bluuebunny/crossref_metadata_2025_split huggingface dataset:
Overexpression of a Gene Encoding Hydrogen Peroxide-Generating Oxalate Oxidase Evokes Defense Responses in Sunflower
Authors: Hu Xu , Bidney Dennis L. , Yalpani Nasser , Duvick Jonathan P. , Crasta Oswald , Folkerts Otto , Lu Guihua 
Published: September 2003

Abstract
Oxalate oxidase (OXO) converts oxalic acid (OA) and O2 to CO2 and hydrogen peroxide (H2O2), and acts as a source of H2O2 in certain plant-pathogen interactions. To determine if the H2O2 produced by OXO can function as a messenger for activation of defense genes and if OXO can confer resistance against an OA-producing pathogen, we analyzed transgenic sunflower (Helianthus annuus cv SMF3) plants constitutively expressing a wheat (Triticum aestivum) OXO gene. The transgenic leaf tissues could degrade exogenous OA and generate H2O2. Hypersensitive response-like lesion mimicry was observed in the transgenic leaves expressing a high level of OXO, and lesion development was closely associated with elevated levels of H2O2, salicylic acid, and defense gene expression. Activation of defense genes was also observed in the transgenic leaves that had a low level of OXO expression and had no visible lesions, indicating that defense gene activation may not be dependent on hypersensitive response-like cell death. To further understand the pathways that were associated with defense activation, we used GeneCalling, an RNA-profiling technology, to analyze the alteration of gene expression in the transgenic plants. Among the differentially expressed genes, full-length cDNAs encoding homologs of a PR5, a sunflower carbohydrate oxidase, and a defensin were isolated. RNA-blot analysis confirmed that expression of these three genes was significantly induced in the OXO transgenic sunflower leaves. Furthermore, treatment of untransformed sunflower leaves with jasmonic acid, salicylic acid, or H2O2 increased the steady-state levels of these mRNAs. Notably, the transgenic sunflower plants exhibited enhanced resistance against the OA-generating fungus Sclerotinia sclerotiorum.
Influence of <i>Helicobacter pylori</i> Infection and Omeprazole Treatment on Gastric Regional CO<sub>2</sub>
Authors: Leodolter Andreas , Glasbrenner Bernhard , Wiedeck Heide , Eberhardt Holger , Malfertheiner Peter , Brinkmann Alexander 
Published: September 2003

<i>Background:</i> Gastric regional CO<sub>2</sub> accumulation indicates gastric mucosal hypoperfusion in critically ill patients. CO<sub>2</sub> is also a reaction product of urea degradation, and we therefore tested the hypothesis if regional pCO<sub>2</sub> is influenced by <i>Helicobacter pylori</i> infection. <i>Material:</i> Seven <i>H. pylori</i>-positive and 7 <i>H. pylori</i>-negative volunteers (age range 21–30 years) were investigated. During a 6- to 7-hour observation period, we obtained every 30 min arterial blood gases, gastric juice pH from a glass pH electrode and regional pCO2 from a gastric tonometer. The study protocol included subsequent periods of baseline measurements, pentagastrin stimulation (0.6 µg/kg/h/i.v.) and application of omeprazole (40 mg i.v.). <i>Results:</i> Gastric regional pCO<sub>2</sub> was increased in <i>H. pylori</i>-positive versus <i>H. pylori</i>-negative subjects before (64.4 ± 3.1 vs. 50.0 ± 2.9 mm Hg, p < 0.005) but not after application of omeprazole. The effect of omeprazole on gastric juice pH was increased in <i>H. pylori</i>-positive subjects (mean pH during 4 h 6.1 ± 0.3 in <i>H. pylori</i>-positive vs. 2.5 ± 0.2 in <i>H. pylori</i>-negative subjects; p < 0.0001). There was a difference in arterial pCO<sub>2</sub> between <i>H. pylori</i>-positive and <i>H. pylori</i>- negative subjects (43.1 ± 0.3 versus 38.9 ± 0.3 mm Hg; p < 0.0001). <i>Conclusion:</i><i>H. pylori</i> infection has a significant effect on gastric regional CO<sub>2</sub> that is suppressed by application of a proton pump inhibitor.
The "World" of the Enlightenment to Come (Exception, Calculation, Sovereignty)
Authors: Derrida Jacques 
Published: September 2003

AbstractTaking as its point of departure Edmund Husserl's 1935-36 text The Crisis of European Sciences, this essay attempts to develop a new conception of reason by means of a thoroughgoing critique of some ideas often used to support and define it. Because the notion of "enlightenment" has been tied since the time of Kant to a certain coming of age of reason or rationality, the "enlightenment" to come must at once draw upon the resources of this reason and open reason to some of the aporias it has traditionally rejected. Reducible neither to a simple irrationalism nor to a mere mode of calculative thought, such reason must ultimately challenge, it is argued, not only the sovereignty and identity of the (human) subject but the very concepts of sovereignty and identity. Only such a renewed thinking of reason or of what is reasonable, the essay suggests, can help us diagnose, analyze, and help treat some of the aporias posed by a whole host of contemporary issues, from cloning to the erosion of the nation-state to globalization and terrorism. Only in this way can we at once "save the honor of reason" - to use a phrase that runs throughout the essay - and help reorient the reason of politics, of the sciences, and, indeed, of philosophy along the lines of a more fundamental and urgent ethical imperative.
The available‐enthalpy cycle. II: Applications to idealized baroclinic waves
Authors: Marquet Pascal 
Published: September 2003

AbstractThe local available‐enthalpy cycle proposed in Part I of this paper is applied to document energetics of three numerical simulations, representing life cycles of idealized baroclinic waves. An improved temporal numerical scheme defined in Part I is used in this study, together with the Arpège‐IFS model using a T42 triangular truncation. A 45°N and 200 hPa dry unstable jet is constructed with the most unstable mode at zonal wave number 8. Energetic impacts of both horizontal and vertical diffusion schemes are determined separately.The role of ageostrophic winds within the Ekman layer is investigated, leading to an explanation for large observed values for the dissipation terms and to a new formulation of the potential‐energy conversions. The magnitudes of these new conversion terms are compared with those of the usual barotropic and baroclinic conversions. A new version for the available‐enthalpy cycle is proposed. It is suitable for open systems and it includes explicitly the potential‐energy component as a transitional reservoir. Finally, some results from Intensive Observing Period 15 of the Fronts and Atlantic Storm‐Track EXperiment are compared with those from the idealized diabatic experiment. Copyright © 2003 Royal Meteorological Society
Some aspects of the effect of surface friction on flows over mountains
Authors: Peng Melinda S. , Thompson William T. 
Published: September 2003

AbstractThe effect of surface friction on flow over mountains in stratified fluids is investigated using a two‐dimensional version of the Naval Research Laboratory's non‐hydrostatic Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS). Without surface friction, flow over a mountain attains a maximum speed at the surface on the lee slope. With surface friction, the flow speed vanishes at the surface and reaches a maximum near the top of the boundary layer (BL). Corresponding to this wind distribution is a shallow layer of very large vertical wind shear beneath the jet maximum and a weaker but deeper sheared layer elsewhere. This strong shear generates maximum turbulent kinetic energy (TKE) at the jet maximum region. Meanwhile, the buoyancy effect associated with the mountain gravity wave inhibits the production of the TKE above the jet maximum region. The combined effects of shear and buoyancy lead to a very shallow BL on the lee slope. In general, surface friction reduces the amplitude of mountain gravity waves. Comparison of the flow fields with the outline of the BL height indicates that flow characteristics correspond closely to the distribution of the BL height. It is hypothesized that the reduction in mountain‐wave amplitude in the presence of surface friction is due to the reduction in the slope of the BL height as compared to the terrain height. For narrower and/or higher mountains, the BL height exhibits a secondary peak on the lee side that further modifies the wave. Simulations using the BL height as a solid mountain without surface friction confirm that characteristics of flow over the mountain are associated with the distribution of BL height rather than the terrain height field. As the non‐dimensional mountain height increases, the magnitude of the effect of surface friction decreases due to decreasing BL depth on the lee side, with the result that the BL height profile becomes closer to the terrain height field.The effect of surface friction on asymmetric mountains is also investigated. Without surface friction, the pressure drag shows distinctive reduction with a secondary peak on the downstream side, but the effect is less when the secondary peak is on the upstream side. With surface friction, all three mountains have similar pressure drag, corresponding to their similar BL height profiles. Copyright © 2003 Royal Meteorological Society
Evaluating peer mediation outcomes in educational settings: A meta‐analytic review
Authors: Burrell Nancy A. , Zirbel Cindy S. , Allen Mike 
Published: September 2003

AbstractThis investigation summarizes existing research on peer mediation outcomes in school‐based settings. The meta‐analytic review
examines the outcomes associated with incorporating a mediation program to manage school conflict. Results indicate a 93 percent agreement rate and
that 88 percent of the participants were satisfied with the agreements reached. The review answers critics and demonstrates the value of
school‐based mediation programs.
Behavior analysis for approaching the desired trajectory in every trial of learning control
Authors: Takahashi Tohru 
Published: September 2003

AbstractMuch research has been carried out on learning control in which the desired trajectory is completed during repetition of the same operation. Many application classes from linear systems to certain classes of nonlinear systems have been investigated, along with the conditions of their learning stability. However, there seems to be no discussion of the manner of approach of the real trajectory to the desired trajectory in each trial. The reason for investigating this behavior in each trial is that the approach to the desired trajectory may be limited to certain directions, depending on the procedure to which the learning control is applied. In general, as a first step to considering the problem of learning control of the approach of a system with multiple degrees of freedom from a restricted region to the desired target in each trial, a linear time‐invariant learning control system with one input and one output is characterized. In this system, the real trajectory approaches the desired trajectory, given as a function of time, from one of the regions sandwiching the desired target. The obtained results are confirmed by simulation. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(1): 61–71, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10021
Inelastic earthquake response of single‐story asymmetric buildings: an assessment of simplified shear‐beam models
Authors: Stathopoulos K. G. , Anagnostopoulos S. A. 
Published: September 2003

AbstractThe inelastic seismic torsional response of simple structures is examined by means of shear‐beam type models as well as with plastic hinge idealization of one‐story buildings. Using mean values of ductility factors, obtained for groups of ten earthquake motions, as the basic index of post‐elastic response, the following topics are examined with the shear‐beam type model: mass eccentric versus stiffness eccentric systems, effects of different types of motions and effects of double eccentricities. Subsequently, comparisons are made with results obtained using a more realistic, plastic hinge type model of single‐story reinforced concrete frame buildings designed according to a modern Code. The consequences of designing for different levels of accidental eccentricity are also examined for the aforementioned frame buildings. Copyright © 2003 John Wiley & Sons, Ltd.
A response‐spectrum‐based envelope for Mohr's circle
Authors: Menun Charles 
Published: September 2003

AbstractMohr's circle is commonly used to determine the combinations of normal and shear stresses that act in any direction at a location of interest within a structure. During an earthquake, the radius and center of Mohr's circle naturally fluctuate with time. In such cases, an envelope that bounds the time‐varying realizations of Mohr's circle at a given location is desirable to facilitate the identification of critical combinations of normal and shear stresses at that location. In this paper, a response‐spectrum‐based procedure for predicting the envelope that bounds Mohr's circle in a linear‐elastic structure subjected to seismic loads is developed. The accuracy of the proposed envelope is evaluated by comparing it to the results of time‐history analyses performed on a concrete gravity dam using simulated and recorded ground motions. It is found that the proposed envelope has a level of accuracy that is commensurate with its response spectrum bases. The largest observed difference between the simulated and predicted envelopes is less than 10%. Copyright © 2003 John Wiley & Sons, Ltd.
Intracerebroventricular passive immunization with anti‐Aβ antibody in Tg2576
Authors: Chauhan Neelima B. , Siegel George J. 
Published: September 2003

AbstractCurrent Alzheimer's disease (AD) research has established the fact that excessive genesis of Aβ derived from amyloidogenic processing of β‐amyloid (Aβ) precursor protein is fundamental to AD pathogenesis. There has been considerable interest in using immunization strategies for clearing excessive Aβ. Studies in animal models of AD have shown that active immunizations or systemic passive immunizations reduced cerebral plaque load and improved behavioral deficits. However, clinical translation of an active immunization strategy was interrupted because of evidence for meningoencephalitis produced in some patients who received Aβ vaccine. Studies in animal models have shown perimicrovascular hemorrhages and inflammation after sustained systemic immunizations in animals with vascular amyloid. In this light, our data showing the effects of a single intracerebroventricular (ICV) injection of anti‐Aβ in the Alzheimer's Swedish mutant model Tg2576 are intriguing. We have previously demonstrated that a single ICV injection of anti‐Aβ into the third ventricle of 10‐month‐old Tg2576 mice reduced cerebral plaques, reversed Aβ‐induced depletion of presynaptic SNAP‐25, and abolished astroglial activation as seen 1 month post‐injection (Chauhan and Siegel [2002] J. Neurosci. Res. 69:10–23). The present report demonstrates that a single ICV injection of 10 μg anti‐Aβ in 10‐month‐old Tg2576 mice reduced cerebral plaques, with decreased inflammation at this stage as evidenced by a reduced number of interleukin‐1β‐positive microglia surrounding Congophilic plaques. Moreover, at this particular age, no microhemorrhage was discernible, as evidenced by the absence of hemosiderin deposition after a single ICV injection of anti‐Aβ. This is the first report demonstrating absence of microhemorrhage and reduced inflammation after the ICV introduction of anti‐Aβ in Tg2576 mice at 10 months of age. These facts indicate that, although invasive, ICV injection of anti‐Aβ may be a safer method of vaccination in AD, possibly through reducing the vascular exposure to antibody. Further studies are warranted to determine the lasting effects of a single ICV anti‐Aβ injection in animals with and without abundant plaque burden and at older ages. © 2003 Wiley‐Liss, Inc.
Expression of antisense bcl‐2 cDNA abolishes tumorigenicity and enhances chemosensitivity of human malignant glioma cells
Authors: Zhu Cong Ju , Li Yong Biao , Wong Meng Cheong 
Published: September 2003

AbstractBcl‐2 is a key antiapoptotic protein, and it confers survival advantages on many types of tumors by inhibiting apoptotic cell death. Malignant gliomas are the most common primary central nervous system tumors, but the role of bcl‐2 in these tumors has not been defined. We investigated the impact of bcl‐2 on malignant gliomas by suppressing its expression. Antisense human bcl‐2 cDNA was transfected into human malignant glioma cells. The effects of bcl‐2 protein down‐regulation on glioma cell morphology, in vitro tumor growth, and tumorigenicity in nude mice, as well as chemosensitivity to cisplatin, were studied. Expression of antisense bcl‐2 cDNA decreased bcl‐2 protein by more than sixfold. Antisense bcl‐2 stable transfectants (AS‐bcl‐2) showed profound morphological change and markedly retarded cell growth in vitro. Transplantation of AS‐bcl‐2 cells resulted in no tumor formation, whereas backbone plasmid transfectant control formed tumors in each mouse transplanted. Expression of antisense bcl‐2 in glioma cells resulted in significantly increased cytotoxicity of cisplatin. In conclusion, antisense bcl‐2 expression can effectively reduce glioma survival, including retarding in vitro growth, complete loss of tumorigenicity, and significantly enhanced cisplatin cytotoxicity. These results suggest that bcl‐2 plays an important role in glioma malignancy and chemoresistance. Development of strategies targeted at bcl‐2 has the potential to advance treatment for malignant gliomas. © 2003 Wiley‐Liss, Inc.
Suppressive effects of BmK IT2 on nociceptive behavior and c‐Fos expression in spinal cord induced by formalin
Authors: Zhang Xu‐Ying , Bai Zhan‐Tao , Chai Zhi‐Fang , Zhang Jian‐Wei , Liu Ying , Ji Yong‐Hua 
Published: September 2003

AbstractIn this study, the suppressive effects of BmK IT2, a kind of Na+ channel‐specific modulator from the venom of the scorpion Buthus martensi Karsch, on biphasic nociceptive behavior in rats and c‐Fos expression in rat spinal cord induced by formalin were investigated. Fifty microliters of 2.5% formalin were subcutaneously injected into the rat hind paw; 0.1 and 1 μg doses of BmK IT2 were subcutaneously administered into the rat ipsilateral hind paw 1 min before or 10 min after formalin injection individually, and the number of flinches per 5 min was counted. The detection of c‐Fos expression induced by formalin in either the absence or the presence of BmK IT2 was carried out with the ABC method. Biphasic nociceptive behavior in rats was significantly suppressed by pretreatment with BmK IT2. No. of flinches/5 min in the second phase was also decreased by posttreatment with BmK IT2. In addition, c‐Fos expression induced by formalin was significantly inhibited in all laminae of L4–5 spinal cord by pre‐ or posttreatment with BmK IT2. The suppression of BmK IT2 in the first‐ and second‐phase behaviors may be attributed to the anesthesia of the toxin toward nociceptors and primary afferents and its selective modulation of tetrodotoxin‐resistant Na+ currents of dorsal root ganglion neurons, respectively. In addition, the nonparallel suppression of BmK IT2 on flinch behavior and c‐Fos expression induced by formalin may be ascribed to the different activity patterns of afferent fibers and central neurons. © 2003 Wiley‐Liss, Inc.
Uptake of serotonin by adult rat corpus callosum is partially reduced by common antidepressants
Authors: Reyes‐Haro Daniel , García‐Alcocer Guadalupe , Miledi Ricardo , García‐Colunga Jesús 
Published: September 2003

AbstractThe corpus callosum (CC) is the main white matter tract involved in interhemispheric brain communication. We establish that uptake of [3H]5‐hydroxytryptamine (5‐HT) in CC is partially inhibited by some antidepressants. Slices of the adult rat CC had a high‐affinity uptake of 5‐HT. About 80% of this uptake was Na+ dependent, with a Michaelis‐Menten constant, Km, of 420 ± 80 nM and a rate of 5‐HT uptake, Vmax, of 9.5 ± 0.8 pmol/mg protein/min. The 5‐HT uptake was reduced ∼60% at pH 5 compared with that at pH 7. Fluoxetine (Prozac) inhibited only 43% of 5‐HT uptake in a concentration‐dependent manner, with an affinity constant, Ki, of 44.7 ± 10.0 nM. We also studied the effects of other monoamine uptake inhibitors, all at 10 μM, and found that zimelidine, imipramine, and clomipramine inhibited 5‐HT uptake in the CC by ∼30–40%. The fluoxetine‐insensitive 5‐HT uptake was not altered by high concentrations of dopamine plus norepinephrine. The present data show that Na+‐dependent 5‐HT uptake occurs in the CC and optic nerve and that this uptake is partially sensitive to antidepressants and probably mediated by the serotonin transporter, which may be relevant during depression. © 2003 Wiley‐Liss, Inc.
Overexpression of amyloid precursor protein is associated with degeneration, decreased viability, and increased damage caused by neurotoxins (prostaglandins A1 and E2, hydrogen peroxide, and nitric oxide) in differentiated neuroblastoma cells
Authors: Hanson Amy J. , Prasad Judith E. , Nahreini Piruz , Andreatta Cynthia , Kumar Bipin , Yan Xiang‐Dong , Prasad Kedar N. 
Published: September 2003

AbstractInflammatory reactions are considered one of the important etiologic factors in the pathogenesis of Alzheimer's disease (AD). Prostaglandins such as PGE2 and PGA1 and free radicals are some of the agents released during inflammatory reactions, and they are neurotoxic. The mechanisms of their action are not well understood. Increased levels of β‐amyloid fragments (Aβ40 and Aβ42), generated through cleavage of amyloid precursor protein (APP), oxidative stress, and proteasome inhibition, are also associated with neurodegeneration in AD brains. Therefore, we investigated the effect of PGs and oxidative stress on the degeneration and viability of cyclic AMP‐induced differentiated NB cells overexpressing wild‐type APP (NBP2‐PN46) under the control of the CMV promotor in comparison with differentiated vector (NBP2‐PN1) or parent (NBP2) control cells. Results showed that differentiated NBP2‐PN46 cells exhibited enhanced spontaneous degeneration and decreased viability in comparison with differentiated control cells, without changing the level of Aβ40 and Aβ42. PGA1 or PGE2 treatment of differentiated cells caused increased degeneration and reduced viability in all three cell lines. These effects of PGs are not due to alterations in the levels of vector‐derived APP mRNA or human APP holoprotein, secreted levels of Aβ40 and Aβ42, or proteasome activity. H2O2 or SIN‐1 (an NO donor) treatment did not change vector‐derived APP mRNA levels, but H2O2 reduced the level of human APP protein more than SIN‐1. Furthermore, SIN‐1 increased the secreted level of Aβ40, but not of Aβ42, whereas H2O2 had no effect on the level of secreted Aβ fragments. Both H2O2 and SIN‐1 inhibited proteasome activity in the intact cells. The failure of neurotoxins to alter APP mRNA levels could be due to the fact that they do not affect CMV promoter activity. These results suggest that the mechanisms of action of PGs on neurodegeneration are different from those of H2O2 and SIN‐1 and that the mechanisms of neurotoxicity of H2O2 and SIN‐1 are, at least in part, different from each other. © 2003 Wiley‐Liss, Inc.