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  • 1990-1994  (9)
  • 1975-1979  (11)
  • 1905-1909  (3)
  • Chemistry  (15)
  • Life and Medical Sciences  (6)
  • Allelopathy
  • Biochemistry and Biotechnology
  • synergism
  • 1
    Electronic Resource
    Electronic Resource
    Synergistic inhibitory effects ofp-coumaric and ferulic acids on germination and growth of grain sorghum (1977)
    Springer
    Journal of chemical ecology 3 (1977), S. 197-205 
    Details
    ISSN: 1573-1561
    Keywords: synergism ; ferulic acid ; p-coumaric acid ; allelopathy ; phytotoxicity ; inhibition ; sorghum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The data support the hypothesis that there is a synergistic phytotoxic effect whenp-coumaric and ferulic acids are found together. Equimolar mixtures of both acids showed greater reduction in sorghum seed germination, shoot elongation, and total seedling growth than either phytotoxin caused when alone. Repeated experiments showed mixtures containing 5×10−3 Mp-coumaric and 5×10−3 M ferulic acids reduced germination to 34% of controls after 24 hr and 59% by 48 hr. The same concentration of either phenol-treated seeds alone showed 69 and 92% germination at comparable times. The phytotoxic action of the combination approximated the inhibitory effect on germination of 10−2 M ferulic acid and was a greater reduction than caused by 10−2 Mp-coumaric treatments. Sorghum seedling growth was more sensitive than germination, with an equimolar mixture of 2.5×10−4 Mp-coumaric and 2.5×10−4 M ferulic acids reducing seedling dry weight significantly below weights of seedlings treated separately with 2.5×10−4 Mp-coumaric or ferulic acids. Further dilutions showed a 1.25×10−4 M concentration of either phenol was stimulatory to seedling growth, whereas a mixture of these two produced inhibition.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00994146
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  • 2
    Electronic Resource
    Electronic Resource
    Synergistic inhibitory effects of vanillic andp-hydroxybenzoic acids on radish and grain sorghum (1978)
    Springer
    Journal of chemical ecology 4 (1978), S. 425-436 
    Details
    ISSN: 1573-1561
    Keywords: synergism ; vanillic acid ; p-hydroxybenzoic acid ; allelopathy ; inhibition ; sorghum ; radish
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Radish and grain sorghum germination and sorghum growth were inhibited in a synergistic manner by combinations of vanillic andp-hydroxybenzoic acids. At threshold inhibition levels, 2.5 × 10−3 M vanillic acid-treated radish seeds had 71 % of control germination after 24 hr and 2.5 × 10−3 Mp-hydroxybenzoic acid-treated radish yielded 95% germination. A mixture of 2.5 × 10−3 M of each of these two phytotoxins showed 52% germination after 24 hr. Equimolar mixtures of 5 × 10−3 M vanillic andp-hydroxybenzoic acids allowed sorghum germination of 60% of untreated seeds after 24 hr, whereas separate treatments of individual phenols had 93% and 96% of control seed germination. Sorghum root and shoot elongation and total seedling growth were more sensitive than germination to vanillic andp-hydroxybenzoic acid treatments, and synergistic effects also were apparent. A combination of 5 × 10−3 M vanillic with 5 × 10−3 Mp-hydroxybenzoic reduced root length more than either did individually, and a mixture of 5 × 10−4 M vanillic with 5 × 10−4 Mp-hydroxybenzoic acid reduced sorghum seedling growth to approximately that resulting from a 10−3 M concentration of either phenol alone. Phytotoxin levels inhibitory to sorghum growth caused small increases in lower leaf surface diffusive resistance, but did not close stomates, and this effect was not judged to be the cause of reduced sorghum growth.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00989499
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  • 3
    Electronic Resource
    Electronic Resource
    The nature of the branches in poly(vinyl chloride)Dedicated to Prof. Dr. H. Mark on his 80th birthday (1975)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 1 (1975), S. 227-234 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: IR-spektroskopische Untersuchungen von Polyäthylen-Proben, dargestellt durch Reduktion von Polyvinylchlorid mit Lithiumaluminiumhydrid, ließen darauf schließen, daß Polyvinylchlorid Seitenketten enthält, die seine Morphologie und Festkörpereigenschaften wesentlich beeinflussen. Die Natur dieser Seitenketten war bisher unbekannt. Es wird anhand von 13C-NMR Spektren gezeigt, daß die Verzweigungen in reduziertem Polyvinylchlorid aus Methylgruppen bestehen, die vermutlich aus Chlormethylgruppen des ursprünglichen Polymeren entstanden sind. Die untersuchte Probe enthielt ca. 3 CH3-Gruppen pro 1000 CH2-Gruppen, jedoch is dieses Verhältnis vermutlich von der Polymerisationstemperatur abhängig. Zusätzlich wurden Anzeichen für längere Seitenketten gefunden, die allerdings nur in einem Ausmaß von weniger als 1 pro 1000 CH2-Gruppen vorhanden sein dürften.
    Notes: The presence of branches in poly(vinyl chloride) as indicated by previous IR measurements on the polymer reduced to polyethylene by means of lithium aluminum hydride is believed to affect materially the morphology and solid state properties of poly(vinyl chloride); however, up to the present, the nature of these branches has not been known. By use of 13C-NMR on reduced poly(vinyl chloride) it is demonstrated that the brances are methyl groups, presumably corresponding to chloromethyl groups in the original polymer. In the sample studied, the frequency is ca. 3 methyl groups per 1000 CH2 groups, but this is expected to depend on the temperature of polymerization. There is also some evidence for long branches, probably not exceeding 1 per 1000 CH2 groups.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1975.020011975115
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  • 4
    Electronic Resource
    Electronic Resource
    Crystallization and preliminary X-ray diffraction studies of human salivary α-amylase (1991)
    New York, NY : Wiley-Blackwell
    Proteins: Structure, Function, and Genetics 11 (1991), S. 230-232 
    Details
    ISSN: 0887-3585
    Keywords: parotid saliva ; enzyme ; crystals ; X-ray analysis ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Nonglycosylated α-amylase, a major component of human parotid saliva, has been crystallized by the vapor diffusion technique using 2-methyl-2,4-pentanediol as the precipitant in the presence of CaCl2 at pH 9.0. The crystals are orthorhombic, space group P212121 with unit cell dimensions of a = 53.3, b = 75.8, and c = 138.1 Å. The asymmetric unit contains one amylase molecule. The solvent content is 54%. The crystals are stable to X-rays and diffract up to 2.8 Å and appear to be suitable for X-ray diffraction studies.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prot.340110308
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  • 5
    Electronic Resource
    Electronic Resource
    Kinetic energy effects in an ion ensemble subjected to mass-selective isolation and resonance excitation: A simulation study (1993)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 28 (1993), S. 499-509 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A simulation study is described of the behaviour of ions confined in a quadrupole ion trap during each of two separate operations of a tandem mass spectrometric experiment. The two operations are those of mass-selective ion isolation and mass-selective resonance excitation to the point of ion ejection from the ion trap. The method of mass-selective ion isolation simulated is that of consecutive ion isolation. Simulation data indicate that the collisional history of the ions prior to the isolation process can greatly influence the degree to which ions survive this process. Simulation data for mass-selective resonance ejection are compared with experimental data obtained with a Finnigan-MAT ion trap mass spectrometer. In each operation, the facility with which ions absorb energy from the field within the ion trap, whether this field is derived from the R.F. drive potential or a supplementary potential, can determine the extent to which ions are retained within the ion trap during the two mass-selective operations described.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210280506
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  • 6
    Electronic Resource
    Electronic Resource
    Assignment of the histidine 12-threonine 45 hydrogen-bonded proton in the nmr spectrum of ribonuclease A in H2O (1975)
    New York : Wiley-Blackwell
    Biopolymers 14 (1975), S. 959-974 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Described herein are proton nmr experiments on chemically modified derivatives of ribonuclease A designed to elucidate the origin of an exchangeable resonance, assigned previously to a histidine ring N proton that titrates between 11 to 13 ppm with a pKa of 6.1 in H2O solution. Histidines 48 and 105, which are distant from the active site, are eliminated as candidates for this resonance from inhibitor binding studies on the enzyme in acetate-water solutions. This exchangeable resonance titrates with modified pKa's and constant area over the above pH range in His-119-N1-carboxymethylated-RNase A and des-(121-124)-RNase A, thus eliminating the imidazole N3 proton in the His 119-Asp 121 hydrogen bond. In His-12-N1-carboxymethylated-RNase A, this resonance is also observable, but broadens on raising the pH above 7 and at elevated temperatures above neutrality. It exhibits a pH-independent chemical shift characteristic of the protonated state of histidine. On the basis of these findings, this exchangeable resonance, designated a, is assigned to the imidazole N1 proton of His 12, which is hydrogen-bonded to the carbonyl oxygen of Thr 45 in the crystal.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1975.360140506
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  • 7
    Electronic Resource
    Electronic Resource
    Reassignment of the active site histidines in ribonuclease A by selective deuteration studies (1975)
    New York : Wiley-Blackwell
    Biopolymers 14 (1975), S. 987-997 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The C2H resonance of the active site histidine residue designated AS-2, which has the lower pKa of the two active site histidines, has been correlated in both RNase A and RNase S by comparing the pH 3 to 5.5 regions of the chemical shift titration curves, the effect of the inhibitor CMP-3′ on the chemical shifts at pH 4.0, and the effect of Cu II on the line widths at pH 3.6. It has been demonstrated that resonance AS-2 is absent in the spectrum of RNase S′ reconstituted using S-peptide deuterated at the C2 of His 12, and in that of the RNase S′-CMP-3′ complex. We thus demonstrate that histidine AS-2 is in fact His 12 in both enzymes. This finding is in agreement with out previous assignment of the exchangeable NH proton in RNase A to His 12, but reverses the assignments of the active site histidine C2H resonances made earlier by other authors.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1975.360140508
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  • 8
    Electronic Resource
    Electronic Resource
    Renal regeneration following D-serine induced acute tubular necrosisSupported by the Chicago and Illinois Heart Association. (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 193 (1979), S. 383-387 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Regeneration of the rat kidney was observed for six days after inducing acute tubular necrosis of the proximal pars recta with d-serine (80 mg/100g body weight). Regenerating cells appear by two days post-treatment, and re-epithelialization of the nephron is completed within six days, with the most mature cells approaching normal morphology. Regeneration originates from viable cells adjacent to the necrotic zone which divide and follow a template provided by the intact basement membrane. Transient, cytoplasmic regenerative activity among developing tubular cells is characterized by the presence of large, irregularly shaped nuclei, prominent nucleoli, abundant ribosomes and lysosomes, and abnormal mitochondrial configurations. Microfilaments appear to be involved in the formation of apical microvilli and the basal labyrinth of plasmalemmal convolutions. These data suggest that d-serine. inducedacute tubular necrosis of the proximal pars recta may be followed by rapid, patterned regeneration along an intact basement membrane, and that microfilaments are involved in differentiation of cellular morphology.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1091930305
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  • 9
    Electronic Resource
    Electronic Resource
    Transient expression of the cytochrome P450 aromatase gene in elongating porcine blastocysts is correlated with uterine insulin-like growth factor levels during peri-implantation development (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 37 (1994), S. 1-11 
    Details
    ISSN: 1040-452X
    Keywords: IGF-I ; IGF-II ; Uterus ; Embryo ; Estrogens ; Aromatase P450 ; Pregnancy ; RIA ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The insulin-like growth factors (IGFs-I and -II) are mediators of cellular growth and differentiation. The expression of these growth factor genes is temporally and hormonally regulated in the uterus during pregnancy, suggesting potentially important roles in embryonic development, implantation, and successful progression of pregnancy. A known regulator of uterine IGF-I secretion is estrogen, which is produced by pre-implantation mammalian embryos of several species and whose amounts may be influenced by growth factors via their effects on the transcriptional activities of steroidogenic enzyme genes. We have previously proposed that within the uterine microenvironment, a positive feedback loop may link uterine secretion of IGFs with embryonic production of estrogens to maintain and coordinate the timing of biological signals essential for embryo development. The present study examined the temporal relationships between the levels of conceptus cytochrome P450 aromatase mRNA and protein and concentrations of IGF-I and -II in uterine luminal fluids of pigs. A DNA fragment encoding a highly conserved region among mammalian aromatase P450 proteins was isolated by hybridization screening of a porcine genomic DNA library with a human aromatase P450 cDNA fragment as probe. A synthetic oligopeptide DDVIDGYPVKKGTNI within this highly conserved region was used to generate an antiserum in sheep that recognized a protein of Mr 49,000 in Western blot analysis of porcine ovarian, placental, endometrial, and conceptus extracts. A radioimmunoassay (RIA) for aromatase P450 was established and validated using this antiserum. RIA demonstrated highest levels of aromatase P450 protein in extracts of days 10, 11, and 12 porcine conceptuses with significantly diminished levels in elongated conceptuses at days 15 and 18. In the conceptus, aromatase P450 was localized to the inner cell layer (hypoblast) of the trophectoderm. A major mRNA transcript of aproximately 3 kb in length was demonstrated by Northern blot analysis of conceptus RNA with a porcine aromatase P450 antisense RNA probe. The relative levels of aromatase P450 mRNA were higher in conceptuses at day 12 than at days 15 and 18, in parallel with the levels of aromatase P450 protein. RIA of uterine luminal fluids demonstrated maximal concentrations of IGF-I at day 12, which were significantly decreased by day 15, and increased concentrations of IGF-II by day 12, which were maintained until day 18 of pregnancy. These results demonstrate that the transient expression of conceptus aromatase P450 mRNA and protein in elongating pig blastocysts is coincident with their capacity to secrete estrogens and with the rapidly changing concentrations of IGFs withing the uterine microenvironment. These results suggest that regulation of aromatase P450 gene expression by IGFs may represent one mechanism by which uterine factors modulate an embryonic function (e.g., estrogen production) that elicits coordinate changes in the endometrium in preparation for implantation. © 1994 Wiley-Liss, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1080370102
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  • 10
    Electronic Resource
    Electronic Resource
    Rapid fixation and embedding method for immunocytochemical studies of tomato spotted wilt tospovirus (TSWV) in plant and insect tissues (1993)
    New York, NY [u.a.] : Wiley-Blackwell
    Microscopy Research and Technique 24 (1993), S. 514-520 
    Details
    ISSN: 1059-910X
    Keywords: Microwave energy ; Immunolabelling ; Antigenicity ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: A new rapid fixation and embedding technique using microwave energy was evaluated for immunolabelling and examination of ultrastructure of plant and insect cells. Tissues in gluteraldehyde-paraformaldehyde were fixed for fifteen seconds in a microwave at 100% power, and dehydrated. Microwave energy was then used to polymerize the London Resin White (LR White) acrylic resin during the embedding process. Embedded specimens were then thin sectioned (90 nm) and treated with anti-tomato spotted wilt tospovirus (TSWV) antiserum followed by protein A-gold label, or antisera against a TSWV encoded nonstructural protein followed by goat anti-rabbit gold label. Using this technique, structural and nonstructural proteins of TSWV were readily detected and specifically labelled in cells of the insect vector, the western flower thrips, Frankliniella occidentalis (Pergande), and in infected cells of the plant species, Emilia sonchifolia L. © 1993 Wiley-Liss, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jemt.1070240608
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