bluuebunny/crossref_metadata_2025_split huggingface dataset:
Japan and Africa after the Cold War
Authors: Morikawa Jun 
Published: February 2006

AbstractThe purposes of this article are twofold. The first is to discuss the factors that make inquiry into Japan's African diplomacy difficult, in connection with the elaborate publicity campaign run by the Ministry of Foreign Affairs (MOFA), focusing on the Tokyo International Conference on African Development (TICAD). The second is to examine the current status of, issues in and future of Japan's African diplomacy in the post-Cold War, post-apartheid era and the meaningful participation of Japanese citizens in formulating and implementing foreign policy in reference to the regional power of South Africa. The article concludes that there is a significant gap between words and action in Japan's African diplomacy that has led to a loss of credibility and that attempts by MOFA to recoup the loss using aid or rhetoric are likely to rather result in heightened distrust on the African side and that securing trust will require structural reform and building foreign policy that is based on the wishes and interests of the people and subject it to democratic control.
No effects of l-dopa and bromocriptine on psychophysiological parameters of human selective attention
Authors: Oranje B. , Gispen-de Wied C. C. , Westenberg H. G. M. , Kemner C. , Verbaten M. N. , Kahn R. S. 
Published: February 2006

Patients with schizophrenia exhibit diverse cognitive deficits, one of which is a loss of the ability to focus attention. According to the revised dopamine hypothesis of schizophrenia both an increased mesolimbic and a decreased prefrontal dopaminergic activity is suggested to be involved in schizophrenia. The current study was designed to explore the relationship between dopamine and two psychophysiological parameters of selective attention, i.e. P300 amplitude and processing negativity (PN) in healthy volunteers. In two separate experiments, with a double-blind, balanced and placebo-controlled crossover design, 18 healthy male volunteers were orally administered either 300mg l-dopa (precursor of dopamine) or placebo (experiment I), or 1.25mg bromocriptine (D2 agonist) or placebo (experiment II). Following this treatment they were tested in an auditory, dichotic selective attention paradigm. An increase in P300 amplitude was found following deviant stimuli when compared to standard stimuli and following attended stimuli when compared to unattended stimuli, regardless of treatment. Similarly, PN was found regardless of treatment. Neither l-dopa nor bromocriptine affected task performance or the amplitudes of PN or P300. In the present study neither l-dopa nor bromocriptine affected PN, P300 amplitude or task performance in healthy controls, phenomena which are usually found to be disrupted in schizophrenia. This indicates that P300 amplitude and PN are neither affected by a global (l-dopa) increased dopaminergic activity, nor by a more selectively towards striatal areas targeted (bromocriptine) increase in dopaminergic activity.
Wegener autoantigen induces maturation of dendritic cells and licenses them for Th1 priming via the protease-activated receptor-2 pathway
Authors: Csernok Elena , Ai MaiXing , Gross Wolfgang L. , Wicklein Daniel , Petersen Arnd , Lindner Buko , Lamprecht Peter , Holle Julia U. , Hellmich Bernhard 
Published: February 2006

AbstractAutoantibodies to proteinase 3 (PR3) are involved in the pathogenesis of autoimmune-mediated vasculitis in Wegener granulomatosis (WG). To address the question how the autoantigen PR3 becomes a target of adaptive immunity, we investigated the effect of PR3 on immature dendritic cells (iDCs) in patients with WG, healthy blood donors, and patients with Crohn disease (CD), another granulomatous disease. PR3 induces phenotypic and functional maturation of a fraction of blood monocyte-derived iDCs. PR3-treated DCs express high levels of CD83, a DC-restricted marker of maturation, CD80 and CD86, and HLA-DR. Furthermore, the DCs become fully competent antigen-presenting cells and can induce stimulation of PR3-specific CD4+ T cells, which produce IFN-γ. PR3-maturated DCs derived from WG patients induce a higher IFN-γ response of PR3-specific CD4+ T cells compared with patients with CD and healthy controls. The maturation of DCs mediated through PR3 was inhibited by a serine protease inhibitor, by antibodies directed against the protease-activated receptor-2 (PAR-2), and by inhibition of phospholipase C, suggesting that the interactions of PR3 with PAR-2 are involved in the induction of DC maturation. Wegener autoantigen interacts with a “gateway” receptor (PAR-2) on iDCs in vitro triggering their maturation and licenses them for a T helper 1 (Th1)–type response potentially favoring granuloma formation in WG.
Differential effects of experimental and cold-induced hyperthyroidism on factors inducing rat liver oxidative damage
Authors: Venditti P. , Pamplona R. , Ayala V. , De Rosa R. , Caldarone G. , Di Meo S. 
Published: February 2006

SUMMARY
Thyroid hormone-induced increase in metabolic rates is often associated with increased oxidative stress. The aim of the present study was to investigate the contribution of iodothyronines to liver oxidative stress in the functional hyperthyroidism elicited by cold, using as models cold-exposed and 3,5,3′-triiodothyronine (T3)- or thyroxine(T4)-treated rats. The hyperthyroid state was always associated with increases in both oxidative capacity and oxidative damage of the tissue. The most extensive damage to lipids and proteins was found in T3-treated and cold-exposed rats, respectively. Increase in oxygen reactive species released by mitochondria and microsomes was found to contribute to tissue oxidative damage, whereas the determination of single antioxidants did not provide information about the possible contribution of a reduced effectiveness of the antioxidant defence system. Indeed, liver oxidative damage in hyperthyroid rats was scarcely related to levels of the liposoluble antioxidants and activities of antioxidant enzymes. Conversely,other biochemical changes, such as the degree of fatty acid unsaturation and hemoprotein content, appeared to predispose hepatic tissue to oxidative damage associated with oxidative challenge elicited by hyperthyroid state.
As a whole, our results confirm the idea that T3 plays a key role in metabolic changes and oxidative damage found in cold liver. However,only data concerning changes in glutathione peroxidase activity and mitochondrial protein content favour the idea that dissimilarities in effects of cold exposure and T3 treatment could depend on differences in serum levels of T4.
The accumulation of methylamine counteracting solutes in elasmobranchs with differing levels of urea: a comparison of marine and freshwater species
Authors: Treberg Jason R. , Speers-Roesch Ben , Piermarini Peter M. , Ip Yuen K. , Ballantyne James S. , Driedzic William R. 
Published: February 2006

SUMMARYWe compared levels of the major organic osmolytes in the muscle of elasmobranchs, including the methylamines trimethylamine oxide (TMAO), betaine and sarcosine as well as the β-amino acids taurine and β-alanine,and the activities of enzymes of methylamine synthesis (betaine and TMAO) in species with a wide range of urea contents. Four marine, a euryhaline in freshwater (Dasyatis sabina), and two freshwater species, one that accumulates urea (Himantura signifer) and one that does not(Potamotrygon motoro), were analyzed. Urea contents in muscle ranged from 229–352 μmol g–1 in marine species to 2.0μmol g–1 in P. motoro. Marine elasmobranchs preferentially accumulate methylamines, possibly to counteract urea effects on macromolecules, whereas the freshwater species with lower urea levels accumulate the β-amino acid taurine as the major non-urea osmolyte. A strong correlation (r2=0.84, P&lt;0.001) with a slope of 0.40 was found between muscle urea content and the combined total methylamines plus total β-amino acids, supporting the hypothesis that`non-urea' osmolytes are specifically maintained at an approximately 2:1 ratio with urea in the muscle of elasmobranchs. All species examined had measurable synthetic capacity for betaine in the liver but only one species had detectable TMAO synthetic capacity. We propose a phylogenetic explanation for the distribution of TMAO synthesis in elasmobranchs and suggest that activation of liver betaine aldehyde dehydrogenase, relative to choline dehydrogenase, coincides with betaine accumulation in elasmobranchs. The latter relationship may be important in maintaining methylamine levels during periods of low dietary TMAO intake for species lacking TMAO synthesis.
Pseudodiarrhoea in zebra mussels Dreissena polymorpha (Pallas)exposed to microcystins
Authors: Juhel Guillaume , Davenport John , O'Halloran John , Culloty Sarah , Ramsay Ruth , James Kevin , Furey Ambrose , Allis Orla 
Published: February 2006

SUMMARY
Microcystins are produced by bloom-forming cyanobacteria and pose significant health and ecological problems. In this study we show that zebra mussels respond differently to different strains of Microcystis aeruginosa, and that a highly toxic strain causes zebra mussels to produce large quantities of mucous pseudofaeces, `pseudodiarrhoea', that are periodically expelled hydraulically through the pedal gape by shell valve adductions rather than by the normal ciliary tracts. Analysis of the pseudofaecal ejecta showed that the proportion of Microcystis aeruginosa relative to Asterionella formosa was high in the pseudofaeces and even higher in the `pseudodiarrhoea' when a mixed diet was given to the mussels. This confirms that very toxic Microcystis aeruginosa were preferentially being rejected by comparison with the non-toxic diatom in the pseudofaeces and even more so in the`pseudodiarrhoea'. Such selective rejection was not observed with low or non-toxic strains and would therefore tend to enhance the presence of toxic Microcystis aeruginosa in mixed Microcystis aeruginosacyanobacterial blooms, as well as transferring toxins from the water column to the benthos.
The observed acute irritant response to the toxin represents the first demonstration of an adverse sublethal effect of microcystins on invertebrate ecophysiology. Our results also suggest that it could be a specific response to microcystin-LF, a little studied toxin variant.
Visual regulation of ground speed and headwind compensation in freely flying honey bees (Apis mellifera L.)
Authors: Barron Andrew , Srinivasan Mandyam V. 
Published: February 2006

SUMMARY
There is now increasing evidence that honey bees regulate their ground speed in flight by holding constant the speed at which the image of the environment moves across the eye (optic flow). We have investigated the extent to which ground speed is affected by headwinds. Honey bees were trained to enter a tunnel to forage at a sucrose feeder placed at its far end. Ground speeds in the tunnel were recorded while systematically varying the visual texture of the tunnel, and the strength of headwinds experienced by the flying bees. We found that in a flight tunnel bees used visual cues to maintain their ground speed, and adjusted their air speed to maintain a constant rate of optic flow, even against headwinds which were, at their strongest, 50% of a bee's maximum recorded forward velocity. Manipulation of the visual texture revealed that headwind is compensated almost fully even when the optic flow cues are very sparse and subtle, demonstrating the robustness of this visual flight control system. We discuss these findings in the context of field observations of flying bees.
Contractile recovery from acidosis in toad ventricle is independent of intracellular pH and relies upon Ca2+ influx
Authors: Salas Margarita A. , Vila-Petroff Martín G. , Venosa Roque A. , Mattiazzi Alicia 
Published: February 2006

SUMMARYHypercapnic acidosis produces a negative inotropic effect on myocardial contractility followed by a partial recovery that occurs in spite of the persistent extracellular acidosis. The underlying mechanisms of this recovery are far from understood, especially in those species in which excitation–contraction coupling differs from that of the mammalian heart. The main goal of the present experiments was to obtain a better understanding of these mechanisms in the toad heart. Hypercapnic acidosis,induced by switching from a bicarbonate-buffered solution equilibrated with 5%CO2 to the same solution equilibrated with 12% CO2,evoked a decrease in contractility followed by a recovery that reached values higher than controls after 30 min of continued acidosis. This contractile pattern was associated with an initial decrease in intracellular pH(pHi) that recovered to control values in spite of the persistent extracellular acidosis. Blockade of the Na+/H+ exchanger(NHE) with cariporide (5 μmol l–1) produced a complete inhibition of pHi restitution, without affecting the mechanical recovery. Hypercapnic acidosis also produced a gradual increase of diastolic and peak Ca2+i transient values, which occurred immediately after the acidosis was settled and persisted during the mechanical recovery phase. Inhibition of Ca2+ influx through the reverse mode of the Na+/Ca2+ exchanger (NCX) by KB-R (1 μmol l–1 for myocytes and 20 μmol l–1 for ventricular strips), or of L-type Ca2+ channels by nifedipine (0.5μmol l–1), completely abolished the mechanical recovery. Acidosis also produced an increase in the action potential duration. This prolongation persisted throughout the acidosis period. Our results show that in toad ventricular myocardium, acidosis produces a decrease in contractility,due to a decrease in Ca2+ myofilament responsiveness, followed by a contractile recovery, which is independent of pHi recovery and relies on an increase in the influx of Ca2+. The results further indicate that both the reverse mode NCX and the L-type Ca2+channels, appear to be involved in the increase in intracellular Ca2+ concentration that mediates the contractile recovery from acidosis.
Imaging Protein‐Protein Interactions by Fluorescence Resonance Energy Transfer (FRET) Microscopy
Authors: Wouters Fred S. , Bastiaens Philippe I.H. 
Published: February 2006

AbstractDetection of specific protein‐protein interactions has long been restricted to bulk biochemical methods such as immunoprecipitation and immunoblotting. Even more sensitive methods using general immunofluorescence are limited, and it is difficult to infer protein‐protein interactions from the results of these tests. Fluoresence Resonance Energy Transfer (FRET) is a photophysical process that can be exploited to obtain highly sensitive information about such interactions. It can sense the presence of acceptor fluorophores in the vicinity of a donor fluorophore within a separation distance that is the size of a single protein molecule. This unit details FRET microscopy based on release of quenched donor fluorescence after acceptor photobleaching, microinjection of reagents into the nucleus or cytosol, and labeling of antibodies for these procedures.
Monitoring Protein‐Protein Interactions in Living Cells by Bioluminescence Resonance Energy Transfer (BRET)
Authors: Hamdan Fadi F. , Percherancier Yann , Breton Billy , Bouvier Michel 
Published: February 2006

AbstractBioluminescence resonance energy transfer (BRET) allows monitoring of protein‐protein interactions in real time in living cells. One candidate interacting protein is fused to a luminescent energy donor, such asRenillaluciferase, and the other to a fluorescent energy acceptor, such the green fluorescent protein (GFP), and the two are then coexpressed in the same cells. If the two proteins interact, their close proximity allows nonradiative energy transfer (BRET) between the luciferase and the GFP. BRET does not occur if the two proteins are separated by more than 100 Å, making the technique ideal for monitoring protein‐protein interactions in biological systems. This unit describes the use of BRET to study constitutive and agonist‐promoted interactions among signaling molecules, as illustrated by the homodimerization of the CXCR4 receptor and the recruitment of β‐arrestin2 to agonist‐activated G‐protein‐coupled receptors. This noninvasive and homogeneous assay provides a robust and sensitive proteomic platform with applications for basic science research and drug discovery.
Assessment of Cochlear Function in Mice: Distortion‐Product Otoacoustic Emissions
Authors: Martin Glen K. , Stagner Barden B. , Lonsbury‐Martin Brenda L. 
Published: February 2006

AbstractDistortion‐product otoacoustic emissions (DPOAEs) can be measured in the ear canal following the presentation of two tones. These emissions are generated by the outer hair cells (OHCs) of the inner ear and they are reduced or absent when the OHCs are damaged by, for example, exposure to excessive noise or ototoxic drugs. Consequently, DPOAEs provide a powerful and noninvasive means to assess the robustness of OHC function. A detailed method is described for measuring DPOAEs to assess cochlear function in mice. Recommendations are given for the required equipment and instructions are presented for setting up a DPOAE system. Also, a protocol is outlined for measuring DPOAEs in mice and troubleshooting tips are provided. Examples of data analysis procedures following noise exposure in mice are included, as well. These methods are not only applicable to mice, but can be performed using essentially all small laboratory animals.
Uses of Forward and Reverse Genetics in Mice to Study Gene Function
Authors: Argmann Carmen A. , Dierich Andree , Auwerx Johan 
Published: February 2006

AbstractAs the focus of human genetics shifts from Mendelian traits to complex diseases, a sophisticated genetic tool kit—with space for genetics (classical, molecular, statistical, and quantitative), metabolics, proteomics, bioinformatics, and mathematics—is required to elucidate their multifactorial traits and regulatory processes. Importantly, mouse resources optimized to study the actions of isolated genetic loci on a fixed background are insufficient on their own for studying intact polygenic networks and genetic interactions, and researchers must work in the context of experimental model systems that optimally mimic the genetic structure of human populations. The success of such phenogenomic approaches depend on the efficacy by which specific mutations (gene targeting) and variability (recombinant inbreeding) can be introduced into the mouse genome, and on the optimization of phenotyping analyses of the mutant mouse lines. This unit describes the basic genetic approaches used to in the study of mouse model systems.
Evaluation of Energy Homeostasis
Authors: Argmann Carmen A. , Champy Marie‐France , Auwerx Johan 
Published: February 2006

AbstractBody mass and composition reflect the combined effects of three processes: energy intake, energy partitioning (storage), and energy expenditure. Energy is released from food as it is combusted to carbon dioxide and water, and is expended as heat and work within a cell. The energy stores, mainly in adipose tissue, represent the net balance between intake and expenditure. The methods outlined in this unit evaluate these three processes by measuring food intake and lipid absorption, body fat composition, and energy expenditure. Evaluation of food intake and fat mass is a useful first‐line phenotyping test indicating altered energy homeostasis. Evaluation of energy expenditure in this unit addresses obligatory basal energy expenditure (for performance of cellular and organ functions), as measured by indirect calorimetry. The combined results of these tests provide indications of the metabolic defects in a mouse model and help to identify molecular targets that cause these abnormalities.
Overview of Model Systems for the Analysis of Human Disease
Authors: Lind Joanne , Semsarian Christopher 
Published: February 2006

AbstractThe development of animal models of human disease has been crucial in elucidating normal organ biology and pathogenic mechanisms leading to disease states, and in the development of new therapeutic strategies to modify disease. This unit provides an overview of various animal models used in the study of human disease and the factors that need to be considered when selecting a suitable animal model appropriate for the disease under investigation.
Thermophoresis of an aerosol sphere perpendicular to two plane walls
Authors: Keh Huan J. , Chang Yu C. 
Published: February 2006

AbstractThe problem of the thermophoretic motion of a spherical particle in a gaseous medium situated at an arbitrary position between two infinite parallel plane walls is studied theoretically in the quasisteady limit of negligible Peclet and Reynolds numbers. The imposed temperature gradient is uniform and perpendicular to the plane walls. The Knudsen number is assumed to be small so that the fluid flow is described by a continuum model with a temperature jump, a thermal slip, and a frictional slip at the particle surface. The presence of the confining walls causes two basic effects on the particle velocity: first, the local temperature gradient on the particle surface is altered by the walls, thereby speeding up or slowing down the particle; second, the walls enhance the viscous retardation of the moving particle. A boundary collocation method is used to solve the thermal and hydrodynamic governing equations of the system. Numerical results for the thermophoretic velocity of the particle relative to that under identical conditions in an unbounded gaseous medium are presented for various cases. The collocation results agree well with the available approximate analytical solutions obtained by using a method of reflections. The presence of the walls can reduce or enhance the particle velocity, depending upon the relative thermal conductivity and surface properties of the particle as well as the relative particle‐wall separation distances. The boundary effect on thermophoresis of a particle normal to two plane walls is found to be quite significant and generally stronger than that parallel to the confining walls. © 2006 American Institute of Chemical Engineers AIChE J, 2006
Multitasking by Multivalent Circular DNA Aptamers
Authors: Di Giusto Daniel A. , Knox Sarah M. , Lai Yuching , Tyrelle Gregory D. , Aung May T. , King Garry C. 
Published: February 2006

AbstractNucleic acid aptamers are finding increasing applications in biology, especially as therapeutic candidates and diagnostic components. An important characteristic in meeting the needs of these applications is improved stability in physiological fluids, which is most often accomplished with chemical modification or unnatural nucleotides. In an alternative approach we have specified the design of a multivalent circular DNA aptamer topology that encompasses a number of properties relevant to nucleic acid therapeutic candidates, especially the ability to multitask by combining different activities together within a modular structure. Improved stability in blood products, greater conformational stability, antidoting by complementary circular antiaptamers, heterovalency, transcription factor decoy activity and minimal unintended effects upon the cellular innate immune response are desirable properties that are described here. Multitasking by circular DNA aptamers could similarly find applications in diagnostics and biomaterials, where the combination of interchangeable modules might generate new functions, such as anticoagulation coupled with reversible cell capture as, described here. These results provide a platform for further exploration of multivalent circular aptamer properties, especially in novel combinations of nucleic acid therapeutic modes.