Low-molecular-weight (4.5S) ribonucleic acid in higher-plant chloroplast ribosomes. A species of RNA that migrates on 10% (w/v) polyacrylamide gels between 5S and 4S RNA was detected in spinach chloroplasts. This RNA (referred to as 4.5 S RNA) was present in amounts equimolar to the 5S RNA and its molecular weight was estimated to be approx. 33 000. Fractionation of the chloroplast components showed that the 4.5S RNA was associated with the 50 S ribosomal subunit and that it could be removed by washing the ribosomes with a buffer containing 0.01 M-EDTA and 0.5 M-KCl. It did not appear to be a cleavage product of the labile 23 S RNA of spinach chloroplast ribosomes. When 125I-labelled 4.5 S RNA was hybridized to fragments of spinach chloroplast DNA produced by SmaI restriction endonuclease, a single fragment (mol.wt. 1.15 times 10(6)) became labelled. The same DNA fragment also hybridized to chloroplast 5 S RNA and part of the 23 S RNA. It was concluded that the coding sequence for 4.5 S RNA was part of, or immediately adjacent to, the rRNA-gene region in chloroplast DNA . A comparable RNA species was observed in chloroplasts of tobacco and pea leaves.


Interactions of gangliosides with phospholipids and glycosphingolipids in mixed monolayers. 1. The interactions among five different gangliosides and three chemically related glycosphingolipids and their behaviour in mixed monolayers with six different phospholipids were investigated at the air/145 mM-NaCl interface at pH 5.6. 2. The mixed monolayers of any of the different gangliosides showed an immiscible behaviour at high surface pressures, with absence of interactions among them revealed by an ideal behaviour for mean molecular area and surface potential per molecule. 3. This behaviour was probably the consequence of steric hindrance and electrostatic repulsions between their polar head groups. 4. Di- and tri-sialogangliosides could be differentiated from neutral sphingolipids and monosialogangliosides on the basis of their interactions with phospholipids, which were correlated to the perpendicular electric field at the interface contributed by the carbohydrate residues. 5. The presence of the phosphocholine polar head group in phosphatidylcholine was important to establish interactions with di- and tri-sialogangliosides revealed by negative deviations from the ideal behaviour for mean molecular areas and mean surface potential per molecule. 6. The possible significance of these observations is discussed in relation to the participation of gangliosides in the organization of membranes and to their capability of inducing membrane fusion.


Effects of C apoproteins on the activity of endothelium-bound lipoprotein lipase. Rat apoprotein C-II activated the hydrolysis of triacylglycerol in apoprotein-depleted chylomicrons by lipoprotein lipase in vitro and in the perfused rat heart. Apoproteins C-I and C-III-3 inhibited the hydrolysis of the triacylglycerol moiety in intact and apoprotein C-II-re-activated chylomicrons in vitro, but had no effect on the hydrolysis in situ.


Purification of the lectin from Datura stramonium. The lectin from Datura stramonium can be inhibited by oligomers of N-acetylglucosamine. This property was exploited to purify the lectin by affinity chromatography on Sepharosefetuin. The purified lectin is a glycoprotein in having subunits of 40 000 and 45 000 mol.wt.


Partial purification and some properties of a cholinesterase from bush bean (Phaseolus vulgaris L.) roots. A cholinesterase was partially purified from bush bean (Phaseolus vulgaris L.) roots by using acridinium-based ligand affinity chromatography. The procedure gave a 78-fold increase in specific activity, although at least three inactive contaminants remained. The enzyme activity was maximal against acetyl esters of choline and was inhibited by neostigmine. Di-isopropyl phosphorofluoridate completely inhibited activity at concentrations greater than 0.1 mM. The catalytic centre activity was 2 X 10(-4) times that of electric eel acetylcholinesterase. Cholinesterase activity appeared as a peak (s = 4.2 +/- 0.1 S) after isokinetic sedimentation. The Stokes radius was 4.00 nm and the apparent molecular weight was 72700 +/- 1900. The smallest active and native form of the enzyme appeared to be a monomer. This contrasts with animal acetylcholinesterases, in which the smallest active and native forms are multimeric.


Generalized microscopic reversibility, kinetic co-operativity of enzymes and evolution. Generalized microscopic reversibility implies that the apparent rate of any catalytic process in a complex mechanism is paralleled by substrate desorption in such a way that this ratio is held constant within the reaction mechanism [Whitehead (1976) Biochem. J. 159, 449--456]. The physical and evolutionary significances of this concept, for both polymeric and monomeric enzymes, are discussed. For polymeric enzymes, generalized microscopic reversibility of necessity occurs if, within the same reaction sequence, the substrate stabilizes one type of conformation of the active site only. Generalized microscopic reversibility suppresses the kinetic co-operativity of the slow transition model [Ainslie, Shill & Neet (1972) J. Biol. Chem. 247, 7088--7096]. This situation is obtained if the free-energy difference between the corresponding transition states of the two enzyme forms is held constant along the reaction co-ordinate. This situation implies that the 'extra costs' of energy (required to pass each energy barrier) that are not covered by the corresponding binding energies of the transition states vary in a similar way along the two reaction co-ordinates. The regulatory behaviour of monomeric enzymes is discussed in the light of the concept of 'catalytic perfection' proposed by Albery & Knowles [(1976) Biochemistry 15, 5631--5640]. These authors claim that an enzyme will be catalytically 'perfect' when its catalytic efficiency is maximum. If this situation occurs for a monomeric enzyme obeying either the slow transition or the mnemonical model, it can be shown that the kinetic co-operativity disappears. In other words, kinetic co-operativity of a monomeric enzyme is 'paid for' at the expense of catalytic efficiency, and the monomeric enzyme cannot be simultaneously co-operative and catalytically very efficient. This is precisely what has been found experimentally in a number of cases.


The exocellular DD-carboxypeptidase-endopeptidase from Streptomyces albus G. Purification and chemical properties. The exocellular DD-carboxypeptidase-endopeptidase of Streptomyces albus G was purified to protein homogeneity and compared with the exocellular DD-carboxypeptidases-transpeptidases of Streptomyces R61 and Actinomadura R39. The S. albus G enzyme, as it is isolated, occurs in two forms. Enzyme I (30% of the total amount) and enzyme II (70% of the total amount) are identical in all respects, except that, by polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate, enzyme I has an apparent mol. wt. (9000) that is half of that found by molecular-sieve filtration under non-denaturing conditions. Irrespective of the technique used, enzyme II has an apparent mol. wt. of about 18500.


Cell-free synthesis of metallothionein directed by rat liver polyadenylated messenger ribonucleic acid. Total RNA was isolated from rat liver polyribosomes and fractionated by oligo(dT)-cellulose chromatography to obtain polyadenylated mRNA. The mRNA was translated in a wheat-germ cell-free protein-synthesizing system containing [3H]glycine, [3H]lysine and [3H]serine. Most of the newly synthesized 3H-labelled polypeptides were removed from the cell-free products by precipitation at pH 4.0. 3H-labelled thionein chains, which were soluble at pH 4.0, were purified by activated-thiol-Sepharose 4B chromatography or by gel-filtration chromatography. Polyribosomal thionein mRNA was found to increase by at least 3-fold after parenteral administration and by 20 h thereafter the ratio of thionein mRNA to total mRNA approached that found in controls. Actinomycin D administration in vivo blocked the Zn2+-induced increase in polyribosomal thionein mRNA content. These data strongly suggest that metallothionein is an inducible protein. The mechanism of regulation appears to involve changes in the synthesis de novo of thionein mRNA and hence the pool of thionein mRNA available for translation.


Partial purification, characterization and translation in vitro of rat liver metallothionein messenger ribonucleic acid. Poly(A)+ (polyadenylated) mRNA coding for metallothioneins was purified 13-fold from rat liver polyribosomes and was identified by its ability to direct the biosynthesis of these proteins in a wheat-germ cell-free system. The carboxymethylated products of the protein-synthesizing system in vitro were analysed with sodium dodecyl sulphate/20% polyacrylamide-gel electrophoresis. The labelled compounds [3H]serine and [35S]cysteine were incorporated at high specific radioactivity into proteins that co-migrated with authentic metallothioneins. No [3H]leucine incorporation was found, in agreement with the amino acid composition of the metallothioneins. Metallothionein mRNA had a sedimentation coefficient of 9 S and carried a maximum of four ribosomes. At 5 h after a subcutaneous injection of ZnCl2 or CdCl2 (10 mumol/kg body wt.), the amount of this mRNA increased approx. 2- and 4-fold respectively, on the basis of translation in vitro. The increase in metallothionein mRNA (defined by translation in the wheat-germ system) was transient and, after CdCl2 treatment, fell back to control values by 17 h. Metallothioneins constituted a maximum of 0.8% of the total protein products synthesized in the wheat-germ system by total mRNA isolated from rat liver after CdCl2 treatment.


The separation of the mycobactins from Mycobacterium smegmatis by using high-pressure liquid chromatography. The family of mycobactins from Mycobacterium smegmatis were resolved into seven fractions by high-pressure liquid chromatography. This separation was by virtue of the differences in length and character of the long acyl substituents as shown by g.l.c. of the methyl esters of the isolated fatty acids from the fractions. As t.l.c. could also resolve the individual mycobactin fractions, it too must rely on the same differences to effect separation. As the lengths of the acyl chains were modulated by the growth conditions, a specific range of acyl groups may not be needed for mycobactin to function. This technique provides a simple means of rapidly characterizing crude mycobactins from all mycobacteria.


The covalent structure of cartilage collagen. Amino acid sequence of residues 552-661 of bovine alpha1(II) chains. The covalent structure of the first 111 residues from the N-terminus of peptide alpha1(II)-CB10 from bovine nasal-cartilage collagen is presented. This region comprises residues 552-661 of the alpha1(II) chain. The sequence was determined by automated Edman degradation of peptide alpha1(II)-CB10 and of peptides produced by cleavage with trypsin and hydroxylamine. Comparison of this region of the alpha1(II) chain with the homologous segment of the alpha1(I) chain indicated a homology level of 85%, slightly higher than that of 81% reported for the N-terminal region of the alpha1(II) chain (Butler, Miller & Finch (1976) Biochemistry15, 3000-3006). The occurrence of two residues of glycosylated hydroxylysine was established at positions 564 and 603, the first present exclusively as galactosylhydroxylysine and the latter as a mixture of galactosylhydroxylysine and glucosylgalactosylhydroxylysine. Also, two residues at positions 648 and 657 were tentatively identified as glycosylated hydroxylysines. The amino acid sequences adjacent to the hydroxylysine residues so far identified in the alpha1(II) chain were compared with the homologous regions of the alpha1(I) and alpha2 chains, but no obvious prerequisite for hydroxylation could be seen. From comparison with the homologous sequence of the alpha1(I) chain, it appears that the alpha1(II)-chain sequence presented here contains three more amino acids than that reported for the alpha1(I) chain. This triplet would be interposed between residues 63 and 64 of the reported sequence of peptide alpha1(I)-CB7 from calf skin collagen. Data on the purification of the subpeptides and their amino acid compositions have been deposited as Supplementary Publication SUP 50087 (7 pages) at the British Library Lending Division, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1978) 169, 5.


Isoelectric focusing of glutathione S-transferases from rat liver and kidney. The glutathione S-transferases that were purified to homogeneity from liver cytosol have overlapping but distinct substrate specificities and different isoelectric points. This report explores the possibility of using preparative electrofocusing to compare the composition of the transferases in liver and kidney cytosol. Hepatic cytosol from adult male Sprague-Dawley rats was resolved by isoelectric focusing on Sephadex columns into five peaks of transferase activity, each with characteristic substrate specificity. The first four peaks of transferase activity (in order of decreasing basicity) are identified as transferases AA, B, A and C respectively, on the basis of substrate specificity, but the fifth peak (pI6.6) does not correspond to a previously described transferase. Isoelectric focusing of renal cytosol resolves only three major peaks of transferase activity, each with narrow substrate specificity. In the kidney, peak 1 (pI9.0) has most of the activity toward 1-chloro-2,4-dinitrobenzene, peak 2 (pI8.5) toward p-nitrobenzyl chloride, and peak 3 (pI7.0) toward trans-4-phenylbut-3-en-2-one. Renal transferase peak 1 (pI9.0) appears to correspond to transferase B on the basis of pI, substrate specificity and antigenicity. Kidney transferase peaks 2 (pI8.5) and 3 (pI7.0) do not correspond to previously described glutathione S-transferases, although kidney transferase peak 3 is similar to the transferase peak 5 from focused hepatic cytosol. Transferases A and C were not found in kidney cytosol, and transferase AA was detected in only one out of six replicates. Thus it is important to recognize the contribution of individual transferases to total transferase activity in that each transferase may be regulated independently.


Mouse intracellular immunoglobulin M. Structure and identification of a free thiol group. Monomeric intracellular mouse immunoglobulin M (hereafter designated IgMs) was purified in milligram quantities from the plasma cells of mouse plasmacytoma MOPC 104E after lysis either in the presence or in the absence of iodoacetate. Peptide ;mapping' analysis of the IgMs after partial reduction and carboxy[(14)C]methylation to label the interchain disulphide bridges showed that the heavy-light bridge and the interheavy bridge present in the Cmu2 region were already formed at lysis. The cysteine residues in the C-terminal region of the heavy chains, which in pentameric IgM form an intersubunit bridge, had free thiol groups at lysis that were reversibly oxidized during isolation in the absence of iodoacetate, probably forming an intrasubunit inter-heavy-chain disulphide bridge. Isoelectric-focusing studies complemented the above findings, showing that all the intracellular IgMs carried free thiol groups that could be carboxymethylated at lysis, and that in non-alkylated preparations these had reversibly oxidized. On the basis of sodium dodecyl sulphate/polyacrylamide-slab-gel electrophoresis intracellular mu-chains had a consistently lower apparent molecular weight than did secreted mu-chains, and the estimated difference could be accounted for by the known difference in carbohydrate content. We present evidence that in a position homologous to that of a complex oligosaccharide in the Cmu2 region of secreted human mu-chains there is a simple oligosaccharide in intracellular mouse mu-chains that becomes complex on secretion. On the basis of the above findings, we present a model for the mouse intracellular IgM subunit and suggest a mechanism for its assembly into secreted IgM pentamers.


Evaluation of rate constants for enzyme-catalysed reactions by the jackknife technique. Application to liver alcohol dehydrogenase. Steady-state measurements of enzyme-catalysed reactions are capable of providing more information about the rate constants of the individual steps than is commonly obtained. We have applied a combination of the jackknife and non-linear regression techniques to measurements of the rate of oxidation of ethanol by NAD+, catalysed by alcohol dehydrogenase from horse liver. This has permitted values and confidence intervals to be assigned to the eight rate constants that characterize the binding of ethanol and NAD+ in random order to the enzyme, and to the net rate constant kcat. for the breakdown of the ternary complex.


Oxidation of glycine by Phaseolus leghaemoglobin with associated catabolic reactions at the haem. Leghaemoglobin from the root nodules of kidney bean (Phaseolus vulgaris) reacts in alkaline glycine solutions as a glycine oxidase in a reaction that may also be regarded as a coupled oxidation. Leghaemoglobin is reduced to the ferrous form by glycinate, the oxygen complex is formed, and finally the haem is attacked to yield a green reaction product. Glycine is simultaneously oxidized to glyoxylate, and hydrogen peroxide is generated. The initial velocity of the formation of the green product is proportional to the concentrations of leghaemoglobin and glycine, and the optimum pH for the reaction is 10.2. The green product is not formed if carbon monoxide, azide of imidazole is bound to the haem, whereas oxidation of glycine to glyoxylate is not inhibited by azide and not essentially by carbon monoxide. Haem breakdown is activated by digestion of leghaemoglobin by carboxypeptidase, and partly inhibited by catalase and superoxide dismutase.


Bile-pigment formation from different leghaemoglobins. Methine-bridge specificity of coupled oxidation. The coupled oxidation of leghaemoglobins with O(2) and ascorbate yielded oxyleghaemoglobin in the first reaction step, and the second step was the degradation of haem characterized by an A(675) increase. Leghaemoglobins were degraded to biliverdin isomers specifically, depending on the structure of the protein. The main leghaemoglobin components of Glycine (soya bean) and Phaseolus (kidney bean) were degraded to biliverdin mixtures containing about 50% of the beta-form, about 30% of the alpha-form and about 20% of the delta-isomer, whereas the leghaemoglobin I components of Vicia (broad bean) and Pisum (pea) were degraded almost exclusively to the beta-isomer, with traces of the alpha-isomer. The amino acid sequences of Glycine and Phaseolus leghaemoglobins resemble each other, as do those of Vicia and Pisum. The site specificity of bile-pigment formation from leghaemoglobins can be tentatively explained by specific differences in the amino acid sequences at those regions of the polypeptide chain that are in the vicinity of the appropriate methine bridges. The ligand-binding site in different leghaemoglobins may be outlined on the basis of the present results, supposing that the haem is degraded when a reduction product of haem-bound O(2) reacts with a methine bridge of the haem, and that the bridge specificity is regulated by hindering amino acid residues that determine the location of the bound O(2). The residue phenylalanine-CD1 appears to be further away from the haem plane or in a markedly more flexible position in leghaemoglobins than in mammalian globins. The haem-bound oxygen atom B, in Fe-O(A)-O(B), seems to be free to rotate in all directions except that of the gamma-bridge in Glycine and Phaseolus leghaemoglobins, but its position in Vicia and Pisum leghaemoglobin I might be restricted to the direction of the beta-methine bridge.


A rapid method for the preparation of relatively pure metabolically competent synaptosomes from rat brain. A rapid (less than 2h) method is described for the preparation of synaptosomes from rat brain by using a discontinuous Ficoll/sucrose gradient by a flotation technique. These synaptosomes are metabolically active and minimally (less than 5%) contaminated with 'free' mitochondria as judged by marker-enzyme assays and electron microscopy.


Effect of various methods of preparation on the apparent protein composition of eukaryotic ribosomes. An essential preliminary to stoicheiometric measurements. 1. We investigated whether there is any change in the relative amounts of ribosomal proteins during the isolation or extraction of the ribosomes by different methods, or during electrophoresis of the proteins. 2. To see whether proteins are lost (or gained) during the preparation of the ribosome we compared the two-dimensional protein pattern of three preparations: (a) ribosomes conventionally prepared by ultracentrifugation; (b) crude ribosomes obtained by pH5 precipitation; (c) crude ribosomes prepared by gel filtration. 3. To see whether proteins were lost during protein extraction we compared the two-dimensional pattern of ribosomes by using three different extraction methods (LiCl/urea, acetic acid and guanidine hydrochloride). 4. In all experiments listed above the relative amounts of the great majority of the proteins remained unchanged. We interpret this as showing that the relative amounts of ribosomal proteins (as we observed them on a two-dimensional gel) correspond to the proportions existing in the particle in vivo.


Turnover of muscle protein in the fowl (Gallus domesticus). Rates of protein synthesis in fast and slow skeletal, cardiac and smooth muscle of the adult fowl. Rates of protein synthesis in skeletal, cardiac and smooth muscle of fully grown fowl (Gallus domesticus) were determined in vivo by means of the constant infusion method using [14C]proline. In the anterior latissimus dorsi muscle, containing predominantly slow fibres, the average synthesis rate of non-collagen muscle proteins was 17.0 +/- 3.1% per day, a value higher than that obtained for cardiac muscle (13.8 +/- 1.3% per day) and for smooth muscle of the gizzard (12.0 +/- 1.9% per day). In the posterior latissimus dorsi muscle, containing predominantly fast fibres, synthesis rates were much lower (6.9 +/- 1.8% per day). In each case these average rates for the non-collagen protein were similar to the average rate for the sarcoplasmic and myofibrillar protein fractions. The RNA concentration of these four muscles showed that relative rates of protein synthesis were determined mainly by the relative RNA concentrations. The rate of protein synthesis per unit of DNA (the DNA activity) was similar in the two skeletal muscles, but somewhat lower in cardiac muscle and gizzard, possibly reflecting the larger proportion of less active cell types in these two muscles. These quantitative aspects of protein turnover in the two skeletal muscles are discussed in terms of the determination of ultimate size of the DNA unit, and in relation to muscle ultrastructure.


An analysis of errors in estimation of the rate of protein synthesis by constant infusion of a labelled amino acid. Rates of protein synthesis in tissues can be calculated from the specific radioactivity of free and protein-bound amino acids at the end of a constant infusion of a labelled amino acid (Garlick, Millward & James (1973) Biochem. J. 136, 935--945]. The simplifying assumptions used in these calculations have been criticized [Madsen, Everett, Sparrow & Fowkes (1977) FEBS Lett. 79, 313--316]. A more detailed analysis using a programmable desk-top calculator is described, which shows that the errors introduced by the simplifying assumptions are small, particularly when the specific radioactivity of the free amino acid rises rapidly to a constant value.


Turnover of muscle protein in the fowl. Changes in rates of protein synthesis and breakdown during hypertrophy of the anterior and posterior latissimus dorsi muscles. Measurements were made of the growth and of the changes in rates of protein turnover in the anterior latissimus dorsi muscle of the adult fowl in response to the attachment of a weight to one wing. Over 58 days there was a 140% increase in the protein content with similar increases in the RNA and DNA contents. The fractional rate of protein synthesis, measured by the continuous-infusion technique using [14C]proline, increased markedly during hypertrophy. This increase was mediated initially (after 1 day) by an increase in the RNA activity but at all other times reflected the higher RNA content. The rate of protein degradation, calculated from the difference between the synthesis and growth rates, appeared to increase and remain elevated for at least 4 weeks. At no time was there any suggestion of a fall in the rate of degradation. The following events are discussed as central to the changes that occur during skeletal-muscle hypertrophy. 1. Nuclear proliferation is necessary to maintain the characteristic synthesis rate because of the inability of existing nuclei to 'manage' increased protein synthesis for more than a limited period. 2. The increased protein breakdown during hypertrophy is consistent with the known over-production of a new muscle fibres and may indicate some 'wastage' during the growth. Such wastage may also be associated with myofibrillar proliferation. 3. Muscle stretch must be recognized as the major activator of growth and as such can be compared with the 'pleiotypic activators' that have been described for cells in culture.


Turnover of muscle protein in the fowl. Collagen content and turnover in cardiac and skeletal muscles of the adult fowl and the changes during stretch-induced growth. The collagen content and the rate of collagen synthesis were measured in the anterior and posterior latissimus dorsi muscles and in heart from fully grown fowl. This was done by measuring the proline/hydroxyproline ratios in the muscle and by a constant infusion of [(14)C]proline. These measurements were also made during the hypertrophy of the anterior muscle in response to the attachment of a weight to one wing of the fowl. In the non-growing muscles the collagen content was higher in the anterior muscle (22.8% of total protein) than in the posterior muscle (9.5% of total protein) and lowest in the heart (3.8% of total protein). In the two skeletal muscles a little over half of the collagen was accounted for by internal collagen (i.e. perimysium and endomysium). Collagen synthesis in these non-growing muscles occurred at 0.59%/day in each of the two skeletal muscles and at 0.88%/day in the cardiac muscle. During hypertrophy the collagen content of the anterior muscle increased, but not as fast as intracellular protein, so that after 58 days the concentration had fallen from 22.8 to 14.4% of total protein. This may have resulted from an incomplete production of the epimysial sheath, since the concentration of internal collagen did not fall and as a result accounted for over 80% of the total in the enlarged muscle. Collagen synthesis increased 8-fold during the first week of the hypertrophy, but never amounted to more than 4% of the total muscle protein synthesis. When the net accumulation of collagen is compared with the increased rate of synthesis it is concluded that between 30 and 70% of the newly synthesized collagen may have been degraded.


Regulation of prostaglandin synthesis and of the selective release of lysosomal hydrolases by mouse peritoneal macrophages. Macrophages isolated from the peritoneal cavity of untreated mice and maintained in tissue culture synthesize and release prostaglandins when challenged with zymosan. These cells also selectively release lysosomal acid hydrolases under the same conditions. The major prostaglandins released into the media are found to be prostaglandins E1, E2 and 6-oxoprostaglandin F1a, whereas prostaglandin F2a is not detected. Macrophages isolated from mice that have received an intraperitoneal injection of thioglycollate broth are far less responsive to zymosan challenge. These cells require 300 microgram of zymosan to synthesize and release one-third the amount of prostaglandins released from non-stimulated macrophages exposed to 50 microgram of zymosan. In addition, thioglycollate-stimulated macrophages release less than 10% of their lysosomal acid hydrolases when exposed to 300 microgram of zymosan whereas non-stimulated cells release approximately 50% of these enzymes after treatment with 50 microgram of zymosan. The zymosan-stimulated synthesis and release of prostaglandins are completely inhibited by indomethacin, whereas the increased selective release of lysosomal acid hydrolases is not affected. Macrophages, unlike fibroblasts, do not synthesize and release prostaglandins when exposed to serum or to bradykinin.


Biliary excretion of cyclohexylphenyl 4-[35S]sulphate in the guinea pig. The metabolic fate and mode of excretion of cyclohexylphenyl 4-[35S]sulphate were studied in the guinea pig. Up to 54.8% of the dose appeared in the bile, the majority as unchanged ester. Substantial amounts of hydroxylated cyclohexylphenyl 4-[35S]sulphate were also excreted in the bile together with minor amounts of the corresponding glucuronic acid conjugate. When isolated guinea-pig livers were perfused with cyclohexylphenyl 4-[35S]sulphate the biliary components were the same as those in the intact animal, although the relative concentration of the hydroxylated derivative was significantly greater. When the hydroxylated derivative was re-injected into guinea pigs it was excreted almost entirely unchanged in the bile. However, in the rat, it was excreted in the bile as a glucuronic acid conjugate. These findings are discussed in relation to studies carried out in the rat [Hearse, Powell, Olavesen & Dodgson (1969) Biochem. Pharmacol. 18, 181--195] and to differences in enzyme activities in rat and guinea-pig liver. The results are also discussed in terms of the molecular-weight threshold for the excretion of anions in guinea-pig bile.


The hydrolysis of phosphatidylinositol by lysosomal enzymes of rat liver and brain. 1. Lysosomes from rat liver contain two enzymic systems for hydrolysing phosphatidyl-inositol: a deacylation via lysophosphatidylinositol producing glycerophosphoinositol and non-esterified fatty acid, and a phospholipase C-like cleavage into inositol 1-phosphate and diaclygycerol. 2. The separate enzyme systems involved can be distinguished by gel filtration, differential temperature-stability and the inhibitory action of detergents. 3. The enzyme systems both have pH optima at 4.8 and their attack on a pure phosphatidylinositol substrate is inhibited by many bivalent metals including Ca2+ and Mg2+, and cationic drugs. 4. Whereas the deacylation system will attack other glycerophospholipids, the phospholipase C shows a marked specificity towards phosphatidylinositol, although it will also slowly attach phosphatidylcholine with the liberation of phosphocholine. 5. Gel filtration and temperature-stability distinguish the phospholipase C from lysosomal phosphatidic acid phosphatase, but not from sphingomyelinase. 6. Evidence is presented that an EDTA-insensitive phospholipase C degrading phosphatidylinositol is present in rat brain.


Systematic variations in the content of the purine nucleotides in the steady-state perfused rat heart. Evidence for the existence of controlled storage and release of adenine nucleotides. 1. The contents of the major purine nucleotides in the isolated non-working perfused rat heart varied systematically during 80min of perfusion. In particular the amounts of ATP, ADP, GTP, cyclic AMP and cyclic GMP in the well-oxygenated myocardium showed changes ranging from 25 to 60% of the mean concentrations. The apparent periodicity was about 30min for some and about 60min for other nucleotides. 2. These data are in contrast with measurements of parameters reflecting heart performance, which remained constant over this period of perfusion. 3. The ATP/ADP ratio, the cyclic AMP content, the GTP content and the GTP/GDP ratio in the tissue bore a constant relationship to one another, and all showed the same temporal variation. 4. Increasing the energy demand on the heart by administration of bovine somatotropin (1mug/ml) tended to damp the variations, and generally lower the content of all the nucleotides. 5. The total extractable adenine nucleotide pool also showed systematic temporal variations of as much as 1.3mumol/g wet wt. of tissue within 10min. 6. These variations could not be accounted for as inter-conversion with adenosine, other purine nucleotides, nucleosides or purine-degradation products either in the tissue or in the perfusion medium. No evidence was found in this preparation of the purine nucleotide oscillations described by Lowenstein and his co-workers [see Tornheim & Lowenstein (1975) J. Biol. Chem.250, 6304-6314]. 7. Further, the pool size increases cannot be satisfactorily explained by either synthesis de novo or the breakdown of any purine macromolecular species in the cell. Thus it is suggested that an unsuspected substantial storage form of purine nucleotide may exist in heart.


Hyperglycaemic activity and metabolic effects of 3-aminopicolinic acid. Administering 3-aminopicolinate to rats starved for 24h immediately initiated a progressive increase in blood glucose concentration. Hyperglycaemia was not the result of glycogenolysis, nor was it due to an inhibition of insulin release, since it caused marked hyperinsulinaemia. The rate of [6-(3)H]glucose disappearance from the blood of the intact rat was not altered by 3-aminopicolinate, indicating that it does not cause hyperglycaemia by inhibiting glucose utilization or by causing a redistribution of total body glucose. 3-Aminopicolinate increased the rate of fall in the specific radioactivity of blood [6-(3)H]-glucose, indicating dilution of the glucose pool by newly synthesized glucose. The rate of (14)C incorporation into blood glucose from [(14)C]alanine and [(14)C]lactate was increased 90 and 35% respectively, whereas that from [(14)C]glycerol and [(14)C]xylitol was either unaffected or slightly decreased by 3-aminopicolinate administration. Liver phosphoenolpyruvate of rats was increased to four to seven times the normal concentration 10min to 1h after injections of 50-300mg of 3-aminopicolinate/kg body wt. and the amounts of 2-phosphoglycerate and 3-phosphoglycerate were increased to three to four times normal. The high concentrations of liver phosphoenolpyruvate, 2-phosphoglycerate and 3-phosphoglycerate, as well as the enhancement of gluconeogenesis from lactate and alanine, but not from glycerol or xylitol, is compatible with an enhancement of gluconeogenesis at a step between pyruvate and the triose phosphates. After injections of 3-aminopicolinate, liver malate, citrate, aspartate, alanine, lactate and pyruvate were also increased, but to lesser extents than was phosphoenolpyruvate. The increases in some of these metabolites were approximated after an intravenous infusion of glucose, so their elevated concentration after 3-aminopicolinate administration could have been, in part, a consequence of the hyperglycaemia. The possibility is considered that 3-aminopicolinate stimulates gluconeogenesis in vivo by facilitating Fe(2+) activation of phosphoenolpyruvate carboxykinase as it does with the purified enzyme in vitro [MacDonald & Lardy (1978) J. Biol. Chem.253, 2300-2307]. In this effect 3-aminopicolinate may simulate the physiological role of the naturally occurring ferroactivator protein [Bentle & Lardy (1977) J. Biol. Chem.252, 1431-1440].


The metabolism of high-molecular-weight ribonucleic acid in hypothalamic and cortical regions of the developing female rat brain. The regional metabolism of high-molecular-weight RNA in the developing female rat brain was investigated after the intracranial injection of [32P]P1. The synthesis of polyadenylated RNA relative to high-molecular-weight RNA was determined after oligo(dT)-cellulose chromatography of total cellular high-molecular-weight RNA labelled after 4h. In both hypothalamus and cortex this synthesis was significantly higher during the first 10 days post partum than at subsequent ages. In both regions apparently more mRNA is synthesized in the young. The ratio of the specific radioactivity of cytoplasmic high-molecular-weight RNA relative to that of the nucleus, measured after a 48 h period of labelling, was considered to be an index of the nucleocytoplasmic transport of newly synthesized RNA [Berthold & Lim (1976) Biochem. J. 154, 529--539]. In the cortex, nucleo-cytoplasmic RNA transport in rats aged up to 20 days was significantly higher than in older rats, with the maximal value being attained between 16 and 19 days post partum. In contrast, in the hypothalamus, nucleo-cytoplasmic transport of RNA was low during the neonatal period and comparable with that of the mature animal. However, there were two periods of increased transport at later stages of development, the first between 15 and 19 days post partum and the second between 25 and 29 days post partum. These prepubertal changes in the nucleo-cytoplasmic transport of RNA in the female hypothalamus during weeks 3 and 4 post partum are coincident with other reported changes occurring during sexual differentiation. Differences in the timing of the maturational changes of the two brain regions thus appear to be reflected in developmental changes in RNA transport.


Interaction of progestins with steroid receptors in human uterus. Norethindrone (17beta-hydroxy-19-nor-17alpha-pregn-4-en-20-yn-3-one) and norethindrone acetate (17beta-acetoxy-19-nor-17alpha-pregn-4-en-20-yn-3-one) interfered to a varying degree, by competitive inhibition, with the binding of progesterone and oestradiol to respective cytoplasmic receptors in the human uterus. Progesterone binding to 4S macromolecule was saturable and co-specific for progestins. Competitors like norgestrel (17beta-hydroxy-18-methyl-19-nor-17alpha-pregn-4-en-20-yn-3-one), 19-norprogesterone, medroxyprogesterone acetate (17alpha-acetoxy-6alpha-methylpregn-4-ene-3,20-dione) and compound R(5020) (17,21-dimethyl-19-norpregna-4,9-diene-3,20-dione) possessed higher binding affinities for the progestin receptor. The dissociation constant (K(d)) for the progesterone-receptor interaction was 0.6-1.6nm and the receptor concentration ranged between 6600 and 8200 sites/cell. Norethindrone and norethindrone acetate competed for the progesterone receptor with inhibition constants (K(i)) of 6.8 and 72nm respectively. Gradient displacement and competitive-receptor assays indicated that norethindrone acetate-binding affinity for progestin receptor was approximately one-tenth that of norethindrone and progesterone. The progestins also inhibited oestradiol binding to 4.6S oestrogenic receptor by 8-12%, involving interaction at the oestradiol-binding site with a calculated K(i) value of 0.5-0.8mum. The competitive interaction of progestins with steroid receptors may be of putative importance in explaining the progestin action at the target site.


Effect of alloxan-diabetes on gluconeogenesis and ureogenesis in isolated rabbit liver cells. 1. Neither alloxan-diabetes nor starvation affected the rate of glucose production in hepatocytes incubated with lactate, pyruvate, propionate or fructose as substrates. In contrast, glucose synthesis with either alanine or glutamine was increased nearly 3- and 12-fold respectively, in comparison with that in fed rabbits. 2. The addition of amino-oxyacetate resulted in about a 50% decrease in glucose formation from lactate in hepatocytes isolated from fed, alloxan-diabetic and starved rats, suggesting that both mitochondrial and cytosolic forms of rabbit phosphoenolpyruvate carboxykinase function actively during gluconeogenesis. 3. Alloxan-diabetes resulted in about 2-3-fold stimulation of urea production from either amino acid studied or NH4Cl as NH3 donor, whereas starvation caused a significant increase in the rate of ureogenesis only in the presence of alanine as the source of NH3. 4. As concluded from changes in the [3-hydroxybutyrate]/[acetoacetate] ratio, in hepatocytes from diabetic animals the mitochondrial redox state was shifted toward oxidation in comparison with that observed in liver cells isolated from fed rabbits.


Growth and muscle protein turnover in the chick. The growth rates of young chicks were varied from 0 to 10% per day by manipulation of the adequacy of the amino acid and energy supply. The rates of protein synthesis in the white breast (pectoralis thoracica) muscle and the dark leg (gastrocnemius and peronaeus longus) muscles were estimated by feeding l-[U-(14)C]tyrosine in amino acid/agar-gel diets (;dietary infusion'). This treatment rapidly and consistently produced an isotopic equilibrium in the expired CO(2) and in the free tyrosine of plasma and the muscles. Wholebody protein synthesis in 2-week-old chicks was estimated from the tyrosine flux and was 6.4g/day per 100g body wt. In 1-week-old chicks the rate of protein synthesis was more rapid in the breast muscles than in the leg muscles, but decreased until the rates were similar in 2-week-old birds. Synthesis was also more rapid in fast-growing Rock Cornish broilers than in medium-slow-growing New HampshirexSingle Comb White Leghorn chicks. No or barely significant decrease in the high rates of protein synthesis, in the protein/RNA ratio and in the activity of RNA for protein synthesis occurred in non- or slow-growing chicks fed on diets deficient in lysine, total nitrogen or energy. Thus the machinery of protein synthesis in the young chick seems to be relatively insensitive to dietary manipulation. In the leg muscles, there was a small but significant correlation between the fractional rate of growth and protein synthesis. A decrease in the fractional rate of degradation, however, appeared to account for much of the accumulation of muscle protein in rapidly growing birds. In addition, the rapid accumulation of breast-muscle protein in rapidly growing chicks appeared to be achieved almost entirely by a marked decrease in the fractional rate of degradation.


An improved 11 alpha-hydroxylation of progesterone by Aspergillus ochraceus TS. 1. The stereospecific hydroxylation of progesterone exclusively to its 11 alpha-hydroxy derivative by Aspergillus ochraceus TS is reported. 2. There is no secondary metabolite (6beta, 11 alpha-dihydroxyprogesterone) formed even when the transformation was attempted with different concentrations of the substrate (200 microgram/ml-200 mg/ml) for prolonged with Zn2+ at a concentration of 50 microgram/ml identical results were obtained. 3. Similar results were also obtained at different pH values of the culture medium.


Malonaldehyde formation in intact platelets is catalysed by thromboxane synthase. Imidazole and compound L8027 (selective inhibitors of thromboxane synthase) produced parallel inhibition of malonaldehyde and thromboxane B2 secretion induced by collagen or thrombin in gel-filtered suspensions of human platelets. Comparing the effects of these inhibitors and aspirin on secretion of granule constituents indicated that platelet degranulation depends mainly on thromboxane production; prostaglandin endoperoxides contributed little.


The effects of food deprivation on protein turnover and nucleic acid concentrations of active and immobilized extensor digitorum longus muscles of the rat. Deprivation of food caused significant changes in the weight, protein content, protein turnover and RNA concentrations of the extensor digitorum longus muscle. Simultaneous immobilization to render the muscle inactive did not make the tissue any more susceptible to the effects of starvation. In contrast, immobilization in a stretched state resulted in less muscle wasting after deprivation of food.


Initiation of transcription in normal and phosphorylated rat liver nucleosomes. Initiation sites were enumerated in rat liver nucleosomes with Echerichia coli RNA polymerase. One site was present in approx. 3.5 mononucleosomes and in a 1200-base-pair length of polynucleosomes. S-phase nuclei or normal nuclei phosphorylated in vitro showed increased numbers of sites; the elongation rates were unchanged.


Activation of pyruvate dehydrogenase in the perfused rat liver by vasopressin. The proportion of pyruvate dehydrogenase in its active form is doubled in rat liver within 5 min of addition of vasopressin to the perfusing medium.


[Epilepsy and the driver's license].

[Epilepsy and the driver's license]. 143 older than 18 years epileptic patients have been considered under the concers of their driving licence. The 33,5% of them was already in hold it. Epilepsy was under different clinical forms. The majority of the subjects would suffer from generalized primary suizures, otherwise from partial fits, either elementar or complex. Subjects who already had the licence (37 over 75 men and 15 over 68 women) were presenting most scanty crisis, or since one year had non suffered from any at all. The frequency of crisis was very low for all the patients who had presented epilepsy before beingin permitted to drive; no question had been raised for them. Subjects without licence (25 men over 42 and 18 women over 53) had not been permitted to drive because of their illness. This group was mainly composed by patients either suffering from epilectic cerebropaty from very frequent fits, or from both. It is maintained as reasonable that italian laws conform to those within other E.E.C. countries for what concerns driving licence for epileptics; these patients, whether controlled, are assumed as well capable as accountable in mastering their condition, even when driving.


[Diagnostic and surgical problems of the laryngocele (author's transl)]. The Authors take into consideration some of the laryngocele cases which came to their observation and do some considerations about diagnosis and surgery of this non-frequent disease of the larynx. They explain the various surgical techniques for the exeresis of the three types of the laryngocele: external, internal and mixed. They describe a new technique for the removal of the internal laryngocele through direct mycrolaryngoscope endoscopy by electric dissection. Such method, when correctly practicable, offers some important advantages in respect of external surgery techniques.


[Intradural rupture of an intervertebral disk]. Since the first description of ruptured lumbar disc, erosion of a fragment of disc through the dura mater has been mentioned only rarely. The authros report two cases occurred among 1,078 herniated discs surgically treated in their department over a period of 8 years, from January 1st., 1970 through March 31st., 1978. Various factors that might contribute to this relatively rare complication of disc disease are mentioned, and literature on the subject is summarized.


[Repeated attempted suicides: a clinical study (author's transl)]. In this work we have again examined a sample of 500 attempted suicides which took place in Parma between September 1971 and January 1976. We have made a distinction between the various types--those who tried only once and those who repeated their attempts, and have also taken into consideration other factors--sex, marital status, family background, level of education, financial position, as well as the method of the attempted suicide and the mental condition of the patient when under observation. The main points to emerge were: a) there was a much higher rate of mental illness among the patients who had repeated their attempts, (66,6%), in comparison to those who had tried only once (19,5%). b) while there was already a high proprotion of females who made one attempt (74%), the rate rose even higher so with those who repeated their attempts (88,8%).


[Preventive and interceptive orthodontics]. The Authors are stating the importance of prevention in Dentistry so as to stop anomalies of jaws and teeth of from forming. They mean therapy all those measures to use with simple means, both surgical and Orthopedic, and them detting its limits and possibilities. A classification is being proposed which will divide them into prophylaxis, prevention, interseption, and early therapy.


[Behavior of the bi-parietal diameter (BPD) and antero-posterior diameter of the abdomen (APDA) in insufficient intrauterine development of the fetus: preliminary notes]. Considering the PIFG ultrasonic diagnosis limitations bu the only Biparietal Diameter (BPD) estimation, the autors test the possibilities of a new technique: the serial measurement of Antero-Posterior Diameter of Abdomen (APAD) and especially the head/abdomen diameters ratio. The preliminary data are enough confortable allowing us to improve considerably the success in PIFG diagnosis (44,44% to 80%).


[Thienylic acid, a new drug with saluretic and uricosuric activity. Preliminary data]. The effects of ticrynafen (250-500 mg) on salt-water and uric acid metabolism have been studied in 18 patients with no haemodinamic abnormalities or salt-water repletion (cardiac failure, oedema). The main results are: -- an effective natriuresis is observed in the first days and is attenuated thereafter. In subjects with a reduced GFR, a negative salt balance is obtained altough the volume of diuresis is not significantly increased. -- The potassium loss is variable according to dosage (maximum at 500 mg), renal function (low when reduced). -- The increase of urinary uric acid excretion and the lowering of blood uric acid concentration are rapid and prolonged. In conclusion, we confirm the effective natriuretic and uricosuric properties of ticrynafen.


[Current trend in the medical treatment of oxalic calculosis]. On the basis of to-day knowledge about metabolism and excretion of oxalic acid, the rationale of therapy of stone pathology is revieved. The problems of both primary and secondary oxaluria and of inhibiting factors of cristalisation are particolarly discussed.


[Acute bacterial nephritis in diabetics (author's transl)]. The AA. describe an unusual form of severe grahm negative bacterial infection of the renal parenchima that occurs infrequently in adult patients, most of whom are diabetics. During the acute phase, the kidney becomes smoothly enlarged, with marked impairment of contrast material excretion. The urographic and echographic findings simulated a renal neoplasm; on the contrary the selective renal angiography excluded the presence of a neoplastic blood circulation. This bacterial infection produces an inflammatory infiltrate surrounding and occluding the interlobular arteries in the cortex, with secondary ischemy. A precious and appropriate antibiotic therapy causes a rapid return of renal function; on the contrary this process may produce a globally small kidney in the long run.


Elucidation of the receptor-bound conformation of the enkephalins. The biologically relevant conformers of enkephalin predicted by solid state, solution state, and theoretical energy studies have been compared with the published structure-activity data on these compounds. No conformational technique proposes a model consistent with all the pharmacological data; the shortcomings of each approach are evaluated. An alternative approach, which correlates the structure-activity data of opiate compounds with that of the enkephalins, is described and shown to produce a model consistent with the available structure-activity data.


[Determination of the plasma level and excretion to tempidon in man after oral use]. Tempidone is original Bulgarian preparation, synthetized in NIHFI (Zelayskov Bikova). The plasma level of the preparation is determined after single oral administration in doses of 60 and 120 mg and for a period of five days in a dose of 20 mg three times daily per a person. It is shown that tempidone is quickly resorbed and is excreted unchanged mainly in urine.  The preparation does not cumulate. The content of tempidone in plasma is determined by the method of thin-layer chromatography, but in urine-spectrophotometricaly.


Index of permeability of large arteries to labeled albumin after administration of prostaglandin E2. Prostaglandin (PG)E2 tends to increase the permeability to labeled albumin of the arterial walls of rabbits. The blood pressure decreases after administration of PGE2. The increase in permeability is probably due to direct effects of prostaglandin upon the endothelium, perhaps to an increase of cytopempsis or formation of leaks in the integrity of the cell layer.


[Effect of isometric exercise on the lesser circulation in a group of patients with mitral stenosis]. The hemodynamic changes of the pulmonary vascular system in patients with mitral stenosis, has been evaluated during isometric exercise (handgrip). Heart rate, pulmonary artery sistolic, dyastolic, mean and "wedged" pressure, end-dyastolic pulmonary vascular and trans-mitralic gradient, total pulmonary resistences increase significantly. Cardiac output and pulmonary vascular bed are probably related to the tachycardia induced by the handgrip, and to the conseguent shortening of the dyastolic left ventricular filling time.


[Preliminary note on a model of cup-shaped deformed human erythrocyte]. We have developed a very elementary model for the cup shaped erythrocyte, in order to obtain some geometrical informations about the cellular contour and mould of the membrane, with regard to the territories of the cell, less accessible to the microscopical observation.


[Analytical contribution to the morphological study of the normal human erythrocyte]. This note introduces a new, simple analytical function as a geometrical model for the human erythrocyte (GR). This profile function contains three shape coefficients (a1, a2, R) and shows a considerable quickness of computation.


Improved assay of urinary total 17-hydroxycorticosteroids. A reliable method for the quantitative determination of "total 17-hydroxycorticosteroids has been described. Urine is subjected to reduction with sodium borohydride which reduces the 17-hydroxy-20-keto-21-deoxy steroids to 17,20-dihydroxy-21-deoxy steroids and 17-ketosteroids to C19 17-hydroxysteroids. Subsequent oxidation with sodium bismuthate oxidizes all the C21 17-hydroxysteroids to the corresponding 17-ketosteroids, which are extracted with CHCl3 : Bu-OH using ammonium sulfate as the salting out agent and finally the color reaction is performed with m-dinitrobenzene and the absorbance is measured. The 17-ketosteroids originally present in the urine do not interfere, since NaBH4 reduces them to C19 17-hydroxysteroids which cannot be oxidized with sodium bismuthate and do not respond to the color reaction with m-dinitrobenzene.


The erythropoietic role of the heart in catfish (ictalurus melas). In Catfish, the kidney is the hemopoietic organ. On heart imprints of Catfishes, there were observed cells of the hemopoietic series. In this work it was studied how much the heart can intervene in the erythropoietic process. In normal animals the heart intervenes as a erythropoietic organ in the spring when the hemopoietic activity is more intense. In partially nephrectomized animals the heart has an erythropoietic activity also when, after nephrectomy, the hematic equilibrium has returned to normal. Cells at the same stage of development were observed on the heart and on the kidney of partially nephrectomized animals. In animals treated with acetylphenylhydrazine (hemolitic agent), the heart intervenes in the erythropoiesis also when hematic equilibrium is lightly altered. The lymphoid hemoblasts are also shown to be precursores of red cells.


Specific characters of serum MAO in dogs. The effect of Tris-hydroxymethylaminomethane (Tris) on MAO activity in dog serum was studied by a modification of the method of McEwen and Cohen. Partially purified MAO from dog serum was inhibited 75% and 31% by 10 mM and 1 nM Tris, respecitively. The inhibitory effect of Tris was 1/10 of that by nialamide and 1/1000 of that by catron. Tris also slightly inhibited MAO activity in rabbit serum, but did not affect MAO from bovine or human serum, or from dog liver, kidney or brain. The extent of inhibition of dog serum MAO by Tris remained constant during incubation for 3 hrs. The inhibition was found to be reversible and noncompetitive. Benzylamine was most rapidly oxidized by MAO of dog serum followed in order by amylamine, beta- phenylethylamine and tyramine, while tryptamine and serotonin were not oxidized. Tris inhibited MAO activity with benzylamine or butylamine as substrates, but it was scarcely inhibitory with tyramine or beta-phenylethylamine as substrate. This work shows that Tris is a specific inhibitor of dog serum MAO and suggests that dog serum MAO may differ in enzymic properties from MAO in other animals.


Heart proteins. Prevention of the denaturation of actomyosin by sodium glutamate. The storage of actomyosin isolated from bovine heart for one week either at +4 degrees or frozen at -5 degrees results in deep structural changes in the molecule of actomyosin, while storage of the actomyosin at the mentioned temperatures in the presence of sodium glutamate preserved the characteristic structure of actomyosin molecule as revealed by electron microscopy.


Relation between haemolymph proteins and fat body during metamorphosis in Sarcophaga lineatocollis. Histological changes in the fat body and in the qualitative haemolymph protein picture has been observed during metamorphosis in Sarcophagalineatocollis. A clear correlation exists in the synthesizing machinary i.e., adipose tissue and the haemolymph proteins. Proteins get accumulated in the fat body at the time of pupation to be made available for further metabolic processes occuring during the metamorphosis. A protein fraction identical to human serum albumin like protein could not be observed in this insect species.


Effect of vitamin A deficiency on hepatic microsomal and colon mucosal mixed function oxidase. IV--Influence on aflatoxin B1 metabolism, ethylmorphine and epoxide hydrase activity. Male, weanling rats, divided into two groups were maintained for 45 days on a corn-based diet containing 5 mg vitamin A palmitate per kg diet (Group 1, normal animals) and without the vitamin (Group 2, dificient animals). Fifteen hours after the last feeding, the animals were decapitated and liver microsomes and colon mucosal epithelial homogenates were prepared and used to investigate the relative activities of the mixed function oxidase (MFO) and epoxide hydrase (EH) enzyme systems. The sequential metabolism of aflatoxin B1 (AFB1) and its epoxide AFBepox) product, respectively, were also estimated by measuring apparent maximal velocities (Vmax) and Michaelis constants (Km) for ethylmorphine (EM) N-demethylase and styrene oxide hydratase. The Vmax data indicated that MFO activity in the liver and colon was not rate-limiting in the two groups of animals but the reverse were observed with calculated reaction rates at concentrations above (0,03 mM) for EM N-demethylase only. In both organs, styrene oxide hydratase depict calculated reaction rates which are not rate-limiting for all the concentration range (0,001 to 3,00 mM). If these reaction rates are applied to AFB1 metabolism, it may be concluded that MFO and not epoxide hydrase (EH) activity is a critical agent under vitamin A deficiency in AFB1 toxicity and/or carcinogenesis. Measurements of AFT1 metabolism both in terms of substrate disappearance and product formation do not confirm this observation except for the production of AFR0 and compounds of unknown structure at the origin which may embody the critical factor(s) that promotes colon carcinogenesis under vitamin A deficiency.


Inactivation of prostaglandin E2 in the stomach of pregnant and oestrogen pretreated rats. The stomach of pregnant and oestrogen pretreated female rats were found to inactivate significantly exogenous PGE2 when administered orally. The mean basal acid output of pregnant and oestrogen pretreated female rats were also diminished by oral infusion of PGE2. Though the exact mechanism for these phenomena cannot be readily seen from this work, it is suggested that metabolites of PGE2 may be responsible for the acid lowering and ulcer ameliorating effects of PGE2.


Differential arginine dependence and the selective cytotoxic effects of activated macrophages for malignant cells in vitro. Normal and neoplastic cells from 4 species (man, rat, mouse and hamster) were examined for their dependence on exogenous L-arginine in tissue culture. The malignant cells required a higher concentration of L-arginine in the medium than their normal counterparts (with similar doubling times) to maintain optimal proliferation. Complete arginine deprivation resulted in equal growth inhibition of normal and malignant cells, but more rapid cytolysis of the malignant cell. Deprivation of L-arginine, followed 24 h later by rescue with L-arginine, allowed normal cells to proliferate, but the reproductive capacity of the malignant cells was irreversibly impaired. Since the cytotoxic activity of LPS-activated macrophages was associated with the release of arginase and was abrogated by excess L-arginine, it is suggested that the biological basis for the selective effects of such macrophages may reside in the L-arginine dependence of the target cells.


Leucocyte-migration-inhibition test in patients with colorectal cancer: clinicopathological correlations. Leucocyte-migration-inhibition test was used to study the immune reactions of leucocytes from 136 colorectal cancer patients, 43 patients with non-cancerous chronic colorectal diseases and 82 controls, with saline extracts of HT29 line. A positive inhibition was found in only 43% of colorectal cancer patients. It was higher in carcinomas of limited extension than in invasive ones (64% against 39%). Furthermore, operation by itself had a depressive effect on the reaction, as the positivity in 25 patients tested twice was 64% before operation and 32% after. Leucocytes from patients with non-cancerous chronic colorectal diseases gave many positive reactions (65%). The percentage of positivity was about the same for diseases with high, low or no risk of cancerization. Hence the antigen(s) of tumour extracts that react with patient's leucocytes are, at least partially, unrelated to cancer.


Monitoring salivary misonidazole in man: a possible alternative to plasma monitoring. Concentrations of misonidazole and its O-demethylated metabolite Ro 05-9963 in the plasma and saliva of 10 patients with malignant disease have been determined. A good linear correlation was established between plasma and saliva misonidazole concentration, and salivary sampling was found to be suitable for the estimation of a number of pharmacokinetic parameters. Data are also presented for serial tumour cencentrations of misonidazole and Ro 05-9963 in 3 of the 10 patients. Monitoring of salivary misonidazole concentration appears to be a useful alternative to plasma monitoring, particularly for those patients in whom plasma sampling is unsuitable or impossible.


Clinical response and plasma levels of 5-fluorouracil in patients with colonic cancer treated by drug infusion. Concentrations of 5-fluorouracil (FU) were measured in the plasma of patients receiving i.v. infusions of the drug for 5 days as treatment for adenocarcinoma of the gastrointestinal tract. Concentrations of FU varied widely in many patients. Concentration of drug X time of infusion (C X t values) were calculated. Patients showing a partial response or stabilization of disease had significantly higher C X t values than non-responders. Methyl CCNU did not affect the C X t values of FU. Determination of the plasma concentration of FU would allow the dose of the drug to be adjusted to maintain high concentrations of FU in the plasma. Our data suggest that such high concentrations would increase the response rate in this disease.


Influence of anaesthetics on tumour-cell kill and repopulation in B16 melanoma treated with melphalan. The influence of anaesthetics on the in vivo response of B16 melanoma to melphalan was studied using an in vitro cell-survival assay. Three anaesthetics were used, Saffan (Althesin) Sagatal (Nembutal) and Hypnorm. When Saffan was administered to tumour-bearing animals before melphalan there was a significant increase in tumour-cell kill. This effect was not observed with Sagatal or Hypnorm. Maximum increase in tumour-cell kill was achieved when Saffan was administered about 1 h before melphalan, and was dependent on Saffan dose. Clonogenic tumour-cell repopulation after melphalan was rapid (TD - 1 day) and the rate was similar from 2 levels of cell kill. When Saffan was combined with melphalan the repopulation rate was the same as with melphalan alone, and the increased cell kill was reflected in increased growth delay. The in vitro response of B16 melanoma cells to melphalan was unaltered by pretreatment with, or simultaneous exposure to Saffan. The results suggest that the mechanism of the enhanced cell kill in vivo is probably due to an indirect systemic effect, rather than a direct effect on the tumour cells.


Relationship between oestrogen-receptor content and histological grade in human primary breast tumours. A series of 300 patients presenting consecutively with primary operable breast cancer has been studied. A significant correlation was found between oestrogen-receptor (ER) content and histological grade: the better-differentiated tumours rarely lacked receptor. This correlation was significant only in women defined as post-menopausal. Data on early recurrence of disease indicate a worse prognosis for women in whom primary tumours are ER-.


The blood supply of colorectal liver metastases. Post-mortem studies suggest that liver metastases obtain the majority of their nutrition from the hepatic artery; however, cytotoxic arterial perfusion with or without hepatic-artery ligation has not proved entirely successful as a therapeutic regime. In this study we have measured blood flow into colorectal liver metastases using xenon-133 (133Xe) clearance in patients undergoing surgery for colorectal cancer. Pre-operative measurements after direct parenchymal injection gave a mean flow of 41.5 +/- 22.5 ml/min/100 g which after hepatic arterial occlusion perfusion, was reduced to a mean of 5% of the pre-occlusion value. Dynamic blood-flow studies using the gamma camera were performed in the post-operative period by administration of 133Xe into both hepatic arterial and portal venous catheters. The initial distribution images indicated a predominant arterial perfusion to the metastases, but after hepatic-artery ligation, portal-vein perfusion to the metastases was statistically significantly increased. Hence, a compensatory haemodynamic mechanism exists which may account for the poor results of hepatic-artery ligation and perfusion alone.


Investigation of populations of herbaceous plants in natural conditions and under cultivation. The results of experimental investigations of the morphogenesis of vegetative organs of plants under conditions of cultivation indicated that conclusions about the true composition of populations cannot be drawn from data obtained from descriptions of plants in nature (we have in mind the following characteristics: structure, type and dimensions of shoots, form of leaves, form and dimensions of the root system, etc.). These descriptions make it possible to ascertain only the fact of variability of plants and to characterize specific variance from the norm of reaction to given conditions, which vary for each individual. The true composition of a natural population may be determined by growing plants in an area where there is no competition among them and where all factors are standardized. Only under such conditions is it possible to study the morphogenesis of vegetative organs.


Theory of transcapillary (transmembrane) exchange. Some aspects of the hypothesis formulated earlier by the authors concerning the dual character of transcapillary (transmembrane) exchange are discussed. A physiological and mathematical basis is presented for the fact that transmembrane flow of liquid into interstitial space (that part of it which does not depend on the functioning of the endothelium) is carried out both by steady-state flow, according to Starling's hypothesis, and by pulsatile flow as a result of the pressure of pulse in a capillary as recorded by Widerhielm, et al. in 1964. The authors believe that the pulsatile (fluctuating) character of transmembrane flow is efficient because of the possibility of a more versatile process of regulation within homeostatic control, which in turn is also extremely efficient from the standpoint of attaining the most effective system with the lowest energy expenditures, which are self-adjusting during the performance of specific physiological tasks and when responding to various disturbing influences.


Modern electronystagmography for vestibulometry practice. The following problems of the practical use of electronystagmography (ENG) are examined in the article: direct and indirect ENG recording, types of amplifiers, determination of the time constant of the amplifier of the recording instrument, specific significance of the values of the time constant and amplification for the information content of the nystagmus indices, limits of the linear relation between eye movements and their recording on an instrument with a different amplification and time constant, calibration of eye movements and calibration of the instrument, effect of light on the value of the corneo-retinal potential, value of the angle of calibration of eye movements with fixation of the gaze in the middle position or only at the extreme points of the central angle, paper speed when recording nystagmus, and type of recorder pen. On the basis of an analysis of 4325 EOG and ENG new principles were established and appropriate recommendations were made for improving the quality and effectiveness of electronystagmography. With consideration of the established new facts the recommended technique of modern electronystagmography is presented.


Influence of products of the vital activity of helminths on the corticosterone content in the adrenals and blood. The content of corticosterone in the adrenals and blood plasma, as well as the weight of the adrenals and their histology, were investigated in 77 inbred rats (38 animals of the August line and 39 animals of the Wistar line). It was shown that after products of ascarid metabolism were administered to the experimental rats, the corticosterone content in the adrenals and blood plasma changed substantially. Despite the equal doses of the agent administered, statistically significant differences between lines were detected in the corticosterone indices in the blood plasma of the experimental rats, and they were also present in the control (healthy) animals. In the latter, no differences between lines were established in the corticosterone content in the adrenals, although in the experimental rats these differences arose at many periods of observation. It is concluded that the level of corticosterone content of the blood in the initial normal state, as well as the degree of its deviations from the initial norm, are determined (with equal conditions with respect to paratypic factors) by the genetic constitution (genotype) of the organism.


Nerve trunk excitability and excitability of individual nodes of Ranvier in frog nerve fibers. It has been found that the duration of the absolute and relative refractory phases at individual nodes of Ranvier in myelinated nerve fibers is longer (by 39 and 33%, respectively) than in the nerve as a whole. In addition, at individual nodes of Ranvier in isolated nerve fibers the phases of facilitation and prolonged subnormality are absent. If, however, one prepares single nerve fibers taking precautions against stretching the node of Ranvier (preparations with "closed" and "sheltered" nodes), one may observe in them both facilitation and prolongation of the subnormal phase. It has been concluded that the procedure for preparing single nerve fibers leads to substantial changes in the functional properties of the excitable membrane at the node of Ranvier and disturbs the integrity of the surrounding ionic barrier.


Advantages of using the species Solanum chacoense in breeding virus X-resistant potato forms. The results of checking the resistance of diploid and polyploid specimens of the species Solanum chacoense to virus X are presented. The advantage of using this species in breeding resistant forms is shown.


Changes in the nuclei and chloroplasts in cells of big bud-infected tomatoes. Electron-microscopic studies of ultrathin sections of young tomato shoots infected by big bud showed that the mycoplasma causes pathological changes in the cell nucleus and chloroplasts.


[RNA transport from rat liver cell nuclei in vitro. Release of rapidly labeled RNA from isolated nuclei in a cell-free system in the presence of RNAse affectors]. A cell-free system was developed and characterized, which supported RNA release from isolated rat liver cell nuclei. The RNA release in the system seemed to be dependent on the presence of ATP as an evergy source and of dialized cytosol as far as on the temperature level in the incubation mixture. In vitro effects of a number of RNase affectors from cytoplasm and of related exogenous compounds on the RNA release were studied. It was shown that RNase inhibitors such as heparin, PVS and rat liver cytoplasmic RNA were capable to stimulate the RNA release, while the natural inhibitor from liver cytosol failed to influence the RNA relase. Spermidine and PCMB lowered the rate of RNA release from nuclei. The results are discussed in connection with possible role of nuclear RNases and cytoplasmic factors in nucleocytoplasmic transport of RNA.


Effect of detergents on radiothermoluminescence of Chlorella. Radiothermoluminescence (RTL) of Chlorella cells cultivated in a medium in the presence of a detergent was studied as a function of their contact time with the detergent in the temperature range from -196 degrees to +150 degrees C. The concentration of the toxicants blocking cell division caused noticeable changes in the shape of the liminescence curve beginning 1.5 h after adding the detergent to the medium. Additional luminescence peaks were noted in the -95 degrees and +120 degrees temperature region. A correlation was found between the change of luminescence intensity at -95 degrees bleaching of the cells, and their viability as a function of their contact time with the detergent.


Influence of phosphorus on the composition of polar lipids of Actinomyces olivaceus. The influence of phosphorus on the composition of the lipids of Act. olivaceus was studied. It was found that the phosphorus content in the culture medium can serve as a regulator of the synthesis of definite lipids. In the presence of a phosphorus deficiency in the medium (0.0006 g/100 ml), not only the ratio of the polar and neutral fractions, but also the composition of the polar lipids changes, namely: The content of cardiolipin and phosphatidylinositol mannoside is decreased; the content of phosphatidylethanolamine drops from 25.6% to 1.25%. An ornithine-containing lipid is detected among the polar lipids (4--4.5%). Changes in the composition of the membrane lipids are not accompanied by any visible sharp changes in the structural organization of the membrane apparatus.


[Transport of RNA from rat liver cell nuclei in vitro. Effect of superoxide dismutase on the release of rapidly labeled RNA from isolated nuclei]. Purified superoxide dismutase from beaf and rat liver cytosol was found to inhibit in vitro a release of the newly synthesized poly(A)-containing RNA from isolated hepatocyte nuclei in a cell-free system. The inhibition was concentration-dependent. Similar effect was observed with Cu2+ and coppertyrosine complex, which possess SOD-like type catalytic activity. The effectiveness of the complex and of Cu2+ however was an order smaller than that of SOD. The inhibitory effects of SOD and the two other copper-containing compounds could be abolished by potassium cyanide and reduced glutathione as far as by gomologous cytosol. Catalase failed to effect the RNA release. Although serum albumin itself did not affect release of RNA it was capable to abolish the inhibitory effects of Cu2+ and of copper-tyrosine, but not that of SOD. Possible mechanisms for the inhibitory effect of SOD on RNA transfer across the nuclear envelope are discussed.


Microbiological oxidation of methane in freshwater lakes of the Mari ASSR. The quantity of methane-oxidizing microorganisms and intensity of microbiological methane oxidation in lakes of the Mari ASSR were studied. Maximum numbers of bacteria and highest intensity of methane oxidation were observed during summer stagnation in the thermocline, at the interface of aerobic and anaerobic zones. The intensity of oxidation was 4.6--28.1 x 10(-10) cm3 of methane per day per viable cell. During winter stagnation, the intensity of methane oxidation per cell was an order of magnitude lower. Over 69% of oxidized methane carbon was detected in extracellular metabolites, primarily CO2.


[Role of monovalent cations in protein-lipid interaction in chloroplast membranes]. Role of monovalent cations in chloroplast membranes was investigated using chlorophyll a as an endogenous fluorescent probe. It is found using specific membrane modification by trypsin and lipophylic polypeptide, gramicidin S, that cations cause changes in the chlorophyll microenvironment. The mechanism of these changes is suggested to be an induction of the protein conformational ability, which results in the rearrangement of their lipid environment and in the differentiation of the latter.


Age changes in the fatty acid composition of the lipids of certain actinomycetes. The composition of the fatty acids of the total lipids and its changes during culturing of Act. fluorescens, Act. globisporus, Act. viridis, Act. roseoflavus var Act. roseofungini and two of its proactinomycetes-like variants, were studied. The qualitative composition of the fatty acids of all the strains studied did not differ; the assortment of acids contained 11 basic components: C14-C18 acids-saturated, with normal, iso, and anteiso structures, and monoenic of normal structure. As the mycelium grows, the age dynamics of the fatty acids in submerged culturing are characterized by an increase in the total of saturated branched acids and a decrease in the total number of unsaturated acids. In the case of surface culturing, this tendency is maintained for vegetative cells; when aerial mycelium appears, the sum of the two components mentioned is unchanged. The level of normal saturated acids is constant.


[Characteristics of lactate dehydrogenase isoenzymes of loach differentiated tissues and eggs]. The degree of inhibition by pyruvate, oxalate and urea was determined for the lactate dehydrogenase (EC 1.1.1.27) of some tissues of adult loach (Misgurnus fossilis) and for the lactate dehydrogenase isozymes, which were resistant to the inhibition by AgNO3 and dominated by their activity in the unfertilized eggs of the investigated species. It was found that the skeletal muscle lactate dehydrogenase was not sensitive to the pyruvate excess, but was inhibited by high concentrations of urea and in lower degree by oxalate. The heart muscle lactate dehydrogenase was inhibited by the substrate but only at high concentrations of the last. The main part of the eggs' lactate dehydrogenase was not sensitive to the urea, but it was very sensitive to oxalate and pyruvate. The liver lactate dehydrogenase was inhibited by urea and oxalate in the higher degree than the skeletal muscle enzyme, but after the heat inactivation of the main liver-specific isozyme the differences between them became insignificant. The skeletal muscle lactate dehydrogenase had the lower pH optima than the investigated group of the eggs isozymes. The subunit structure of the lactate dehydrogenase isozymes of different loach tissues and eggs is discussed.


[Effects of uncouplers on the phospholipid composition of mitochondria]. A decrease in the level of lysocardiolipin and lysophosphatidylethanolamine in mitochondria induced by chlorophenacyl and 2,4-dinitrophenol was demonstrated. The effects of the uncouplers were especially well-pronounced under conditions of mitochondrial swelling. It was found that the phospholipase inhibitor nupercain completely reverses the effects. The data obtained suggest that 2,4-dinitrophenol and alkylating compounds increase the phospholipase activity of mitochondria under given experimental conditions.


[Has the respiratory chain of Micrococcus lysodeiktocus any redox components on the outer surface of cytomembrane?]. M. lysodeikticus protoplasts have catalyzed the reduction of 5.10(-4) M ferricianide by endogenous substrates if the respiratory chain is inhibited by cyanide or anaerobiosis. A disturbance of the protoplast permeability by osmotic shock or Triton X-100 treatment resulted in the decrease of the endogenous ferricianide reduction rate and in simultaneous stimulation of malate ferricianide reductase activity in dehydrogenase site of the inner membrane surface. Reactivation of endogenous ferricianide reduction by protoplasts and the loss of malate stimulating activity were observed in hyperosmotic medium. Unlike malate oxidation by osmotically shocked protoplasts, endogenous protoplast repiration was resistant to ferricianide 5.10(-4) M). The latter, being added to protoplasts, induced the oxidation of anaerobically reduced cytochromes b556+560, and it practically did not affect cytochromes c552 and a601. The data obtained suggest that at least one of the respiratory chain components is arranged on the outer side of the protoplast membrane. This component is probably located in the cytochrome region. The results obtained confirm the hypothesis on transmembrane organization of the respiratory chain in M. lysodeikticus.


[Effect of freezing-thawing on the lipid composition of mitochondria]. The effect of near- and subzero temperatures on alterations in the lipid composition of albino rat liver mitochondrial membranes has been studied. Low temperature effect has been shown to intensify peroxide processes and to activate A2 phospholipase in mitochondrial membranes. This is followed by the decrease in lecithin, ethanolaminophosphatide, cardiolipin and cholesterol contents as well as by the accumulation of free fatty acids in the different temperature regions. The dependence of lipid mitochondrial membrane modification intensity on freezing and rewarming rates has been determined.


[Regulation by insulin of the activity of aminoacyl-tRNA synthetases in intact and denervated rabbit muscles]. The activities of Val-tRNA synthetase and Ala-tRNA synthetase in the intact rabbit M. soleus are considerably higher than those in the lateral portion of the intact M. gastrocnemius. The rates of tRNA aminoacylation by the enzymes from both denervated muscles were levelled out 35 days after sciatic nerve section. Insulin injections or diabetes did not significantly influence the aminoacyl-tRNA formation catalyzed by aminoacyl-tRNA synthetases (ARS-ases) from intact muscles. Insulin substantially increased (while diabetes decreased) the activity of both enzymes in the denervated muscles. The results obtained show that the deprivation of striated muscles of trophic nervous influence results in an increase of their sensitivity to the effect of insulin on the activity of aminoacyl-tRNA-synthetases.


[Kinetic properties of the alpha-ketoglutarate dehydrogenase complex from pigeon breast muscle]. A complex kinetic behaviour of the alpha-ketoglutarate dehydrogenase component isolated from the pigeon breast muscle alpha-ketoglutarate dehydrogenase complex was established. The dependence curve of the reaction rate versus substrate concentration has an intermediate plateau and a maximum. The shape of the kinetic curve and specific activity depend on the enzyme concentration both in the reaction mixture and in the original solution of enzyme. The kinetic pattern of isolated alpha-ketoglutarate dehydrogenase suggests that the enzyme is a multi-step dissociating system characterized by different rates of oligomeric forms interconversions at various steps of dissociation. It is assumed that the process of alpha-ketoglutarate dehydrogenase oligomerization is a cooperative one. The kinetic behaviour of the complex and its constituent alpha-ketoglutarate dehydrogenase component is characterized by the same type of the v + [S] dependence curves as is the isolated enzyme. The correlation between the kinetic properties of the enzyme complex and its alpha-ketoglutarate dehydrogenase component and the kinetic behaviour of free alpha-ketoglutarate dehydrogenase suggest that the association-dissociation processes which are probably typical for the component within the complex determine the kinetic behaviour of the complex to a large extent. It is assumed that the anomalous kinetic behaviour of the alpha-ketoglutarate dehydrogenase component is due to the cooperative effects during substrate binding, which are mediated by a shift in the equilibrium between the oligomeric forms of enzyme.


Anticipatory HR deceleration as a function of perceived control and probability of aversive loud noise: a deployment of attention account. Five groups of 10 undergraduate subjects each participated in an experiment to examine the effects of perceived control over, and the probability of occurrence of, noxious (white-noise) stimulation on anticipatory heart rate (HR) deceleration. All groups performed an arithmetic task, the numbers for which were changed on each of the 20 trials, but three groups were defined as active groups since they were instructed that the occurrence of noxious stimulation was contingent upon their performance on the task. The actual probability of occurrence of noxious stimulation (i.e., either 0.9, 0.5 or 0.1) was manipulated between these three groups. A fourth (passive) group (0.5 probability of occurrence) was instructed as to the non-contingent relationship between performance and the aversive white noise. The last group was a control group which only performed the task, and thus both provided an estimate of the rate of return to baseline following the expected HR acceleration to the task and eliminated the need for a within-subject control period to assess HR deceleration. The results indicated that all active and passive groups produced significant HR decelerations, relative to the control group, prior to the noxious stimulus. However, all active groups (regardless of probability levels) displayed significantly greater, and required more trials to maximally develop, anticipatory deceleration than the passive group. In addition, the results for the active groups revealed a direct relationship between the probability of occurrence of noxious stimulation and the magnitude of anticipatory deceleration. It is argued that the results cannot be adequately accommodated by the preparatory-adaptive-response theory. A deployment-of-attention account is suggested since it appears both to account for the obtained pattern of results completely and to generate additional testable predictions for the future.


A new anti-cancer principle isolated from Gymnosporia rothiana Laws, and its use in attaining cures in L1210 leukaemia in combination with "S" phase sensitive drugs. A new anti-cancer drug, code named GCE pending chemical characterization, has been isolated from a plant Gymnosporia rothiana, Laws. In addition to exhibiting good anti-cancer activities, GCE prolongs the "S" phase of cell cycle. This property has been exploited in evolving a new combination chemotherapy schedule with "S" phase sensitive drugs. Cures in L1210 bearing mice have been observed by administering GCE 2 hours prior to administration of "S" phase sensitive drug such as cytosine arabinoside (Ara-C), hydroxyurea (HU) or 5 fluorouracil (5FU).


Biosynthesis and subcellular localization of histamine in H-110 lymphoma. The histidine decarboxylase activity has been studied in the H-110 Lymphoma implanted in Balb-c mice. The enzymatic activity has been determined using DL-Histidine 1-14C by measuring the I--14CO2 liberated during the incubation. It has been found that the histidine decarboxylase activity in the tumor is the highest of the studied tissues. The pretreatment for 5 days with two cytostatic drugs, cyclophosphamide and 5-fluoruracile, determined a decrease of the enzymatic activity in the tumor of 33 and 54 per cent, respectively. This effect has not been observed in the lung. The pretreatment of the animals during 10 days with 0.1 mg per kg body of histamine, which in other experimental tumors induces an increase of the endogenous content of histamine, produces a decrease of the tumoral histidine decarboxylase activity. The histamine-14C uptake was not modified by this pretreatment. The subcellular localization of the radioactivity after pretreatment with histamine-14C evidenced that the nuclear fraction of the tumor contained between 2 and 10 times the radioactivity of other tissues of the same animal.


Routine analysis of multiple steroid receptors in human breast cancer.--I--Technological features. The technological features of multiple and simultaneous assays of steroid receptors (estrogen and progestagens) have been considered in human mammary carcinomas. Most of the parameters involved in the accuracy and the fiability of S-R determination have been investigated : the stability of S-R proteins (collection and storage of sample, cytosol preparation and buffer components, endogenous steroid problem), the specificity and precise quantitation of the binding (conditions of incubations, use of steroid analogs, dextran-coated charcoal method and treatment of binding data by the Scatchard analysis), the identification of the binding (vertical sucrose density gradients) and the interferences in DCC assays. The routinely adopted protocol has been experienced in 650 cases of S-R assay. It is concluded that when performed under appropriate and properly controlled conditions and even in a small sample, multiple S-R assay could result in a precise quantitation and identification of the pathological state of the S-R system in a tumor at time of surgery. Considered with regards to actual knowledges in cell biology, that is of importance and could provide even more information about therapeutic guidance.


The thymol turbidity test and determination of serum cholesterol : two tests to abandon in the routine evaluation of liver function. The thymol turbidity test (Macglan's test) and the determination of serum cholesterol are still performed routinely as liver function tests in many laboratories. In this report, we have employed quantitative methods in order to evaluate the real usefulness of these two parameters. In a first step, the value of the thymol test and of cholesterol determination for the discrimination of the 13 most frequent hepato-biliary diseases was studied by analysis of variance, and compared to that of the following tests : serum bilirubin, serum glutamic pyruvic transaminase, serum alkaline phosphatase serum protein electrophoresis and prothrombin time. It was found that of all these parameters, the thymol test and cholesterol measurement had the lowest discriminatory powers. In a second step, the consequences of the suppression of the two tests were examined by linear discrimination analysis, which was done for all the possible pairs of diseases. It appeared that in each case, the loss of information due to the elimination of the thymol test or of cholesterol determination was nil or negligible. We conclude therefore that the thymol turbidity test and determination of serum cholesterol should be abandoned as routine tests of liver function.


Immunological and plasma protein changes in cancer patients following a single plasmapheresis. Serial serum protein determinations and immunological monitoring were performed prior to and following a single 4 to 5 liter plasma exchange in 10 patients with disseminated cancer. The most consistent changes were observed for two initially elevated alpha globulins, acid glycoprotein and haptoglobin, which declined rapidly in all patients 1 hour after plasmapheresis and began to rise again as early as 24 hours post-plasmapheresis to reach initial levels by 72 hours. Among the immunological parameters T and B cell counts, and phytohemaglutinin-induced lymphocyte transformation showed little change. In 4 out of 10 patients C3 levels dropped at 1 hour post-plasmapheresis and continued to decline to 24 hours, suggesting that consumption of C3 possibly by macrophages may have occurred. In view of our earlier reports that repeated plasmapheresis induced partial tumor regressions in patients with disseminated cancer and that these regressions may have been related to depletion of immunosuppressive serum proteins, it is suggested that to maintain levels of these rapidly renewed proteins at a minimum for as long as possible, it is most appropriate to perform plasmapheresis every 48 hours rather than every 72 or 96 hours as was the case in the earlier study.


Salivary immunoglobulins in progressive systemic sclerosis. A study of salivary immunoglobulins revealed the presence of IgM in 11 out of 17 patients suffering from progressive systemic sclerosis. The presence of IgM was frequently accompanied by an increase in IgA and less often by IgG. Immunofluorescence examination of labial biopsies showed comparable modifications in the immunocyte populations; the presence of IgM cells, sometimes in large numbers, and an increase in IgA and IgG cells. All patients with a nodular lymphoplasmocyte infiltration of the minor salivary gland of the lip have salivary IgM. The presence of IgM in the saliva is a diagnostic criteria of Sjögren's syndrome. The absence of a correlation between immunoglobulin concentrations in the saliva and the serum and correlation between the salivary IgM concentration and the number of IgM immunocytes, demonstrate that the presence of IgM is related to the glandular synthesis of this enzyme.


Carnitine prevention of adriamycin toxicity in mice. Carnitine, a naturally occurring nontoxic compound which aids the myocardial cell in efficiently meeting energy requirements, has been evaluated as a possible protective agent against acute and chronic adriamycin induced mouse toxicity. We have shown that carnitine treatment significantly decreases both acute high dose and chronic, intermittent, low dose adriamycin associated lethality in normal mice. These protective effects are accomplished without decreasing adriamycin anti-tumor activity or increasing bone marrow toxicity.


Surface morphology and ultrastructure of isolated hepatic Kupffer and endothelial cells. Isolated non-parenchymal cells from the rat liver were separated by centrifugal elutriation into two fractions containing structurally intact Kupffer and endothelial cells with purities of over 90% in both fractions. These two cell types were then examined by transmission and scanning electron microscopy. It is concluded that Kupffer and endothelial cells are readily distinguished under the scanning electron microscope on the basis of their different surface features. Kupffer cells show ridges and ruffles while endothelial cells have microvilli and blebs and lack ruffles. As in earlier studies, transmission electron micrographs show that Kupffer cells are larger, have a smaller nucleus--cytoplasm ratio and contain lysosomes while endothelial cells are smaller, have a higher nucleus-cytoplasm ratio and show extensive sieve-plates and fenestrations.


Inhibition of the development of the mammary glands of mice with a bromotriphenylethylene. Administration of a bromotriphenylethylene to C3H/f(XVII/G) female mice implanted with a pituitary under the kidney capsule produces with high doses (200 mg/kg or 20 mg/kg of diet) a strong inhibition of the development of the mammary glands. With a low dose (2 mg/kg) no inhibition was observed. In mice which received the high doses no hyperplastic alveolar nodules were observed. The activity of the compound is more pronounced after 50 days than after 25 days.


Atrioventricular dissociation.

Atrioventricular dissociation. Examination of the scalar ECG usually allows accurate identification of the various types of AV block. Meticulous attention to waveform identification and careful measurement are the essentials in this as in other fields of electrocardiography. In difficult cases, or where the defect is intermittent, additional recording techniques or special manoeuvres may be necessary. Modern techniques including multichannel ambulatory monitoring, stress testing, physiological and pharmacological manoeuvres, and recording of special surface and intracardiac ECGs are occasionally necessary.


Mutation and disease in man.

Mutation and disease in man. Efforts to evaluate the burden of genetic disease maintained by mutation pressure are reviewed. Various individuals and committees have suggested that approximately 1800 per 100,000 liveborn infants will ultimately exhibit clearly defined disease due to chromosomal or point mutation. Direct estimates of human chromosomal and point mutation now permit the identification of about 370 per 100,000 liveborn infants with defect due to mutation in the preceding generation. Recent technical advances permit the study of mutation to shift to the protein level. In Amerindians, mutations resulting in electrophoretic variants of a series of proteins of the blood serum and erythrocyte occur at at rate of 1.6 x 10(-5)/locus/generation. While it is debatable what proportion of electrophoretic variants result in impaired health as heterozgotes or homozgotes in man, we are increasingly aware of disease due to an absence of enzyme or receptor protein due to homozygosity for "null" alleles.  A conservative calculation of the possible impact of these "null" mutations on health proceeds as follows: if the rate of mutation to electrophoretic variants in man is only 1.0 x 10(-5)/locus/generation, and if in man the ratio of nulls to electrophoretic variants is only 2:1 rather than 5:1 of Drosophila, then null mutants with respect to protein should be 2.0 x 10(-5)/locus/generation. There are perhaps 5,000 proteins in man whose absence can lead to disease. It is clear we are just beginning to recognize a class of mutations whose impact on health in toto may exceed the commonly visualized gross phenotypic abnormalities. However, many of the conceptuses homozygous for these null mutations may be eliminated in utero and not come to clinical attention.