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NUCLEAR fINE-STRUCTURE AT INTERPHASE AND DURING ENCYSTMENT IN 2 fORMS Of THE TESTACEAN ARCELLA-VULGARIS

EUROPEAN JOURNAL Of PROTISTOLOGY 1989年第4期24卷 369-380页

作者： RAIKOV, IB KARADZHAN, BP KAUR, R MIGNOT, JP UNIV CLERMONT FERRAND 2 ZOOL & PROTISTOL GRP COMPLEXE SCI CEZEAUX F-63177 AUBIERE FRANCE

Arcella vulgaris and A. vulgaris var. multinucleata have two and seven vesicular nuclei, respectively. In early interphase, the nuclei are spherical, with a main central nucleolus and several small peripheral nucleoli. The main nucleolus has mixed fibrillar and granular components and no apparent chromatin bodies in the nucleolus-organizing regions (NORs). The nuclear chromatin is dispersed except for all small heterochromatin lumps. Nuclear bodies of fibrous structure occur outside the main nucleolus. The nuclear envelope shows an internal lamina and an external layer of tangential fibres. In middle interphase, the nuclei become irregular in shape and adjacent to the plasma membrane at the dorsolateral cell surface. The condensation of the chromatin increases. The nucleolus is often eccentric and its NORs show conspicuous bodies of condensed chromatin surrounded by a halo and a fibrous transcription zone. By the end of interphase, the main nucleolus becomes polymorphic and segregated into a fibrillar basal part which contains a vacuolar area with dense inclusions, and a fibro-glanular cap which contains many fibrous electron dense bodies. These are likely to be the nuclear chromatin elements. In early resting cysts, the nuclei detach from the cell membrane and approach one another. The main nucleolus segregates into large, mainly perpheral fibrillar blocks inside a granular mass. The NORs consist of condensed chromatin bodies without a transcription zone around them. The nuclear chromatin is condensed. Conspicuous intranuclear annulate lamellae bearing pore complexes occur only in cysts.

关键词： AL annulate lamella AN additional nucleolus AV autophagic vacuole Ax axosome BP basal part of amphinucleolus C cap of amphinucleolus CH chromatin CM cell membrane CW cyst wall DB dense bodies (in nucleoli) f perinuclear fibrils fA fibrillar aggregates (in nucleoli) fB fibrous bodies (in nucleolar cap) fC fibrillar centre fI food inclusion L nuclear lamina M mitochondrion N nucleus NB nuclear body NC nucleolar chromatin NE nuclear envelope NL main nucleolus R ribosome mass S sphere T test TG thecagenic granules

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DIffERENTIAL INDUCTION Of SUCROSE METABOLIZING ENZYMES IN WHEAT (TRITICUM-AESTIVUM CV SANAGUSTIN) LEAf SECTIONS

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JOURNAL Of PLANT PHYSIOLOGY 1989年第2期134卷 214-217页

作者： SALERNO, GL IANIRO, JL TOGNETTI, JA CRESPI, MD PONTIS, HG UNIV NACL MAR DEL PLATA INST INVEST BIOL RA-7600 MAR PLATA ARGENTINA

The effect of carbohydrate supply on sucrose metabolism was studied in wheat leaf sections. Incubation with glucose, fructose or sucrose resulted in an increase of sucrose level followed by accumulation of fructans. Concomitantly, surcose phosphate synthase (SPS) activity increases continuously throughout the length of the experiment (48 hours) while sucrose synthase (SS) was unaffected for the first 30 hours. The de novo synthesis of SPS is suggested by Western blots and by inhibitiors of protein synthesis. The different temporal pattern sof SPS and SS activation indicate the distinct roles played by these enzymes in leaves.

关键词： Triticum aestivum fructans sucrose sucrose phosphate synthase sucrose synthase CHI cycloheximide DP degree of polymerization fS fructosyl sucrose f 2 S fructosyl fructosyl sucrose fW fresh weight SPS sucrose phosphate synthase SS sucrose synthase TBA thiobarbituric acid

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PROPERTIES Of fRUCTOSYLTRANSfERASES INVOLVED IN THE SYNTHESIS Of fRUCTAN IN LILIACEOUS PLANTS

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JOURNAL Of PLANT PHYSIOLOGY 1989年第2期134卷 151-155页

作者： SHIOMI, N Department of Food Science Faculty of Dairy Science Rakuno Gakuen University Ebetsu Hokkaido 069 Japan

We isolated nine fructo-oligosaccharides from asparagus roots and onion bulbs, and identified them aauthor f (1-ß-D-fructofüranosyl) n sucrose n = 1, 2 and 3, 6 G (1-ß-D-fructofüranosyl) n sucrose n = 1, 2 and 3 and l f (1-β-d-fructofüranosyl) m -6 G (1-ß-D-fructofüranosyl) n Sucrose m = 1, n = 1; m = 2, n = 1; and m = 1,n = 2. The nine fructo-oligosaccharides were synthesized in vitro from sucrose by enzyme preparations ofasparagus roots and onion bulbs. Three different types of fructosyltransferases are suggested to be involved in the synthesis of the saccharides. The fructosyltransferases were highly purified and their substrate specificities were investigated indetail. They were confirmed to be sucrose : sucrose 1 f -ß-D-fructosyltransferase (SST, EC 2.4.1.99), 1 f (1-ß-D-fructosyl) n sucrose : 1 f (1-β-d-fructosyl) m sucrose 6 G -ß-D-fructosyltransferase (6 G -fT) and 1f(1-ß-D-fructosyl) n sucrose: 1 f (1-ß-D-fructosyl) m sucrose 1 f -ß-D-fructosyltransferase (1 f -fT). from the properties and substrate specificities of SST, 6 G -fT and 1 f -fT, a scheme for the biosyntheticpathways of fructans in asparagus and onion plants was proposed.

关键词： fructosyltransferase fructo-oligosaccharide Asparagus officinalis L. Allium cepa L SST sucrose : sucrose 1 f -ß-D-fructosyltransferase 6 G -fT 1 f (1-ß-D-fructosyl) n sucrose : 1 f (1-ß-D-fructosyl) m sucrose 6 G -ß-D-fructosyltransferase 1 f -fT 1f(1-ß-D-fructosyl)nsucrose : 1 f (1-ß-D-fructosyl) ms sucrose 1 f -ß-D-fructosyltransferase

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DISSOCIATION KINETICS Of ANTIGEN-ANTIBODY INTERACTIONS - STUDIES ON A PANEL Of ANTI-ALBUMIN MONOCLONAL-ANTIBODIES

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MOLECULAR IMMUNOLOGY 1989年第2期26卷 129-136页

作者： OLSON, WC SPITZNAGEL, TM YARMUSH, ML RUTGERS STATE UNIV DEPT CHEM & BIOCHEM ENGN PISCATAWAY NJ 08854 USA MIT DEPT CHEM ENGN CAMBRIDGE MA 02139 USA

Kinetic parameters and equilibrium association constants (K) are reported for a panel of anti-bovine serum albumin (BSA) monoclonal antibodies (MAb) immobilized onto agarose particles. for 12 covalently immobilized MAb of moderate affinity (K = 0.25 .times. 108-1.2 .times. 108 M-1) measured dissociation time constants varied two orders of magnitude, from 2.1 to 410 min. Directly measured association rate parameters agree with values calculated from measured equilibrium and dissociation rate parameters. Dissociation time constants and equilibrium association constants were also determined for eight MAb immobilized biospecifically (via their fc regions). A significantly lower K was observed with those MAb which were covalently immobilized as opposed to biospecifically immobilized. These decreases in K appear to reflect decreased association rates rather than increased dissociation rates. The data suggest that, for the MAb described herein, dissociation rates do not correlate with equilibrium association constants.

关键词： c free Ag concn c0 initial Ag concn f fraction of Ag irreversibly bound K equilibrium association constant Kb equilibrium association constant of biospecifically immobilized MAb Kc equilibrium association constant of covalently immobilized MAb k1 second-order association rate constant n number of active binding sites per mole of MAb q bound Ag concn q0 initial concn of immobilized MAb t time θ fraction undissociated θ dissociation time constant (inverse of the first-order dissociation rate constant) θb dissociation time constant of biospecifically immobilized MAb θc dissociation time constant of covalently immobilized MAb

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EffECTS Of UV-RADIATION ON CELLS

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JOURNAL Of PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 1989年第1期4卷 21-34页

作者： MOAN, J PEAK, MJ ARGONNE NATL LAB DIV BIOL & MED RESMOLEC PHOTOBIOL GRPARGONNEIL 60439

UV radiation interacts with mammalian cells in a very complex manner, although DNA appears to be the main chromophore. Recent literature within this field is reviewed. The review is concentrated on the following main topics: Chromophores for UV action, photoproducts in DNA, repair of UV-induced DNA damage, wavelength interactions, inactivation, mutagenesis, transformation and protection mechanisms against UV damage.

关键词： UV light carcinogenesis mutation chromophores action spectra photoproducts in DNA DNA repair inactivation. UVA, radiation in the wavelength region 320–400 nm UVB, radiation in the wavelength region 290–320 nm UVC, radiation in the wavelength region below 290 nm CPD, cyclobutyl pyrimidine dimer (6-4) photoproduct, pyrimidine (6-4) pyrimidone photoproduct PRE, photoreactivation enzyme (photolyase) SSB, DNA single-strand break DBS, DNA double-strand break DPC, DNA-protein cross-link XP, xeroderma pigmentosum UDS, unscheduled DNA synthesis UCA, urocanic acid AA, arachidonic acid f 37 , fluence at which 37% of a given cell population survives.

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A THIN-LAYER MULTISTRIP AGAROSE-GEL ELECTROPHORESIS APPARATUS fOR fERGUSON PLOT ANALYSIS AT THE SUB-MICROGRAM LOAD LEVEL

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JOURNAL Of BIOCHEMICAL AND BIOPHYSICAL METHODS 1989年第1期19卷 105-120页

作者： ORBAN, L SULLIVAN, JV CHRAMBACH, A NICHHD MACROMOLEC ANAL SECT THEORET & PHYS BIOL LAB BLDG 10 RM 6C101 BETHESDA MD 20892 USA NIH DIV RES SERV BIOMED ENGN & INSTRUMENTAT BRANCH BETHESDA MD 20892 USA

A method for the simultaneous horizontal agarose gel electrophoresis on thin-layer strips of different gel concentrations was developed for the purpose of generating ferguson plots at the sub-microgram load level. Seven independent gel strips on a common GelBond support were formed by filling channels created by a comb-shaped spacer (polycarbonate) in a vertical multistrip cassette. Electrophoresis on a horizontal Peltier-cooled surface employed commercial apparatus (E-C Apparatus Corp.) with a modified cover which is airtight and holds anodic and cathodic voltage measurement probes for each strip. The application of the apparatus to ferguson plot analysis in a single experiment was exemplified on the RNA-containing turnip crinkle virus (TCV) at a load of 50 ng/gel strip, using an optimized silver staining method (a modification of a procedure of fMC Corp. BioProducts) for detection. Within the range of 3.5 to 12.5 V/cm, the plot was found to be independent of field strength. Mobility is also independent of the concentration of detergent (CHAPS) up to 10 mM.

关键词： Agarose Gel electrophoresis Thin-layer multistrip Multigel Silver staining Virus ACES N -(2-acetamido)-2-aminoethanesulfonic acid CHAPS 3-[(3-chlamidopropyl)-dimethyl ammonio]-1-propane sulfonate DTT dithiothreitol ferguson plot plot of log(mobility) or log(R f ) vs gel (agarose) concentration HEM N - β -hydroxyethylmorpholine K R retardation coefficient, slope of the ferguson plot MES N -morpholino]ethanesulfonic acid TCV turnip crinckle virus μ absolute mobility (10 −5 cm 2 ·s −1 ·V −1 ) μ 0 μ at % agarose = 0

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PRELIMINARY-STUDY Of THE INHERITANCE Of TEMPERATURE STRESS PROTEINS IN BARLEY (HORDEUM-VULGARE-L)

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PLANT SCIENCE 1989年第2期62卷 147-156页

作者： MARMIROLI, N LORENZONI, C STANCA, AM TERZI, V UNIV LECCE INST GENET DEPT BIOL I-73100 LECCE ITALY UNIV PIACENZA INST GENET I-29100 PIACENZA ITALY EXPTL INST CEREAL RES SECT FIORENZUOLA ARDA I-29017 FIORENZUOLA ARDA ITALY

Comparisons of three barley genotypes, two parentals and their f1 offspring, were made for protein synthesis modifications upon exposure to a wide range of temperatures from ***. to ***. C. The two parental genotypes were selected for their differences in growth habit, geographical origin, spike type and cold hardiness characteristics. Moreover the two genotypes differed in specific proteins which appeared at low or at high temperatures. The f1 progeny obtained showed the following characteristics: (a) some of the heat stress induced proteins (HSP) had similarity with those of the parentals;the highest number of similarities was found between f1 and the Georgie parental;(b) the pattern of HSP induced was different at ***. and ***. C, a temperature dependency which is typical of Onice at the level of coleoptiles and specific of Georgie at the level of roots;(c) a relevant number of HSP in f1 had no parental counterparts, i.e. they were f1 or hybrid specific. Analysis of the cold induced proteins (CSP) showed the f1 progeny inherited most of the CSP characteristics of both parentals, though with a preference of the Onice parental at least at the level of coleoptiles. These results, that few stress genes had an uniparental heredity, whereas other stress genes showed an f1 specific pattern of expression may probably be a consequence of new regulatory interactions which took place in the hybrid between the stress genes of the two parentals.

关键词： stress proteins f 1 hybrids barley

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TOPO-DYNAMIC CHARACTERISTICS Of HUMAN-PLASMA VLDL APOLIPOPROTEINS AND EffICIENCY Of TRIACYLGLYCEROL HYDROLYSIS BY LIPOPROTEIN-LIPASE

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BIOCHIMICA ET BIOPHYSICA ACTA 1989年第1期1005卷 79-86页

作者： DERGUNOV, AD SHUVAEV, VV PEROVA, NV MOSCOW PREVENT MED RES CTR DEPT BIOCHEM 10 PETROVERIGSKI ST MOSCOW 101953 USSR

A lower accessibility to water-soluble quenchers of tryptophanyls of VLDL apolipoproteins B, E, C, as compared to LDL apoB chromophores has been detected by a fluorescence quenching technique. The dynamic behavior of the tryptophanyls of VLDL amphipathic apolipoproteins E and C did not change in the presence of a detergent, Tween-20, at sub-lytic concentrations. However, a reversible structural transition registered by the ''red'' shift of the emission spectrum maximum and the changes in the quenching pattern by I- occurred under these conditions. The increase in the VLDL tryptophanyl accessibility to acrylamide and the decrease in the quenching constant were observed at partial and complete solubilization of the VLDL particles by the detergent. Dissociation of apolipoproteins from VLDL occurred after their treatment with Tween-20 or lipoprotein lipase isolated from bovine milk, and the tryptophanyl population not participating in fluorescence energy transfer on lipid phase-localized fluorescent probe pyrene appeared. In the presence of Tween-20, the relative affinity of apoE for the lipid matrix of VLDL was lower than that of apoC. Besides, the uncompetitive mode of inhibition of the LPL activity by apoC-III has been demonstrated. It is suggested that: (1) the amphipathic apolipoproteins E and C are organized as clusters on the VLDL surface and/or partially shielded by apolipoprotein B;(2) self-regulation of lypolysis may exist involving detergent-like reaction product accumulation and changes in relative apolipoprotein contents.

关键词： Lipid hydrolysis VLDL Apolipoprotein topography (Human plasma) VLDL very-low-density lipoproteins LDL low-density lipoproteins HDL high-density lipoproteins LPL lipoprotein lipase apoA B, E, C, apolipoproteins of VLDL (apo B, E and C) LDL (apoB) HDL (apoA, E and C) K SV Stern-Volmer quenching constant f chromophore accessibility for quencher molecules K m app apparent Michaelis constant V max app apparent maximal reaction velocity SDS sodium dodecyl sulfate

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SLOW fLUCTUATIONS Of SINGLE UNIT ACTIVITIES Of HIPPOCAMPAL AND THALAMIC NEURONS IN CATS .1. RELATION TO NATURAL SLEEP AND ALERT STATES

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BRAIN RESEARCH 1989年第1期487卷 26-34页

作者： KODAMA, T MUSHIAKE, H SHIMA, K NAKAHAMA, H YAMAMOTO, M TOHOKU UNIV SCH MED DEPT NEUROPHYSIOL SENDAI MIYAGI 980 JAPAN

Spontaneous unit discharges during the natural sleep-wakefulness cycle in two different neuronal groups, the hippocampal pyramidal cells and thalamic ventrobasal neurons, have been analyzed. The results show that both neurons fire with white-noise-like fluctuations during the slow-wave sleep, and with slow fluctuations with power spectral densities inversely proportional to the frequency in the frequency range of 0.02-1.0 Hz, during the paradoxical sleep. This confirms that the characteristics of fluctuations in neuronal activities of the mesencephalic reticular formation observed in our previous study are more general phenomena in the cat''s brain. Partly similar behavior of spectral densities is also observed during the alert state. These observations are quantitatively confirmed by the statistical time series analysis of the spike density provesses of spontaneous activities.

关键词： Hippocampus Ventrobasal complex Spontaneous discharge Sleep-wakefulness 1/ f fluctuation

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HIGH MITE-ALLERGEN EXPOSURE INCREASES THE RISK Of SENSITIZATION IN ATOPIC CHILDREN AND YOUNG-ADULTS

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JOURNAL Of ALLERGY AND CLINICAL IMMUNOLOGY 1989年第5期84卷 718-725页

作者： LAU, S fALKENHORST, G WEBER, A WERTHMANN, I LIND, P BUETTNERGOETZ, P WAHN, U PROT LAB COPENHAGEN DENMARK INST MED STAT & INFORMAT STEGLITZ BERLIN FED REP GER

Concentrations of major allergens of Dermatophagoides pteronyssinus (Dpt) and D. farine (Df), Der I and Der f I, were determined in 183 dust samples of mattresses of 133 atopic and 50 nonatopic children by a sandwich-type ELISA. Atopic children and young adults living in houses with high levels of Der p I and Der f I (.gtoreq. 2000 ng/gm of dust) were found to have significantly higher serum IgE levels to Dpt and Df (p < 0.0001) compared to patients with low mite-allergen exposure. Washed leukocytes of 55 atopic children and 14 control subjects were investigated for in vitro histamine release to serial dilutions of Der p I: 86% of highly exposed (.gtoreq. 10,000 ng/gm) children demonstrated positive histamine release in response to Der p I compared to 17% in the group with very low exposure (< 400 ng/gm). There was a positive correlation between basophil sensitivity (rs = 0.6;p < 0.0001) and reactivity (rs = 0.54;p < 0.0001) to Derp p I and mite-allergen exposure. The relative risk for sensitization in the highly exposed group versus the group with very low exposure was sevenfold to 32-fold increased. We conclude that high concentrations of mite allergen (.gtoreq. 2000 ng/gm) increase the risk of specific sensitization in atopic children and young adults and thus may facilitate allergic airway decrease.

关键词： Der p I Antigen P 1 of Dermatophagoides pteronyssinus Der f I Antigen f 1 of Dermatophagoides farinae Dpt Dermatophagoides pteronyssinus Df Dermatophagoides farinae Der m I Antigen M 1 of Dermatophagoides microceras Dm Dermatophagoides microceras HR Histamine release BHR 30 Antigen concentration in micrograms per milliliter required to release 30% histamine (basophil sensitivity) BHR 20 Antigen concentration in micrograms per milliliter required to release 20% histamine PIPES Piperazine- N N′ -bis-2-ethanesulfonic acid

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