorimetric data and corresponding E0 values were combined to yield thermodynamic data for these simple reducing agents in a form useful for applications to biological reactions. Thermodynamic data for the reduction of spinach ferredoxin are also presented.


Determination of the amount of small messenger ribonucleic acid-containing particles free in liver cytoplasm. To assess the contribution made by mRNA-containing particles to the heterogeneity previously observed among rat liver 40S ribonucleoprotein particles, the amount of poly(A)-containing RNA in subribosomal particles was determined. RNA was labelled with orotate in vivo for 24h and then for 50min. Poly(A)-containing RNA was trapped on filters impregnated with poly(U). Very little poly(A)-containing RNA was found in conventionally prepared ribonucleoprotein particles after fractionation in sucrose. However, after preparation of ribonucleoprotein particles by sedimentation through 1 M-sucrose in the presence of 0.15M-KCl or by precipitation with Mg2+ as described by Leitin & Lerman [(1969) Biokhimiya 34, 839-849], amounts of poly(A)-containing RNA were similar to amounts of mRNA found by other workers in total ribonucleoprotein particles. Even in such preparations, less than 5% of the total rapidly labelled RNA in native subribosomal-particle fractions was mRNA. It seems that mRNA-containing particles make up only a very small part of the population of subribosomal particles in liver.


The induction of enzyme activity in the endosperm of germinating castor-bean seeds. Endosperm extracts were prepared at various times during germination from intact castor-bean seeds and from seeds from which the embryos had been removed. The sterilized seeds were incubated either on solid water agar or on agar containing 0.3 mM-gibberellic acid. 2. Isocitrate lyase and 3-hydroxyacyl-CoA dehydrogenase had very low activities in the mature seeds, but increased 44-fold and 27-fold respectively during germination. In contrast, the extracts of mature seeds had considerable acid and alkaline lipase activity and this only increased two- to three-fold during the incubation period. 3. Incubation of the seeds with gibberellic acid accelerated the rate of appearance of isocitrate lyase and 3-hydroxyacyl-CoA dehydrogenase. It also increased the total activity attained. However, the application of hormone had, in comparison, little effect on the development of lipase activity. 4. The removal of the embryo had little influence on the development of enzyme activity in the endosperm tissue; only with isocitrate lyase was a decrease in activity observed in the absence of the embryo.


Regulation of ribonucleic acid synthesis by polyamines. Reversal by spermine of inhibition by methylglyoxal bis(guanylhydrazone) of ribonucleic acid synthesis and histone acetylation in rabbit heart. The relationship between polyamines and RNA synthesis was studied by considering the action of spermine on histone acetylation in perfused heart. In addition, the effect of methylglyoxal bis(guanylhydrazone), inhibitor of putrescine-activated S-adenosylmethionine decarboxylase activity, on RNA and polyamine specific radioactivity and on acetylation of histone fractions was also investigated in perfused heart. Different concentrations of spermine and/or methylglyoxas bis(guanylhydrazone) were injected into the heart, 15 min after beginning the perfusion. The results demonstrate that spermine stimulates the specific radioactivity of RNA of subcellular fractions. Acetylation of the arginine-rich histone fractions, involved in the regulation of RNA transcription, is enhanced by spermine. The perfusion with methylglyoxal bis(guanylhydrazone) causes a decrease in the specific radioactivity of polyamines and RNA, and in acetylation of histone fractions. However, spermine is able to reverse the methylglyoxal bis(guanylhydrazone) inhibition when injected simultaneously. From these results we may assume a possible role for spermine in the regulation of RNA transcription.


Tissue distribution of retinol and its metabolites after administration of double-labelled retinol. The tissue concentrations and distribution of radioactivity present in retinol and its metabolites were investigated in vitamin A-deficient rats 24h after injection of physiological doses (10mug) of [6, 7-14C2, 11,12-3H2] retinol. The highest concentration of radioactivity was observed in the adrenals, followed by kidney, spleen, liver, intestine and blood. The total radioactivity was greatest in urine, followed in descending order by liver, kidney, blood and intestine. The 14C/3H ratios of crude light-petroleum extracts in the liver, intestines, lungs, heart and faeces were similar to the ratio of the injected retinol dispersion. However, the 14C/3H ratios in the adrenals, kidney, spleen, blood, brain and urine were quite different from that of injected retinol. Alumina chromatography of the kidney and intestinal extracts demonstrated that retinol and retinyl palmitate are the principal forms of vitamin A present. However, alumina chromatography of the liver extract did not reveal the presence of retinol but yielded a major compound with a low 14C/3H ratio. That this compound was not retinol was shown by its inability to react with ethanolic HC1 to yield anhydroretinol. The distribution of radioactivity in ether-soluble, acidic and water-soluble fractions of urine indicated that most of the radioactivity was present in the acidic and water-soluble fractions. The 14C/3H ratios in ether-soluble and acidic fractions were higher than that of injected retinol, whereas in the water-soluble fraction the ratio was similar to the injected material.


The use of reference materials in the elemental analysis of biological samples. Reference materials (RMs) are useful to compare the accuracy and precision of laboratories and techniques. The desirable properties of biological reference materials are listed, and the problems of production, homogenization and storage described. At present there are only 10 biological RMs available compared with 213 geological and 520 metallurgical RMs. There is a need for more biological RMs including special materials for microprobe analysis and for in vivo activation analysis. A study of 650 mean values for elements in RM Kale, analysed by many laboratories, leads to the following conclusions. 61% of the values lie within +/- 10% of the best mean, and 80% lie within +/- 20% of the best mean. Atomic absorption spectrometry gives results that are 5-30% high for seven elements, while instrumental neutron activation analysis gives low and imprecise results for K. Other techniques with poor interlaboratory precision include neutron activation for Mg, polarography for Zn and arc-spectrometry for many elements. More than half the values for elements in Kale were obtained by neutron activation, confirming the importance of this technique and the need for RMs. As a rough estimate, 6 X 10(9) elemental analyses of biological materials are carried out each year, mostly by medical, agricultural and food scientists. It seems likely that a substantial percentage of these are inaccurate, a situation that might be improved by quality control using standard RMs.


Fusion power and the environment.

Fusion power and the environment. Fusion reactor design concepts are being pursued in the research and development programme of various countries and studies are being undertaken on the possible environmental impact of fusion power reactors. The paper reviews and summarizes the results of such environmental impact studies. Attention is restricted to deuterium-tritium fusion reactor concepts and a preliminary environmental impact assessment is presented. The possible inventory tritium and radioactive materials in the neutron-activated blanket structure of fusion power reactors is described and potential hazards posed by this radioactive materials inventory are discussed. Non-radiological implications and accident considerations are outlined. In conclusion, various areas still awaiting further investigation and research work are identified. The paper contains 8 tables and 50 references.


[Extracorporeal circulation. Considerations on the methods adopted]. This paper described the various types of procedures used for cardiopulmonary bypass related to the operative procedures. The Authors emphasize emodiluition and hypothermia as local as general recommend a limited use of coronary perfusion.


[Experimental observations on posttraumatic venous thrombosis]. Venous thrombosis had been experimentally induced in dogs by two different ways of trauma: contusion of whole venous wall and stripping of intimal layer. Both ways produced thrombosis in 33% of cases. The Authors describent histological findings of venous wall and thrombi with attention to genesis and evolution of these post-traumatic venous thrombosis.


[Serial determinations of serum oxytocinase and ultrasonic biparietal cephalometry in normal and high-risk pregnancies]. The value of sonor biparietal cephalometry and serum oxytocinase that we have obtained with weekly simultaneous determinations in 14 females with normal pregnancy and in 5 with pathological pregnancy, from 24th to 39th week, show a statical positive relation. Serum oxitocinase determination against hormonal tests of the phetoplancental function (urinary oestriol, pregnandiol, serum HCS, ecc.) give advantages: it is the easyer, faster and less espandove determination. Therefore we think that it is helpful to determin togheter serial values of sonar biparietal cephalometry and serum oxytocinase to anticipate the endouterine fetal growth retardation.


[Structural and functional correlations in dysectasias of junctions at various sites]. On the basis of previous studies by means of urography, renography, cholangiocholecistography, possible analogies are sought after in the behaviour of several junctions such as upper and lower uretheral, cholecisto-choledocical, eosophago-cardial. Some significant patterns were found to be in common, or close relations, among the various syndromes.


[Transthoracic electrical impedance variations in the hemodynamic evaluation of patients after open heart surgery]. Adequate assessment of cardiac function in patients who have undergone open intracardiac operations requires determination of cardiac output. Electric impedance technique of determining cardiac output in intensive care unit is presented. Routine measurement of cardiac output in the immediate postoperative period has allowed important innovations in the care of the patients: a) preclinical diagnosis of low cardiac output and prophylactic treatment, b) artificial pacing at optimal rate, c) accurate assessment of the effectiveness of the treatment measures.


[Medicolegal aspects of chronic alcoholism. Considerations on the behavior of 285 chronic alcoholics]. The Authors examined 285 male sex chronic alcoholics hopitalised in the Psychiatric Clinic of Parma University from 1969 to 1974. Clinical diagnosis, family anamnesis, degree of learning, civil status, beginning of abuse of alcoholics were considered. The Authors then, made a research at the Criminal Court records-office to verify how many of these alcoholic patients had committed crimes, what kinds, how many, related particularly to single subject's personality.


[Genetic observations on hereditary spherocytosis in some family groups in a region of Mantova north of the Po and/in the province of Parma]. Hereditary spherocytosis is an haemolitic disease, generally characterized by anaemia, jaundice, and splenomegaly. With reference to data collected in the territory of Quistello, in the Province of Mantova and in the Hospital of the City of Parma, about 280 persons were examined, belonging to the families most affected by hereditary spherocytosis. The results support the hypothesis that the disease is due to an autosomic dominant gene with an almost complete penetrance (0.9). No significant decrease in fitness, measured as a function of fertility, was observed, nor was it possible, from the data examined, to evaluate any correlation between presence of the disease and cases of abortion or perinatal mortality. It is worthy of note that all the observed cases pertain to families that are distributed along the course of the Po River. A biochemical enquiry, based upon an evaluation of the differences in protein composition between the membranes of spherocytes and normal eritrocytes, by electrophoresis on gel of polyacrylamide, gave contrasting results.


Reduction of serum lipids by means of etiroxate (Liponorm). Ten out-patients with primary Type IIa hyperlipoproteinemia and a further 10 with Types IIb, IV, and V were administered with DL-alpha-methyl-thyroxine ethyl ester (etiroxate) (20 mg twice daily) for an average of 308 days. The aim of the study was to determine the effects of the drug on the cholesterol and triglyceride levels, tolerance and side-effects, particularly in coronary patients. The T4 values rose in all but one patient and fell again when the drug was discontinued. In Type IIa patients cholesterol fell by an average of 75.5 mg/100 ml (20.6%) as compared with the period before treatment and normal triglyceride levels dropped by 17 mg/100 ml (12.6%). In Type IIb, IV and V patients cholesterol levels decreased by 69.1 mg/100 ml (21%) during treatment. Serum triglycerides, which in some patients were extremely high before treatment were only slightly affected, falling by an average of 165.3 mg/100 ml (22.8%). For the whole group of patients the fall in cholesterol during treatment was highly significant in comparison with the period before and after therapy, whereas the changes in the triglycerides were not significant. Only one patient had an increase in the frequency of angina pectoris attacks; another showed temporary restlessness and slies, were not observed. Red and white cell counts, differential blood count, thrombocytes, the transaminases SGOT, SGPT, alkaline phosphatase, bilirubin, urinalysis and erythrocyte sedimentation rate did not change during treatment. There was no lasting increase in pulse rate in any patient and no significant changes in systolic-diastolic blood pressure. ECG showed no rhythm disorders nor any other changes which were not present before treatment was initiated.


[Incidence of AgHB in non-professional donors]. The detection of Australia antigen (HBsAg) in blood donors and of the corresponding antibody, has become a routine practice in blood banks and transfusion services. They are the best possibilities currently available in the laboratory to exclude, as blood donors, the apparently healthy antigenemic individuals, whether carriers or if incubating a type B, viral hepatitis and the individuals with a past (probably subclinical) immunological experience to virus type B, as indicated by the presence of specific circulating antibodies. The fact that both hepatitis virus, A and B, may be transmitted by different routes and mechanisms, implies the risk of post-transfusion hepatitis, particularly when the infected person is asymptomatic or becomes a "healthy carrier, and donates blood. It is important to emphasize that even the most sensitive techniques currently in use are unable to detect more than 50% of hepatitis B-infected persons. They must be considered, therefore and so far, screning procedures with clear limitations. The detection of antibodies against virus type A has only very recently been accomplished, but the availability of standardized antigen is limited to a few laboratories at the present time. Research on a diagnostic test for virus A, equivalent to that of Au antigen, has proven unsuccessful up to now. The Virus Laboratory of the Hospital del Nino I.M.A.N., using the Cep method, has detected 31 HBsAg positive sera out of 6,372 voluntary blood donors attending the hospital's blood bank in the last 4 years. The resulting frequency of 4.86/1,000 is probably below the figure that might be obtained by applying more sensitive methods, periodical sampling and additional tests such as those related to liver function.


[Bases for the development of teaching, research and maternal and infant care in the rural area. The Temascalcingo plan]. The Instituto de Ensenanza e Investigaciones Rurales (Institute for Rural Training and Research) has been established in Solís, Municipality of Temascalcingo, State of Mexico. The institute is part of the Institucion Mexicana de Asistencia a la Ninez, IMAN (Mexican Institution for the Assistance of Childhood). The institute will study a system of healthy delivery in its (rural) zone of activity, based principally in programes with a strong content in the preventive and promotional aspects. For this purpose it will use in a preferential way, auxiliary and technical personnel which is being trained by the institute and that is original from the community where it will serve. At the professional level, the institute will mainly employ pediatricians, nurses and social workers that are completing their residency at the Hospital del Nino IMAN in Mexico City. These professional will obtain important supplementary training through their participation in the rural community health programes that the institute will develop.


[Subcutaneous cysticercosis. 8 cases in children]. Observations in eight patients with subcutaneous or submucous cysticercosis studied at the "Hospital del Nino, IMAN", between November 1970 and June 1975 are reported; the age of the patients varied between 4 and 14 years; six of them were females and 2 were males. One of the patients was found to have C. cellulosae in the central nervous system as well. In the presence of subcutaneous and submucous nodules, cysticercosis should be considered in the differential diagnosis, and anatomic and histopathological documentation should be sought; in cases in which cysticercosis is verified, the patient should be carefully studied, to rule out the presence of C. cellulosae in other locations, mainly the central nervous system.


[Pediatrics in Mexico. What it is and what is should be]. The present situation of the pediatrician in Mexico is described and the effects on medicine in the country are outlined. The evolution of pediatrics in the country in the past 35 years and what is expected in the future if the actual structure is not changed are discussed. What a real pediatrician should be is defined and solutions are offered to solve the problem.


[Infectious hepatitis. I. Presence of HBs antigen]. A prospective study in 268 patients of different pediatric ages affected with icteric hepatitis is presented, with a longitudinal follow-up of one year minimum. Different types of clinical evolution are described and related to the presence of HBs antigen. In 34 of the 268 patients HBs antigen was positive; in 20 of 28 patients with acute and long evolution, positivity of the antigen was transitory with an average of 46 days; in the remaining 8 of 28 patients it extended from 6 months to less than 2 years. The presence of HBs antigen is a risk that may be correlated with the tendency to extend the prolonged.


[Vascular rings].

[Vascular rings]. Anomalies in the development of aortic arches may cause the formation of a vascular ring around trachea and esophagus, responsible for compression symptoms. The most frequently found vascular rings are the double aortic arch, the right arch with left ligament and the retroesophageal right subclavian artery. The diagnosis is established by means of contrast esophagogram. Surgery is usually done through a left posterolateral thoracotomy to dissect widely the retroesophageal area, after liberating the obstruction by section of a secondary vessel. Three cases are reported to illustrate the most frequent types of vascular rings and their management.


[Surgical treatment of gastroesophageal reflux (hiatal hernia) in pediatric age]. Forty nine pediatric patients with gastroesophageal reflux were studied retrospectively; this is a 4 years experience of Hospital del Niño, IMAN. All of them were treated in the same manner, which included barium gastrointestinal series, esophagoscopy, gastric secretion test. Nissen's funduplication was performed in all of them, plus gastrostomy in those cases having esophageal stenosis. Preoperatively, eight out of every ten patients had stenosis. From the entire series, one patient died. All of them were relieved from their gastroesophageal reflux. By the ninth day following operation, one patient suffered a gastric perforation. The authors make special considerations concerning the high number of cases per year, as compared with other series. Nissen's funduplication proved very efficient to prevent gastroesophageal reflux.


[The child with learning problems].

[The child with learning problems]. Learning problems seem to have increased in the last decades in approximately 10% of the school population during the first school years. There are many causes but one of the most common are obstetric problems; also immaturity of the child because of this environment respresented in the lack of integration of his self and of his spatial concepts. Not every child who does not learn to read is dyslexic. To establish this diagnosis a complete examination that shows alterations in all areas of perception is necessary. These problems can be prevented with adequate management, starting with prenatal consultation and later on when children attend nursery school. Through games and pedagogic exercises, children will have a chance to integrate their perceptual functions and their speech, which is absolutely necessary for their learning to read and write.


[Atopic neurodermatitis, basic concepts in pediatrics]. Atopic neurodermatitis (AND) is the first or second most frequent skin diseases in childhood. It represented 15% of all skin diseases seen at the Hospital del Nino, IMAN. The clinical and epidemiologic aspects of AND, the different hypothesis of its pathogenesis, management and treatment are discussed. The importance of emotional factors in AND have been over stressed, resulting in therapeutic abuses of psychyatric drugs and psychotherapy.


[Adoerse effects by the administration of salicylates]. Two cases that illustrate one of the side-effects of salicylates are presented. Both cases manifested as non thrombocytopenic purpura. Indications and contraindications for the use of salicylates are described. Emphasis is made not to use them as analgesics or antipyretics in cases with congential or acquired defects in the coagulation mechanism. Other side-effects of salicylates are described.


[Schooling of hospitalized children].

[Schooling of hospitalized children]. The patients in IMAN's Children Hospital are treated integrally. The Service of School Education is in charge of teaching the children according to their school level. At the same time, this service tries to give children an emotional balance, stimulating them through games and working together. Such activities are carried out with professional staff belonging to different fields in pedagogy.


Carcinoembryonic antigen in an unselected elderly population: a four year follow up. Sera obtained in 1969 from 956 unselected elderly persons in Busselton, Western Australia were tested for carcinoembryonic antigen (CEA) by a "double antibody" microradioimmunoassay. Forty-four (4-5%) were positive for CEA (5 ng/ml or greater). Review of health records for the 4-year period subsequent to accession of sera showed that 6 (14%) of the 44 persons positive for CEA died of CEA associated cancers, 15 were heavy smokers, 2 had colonic diverticula and 1 a peptic ulcer. On the other hand, 18 (2%) of the 912 persons negative for CEA developed CEA associated cancers. Thus, a significantly greater proportion of cancers (P = 0-01) was found in the persons positive for CEA. Furthermore, when 21 persons who were positive for CEA in 1969, but clinically well 4 years later, were examined 2 had occult cancer of lung and colon respectively. However, the relatively low yield of diagnosis of cancer from our present population survey led to the conclusion that, if screening for cancer were to be solely dependent on testing for CEA, increased specificity and sensitivity of test systems should be awaited.


Adriamycin/cyclophosphamide and adriamycin/melphalan in advanced L1210 leukaemia. Adriamycin and cyclophosphamide are active agents in human and experimental tumours. Using the L1210 murine leukaemia, their effectiveness alone and in combination was studied. The combination is highly synergistic in this tumour, resulting in a greater than 50% survival rate when the agents used alone at optimal doses are not curative. DNA synthesis by tumour cells is substantially inhibited and the total ascitic population much reduced. In contrast, DNA synthesis in sensitive host tissues is less disturbed. There is no major difference in the pharmacology of the agents whether given alone or in combination. In very advanced disease the combination is no better than treatment with cyclophosphamide alone. The combination of adriamycin and melphalan in L1210 leukaemia also produces superior results to those obtained using either drug alone at its optimal dosage.


Cytotoxicity of cyclophosphamide in the rat incisor. Three of the 4 groups of 3 Wistar rats each were given 40 mg, 80 mg and 120 mg cyclophosphamide/kg respectively by single intraperitoneal injections. The fourth group was given 2 ml of normal saline as control. One animal from each group was killed after 1, 4 and 8 days. The incisor teeth of all experimental animals showed evidence of cytotoxic injury, which appeared to be more severe with increasing dosage, to the undifferentiated mesenchymal cells in the proliferating zone of the pulp close to the basal odontogenic epithelium, cessation of root growth and relative acellularity of the basal area of the pulp. Evidence of cytotoxicity to the odontogenic epithelium was seen only in the groups given 80 mg/kg and 120 mg/kg. Resolution of the cytotoxic injury and re-establishment of normal basal odontogenesis were seen in the 40 mg dose group by the eighth day but appeared to be slower with increasing dosage. It would seem that of the rapidly proliferating epithelial and mesenchymal odontogenic cells in the basal area of the rat incisor those in the mesenchyme may be most susceptible to the cytotoxicity of cyclophosphamide. The odontogenic epithelium may be resistant to the cytotoxicity of 40 mg cyclophosphamide/kg. The results may be of significance in the investigation of the mechanism of cytotoxicity of this cancer chemotherapeutic agent.


The ultrastructure of N-dibutylnitrosamine induced pulmonary tumours (adenocarcinomata) in European hamsters. N-dibutyl-nitrosamine induced pulmonary adenocarcinoma in European hamsters were studied electron microscopically. The tumours were composed of light and dark cells, which, due to their lamellar bodies, resembled alveolar epithelial cells Type II. As cells containing lamellar bodies also occasionally occurred with the epithelial lining of tumour associated peripheral bronchi, a possible bronchiolar origin of the neoplasms is discussed.


Cancer and ageing in mice and men.

Cancer and ageing in mice and men. In an experiment involving 950 mice with a normal lifespan of 2-3 years, in laboratory conditions, regular benzpyrene application to the skin was started at 10, 25, 40 or 55 weeks of age. The incidence rate of malignant epithelial tumours among the survivors in each group increased steeply with time. This increase was associated directly with duration of exposure but, given duration, was independent of age at the start of exposure, as were the growth rates of already established tumours. In our experiment, although age per se was irrelevant, the cancer incidence rate increased approximately as a power of the duration of exposure to benzpyrene. This shows that the observed approximate power-law increase of most human adult cancer incidence rates with age could exist merely because age equals duration of exposure to background and spontaneous carcinogenic stimuli. Thus, no intrinsic effects of ageing (such as failing immunological surveillance or age related hormonal changes) whatever need to postulated to explain the vast increases in old age of the incidence rates of such human cancers. This result can greatly simplify speculation about mechanisms of carcinogenesis.


Colorectal cancer and consumption of beef and fat. Secular, socioeconomic and urban-rural gradients and geographical differences in beef and fat consumption within the United States of America are compared with corresponding data on colorectal cancer incidence and mortality rates. These results, together with the results of most previous epidemiological studies, appear to contradict the hypothesis that beef and fat consumption are involved in the aetiology of colorectal cancer.


Humoral mediated macrophage response during tumour growth. Reticuloendothelial (RE) phagocytic and circulating plasma opsonic activity was evaluated in rats transplanted with the Walker 256 carcinoma tumour in an attempt to evaluate the role of opsonic protein in governing the functional state of the macrophage system. Animals transplanted intramuscularly with 2 X 10(4) viable tumour cells manifested 2 peaks of RE stimulation at 6 and 14 days post-transplantation with a subsequent decline in the phagocytic activity over the 14-30 day period. Increased phagocytic activity as determined by colloid clearance was primarily a reflection of hepatic Küpffer cell hyperphagocytosis while the decline in phagocytic activity was related to a decrease in Küpffer cell function. The initial peak of RE stimulation was associated with an elevation in the blood opsonin level and no significant enlargement of the liver and spleen. In contrast, the second peak of RE stimulation at 14 days was associated with both an elevation in opsonin levels and an associated hepatic and splenic enlargement. The decline in phagocytic activity over the 14-30 day interval was associated with a progressive decline in the plasma opsonic activity, a return of the spleen to its normal size in relationship to the body weight, and a persistent hepatomegaly. These findings suggest that the alterations in macrophage function during tumour growth may be mediated in part by changes in the opsonic or phagocytosis promoting capacity of plasma. Since opsonic protein contributes to the discriminatory capacity of macrophages, it is suggested that changes in the blood opsonin level may condition the anti-tumour capacity of the macrophage system with respect to host defence aginst malignant disease.


Effect of treatment with the MER tubercle bacilli fraction on the survival of mice carrying mammary tumour isografts: injections of MER at the tumour site or at a distal location. Strain BALB/c female mice bearing syngeneic implants of 2 mammary adenocarcinomata were treated with MER, x-irradiation or both. MER was administered either subcutaneously at a site contralateral to the neoplastic growth or both into such a site and directly at the tumour location. None of the treatments effected cures but many of the treated animals survived significantly longer than did the saline injected controls. There was no evidence that introduction of MER into, or directly adjacent to, a tumour is a generally more efficacious route of administration than application at only a distal site and there was, indeed, the strong contrary impression that distal treatment alone bestowed survival protection more often and to a greater extent. In no instance was there a shortening of survival time following administration of MER at a location away from the tumour implant.


Heparin, dextran 1000 and metastasis formation after I.V. tumour cell injection in dextran non-sensitive rats. The present study of the effect of heparin and dextran 1000 on the metastasis formation after i.v. tumour cell injection in dextran non-sensitive rats using a syngeneic 20-methylcholanthrene induced fibrosarcoma showed that heparin treatment decreased with formation of pulmonary metastases in animals both untreated and treated with dextran 1000. Treatment with dextran 1000 increased the formation of pulmonary metastases in animals both untreated and treated with heparin and the effect of dextran 1000 was thus not affected by heparin treatment. Heparin did not have any direct action on the tumour cells, which influenced metastasis formation. The data suggest that heparin acts as an anticoagulant with decreased microthrombus formation around lodged cells and that dextrax 1000 stimulates metastasis formation primarily by mechanisms other than intravascular coagulation.


Tissue culture studies of malignant effusions. This study reports attempts to culture tumour cells from 51 malignant effusions using standard tissue culture techniques. Cultures proliferating for more than one month were derived from 42 effusions including 24/32 from breast cancer patients and 5/6 from colon carcinomata. The morphology of these cells and their culture characteristics were compared with that of cells derived from a benign effusion. A common cell type--believed to be of mesothelial origin--was found in all cultures. In addition, fibroblastic cells were common and smaller pleomorphic cells, possibly tumour cells, were found in many effusions. The mesothelial cells were often multinucleated and grew for long periods. Although the tumour cells grew in conjunction with the mesothelial cells, all attempts at separation have failed. These studies indicate that cells derived from malignant effusions may be largely of mesothelial origin although tumour cells may also be present. The use of short-term cultures of malignant effusions as the source of cells for use as target cells in cytotoxicity tests and in chemotherapy assays is disscussed.


A test of several parametic statistical models for estimating success rate in the treatment of carcinoma cervix uteri. The parametric statistical models discussed include all those which have previously been described in the literature (Boag, 1948-lognormal; Berkson and Gage, 1952-negative exponential; Haybittle, 1959-extrapolated actuarial) and the basic data used to test the models comprised some 3000 case histories of patients treated between 1945 and 1962. The histories were followed up during the period treated between 1945 and 1962. The histories were followed up during the period 1969-71 and thus provided adequate information to validate long-term survival fractions predicted using short-term follow-up data. The results with the log-normal model showed that for series of staged carcinoma cervix patients treated during a 5-year period, satisfactory estimates of long-term survival fractions could be predicted after a minimum waiting period of 3 years for stages I and II, and 2 years for stage III. The model should be used with a value assumed for the lognormal paramater S in the range S = 0.35 to S = 0.40. Although alternative models often gave adequate predictions, the lognormal proved to be the most consistent model. This model may therefore now be used with more confidence for prospective studies on carcinoma cervix series and can provide good estimates of long-term survival fractions several years earlier than would otherwise be possible.


The modification of the renal carcinogenicity of dimethylnitrosamine by actinomycin D and a protein deficient diet. The effect of a single treatment with 30 mg dimethylnitrosamine (DMN) and 6 mug actinomycin D (ACT), given at different time intervals (ACT application to DMN, 2 h before, simultaneously, 5, 9 or 48 h later), was tested in female Sprague-Dawley rats in relation to renal carcinogenesis; additionally, the animals were fed either a normal or a protein deficient diet. The ACT treatment did not significantly modify either the kidney tumour incidence or the survival time in the different groups fed a normal diet. Nevertheless, there are indications that additional ACT application may shorten the latency period for DMN induced renal neoplasms or, when administered 5 h later than DMN, a slightly decreased and delayed tumour induction can be assumed. In groups fed a protein deficient diet, a significantly higher percentage of kidney tumour bearing animals as well as a shortened latency period were found when compared with the DMN group on normal diet, but these differences were independent of the additional ACT treatment 9 h later than DMN and were due to the protein deprivation. Morphologically, the tumours were of epithelial and mesenchymal type with a clear preponderance of the former type. Biochemical and morphological aspects are discussed.


Partial hepatectomy and toxicity of dimethyl-nitrosamine and carbon tetrachloride, in relation to the carcinogenic action of dimethylnitrosamine. The yield of tumours in the liver of rats was increased when dimethylnitrosamine was given 1, 6 or 12 h after partial hepatectomy and still further increased if it was given after an interval of 24-72 h. The increase was greater after two-thirds than after one-third hepatectomy. An increase in the number of kidney tumours was also found. Microsomal DMN-demethylase activity was depressed after partial hepatectomy for up to 6 days in mice and rats. The LD50 of DMN on the other hand was decreased for 3 days, after which it returned to normal. The extent of liver necrosis produced by DMN was increased at 6 and 24 h after partial hepatectomy but was within the usual range at longer intervals. These results suggest that prolonged exposure of the tissues to DMN after partial hepatectomy played a significant role in the development of liver tumours as well as those in the kidney, in addition to the role of regeneration of the liver, and that the relative roles were still to be elucidated.


The effect of an hypoxic cell sensitizer on tumour growth delay and cell survival. Implications for cell survival in situ and in vitro. A comparison has been made of the effects of the 2-nitroimidazole Ro-07-0582 on tumour growth delay after irradiation and tumour cell survival in vitro after irradiation in vivo. This compound has previously been shown to be a specific sensitizer of hypoxic cells. A dose of 1 mg/g body weight gave an enhancement ratio of 2-2 for both growth delay and cell survival in a system where high pressure oxygen has been shown to have no effect. However, while the hypoxic fraction in the tumour was estimated to be less then 10% from the growth delay curves, the survival curves gave a value in excess of 50%. This discrepancy probably reflects differences in the response of cells left in situ or removed and assayed in vitro.


Urinary aetiocholanolone in patients with early breast cancer from South East Scotland and South Wales. Urinary aetiocholanolone levels have been measured in 417 women aged between 20 and 70 years. The women were drawn from South East Scotland and South Wales and consisted of patients with either benign or malignant disease of the breast and control patients suffering from no detectable breast disorder. The pattern of aetiocholanolone excretion with respect to age and menopausal status has been defined in each group of patients. No significant differences in urinary levels have been detected between patients with breast disease, whether benign or malignant, and control patients. More detailed examination of the 201 women with early cancer of the breast has also shown that there is no consistent correlation between pre-operative aetiocholanolone levels and factors of prognostic significance detectable at the time of primary treatment-tumour size, grade, round cell infiltration, histological involvement of nodes by tumour and the clinical palpability of lymph nodes. It would seem, therefore, that the prognostic value of pre-operative aetiocholanolone measurements is somewhat limited in patients with early breast cancer. It is noted, however, that low levels of aetiocholanolone are associated with post-menopausal patients, a group in which the prognosis is generally poorer than that in pre-menopausal women.


Effects on serum complement of normal and pre-eclamptic pregnancy and of oral contraceptives. The complement system was studied in normal gestation and puerperium, in pre-eclampsia and in women taking oral contraceptives. In 12 normal pregnancies, CH50 titres, C4, C3, C6 and C7 were increased throughout pregnancy; the serum concentration of C1 inhibitor was decreased in the last 2 quarters but greatly raised after delivery. Oral oestrogen-progestogen contraceptives also raised C3 but in contrast to pregnancy lowered CH50,   C6 and C7. The different effects of pregnancy and of oral contraceptives may be due to materno-foetal immune reactions. In 9 patients with pre-eclamplsia, complement levels showed a wider scatter and a significantly higher C3 level than in normal pregnancy. Conversion of C3 to C3i was found in 2 of these patients.


Starch dermatitis: evidence of immunogenicity of surgical glove powder in the guinea-pig. Guinea-pigs immunized by nuchal inoculation of starch glove powder emulsified with Freund's complete adjuvant showed increased thickening of the ear erythema and monoculear inflammation after local injection of 0.1 mg starch compared with similarly treated control animals inoculated with saline and Freund's complete adjuvant. The responses in the ear of the immunized animals were most pronounceed 3-4 weeks after immunization and 24-72 h after local challenge. It is suggested that the inflammatory response in the immunized guinea-pig has 2 components: reaction to a primary irritant in the glove powder and delayed hypersensitivity to an unidentified component of the glove powder.


The effects of adrenalectomy and corticosterone on vascular permeability responses in the skin of the rat. The vascular permeability response induced in the rat by intracutaneous histamine or serotonin is noticeably influenced by previous adrenalectomy or treatment with corticosterone. Permeability responses were demonstrated by the local exudation of circulating Evans blue at sites of intracutaneous injection of the above permeability factors, the intensity of the responses being assessed by the diameter of the blue lesions as well as by the amount of exuded dye. In adrenalectomized rats maintained for 72-80 h on 0-9% solution of NaCl, the permeability response to histamine was enhanced about 10-fold, that to serotonin about 5-fold. When rats were given subcutaneous corticosterone, 1-0 mg/animal 1 h before testing, the responses to the same 2 permeability factors were decreased about 10-fold and 5-fold respectively. Corticosterone also decreased the enhanced responses in adrenalectomized rats to levels somewhat below those in mock adrenalectomized controls. The results support the proposal from other work that vascular exudation in experimental inflammation is regulated by an anti-inflammatory factor that accumulates in injured tissues and owes its effect to release of corticosteroids.


A dog model of fulminant hepatic failure produced by paracetamol administration. Oral administration of graded doses of paracetamol to dogs produced hepatic necrosis with some similarities to the clinical syndrome seen in man following a paracetamol overdose. Coma, with raised levels of arterial ammonia, was produced and the aspartate aminotransferase levels became markedly elevated in 2 animals who survived more than 24 h. However, the extent of the hepatic necrosis and the time of survival following paracetamol administration were too variable for this model to be of value for the testing of new methods of temporary liver support. When paracetamol was given by intraperitoneal injection many of the animals died of respiratory distress. Significant methaemoglobinaemia was detected, which was associated with a reduction in the arterial partial pressure of oxygen and was partly reversed by the administration of methylene blue.


The effect of coumarin on protein and PVP clearance from rat legs with various high protein oedemas. Coumarin (a benzo-pyrone) has been shown to bring about the rapid removal of protein from normal or burnt tissues and from those with lymphoedema, with or without burning. This was particularly evident when the removal of protein was compared with that of a non-metabolizable control-PVP. The mode of action would seem to be by stimulation of proteolysis. The fragments of protein could then rapidly leave the tissues because of their small size, their high diffusion coefficients and a concentration gradient which was directed from the tissues to the blood. In this way excessive amounts of protein would be removed, thus releasing the oedema fluid. The removal of non-metabolizable PVP was reduced with normal and burnt legs, possibly of stimulated phagocytosis. In the presence of lymphoedema there was a more rapid removal of PVP with coumarin; this was possibly a consequence of the great reduction of intercapillary distances resulting from the removal of oedema fluid.


A study of the action of the cationic proteins from rabbit polymorphonuclear leucocytes on the staphylococcal cell membrane. The inhibitory effect of cationic proteins from rabbit polymorphonuclear leucocytes on the oxidation of NADH by staphylococcal membrane preparations is described. Both cyanide and haematin are shown to interfere with the inhibitory process, by different mechanisms. Other authors have shown that glucose repressed staphylococci are diverted to a fermentative mode of metabolism. These findings were confirmed by demonstrating that membrane preparations from staphylococci grown in the presence of glucose have diminished cytochrome and succinic dehydrogenase levels. From a comparison of the effect of the cationic proteins on NADH oxidation in membrane preparations from organisms grown normally and under conditions of glucose repression, and from knowledge of the different susceptibility to the cationic proteins of the two types of organisms, it is suggested that the cationic proteins exert their bactericidal action on staphylococci following an energy dependent binding to the membrane.


The effect of beta aminoproprionitrile (BAPN) on experimental amyloidosis. Experimental amyloidosis was induced in mice with repeated injections of complete Freund's adjuvant (CFA) reinforced with bacterial vaccine. BAPN administered in a mixture with CFA or on its own before the injection of CFA reduced the incidence of amyloidosis. The reduction in the incidence of amyloidosis following the administration of BAPN may be due to its inhibitory effect on the oxidative deamination of amino acids, which presumably inhibit cross-linking of amyloid fibrils or interfere with metabolic pathways which involve the formations of mucopolysaccharide formation. It is suggested that the defective formation of the mucopolysaccharide-amyloid protein complex inhibits amyloid deposition and induces the activity of beta glucuronidase observed in the present study. The reduced incidence of amyloidosis following BAPN adminsitration cannot be due to lysosomal enzyme degradation of the amyloid as the activity of cathepsin D and acid phosphatase is decreased during this process.


Experimental diphtheritic neuropathy in the mouse: a study in cellular resistance. Diphtheria toxin administered by direct intraneural injection procedures demyelination in the mouse sciatic nerve. A dose in the order of 2 million times greater on an equal weight of nerve basis to required to produce the lesion compared with the dose required in the chicken.


Electron microscopic and cytochemical study of the vacuoles of regenerating renal tubular cells. The structure and acid phosphatase activity of vacuoles observed in regenerating proximal renal tubules were examined ultrastructurally. The sequestration and degradation of organelles were followed in the vacuoles, which obtain the acid phosphatase presumably from the lysosomes, and the limiting membrane of which originates from the endoplasmic reticulum. The vacuoles are regarded as autophagic vacuoles. Their appearance is correlated with the commencing differentiation of the dedifferentiated regenerating cells, which have similar regenerative phenomena.


Chromosomal abnormalities and dyserythropoiesis in the preleukaemic phase of multiple myeloma. Two patients with multiple myeloma and one patient with a plasma-cytoma are reported in whom acute leukaemia developed following long-term treatment with melphalan. Each patient had a complete remission of the plasma cell disorder during which time the bone marrow was moderately to severely hypoplastic. The end of the clinical remission was heralded by a dyserythropoietic anaemia which persisted several months before the emergence of the terminal acute leukaemia. Marked chromosomal abnormalities were observed in marrow cells during the dyserythropoietic phase.


Elevated microviscosity in membranes of erythrocytes affected by hereditary spherocytosis. Erythrocytes affected by hereditary spherocytosis (HS), obtained from several splenectomized patients, showed a varying degree of elevated osmotic fragility. In order to evaluate a possible role of the erythrocyte membrane lipids in HS, microviscosity of the membrane lipid core was measured by a fluorescence-polarization technique. Intact HS-affected red cells, as well as their ghost membranes and liposomes prepared from their lipid extract, all showed a distinctly higher micro-viscosity than the respective normal control. The increased microviscosity correlated with the severity of HS. The data support the proposition that the defect in HS-affected red cells is associated, at least in part, with alterations in the membrane lipids.


A computer program for the analysis of parallel-line bioassays of clotting factors. An interactive computer program for the analysis of clotting factor assays is described. The program provides potency estimates against a standard, and will compare the observed and expected responses of a treated patient. Tests for validity of curve fitting are provided, with a number of optional transforms. If asked, the program will provide the user with a list of valid commands at any given step, and will identify certain errors in input.


In vitro spontaneous thrombin generation in human factor-IX concentrates. A series of in vitro studies designed to ascertain the potential in vivo thrombogenicity of human factor IX-containing concentrates is described. Using concentrates obtained from several different Centres the fibrinogen clotting time with some preparations was less than 6 h and/or the recalcification time of normal plasma was shortened. In some preparations, however, the plasma recalcification time was lengthened. Further studies revealed that all diluted factor-IX concentrates generated thrombin after recalcification, and that the rate of thrombin generation appeared to be characteristic of a particular preparation. This characteristic has been designated the TGt50, which is the incubation period in minutes, after recalcification, required to obtain a 50 s clotting time of a fibrinogen substrate. The TGt50 was found to correlate most strongly with recalcification time of celite exhausted plasma (P less than 0.001), but no correlation was observed between it and the immunological antithrombin III or factor-VIII antigen levels. Evidence is presented which suggests that the thrombin generation test and recalcification time of celite exhausted plasma may represent suitable in vitro quality control assays for factor-IX concentrates.


Distribution of fibrinogen, and platelet factors 4 and XIII in subcellular fractions of human platelets. The distribution of fibrinogen, platelet factor 4 (heparin-neutralizing factor) and factor XIII amongst subcellular fractions of human platelets was determined. It was found that fibrinogen and platelet factor 4 peaked sharply in the region of the density gradient previously shown to be heavily enriched with alpha-granules. By contrast, factor XIII, fibrin-stabilizing factor, was found exclusively in the supernatant.


In vitro labelling of platelets: an experimental study on healthy asplenic subjects using two different incubation media. Duplicate platelet survival studies, using autologous platelets labelled in vitro with radioactive sodium chromate, were performed on six young healthy asplenic men. In the first experiment plasma, and in the second a Ringer-citrate-dextrose (RCD) solution (Abrahamsen, 1968), was employed as incubation medium. The uptake of chromate by the platelets was about 2.5 times higher in the RCD compared to the plasma experiments. An identical pattern for the immediate behaviour of infused labelled platelets was observed in the duplicate studies, and the recovery of platelet-bound radioactivity remained stable at the 90% level during 2 h post-infusion. In these experiments the means for platelet mean life span (MLS) were identical, 7.2 +/- 0.5 and 7.2 +/- 0.4 days, respectively. These values slightly, but not significantly, exceeded the mean platelet MLS for a control group consisting of 10 young healthy males (6.9 +/- 0.4 days). The means for platelet production rate (P) at the duplicate studies made on the asplenic subjects were 19 +/- 2 X 10(10) and 21 +/- 2 X 10(10) platelets per day, respectively, and did not differ from the mean for P obtained in the control group (22 +/- 2 X 10(10).


Ferrokinetics and erythropoiesis in man: the measurement of effective erythropoiesis, ineffective erythropoiesis and red cell lifespan using 59Fe. Existing ferrokinetic methods do not provide a direct and quantitative measurement of effective and ineffective red cell production. A new method is described for calculating the daily uptake of iron by maturing red cells and the mean red cell lifespan. Ineffective erythropoiesis and non-erythroid iron turnover are also measured. The method involves standard laboratory techniques but the analysis requires access to a computer. The preliminary results suggest that it will be a clinically useful tool for the investigation of erythroid disorders.


Hypocholesterolaemia and anaemia.

Hypocholesterolaemia and anaemia. The present study has examined the relationship and significance of hypocholesterolaemia to anaemia and to the red cell. The level of plasma cholesterol is closely related to haematocrit levels both initially and throughout the course of the anaemias associated with hypocholesterolaemia. The association is maintained, regardless of the cause of the haematocrit change, i.e. transfusion or response to treatment. Hypocholesterolaemia does not affect the red cell, i.e. its survival, cholesterol concentration or osmotic fragility and occurs in a diverse group of anaemias. As such, it is not causally related to anaemia. The changes in plasma cholesterol are most likely related to its 'redistribution' or to plasma 'dilution', with contributory factors occurring. The presence of anaemia, even to a modest degree, would be important to consider when comparing cholesterol levels between groups of individuals.


[Cytochromes b in submitochondrial particles from beef heart in the presence of redox succinate/fumarate buffer]. Aerobic red-ox titration of cytochromes b from submitochondrial particles (SMP) using red-ox succinate/fumarate couple revealed two components, one of them having E'0=80 mv; n=1 and alpha-band absorption maximum at 562 nm (b562); and the other-E'0=-25 mv; n=1 and the absorption maximum at 565 nm. Energisation of SMP, equilibrated with red-ox succinate/fumarate buffer, brought about a increase in absorption at the cytochromes b region (564-565 nm), which was reversed and prevented by an uncoupler. Energy-dependent reverse electrone transport from ascorbate+TMPD resulted in considerable higher reduction of cytochromes b with summary maximum at 563 nm with the same initial reduction level prior to energisation. The data obtained show that energy dependent  reduction of cytochromes b of SMP poised with succinate/fumarate red-ox buffer is presumably to the effect of energisation on the red-ox state of cytochrome b566. It is suggested that the transmembrane electric potential difference, generated upon the energisation of the particles, should result in re-distribution of the semi-quinone Q anion (-Q-) across membrane, thus altering the equilibrium redox-state of respiratory carriers, interacting with redox-couples -Q/Q and QH2/-Q- in the mitochondrial membrane.


[Kinetics of the in vivo synthesis of the polypeptide chain; the effect of translation inhibitors]. Effects of aurinetricarbonic acid and cycloheximide on kinetics of polypeptide chain synthesis and polyribosome protile in mouse liver cell in vivo are studied. Both compounds are found to decrease the absolute rate of protein synthesis and to increase the time of polypeptide synthesis. Cycloheximide changed the ratio of translating and non-translating ribosomes and different in size polyribosome types. Aurinetricarbonic acid exerts no effect on polyribosome profile. Effects of cycloheximide and aurinetricarbonic acid on kinetic parameters of translation and a mechanism of action of these compounds are studied.


[Age-related peculiarities of acetylation of rat liver nuclear histones]. The intensity of acetylation of different histone fraction is found to change in postnatal ontogenesis of albino rats. The intensity of acetylation of lisine-rich histone (F1) was maximal in 3-and 12-month old animals. The label incorporation into F3 (arginine-rich) histones considerably decreased in the time interval between 1st and 3d months while its incorporation increased into F2 histones furing all the period of postnatal development studied.


[Post-mortem decay of rat skeletal muscle polysomes]. Post-mortem changes of cytoplasmic RNP particles from rat skeletal muscles are studied using sucrose density gradient. The polysome destruction is found to beign within 1-2 hours after the animal death. However, a part of polysomes turned to be stable at least within 48-60 hours after the death. These polysomes incorporated 14C-leucine into acid insoluble fraction in cell-free system and were decomposited by RNase treatment (10 mkg/ml). The data suggest that within 24-48 hours of the after-death destruction the decay begins to free monoribosomes while there are still active polysomes in muscles.


[Physico-chemical properties of deoxyribonucleoprotamine from sturgeon sperm heads]. Deoxyribonucleoprotamine (DNPn) from sonicated nuclei of sturgeon sperm heads was studied by means of ring dichroism. A derivative analysis of DNA and DNPn melting curves in 1 mM Tris. HCl pH 8.0 revealed the fraction of protein-free DNA being about 30% and suggested the preferable binding of protamine molecules with AT-rich DNA regions. The latter is also confirmed by the data on ring dichroism of protein-poor soluble DNAPn fraction in 0,14 M NaCl. Ring dichroism of DNA and DNPn in 1 mM Tris coinsides at the wavelength of 310-240 nm at concentrations of 500-50 mkg/ml. Dilution of DNPn to 5 mkg-ml resulted in the decrease of the ellipticity at 275 nm and produced no effect at 260-210 nm. The effect observed is suggested to be due to a partial transition of DNA in DNPn into C-form under the dilution as a result of a higher molecule hydration and a destruction of some hydrogen bonds between guanidine residues of arginine and oxygen of phosphate groups, stabilyzing DNA in the B-form. Ring dichroism spectrum of protamine, calculated by the subtraction of DNA spectrum from DNPn spectrum at the region of 240-210 nm coinsides with that of free protamine and indicates the absence of an ordered structure in protamine molecules in DNPn.


[Physico-chemical and kinetic properties of hexokinase isoenzymes from human normal and tumor tissues]. Individual hexokinase isoenzymes (isoHK) are isolated from normal and malignant human stomach mucosa. IsoHK from tumour tissue are found to have KM for glucose 10 times as low as isoHK from normal tissue. Molecular weights of individual isoHK from normal and tumour tissues are similar (at the range of 112,000-125,000). The treatment of protein preparation with 8M urea in the presence of 1% sodium docecyl sulphate resulted in the appearance of a single band with molecular weight of 58,000-60,000 for all the isoHK under polyacrylamide gel electrophoresis. Intensive bands with molecular weight of 60,000 and 96,000 and a number of minor bands were observed under polyacrylamide gel disc elect-ophoresis in the absence of urea. 2-Mercaptoethanol did not affect the results of disc electrophoresis. It is concluded that the molecule of human hexokinase consists of two subunits with molecular weight of 60,000.


[Different forms of pyruvate kinase from the rabbit adrenal cortex]. Pyruvatekinase (PK) isoenzymes were isolated by means of (NH4)2SO4 fractionation (20-45% and 50-70% of saturation) and DEAE-cellulose chromatography. Two peaks of PK activity (I and II) were discovered under chromatography of 20-45%  saturation precipitate, and one peak (I-A)-under chromatography of 50-70% saturation precipitate. PK-II in its properties (two-peaks kinetics for phosphoenolpyruvate (PEP), the resistance to effectors) is like L-type PK, which has lost its allosteric properties in the process of long-term isolation at low temperatures. PK-I and PK-I-A have S-form kinetics for PEP. They are inhibited by L-alanine and phenylalanine, and they probably are variants of the initial K(M2) type.


[Crystallin synthesis in the lens of newborn mice]. Lenses of newborn mice were incubated for different time in the Hanks solution containing 14C-amino acids mixture. Syntheses of gamma-crystallin and subunits of alpha-crystallin were shown to start at the first minute of the incybation. The incorporation rate of 14C-amino acids into gamma-crystallin was twice as high as that into alpha-crystallin within 5 minutes of the incubation. The assembly of alpha-crystallin tetramers took place after 5 minutes from the beginning of the incubation. Preincubation with actinomycin D for 3 and 6 hours resulted in the decrease of 14C-amino acids incorporation into gamma-crystallin only. These data suggest that the synthesis of gamma-crystallin takes place on both short-lived and long-lived mRNAs. Alpha-Crystallin subunits are supposed to synthesize only on long-lived mRNAs.


[Purification and properties of acid alpha-glucosidase (gamma-amylase) from the human liver]. Acid alpha-glucosidase from human liver was 720-fold purified by means of a specific sorption on Sephadex G-150 and a specific desorption from Sephadex by the competitive inhibitor, methyl-alpha-D-glucopyranoside. The preparation obtained was homogenous in ultracentrifuge and polyacrilamide gel electrophoresis. The enzyme possessed both maltase and glucoamylase activities and splitted maltose, amylopectin and glycogen with Km values of 7mM, 7.7 mg/ml and 5 mg/ml respectively. Methyl-alpha-D-glucopyranoside competitively inhibited the enzymatic hydrolysis of polysaccharides (Ki=6.95 mM) and did not affect the maltose degradation. The sedimentation coefficient of the purified enzyme preparation was 5.4 S; in 5 M guanidine. HCl the coefficient decreased to 2.2 S, which testified to the fact that the enzyme molecule consisted of subunits.


[Isolation of cathepsins D by affinity chromatography]. The paper deals with the isolation of cathepsin D from rat liver, chicken liver and bovine spleen by affinity chromatography. The synthesis of the adsorbent was performed using the competitive inhibitor of cathepsins D and pepsin pepstatin and activated Sepharose. Application of a pepstatin-Sepharose column allows obtaining a highly active and purified enzyme in a short period of time.


[Dynamics of the biosynthesis of native chlorophyll forms from initial stages to the completion of the greening process in etiolated leaves]. The succession of the formation of the native chlorophill forms and the development of the energy migration between them was studied by means of the comparison of three spectrum types: absorption, fluorescence and fluorescence excitation, and of their second derivatives. Quantitatively the chlorophyll accumulation in 9 native forms was followed by means of mathematical disintegration of the spectra using computer.


[The fluorescence method of peroxide determination in isolated chloroplasts]. High-sensitive method of peroxide estimation in suspension of pea chloroplasts is worked out. It is based on a decrease of esculatin fluorescence due to its oxidation by peroxide with peroxidase.


[Effect of alcohols on the rate of cholinesterase decarbamoylation]. Butanol-1 and butandiol-1,4 are shown to increase the decarbamoylation rate of N-methylcarbamoyl- and N,N-dimethylcarbamoyl-cholinesterase. It is mainly due to the formation of a ternary complex NEA which is decomposed in 2,5 times faster than corbamoyl-enzyme EA. This is an evidence for the presence of some allosteric center in cholinesterase which is capable of binding alcohols.


[Effect of proteolysis inhibitors on the incorporation of labelled amino acids into proteins]. Role of peptide bond breaks in the incorporation of amino acids into proteins in a "protein--amino acid" system is investigated. For this purpose the incorporation of labelled amino acids into trypsin under the inhibition of its autolysis by a specific inhibitor from soybean and epsilon-amino-caproic acid is studied. The trypsin inhibitor from soybean is found to suppress considerably the incorporation of 14C-glycine, 14C-lysine and 14C-methionine into crystal trypsin and not to affect the incorporation of labelled amino acids into chomotrypsin, papain and carboxypeptidase. Epsilon-Aminocaproic acid inhibited 14C-glycine incorporation into crystal trypsin by 40% and did not change its incorporation level into serum albumin. The dependency of amino acid incorporation level into trypsin on the activity of autolysis in the "protein--amino acid" system is demonstrated.


[Characteristics of transglucosilase from Aspergillus batatae]. Action of transglucosilase from Asp. batatae on different substrates is studied. The ratio of transglucosilase (upsilont) and hydrolase (upsilonh) activities on maltose under the action of transglucosilases from different origins is estimated. The degree of transglucosilating (upsilont/(upsilont+upsilon/)) increases with the increase of substrate molar concentration [S]. The ratio of transglucosilase and hydrolytic activities under the interaction of transglucosilase with half-products of starch metabolism is shown to depend on the concentration of glucose, the end product. The elimination of glucose from the incubation medium produces conditions for realization of hydrolytic pathway of the half-products conversion with transglucosilase. Schemes of the combined action of transglucosilase with alpha-amylase and glucoamylase under the starch conversion in enclosed and opened (continuous glucose elimination) systems are given.


Menaquinone function in the respiratory chain of Micrococcus lysodeikticus. Menaquinone-9 which is destructed under long-wave UV-irradiation is isolated from Micrococcus lysodeikticus membranes. NAD-H, malate and lactate oxidases are observed to be inhibited under irradiation, dehydrogenases of these substrates being almost intact. Photoinactivation of menaquinone results in the reduction of only one from two cytochromes b, presented in the membrane, thus testifying the location of menaquinone-9 between cytochromes b in the respiratory chain. Reconstruction of malate, NAD-H and lactate oxidases after irradiation took place when natural menaquinone (MQ-9) or menadione (MQ-0) were added. Detailed scheme of M. lysodeikticus respiratory chain is given.


[Synthesis of thyroglobulin in the polyribosome cell-free system of the thyroid gland]. Protein synthesis (in particular, thyroglobulin) is studied in a cell-free system containing polyribosomes of thyroid gland. After the incubation with radioactive label, ribosomes were centrifugated, supernatant was dialyzed against 0.05 M Tris-HCl buffer, pH 7.2 for a night, concentrated by ficol and centrifugated in 5-20% linear sucrose gradient. 14C-radioactivity of 19S fraction (thyroglobulin) was shown to comprise about 25% of total radioactivity. The rest radioactivity was found in 3--8S fractions. The distribution of the radioactivity as it was shown by polyacrylamide gel electrophoresis is as follows: 27S--11.0%; 19S--14.2%; 12S--5.8% and 4S--7.6% of total radioactivity in polyacrylamide gel. It is supposed that two successive processes take place in thyroid gland: a synthesis of thyroglobulin subunits and an exchange of new synthesized subunits with presynthesized ones.


[The relation of membrane proteins to primary oxidation of higher ri-alkanes by Pseudomonas denitrificans]. Protein composition of enriched with cell walls membrane preparations from two Ps. denitrificans mutants is comparatively studied. Mutants have a genetic blocking of first steps of higher n-alkanes oxidation. Differences in three protein components are found using disc electrophoresis in a system containing sodium dodecylsulphate. This is supposed to be an evidence of possible relation of changed mutant proteins to enzymatic alkanes oxidation.


[Lateral diffusion of the protein components of the respiratory assembly of Microsoccus lysodeikticus]. Preparations with a selectively decreased (by 85-90%) content of NADH dehydrogenase were isolated by means of heating treatment of M. lysodeikticus isolated membranes. The degree of the reduction of the NADH dehydrogenase nearest neighbour in the respiration chain of cytochrome b556 in heated membranes is similar to that in intact membranes. It is concluded that cytochrome b556 and (or) NADH dehydrogenase are capable to lateral migration in the membrane of M. lysodeikticus, resulting in the inter-chain electrone transport. A coefficient of their lateral diffusion is calculated (D equals 8-10(-10)-2-10(-9) CM2SEC-1 At 30 degrees C) on the basis of kinetics of cytochrome reduction by NADH dehydrogenase. The electron transport, due to a diffusion of respiration carriers from one assambly to another, proceeds 100 times as slow as the electrone transport in the respiratory chain. The data obtained allow to consider the aggregation of respiration enzymes as a dynamic formation.


[Effect of polyene antibiotics on plasma membranes of dog kidney]. Effects of amphotericine B and nistatine on plasmatic membranes of dog kidney are studied. Intravenous injection of antibiotics resulted in the change of the chemical composition of plasmatic membranes: the content of proteins, lipids and RNA. The composition of membrane proteins and the quantitative ratio of separate fatty acids in lipids of plasmatic membranes also changed in the presence of amphotericine B and nistatine. It is suggested on the basis of the data obtained that the mechanism of action of polyene antibiotics in dog kidney cells is connected with the damage of membrane structures.


Study of the type of RNA, degraded by polynucleotide phosphorylase in polyribosomal fraction of rat liver. The type of RNA is studied, which is degraded by polynucleotide phosphorylase (PNPase) in the fraction of free ribosomes and ribosomes released from endoplasmic reticulum membranes with Triton X-100. Beta-32P labelled ADP, UDP, GDP and CDP are found among the degradation products of endogenous RNA of free and bound ribosomes in vitro in the presence of 32P-ortophosphate. An analysis of molar ratio of beta-32P-NDP isolated revealed that PNPase degrades RNA of GC type in both ribosome  fractions. The amount of PNPase-degraded RNA in bound ribosimes is 4-fold as high as that in free ribosomes under the same conditions. Analysis of stable 32P-RNA and rapidly labelled 32-P-dRNA, isolated from bound ribosomes after the incubation with and without inorganic phosphate, revealed that PNPase attacks the 28S fragment of RNA, which consists of about 370 nucleotides, and dRNA having a sedimentation coefficient less than 12S. The rate of dRNA degradation is considerably higher than that of rRNA. 5'-RNAase, hydrolysing synthetic homopolyribonucleotides to oligonucleotides with free 3'-OH terminal group, apparently participates, together with PNPase, in dRNA and rRNA degradation.


[Effect of growth hormone on protein phosphorylation in rat liver chromatin]. The regular injection of hormone results in a decrease of phosphate groups content in total and non-histone proteins of rat liver chromatin. The quanitity of organic phosphate in total liver histone was increased by 17 per cent. This result is due to the increase of the alkaline-labile phosphate content in lysine-rich histones (approximately by 25 per cent) and unsignificant decrease in arginine-rich histones (approximately by 5 per cent). The intensity of the 32P incorporation was increased under the effect of somatotropin in all fraction of basic proteins; this increase being especially for lisine-rich histone subfractions. The quantity of histone f1 subfractions was also increased. A possible importance of changes in the degree of chromatin protein phsophorylation for realization of growth hormone function on the transcription level is considered.


[Purification of creatine kinase from beef heart mitochondria]. 53-fold purified creatine kinase is isolated from beef heart mitochondria by phosphate buffer extraction followed by chromatography on DEAE-cellulose and KM-cellulose and preparative electrophoresis in phosphate buffer density gradient. The purified enzyme was homogenous under electrophoresis in agarose gel and moved to cathode. The enzyme did not enter into separating gel under disc electrophoresis in conditions for the separation of neutral anc acid proteins, while under conditions for separating alkaline proteins it produced five fractions. The stability of creatine kinase under storage considerably decreased after the purification.