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Social capital is considered important for resilience across social levels, including communities, yet insights are scattered across disciplines. This meta-synthesis of 187 studies examines conceptual and empirical understandings of how social capital relates to resilience, identifying implications for community resilience and climate change practice. Different conceptualisations are highlighted, yet also limited focus on underlying dimensions of social capital and proactive types of resilience for engaging with the complex climate change challenge. Empirical insights show that structural and socio-cultural aspects of social capital, multiple other factors and formal actors are all important for shaping the role of social capital for guiding resilience outcomes. Thus, finding ways to work with these different elements is important. Greater attention on how and why outcomes emerge, interactions between factors, approaches of formal actors and different socio-cultural dimensions will advance understandings about how to nurture social capital for resilience in the context of climate change.

Glioblastomas (GBMs) are malignant central nervous system (CNS) neoplasms with a very poor prognosis. They display cellular hierarchies containing self-renewing tumourigenic glioma stem cells (GSCs) in a complex heterogeneous microenvironment. One proposed GSC niche is the extracellular matrix (ECM)-rich perivascular bed of the tumour. Here, we report that the ECM binding dystroglycan (DG) receptor is expressed and functionally glycosylated on GSCs residing in the perivascular niche. Glycosylated αDG is highly expressed and functional on the most aggressive mesenchymal-like (MES-like) GBM tumour compartment. Furthermore, we found that DG acts to maintain an MES-like state via tight control of MAPK activation. Antibody-based blockade of αDG induces robust ERK-mediated differentiation leading to reduced GSC potential. DG was shown to be required for tumour initiation in MES-like GBM, with constitutive loss significantly delaying or preventing tumourigenic potential in-vivo. These findings reveal a central role of the DG receptor, not only as a structural element, but also as a critical factor promoting MES-like GBM and the maintenance of GSCs residing in the perivascular niche. Electronic supplementary material The online version of this article (10.1007/s00401-019-02069-x) contains supplementary material, which is available to authorized users.

Enlarged vestibular aqueduct (EVA) is one of the most commonly identified inner ear malformations in hearing loss patients including Pendred syndrome. While biallelic mutations of the SLC26A4 gene, encoding pendrin, causes non-syndromic hearing loss with EVA or Pendred syndrome, a considerable number of patients appear to carry mono-allelic mutation. This suggests faulty pendrin regulatory machinery results in hearing loss. Here we identify EPHA2 as another causative gene of Pendred syndrome with SLC26A4. EphA2 forms a protein complex with pendrin controlling pendrin localization, which is disrupted in some pathogenic forms of pendrin. Moreover, point mutations leading to amino acid substitution in the EPHA2 gene are identified from patients bearing mono-allelic mutation of SLC26A4. Ephrin-B2 binds to EphA2 triggering internalization with pendrin inducing EphA2 autophosphorylation weakly. The identified EphA2 mutants attenuate ephrin-B2- but not ephrin-A1-induced EphA2 internalization with pendrin. Our results uncover an unexpected role of the Eph/ephrin system in epithelial function., While biallelic mutations of the SLC26A4 gene cause non-syndromic hearing loss with enlarged vestibular aqueducts or Pendred syndrome, a considerable number of patients carry mono-allelic mutations. Here the authors identify EPHA2 as another causative gene of Pendred syndrome with SLC26A4.

Glioblastomas (GBMs) are malignant central nervous system (CNS) neoplasms with a very poor prognosis. They display cellular hierarchies containing self-renewing tumourigenic glioma stem cells (GSCs) in a complex heterogeneous microenvironment. One proposed GSC niche is the extracellular matrix (ECM)-rich perivascular bed of the tumour. Here, we report that the ECM binding alpha (α) subunit of the dystroglycan (DG) receptor is expressed and functionally glycosylated on GSCs residing in the vascular niche. Glycosylated αDG is also expressed highly on the most aggressive mesenchymal-like GBM tumour tissue. Furthermore, we found that DG acts to maintain a de-differentiated stem cell-like phenotype via tight control of MAPK activation. Antibody-based blockade of αDG induces robust ERK-mediated differentiation leading to reduced GSC potential. DG was shown to be required for tumour initiation, with constitutive loss significantly delaying or preventing tumourigenic potential in-vivo. These findings reveal a central role of the DG receptor not only as a structural element but also as a critical factor in the maintenance of GSCs in the GBM vascular niche.

Background Despite significant endeavor having been applied to identify effective therapies to treat glioblastoma (GBM), survival outcomes remain intractable. The greatest nonsurgical benefit arises from radiotherapy, though tumors typically recur due to robust DNA repair. Patients could therefore benefit from therapies with the potential to prevent DNA repair and synergize with radiotherapy. In this work, we investigated the potential of salinomycin to enhance radiotherapy and further uncover novel dual functions of this ionophore to induce DNA damage and prevent repair. Methods In vitro primary GBM models and ex vivo GBM patient explants were used to determine the mechanism of action of salinomycin by immunoblot, flow cytometry, immunofluorescence, immunohistochemistry, and mass spectrometry. In vivo efficacy studies were performed using orthotopic GBM animal xenograft models. Salinomycin derivatives were synthesized to increase drug efficacy and explore structure-activity relationships. Results Here we report novel dual functions of salinomycin. Salinomycin induces toxic DNA lesions and prevents subsequent recovery by targeting homologous recombination (HR) repair. Salinomycin appears to target the more radioresistant GBM stem cell–like population and synergizes with radiotherapy to significantly delay tumor formation in vivo. We further developed salinomycin derivatives which display greater efficacy in vivo while retaining the same beneficial mechanisms of action. Conclusion Our findings highlight the potential of salinomycin to induce DNA lesions and inhibit HR to greatly enhance the effect of radiotherapy. Importantly, first-generation salinomycin derivatives display greater efficacy and may pave the way for clinical testing of these agents.

Glioblastoma (GBM) is an essentially incurable and rapidly fatal cancer, with few markers predicting a favourable prognosis. Here we report that the transcription factor NFIB is associated with significantly improved survival in GBM. NFIB expression correlates inversely with astrocytoma grade and is lowest in mesenchymal GBM. Ectopic expression of NFIB in low-passage, patient-derived classical and mesenchymal subtype GBM cells inhibits tumourigenesis. Ectopic NFIB expression activated phospho-STAT3 signalling only in classical and mesenchymal GBM cells, suggesting a mechanism through which NFIB may exert its context-dependent tumour suppressor activity. Finally, NFIB expression can be induced in GBM cells by drug treatment with beneficial effects.

The EphA3 receptor has recently emerged as a functional tumour-specific therapeutic target in glioblastoma (GBM). EphA3 is significantly elevated in recurrent disease, is most highly expressed on glioma stem cells (GSCs), and has a functional role in maintaining self-renewal and tumourigenesis. An unlabelled EphA3-targeting therapeutic antibody is currently under clinical assessment in recurrent GBM patients. In this study, we assessed the efficacy of EphA3 antibody drug conjugate (ADC) and radioimmunotherapy (RIT) approaches using orthotopic animal xenograft models. Brain uptake studies, using positron emission tomography/computed tomography (PET/CT) imaging, show EphA3 antibodies are effectively delivered across the blood-tumour barrier and accumulate at the tumour site with no observed normal brain reactivity. A robust anti-tumour response, with no toxicity, was observed using EphA3, ADC, and RIT approaches, leading to a significant increase in overall survival. Our current research provides evidence that GBM patients may benefit from pay-loaded EphA3 antibody therapies.

Eph receptors have emerged as targets for therapy in both neoplastic and non-neoplastic disease, however, particularly in non-neoplastic diseases, redundancy of function limits the effectiveness of targeting individual Eph proteins. We have shown previously that a soluble fusion protein, where the EphA4 ectodomain was fused to IgG Fc (EphA4 Fc), was an effective therapy in acute injuries and demonstrated that EphA4 Fc was a broad spectrum Eph/ephrin antagonist. However, a very short in vivo half-life effectively limited its therapeutic development. We report a unique glycoengineering approach to enhance the half-life of EphA4 Fc. Progressive deletion of three demonstrated N-linked sites in EphA4 progressively increased in vivo half-life such that the triple mutant protein showed dramatically improved pharmacokinetic characteristics. Importantly, protein stability, affinity for ephrin ligands and antagonism of cell expressed EphA4 was fully preserved, enabling it to be developed as a broad spectrum Eph/ephrin antagonist for use in both acute and chronic diseases.

The phrase ‘body-politic’ is often deployed to mean all of the people comprising a given ‘political’ unit, perhaps a country, nation or state, and sometimes conceived as the multitudes ruled over b...

What is the political allure, value and currency of emotions within contemporary cultures of governance? What does it mean to govern more humanely? Since the emergence of an emotional turn in human geography over the last decade, the notion that our emotions matter in understanding an array of social practices, spatial formations and aspects of everyday life is no longer seen as controversial. This book brings recent developments in emotional geography into dialogue with social policy concerns and contemporary issues of governance. It sets the intellectual scene for research into the geographical dimensions of the emotionalized states of the citizen, policy maker and public service worker, and highlights new research on the emotional forms of governance which now characterise public life.

Developing a critical analysis of the relational and situated practices of social policy, this paper draws on an evaluation of an early intervention project in Scotland (UK) where volunteer adult mentors supported young people ‘at risk’ of offending or antisocial behaviour. Contributing to ‘enlivened’ accounts of social practice, we explore how practices of mentoring developed through the co-presence of mentor and young person in the often transitory spaces of care which characterized the ‘diversionary activities’ approach in the project. We expand the notion of the relational in social practice beyond the care-recipient dyad to include wider networks of care (families, programme workers, social institutions). The paper explores how such social interventions might both be ‘good’ for the young people involved, and yet recognize critiques that more individualized models of intervention inevitably have limitations which make them ‘not enough’ to deal with structural inequalities and disadvantages. Acknowledging the impacts of neoliberalism, we argue critical attention to diverse situated relational practices points to the excessive nature of engagement in social policy and provides scope for transformative practice where young people’s geographies can be ‘upscaled’ to connect to the realms of social policy and practice. Résumé Développant une analyse critique de la politique sociale des pratiques relationnelles en situation, cet article s’appuie sur une évaluation d’un ancien programme d’intervention en Ecosse (Royaume-Uni), où des mentors adultes bénévoles aidaient des jeunes « en danger » de commettre un délit ou d’adopter un comportement antisocial. En apportant une contribution aux comptes rendus « animés » de politique sociale, nous explorons comment les pratiques de mentorat se sont développées à travers la coprésence d’un mentor et d’un jeune pendant les périodes souvent transitoires de prise en charge qui caractérisaient les approches d’« activités de diversion » de ce programme. Nous élargissons la notion du relationnel dans la pratique sociale au-delà de la dyade prise en charge-bénéficiaire en incluant les réseaux plus vastes de prise en charge (famille, acteurs du programme, institutions sociales). L’article explore dans quelle mesure les interventions sociales peuvent être « bonnes » pour les jeunes concernés mais reconnaît aussi les critiques que les modèles d’intervention plus individualisés ont inévitablement des limites qui les rendent « insuffisantes » pour gérer les inégalités et désavantages structuraux. Reconnaissant les effets du néolibéralisme, nous avançons l’argument que l’attention critique envers les diverses pratiques relationnelles en situation suggère la nature excessive de l’engagement politique social et donne la possibilité d’une pratique transformative où les géographies des jeunes peuvent être « améliorées » pour être reliées aux domaines de la politique et de la pratique sociales. Resumen Desarrollando un análisis crítico de las prácticas relacionales y situadas de la política social, este documento se basa en una evaluación de un proyecto de intervención temprana en Escocia (Reino Unido), donde mentores adultos voluntarios apoyaron a jóvenes ‘en riesgo’ de ofender o de mostrar un comportamiento antisocial. Contribuyendo a informes ‘animados’ de política social, se explora cómo se desarrollaron las prácticas de tutoría a través de la co-presencia de mentores y jóvenes en espacios a menudo transitorios de atención que caracterizaron el enfoque de las ‘actividades de distracción’ en el proyecto. Se amplía la noción de lo relacional en la práctica social más allá de la díada cuidado-receptor para incluir redes más amplias de cuidado (familias, trabajadores del programa, instituciones sociales). El trabajo explora cómo este tipo de intervenciones sociales podrían ser ‘buenas’ para los jóvenes involucrados y, sin embargo, al mismo tiempo, reconocer las críticas de que los modelos más individualizados de intervención tienen inevitablemente limitaciones que los hacen ‘no suficientes’ para hacer frente a desigualdades y desventajas estructurales. Reconociendo los impactos del neoliberalismo, se argumenta que la atención crítica a diversas prácticas relacionales situadas apunta al carácter excesivo de la participación en la política social y proporciona espacio para una práctica transformadora donde las geografías de los jóvenes pueden ‘aumentar de escala’ para conectarse con los dominios de la política y la práctica social.

This paper explores the motivations and meanings of international student mobility. Central to the discussion are the results of a large questionnaire survey and associated in-depth interviews with UK students enrolled in universities in six countries from around the world. The results suggest, first, that several different dimensions of social and cultural capital are accrued through study abroad. It is argued that the search for ‘world class’ education has taken on new significance. Second, the paper argues that analysis of student mobility should not be confined to a framework that separates study abroad from the wider life-course aspirations of students. It is argued that these insights go beyond existing theorisations of international student mobility to incorporate recognition of diverse approaches to difference within cultures of mobility, including class reproduction of distinction, broader notions of distinction within the life-plans of individual students, and how ‘reputations’ associated with educational destinations are structured by individuals, institutions and states in a global higher education system that produces differentially mediated geographies of international student mobility

Examining the everyday practices and feelings of volunteering, in particular their situated, emotional and embodied nature, serves to place the experiences of volunteers centrally in accounts of what matters in the doing of volunteering and goes beyond service provision or active citizenship. Using qualitative evidence from three collaborative research projects, we present enlivened geographies of volunteering which focus on: the situatedness of formal volunteering in place and the negotiation of local ‘moral economies’ of norms and expectations surrounding access to volunteering opportunities and the practices of volunteering; complex positionings of informal volunteering in biographies of social participation; and intersections of embodiment and emotions in experiences among environmental volunteers. We contribute to the development of social geographies which are ‘more-than-representational’ and argue that connecting insights on everyday practices of volunteering with wider policy and practice...

This article explores intersections between academic work and emotional work at a feminist geography reading weekend held by the Women and Geography Study Group of the Royal Geographical Society-Institute of British Geographers in the UK in 2006. It points to the importance of the fleeting, often unreported, spaces of feminist geographical praxis and of inserting these in our disciplinary histories. Using a performative textual strategy it offers a poly-vocal reflection on the complex, challenging and productive experiences of this kind of academic workspace. In so doing it contributes to feminist engagements with the practices of neo-liberal academia, to debates about the emotional geographies of feminist geographical work, and to discussions of the value of activities outside the norms of academia in providing potentially supportive and creative spaces for geographical praxis.

Objective: Histamine is a chemical mediator that acts at four known types of histamine receptors and has been widely implicated in the development of nociception and neuropathic pain. Blocking histamine H1 and H2 receptors has been shown to reduce hyperalgesia following nerve injury, but the role of histamine H3 and H4 receptors in neuropathic pain has not been studied. Here, we used blockers of histamine H3 and H4 receptors to assess their effects on neuropathic pain behavior and mast cell numbers following peripheral nerve injury. In addition, we assessed the effect of activating H4 receptors on neuropathic pain behavior. Methods: Rats were subjected to a partial ligation of the sciatic nerve, a model of neuropathic pain, and were treated either systemically or locally (hindpaw) with the H3/H4 receptor inverse agonist thioperamide, the specific H4 receptor antagonist JNJ 7777120, or the H4 receptor agonist VUF 8430. Measurements of mechanical hyperalgesia were carried out by Randall-Selitto test for 1–3 weeks, and sciatic nerve tissues were analyzed for numbers of intact mast cells by histology at 9 h after surgery. Results: Rats treated with thioperamide or JNJ 7777120 showed significantly enhanced mechanical hyperalgesia after partial ligation of the sciatic nerve. The number of intact mast cells in the injured nerve of these rats was higher than in control rats suggesting reduced mast cell degranulation, but was still significantly lower than in intact nerves. Rats treated with VUF 8430 showed significantly reduced mechanical hyperalgesia. Conclusion: We propose that the increase in mechanical hyperalgesia produced by thioperamide and JNJ 7777120 and the decrease in mechanical hyperalgesia produced by VUF 8430 may represent a direct effect of these agents on mechanospecific primary afferents, or an indirect effect of these agents via injury-induced inflammation.

Members of the Eph family of receptor tyrosine kinases and their membrane bound ephrin ligands have been shown to play critical roles in many developmental processes and more recently have been implicated in both normal and pathological processes in post-embryonic tissues. In particular, expression studies of Eph receptors and limited functional studies have demonstrated a role for the Eph/ephrin system in hematopoiesis and leukemogenesis. In particular, EphA2 was reported on hematopoietic stem cells and stromal cells. There are also reports of EphA2 expression in many different types of malignancies including leukemia, however there is a lack of knowledge in understanding the role of EphA2 in hematopoiesis and leukemogenesis. We explored the role of EphA2 in hematopoiesis by analyzing wild type and EphA2 knockout mice. Mature, differentiated cells, progenitors and hematopoietic stem cells derived from knockout and control mice were analyzed and no significant abnormality was detected. These studies showed that EphA2 does not have an obligatory role in normal hematopoiesis. Comparative studies using EphA2-negative MLL-AF9 leukemias derived from EphA2-knockout animals showed that there was no detectable functional role for EphA2 in the initiation or progression of the leukemic process. However, expression of EphA2 in leukemias initiated by MLL-AF9 suggested that this protein might be a possible therapy target in this type of leukemia. We showed that treatment with EphA2 monoclonal antibody IF7 alone had no effect on tumorigenicity and latency of the MLL-AF9 leukemias, while targeting of EphA2 using EphA2 monoclonal antibody with a radioactive payload significantly impaired the leukemic process. Altogether, these results identify EphA2 as a potential radio-therapeutic target in leukemias with MLL translocation.

Scotland's post-devolution government has implemented a number of policies engaging with the third sector. These sit within the UK context of New Labour's welfare reform with its twin emphases on neoliberalism and neo-communitarianism. Moves by the Scottish Executive to translate these themes into the Scottish context are illustrated by policies on the relation between the state and third sector organizations, on the social economy, and on volunteering. However, as a case study of the sector in Glasgow demonstrates, significant challenges emerge for the realization of policy claims for the development of social capital and citizenship in practice.

There is an urgent need for high purity, single chain, fully functional Eph/ephrin membrane proteins. This report outlines the pTIg-BOS-Fc vector and purification approach resulting in rapid increased production of fully functional single chain extracellular proteins that were isolated with high purity and used in structure-function analysis and pre-clinical studies.

Debates about geographical practice in Europe are explored through the spaces and practices of an undergraduate field-course in the Costa Blanca in Spain. Students encounter ‘Spain’ and ‘Europe’ through diversely embodied engagements and material encounters with familiarity and difference, inclusion and exclusion, which offer possibilities for de-centring dominant Anglo-American geographies and understanding the diverse practices which produce geographical knowledges.

Eph receptor tyrosine kinases (Ephs) function as molecular relays that interact with cell surface-bound ephrin ligands to direct the position of migrating cells. Structural studies revealed that, through two distinct contact surfaces on opposite sites of each protein, Eph and ephrin binding domains assemble into symmetric, circular heterotetramers. However, Eph signal initiation requires the assembly of higher order oligomers, suggesting additional points of contact. By screening a random library of EphA3 binding-compromised ephrin-A5 mutants, we have now determined ephrin-A5 residues that are essential for the assembly of high affinity EphA3 signaling complexes. In addition to the two interfaces predicted from the crystal structure of the homologous EphB2.ephrin-B2 complex, we identified a cluster of 10 residues on the ephrin-A5 E alpha-helix, the E-F loop, the underlying H beta-strand, as well as the nearby B-C loop, which define a distinct third surface required for oligomerization and activation of EphA3 signaling. Together with a corresponding third surface region identified recently outside of the minimal ephrin binding domain of EphA3, our findings provide experimental evidence for the essential contribution of three distinct protein-interaction interfaces to assemble functional EphA3 signaling complexes.

The EphA3 receptor tyrosine kinase preferentially binds ephrin-A5, a member of the corresponding subfamily of membrane-associated ligands. Their interaction regulates critical cell communication functions in normal development and may play a role in neoplasia. Here we describe a random mutagenesis approach, which we employed to study the molecular determinants of the EphA3/ephrin-A5 recognition. Selection and functional characterization of EphA3 point mutants with impaired ephrin-A5 binding from a yeast expression library defined three EphA3 surface areas that are essential for the EphA3/ephrin-A5 interaction. Two of these map to regions identified previously in the crystal structure of the homologous EphB2-ephrin-B2 complex as potential ligand/receptor interfaces. In addition, we identify a third EphA3/ephrin-A5 interface that falls outside the structurally characterized interaction domains. Functional analysis of EphA3 mutants reveals that all three Eph/ephrin contact areas are essential for the assembly of signaling-competent, oligomeric receptor-ligand complexes.

The purpose of this paper is to introduce the present Special Issue of Space & Polity tackling the political geographies of children and young people. Historically given scant attention by the sub-discipline, since children and young people appear to have little active influence on the workings of states, nations, geopolitics and the like, there are now small signs of how and why political geographers might look anew at the experiences and contribu tions of this population cohort. An empirical vignette, based on letters written by children and young people to Eleanor Roosevelt during the Great De pression, is deployed to develop this claim. Contrasts are then drawn between political geographies of children and young people that are ‘adult-centred’ and those that are ‘child-centred’, as related to claims about the distinctions and connections between ‘macro-politics’ and ‘micro-politics’. It is suggested that, notwithstanding the exciting insights to be derived from child-centred approaches, the situation ...

During recent decades there has been a change in the circulation of atmospheric pressure throughout the Northern Hemisphere. These variations are expressed in the recently described Arctic Oscillation (AO), which has shown an upward trend (associated with winter warming in the eastern Arctic) during the last three decades. We analysed a 12-year time series on growth of Cassiope tetragona (Lapland Cassiope) and a 21-year time series on abundance of a Svalbard reindeer population. High values of the AO index were associated with reduced plant growth and reindeer population growth rate. The North Atlantic Oscillation index was not able to explain a significant proportion of the variance in either plant growth or reindeer population fluctuations. Thus, the AO index may be a better predictor for ecosystem effects of climate change in certain high-arctic areas compared to the NAO index.

1. Introduction. 2. Changing Worlds? Changing Femininities? 3. Methodologies for Mapping Geographies of Multiple Feminine Identities. 4. Opportunities and Contradictory Space? . 5. Reluctant Westerners. 6. Merely Diffferent Cultures of Mothering?. 7. Negotiating Stereotypes. 8. New Femininities & Negotiations of Geographies. 9. Conclusions: New Femininities?

Diversely gendered experiences of post-unification Germany are examined in relation to dominant neo-liberal scripts of post-Cold War restructuring and the tropes of 'East' and 'West' underpinning reunification. This provides a possible framework for feminist geopolitics where geopolitics are 'refigured' in three ways: assessing the relation of gender to the discursive practices of geopolitics; addressing the use and contestation of geopolitical discourse by gendered subjects in the 'small transformations' of everyday life; and repopulating the landscapes of geopolitics to focus on issues of 'human security' in the cross-scale interactions of state, nation, economy, polity, family and the embodied (gendered) subject.

1. The ATP-activated P2X2(a) and P2X2(b) receptor splice variants, which differ only in their C-terminal sequences, desensitize at different rates. We used mutational analysis to investigate the involvement of the C-terminal region in receptor desensitization. Rat wild-type and mutant P2X2 receptors were expressed in Xenopus oocytes and currents were measured using the two-electrode voltage-clamp technique. 2. Truncating P2X2 at the Lys369 splice site increased the rate of desensitization by >100-fold. Recovery from desensitization was slowed by approximately 5-fold. 3. Addition of Val370 onto the C-terminus of the truncated receptor slowed desensitization by approximately 70-fold. Point mutations that substituted either smaller or larger hydrophobic amino acids for Val370, within the P2X2(a) splice variant, had profound effects on the rate of desensitization. The rate decreased with increasing hydrophobicity but was not dependent upon the precise structure of the side group. 4. A mutant receptor, with only nine amino acids, Val-Asp-Pro-Lys-Gly-Leu-Ala-Gln-Leu, beyond the Lys369 splice site, desensitized at a similar rate to P2X2(a). Injection of the peptide of this sequence into oocytes expressing P2X2(a) increased the rate of desensitization, whereas the eight-residue peptide lacking the valine had no effect. 5. Neutralizing lysines in the vicinity of the splice site increased the rate of receptor desensitization. Substituting glutamine for Lys365 produced the greatest effect ( approximately 30-fold increase), whereas mutating lysines that were further upstream or downstream of this position had progressively less of an effect. 6. We conclude that the C-terminal splice site of the P2X2 receptor is located within a region that is critically involved in regulating the rate of receptor desensitization. The valine at position 370 interacts with an intracellular hydrophobic site to slow the rate of desensitization. Nearby lysines may facilitate this interaction.

Geographical understandings of citizenship and insights from studies of post-communist transitions inform an examination of discourses and processes of urban change in the city of Leipzig, eastern Germany. Dominant public discourses shaped by citizens and elites include demands for `careful urban renewal' and 'citizen participation', rejections of party-politics in local action and collective aims of working 'for the good of the city'. All come under pressure from processes of economic liberalisation. Discourses operate through and work to redefine the positions of 'experts', 'citizens' and 'residents' in the scales of the 'city' and the 'local' and produce complex and contested relations of power and control in specific material situations where space, place and scale are more than passive containers of action.

Geopolitics and city restructuring are typically regarded as separate scales and processes: the international and national versus the local. The local politics of urban change in an east German city in the period after reunification question this divide. The ‘pathways’ approach to post-socialist transitions is utilized to illustrate how reunification is contested as much in neighbourhood restructuring and actions in response to incoming capital and the dominance of western legalpolitical norms as it is in national or international discourses and practices. Assumed divisions between East and West, professional and lay, and local and national are questioned.

Ownership represents a key relation between people and places. Eastern European transformations since the late 1980s confront western norms of private property rights within a capitalist system with the legacies of an alternative ownership system and with attempts to establish property markets from first principles. The developments in the former GDR and in eastern Germany after German reunification offer an opportunity to question assumptions of use and value which underlie western models of property tenure. While common themes of privatisation and commodification link eastern and western experiences, the particular manifestations of transformations in eastern Germany challenge the claims of the primacy of ownership and the legitimacy of claims for control over the built environment.

The union of the two postwar German states appealed to a shared historical experience of ‘Germany’ justifying reunification. At the same time divergent lived experiences of 40 years on either side of the Iron Curtain mean that reunification is not the mirror image of division. There has to be readjustment from both sides at various spatial scales. Meaning and significance must be bargained for, requiring restructuring and renewed realignment at all scales. This process is placed in the broader theoretical context which considers the spectrum of nation-state formation and division, partition and reunification, involving the interrelationships between spatial scales, historical developments, economic and political aims, symbolisms of place and geopolitical concerns. Two examples illustrate the contested nature of this restructuring at regional, national and European levels: the fate of the Zonal Border Area regional development programme and the Bonn-Berlin debate of 1991.

Aberrant expression of Eph and ephrin proteins in human cancers is extensively documented. However, data are frequently limited to one gene and therefore incomplete and in some instances conflicting. We analysed expression of all Eph and ephrin genes in colorectal cancer (CRC) cell lines and 153 clinical specimens, providing for the first time a comprehensive analysis of this system in CRC. Eph/ephrin mRNA expression was assessed by quantitative real-time PCR and correlated with protein expression (flow cytometry, Western blotting and immunocytochemistry). These data show that EphA1, EphA2, EphB2 and EphB4 were significantly over expressed in CRC. In all cases, at least one Eph gene was found in normal colon (EphA1, EphA2, EphB2, EphB4), where expression was observed at high levels in most CRCs. However, other Eph gene expression was lost in individual CRCs compared to the corresponding normal, EphA7 being a striking example. Loss of expression was more common in advanced disease and thus correlated with poor survival. This is consistent with the redundant functionality of Eph receptors, such that expression of a single Eph gene is sufficient for effector function. Overall, the data suggest a progressive loss of expression of individual Eph genes suggesting that individual CRCs need to be phenotyped to determine which Eph genes are highly expressed. Targeted therapies could then be selected from a group of specific antibodies, such as those developed for EphA1.

Histamine is a chemical mediator that acts at four known types of histamine receptors and has been widely implicated in the development of nociception and neuropathic pain. Blocking histamine H(1) and H(2) receptors has been shown to reduce hyperalgesia following nerve injury, but the role of histamine H(3) and H(4) receptors in neuropathic pain has not been studied. Here, we used blockers of histamine H(3) and H(4) receptors to assess their effects on neuropathic pain behavior and mast cell numbers following peripheral nerve injury. In addition, we assessed the effect of activating H(4) receptors on neuropathic pain behavior.Rats were subjected to a partial ligation of the sciatic nerve, a model of neuropathic pain, and were treated either systemically or locally (hindpaw) with the H(3)/H(4) receptor inverse agonist thioperamide, the specific H(4) receptor antagonist JNJ 7777120, or the H(4) receptor agonist VUF 8430. Measurements of mechanical hyperalgesia were carried out by Randall-Selitto test for 1-3 weeks, and sciatic nerve tissues were analyzed for numbers of intact mast cells by histology at 9 h after surgery.Rats treated with thioperamide or JNJ 7777120 showed significantly enhanced mechanical hyperalgesia after partial ligation of the sciatic nerve. The number of intact mast cells in the injured nerve of these rats was higher than in control rats suggesting reduced mast cell degranulation, but was still significantly lower than in intact nerves. Rats treated with VUF 8430 showed significantly reduced mechanical hyperalgesia.We propose that the increase in mechanical hyperalgesia produced by thioperamide and JNJ 7777120 and the decrease in mechanical hyperalgesia produced by VUF 8430 may represent a direct effect of these agents on mechanospecific primary afferents, or an indirect effect of these agents via injury-induced inflammation.

To investigate levels of eating pathology in female adolescents diagnosed with a chronic condition causing appearance change (adolescent-onset idiopathic scoliosis), a chronic condition affecting nutritional behavior (insulin-dependent diabetes mellitus), and healthy age-matched controls.Cross-sectional comparison of 192 females aged 11-19 years; 76 individuals diagnosed with scoliosis, 40 diagnosed with diabetes, and 76 control participants. Disordered eating behavior was quantified using the Eating Disorder Examination Questionnaire, and weight and body mass index (weight [kg]/height [m(2)]) measurements were taken for each participant.The scoliosis group weighed less and had lower BMI scores (p.001) than control participants. Of the participants with scoliosis, 25% were severely underweight, but only two met the behavioral criteria for anorexia nervosa; in others no association with disordered eating behaviour was found. Eating disorders were significantly more common (p.05) in the diabetes participants than in the control group, with 27.5% of the group classified as having bulimia or binge eating disorder. All those classified as overweight or obese in the diabetes group were classified as pathological in terms of eating behavior.The relationship between scoliosis and low body mass is a concern but is not a result of an eating disorder. Etiological mechanisms remain unclear and require further investigation. In the diabetes participants, bulimia and binge eating may prejudice effective condition management. Implications for successful adaptation, treatment intervention, and future research are discussed.

Molinate causes an impairment in reproductive capability in the male rat. Administration of molinate to rats (40 mg/kg/day for 7 days) caused a distinctive sperm lesion. At higher doses of molinate (140 mg/kg for 7 days) this lesion was accompanied by morphological changes to the testis that were consistent with a delayed release of the late spermatids to the seminiferous tubular lumen, a process controlled by the release of testosterone. In accordance with this, molinate (>/=40 mg/kg) caused a marked decrease in the concentration of circulating and testicular testosterone. The Leydig cells of the testis appear to be the primary target site in that radiolabel from [3H]molinate specifically localized within this cell type. In addition, esterase activity in the Leydig cells was inhibited following molinate administration. In vitro, molinate is a poor inhibitor of esterase activity, whereas molinate sulfoxide, a major metabolite of molinate in rats, and molinate sulfone were shown to be potent inhibitors of this process, suggesting that metabolic activation of molinate is required in vivo. Molinate sulfoxide (>/=10 mg/kg) caused an identical sperm lesion to that of molinate and markedly decreased plasma and testicular testosterone concentration. These effects were not seen with the molinate metabolites 4-hydroxymolinate (10 mg/kg), molinate sulfone (10 mg/kg), and hexamethyleneimine (10 mg/kg). Since the sperm lesion is a secondary event caused by a disruption of spermatogenesis, this would imply that the testis lesion and the reproductive impairment are also a consequence of molinate sulfur oxidation.

Eph receptor tyrosine kinases and their ligands (ephrins) are highly conserved protein families implicated in patterning events during development, particularly in the nervous system. In a number of functional studies, strict conservation of structure and function across distantly related vertebrate species has been confirmed. In this study we make use of the observation that soluble human EphA3 (HEK) exerts a dominant negative effect on somite formation and axial organization during zebrafish embryogenesis to probe receptor function. Based on exon structure we have dissected the extracellular region of EphA3 receptor into evolutionarily conserved subdomains and used kinetic BIAcore analysis, mRNA injection into zebrafish embryos, and receptor transphosphorylation analysis to study their function. We show that ligand binding is restricted to the N-terminal region encoded by exon III, and we identify an independent, C-terminal receptor- dimerization domain. Recombinant proteins encoding either region in isolation can function as receptor antagonists in zebrafish. We propose a two-step mechanism of Eph receptor activation with distinct ligand binding and ligand- independent receptor-receptor oligomerization events.

Advances in screening technologies allowing the identification of growth factor receptors solely by virtue of DNA or protein sequence comparison call for novel methods to isolate corresponding ligand growth factors. The EPH-like receptor tyrosine kinase (RTK) HEK (human EPH-like kinase) was identified previously as a membrane antigen on the LK63 human pre-B-cell line and overexpression in leukemic specimens and cell lines suggested a role in oncogenesis. We developed a biosensor-based approach using the immobilized HEK receptor exodomain to detect and monitor purification of the HEK ligand. A protein purification protocol, which included HEK affinity chromatography, achieved a 1.8 X 10(6)-fold purification of an approximately 23-kDa protein from human placental conditioned medium. Analysis of specific sHEK (soluble extracellular domain of HEK) ligand interactions in the first and final purification steps suggested a ligand concentration of 40 pM in the source material and a Kd of 2-3 nM. Since the purified ligand was N-terminally blocked, we generated tryptic peptides and N-terminal amino acid sequence analysis of 7 tryptic fragments of the S-pyridylethylated protein unequivocally matched the sequence for AL-1, a recently reported ligand for the related EPH-like RTK REK7 (Winslow, J.W., Moran, P., Valverde, J., Shih, A., Yuan, J.Q., Wong, S.C., Tsai, S.P., Goddard, A., Henzel, W.J., Hefti, F., Beck, K.D., & Caras, I.W. (1995) Neuron 14, 973-981). Our findings demonstrate the application of biosensor technology in ligand purification and show that AL-1, as has been found for other ligands of the EPH-like RTK family, binds more than one receptor.

Eph and its homologues form the largest subfamily of receptor tyrosine kinases. Normal expression patterns of this subfamily indicate roles in differentiation and development, whereas their overexpression has been linked to oncogenesis. This study investigated the potential role of Eph-related molecules during very early embryonic development by examining their expression in embryonic stem (ES) cells and embryoid bodies differentiated from ES cells in vitro. By use of a strategy based on reverse transcriptase-mediated PCR, nine clones containing Eph-subfamily sequence were isolated from ES cells. Of these, eight were almost identical to one of four previously identified molecules (Sek, Nuk, Eck, and Mek4). However, one clone contained sequence from a novel Eph-subfamily member, which was termed embryonic stem-cell kinase or Esk. Northern analysis showed expression of Esk in ES cells, embryoid bodies, day 12 mouse embryos, and some tissues of the adult animal. Levels of expression were similar in ES cells and embryoid bodies. By comparison, Mek4 showed no significant transcription in the ES cell cultures by Northern analysis, whereas Eck displayed stronger signals in ES cells than in the embryoid bodies. These results suggest that Eph-subfamily molecules may play roles during the earliest phases of embryogenesis. Furthermore, the relative importance of different members of this subfamily appears to change as development proceeds.

cDNAs encoding three splice variants of the P2X2 receptor were isolated from rat cerebellum. The first variant has a serine/proline-rich segment deleted from the intracellularly located carboxyl-terminal domain of the P2X2 subunit. The second and third variants have the splice site in the second half of the predicted first transmembrane domain. Either a 12-amino acid insertion or a six-amino acid deletion occurs at this position. cRNAs for these isoforms of the P2X2 subunit were injected into Xenopus laevis oocytes and tested for function. ATP evoked inward currents only with the splice variant [designated P2X2(b)] having the 69-amino acid deletion. The potencies of various agonists at the homomeric P2X2(b) receptor were not significantly different from those at the P2X2(a) homomeric channel. However, the P2X2(b) receptor showed significantly lower antagonist sensitivity. In contrast to the nondesensitizing P2X2(a) receptor, prolonged application of ATP produced a more rapid desensitization of the P2X2(b) receptor. When the P2X2(a) and P2X2(b) receptor responses were recorded in transfected mammalian cells, this difference was again found. The change in desensitization may be determined by proline/serine-rich segments and/or phosphorylation motifs that are removed from the tail region in formation of the P2X2(b) subunit. In situ hybridization of the three newly isolated isoforms of the P2X2 subunit was performed at the macroscopic and cellular levels; transcripts for two of them [P2X2(b) and p2x2(c)] but not the third [p2x2(d)], which carries the 12-amino acid addition, were present in many structures in the neonatal rat brain and on sensory and sympathetic ganglia. mRNA for the p2x2(d) splice variant was present only in the nodose ganglion, at a low level.