In vitro transcription of the tryptophan operon in isolated bacterial nucleoids. In vitro transcription of the trp operon in isolated nucleoids from Escherichia coli was studied. RNA synthesis in this system occurred primarily as a continuation of transcription which had been initiated in vivo; little or no initiation of new RNA chains was observed. Transcription of the trp operon in nucleoids by endogenous RNA polymerase procedded efficiently and ceases sequentially in the order of the gene sequence within the operon. Under these conditions, no appreciable exonuccleolytic digestion of nascent 3H-RNA was found, though some endonucleolytic cleavage was generally seen. Little or no incorporation of 14C-leucine into polypeptides was observed, inspite of tha fact that considerable number of ribosomes and nascent RNA chains were found attached to the isolated nucleoids. The synthesis of trp mRNA continued in the presence of chloramphenicol or fusidic acid, or under conditions where the rebosomal translocation factor G was inactivated. From these and other kinetic studies of trp mRNA synthesis in nucleoids obtained from nonsense strong polar mutants of the trp operon, it was shown that transcription in nucleoids was not connected functionally with transloational processes and thus unable to exhibit polarity effected by a nonsense mutation or by general translational blockage. In studies employing nucleoids from nonsense strong polar mutants of the trp operon, it was demonstrated that RNA polymerase are scantily distributed over the region downstream from the nonsense mutation site of the operon, thereby supporting a notion that in vivo transcription is eventually terminated near the nonsense mutation.


Genetic analysis of mutants from Escherichia coli K12 unable to grow anaerobically without exogenous acceptor. The ana mutation leads E. coli to need an exogenous electron acceptor for anaerobic growth. The affected gene maps near 26 min between chl C and tdk on the chromosome of the organism.


Temperature-sensitive mutants of the slime mould Physarum polycephalum. I. Mutants of the amoebal phase. A replica plating method for isolating it amoebal mutants of Physarum polycephalum has been devised. Temperature-sensitive mutations occur at a frequency after nitrosoguanidine mutagenesis of 10(-3) per survivor, are stable but are not usually expressed in the plasmodia formed from these amoebae in clones. Some of these mutants appear to be cell-cycle stage specific.


Temperature-sensitive mutants of the slime mould Physarum polycephalum. II. Mutants of the plasmodial phase. Methods are described for the isolation and testing of temperature-sensitive plasmodial strains of Physarum polycephalum. Nineteen temperature-sensitive strains were found by screening plasmodia derived from mutagenised amoebae and the properties of these are described. A scheme is outlined for the detection of specific mitotic cycle lesions amongst temperature-sensitive strains, and the properties of a presumptive mitotic cycle mutant are described.


Cloning of calf thymus satellite I DNA in Escherichia coli. The 1400 base pair repeat produced by digestion of calf satellite I DNA (phi = 1.714 g/cm3) with EcoRI, was cloned in E. coli. The hybrid plasmid (pGM 214) which contains the ColE1-Ap vector (pSF 2124) and the 1400 base pair fragment replicates stably in E. coli and can be amplified by chloramphenicol treatment. No clone was found in which more than one "repeat unit" of the satellite I DNA was present in the chimaera plasmid. Digestion of the original satellite I and the plasmid pGM 214 with R-SmaI shows that the satellite DNA replicated in E. coli is cleaved by the restriction endonuclease SmaI whereas the original satellite I DNA from calf thymus is not, suggesting that the satellite I contains a large amount of modified cytosine or guanosine, probably 5-methyl-cytosine. R-EcoRI* produces a number of fragments with the satellite I in the range of 300 base pairs to 1400 base pairs. A physical map of pGM 214 (and pSF 2124) with R-EcoRI, R-HincII, R-HindIII, R-SmaI, R-BamI and R-EclI was constructed. The 1400 base pair "repeat unit" in the pGM 214 is efficiently transcribed in vitro by purified RNA polymerase, starting from a pSF 2124 promoter. The restriction enzyme EclI produces a 350 base pair repeat with calf satellite II (phi = 1,722 g/cm3), whereas the satellite I is not cut by this enzyme.


Assembly of the mitochondrial membrane system. XVIII. Genetic loci on mitochondrial DNA involved in cytochrome b biosynthesis. 1. Fourteen cytoplasmic mutants of Saccharomyces cerevisiae with a specific deficiency of cytochrome b have been studied. The mutations have been shown to occur in two separate genetic loci, COB 1 and COB 2. These loci can be distinguished by mit- X mit- crosses. Pairwise crosses of cytochrome b mutants belonging to different loci yield 4-6% wild type recombinants corresponding to recombinational frequencies of 8-12%. In intra-locus crosses, the recombinational frequencies range from 1% to less than 0.01%. The two loci can also be distinguished by mit- X rho- crosses. Twenty rho- testers have been isolated of which ten preferentially restore mutations in COB 1 and ten others in COB 2. 2. The COB 1 and COB 2 loci have been localized on mitochondrial DNA between the two antibiotic resistance loci OLI 1 and OLI 2 in the order OLI 2-COB 2-COB 1-OLI 1. The results of mit- X mit- and mit- X rho- crosses have also been used to map the cytochrome b mutations relative to each other. The maps obtained by the two independent methods are in good agreement. 3. Mutations in COB 1 have been found to be linked to the OLI1 locus in some but not in other strains of S. cervisiae. This evidence suggests that there may be a spacer region between the two loci whose length varies from strain to strain. 4. Two mutations in COB 2 have been found to cause a loss of a mitochondrial translation product corresponding to the cytochrome b apoprotein. Instead of the wild type protein the mutants have a new low-molecular weight product which is probably a fragment of cytochrome b. The fact that the mutations revert suggests that they are nonsense mutations in the structural gene of cytochrome b.


Suppression of temperature-sensitive aminoacyl-tRNA synthetase mutations by ribosomal mutations: a possible mechanism. The biochemical basis of suppression of a temperature-sensitive alanyl-tRNA synthetase (alaS) mutation by mutational alterations of the ribosome has been investigated. Measurement of the polyU-dependent polyphenylalanine synthesis showed that ribosomes from the suppressor strains are less active than ribosomes from the unsuppressed aminoacyl-tRNA synthetase mutant. In this system no increased translational ambiguity could be detected for the suppressor ribosomes. This fact and also the findings that the ram-1 mutation is not able to suppress the aminoacyl-tRNA synthetase mutation and that presence of the suppressor allele is not accompanied by a measureably improved alanyl-tRNA synthetase activity argue against the possibility that suppression might be due to increased translational misreading rates of the alanyl-tRNA synthetase mRNA. It has been further found that partial suppression of temperature sensitive growth of the alaS mutation can be achieved by independent ribosomal mutations leading to reduced growth rates because of a mutation to antibiotic resistance. Addition of low concentrations of a variety of antibiotics acting at the ribosomal level can also partially revert the temperature-sensitive phenotype of the alaS mutant. Although the possibility cannot be excluded that suppression is due to the stabilisation or activation of the mutant enzyme by some indirect effect of the suppressor ribosomal mutations, the following working hypothesis is favoured at the moment: It is assumed that limitation of the aminoacyl-tRNA synthetase activity in a certain range of the restrictive temperature causes growth inhibition by the premature termination of polypeptide synthesis at the ribosome or by the unbalanced synthesis of the individual cellular proteins under this condition. The mechanism of suppression by ribosomal mutations is proposed to consist of the release of this growth inhibition by the reduction of the rate of polypeptide synthesis, which would keep amino acid incorporation from exceeding the slow charging of tRNA and thus exhausting the pool of charged tRNA. In the suppressor strains, therefore, growth at the semi-restrictive temperature is no longer limited by the aminoacylation of tRNA but by the translational process at the mutated ribosome. This influence of the ribosomal mutation on the speed of translation could be directly or indirectly coupled with an effect on translational fidelity resulting in the prevention of the binding of uncharged or non-cognate charged tRNA or in the tighter binding of peptidyl-tRNA when cognate aminoacyl-tRNA is limiting.


The use of specialised transducing phages in the amplification of enzyme production. Two types of lambdatrp phages have been used as model systems to investigate ways of optimising the expression of bacterial genes from transducing phage genomes. Excellent yields of trp enzymes were achieved by infecting a trpR- host with Q- or Q-S- derivatives of lambdatrpAM1, which expresses its trp genese exclusively from the trp promoter. The five trp geneproducts constituted more than 50% of the total soluble protein of infected cells under these conditions, and an even higher proportion of the protein synthesized after infection. In a trpR+ host, phage DNA replication was easily able to override tryptophan-mediated repression by titration of the trp promoter were equally productive, while having the advantage of being much simpler to construct and propagate. lambdatrp phages lacking the trp promoter were used to investigate ways of optimising gene expression initiated at the phage promoter, PL. Though very powerful, the latter promoter is more difficult to harness then the trp promoter. Derepression of transcription from PL by the use of cro- mutations is accompanied by poor replication of transducing phage DNA. Attempts to circumvent this difficulty using virulent of cro,cII double mutants have not been successful. Nevertheless, cells infected with a lambdatrp phage expressing its trp genes exclusively from PL made up to 16 per cent of their protein as trp gene-products.


Recombined molecules of mitochondrial DNA obtained from crosses between cytoplasmic petite mutants of Saccharomyces cerevisiae: the stoichiometry of parental DNA repeats within the recombined molecule. We have studied recombination between repetitive mitochondrial DNAs from cytoplasmic petite mutants of Saccharomyces cerevisiae. Mitochondrial DNA was isolated from two parental p- mutants, carrying respectively the CR and the ER mitochondrial genetic markers, and from two p- CRER diploid genetic recombinants. These two recombinants, obtained from the same parental petites, differ in their degrees of suppressiveness. The p- mitochondrial DNAs were analyzed by DNA-DNA hybridization, high resolution melting and reassociation kinetics. It was found that the repeating unit of the CR parental p- DNA is 3 to 4 times longer than that of the ER parent. There is very little sequence homology between these two p- mitochondrial DNAs and almost all parental sequences are integrated into the recombined molecules. Mitochondrial DNA from both types of recombinants seems to contain the two parental repeating units in the ratio 1:1.


Gal mRNA initiated within IS2.

Gal mRNA initiated within IS2. A strain of E. coli carrying IS2 in the control region of the gal operon has been found to revert to a constitutive phenotype. These revertants can be divided into two classes, which differ in their rate of enzyme synthesis and gal transcription. One revertant synthesizes the gal messenger at a low level (low level revertants), the other at a higher level that exceeds that of the induced wild type two- to three-fold (high level revertants). In both cases it has been shown that the gal messenger is covalently bound to IS2-RNA, which is transcribed from IS2 in the original orientation. The evidence suggests, that the section of the IS2-element, from which this RNA is transcribed in the case of the high level revertants is smaller than 50 nucleotides long: i.e. the resolution of the hybridization method used for the detection of sequence homologies exceeds that of the electron microscopical heteroduplex technique.


E. coli membranes become permeable to ions following T7-virus-infection. Infection of E. coli with the viruses T7 or T3 leads to a dramatic efflux of potassium ions. This ion efflux is caused by the virus particle since no concomitant protein synthesis is required. T7 mutants carrying deletions in the M-gene (Schweiger et al., 1975), however, yield virus particles disturbed in the ion release.


REPLICAtion of small plasmids in extracts of Escherichia coli: requirement for both DNA polymerases I and II. The role of the three E. coli DNA polymerases (pol I, II, and III) in the replication of Col E1 DNA and other small plasmids with similar replicative properties was investigated in a soluble in vitro system prepared by freeze-thaw lysis of chloramphenicol-treated cells (Staudenbauer, 1976). Extracts from isogenic mutants of the polA, polB and polC gene loci deficient in pol I, II, and III respectively were examined for their replicative capacity. It was found that polA and polC extracts are deficient in the synthesis of supercoiled plasmid DNA, whereas the polB mutation has not effect. Deficient extracts could be complemented by addition of purified pol I and pol III holoenzyme. Analysis of the in vitro synthesized DNA by alkaline gradient centrifugation indicates that pol I is involved in an early step of the replication cycle whereas pol III is required at a later stage. These conclusions are confirmed by inhibition studies employing arabionsylcytosine triphosphate (aCTP) which is shown to interfere with pol III as well as pol II. The strong inhibitory effect of aCTP on plasmid replication is not influenced by the polB mutation and mimicks the effects of thermal inactivation of polC extracts. It is suggested that aCTP blocks plasmid ENA replication in vitro by interfering with pol III function


Genetic studies of the ribosomal proteins in Escherichia coli. X. Mapping of the ribosomal proteins, L21 and S15, by intergeneric mating experiments between Serratia marcescens and Escherichia coli K12. Episomes of E. coli, which cover argG but not the str region, were transferred to Serratia marcescens. Ribosomal proteins from these hybrid strains were analyzed with phospho-cellulose or carboxy-methyl-cellulose column chromatography. Two E. coli ribosomal proteins, L21 and S15, could be detected in the ribosome from the hybrid strains in addition to the ribosomal proteins of S. marcescens.


Formation of NADPH-nitrate reductase activity in vitro from Aspergillus nidulans niaD and cnx mutants. Mutants of A. nidulans at several loci lack detectable NADPH-nitrate reductase activity. These loci include niaD, the structural gene for the nitrate reductase polypeptide, and five other loci termed cnxABC, E, F, G and H which are presumed to be involved in the formation of a molybdenum-containing component (MCC) necessary for nitrate reductase activity. When forzen mycelia from A. nidulans deletion mutant niaD26 were homogenized in a Ten Broeck homogenizer together with frozen mycelia from either cnxA6, cnxE29, cnsF12, cnxG4 or cnxH3 strains grown on urea + nitrate as the nitrogen source, nitrate reductase activity was detectable in the extract. Similar results were obtained by co-homogenizind niaD mycelia with Neurospora crassa nit-1 mycelia induced on nitrate. Thus, all A. nidulans cnx mutants are similar to the N. crassa nit-1 strain in their capacity to yield NADPH-nitrate reductase in the presence of the presumed MCC. As judged by the amounts of nitrate reductase formed, niaD26 mycelia grown on urea +/- nitrate contained much more available MCC than ammonium-grown mycelia. No NADPH-nitrate reductase activity was found in extracts prepared by co-homogenizing mycelia from all five A. nidulans cnx strains. Wild-type A. nidulans NADPH-nitrate reductase acid dissociated by adjustment to pH 2.0-2.5 AND RE-ADJUSTED TO PH 7 could itself re-assemble to form active nitrate reductase and thus was not a useful source of MCC for these experiments. These results are consistent with the conclusion that the active nitrate reductase complex is composed of polypeptide components which are the niaD gene product, plus the MCC which is formed through the combined action of the cnx gene products. Further, the production of MCC may be regulated in response to the nitrogen nutrition available to the organism.


Genetic and biochemical studies on mannose-negative mutants with colonial morphological alterations. Four mannose mutants of Saccharomyces cerevisiae are described. In addition to their inability to grow on mannose as sole carbon and energy source, the mutants exhibit a distinct colonial morphological alteration. The isolates form hard colonies when grown on agar and exhibit extreme flocculation in broth. These organisms can catabolize mannose, but only form one-half the mannan found in the wild-type yeasts.


Revertants from RNase III negative strains of Escherichia coli. E. coli strains carrying the rnc-105 allele do not show any level of RNase III in extracts, grow slower than rnc+ strains at temperatures up to 45 degrees C and fail to grow at 45 degrees C. Revertants which can grow at 45 degrees C were isolated. The vast majority of them still do not grow as fast as rnc+ strains and did not regain RNase III activity. The mutation(s) which caused them are suppressor mutations (physiological suppressors) which do not map in the immediate vicinity of the rnc gene. A few of the revertants regain normal growth, and contain normal levels of RNase III. They do not harbor the rnc-105 allele and therefore are considered to be true revertants. By using purines other than adenine it was possible to isolate rnc + pur- revertants from an rnc- pur- strain with relative ease. They behaved exactly like the true rnd+ revertants isolated from rns- strains at 45 degrees C. A merodiploid strain which contains the rnc+ gene on an episome behaves exactly like an rnc+ strain with respect to growth and RNA metabolis, eventhough its specific RNase III activity is about 60% of that of an rnc+ strain; thus the level of RNase III is not limiting in the cell. The rnc- strains show a characteristic pattern of transitory molecules, related to rRNA, 30S, 25S, "p23" and 18S, which are not observed in rnc+ strains. This pattern is unchanged in rnc- strains and in the revertants which are still lacking RNase III, regardless of the temperature in which RNA synthesis was examined (30 degrees to 45 degrees C). On the other hand, in the rnc+ strains as well as in the true revertants and the rnc+/rnc- merodiploid, the normal pattern of p16 and p23 is observed at all temperatures. These findings suggest that all the effects observed in RNase III- strains are due to pleiotropic effects of the rnc-105 allele, and that the enzyme RNase III is not essential for the viability of the E. coli cell.


Identity of a gene responsible for suppression of aminoacyl-tRNA synthetase mutations with rpsT, the structural gene for ribosomal protein S20. Sepcialized transducing lines of phage lambda carrying segments between thr and car from the E. coli chromosome have been isolated. With help of these phages it has been shown that the gene sups20 (Böck et al., 1974) corresponds to rpsT, the structural gene for ribosomal protein S20.


Anomalies in the selection of mutants of Schizosaccharomyces pombe resistant to 8-azaguanine. Anomalies in selection render 8-azaguanine unsuitable as a selective agent for screening forward mutations in continuour cultures of Sch. pombe. This system may, however, provide tha basis for an enrichment method for the simultaneous isolation of mutants at two loci.


Further evidence for the participation of proteins S 3, S 14 and S 19 in tRNA binding to E. coli 30 S subunits. Previous studies have shown that iodination of 30 S subunits causes inactivation for both enzymatic fMet-tRNA and non-enzymatic phe-tRNA binding activities. This inactivation was shown to be due to the modification of three to five ribosomal proteins [1]. In this report the role of these proteins in tRNA binding activity has been further studied. Purified ribosomal proteins, isolated from modified subunits, are re-assembled into otherwise unmodified 30 S ribosomes and assayed for tRNA binding capacity. The presence of modified S 3, S 14 and S 19 (S 15) in the reconstituted particle results in substantial reduction of both fMet-tRNA and phe-tRNA binding activities. This reduction in tRNA binding activity does not appear to be due to an assembly defect.


Ribosomal protein as substrate for a GTP-dependent protein kinase from yeast. A protein kinase specific for casein and acidic ribosomal proteins was isolated and partly characterized. It was found that the enzyme utilizes GTP and ATP as phosphoryl donors. Its affinity for ATP was considerably higher than for GTP with the km values of 7.6 X 10(-6)M and 5.5 X 10(-5)M, respectively. Two-dimensional acrylamide gel electrophoresis revealed the phosphorylation of the same ribosomal proteins with either of the [gamma-32P] nucleotides used. It was also shown that one acidic protein (S1 or S2) of 40 S and two acidic proteins (L2 and L3) of 60 S ribosomal subunits were predominantly phosphorylated in vitro. The phosphorylated proteins: L2 and L3 seem to correspond to the proteins of L7 and L12 of E. coli ribosomes. The isolated kinase phosphorylated several basic ribosomal proteins though to a lower extent than the acidic ones.


Catalysis of the peptide bond formation by 50 S subunits of E. coli ribosomes with N-(formyl) methionine ester of adenylic acid as peptide donor. 50 S subunits of E. coli ribosomes catalyze the reaction of the 2'(3')-N-(formyl) methionine ester of adenosine 5'-phosphate and Phe-tRNA resulting in peptide bond synthesis. Cytidine 5'-phosphate stimulates this process on 50 S ribosomal subunits as well as on intact ribosomes. The obtained data show that the areas of the peptidyltransferase donor site which binds the 3'-terminal fragment of peptidyl-tRNA possess completely formed structures on 50 S ribosomal subunits.


A model of promoter recognition along the two helical grooves of DNA. A speculative model based on published sequences to explain the specific binding of RNA polymerase of E. coli to promoters is suggested: (see article). A fragment 24 base pairs long to the left of the initiation site must not contain the G's in the positions indicated by the circles and must contain T's (or G's) in the positions marked by the squares. In most known cases mutual disposition of the circle and square patterns is as shown above. In one case (the fd G3 promoter) the pattern of squares is shifted by 4 base pairs to the right relative to the pattern of universal non-G's (circles).


[Our method for routine examination of kidney bioptic material by light, immunofluorescence and electron-microscopy]. Authors describe their own method for the investigation of needle-biopsy of kidney using light-, and electron microscopy and immunofluorescent technique as well. Small pieces are cut from both end of the needle-biopsy-cylinder and are embedded for electron microscopy. From the larger central part of it cryostat sections are made (at -20 degrees C) for the immunofluorescent study. Afterwards the piece of tissue remained can be fixed in formaldehyde and embedded in paraffin for light microscopic investigation. All three methods can be carried out even when having a 6 mm long needle-biopsy specimen.


Mutagenic evaluation of ronidazole.

Mutagenic evaluation of ronidazole. Ronidazole was evaluated for mutagenic potential using in vitro microbial tests and in vivo studies in mice. The microbial test used the histidine requiring mutants of Salmonella typhimurium with and without a rat liver microsomal activation system (Ames test). The studies in mice included the dominant lethal test, micronucleus test and cytogenetic assays. Ronidazole was given orally in doses of 50, 100 and 200 mg/kg/day in the in vivo studies. In the dominant lethal test, groups of male mice were treated for five consecutive days before being mated with untreated females. In the micronucleus test, the mice were administered the compound for 2 or 5 consecutive days; they were killed 6 h after the last dose and bone marrow was examined for the presence of micronuclei in developing erythrocytes. In the cytogenetic assays, bone marrow cells in metaphase were examined for chromosome aberrations, 6, 24 and 48 h after mice were treated acutely with the test compound. In addition, similar examinations of chromosomes were made on mice given five consecutive dosages of ronidazole and killed 6 h after the last dose. The results of the various in vivo studies did not suggest that ronidazole would be mutagenic for the mammal. Ronidazole at concentrations of 10 and 50 mug/plate was found to increase the number of back mutations of missense mutants in the in vitro bacterial test. This finding confirms the results of Voogd et al. [19]. Incorporation of the microsomal activation system had no effect on the mutagenic capability of the test compound. In conclusion, although ronidazole was shown to be mutagenic in in vitro bacterial systems, the in vivo systems did not suggest that the compound would be mutagenic for the mammal.


Mutagenic effect of nialamide on Salmonella typhimurium. The mutagenicity of an antidepressant drug, nialamide, was studied with Salmonella typhimurium TA1535-8. Nialamied was mutagenic for strain TA1535 in the absence of rat liver extracts.


Mutagenicity of the food colour brown FK and constituents in Salmonella typhimurium. The food colour Brown FK (EEC Serial No. 124) is a mixture of p-sulphophenylazo derivatives of m-toluylenediamine and m-phenylenediamine and is used in the UK for colouring kippers. Brown FK and its constituents were assayed for mutagenicity in Salmonella typhimurium TA 1535, TA 1537 and TA 1538. Samples of Brown FK from three manufacturers were mutagenic in TA 1538 (framshift mutant) when activated by a rat-liver supernatant fraction. Mutagenicity was linearly dose-dependent in the range of 0--3 mg/plate with activities ranging from 22 to 50 times the spontaneous mutation frequency. One sample of Brown FK was mutagenic in the absence of metabolic activation producing a 16-fold increase in mutation at 4 mg/plate. Two major constituents of Brown FK, 2,4-diamino-5-(p-sulphophenylazo)-toluene (I) and 1,3-diamino-4-(p-sulphophenylazo)benzend (II), each present at about 18% in the complete colour, were mutagenic in TA 1538. Mutagenicity was linearly dose-related in the range 0--1 mumol/plate, with slopes of 0.35 mutants/nmol for compound I and 1.5 mutants/nmol for compound II. This activity was dependent on metabolic activation. Four other major constituents, (di- and tri-substituted diamines) were inactive, as was sulphanilic acid, the major excretion product of Brown FK. The mutagenicity of Brown FK could be largely accounted for by the combined effects of compounds I and II. Earlier studies showed that compounds I and II were responsible for the acute myotoxic effects seen when Brown FK was given per os to rats and pigs. Azoreductive fission of I and II to reactive triamines by gut microflora was thought to be the main metabolic pathway by which Brown FK produced its myotoxic effects, and it is proposed that the mutagenic effects of Brown FK are probably mediated by a similar mechanism.


Mutagenicity of industrial compounds: styrene and its possible metabolite styrene oxide. Styrene and its presumed metabolite, styrene oxide, were tested for their mutagenic effect on a forward mutation system of yeast and of Chinese hamster cells, and on a gene-conversion system of yeast. Experiments with liver microsomal preparations and host-mediated assay with yeast were also carried out. Styrene oxide was mutagenic in all test systems. Styrene was mutagenic only in the host-mediated assay.


The mutagenicity of benzimidazole and benzimidazole derivatives. VI. Cytogenetic effects of benzimidazole derivatives in the bone marrow of the mouse and the Chinese hamster. Methyl benzimidazole-2-ylcarbamate (MBC) was mutagenic in mice by the micro-nucleus test. Other benzimidazole derivatives, with the exception of the parent compound of MBC, benomyl, and the very closely related substance 2-benzimidazolylurea, did not produce micro-nuclei in mouse bone marrow. Evidence is presented that MBC acts through inhibition of mitosis and that for this action the carbamoyl group is a necessary but not a sufficient condition. It is also demonstrated that for this particular type of mutagenic activity a threshold limit exists, which seems to be in the order of less than 10 mug MBC per ml blood.


Dominant lethal studies with paraquat and diquat in male CD-1 mice. The herbicides paraquat and diquat were tested for dominant lethal activity in male CD-1 mice. No mutagenic effects were detected on any stage of spermatogenesis in treated males if these compounds were administered orally up to 4 mg paraquat/kg/body weight/day of 10 mg diquat/kg/body weight/day for 5 days. There was no increase in the number of post-implantation losses as shown by the number of females with one or more early deaths or number of early deaths/pregnancy or the number of early deaths/total implants/pragnancy. There was no evidence of pre-implantation losses as indicated by the total implants/pregnant female. There was no anti-fertility effect on the treated males as measured by the pregnancy frequency or successful mating frequency. The lack of dominant lethal effect was not due to particular insensitivity of the animals used since such effects were amply demonstrated in mice doses orally on 5 days with ethyl methanesulphonate at 100 mg/kg/body weight/day, or intraperitoneally on one day with cyclophosphamide at 200 mg/kg/body weight.


Mutagenicity testing and risk estimation with mammals. Mammalian test systems are currently used for mutagenicity screening. The necessity and the limitations of standardizing these methods are discussed for dominant-lethal assay. In addition to the refinement of standard methods, the development of new systems in mammals is emphasized. One promising approach is the detection of presumed somatic mutations. Another new development takes advantage of electrophoretic methods for detecting induced structural alterations of gene products. Mammalian experiments will be essential for the assessment of risks from chemical mutagens. The development of standards for the controlled use of chemical mutagens should be guided by the experience accumulated in radiation genetics. Two methods, the measurement of specific-locus mutation rates in mice and the direct determination of the phenotypic damage of dominant genes affecting the skeleton of mice, are recommended for the assessment of the hazard of chemical mutagens.


Practical evaluation of mutagenicity data in mammals for estimating human risk. Chrosomal aberrations are known to constitute a significant portion of the genetic risk from practically all mutagenic agents. These effects are diverse in both nature and in the stage of the germ cells' life cycle at which they are produced. Arguments are made pointing out many of the problem areas in our understanding the significance of chromosomal aberrations in relation to genetic risk. Data are summarized that offer explanations as to (1) why so few chromosomal effects are recovered after treating spermatogonial stem cells, (2) how chromosome damage and dominant lethality are correlated when postmeiotic germ-cell stages are treated with MMS, and (3) why so few reciprocal translocations are recovered after irradiation of oocytes.


The utilization of in vitro mutagenesis techniques to explain strain, age and sex related differences in dimethylnitrosamine tumor susceptibilities in mice. The carcinogen dimethylnitrosamine (DMNA) is known to exhibit a high degree of strain, organ, age, and sex related tumor specificity in mice. Using microbial mutagenesis assay coupled with mouse tissue microsomal enzyme activation systems, evidence has been obtained that demonstrated a close relationship between the level of in vitro DMNA activation to a mutagen and in vivo tumor susceptibility. DMNA activation by liver, lung, and kidney microsomes from several mouse strains was compared by measuring the rate of mutagenic metabolites formed during incubation of the carcinogen in mutation assays using Salmonella typhimurium G-46 as the indicator microorganism.


Mutagenicity and DNA-modifying activity: a comparison of two microbial assays. Aspects of the Salmonella mutagenesis and Escherichia coli DNA polymerase deficient (pol A1) assay procedures for detecting environmental mutagens are discussed. The chief limitation of the pol A1-- assay involves substances that do not diffuse rapidly in agar. This problem can be overcome by performing the test in suspension. A simple procedure for accomplishing this is described. Although the Salmonella assay is more flexible, under routine conditions it does not respond to several classes of substances which give positive responses in the pol A1- system. For optimal testing, it is recommended that the two microbial assays be used in tandem. The DNA-modifying properties of povidone-iodine for eukaryotic and prokaryotic cells are described. Even though this substance does not display mutagenic properties in the standard Salmonella assay, it does so in suspension culture. The basis of the mutagenic and DNA-modifying properties of povidone-iodine appears to involve the iodination of the cystosine residue of DNA.


Metabolic studies and the evaluation of genetic risk from the viewpoint of industrial toxicology. In recent years some important industrial chemicals, e.g. solvents, and monomers used in the production of plastics, have been found to be more dangerous than had been suspected. Some of them are mutagens and carcinogens. The active substance may be the compound itself, but more frequently it is a reactive intermediate, an alkylating agent, formed from the parent compound by oxidation under the influence of liver-microsome mixed-function oxidases. Trichloroethylene, vinyl chloride, 1,1-dichloroethylene and 2-chloro-1,3-butadiene can be mentioned as examples, where mutagenic or carcinogenic activity has been demonstrated; similar activity of some others is to be suspected. Metabolic studies may explain unexpected effects or they may allow one to predict such effects. Tests on microorganisms with a metabolic activation in vitro seem to be extremely valuable for fast and efficient screening of man-made chemicals to be introduced into the environment, because such tests combine the use of liver microsomes and bacteria for detection and classification of the effect. Mutagenicity tests in mammals do not lose their usefulness, since thay take into account the distribution of the compound in the body, its transport to the target organ, species-specific differences etc. As exposures of workers to chemicals mentioned above have been quantitatively measured regularly, epidemiological studies should be performed with regard to mutagenic and carcinogenic effects in relation to the degree of exposure. Here is a chance for better understanding of how to extrapolate experimental results to human populations and how to establish safe levels of chemicals in the environment if at all possible and acceptable.


A hierarchical approach to mutagenicity testing and regulatory control of environmental chemicals. A hierarchical approach to mutagenicity testing and regulatory control of environmental chemicals is proposed. The guiding concepts and principles relating to the testing of chemicals for mutagenicity and evaluation of genetic hazards are discussed.


The capacity of Drosophila for detecting relevant genetic damage. For the detection and study of mutagenic agents, Drosophila offers many advantages. It is a higher organism with a short generation time that is cheap and easy to breed in large numbers. The simple genetic testing methods provide unequivocal answers about the whole spectrum of relevant genetic damage. A comparison of the detection capacity of assays sampling different kinds of genetic damage revealed that various substances are highly effective in inducing mutations, but do not produce chromosome breakage effects at all,  or only at much higher concentrations than those required for mutation induction. Of the different assay systems available, the classical sex-linked recessive lethal test thus deserves priority, in view of its superior capacity to detect mutagens. Of practical importance is also its high sensitivity, because a large number of loci in one-fifth of the genome is tested for newly induced forward mutations, including small deletions. Drosophila is capable of carrying out the same metabolic activation reactions as the mammalian liver. An additional advantage, in this respect, is the capacity of Drosophila for detecting short-lived activation products, because intracellular activation occurs within the spermatids ans spermatocytes. These properties make the test for recessive sex-linked lethals a useful tool for verifying results obtained in the pre-screening of potential mutagens with fast microbial assay systems. In studies on non-disjunction, detailed genetic analysis of the induced changes is possible, and these may shed light on the mechanisms involved. A new adaptation of the bithorax transvection method by Mendelson permits the recovery of high yields of chromosome aberrations in a fast one-generation test.


Misrepair of overlapping daughter strand gaps as a possible mechanism for UV induced mutagenesis in UVR strains of Escherichia coli: a general model for induced mutagenesis by misrepair (SOS repair) of closely spaced DNA lesions. It has been previously reported that an inducible form of post-replication repair appeared to be required for UV induced mutagenesis in a uvrA strain of Escherichia coli. It is shown here that the numbers of daughter strand gaps requiring inducible repair were similar to the numbers calculated to be overlapping one another in opposite daughter chromosomes. An estimation of survival with no repair of these gaps resembled the survival predicted with no mutagenesis. It is the thus proposed that inducible post-replication repair causes mutagenesis by the repair of overlapping daughter strand gaps. A general model for induced mutagenesis is presented. It is proposed that (a) some DNA lesions introduced by any DNA damaging agent may be close enough to interfere with constitutive repair replication of each other, (b) these lesions induce a repair system (SOS repair) which involves the recA+ lexA+ and polC+ genes (c) repair and concomitant mutagenesis occurs during repair replication by the insertion of mismatched bases opposite the noncoding DNA lesions.


Effect of excision repair on azide-induced mutagenesis. Azide mutagenesis was investigated in Salmonella typhimurium and Escherichia coli. Azide was highly effective in inducing his+ revertants in excision-repair deficient (uvrB) derivatives of S. typhimurium hisG46 and in inducing high frequencies of 5-fluorouracil resistant mutants in excision-repair deficient (uvrA) derivatives of E. coli B/r WP2. In excision-repair plus strains, azide was only a marginal or ineffective mutagen, demonstrating that the bacterial excision-repair system could repair nearly all azide-induced damage. This observation suggests that the initial azide-induced lesion causes a major DNA helix distortion recognizable by the excision-repair endonucleases. The presence of recombination deficient (recB or recC) genes in combination with uvrA increased E. coli sensitivity to azide killing, but depressed azide mutagenicity. These results are similar to those reported for UV-induced mutagenesis with the E. coli strains and suggest that post-replication repair might be the error-prone step in the repair process. Azide mutagenesis specificity is, however, unique and different from UV, as demonstrated by inability of azide to revert the ochre try locus in E. coli WP2s. These results show that the initial azide-induced DNA damage is highly specific but different from UV-induced DNA damage. Metabolic inhibitors, similar in action to azide, did not induce mutations in S. typhimurium strain TA1530, a strain highly susceptible to azide mutagenesis, thus ruling out the possibility that azide mutagenesis was due to peroxide accumulation. A mechanism based on in vivo activation of azide to the actual mutagen is proposed.


The relation between repair of DNA and radiation and chemical mutagenesis in Saccharomyces cerevisiae. The effect of various genes involved in DNA repair functions on radiation and chemical mutagenesis in Escherichia coli is discussed and compared to similar studies done in yeast. Results of the effect of various genes conferring radiation-sensitivity on mutation induction in yeast are presented and related to current ideas of mutagenesis.


The distribution of fetal death in control mice and its implications on statistical tests for dominant lethal effects. In dominant lethal testing fetal death is generally assumed to follow either a Poisson or binomial distribution. However, both of these models were found to be inappropriate when three large sets of mouse control data and other data sets from the literature were examined. The validity of statistical test procedures based on these inappropriate models was then studied in detail. It was found that chi-square tests (which assume an underlying binomial distribution) may seriously exaggerate the level of significance and hence should not be used. In contrast, the inappropriateness of the underlying Poisson or binomial model appeared to have little effect on the validity of pairwise comparisons by analysis of variance procedures. Unlike chi-square, these procedures regard the pregnant female rather than the individual implant as the experimental unit. However, a statistical analysis of dominant lethal data generally involves more than a series of pairwise comparisons, and it is unclear how an invalid underlying model may affect statistical test procedures in this more complex situation. Moreover, it is difficult to justify the use of statistical models that are demonstrably invalid when a reasonable alternative exists. Thus, until a satisfactory parametric model can be found and appropriate test procedures derived, we prefer to analyze dominant lethal data by non-parametric (distribution-free) methods. Proportion of dead implants per female appears to be a more meaningful measure of fetal death than number of dead implants per female for several seasons which include (1) analyses based on proportions take the total number of implants per female into account and (2) analyses based on proportions make more reasonable assumptions concerning pre-implantation losses and are more powerful when such losses occur. Despite our concern with the appropriateness of the underlying model, in practice we have found few instances in which non-parametric and analysis of variance procedures have led to markedly different conclusions.


Detection of X-ray induced dominant lethal mutations in mice: an in vitro approach. The expression of dominant lethal mutations induced by 450 rad of X-radiation in the germ cells of male mice was detected by an in vitro analysis. Embryos sired by irradiated males had a higher incidence of developmental failures in early cleavage, at the late morula stage, and at the late blastocyst stage due to dominant lethal mutations than did control embryos. Dominant lethal mutations were induced most frequently in germ cells exposed as early spermatids and spermatocytes and next most frequently in germ cells exposed as sperm. A decrease in fertilizations, presumably reflecting cell killing, was found in irradiated spermatocytes. These observations indicate that in vitro analysis permits a more detailed description of mutations that are expressed as preimplantation failures than does in vivo analysis.


The production of micronuclei from chromosome aberrations in irradiated cultures of human lymphocytes. A rapid assay for chromosomal damage would greatly speed studies of the mechanism by which chromosomal aberrations are formed. The characteristics of such an assay--micronuclei produced in cultured human lymphocytes--are given here, together with the evidence that the assay accurately measures X-ray-induced chromosomal damage. Micronuclei arise from chromosomal fragments that are not incorporated into daughter nuclei at mitosis because they lack a centromere. In our experiments the response of lymphocytes from different donors was very uniform and agreed well with what was expected from metaphase analysis of aberrations: (1) the increase in micronucleus frequency begins at the time of the first mitoses, 48 hours after the cultures are started, (2) the exponent of the dose response equation (y=kDn) was 1.2 for micronuclei. For one-hit aberrations n=1 whereas for two-hit aberrations n=2. Since two-hit aberrations predominate in these cultures, a value of n= approximately 1.8 was expected if no increase in mitotic delay or cell death occurred at higher doses, and n less than 1.8 if an increase occurred, (3) the frequency of micronuclei was decreased by a factor of about two when the dose was fractionated, as expected when most of the aberrations are two-hit. The rejoining time for four or five donors was between 30 and 60 minutes, (4) the X-ray-induced micronucleus frequency in cells from people with Down's syndrome (trisomy-21) was twice that of control donors as expected from metaphase analysis [22,23]. Since the micronucleus assay reflects the aberration frequencies so well and is so fast, it is suitable for a rapid assessment of chromosomal damage.


Sister chromatid exchange as an assay for genetic damage induced by mutagen-carcinogens. I. In vivo test for compounds requiring metabolic activation. An in vivo system has been devised in which chemical mutagen-carcinogens injected into an animal induce sister chromatid exchanges that can be observed when the animal's peripheral lymphocytes are subsequently cultured and then stained with the FPG technique. Chemicals requiring metabolic activation, as well as those that do not, produce significant increases in SCE frequency one day after exposure. The frequency then returns to control level within two weeks. This in vivo system is a highly sensitive assay for the ability of chemical agents to damage chromosomes.


Sister chromatid exchange as an assay for genetic damage induced by mutagen-carcinogens. II. In vitro test for compounds requiring metabolic activation. Sister chromatid exchanges (SCE's) which are easily seen by "harlequin chromosome" techniques can be readily induced in cultured Chinese hamster ovary (CHO) cells by low concentrations of mutagen-carcinogens that do not require metabolic activation. If the cells are simultaneously treated with cyclophosphamide which does require metabolic activation before it becomes mutagenic, and an activating system consisting of an extract of rat liver containing microsomes (S-9 Mix) then numerous SCE's are induced by the compound. This indicates that the induction of sister chromatid exchanges in such cells can be used as an in vitro assay for mutagens that require activation as well as those that do not. The method, which is very simple and quick, is more sensitive than is the usual cytogenetic assay in which chromosome aberrations are assayed.


An investigation into the potential of a mammalian temperature sensitive leucyl-tRNA synthetase mutant for mutagenesis studies. Reversion of the mammalian temperature sensitive leucyl-tRNA synthetase mutant CHO tsH1 [33] has been investigated to determine its potential for mutagenesis studies. The protocol for a mutation assay using the new class of temperature sensitive conditional lethal mutants of somatic cells is presented. While it requires careful control of temperature during revertent selection it promises to provide a system complementary to the existing mutation assays. UV and EMS mutagenesis of tsH1 has confirmed that approx. 3TD of expression time are sufficient for complete expression of induced mutants at low mutagen doses (80% survival following UV and 40-50% with EMS). At a higher UV dose resulting in only 10% survival much longer expression times were required which cannot be explained by growth delays alone. While the reason for this is unknown it suggests that care must be taken in studies which require high mutagen doses. Representative revertants which were isolated show a range of phenotypes between those of tsH1 and WT. They appear to be a promising source of extragenic suppressor mutants [33] with alterations in functions affecting protein synthesis.


The fluctuation test as a more sensitive system for determining induced mutation in L5178Y mouse lymphoma cells. Luria-Delbrück fluctuation tests for the determination of the spontaneous mutation rate to ouabain resistance incultured L5178Y mouse lymphoma cells gave values in the range 0.44 to 1.03 X 10(-7) mutants per cell per generation. Addition of very low, non-toxic, levels of EMS (0.1 mM) and MMS (0.012 mM) 30-48 h before plating in selective medium gave a highly significant increase in the number of ouabain-resistant mutants. Methods for the calculation of spontaneous and induced mutation rates are discussed and a method for the computation of induced mutation rates is described. It is suggested that the modified fluctuation test is a simpler and considerably more sensitive assay for mutagens than the conventional experimental design. Some of its limitations are discussed.


[Effects of light on reproductive processes in fungi; hypotheses on the identity of photoreceptors. A bibliographic revue]. The present review describes the effects of light on reproductive processes in fungi, mainly when action spectra are available. The study of these has resulted in three kinds of photoresponses observable in fungi: - responses only to UV light (230-380 nm) - responses to NUV and blue light (300-520nm) - responses to great wavelengths of the visible spectrum. The photomorphogenetic processes on the control of these same photoreceptor pigments are reviewed.


Spontaneous mutation by mutagenic repair of spontaneous lesions in DNA. Strains of yeast carrying mutations in many of the steps in pathways repairing radiation-induced damage to DNA have enhanced spontaneous mutation rates. Most strains isolated because they have enhanced spontaneous mutation carry mutations in DNA repair systems. This suggests that much spontaneous mutation arises by mutagenic repair of spontaneous lesions.


Effect of alternate-day steroids on renal transplant function. A controlled study. A randomized, controlled study of the effect of alternate-day prednisone therapy on renal transplant recipients was done on 53 patients followed for 610 patient months. There was no difference between the 17 recipients of related donor organs who received alternate-day prednisone (experimentals) and their 15 controls who received daily prednisone nor between the 11 experimental and 10 control recipients of cadaver donor organs as regards: rejections per patient month, change in serum creatinine, doses of azathioprine or prednisone, or weight. Likewise the controls and experimentals of the related and cadaver groups did not seem different in either their blood pressure change or their tendency to lose their Cushingoid facies. Alternate-day steroids had no obvious effect on the development of posterior subcapsular cataracts in either related or cadaver organ recipients.


Response to parenteral iron with and without androgen therapy in patients undergoing regular haemodialysis. The effects of intravenous iron, with and without androgens, was studied in a group of 39 patients treated by regular haemodialysis, almost all of whom had normal serum iron concentrations. Intravenous iron 1-2 g every 4 months produced a significant rise in haemoglobin from 6.3 to 7.9 g/dl in 17 female patients with their kidneys in situ (p less than 0.001). In a group of 13 male subjects intravenous iron plus testosterone produced a similar rise in haemoglobin from 6.9 to 8.6 g/dl (p less than 0.001). Nine nephrectomised patients showed no significant response to iron and androgens. There were no fatalities and no serious side effects in 500 courses of intravenous iron.


Studies on erythropoiesis in patients with renal failure and after kidney transplantation. Ferrokinetic studies were made in 16 patients before and after kidney transplantation. The Fe clearance decreased in 9 of 11 patients, the plasma iron turnover showed no variation in six patients, while it increased in three and decreased in one, the production of hemoglobin increased significantly after transplantation. The nonnephrectomized patients showed more erythropoiesis after transplantation, manifested by higher hemoglobin level, shorter Fe clearance, and lower serum iron. Uremic patients, including the anephric, had significant responses in erythropoiesis both to stimulation by phlebotomy and to inhibition by blood transfusion. After transplantation, however, the response to phlebotomy was greater and the blockade by blood transfusion smaller, than during uremia.


Renal acidification in patients with mineralocorticoid deficiency. Renal acidification was studied in eight patients with Addison's disease or bilateral adrenalectomy receiving glucocorticoid replacement only and without renal insufficiency (group I); in five patients with hyporeninemic hypoaldosteronism and moderate chronic renal insufficiency (group II), and in nine control subjects (group III). During acidosis minimal urine pH was 5.4 or less in all subjects, but excretion of ammonium and titratable acid was moderately reduced in group I and markedly reduced in group II. Bicarbonate excretion at normal serum bicarbonate concentration was trivial in group I subjects and inappropriately elevated in two group II patients.


[Limits and prospects of gamma angioencephalography]. Among the informations that can be obtained from the gamma-angioencephalography, the two major aspects are limiting high resolution diagnosis:--on one hand, unspecificity of radio-active molecules for the different lesions,--on the other hand, insufficiency of detection possibilities and scintigraphy enhancement. On this last field fast sequential acquistions technics, data's filtering functional imaging bring much better inflamations. Recently, the new detectors with a high resolution power allow these technics to give to the physicians functional datas that can not be obtained with cumputerized tomography.


[Gamma cysternographic data in hydrocephalus and post-traumatic lesions]. With pneumoencephalography and pressure perfusions tests, the gamma-cisternography is a method of choice for establishing a reliable diagnosis of Normal Pressure Hydrocephalus (NPH) which concept was introduced by HAKIM. The gammacisternography allows to establish the diagnosis of NPH when a persistent ventricular filling is present and to find, very often, the etiological factor by showing the absence of radioactivity over the subarachnoïd pathways along the convexities at any stage or delayed and abnormal CSF absorption. The gammacisternography permits also to explore with 111 In DTPA the high risk patients who develop gradually over the course of months and years a NPH after a head trauma, a meningitis, a subarachnoïd hemorrhage or a neuro-surgery treatment. The NPH is present only 12 to 15% of our dementia cases with gait disturbance. Nevertheless, the search for such cases remains worthwhile as the patient may be able to return to a useful life after shunting procedure. The indication for shunting is not possible ot assess on scintigraphic results alone. It must be kept in mind that the abnormalities of CSF flow may be transient, may progress or regress. The shunting may be decided if the scintigraphic pattern remains unchanged and if the clinical symptoms are going worse. The pronostic is better in statistics after ventricular shunting when the NPH scintigraphic pattern is present. The valvo-scintigraphy can also evaluate the function of a shunt during the post-operative period.


[Diagnosis of cerebrospinal fluid leakages by gamma-cisternography]. Cerebrospinal fluid (CSF) leakages either secondary (traumatic) or spontaneous (non-traumatic) are first considered in their frequency and origin. The exact topography of the various meningeal and cranial lesions involved are difficult to assess particularly in the most important groups of persistant traumatic CSF rhinorrhea and recurrent meningitis. Among the various diagnostic approaches, direct observation is always necessary, but of limited value. Standard X-rays must be followed by multidirectionnal tomography (Polytome) and, whenever available, computed tomodensitography of the base of the skull. Brain pneumography provides a thorough setting fourth of the congenital or acquired cerebral lesions as well as the new cranio-meningeal conditions. Difficulties encountered with the techniques of subdurography and Pantopaque injection are underlined. Three radioisotope techniques are considered. 1) The earlier technique of cotton-pledgets only shows the external orifice. 2) The recent proposal of nuclide cranial subdurography is criticized for ignoring the leptomeningeal bag. 3) Radioisotope cisternography (RIC) or gamma-cisternography is described more precisely. It remains the most complete and appropriate method for observing the natural behaviour of the leakage. RIC with fistulography is performed through suboccipital injection of 99mTc-DTPA. RIC provides essential clues on the relative importance of associated dynamic disturbances of the third circulation and morphological changes of its anatomical bed (stenoses and widenings of the ependymal and leptomeningeal spaces). If present, the leakage may be directly shown on the RIC pictures. If rhinorrhea is abundant, there is no difficulty in assessing side and site of the fistula. If rhinorrhea is occult, dubious or intermittent, diagnosis is often difficult. There are also indirect signs of rhinorrhea: leptomeningeal dilatation near a frontal or ethmoidal fracture, contamination of the rhinopharynx, examination of the handkerchieves for presence of radioactive material. Statistical results from the literature are summarized in a table.


[Radioisotopic methods for studying cerebrospinal fluid shunts]. The article presents a general and critical review of the radio-isotopic methods for assessing the function of the surgical shunts of cerebrospinal fluid (CSF). The radio-isotope cisternography may indirectly demonstrate the function of the shunt by the postoperative modification of the eventual ventricular reflux and of the permeability of the subarachnoid spaces on the cerebral convexity. The methods of direct ventricular injection of the indicator permit a more direct assessment of the drainage, as based on a scintigraphy, or on the quantitative study of the cephalic radio-activity, or on the demonstration of radio-activityon a target-organ. The direct injection of a highly diffusible indicator in the valve allows a quantitative measurement of the flow of CSF in the shunt and brings morphological arguments for the localization of the eventual occlusion. The technical aspects of the latter method are critically discussed and illustrated by personal results.


[Comparative experimental study of microsurgical nerve suture. I. Immediate suture and delayed suture]. Impressed by multiplicity of theories and conceptions concerning nerve surgery and by the difficulty to draw grouded conclusions from the different and contradictory work available from the litterature on the subject, the author makes a revision of the biology of the nerve, to be used as a point of departure for investigation. Based on the fact that protheosynthesis capacity of the nerve cell is known to be at its top value during the first week after the lesion of the nerve, the author endeavours to compare immediate suture with delayed suture. This comparative study is based both on electrophysiological and histological data and show clearly enough the real advantage of trying nerve reconstruction as early as possible, to avoid progression of devitalisation and invasion by fibrosis of both stumps. The surgical procedures are made with the help of the operating microscope and the same technique is used in both groups.


Synthesis of LH-RH by rat hypothalamic tissue in vitro: I. Use of a specific antibody to LH-RH for immunoprecipitation. Following the procedure of Jeffcoate et al. [1974] we have successfully obtained a specific antiserum to LH-RH in rabbits, and are utilizing our antibody to study the synthesis of LH-RH by rat hypothalamic tissues in vitro. Our antibody, used at a dilution of 1:20,000, binds 37% of added 125I-labelled LH-RH, and cross-reacts minimally with thyrotropin releasing factor (TRF; 4.0%), somatotropin release inhibiting factor (SRIF; 0.035%), and melanocyte inhibiting factor (MIF; 0.009%). The antiserum recovers LH-RH added to charcoal-stripped rat serum quantitatively. Serial dilutions of rat hypothalamic extract and varying aliquots of normal rat serum are parallel to the standard curve (synthetic LH-RH: 0-100 pg/tube). Hypothalamic tissue of 4 male rats, bounded by the optic chiasm, mammillary bodies and hypothalamic fissures to a depth of 2-3 mm, was pooled, minced and incubated for 1-3 h in 2 ml of Eagle's Minimum Essential Medium in atmosphere of 95% O2/5% CO2 with 10 muCi of 3H-glycine. Reactions were stopped by the addition of 1 ml 0.1 N HC1. The tissue and medium were homogenized together and boiled for 3 min. Aliquots from the incubates were neutralized, LH-RH levels measured by radioimmunoassay (RIA), and 3H-glycine incorporation determined by immunoprecipitation, using our antibody. 3H-glycine incorporation into presumptive LH-RH increased linearly over the 3 h period. Aliquots of the 3 h incubates were chromatographed on Sephadex G-25 columns (1 x 10 cm) using 0.01 M acetic acid for elution; 1 ml fractions were collected. Synthetic LH-RH was chromatographed in a similar manner, and its elution profile determined by UV absorbance at 280 mm. Aliquots of each fraction of the eluted material from the 3 h incubates were counted in a scintillation counter to determine the elution pattern of the labelled material. Additionally, aliquots from the 1 ml fractions were neutralized and used for immunoprecipitation. Coincident peaks of 3H-label, immunoprecipitable 3H-labelled presumptive LH-RH, and synthetic LH-RH were observed. These results lend strong evidence to support our conclusion that the technique of immunoprecipitation is an efficacious approach to the study of the synthesis of LH-RH by rat hypothalamic tissue in vitro.


Biphasic effect of estradiol on mechanisms regulating LH release in ovariectomized sheep. Single injections of 50 mug estradiol-17beta (E2beta) into overiectomized sheep caused biphasic changes in plasma luteinizing hormone (LH). An initial 8-h period of LH inhibition was followed by a period (12-20 h after E2beta) of facilitated LH release. Pituitary LH responsiveness to small dosages of synthetic gonadotropin-releasing hormone (GnRH) was tested repeatedly at 2-h intervals during the time periods when plasma LH was inhibited and when it was facilitated. Reduced sensitivity to GnRH (91% decrease) characterized only the initial 4 h of the inhibitory period, suggesting that E2beta suppressed endogenous LH-releasing factor (LRF) during the latter part of the inhibitory period. Hypersensitivity (2-fold increase) to GnRH was briefly observed at the beginning of the period of E2beta-facilitated LH release. This transient and modest hypersensitivity does not completely account for the very large E2beta-induced increases in plasma LH. Therefore, E2beta probably increased endogenous LRF during the period of facilitated LH release.


Effect of testosterone on hypothalamic LH-RH content. Hypothalamic LH-RH content in male rats is lowered after castration. The s.c. implantation of testosterone or testosterone propionate-packed Silastic tubing (from 0.5 to 6 cm in length) in a range which encompassed the normal circulating plasma testosterone concentration, prevented this lowered LH-RH content 21 days following castration and simultaneous implantation. The temporal response to implanted testosterone was then studied: rats were killed 1,2,4,8,14 and 21 days after castration and simultaneous implantation of 3 cm testosterone-packed Silastic tubing. The hypothalamic LH-RH content began to decrease in the castrated group after 4 days and fell progressively thereafter. However, the hypothalamic LH-RH content of the castrated group maintained with constant levels of testosterone showed no such reduction at any time following castration. These experiments indicate that circulating testosterone in physiological concentrations can maintain a normal hypothalamic LH-RH content and demonstrate an action of testosterone, in physiological concentrations, in the feedback regulation of LH-RH secretion.


Alpha-methyldopa-chlorpromazine combination in schizophrenic patients. In a double-blind, controlled clinical study, lasting 8 weeks, 55 hospitalized schizophrenic patients were randomly assigned to one of the five drug treatments: 600 mg chlorpromazine/day, 300 mg chlorpromazine/day, 300 mg chlorpromazine--250 mg alpha-methyldopa/day, 300 mg chlorpromazine--500 mg alpha-methyldopa/day, 300 mg chlorpromazine--750 mg alpha-methyldopa/day. The results showed that all five treatments were significantly effective in treating schizophrenic behavior. The dose-response relationship for the different doses of alpha-methyldopa in combination with chlorpromazine, suggested an optimal response to 300 mg chlorpromazine--500 mg alpha-methyldopa.


Neuropsychobiology of affective disorders. Some methodological considerations. Amine hypothesis is neither an adequate nor a sufficient postulate in understanding the neuropsychobiology of affective disorders. Interactions and balance between various mechanisms and factors may be important. Better techniques and methodology need to be used and a more comprehensive approach seems to be necessary in formulating meaningful research strategies. The present paper reexamines someaspects of the available data and suggests a few approaches in the sutdy and elucidation of neruophychobiology of affective disorders.


[The free autologous dermo-adipose graft in the treatment of postoperative laparocele]. An account of the biological and contentive features of the derma is followed by a proposal for its utilisation in the form of an autologous, free dermo-adipose graft in the management of some forms of post-operative laparocele. Personal experience and technique are explained. Grafts are used both for reinforcement of the wall after simple laparoplasty and in the replacement of missing muscle-aponeurotic planes.


The spread of blood-borne metastases in malignant lymphomas of man. An autopsy study was performed on 190 cases with Hodgkin's disease and on 134 cases with reticulum cell sarcomas. It was found that a cascade spread of metastases, as opposed to a random spread, was detectable in patients with Hodgkin's disease, but not in patients with reticulum cell sarcoma. Metastatic key-sites for both lymphomas are defined as those organs whose chance of being seeded by the primary tumor is the highest; these sites are the spleen, liver, bone marrow and lungs. This study could not demonstrate in Hodgkin's cases that metastases in the liver and bone marrow were spleen dependent, but rather it showed that the spleen, liver and bone marrow acted as three independent sources of generalized metastases. Explanations proposed to account for the different metastatic spread in Hodgkin's disease and reticulum cell sarcomas, included different intrinsic cellular characteristics of the two lymphomas. the different location of the primary tumor either because of nodal, or of extra nodal origin, or because the primary tumor was located either in the upper or in the lower torso or in both areas. Malignant cells in the kidney, central nervous system and endocrine system were either released by the spleen via the lungs, or released by the liver and the lungs, or they were bone marrow dependent. The cascade spread of metastases hold true only for Hodgkin's disease. In cases with reticulum cell sarcomas, metastases appeared to spread at random from the primary tumor throughout the body, with rare exceptions such as metastases in the central nervous system, which originated either in the liver or in the spleen, lungs, kidney and bones.


Inhibition by ionophore A23187 of the cytotoxicity of vincristine, colchicine and X-rays to leukemic lymphocytes. The ionophore A23187 was tested for its effect on the sensitivity of normal and leukemic lymphocytes to colchicine, vincristine, and X-irradiation. The ionophore was used because it transfers divalent cations through biological membranes and causes the transformation of normal lymphocytes. The sensitivity of the cells was measured by incubation of lymphocyte suspensions with and without reagent at 37 degrees C for one to seven days and counting the number of viable lymphocytes before and after incubation. Viability of the cells was judged by cytologic criteria as visualized by phase contrast microscopy. Lymphocytes were obtained from patients with chronic lymphocytic leukemia and from normal persons. Colchicine and vincristine killed in one day non-dividing leukemic lymphocytes while normal lymphocytes were much less sensitive to the two alkaloids. X-irradiation (1000 rad) killed nearly all leukemic lymphocytes in two days and normal lymphocytes in three days. Ionophore A23187 (2 X 10(-5)M) was moderately toxic to normal but not to leukemic lymphocytes and caused the transformation of both types of cells. The ionophore inhibited the cytocidal action of colchicine and vincristine to leukemic but not to normal lymphocytes and inhibited the action of X-irradiation to both types of lymphocytes. The present findings and a review of the literature suggest the hypothesis that calcium or other divalent ions are involved in the cytotoxicity of colchicine, vincristine, and X-irradiation of leukemic lymphocytes and that there may be an abnormality of the metabolism of divalent ions in leukemic lymphocytes.


Antibody response to and immunity induced by Corynebacterium pyogenes vaccine. A procedure is described for producing a high quality C. pyogenes vaccine. A satisfactory antibody response was obtained by administering 3 subcutaneous injections of vaccine at 10-day intervals, using doses of 2,0 ml for rabbits, 5,0 ml for sheep and 10,0 ml for cattle. The titres resulting from this procedure compared favourably with those obtained from following the more intensive schedule and higher doses of vaccine recommended by the British Veterinary Codex. The antibody response was at its best 1-2 months after immunization but dropped to a plateau 6 months after immunization. Mice were also successfully immunized against challenge with 1,5x108 organisms by the application of 3 doses of vaccine administered at 10-day intervals.


[Research on hepatic and overall collagen metabolism in irradiated rats (author's transl)]. The authors studied the effect of ionising radiation on hepatic and overall collagen metabolism in rats. Doses of 100 and 250 rads produced a reduction in urinary hydroxyproline while doses of 500 and 700 rads produced an increase. These results may be interpreted in favour of an increase in reticulation in the first case and in the second case, destruction of inter-molecular bonds. The quantity of total and insoluble collagen increases proportionally to the dose 40 days after the radiation. This proportional relationship is not observed during the first few days after radiation. Prolonged radiation with 700 rads produces a marked reduction in all collagen fractions, compared with 4 days after acute radiation. Among the substances studied, "folcisteine" had the best radio-protective effect when administered before radiation with 700 rads.


[Immunoglobulins in the CSF during meningitis (author's transl)]. Cerebrospinal fluid and serum immunoglobulins were studied in 76 patients with acute meningitis of various aetiologies. This comparative study showed that the increase of CSF immunoglobulin levels was related to important modifications of the permeability of the blood-brain barrier (especially in case of bacterial meningitis) or to a local in situ production (particularly in case of "viral" meningitis). Results obtained allow us to draw a different biochemical pattern in purulent meningitis and acute lymphocytic meningitis.


[Practical interest of a micromethod for neuraminidase treatment of lymphocytes in transplantation immunology (author's transl)]. Vibrio cholerae neuraminidase treatment increases the cell sensitivity to complement and antibodies cytotoxic action. This property can be applied to the microlymphocytotoxicity technic for antibodies study in dialysed and kidney transplanted patients and for pretransplantation cross-matches. The enzymatic treatment usually employed needs a great deal of lymphocytes submitted in a second step to antibodies cytotoxic action. But this method appeared difficult to be routinely applied. We developed a simpler method consisting in treating only the lymphocytes needed to perform the test, on the reaction plate itself. This method gives the same results as the classical enzymatic treatment: the intensity of the weakly positive reaction is strongly increased, after pretreatment of cells; in certain cases, it allows one to detect cytotoxic antibodies not revealed without neuraminidase. These antibodies can be related (or not) to HLA system but practically the more important fact is the ability of this method to reveal an eventual incompatibility.


[Effect of clofibrate on tissue lipase activity in rats]. Given for 20 days at a concentration of 0.3% in the diet, clofibrate lowers serum triglyceride level and causes a 48% increase of lipoprotein lipase activity in rat fat pad, after feeding. This increase does not appear in the animals on fasting. These results agree with an effect of clofibrate upon membranous adenyl-cyclase of adipose tissue.


[Antibody coated bacteria in urinary sediment (author's transl)]. The presence of antibody coated bacteria in the urinary sediment was correlated with the infection site in 151 patients. 86 patients were followed regularly and support sequential data. A positive test is noted in most of the chronic pyelonephritis cases in all the prostatitis cases and in some of the chronic infection on bladder disease. In recurrent cystitis the test is generally negative as in acute pyelonephritis seen within 24 hours.


[Bone marrow's histopathology in tuberculosis of the hematopoietic organs (author's transl)]. Through the reports of the literature, the histopathologic lesions of the bone marrow in tuberculosis of the hematopoietic organs are analysed. Whether the lesions are typical or not, it is necessary to have a bacteriologic proof of tuberculosis. Near these lesions, bone marrow's cellularity is often greater or lower, reticular fibers are often increased and sometimes reticulin fibrosis is marked. Other necrosis and granulomatous inflammation are discussed. Contribution of macrophage is described. The relationships between tuberculosis and hematologic diseases are reported.


Tolerance and leukaemogenesis.

Tolerance and leukaemogenesis. Two subjects are considered here separately. Both are related to findings in the early embryo aggregation derived mouse chimaera model. Such chimaeras are most commonly derived following the aggregation of two undifferentiated embryos and therefore not suprisingly they were originally considered examples of "classic" immunological tolerance. Since this time alternative mechanisms including humoral and cell suppressor activity have been suggested and until recently tolerance in tetraparental chimaeras has remained a controversy. This controversy is now reviewed in the light of recent findings which has suggested that such mice are in fact examples of classic tolerance with the possibility that this is achieved by heterogeneous elimination of the clone of potentially self in equilibrium self auto-reactive cells. Chimaeras have also been studied in respect of leukaemogenesis. Results in a group of AKR reversible CBA leukaemia susceptible reversible resistant chimaeras suggest resistance is dominant. Moreover evidence now points to lack of anti-viral antibody activity in these chimaeras which I wish to suggest may be related to apparent resistance to leukaemia. In this context it may be envisaged that in the absence of masking anti-viral antigen complexes "normal" tumour immunity may have been effected. Although this has yet to be proven evidence points to tolerance to the oncogenic virus being maintained in the chimaeras furthermore also in the naturally derived (AKR X CBA) F1. This in turn leads me to suggest that "intolerance" to the oncogenic virus, the spontaneous development of anti-viral antibodies and tumour development might well be related in the AKR. This in turn enables me to propose that tolerance and leukaemogenesis, at least in this stiuation, appear to be related.


[Bidimensional electrophoresis in the study of cerebrospinal fluid protein (author's transl)]. The authors report 650 bidimensional electrophoreses of the cerebrospinal fluid (CSF). All examinations were carried out after prior concentration of CSF protein. The technic used is that described by Rebeyrotte in 1970. Four types of tracing were noted: -- Two tracings were unusual by the presence of a large peak in the alpha-2 region. -- One tracing was of the hypergamma type. -- One tracing was comparable to serum by the richness of the precipitations. A change in the first migration permitted us to obtain electrophoretic separations from 100 microlitres of pure CSF. The bidimensional immunoelectrophoresis tracings are comparable to those described previously.


[Effect of phosphate upon calcium intestinal absorption (author's transl)]. Adult rats receive 5 to 50 mM CaCl2 solutions in which glycerophosphate or sodium diacid phosphate may be added in variable quantity. These solutions are administered by gavage or in situ ligatured jejunal loop. The inhibition of calcium absorption dependent on simultaneously administered phosphate doses is well characterized: high for the lowest concentration, the inhibiting effect of phosphate doses decreases more and more reaching a limit from which phosphate supplementation has no effect. These observations discarding an intervention of phosphate by calcium insolubilization seem to demonstrate that the control supplied by phosphates on calcium absorption is of enzymatic character. Facts related to the respective effects of calcium and phosphates on the action of alkaline phosphatases lead to discuss a possible intervention of these enzymes upon calcium transfer.


[Bronchial lympho-epithelial nodules in the rat. Definition and morphological characteristics in optical and electron microscopy (author's transl)]. Among the bronchial lymphoid tissue, lympho-epithelial nodules are an original component, easily distinguished from other structures, particularly from lymphoid cell infiltrates. Such structures are encountered in many species and may be characterized by a flattened epithelium, containing a few ciliated cells, devoid of mucus producing cells, and infiltrated with lymphocytes. Inter and intracellular vacuoles are described in the lympho-epithelium and the underlying mucosa. Electron microscope studies support the view that lymphoepithelium has a "trapping" function of particulate matter, more direct evidence is however attempted. Peripheral lymphatic vessels and high endothelium veins contribute to the important lymphocyte transfer. An hypothesis of capacity for antigenic recognition of the lymphoepithelial nodule is discussed.


Antigenic analysis of a variant specific component of Trypanosoma Brucei Brucei I -- Immunochemical purification by affinity chromatography. An antigenic component specific to the bloodstream form of serotype AnTat-1 of Trypanosoma brucei brucei was purified by immunoadsorption technique. Subsequently, a monospecific rabbit antiserum was prepared. Purity and specificity controls of the final product were carried out by immunoelectrophoretic analysis.


Histological aspects of arterial abnormalities produced by X-irradiation of the aortic and branchial arches in the chick embryo. Low dose X irradiations centred on one or two aortic and branchial arches of 3-day check embryos result in teratogenic effects on the arteries (21-92%) and in low mortality (4-12%). Histological studies of abnormal arteries show different structural malformations of the arterial wall: inorganized arterial fibres, abnormal intima, newly formed arterial tissue in arterial lumen, coalescence of two arteries. It is suggested that a disturbance at the aortic differentiation level results under our experimental conditions in the observed arterial abnormalities.


[Bactericidal power of polymorphonuclear neutrophils. Trials for standardization of a micromethod using autoradiography (author's transl)]. A 50 mul sample of blood is placed successively in the presence of staphylococci, then of tritiated thymidine. Stripping film autoradiography permits identification of living intracellular bacteria which metabolize the marked precursor. In our experimental conditions, the percentage of marked intracellular bacteria is: -- 15,4 +/- 3,7% (x +/- 1s) among adults -- 14,6 +/- 3,2% among children.


Human platelet fibrinogen: a protein different from plasma fibrinogen. Fibrinogen has been purified from normal and dysfibrinogenemia Metz plasmas, and from normal and from the patient's platelets. There are differences in the pattern of disc polyacrylamide gel electrophoresis between normal plasma and normal platelet fibrinogens, but the migration of the A alpha chain is similar. The abnormality of the electrophoretic mobility of the A alpha chain of plasma fibrinogen from Metz dysfibrinogenemia is not found in platelet fibrinogen of this patient. This result clearly establishes that platelet fibrinogen is a different protein from plasma fibrinogen.


[Vascular subendothehlium: structure and functions (author's transl)]. Two subendothelial structures, glomerular basement membrane and arterial subendothelium, were compared regarding their biochemistry and ultrastructure and their role in physiology and pathology. Filtration function of the glomerular basement membrane can be related to the presence of three layers which are superimposed on each other and which differ regarding the orientation  and density of the microfibrils. The arterial subendothelium which is a mixture of amorphous material, microfibrilis, elastin and collagen, with a still unknown orientation of these components, limits the transport of many blood molecules and reinforces the endothelial barrier. A striking difference is observed in the thrombogenicity of these two structures, especially in their reactivity towards platelets. This can be related to the presence of collagen IV in the glomerular basement membrane and of collagen III in the arterial subendothelium: in both cases adhesion of platelets can be observed. The presence of platelet aggregates on the subendothelial surface may also be seen. This is probably due to the presence of collagen III which is known to be able to induce the platelet release reaction and thereby promotes aggregation.


Inhibition of platelet aggregation by cationic protein from polymorphonuclear leukocytes. The cationic protein isolated from the granules of neutrophilic polymorphonuclear leukocytes inhibited the aggregation of human platelets as induced by collagen, thrombin, ristocetin, aggregated IgG by approximately 50% and anti-C1q by 75% but had no effect on aggregation-induced by ADP.


Galactosyl transferase assay. Application to experimental atherosclerosis. To establish a repetitive measurement, aortic galactosyl transferase activity has been studied with a specific exogenous acceptor, collagen. Reactions were realized with an acellular biosynthesis mixture containing, collagen (3-4 mg/ml) an aliquot of enzymatic extract preparation (105000 g supernatant (2-3 mg/ml of proteins), UDP (14C) galactose (300 pM/ml). Galactose incorporation into collagen required Mn++ (2.5. 10-3M), incubation temperature of 37 degrees C and pH =7,75. Under such conditions a reproducible assay of aortic collagen galactosyl transferase was possible. After submitting rabbits to a chronic lathyric intoxication and/or to an hypercholesterolimic diet, galactosyl transferase activity was measured in rabbit aortic wall. Enzymatic activity was increased for rabbits under treatment, and the increase was directly proportional to the length of treatment (BAPN associated with cholesterolemic diet).


Biosynthesis of elastin and other matrix-macromolecules in veinous arterial prosthesis. Homologous saphenous veins where implanted in the arterial circilation (femoral artery) of dogs for various times (1 to 9 months, most data given for 3 months). After this period, the in vitro biosynthesis of intercullar matrix macromolecules was studied by incubating the veins in organ culture conditions in the presence of 14C-lysine for 3 days. A fractional extraction procedure was used to obtain representative macromolecular extracts for the determination of chemical composition (hydroxyproline, hexosamines) and radioactivity. Neosynthesis of elastin was considered as valid criteria for the adaptation of the veinous wall to the new (arterial circulatory) conditions. The chemical composition of the grafted veins was different from that of the nongrafted, controlateral saphenous veins suggesting a molecular remodeling of the grafted veinous wall. Radioactive lysine was incorporated in all macromolecular fractions of grafted and control veins. The specific radioactivity of the extracts obtained from grafted veins was higher than that obtained from the control veins. The only exception was the collagenase extract (containing mainly the polymeric collagen) which had a somewhat lower radioactivity in the grafted vein. The incorporation of lysine in the elastin fraction increased by a factor 10 in the grafted vein as compared to the non-grafted veins. Radioactive desmosine could be demonstrated in the elastin fraction. It appears therefore that the veinous wall could adapt its biosynthetic capacity to the new circulatory conditions by increasing considerably the biosynthesis of elastin. This is accompanied by an increase of the synthesis of other macromolecules and a significant remodeling of the macromolecular structure of the vessel wall.


[Von Willebrand factor activity and thrombophilic states. A review (author's transl)]. After a brief survey of some physiologic properties of Von Willebrand factor activity (VIII r WF) the numerous clinical states with an increase of this activity are described. The authors report their own results concerning sepsis, chronic arteritis of lower limbs, diabetes, toxemia of pregnancy. In most cases the increase of VIII r WF activity appears as a sign of vascular injury and/or the consequence of tissular damage.


Factor V and VIII activation "in vivo" during bleeding. Evidence of thrombin formation at the early stage of hemostasis. Factor V and VIII activity was measured by a one-stage assay on capillary blood issuing from a skin cut. This activity increases during bleeding. The phenomenon is suppressed by a previous injection of a low dose of heparin. These data give evidence of a very early local formation of thrombin during hemostasis. The study of this activation process in patients with congenital deficiency of blood clotting factor allows to investigate the mechanism of thrombin formation in vivo. This demonstrates the preeminence of the tissue factor pathway and the need of factor VIII for factor X activation in the extrinsic system.


Two simple methods for the quantitative evaluation of platelet adhesion to collagen. 14C serotonine labelled platetel rich plasma (PRP) incubated with fibrillar collagen is either gel filtered through a Sepharose 2B column (Sepharose test) or centrifugated on a 23% Ficoll layer (Ficoll test). In the Sepharose test, the adhesion is quantified by the determination of the per cent yield of free platelets eluted from the column and the release by a quantitative evaluation of the 14C serotonin. In the Ficoll test, the released seroton is measured from the distribution of radioactivity in the different layers (supernatant plasma, platelets adherent to collagen, Ficoll, platelet pellet) of the tube after centrifugation. Both methods are rapid and quite reproducible.


Semantic memory: a bibliography, 1968-1975. Semantic memory research is briefly described. Then a bibliography of 105 published references in semantic memory, calendar years, 1968-1975, is presented.


Personality and meditation.

Personality and meditation. The relationship of psychoticism, extraversion-introversion, and neuroticism to the practice of Transcendental Meditation was studied. Male meditators (n = 39) were more introverted and more neurotic than the normal population, whereas the female meditators (n = 27) had a higher mean psychoticism score. Over a 6-mo. period of meditation, the males (n = 24) became less neurotic; the degree to which they did so was related to the frequency of meditation. The implications of these findings are discussed.


Relationship between spatial density and sensory overload, personal space, and systolic and diastolic blood pressure. Selected effects of high spatial density were investigated with 26 boys, serving as their own controls and undergoing alternate confinements in high and relatively low spatial density. Measured effects were changes in minimal aversion threshold values of white sound, projective measures of desire to alter room size, and systolic and diastolic blood pressure. High spatial density increased systolic and diastolic blood pressure and projective measures of desire to alter room size but did not affect minimal aversion threshold values. Semi-projective measures of personal space requirements were obtained prior to experimental trials. Analysis showed a significant interaction of minimal aversion threshold values with requirements for personal space; the minimal aversion threshold values of subjects requiring large personal space tended to decrease following confinement under high spatial density. The interaction of personal space with projected measures of desire to alter room size was not significant. High spatial density may, then, exert adverse effects on blood pressure and may induce sensory overload conditions in individuals requiring large personal space.


[Isolation and function of platelets. I. Platelet rich plasma. Comparison between 2 methods: gel filtration and albumin density gradient centrifugation. II. A new method using total blood: metrizamide gradient centrifugation]. Human platelets separated from platelet rich plasma (PRP) by two different methods: gel filtraton and centrifugation on albumin gradient have been compared for yield, cellular and protein contamination, ultra-structure, platelet populations, shape change, aggregability and functional preservation. A new method for the separation of platelets from total blood on metrizamide gradients has been established. This technique is rapid and easy; it avoids the initial centrifugation of the PRP where about 30% of the platelets are lost and needs of blood 5 to 10 ml of blood.


Studies on antilipolytic activity of antipyretics. Part I. Influence of sodium salicylate, acetylsalicylic acid, phenazone, aminophenazone, and acetophenidin on lipolysis in fever induced by E. coli pyrogen. The fever induced by E. coli pyrogen (LPS) is accompanied by a rise of FFA and glycerol level. All tested antipyretics inhibited both thermogenesis of lipolysis produced by LPS. These results suggest that the antipyretic effect of antipyretic drugs is not confined to their action on heat-dissipating mechanisms, but may also be exerted by a depression of lipid metabolism.


Medical versus surgical treatment of stable angina pectoris: progress report of a large scale study. A large scale, prospective, randomized study of surgical v. medical management of disabling angina pectoris is being conducted as a cooperative study among thirteen Veterans Administration hospitals in the U.S.A. A total of 1015 patients have been entered into the study and follow-up data are currently being evaluated. Patient entry into the study was concluded in December 1974. Patient compliance has been acceptable with only 7% of patients not adhering to their randomization category. Thirty-day operative mortality (1972-1974) in 309 patients was 5-3%. The patient population exhibited a severe degree of coronary disease. There was ECG evidence of prior myocardial infarction in 40%. There were significant obstructive lesions in three major coronary arteries in 51% and significant lesions of the left main coronary artery in 11%. Medical and surgical treatment groups demonstrated no significant differences in objective descriptive characteristics. Mortality in the medical group at 1 year was 8%. Mortality was influenced by several factors including the number of vessels involved, left ventricular function and the presence of left main coronary artery disease. The lowest mortality occurred in patients with single vessel disease and normal LV function who had a 1-year mortality of 3%. Patients with 3-vessel disease and abnormal LV function exhibited a 14% 1-year mortality. Patients with disease of the left main coronary artery and poor LV function had a 1-year mortality of 37%. Analyses of the results of treatment modalities in sub-groups is currently being performed and will be reported in future publications.


Principal aspects of the use of placebos. After a brief historical review the author discusses the use of placebo in treatment and in the scientific evaluation of the efficacy of psychotropic drugs in double-blind studies. He also mentions its place in the elucidation of the personality structure and psychodynamics of so-called placebo reactors, as well as its importance in recent years for basic medical research.


[Pimozide in non-psychotic elderly patients with behavioural disturbances. An open study (author's transl)]. 20 non-psychotic aged (more than 60 years old) in-patients with behavior troubles were treated with pimozide in an open study for more than 12 weeks. Such symptoms deriving from the emotional sphere, mainly the aggressivity, had the best improvement rate. Together with this could also be seen an improvement of the social behavior. The dosage optimum was between 3 and 4 mg p.d., the improvement period seems to reach from the second to the eighth week. Extrapyramidal side-effects were rare, two patients developed, after more than nine months of therapy and long after the study had finished, a tardive hyperkinesia which was reversible after the withdrawal of the substance.


The Comorosan effect: single- and double-blind studies on the urea/urease system. Characteristic alterations of enzymatic reaction rates by irradiation of the crystalline substrates for fixed periods with an Hg vapor lamp were reported by Comorosan in 1969. Results of single- and double-blind studies reported here support the validity of the key features of this striking and potentially important phenomenon.


[Pharmacoangiography of the pancreas (author's transl)]. The value of pancreatic pharmacoangiography was assessed in 269 visceral angiograms comparing pre- and postpharmacoangiographic series. Angiotensin as a vasoconstrictor was studied in 179 patients, Adrenalin in 50 patients. Experiences with vasodilators based on 40 angiograms carried out with Secretin and Tolazolin were evaluated respectively. After application of Angiotensin, enhanced filling of small arteries in the head of the pancreas was achieved in 75% of patients. Good filling of small arteries of the body of the pancreas rose from 26 to 55%, while angiography with vasoconstrictors seems of low value in the tail of this organ (20% improvement). The diagnostic information of angiography was improved in 4 of 43 carcinomas (10%). Confirmation or exclusion of questionable pathologic alterations are a further, though not measurable advantage of this method. Pharmacoangiography with constrictors is recommended as an alternative method if superselective angiography is not possible. The use of vasodilators for better imaging of the pancreatic parenchyma is of no significant diagnostic value. The use of vasodilators for better presentation of the spleno- and mesenterico-portal axis is advisable because dilatation of the capillary system permits application of larger doses of contrast medium and a higher flowrate. This causes early and more intensive imaging of the veins.


Immunologic aspects of human sarcomas.

Immunologic aspects of human sarcomas. Forty-seven patients with mesenchymal sarcoma seen at the Mayo Clinic were tested for humoral and cellular immunologic responsiveness by means of a humoral cytotoxicity test, skin tests for delayed-type hypersensitivity, and lymphocyte transformation with concanavalin A, phytohemagglutinin, and pokeweed. Prospective follow-up of the clinical and laboratory results revealed that patients with low humoral cytotoxic indices, anergic skin test responses, or low lymphocyte transformation responsiveness tended to have the worst short-term clinical outlook.