bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of parathion residues in rice samples using a ﬂow injection chemiluminescence method
Authors: Liu Xiaoyu , Du Jianxiu , Lu Jiuru 
Published: October 2003

AbstractA sensitive ﬂow injection chemiluminescence method is described for the determination of parathion pesticide, based upon its direct chemiluminescence reaction with luminol and hydrogen peroxide in the presence of non‐ionic surfactant polyethylene glycol 400. Under the selected experimental conditions, the concentration of parathion is proportional to the CL intensity in the range 0.02–1.0 mg/L. The detection limit was 0.008 mg/L and the relative standard deviation was 2.8% for 0.2 mg/L parathion solution (n = 11). This method was successfully applied to the determination of parathion residue in rice samples. Copyright © 2003 John Wiley & Sons, Ltd.
Optimization of peroxynitrite–luminol chemiluminescence system for detecting peroxynitrite in cell culture solution exposed to carbon disulphide
Authors: Chen Shao L. , Jian Le , Lang Hui Q. 
Published: October 2003

AbstractWe established a peroxynitrite–luminol chemiluminescence system for detecting peroxynitrite in cell culture solution exposed to carbon disulphide (CS2). Three factors, including exposure time to ozone (Factor A), volume of peroxynitrite (ONOO−) solution (Factor B) and luminol concentrations (Factor C) at three levels were selected and the combinations were in accordance with orthogonal design L9 (34). Peroxynitrite was generated from the reaction of ozone and 0.01 mol/L sodium azide (NaN3) dissolved in carbonic acid buffer solution (pH 11), and it was reacted with luminol to yield chemiluminescence. The peak value, peak time and kinetic curve of the light emission were observed. The selected combination conditions were 50 s ozone, 800 µL peroxynitrite and 0.001 mol/L luminol solution. Cell culture solution with CS2 enhanced the emission intensity of chemiluminescence (F = 8.38, p = 0.018) and shortened the peak time to chemiluminescence (F = 139.00, p = 0.0001). The data demonstrated that this luminol chemiluminescence system is suitable for detecting peroxynitrite in cell culture solutions for evaluating the effect of CS2 on endothelial cells. Copyright © 2003 John Wiley & Sons, Ltd.
In vivo monitoring of chlorophyll ﬂuorescence response to low‐dose γ‐irradiation in pumpkin (cucurbita pepo) leaves
Authors: Jovanić B. R. , Dramićanin M. D. 
Published: October 2003

AbstractThe effect of γ‐irradiation on the in vivo‐measured chlorophyll ﬂuorescence in a pumpkin leaves (Cucurbita pepo) has been investigated. Plants were grown in the same environment, then divided into several groups and irradiated at ambient conditions at small dose levels (up to 13.4 Gy) with 60Co γ‐rays. The post‐irradiation effect on chlorophyll status in the leaves was examined by measuring chlorophyll ﬂuorescence 2 days (48 h) after exposure. It is undoubtedly found that the value of ﬂuorescence intensity ratio (FIR) at 690 nm and 735 nm (F690/F735) depends upon the ionizing radiation dose. Even with the smallest dose of 3.35 Gy, ionizing radiation notably altered the ﬂuorescence spectra of leaves. The spectra difference was manifested by decrease of FIR due to changed chlorophyll luminescence, the possible reason for which could be increase of chlorophyll concentration during the recovery process of the plant. The potential implications of these results for plant physiological status monitoring, as well as for pollution detection and assessment, are discussed in brief. Copyright © 2003 John Wiley & Sons, Ltd.
Interaction of clinically important human DNA topoisomerase I poison, topotecan, with double‐stranded DNA
Authors: Streltsov Sergei , Oleinikov Vladimir , Ermishov Mikhail , Mochalov Konstantin , Sukhanova Alyona , Nechipurenko Yuri , Grokhovsky Sergei , Zhuze Alexei , Pluot Michel , Nabiev Igor 
Published: October 2003

AbstractTopotecan (TPT), a water‐soluble derivative of camptothecin, is a potent antitumor poison of human DNA topoisomerase I (top1) that stabilizes the cleavage complex between the enzyme and DNA. The role of the recently discovered TPT affinity to DNA remains to be defined. The aim of this work is to clarify the molecular mechanisms of the TPT‐DNA interaction and to propose the models of TPT‐DNA complexes in solution in the absence of top1. It is shown that TPT molecules form dimers with a dimerization constant of (4.0 ± 0.7) × 103M−1 and the presence of DNA provokes more than a 400‐fold increase of the effective dimerization constant. Flow linear dichroism spectroscopy accompanied by circular dichroism, fluorescence, and surface‐enhanced Raman scattering experiments provide evidence that TPT dimers are able to bind DNA by bridging different DNA molecules or distant DNA structural domains. This effect may provoke modification of the intrinsic geometry of the cruciform DNA structures, leading to the appearance of new crossover points that serve as the sites of the top1 loading position. The data presume the hypothesis of TPT‐mediated modulation of top1‐DNA recognition before ternary complex formation. © 2003 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy), 2003
3′‐Azido‐3′‐deoxythymidine binding to ribonuclease A: Model for drug‐protein interaction
Authors: Gaudreau S. , Novetta‐Dellen A. , Neault J. F. , Diamantoglou S. , Tajmir‐Riahi H. A. 
Published: October 2003

AbstractRibonuclease A (RNase A) with several high affinity binding sites is a possible target for many organic and inorganic molecules. 3′‐Azido‐3′‐deoxythymidine (AZT) is the first clinically effective drug for the treatment of human immunodeficiency virus (HIV) infection. The drug interactions with protein and nucleic acids are associated with its mechanism of action in vivo. This study was designed to examine the interaction of AZT with RNase A under physiological conditions. Reaction mixtures of constant protein concentration (2%) and different drug contents (0.0001–0.1 mM) are studied by UV‐visible, FTIR, and circular dichroism spectroscopic methods in order to determine the drug binding mode, the drug binding constant, and the effects of drug complexation on the protein and AZT conformations in aqueous solution. The spectroscopic results showed one major binding for the AZT‐RNase complexes with an overall binding constant of 5.29 × 105 M−1. An increase in the protein α helicity was observed upon AZT interaction, whereas drug sugar pucker remained in the C2′‐endo/anti conformation in the AZT‐RNase complexes. © 2003 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy), 2003
Structural changes of low density lipoproteins with Cu2+ and glucose induced oxidation
Authors: Gallego‐Nicasio J. , López‐Rodríguez G. , Martínez R. , Tarancón M. J. , Fraile M. V. , Carmona P. 
Published: October 2003

AbstractThe compositional and structural changes of lipids and apolipoproteins during in vitro oxidation of low density lipoprotein (LDL) are investigated in this study by IR spectroscopy. For comparison, LDL samples containing either copper or glucose at physiological or pathological concentrations are considered in order to know the separate affects of these chemical factors on LDL oxidation. The results show that the initial steps of lipid oxidation proceed through hydrogen atom loss from methylene groups, as well as loss of cholesteryl ester molecules, and later a recovering of carbonyl compounds resulting from aldehyde formation that generally occurs in autooxidation processes. Lipid oxidation is induced by copper ions, and glucose enhances metal ion induced LDL oxidation as determined by conjugated diene formation. As to the protein conformational changes, IR spectroscopy reveals for the first time that LDL oxidation involves formation of β‐sheet structures, these being more abundant in LDL samples with pathological concentrations of glucose or copper. Consequently, the LDL structural changes may contribute to the recognition of oxidized LDL particles by scavenger receptors. © 2003 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy) 72: 514–520, 2003
Distinguishing and grading human gliomas by IR spectroscopy
Authors: Steiner Gerald , Shaw Anthony , Choo‐Smith Lin‐P'ing , Abuid Mario H. , Schackert Gabriele , Sobottka Stephan , Steller Wolfram , Salzer Reiner , Mantsch Henry H. 
Published: October 2003

AbstractAs a molecular probe of tissue composition, IR spectroscopy can potentially serve as an adjunct to histopathology in detecting and diagnosing disease. This study demonstrates that cancerous brain tissue (astrocytoma, glioblastoma) is distinguishable from control tissue on the basis of the IR spectra of thin tissue sections. It is further shown that the IR spectra of astrocytoma and glioblastoma affected tissue can be discriminated from one another, thus providing insight into the malignancy grade of the tissue. Both the spectra and the methods employed for their classification reveal characteristic differences in tissue composition. In particular, the nature and relative amounts of brain lipids, including both the gangliosides and phospholipids, appear to be altered in cancerous compared to control tissue. Using a genetic classification approach, classification success rates of up to 89% accuracy were obtained, depending on the number of regions included in the model. The diagnostic potential and practical applications of IR spectroscopy in brain tumor diagnosis are discussed. © 2003 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy), 2003
Individual tyrosine side‐chain contributions to circular dichroism of ribonuclease
Authors: Woody A‐Young Moon , Woody Robert W. 
Published: October 2003

AbstractExperimental and theoretical studies using site‐directed mutants of ribonuclease A (RNase A) offer more extensive information on the tyrosine side‐chain contributions to the circular dichroism (CD) of the enzyme. Bovine pancreatic RNase A has three exposed tyrosine residues (Tyr73, Tyr76, and Tyr115) and three buried tyrosine residues (Tyr25, Tyr92 and Tyr97). The difference CD spectra between the wild type and the mutants at pH 7.0 (Δϵ277,wt − Δϵ277,mut) show bands with more negative ΔΔϵ277 values for Y73F and Y115F than those for Y25F and Y92F and bands with positive ΔΔϵ277 values for Y76F and Y97F. The theoretical calculations are in good semiquantitative agreement for all the mutants. The pH difference spectrum (pH 11.3 − 7.0) for the wild type shows a negative band at 295 nm and an enhanced positive band at 245 nm. The three mutants at buried tyrosine sites and one mutant at an exposed tyrosine site (Y76F) exhibit pH‐difference spectra that are similar to that of the wild type. In contrast, two mutants at exposed tyrosine sites (Y73F and Y115F) exhibit diminished 295‐nm negative bands and, instead of positive bands at 245 nm, negative bands are observed. Our results indicate that Tyr73 and Tyr115, two of the exposed tyrosine residues, are the largest contributors to the 277‐ and 245‐nm CD bands of RNaseA, but the buried tyrosine residues and the one remaining exposed residue also contribute to these bands. Disulfide contributions to the 277‐ and 240‐nm bands and the peptide contribution to the 240‐nm band are confirmed theoretically. © 2003 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy) 72: 500–513, 2003
Sulawesi: Solargetriebene Meeresnacktschnecken und wurmgleiche Sand‐Hinterkiemer
Authors: Schrödl Michael , Eheberg Dirk , Burghardt Ingo 
Published: October 2003

AbstractIm Juli diesen Jahres startete eine internationale Expedition zur erstmaligen Bioinventur des Bunaken National Park bei der indonesischen Insel Sulawesi. Biologen der Zoologischen Staatssammlung München, des GeoBioCenters LMU, der Ruhr‐Uni Bochum und der Sam Ratulangi‐University Manado, Sulawesi, entdeckten dabei eine überwältigende Artenvielfalt mariner Mollusken.
Aktenzeichen Y: …gelöst
Authors: Kronberg Inge 
Published: October 2003

AbstractDas menschliche Genom galt schon im April 2003 zu 99 Prozent als entschlüsselt, aber erst Monate später wurde die Sequenz des Y‐Chromosoms nachgeliefert. Der Grund: Das Y‐Chromosom gehört zu jenen Teilen des Genoms, die sich den Standard‐Techniken entziehen, weil es sich zu einem großen Teil um heterochromatische Regionen mit hochrepetitiven Sequenzen handelt.
Hummeln — Hast macht schlampig
Authors: Irsch Wilhelm 
Published: October 2003

AbstractPedanten und Schlamper gibt es auch bei Hummeln, wie Zoologen bei Untersuchungen des Lernverhaltens von Erdhummeln (Bombus terrestris) feststellten. Die sorgfältigen Tiere lassen sich bei der Futtersuche Zeit und wählen mit hoher Präzision geeignete Futterquellen aus. Schlampige Hummeln dagegen hasten von Blüte zu Blüte und machen dabei viele Fehler.
Intra‐ and intersectoral effects in environmental disclosures: evidence for legitimacy theory?
Authors: Campbell David 
Published: October 2003

AbstractEnvironmental disclosures were recorded from the annual reports of a sample of ten UK FTSE 100 companies in five sectors between 1974 and 2000. ‘Environmental sensitivity’ was employed as a proxy for corporate vulnerability to environmental concern, and intra‐ and intersectoral differences were tested for in the belief that difference in industry response will signify differing perceptions on the need to provide voluntary disclosure and hence restore or maintain legitimacy. Intrasectoral agreements at given points in time were also taken to be evidence for legitimacy theory in that more than one company in a sector perceived a need to change disclosure behaviour at the same time. Legitimacy theory as an explicator for variability in environmental disclosure is supported. Copyright © 2003 John Wiley & Sons, Ltd and ERP Environment.
A critical assessment of how non‐governmental organizations use the capital markets to achieve their aims: a UK study
Authors: Waygood Steve , Wehrmeyer Walter 
Published: October 2003

AbstractNon‐governmental organizations (NGOs) increasingly attempt to use the capital markets to further their aims. This paper proposes a taxonomy for such intervention that is based on two distinct strategies: a macro capital redistribution strategy and a micro investor influence strategy, both of which can be undertaken either directly or indirectly. The paper reviews empirical evidence of the success of each strategy through four case studies. It concludes by suggesting that there is some empirical evidence that the typology can be successfully applied and that there is some initial evidence that NGO capital market engagement strategies have, in certain circumstances, successfully changed business strategy. Copyright © 2003 John Wiley & Sons, Ltd and ERP Environment.
Cell type‐ and region‐specific expression of protein kinase C‐substrate mRNAs in the cerebellum of the macaque monkey
Authors: Higo Noriyuki , Oishi Takao , Yamashita Akiko , Matsuda Keiji , Hayashi Motoharu 
Published: October 2003

AbstractWe performed nonradioactive in situ hybridization histochemistry in the monkey cerebellum to investigate the localization of protein kinase C‐substrate (growth‐associated protein‐43 [GAP‐43], myristoylated alanine‐rich C‐kinase substrate [MARCKS], and neurogranin) mRNAs. Hybridization signals for GAP‐43 mRNA were observed in the molecular and granule cell layers of both infant and adult cerebellar cortices. Signals for MARCKS mRNA were observed in the molecular, Purkinje cell, and granule cell layers of both infant and adult cortices. Moreover, both GAP‐43 and MARCKS mRNAs were expressed in the external granule cell layer of the infant cortex. In the adult cerebellar vermis, signals for both GAP‐43 and MARCKS mRNAs were more intense in lobules I, IX, and X than in the remaining lobules. In the adult hemisphere, both mRNAs were more intense in the flocculus and the dorsal paraflocculus than in other lobules. Such lobule‐specific expressions were not prominent in the infant cerebellar cortex. Signals for neurogranin, a postsynaptic substrate for protein kinase C, were weak or not detectable in any regions of either the infant or adult cerebellar cortex. The prominent signals for MARCKS mRNA were observed in the deep cerebellar nuclei, but signals for both GAP‐43 and neurogranin mRNAs were weak or not detectable. The prominent signals for both GAP‐43 and MARCKS mRNAs were observed in the inferior olive, but signals for neurogranin were weak or not detectable. The cell type‐ and region‐specific expression of GAP‐43 and MARCKS mRNAs in the cerebellum may be related to functional specialization regarding plasticity in each type of cell and each region of the cerebellum. J. Comp. Neurol. 467:135–149, 2003. © 2003 Wiley‐Liss, Inc.
Evidence that the bed nucleus of the stria terminalis contributes to the modulation of hypophysiotropic corticotropin‐releasing factor cell responses to systemic interleukin‐1β
Authors: Crane James W. , Buller Kathryn M. , Day Trevor A. 
Published: October 2003

AbstractSystemic infection activates the hypothalamic‐pituitary‐adrenal (HPA) axis, and brainstem catecholamine cells have been shown to contribute to this response. However, recent work also suggests an important role for the central amygdala (CeA). Because direct connections between the CeA and the hypothalamic apex of the HPA axis are minimal, the present study investigated whether the bed nucleus of the stria terminalis (BNST) might act as a relay between them. This was done by using an animal model of acute systemic infection involving intravascular delivery of the proinflammatory cytokine interleukin‐1β (IL‐1β, 1 μg/kg). Unilateral ibotenic acid lesions encompassing the ventral BNST significantly reduced both IL‐1β‐induced increases in Fos immunoreactivity in corticotropin‐releasing factor (CRF) cells of the hypothalamic paraventricular nucleus (PVN) and corresponding increases in adrenocorticotropic hormone (ACTH) secretion. Similar lesions had no effect on CRF cell responses to physical restraint, suggesting that the effects of BNST lesions were not due to a nonspecific effect on stress responses. In further studies, we examined the functional connections between PVN, BNST, and CeA by combining retrograde tracing with mapping of IL‐1β‐induced increases in Fos in BNST and CeA cells. In the case of the BNST, these studies showed that systemic IL‐1β administration recruits ventral BNST cells that project directly to the PVN. In the case of the CeA, the results obtained were consistent with an arrangement whereby lateral CeA cells recruited by systemic IL‐1β could regulate the activity of medial CeA cells projecting directly to the BNST. In conclusion, the present findings are consistent with the hypothesis that the BNST acts as a relay between the CeA and PVN, thereby contributing to CeA modulation of hypophysiotropic CRF cell responses to systemic administration of IL‐1β. J. Comp. Neurol. 467:232–242, 2003. © 2003 Wiley‐Liss, Inc.
Connections of the posterior thalamic region with the auditory ectosylvian cortex in the dog
Authors: Malinowska Monika , Kosmal Anna 
Published: October 2003

AbstractThe purpose of the present study was to define auditory cortical areas in the dog on the basis of thalamocortical connectivity patterns. Connections between the posterior thalamic region and auditory ectosylvian cortex were studied using axonally transported tracers: fluorochromes and biotinylated dextran amine. Cyto‐ and chemoarchitecture provided grounds for the division of the posterior thalamic region into three complexes, medial geniculate body (MGB), posterior nuclei (Po), and lateromedial and suprageniculate nuclei (LM‐Sg). Distinctive cytoarchitectonic features and the distribution of dominant thalamocortical connections (determined quantitatively) allowed us to define four ectosylvian areas: middle (EM), anterior (EA), posterior (EP), and composite (CE). We found that each area was a place of convergence for projections from five to eleven nuclei of the three thalamic complexes, with dominant projections derived from one or two nuclei. Dominant topographical projections from the ventral nucleus to area EM confirmed physiological reports that it may be considered a primary auditory area (AI). We found the anterior part of the EM to be distinct in having unique strong connections with the deep dorsal MGB nucleus. Area EA, which receives dominant projections from the lateral Po (Pol) and medial MGB nuclei, as well as area EP, which receives dominant connections from the dorsal caudal MGB nucleus, compose two parasensory areas. Area CE receives dominant projections from the extrageniculate nuclei, anterior region of the LM‐Sg, and Pol, supplemented with an input from the somatosensory VP complex, and may be considered a polymodal association area. J. Comp. Neurol. 467:185–206, 2003. © 2003 Wiley‐Liss, Inc.
Absence of circadian clock regulation of horizontal cell gap junctional coupling reveals two dopamine systems in the goldfish retina
Authors: Ribelayga Christophe , Mangel Stuart C. 
Published: October 2003

AbstractIn fish and other vertebrate retinas, although dopamine release is regulated by both light and an endogenous circadian (24‐hour) clock, light increases dopamine release to a greater extent than the clock. The clock increases dopamine release during the subjective day so that D2‐like receptors are activated. It is not known, however, whether the retinal clock also activates D1 receptors, which display a much lower sensitivity to dopamine in intact tissue. Because activation of the D1 receptors on fish cone horizontal (H1) cells uncouples the gap junctions between the cells, we studied whether the clock regulates the extent of biocytin tracer coupling in the goldfish retina. Tracer coupling between H1 cells was extensive under dark‐adapted conditions (low scotopic range) and similar in the subjective day, subjective night, day, and night. An average of approximately 180 cells were coupled in each dark‐adapted condition. However, bright light stimulation or application of the D1 agonist SKF38393 (10 μM) dramatically reduced H1 cell coupling. The D2 agonist quinpirole (1 μM) or application of the D1 antagonist SCH23390 (10 μM) and/or the D2 antagonist spiperone (10 μM) had no effect on H1 cell coupling in dark‐adapted retinas. These observations demonstrate that H1 cell gap junctional coupling and thus D1 receptor activity are not affected by endogenous dopamine under dark‐adapted conditions. The results suggest that two different dopamine systems are present in the goldfish retina. One system is controlled by an endogenous clock that activates low threshold D2‐like receptors in the day, whereas the second system is controlled by light and involves activation of higher threshold D1 receptors. J. Comp. Neurol. 467:243–253, 2003. © 2003 Wiley‐Liss, Inc.
Syntheses, Structure and Magnetic Properties of the First µ1,5‐Dicyanamido‐Bridged Dinuclear Compounds [Ni(µ1,5‐dca)(dca)(dpt)]2 and [Ni(µ1,5‐dca)(dca)(medpt)]2
Authors: Ghoshal Debajyoti , Bialas Hanna , Escuer Albert , Font‐Bardía Mercé , Maji Tapas Kumar , Ribas Joan , Solans Xavier , Vicente Ramon , Zangrando Ennio , Chaudhuri Nirmalendu Ray 
Published: October 2003

AbstractThe first structural determination of dinuclear compounds with μ1,5‐dicyanamide [dca, N(CN)2−] as bridging ligand has been achieved with the products of formula [Ni(µ1,5‐dca)(dca)(dpt)]2 (1) and [Ni(µ1,5‐dca)(dca)(medpt)]2 (2) [dpt = bis(3‐aminopropyl)amine and medpt = bis(3‐aminopropyl)methylamine]. The X‐ray diffraction analysis reveals dinuclear compounds with double μ1,5‐dicyanamide bridges. The nickel atoms are hexacoordinate. The small differences in the terminal ligand (dpt or medpt) create a drastic change in the magnetic behaviour: the susceptibility measurements of 1 show weak antiferromagnetic coupling (J = −1.2 cm−1, g = 2.29) whereas those of 2 show ferromagnetic coupling (J = 0.7 cm−1, g = 2.17). The related compound (μ‐terephthalato)[Ni(dca)(dpt)(H2O)]2 (3) is also described. The X‐ray diffraction analysis reveals a dinuclear terephthalato‐bridged NiII compound with terminal dca ligands. The susceptibility measurements of 3 indicate weak antiferromagnetic coupling: J = −0.3 cm−1, g = 2.13. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)