bluuebunny/crossref_metadata_2025 huggingface dataset:
CORRUPTION, THE GOVERNMENT AND THE PRIVATESECTOR : WHY IT MATTERS AND WHAT CAN BE DONE
Authors: Senior Ian
Published: June 2004

The author proposes a definition of corruption which requires five conditions to be satisfied simultaneously. The definition is applicable to both the state and private sectors. Empirical work shows that corrupt countries receive less inward investment, pay higher interest on borrowings and achieve lower rates of investment overall. Ways of combating corruption are suggested.
SWITZERLAND: GROWTH OF GOVERNMENT, GROWTH OF CENTRALISATION
Authors: Price Victoria Curzon
Published: June 2004

Switzerland has a tradition of decentralised government, decentralised tax setting and direct reference to the voters through referendums. Such mechanisms should give rise to lower taxes, better provision of public goods and higher economic growth. However, these mechanisms have not been effective in the last 30 years at preventing the growth in government spending and centralisation. This is partly because of the consensus in favour of centralisation that exists among institutionalised politicians. The performance of the Swiss economy since 1970 has consequently been dismal. Real per capita post‐tax incomes have been stagnant. There is now an opportunity for the growth of centralisation to be reversed.
MATHEMATICAL FORMALISM IN ECONOMICS: CONSEQUENCES AND ALTERNATIVES1
Authors: Pratten Stephen
Published: June 2004

The blinkered insistence upon formalistic modelling has prevented economics from developing in a way that helps us understand the world in which we live. There are alternative approaches to the study of economics that do not use the formal, often closed‐form, models that contemporary mainstream academic economists rely upon. These provide a more promising avenue for future teaching and research.
MARKET POWER AND THE PHARMACEUTICAL INDUSTRY IN SOUTH AFRICA
Authors: Djolov George G.
Published: June 2004

This paper examines the social cost of the pharmaceutical industry in South Africa. From a regulatory perspective the industry is seen to exhibit monopolylike behaviour resulting in monopoly prices on the supply (manufacturing) side and diminished consumption on the demand (consumer) side. The evidence presented here, which is complementary to that of previous studies, does not support that view. The findings contained here are relevant to the highly contentious subject of access to drugs.
WHO PAYS FOR WHEELCHAIRS?
Authors: Wood Geoffrey E.
Published: June 2004

The issue opened up by the ‘Ryanair Case’ is a wide and important one. Interest groups often press for special treatment at the expense of others. People often agree to give it, because they think the group is deserving and because they have not thought through how the service is to be paid for. By making the charging transparent, as Ryanair has done in this case, people will be forced to think about whether the interest group really is deserving, and if they decide that it is, face up to supporting that view with their own money.
PIOUS LIES: THE JUSTIFICATION OF STATES AND WELFARE STATES
Authors: de Jasay Anthony
Published: June 2004

Institutions, customs, laws are often, and sometimes implausibly, credited with efficiency. They serve a good purpose and if they had not arisen, we would have invented them. The claim is reassuring, though it may be no more than a pious lie. The creation of the state by social contract, and the adoption of supposedly rational customs by primitive peoples, serve as examples. Interpreting the welfare state as a mutual insurance scheme from which all can expect to profit is a classic of the kind.
THEATRE CRITICS AND THEATREGOING
Authors: Senior Ian
Published: June 2004

The paper considers the impact of theatre critics on the West End's main theatres in 2003. The model takes account of the newspapersapos; circulations, the proportion of readers who are theatregoers, the nature of the different reviews and the size of theatres in question. Using a sample of 32 productions with open‐ended runs, the net financial influence of the reviews in 2003 is estimated at £18.7 million, equivalent to 6.3% of the Society of London Theatre's box office takings for the year.
Accession's Democracy Dividend: The Impact of the EU Enlargement upon Democracy in the New Member States of Central and Eastern Europe
Authors: Sadurski Wojciech
Published: June 2004

Abstract:  One of the main factors in ensuring the widespread support for accession to the European Union amongst the various populations of Central and Eastern Europe is the perception that it will serve to entrench and strengthen the process of democratisation after the fall of Communism. The purpose of this article is to examine this claim, that accession will provide a ‘democracy dividend’ in this fashion. To this end, the article begins by examining the political conditionality of the accession process, and the extent to which the process of democratisation can be understood as a result of ‘external’ pressures. It also discusses the extent to which the effectiveness of political conditionality is likely to survive after the accession takes place. The article then moves on to consider the effects of accession upon democracy in the states of the region by looking in detail at three areas that have been particularly important: the role of national parliaments, the new constitutional courts, and the tendency towards decentralisation and regionalism. The article concludes by noting that, although not all of the developments discussed are necessarily good for democracy in the region, the real dividend coming from the accession process lies in the fact that, on a macro‐level, membership in the EU will make the democratic transition in Central and Eastern Europe practically irreversible.
The Cotonou Trade Régime and WTO Law
Authors: Abass Abou
Published: June 2004

Abstract:  The purpose of this paper is to see how the trade régime created by the new Cotonou Partnership Agreement (CPA) signed in 2000 tried to deal with the problem of the incompatibility between Lomé Convention trade preferences and the WTO Law. The first part tries to highlight the incompatibility between the trade preferences and the WTO Law before showing that the CPA has maintained the trade preferences, although on a temporary basis. This has been made possible in part thanks to a waiver exceptionally given by the WTO competent organs, which allows otherwise unlawful preferences for the time being. The second part argues that despite the maintenance of the preferences to a certain extent, the CPA in fact introduces a new era in the EC‐ACP Trade relations characterised by a clear will of harmonising their own legal instruments with the WTO legal régime. This desire to standardise is illustrated by: the integration of WTO principles governing South‐North relations like the Special and Differentiated Treatment principle (SDT), adopting this Organisation's trade concepts, but also by the establishment of a concrete negotiation timetable, in theory to allow the achievement of a full harmonisation by 2020. Thus it has been argued that the Lomé era is being followed by a transition period that should lead to a completely new trade régime, or to many partial régimes, which could render the existence of the ACP countries as a single group less relevant than in previous times.
Towards a European Law of Contracts
Authors: Truilhé‐Marengo Eve
Published: June 2004

Abstract:  European contract law has recently been the subject of increasing attention and intense debate. In addressing this issue, the following contribution departs from traditional analyses of the necessity, feasibility, and opportunity to harmonise national legislation on contractual relations. Instead, the author seeks to demonstrate that, with the objective of promoting the internal market and developing trade within it, EC authorities have long since given birth to a genuine European contract law. Beginning with the analysis of a body of EC directives, this article argues that the genuine nature of this law can be ascertained despite its limits or rather by taking these limits into account. The important rights granted to different contracting parties (consumer‐purchaser, consumer‐tourist, and certain professionals) stand in contrast to the formal incoherence and fragmented character of the legal texts. The article concludes that, in analysing the notion of European contact law, it is necessary to adapt a functional approach rather than a formal one, because the functional approach has dominated European integration and the European law of contracts since its inception.
Gourmet Can Have His Keck and Eat It!
Authors: Kaczorowska Alina
Published: June 2004

Abstract:  The touchstone of the judgment of the Court of Justice in Keck has been the question of how to apply the criteria allowing the exclusion of selling arrangements from the scope of Article 28 EC, in particular in respect of national regulatory rules relating to advertisement. This article examines the evolution of the Court's approach to selling arrangements in the light of the requirements set out in Keck. The judgment in Gourmet has added to the debates as it highlights the issue of the ‘market access’ test as a reference for the assessment of factual discrimination in respect of selling arrangements covered by the Keck exception. The article focuses on the impact of Gourmet on the determination of the outer limits of the scope of application of Article 28 EC, and thus attempts to find a place for Gourmet within the spectrum between the rejection of the judgment in Keck at one end, and the refinement of the requirement relating to ensuring that there is no factual discrimination between imported and domestic products in the application of national rules covered by the Keck exception, at the other.
The Prophylactic Effect of Valproate on Glyceryltrinitrate induced Migraine
Authors: Tvedskov JF , Thomsen LL , Iversen HK , Gibson A , Wiliams P , Olesen J
Published: June 2004

In this study the human glyceryltrinitrate (GTN) model of migraine was for the first time used to test the effect of a prophylactic drug. We chose to test valproate due to its well documented effect as a migraine prophylactic drug. Efficacy of this compound would support the usefulness of the model in prophylactic antimigraine drug development. Twelve patients with migraine without aura were included in a randomized double blind crossover study. Valproate 1000 mg or placebo was given daily, each for a minimum of 13 days. On the last treatment day of each arm a 20 min intravenous infusion of GTN (0.25 μg/kg/min) was given. Headache was registered for 12 h after the infusion and headache intensity was scored on a scale from 0 to 10. Fulfillment of IHS criteria was recorded for 24 h. The middle cerebral arteries were evaluated by transcranial Doppler and the diameter of the superficial temporal and radial arteries were measured with high frequency ultrasound. GTN evoked migraine fulfilling IHS criteria 1.1 in 6 patients after placebo and in 2 patients after valproate ( P = 0.125). Including additionally 3 patients on placebo and 1 patient on valproate who felt they had suffered a migraine attack, but who had as associated symptoms only photophobia or phonophobia, a significant reduction in the number of patients with induced migraine after valproate was seen ( P = 0.031). Median peak headache intensity was 1 (range 0-9) after valproate compared to 4.5 (range 0-8) after placebo ( P = 0.120). Pretreatment with valproate as compared to placebo reduced the velocity in both middle cerebral arteries after GTN (left P = 0.021, right P = 0.031). No effect of valproate was seen in the diameter of the superficial temporal artery ( P = 0.781) or the radial artery ( P = 0.367) before or after GTN. The study indicates that a prophylactic effect of valproate may be demonstrated using the GTN human migraine model. Although, all headache parameters were reduced after valproate compared to placebo, only one parameter was statistically significantly reduced probably because of the small number of patients. The size of the effect was similar to that of valproate in clinical trials. The GTN model may therefore be a valid tool for testing new prophylactic antimigraine drugs.
LY293558, a Novel AMPA/GluR5 Antagonist, is Efficacious and Well-Tolerated in Acute Migraine
Authors: Sang CN , Ramadan NM , Wallihan RG , Chappell AS , Freitag FG , Smith TR , Silberstein SD , Johnson KW , Phebus LA , Bleakman D , Ornstein PL , Arnold B , Tepper SJ , Vandenhende F
Published: June 2004

Glutamatergic hyperactivity is implicated migraine pathogenesis. Also, LY293558, an α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/kainate (KA) receptor antagonist, is effective in preclinical models of migraine. We therefore tested LY293558 in acute migraine. We conducted a randomized, triple-blind, parallel-group, double-dummy, multicentre trial of 1.2 mg/kg intravenous (IV) LY293558, 6 mg subcutaneous (SC) sumatriptan, or placebo in the treatment of acute migraine. The primary efficacy variable was the headache response rate, i.e. headache score improvement from moderate/severe at baseline to mild/none at 2 h. Of 45 enrolled patients, 44 patients (20M:24F; mean age ± SD = 40 ± 9 years) completed the study. Response rates were 69% for LY293558 ( P = 0.017 vs. placebo), 86% for sumatriptan ( P < 0.01 vs. placebo) and 25% for placebo. LY293558 and sumatriptan were superior to placebo ( P < 0.01 for all comparisons) on all other measures of improvement in pain and migraine associated symptoms. Fifteen percent of patients who took LY293558 reported adverse events (AEs) ( n = 2; one mild, one severe). Fifty-three percent of patients who took sumatriptan ( n = 8; seven mild, one moderate) and 31% of those who received placebo reported AEs ( n = 5; four mild, one severe). The efficacy and safety results of LY293558 in this small migraine proof of concept trial, together with supportive preclinical data, provide evidence for a potential role of nonvasoactive AMPA/KA antagonists in treating migraine. Larger trials are needed to further test the hypothesis.
Glycosaminoglycan‐dependent and ‐independent inhibition of neurite outgrowth by agrin
Authors: Baerwald‐De La Torre Kristine , Winzen Uwe , Halfter Willi , Bixby John L.
Published: June 2004

Agrin is a proteoglycan that can inhibit neurite outgrowth from multiple neuronal types when present as a substrate. Agrin's neurite inhibitory activity is confined to the N‐terminal segment of the protein (agrin N150), which contains heparan sulfate (HS) and chondroitin sulfate (CS) side chains. We have examined the activities of various purified recombinant agrin fragments and their glycosaminoglycan (GAG) side chains in neurite outgrowth inhibition. Inhibitory activity was tested using dissociated chick ciliary ganglion neurons or dorsal root ganglion explants growing on laminin or N‐cadherin. Initial experiments demonstrated that agrin N150 lacking GAG chains inhibited neurite outgrowth. Both halves of N150, each containing HS and/or CS side chains, could also inhibit neurite growth. Experiments using agrin fragments in which the GAG acceptor residues were mutated, or using agrin fragments purified from cells deficient in GAG synthesis, demonstrated that inhibition by the N‐terminal portion of N150 requires GAGs, but that inhibition from the C‐terminal part of N150 does not. Thus, the core protein or other types of glycosylation are important for inhibition from the more C‐terminal region. Our results suggest that there are two distinct mechanisms for neurite outgrowth inhibition by agrin, one that is GAG‐dependent and one that is GAG‐independent.
A single amino acid substitution in a proteasome subunit triggers aggregation of ubiquitinated proteins in stressed neuronal cells
Authors: Li Zongmin , Arnaud Lisette , Rockwell Patricia , Figueiredo‐Pereira Maria E.
Published: June 2004

Accumulation of ubiquitinated proteins in inclusions is common to various neurodegenerative disorders such as Parkinson's disease, Alzheimer's disease and amyotrophic lateral sclerosis, although it occurs in selective neurons in each disease. The mechanisms generating such abnormal aggregates and their role in neurodegeneration remain unclear. Inclusions appear in familial and non‐familial cases of neurodegenerative disorders, suggesting that factors other than particular mutations contribute to protein accumulation and aggregation. Proteasome impairment triggered by aging or conditions such as oxidative stress may contribute to protein accumulation and aggregation in neurodegeneration. To test this hypothesis in mouse neuronal cells, we overexpressed a 20S proteasome β5 subunit with an active site mutation. The N‐terminal threonine to alanine substitution resulted in impairment of the chymotrypsin‐like activity, which is a rate‐limiting step in protein degradation by the proteasome. The Thr1Ala mutation was not lethal under homeostatic conditions. However, this single amino acid substitution significantly hypersensitized the cells to oxidative stress, triggering not only the accumulation and aggregation of ubiquitinated proteins, including synuclein, but also cell death. Our results demonstrate that this genetic manipulation of proteasome activity involving a single amino acid substitution causes the formation of protein aggregates in stressed neuronal cells independently of the occurrence of mutations in other cellular proteins. These results support the notion that proteasome disruption may be central to the development of familial as well as sporadic cases of neurodegeneration.
Phospholipid synthesis is decreased in neuronal tissue in a mouse model of Sandhoff disease
Authors: Buccoliero Rosaria , Bodennec Jacques , Van Echten‐Deckert Gerhild , Sandhoff Konrad , Futerman Anthony H.
Published: June 2004

Sandhoff disease is a progressive neurodegenerative disorder caused by mutations in the HEXB gene which encodes for the β‐subunit of β‐hexosaminidase A and B, resulting in ganglioside GM2 accumulation in the brain. We now demonstrate that phospholipid metabolism is altered in both cultured neurons and in brain tissue from a mouse model of Sandhoff disease, the Hexb–/– mouse. Metabolic labelling using [methyl‐14C]choline and l‐[3‐3H]serine demonstrated reduced incorporation of [methyl‐14C]choline into phospholipids in brain tissue but not in liver or spleen. Phospholipid mass was also reduced in brain. The activities of CTP : phosphocholine cytidylyltransferase (CCT) and phosphatidylserine synthase were also reduced in brain tissue from Hexb–/– mice, probably because of post‐translational modification as no changes were observed in levels of enzyme expression. The relevance of these findings to Sandhoff disease in human patients is strengthened by observations made over 30 years ago on autopsy tissue of Tay Sachs and Sandhoff disease patients, in which reduced phospholipid levels were observed. We suggest that changes in phospholipid metabolism are not simply because of loss of neuronal tissue as a result of degeneration but rather may cause degeneration, and we discuss the possible effects that changes in phospholipid metabolism could play in the neuropathophysiology of Sandhoff disease.
Environment‐ and mutation‐dependent aggregation behavior of Alzheimer amyloid β‐protein
Authors: Yamamoto Naoki , Hasegawa Kazuhiro , Matsuzaki Katsumi , Naiki Hironobu , Yanagisawa Katsuhiko
Published: June 2004

The deposition of amyloid β‐protein in the brain is a fundamental process in the development of Alzheimerís disease; however, the mechanism underlying aggregation of amyloid β‐protein remains to be determined. Here, we report that a membrane‐mimicking environment, generated in the presence of detergents or a ganglioside, is sufficient per se for amyloid fibril formation from soluble amyloid β‐protein. Furthermore, hereditary variants of amyloid β‐protein, which are caused by amyloid precursor protein gene mutations, including the Dutch (E693Q), Flemish (A692G) and Arctic (E693G) types, show mutually different aggregation behavior in these environments. Notably, the Arctic‐type amyloid β‐protein, in contrast to the wild‐type and other variant forms, shows a markedly rapid and higher level of amyloid fibril formation in the presence of sodium dodecyl sulfate or GM1 ganglioside. These results suggest that there are favorable local environments for fibrillogenesis of amyloid β‐protein.
Microglia release activators of neuronal proliferation mediated by activation of mitogen‐activated protein kinase, phosphatidylinositol‐3‐kinase/Akt and delta–Notch signalling cascades
Authors: Morgan Sarah C. , Taylor Deanna L. , Pocock Jennifer M.
Published: June 2004

Microglia, the resident macrophage of the brain, can release substances that aid neuronal development, differentiation and survival. We have investigated the effects of non‐activated microglia on the survival of cultured rat cerebellar granule neurones. Microglial‐conditioned medium, collected from primary rat microglial cultures, was used to treat 7‐day‐in‐vitro neurones, and neuronal viability and proliferation was assessed following a further 1 or 7 days in culture. Microglial‐conditioned medium enhanced neuronal survival by up to 50% compared with untreated neurones and this effect was completely abated by pretreatment of the microglia with l‐leucine methyl ester. The expression of the proliferation marker Ki‐67 increased in neuronal cultures treated with microglial‐conditioned medium suggesting enhanced proliferation of precursor neurones. Microglial‐induced neuronal proliferation could be attenuated by specific inhibition of mitogen‐activated protein kinase or phosphatidylinositol‐3‐kinase/Akt signalling pathways, and by selective fractionation and immunodepletion of the microglial‐conditioned medium. Activation of the Notch pathway was enhanced as antibody against the Notch ligand, delta‐1, prevented the microglial‐induced neuronal proliferation. These results show that microglia release stable neurotrophic factors that can promote neuronal precursor cell proliferation.
Differential contribution of plasmalemmal Na+/Ca2+ exchange isoforms to sodium‐dependent calcium influx and NMDA excitotoxicity in depolarized neurons
Authors: Kiedrowski Lech , Czyż Aneta , Baranauskas Gytis , Li Xiao‐Fang , Lytton Jonathan
Published: June 2004

Inhibition of Na+,K+‐ATPase during NMDA applications greatly increased NMDA‐induced excitotoxicity in primary cultures of forebrain neurons (FNs), but not in cerebellar granule cells (CGCs). Because Na+,K+‐ATPase inhibition promotes reversal of plasmalemmal Na+/Ca2+ exchangers, we compared the activities of reversed K+‐independent (NCX) and K+‐dependent (NCKX) Na+/Ca2+ exchangers in these cultures. To this end, we measured gramicidin‐induced and Na+‐dependent elevation in cytosolic [Ca2+] ([Ca2+]c) that represents Ca2+ influx via reversed NCX and NCKX; NCX activity was dissected out by removing external K+. The [Ca2+]c elevations mediated by NCX alone, and NCX plus NCKX combined, were 17 and 6 times more rapid in FNs than in CGCs, respectively. Northern blot analysis showed that FNs preferentially express NCX1 whereas CGCs expressed NCX3. Differences in expression of other isoforms (NCX2, NCKX2, NCKX3 and NCKX4) were less pronounced. We tested whether the NCX or NCKX family of exchangers contributes most to the toxic NMDA‐induced Ca2+ influx in depolarized neurons. We found that in FNs, inhibition of NCX alone was sufficient to significantly limit NMDA excitotoxicity, whereas in CGCs, inhibition of both NCX and NCKX was required. The data suggest that the high activity of NCX isoforms expressed in FNs, possibly NCX1, sensitizes these neurons to NMDA excitotoxicity.
The interaction of Bex and OMP reveals a dimer of OMP with a short half‐life
Authors: Koo Jae Hyung , Gill Stephanie , Pannell Lewis K. , Menco Bert Ph. M. , Margolis Joyce W. , Margolis Frank L.
Published: June 2004

Olfactory marker protein (OMP) participates in the olfactory signal transduction pathway. This is evident from the behavioral and electrophysiological deficits of OMP‐null mice, which can be reversed by intranasal infection of olfactory sensory neurons with an OMP‐expressing adenovirus. Bex, brain expressed X‐linked protein, has been identified as a protein that interacts with OMP. We have now further characterized the interaction of OMP and Bex1/2 by in vitro binding assays and by immuno‐coprecipitation experiments. OMP is a 19 kDa protein but these immunoprecipitation studies have revealed the unexpected presence of a 38 kDa band in addition to the expected 19 kDa band. Furthermore, the 38 kDa form was preferentially co‐immunoprecipitated with Bex from cell extracts. In‐gel tryptic digestion, mass spectrometry, and two‐dimensional gel electrophoresis indicate that the 38 kDa protein behaves as a covalently cross‐linked OMP‐homodimer. The 38 kDa band was also identified in western blots of olfactory epithelium demonstrating its presence in vivo. The stabilities and subcellular localizations of the OMP‐monomer and ‐dimer were studied in transfected cells. These results demonstrated that the OMP‐dimer is much less stable than the monomer, and that while the monomer is present both in the nuclear and cytosolic compartments, the dimer is preferentially located in a Triton X‐100 insoluble cytoskeletal fraction. These novel observations led us to hypothesize that regulation of the level of the rapidly turning‐over OMP‐dimer and its interaction with Bex1/2 is critical for OMP function in sensory transduction.
Drosophila uses two distinct neuropeptide amidating enzymes, dPAL1 and dPAL2
Authors: Han Mei , Park Dongkook , Vanderzalm Pamela J. , Mains Richard E. , Eipper Betty A. , Taghert Paul H.
Published: June 2004

Neuropeptide α‐amidation is a common C‐terminal modification of secretory peptides, frequently required for biological activity. In mammals, amidation is catalyzed by the sequential actions of two enzymes [peptidylglycine‐α‐hydroxylating monooxygenase (PHM) and peptidyl‐α‐hydroxyglycine α‐amidating lyase (PAL)] that are co‐synthesized within a single bifunctional precursor. The Drosophila genome predicts expression of one monofunctional PHM gene and two monofunctional PAL genes. Drosophila PHM encodes an active enzyme that is required for peptide amidation in vivo. Here we initiate studies of the two Drosophila PAL genes. dPAL1 has two predicted transmembrane domains, whereas dPAL2 is predicted to be soluble and secreted. dPAL2 expressed in heterologous cells is secreted readily and co‐localized with hormone. In contrast, dPAL1 is secreted poorly, even when expressed with a cleaved signal replacing the predicted transmembrane domains; the majority of dPAL1 stays in the endoplasmic reticulum. Both proteins display PAL enzymatic activity. Compared to the catalytic core of rat PAL, the two Drosophila lyases have higher Km values, higher pH optima and similarly broad divalent metal ion requirements. Antibodies to dPAL1 and dPAL2 reveal co‐expression in many identified neuroendocrine neurons. Although dPAL1 is broadly expressed, dPAL2 is found in only a limited subset of neurons. dPAL1 expression is highly correlated with the non‐amidated peptide proctolin. Tissue immunostaining demonstrates that dPAL1 is largely localized to the cell soma, whereas dPAL2 is distributed throughout neuronal processes.
Kainate receptor agonists and antagonists mediate tolerance to kainic acid and reduce high‐affinity GTPase activity in young, but not aged, rat hippocampus
Authors: Hesp Blair R. , Wrightson Timothy , Mullaney Ian , Kerr D. Steven
Published: June 2004

Domoic acid acts at both kainic acid (KA) and α‐amino‐3‐hydroxy‐5‐methylisoxazole‐4‐propionate (AMPA)‐sensitive glutamate receptors and induces tolerance against subsequent domoic acid insult in young but not aged rat hippocampus. To determine the receptor specificity of this effect, tolerance induction was examined in hippocampal slices from young and aged rats. Slices were preconditioned by exposure to low‐dose KA to activate kainate receptors, or the AMPA‐receptor selective agonist (S)‐5‐fluorowillardiine (FW), and following washout, tolerance induction was assessed by administration of high concentrations of KA or FW (respectively). FW preconditioning failed to induce tolerance to subsequent FW challenges, while KA‐preconditioned slices were significantly resistant to the effects of high‐dose KA. KA preconditioning failed to induce tolerance in aged CA1. Given the lasting nature of the tolerance effect, we examined G‐protein‐coupled receptor function. A number of ionotropic KA receptor agonists and antagonists significantly reduced constitutive GTPase activity in hippocampal membranes from young but not aged rats. Furthermore, in young CA1, low concentrations of the AMPA/KA blocker GYKI‐52466 also induced tolerance to high‐dose KA. Our findings suggest that tolerance is triggered by a selective reduction in constitutive KA‐sensitive G‐protein activity, and that this potential neuroprotective mechanism is lost with age.
Mapping spatio‐temporal activation of Notch signaling during neurogenesis and gliogenesis in the developing mouse brain
Authors: Tokunaga Akinori , Kohyama Jun , Yoshida Tetsu , Nakao Keiko , Sawamoto Kazunobu , Okano Hideyuki
Published: June 2004

Notch1 plays various important roles including the maintenance of the stem cell state as well as the promotion of glial fates in mammalian CNS development. However, because of the very low amount of the activated form of Notch1 present in vivo, its precise activation pattern has remained unknown. In this study, we mapped the active state of this signaling pathway in situ in the developing mouse brain using a specific antibody that recognizes the processed form of the intracellular domain of Notch1 cleaved by presenilin/γ‐secretase activity. By using this antibody, active state of Notch1 came to be detectable with a higher sensitivity than using conventional antibody against Notch1. We found that activated Notch1 was mainly detected in the nuclei of a subpopulation of radial glial cells, the majority of proliferating precursor cells in the ventricular zone (VZ). However, Notch1 activation was not detected in neuronal precursor cells positive for neuronal basic helix‐loop‐helix proteins or in differentiating neurons in the embryonic forebrain. Interestingly, we found that Notch1 was transiently activated in the astrocytic lineage during perinatal CNS development. Taken together, the present method has enabled us to determine the timing, gradients, and boundaries of the activation of Notch signaling.
In vivo characterization of somatodendritic dopamine release in the substantia nigra of 6‐hydroxydopamine‐lesioned rats
Authors: Sarre Sophie , Yuan Hong , Jonkers Nadine , Van Hemelrijck An , Ebinger Guy , Michotte Yvette
Published: June 2004

We investigated the effect of an injection of 6‐hydroxydopamine (6‐OHDA) into the rat medial forebrain bundle (MFB) on the degeneration and the function of the dopaminergic cell bodies in the substantia nigra (SN) 3 and 5 weeks after lesioning. After injection of 6‐OHDA into the MFB a complete loss of dopamine content was apparent in the striatum 3 weeks after lesioning. In the SN the amount of tyrosine hydroxylase‐immunoreactive dopamine cells decreased gradually, with a near‐complete lesion (> 90%) obtained only after 5 weeks, indicating that neurodegeneration of the nigral cells was still ongoing when total dopamine denervation of the striatum had already been achieved. Baseline dialysate and extracellular dopamine levels in the SN, as determined by in vivo microdialysis, were not altered by the lesion. A combination of compensatory changes of the remaining neurones and dopamine originating from the ventral tegmental area may maintain extracellular dopamine at near‐normal levels. In both intact and lesioned rats, the somatodendritic release was about 60% tetrodotoxin (TTX) dependent. Possibly two pools contribute to the basal dopamine levels in the SN: a fast sodium channel‐dependent portion and a TTX‐insensitive one originating from diffusion of dopamine. Amphetamine‐evoked dopamine release and release after injection of the selective dopamine reuptake blocker GBR 12909 were attenuated after a near‐complete denervation of the SN (5 weeks after lesioning). So, despite a 90% dopamine cell loss in the SN 5 weeks after an MFB lesion, extracellular dopamine levels in the SN are kept at near‐normal levels. However, the response to a pharmacological challenge is severely disrupted.
The synaptophysin/synaptobrevin complex dissociates independently of neuroexocytosis
Authors: Reisinger Clemens , Yelamanchili Sowmya V. , Hinz Britta , Mitter Diana , Becher Anja , Bigalke Hans , Ahnert‐Hilger Gudrun
Published: June 2004

Synaptophysin is one of the most abundant membrane proteins of small synaptic vesicles. In mature nerve terminals it forms a complex with the vesicular membrane protein synaptobrevin, which appears to modulate synaptobrevin's interaction with the plasma membrane‐associated proteins syntaxin and SNAP25 to form the SNARE complex as a prerequisite for membrane fusion. Here we show that synaptobrevin is preferentially cleaved by tetanus toxin while bound to synaptophysin or when existing as a homodimer. The synaptophysin/synaptobrevin complex is, however, not affected when neuronal secretion is blocked by botulinum A toxin which cleaves SNAP25. Excessive stimulation with α‐latrotoxin or Ca2+‐ionophores dissociates the synaptophysin/synaptobrevin complex and increases the interaction of the other SNARE proteins. The stimulation‐induced dissociation of the synaptophysin/synaptobrevin complex is not inhibited by pre‐incubating neurones with botulinum A toxin, but depends on extracellular calcium. However, the synaptophysin/synaptobrevin complex cannot be directly dissociated by calcium alone or in combination with magnesium. The dissociation of synaptobrevin from synaptophysin appears to precede its interaction with the other SNARE proteins and does not depend on the final fusion event. This finding further supports the modulatory role the synaptophysin/synaptobrevin complex may play in mature neurones.
Long‐term regulation of signalling components of adenylyl cyclase and mitogen‐activated protein kinase in the pre‐frontal cortex of human opiate addicts
Authors: Ferrer‐Alcón M. , J. García‐Fuster M. , La Harpe R , García‐Sevilla J. A.
Published: June 2004

Opiate addiction involves the development of chronic adaptive changes in µ‐opioid receptors and associated pathways (e.g. cAMP signalling) which lead to neuronal plasticity in the brain. This study assessed the status of cAMP and mitogen‐activated protein kinase (MAPK) pathways in brains (pre‐frontal cortex) of chronic opiate addicts. In these subjects (n = 24), the immunodensities of adenylyl cyclase‐I, PKA Cα, total and phosphorylated CREB were not different from those in sex‐, age‐ and PMD‐matched controls. Moreover, the ratio pCREB/tCREB was similar in opiate addicts (0.74) and controls (0.76), further indicating that opiate addiction in humans is not associated with an upregulation of several key components of cAMP signalling in the pre‐frontal cortex. In contrast, the components of MAPK cascade (Ras/c‐Raf‐1/MEK/ERK) were decreased in the same brains. Notably, pronounced downregulations of phosphorylated MEK (85%) and ERK1/2 (pERK1: 81%; pERK2: 80%) were quantitated in brains of opiate addicts. Chronic morphine treatment in rats (10–100 mg/kg for 5 days) was also associated with decreases of pERK1/2 (59–68%) in the cortex. In SH‐SY5Y cells, morphine also stimulated the activity of pERK1/2 (2.5‐fold) and the MEK inhibitor PD98059 blocked this effect (90%). The abnormalities of MAPK signalling might have important consequences in the long term development of various forms of neural plasticity associated with opiate addiction in humans.
Differential effects of Rho GTPases on axonal and dendritic development in hippocampal neurones
Authors: Ahnert‐Hilger G. , Höltje M. , Große G. , Pickert G. , Mucke C. , Nixdorf‐Bergweiler B. , Boquet P. , Hofmann F. , Just I.
Published: June 2004

Formation of neurites and their differentiation into axons and dendrites requires precisely controlled changes in the cytoskeleton. While small GTPases of the Rho family appear to be involved in this regulation, it is still unclear how Rho function affects axonal and dendritic growth during development. Using hippocampal neurones at defined states of differentiation, we have dissected the function of RhoA in axonal and dendritic growth. Expression of a dominant negative RhoA variant inhibited axonal growth, whereas dendritic growth was promoted. The opposite phenotype was observed when a constitutively active RhoA variant was expressed. Inactivation of Rho by C3‐catalysed ADP‐ribosylation using C3 isoforms (Clostridium limosum, C3lim or Staphylococcus aureus, C3stau2), diminished axonal branching. By contrast, extracellularly applied nanomolar concentrations of C3 from C. botulinum (C3bot) or enzymatically dead C3bot significantly increased axon growth and axon branching. Taken together, axonal development requires activation of RhoA, whereas dendritic development benefits from its inactivation. However, extracellular application of enzymatically active or dead C3bot exclusively promotes axonal growth and branching suggesting a novel neurotrophic function of C3 that is independent from its enzymatic activity.
Different activation of NF‐κB by stimulation of dopamine D2L and D2S receptors through calcineurin activation
Authors: Takeuchi Yusuke , Fukunaga Kohji
Published: June 2004

Dopamine D2 receptor (D2R) has known to activate Ca2+/calmodulin‐dependent protein phosphatase, calcineurin by increasing in the intracellular Ca2+. We previously showed that D2LR (long isoform) and D2SR (short isoform) enhanced SRE and NF‐κB, and conversely suppressed CRE transcriptional activities in NG108‐15 cells stably expressed with these receptors (NGD2LR and NGD2SR). In this study, to investigate whether activation of calcineurin is involved in the transcriptional regulations through D2R, we evaluated effect of cyclosporin A, a selective calcineurin inhibitor, on them in NGD2LR and NGD2SR cells using luciferase reporter gene assay. We first confirmed that D2LR activates calcineurin in NG108‐15 cells by measurement of dephosphorylation of dopamine‐ and cyclic AMP‐regulated phosphoprotein Mr 32 000 (DARPP‐32) at threonin 34 by immunoblot analysis with its phospho‐specific antibody. Cyclosporin A treatment showed no change in suppression of forskolin‐induced CRE activation or activation of SRE but significantly attenuated NF‐κB activation by D2LR stimulation in NGD2LR cells. Interestingly, D2SR‐induced NF‐κB activation, which was weaker than that by D2LR stimulation, was not affected by cyclosporin A treatment in NGD2SR cells. Furthermore, D2SR stimulation did not cause dephosphorylation of DARPP‐32 at threonin 34. Taken together, D2SR and D2LR may employ different signaling pathway on intracellular Ca2+ mobilization, thereby showing different NF‐κB activation in the calcineurin‐dependent manner.
Oral administration of Crataegus flavonoids protects against ischemia/reperfusion brain damage in gerbils
Authors: Zhang De‐Liang , Zhang Yue‐Ting , Yin Jun‐Jie , Zhao Bao‐Lu
Published: June 2004

Stroke is the third leading cause of death as dementia is a main symptom of Alzheimer's disease. One of the important mechanisms in the pathogeny of stroke is free radical production during the reperfusion period, therefore the effects of a type of natural antioxidant, i.e. Crataegus flavonoids (CF), on brain ischemic insults were investigated in Mongolian gerbil stroke model. Results showed that pretreatment of the animals with CF decreased reactive oxygen species (ROS) production, thiobarbituric acid reactive substances content, and nitrite/nitrate concentration in brain homogenate, increased the brain homogenate‐associated antioxidant level in a dose‐dependent manner. CF pretreatment increased the amount of biologically available NO by scavenging of superoxide anion produced during reperfusion. At same time, in the process of ischemia/reperfusion brain damage, the content of nitrite/nitrate (the end product of NO) increased, and of NO detected by ESR decreased. Oral pretreatment with CF decreased the nitrite/nitrate content in the brain homogenate and increased the biologically available NO concentration in a dose‐dependent manner. The increasing effect of antioxidant on NO might be due to its scavenging effect on superoxide anion, which could react with NO into peroxynitrite. iNOS was implied in delayed neuron death after brain ischemic damage and it was found that pretreatment with CF could decrease the protein level of tumor necrosis factor (TNF)‐α and nuclear factor‐kappa B (NF‐κB), and increase the mRNA level of NOS estimated by western blotting and RT‐PCR. More neurons survived and fewer cells suffered apoptosis in the hippocampal CA1 region of CF treated animal brain. These results suggest that oral administration of this antioxidant increases the antioxidant level in the brain and protects the brain against delayed cell death caused by ischemia/reperfusion injury.
The brefeldin A‐inhibited GDP/GTP exchange factor 2, a protein involved in vesicular trafficking, interacts with the β subunits of the GABAA receptors
Authors: Charych Erik I. , Yu Wendou , Miralles Celia P. , Serwanski David R. , Li Xuejing , Rubio Maria , De Blas Angel L.
Published: June 2004

We have found that the brefeldin A‐inhibited GDP/GTP exchange factor 2 (BIG2) interacts with the β subunits of the γ‐aminobutyric acid type‐A receptor (GABAAR). BIG2 is a Sec7 domain‐containing guanine nucleotide exchange factor known to be involved in vesicular and protein trafficking. The interaction between the 110 amino acid C‐terminal fragment of BIG2 and the large intracellular loop of the GABAAR β subunits was revealed with a yeast two‐hybrid assay. The native BIG2 and GABAARs interact in the brain since both coprecipitated from detergent extracts with either anti‐GABAAR or anti‐BIG2 antibodies. In transfected human embryonic kidney cell line 293 cells, BIG2 promotes the exit of GABAARs from endoplasmic reticulum. Double label immunofluorescence of cultured hippocampal neurons and electron microscopy immunocytochemistry of rat brain tissue show that BIG2 concentrates in the trans‐Golgi network. BIG2 is also present in vesicle‐like structures in the dendritic cytoplasm, sometimes colocalizing with GABAARs. BIG2 is present in both inhibitory GABAergic synapses that contain GABAARs and in asymmetric excitatory synapses. The results are consistent with the hypotheses that the interaction of BIG2 with the GABAAR β subunits plays a role in the exocytosis and trafficking of assembled GABAAR to the cell surface.
Striatal GDNF administration increases tyrosine hydroxylase phosphorylation in the rat striatum and substantia nigra
Authors: Salvatore Michael F. , Zhang Jin‐Lu , Large Delia M. , Wilson Patsy E. , Gash Clelland R. , Thomas Theresa Currier , Haycock John W. , Bing Guoying , Stanford John A. , Gash Don M. , Gerhardt Greg A.
Published: June 2004

Glial cell line‐derived neurotrophic factor (GDNF) improves motor dysfunction associated with aging in rats and non‐human primates, in animal models of Parkinson's disease, and may improve motoric function in patients with advanced Parkinson's disease. These improvements are associated with increased dopamine function in the nigrostriatal system, but the molecular events associated with this increase are unknown. In these studies, 100 µg of GDNF was injected into the striatum of normal aged (24‐month‐old) male Fischer 344 rats. The protein levels and phosphorylation of TH, ERK1/2, and related proteins were determined by blot‐immunolabeling of striatum and substantia nigra harvested 30 days after injection. In GDNF‐treated rats, TH phosphorylation at Ser31 increased ∼40% in striatum and ∼250% in the substantia nigra. In the substantia nigra, there was a significant increase in ERK1 phosphorylation. In striatum, there was a significant increase in ERK2 phosphorylation. Microdialysis studies in striatum showed that both amphetamine‐ and potassium‐evoked dopamine release in GDNF recipients were significantly increased. These data show that GDNF‐induced increases in dopamine function are associated with a sustained increase in TH phosphorylation at Ser31, which is greatest in the substantia nigra and maintained for at least one month following a single striatal administration of GDNF. These findings, taken from the nigrostriatal system of normal aged rats, may help explain the long lasting effects of GDNF on dopamine function and prior studies supporting that a major effect of GDNF involves its effects on dopamine storage and somatodendritic release of dopamine in the substantia nigra.
The origins of Euroscepticism in German‐speaking Switzerland
Authors: THEILER TOBIAS
Published: June 2004

Abstract.  This article examines why the electorate in German‐speaking Switzerland has consistently opposed joining the European Union. It first shows that the region scores highly on a range of general correlates of negative attitudes towards European integration. However, this is compounded by more idiosyncratic factors, above all by the German‐speaking Swiss’ peculiar political and cultural position. On the one hand, as Swiss they belong to a state that lacks a single national culture, is defined in civic and institutional rather than cultural terms, and therefore appears more vulnerable in the face of the European Union's own civic and institutional ambitions. On the other hand, as Swiss‐Germans, they belong to a cultural and linguistic region whose cultural boundaries are relatively fragile and lack institutional backup and articulation. Caught in this identitive double bind, the Swiss‐German electorate has developed an underlying sense of vulnerability and a desire to limit exposure to the outside world.
Parties, promiscuity and politicisation: Business‐political networks in Poland
Authors: McMENAMIN IAIN
Published: June 2004

Abstract.  Research on post‐communist political economy has begun to focus on the interface between business and politics. It is widely agreed that informal networks rather than business associations dominate this interface, but there has been very little systematic research in this area. The literature tends to assume that a politicised economy entails business‐political networks that are structured by parties. Theoretically, this article distinguishes politicisation from party politicisation and argues that the two are unlikely to be found together in a post‐communist context. Empirically, elite survey data and qualitative interviews are used to explore networks of businesspeople and politicians in Poland. Substantial evidence is found against the popular idea that Polish politicians have business clienteles clearly separated from each other according to party loyalties. Instead, it is argued that these politicians and businesspeople are promiscuous. Since there seems to be little that is unusual about the Polish case, this conclusion has theoretical, methodological, substantive and policy implications for other post‐communist countries.