The role of the 8-18 helix of CGRP 8-37 in mediating high affinity binding to CGRP receptors; coulombic and steric interactions

1. The role of individual residues in the 8-18 helix of CGRP 8-37 in promoting high-affinity binding to CGRP 1 receptors expressed on rat L6 and human SK-N-MC cells has been examined. The relative potencies of various derivatives were estimated from their ability to inhibit the human αCGRP-mediated increase in cyclic AMP production and the binding of [ 125I]-human αCGRP. 3. Arg 11 and Arg 18 were replaced by serines to give [Ser 11.18]CGRP 8-37. These bound with pKi values <6 to SK-N-MC cells and had apparent pA 2 values of 5.81 ± 0.04 and 5.31 ± 0.11 on SK-N-MC and L6 cells. CGRP 8-37 had a pKi of 8.22 on SK-N-MC cells and pK b values on the above cell lines of 8.95±0.04 and 8.76±0.04. 3. The arginines were replaced with glutamic acid residues. [Glu 11]CGRP 8-37 had a pK b of 7.14±0.14 on SK-N-MC cells (pKi=7.05±0.05) and 6.99±0.08 on L6 cells. [Glu 18]CGRP 8-37 had a pK b of 7.10±0.0.08 on SK-N-MC cells (pKi=6.91±0.23) and 7.12±0.09 on L6 cells. 4. Leu 12, Leu 15 and Leu 16 were replaced by benzoyl-phenylalanine (bpa) residues. On SK-N-MC cells, the apparent pA 2 values of [bpa 12]-, [bpa 15]- and [bpa 16]CGRP 8-37 were respectively 7.43±0.23, 8.34±0.11 and 5.66±0.16 (pKi values of 7.14±0.17, 7.66±0.21 and <6): on L6 cells they were 7.96±0.36, 8.28±0.21 and 6.09±0.04 (all n=3). 5. It is concluded that the Arg 11 and Arg 18 are involved in specific electrostatic interactions with other residues, either on the CGRP 1 receptors or elsewhere on CGRP 8-37. Leu 16 is in a conformationally restricted site when CGRP 8-37 binds to CGRP 1 receptors, unlike Leu 12 and Leu 15.

The role of the innate immune system in the clearance of apoptotic cells

Rapid clearance of dying cells is a vital feature of apoptosis throughout development, tissue homeostasis and resolution of inflammation. The phagocytic removal of apoptotic cells is mediated by both professional and amateur phagocytes, armed with a series of pattern recognition receptors that participate in host defence and apoptotic cell clearance. CD14 is one such molecule. It is involved in apoptotic cell clearance (known to be immunosuppressive and anti-inflammatory) and binding of the pathogen-associated molecular pattern, lipopolysaccharides (a pro-inflammatory event). Thus CD14 is involved in the assembly of two distinct ligand-dependent macrophage responses. This project sought to characterise the involvement of the innate immune system, particularly CD14, in the removal of apoptotic cells. The role of non-myeloid CD14 was also considered and the data suggests that the expression of CD14 by phagocytes may define their professional status as phagocytes. To assess if differential CD14 ligation causes the ligand-dependent divergence in macrophage responses, a series of CD14 point mutants were used to map the binding of apoptotic cells and lipopolysaccharides. Monoclonal antibodies, 61D3 and MEM18, known to interfere with ligand-binding and responses, were also mapped. Data suggests that residue 11 of CD14, is key for the binding of 61D3 (but not MEM18), LPS and apoptotic cells, indicating lipopolysaccharides and apoptotic cells bind to similar residues. Furthermore using an NF-kB reporter, results show lipopolysaccharides but not apoptotic cells stimulate NF-kB. Taken together these data suggests ligand-dependent CD14 responses occur via a mechanism that occurs downstream of CD14 ligation but upstream of NF-?B activation. Alternatively apoptotic cell ligation of CD14 may not result in any signalling event, possibly by exclusion of TLR-4, suggesting that engulfment receptors, (e.g. TIM-4, BAI1 and Stablin-2) are required to mediate the uptake of apoptotic cells and the associated anti-inflammatory response.

An examination of the role of the concept of the community within the current reorganisation of English local government

The thesis will examine the role and impact of the concept of the community within the structural reorganisation of English local government between 1992 and 1995. The methodological approach adopted within this thesis has been to compare the use, application and significance of the community with a case study of a specific local authority and its preparations for reorganisation. The authority in question was Wychavon District Council located in the County of Hereford and Worcester. The conclusions from this case study were then compared to the role and significance of the community in the reviews of other local authorities in England. This study produced two important results. These were that there was an established body of literature which argued that the community could be of value to local government and that the community should be identified by measuring individuals sense of belonging and feelings of attachment, as well as such daily activities as shopping and working (which help to stimulate these feelings). The then Conservative Government even instructed the specially appointed Commission to apply this particular interpretation of the community to their reviews, and to attempt to base any new unitary authorities upon the social and spatial area it created. The Conservative Government also gave the Commission a Community Index to assist with the identification of communities, and appointed the pollsters MORI to support the Commission with the task of identifying the emotional and more subjective senses of community. The Commission eventually came to rely entirely on the MORI polls, and whilst these polls attempted to faithfully apply the Governments interpretation of the community, they unfortunately produced small and often complex communities, which the Commission felt could not be applied to its reviews. This therefore led to the community becoming a secondary consideration to the factors of cost and efficiency. Furthermore the problematic nature of the community - that is, the production of small and complex communities - was repeated in this thesis' own survey of community identities in the District of Wychavon. In fact this authority's proposals for reorganisation were based almost entirely upon the factors of cost, size and efficiency.

Auditor's engagement risk and audit fees:the role of the audit firm alumni

This study explores the effect of the association of audit firm alumni with their alma mater on audit prices. The tests indicate that there is a moderate reduction of up to 21% in the level of audit fee when alumni (i.e., former employees) of the incumbent audit firm sit on the client board of directors which is consistent with the engagement risk theory. This suggests that there is an 'alumni effect' in the market for audit services. The findings hold only in the large company segment of the market. The results are robust to different model specifications and alternative samples. The sample comprises all executive and non-executive directors who run the UK quoted companies and are simultaneously ICAEW qualified chartered accountants. The study's implications for the accounting profession and the regulators are also discussed. © 2007 The Author Journal compilation © 2007 Blackwell Publishing Ltd.

"Making it all normal": the role of the Internet in problematic pregnancy

Women are actively encouraged to educate themselves about pregnancy from formal sources (e.g., information leaflets, antenatal classes, books). In addition, informal stories of pregnancy and birth are routinely told between women. However, increased prenatal testing means that more fetuses are diagnosed with abnormalities, shifting the information requirements during pregnancy. Traditional sources of information cannot cover all possible outcomes, and the Internet is beginning to fill this gap. In this article, we draw from interviews about experiences of antenatal screening and pregnancy to explore how the Internet provides a unique resource for problematic pregnancies. It allows access to information about rarer conditions beyond standard pregnancy texts, as well as personal narratives about conditions. Learning how others have coped or are coping in similar situations can help alleviate feelings of isolation, and also places women back in a familiar territory of shared pregnancy narratives.

The Role of the big five personality traits, proactive behaviour, and socialisation influences in newcomer adjustment

During the early stages of employment, newly hired employees find out what their new organisations are like. Their first impressions are extremely important in determining the course of subsequent attitudes and behaviour. Recently, a considerable progress has been made towards the understanding of adjustment process, however, the literature remain divided along a number of fronts. Moreover, newcomer research has been conducted independent and irrespective of newcomer personality individual differences. This seems to be a critical oversight because there is overlap in predictions involving these constructs. The current research extended the previous one by examining these multiple antecedents, including Big Five personality traits of newcomer to the tandem process of adjustment as well as outcomes that immediate, or ?proximal? to the process of newcomer adjustment. Following a cross sectional pilot study of recent college graduate, a three- wave longitudinal study of newcomers in seven organisations examined Big Five personality traits, proactive behaviour, and socialisation influence (formal training, leaders, co-workers) as antecedents of proximal adjustment outcomes (group integration, political knowledge of organisation, and task performance). The main study results suggested that personality traits were related to proximal adjustment outcomes, specifically, Conscientiousness was positively related to all proximal adjustment outcomes. Openness to experience was related to task performance and political knowledge. Group integration is independently related to Agreeableness, Extraversion and Neuroticism. The socialisation influence moderate these relations, for example, leader socialisation moderate Conscientiousness as it relates to political knowledge and group integration, while co-worker moderate Extraversion as it relates to task performance. Finally, it was found that, the relationship between proximal adjustment outcomes and the personality dimensions Openness was mediated by proactive behaviour. Overall, the results suggested that individual differences have a role in newcomer adjustment as it facilitate the socialisation influence, and Big Five was one of the key determinants of newcomer adjustment.

Origins of molecular neurobiology:The role of the physicists

The revolution in the foundations of physics at the beginning of the twentieth century suggested to several of its most prominent workers that biology was ripe for something similar. In consequence, a number of physicists moved into biology. They were highly influential in initiating a molecular biology in the 1950s. Two decades later it seemed to several of these migrants, and those they had influenced, that the major problems in molecular biology had been solved, and that it was time to move on to what seemed to them the final problem: the nervous system, consciousness, and the age-old mind-body problem. This paper reviews this "double migration" and shows how the hopes of the first generation of physicist-biologists were both realized and dashed. No new physical principles were discovered at work in the foundations of biology or neuroscience. On the other hand, the mind-set of those trained in physics proved immensely valuable in analyzing fundamental issues in both biology and neuroscience. It has been argued that the outcome of the molecular biology of the 1950s was a change in the concept of the gene from that of "a mysterious entity into that of a real molecular object" (Watson, 1965, p.6); the gates and channels which play such crucial roles in the functioning of nervous systems have been transformed in a similar way. Studies on highly simplified systems have also opened the prospect of finding the neural correlatives of numerous behaviors and neuropathologies. This increasing understanding at the molecular level is invaluable not only in devising rational therapies but also, by defining the material substrate of consciousness, in bringing the mind-body problem into sharper focus. Copyright © Taylor & Francis Inc.

Attentional shifting and the role of the dorsal pathway in visual word recognition

A substantial amount of evidence has been collected to propose an exclusive role for the dorsal visual pathway in the control of guided visual search mechanisms, specifically in the preattentive direction of spatial selection [Vidyasagar, T. R. (1999). A neuronal model of attentional spotlight: Parietal guiding the temporal. Brain Research and Reviews, 30, 66-76; Vidyasagar, T. R. (2001). From attentional gating in macaque primary visual cortex to dyslexia in humans. Progress in Brain Research, 134, 297-312]. Moreover, it has been suggested recently that the dorsal visual pathway is specifically involved in the spatial selection and sequencing required for orthographic processing in visual word recognition. In this experiment we manipulate the demands for spatial processing in a word recognition, lexical decision task by presenting target words in a normal spatial configuration, or where the constituent letters of each word are spatially shifted relative to each other. Accurate word recognition in the Shifted-words condition should demand higher spatial encoding requirements, thereby making greater demands on the dorsal visual stream. Magnetoencephalographic (MEG) neuroimaging revealed a high frequency (35-40 Hz) right posterior parietal activation consistent with dorsal stream involvement occurring between 100 and 300 ms post-stimulus onset, and then again at 200-400 ms. Moreover, this signal was stronger in the shifted word condition, compared to the normal word condition. This result provides neurophysiological evidence that the dorsal visual stream may play an important role in visual word recognition and reading. These results further provide a plausible link between early stage theories of reading, and the magnocellular-deficit theory of dyslexia, which characterises many types of reading difficulty. © 2006 Elsevier Ltd. All rights reserved.

The role of the undergraduate work placement in developing employment competences:results from a 5 year study of employers

There is increasing research interest into the nature of competences required to secure a graduate job. This paper examines the role of the undergraduate work placement in developing such employment competences. In order to do this we draw upon a framework of generic competences developed in a previous project by one of the authors, together with data on how these competences are valued by graduates and employers. We also draw upon a survey of employers and students who have participated in an Aston Business School work placement. The work placement year is an integral feature of Aston’s undergraduate business programme and gives up to 600 students a year the experience of working with well known companies. For the past five years we have conducted a survey of these companies to assess their experience of employing our undergraduates on work placements and to examine the skills and competencies developed by students in the learning process. In this paper we compare data from both pieces of research to examine how competences developed during the undergraduate work placement contribute to the enhancement of graduate employment.

The role of the greens in the local politics of West Germany.

The study examines the contribution of the Greens to the changing nature of West Germany's local politics in the 1980s. The changes correspond broadly to the politicisation and parliamentarisation of a sphere of government traditionally perceived as being "unpolitical". Building upon theories of the New Politics, it is suggested that the varying pace of socio-economic change across the Federal Republic underlies the nonuniform development of its local party systems. The party systems of localities which have witnessed rapid social and economic change are found to be more susceptible to the emergence of a New Politics dimension than those of communities in which change has occurred less rapidly. The thesis continues by addressing aspects of the Greens' role in the development of local party systems across the Federal Republic. Despite the fact that marked differences in the Greens' approach to local political participation are registered in communities of varying socio-economic types, it is argued that the Greens are largely responsible for the introduction of a "New Local Politics" dimension into West Germany's local party systems. In a comprehensive study of the Greens' role in the Mainz party system, the conflicting styles and practices of the Greens and the established political parties in the city are depicted. The failure of the Green Party to form an alliance with the SPD in the city council is attributed to the cleavage between the Greens' New Politics and the SPD's Old Politics approaches. A detailed analysis of the parliamentary initiatives introduced by the four parties represented in the Mainz council between 1984 and 1987 also supports the contention that a New Politics dimension exists in the city's party system. This dimension is identified as representing a significant source of conflict during the period of analysis.

The central role of the neutrophil in ischaemic/reperfusion injury

Inadequate blood flow to an organ, ischaemia, may lead to both local and remote tissue injury characterized by oedema, increased microvascular permeability to protein and degradation of connective tissue components. This damage is probably caused by the accumulation and inappropriate activation of neutrophils which occurs when the tissue is reperfused. To test this hypothesis a number of in vitro models of the sequential stages of ischaemia/reperfusion injury were examined. Methods were initially developed to examine the adhesion of neutrophils to monolayers of a cultured endothelial cell line (ECV304) after periods of hypoxia and reoxygenation. Neutrophil migration in response to factors secreted by the treated endothelial cells was then assessed. The genesis of an inappropriate oxidative burst by the neutrophil upon exposure to endothelial chemoattractants and adhesion molecules was also measured. Finally to appraise how tissue function might be affected by endothelial cell hypoxia the contractility of vascular smooth muscle was examined. Neutrophil adhesion to ECV304 cells, which had been hypoxic for 4 hours and then reoxygenated for 30 minutes, was significantly increased. This response was probably initiated by reactive oxygen species (ROS) generated by the endothelial cells. Blockage of their production by allopurinol reduced the heightened adhesion. Similarly removal of ROS by superoxide dismutase or catalase also attenuated adhesion. ROS generation in turn caused the release of a soluble factor (s) which induced a conformational change on the neutrophil surface allowing it to bind to the intercellular adhesion molecule 1 (ICAM-1) on the endothelial cell. Soluble factor (s) from hypoxia/reoxygenated endothelial cells also had a powerful neutrophil chemoattractant ability. When neutrophils were exposed to both hypoxic/reoxygenated endothelial cells and the soluble factor (s) released by them a large oxidative burst was elicited. This response was greatest immediately after reoxygenation and one hour later was diminishing suggesting at least one of the components involved was labile. Analysis of the supernatant from hypoxic/reoxygenated endothelial cell cultures and studies using inhibitors of secretion suggested platelet activating factor (PAF) may be a major component in this overall sequence of events. Lesser roles for IL-8, TNF and LTB4 were also suggested. The secretory products from hypoxia/reoxygenated endothelial cells also affected smooth muscle contractility having an anti-vasoconstrictor or relaxation property, similar to that exerted by PAF.

A study of the role of the community pharmacist in responding to symptons

Factors affecting the current role of the community pharmacist in responding to symptoms are investigated. Communication and collaboration with general medical practitioners (GPs), and the competency of pharmacists and counter assistants to perform the role of responding to symptoms, are examined. A national survey of GPs, conducted by postal questionnaire, explores attitudes towards the role of the community pharmacist in the treatment of patients' symptoms, and towards future extension of such a role. A majority (over 90%) of respondents thought that the counter prescribing activities of the pharmacist should be maintained or increased. Doctors supported treatment of most minor illnesses by pharmacists, but there was relatively little support for the deregulation of selected Prescription Only Medicines. Three quarters of respondents were in favour of joint educational meetings for pharmacists and doctors. Most GPs (85%) expressed support for a formal referral route from pharmacists to doctors, using a "notification card". A pilot study of the use of a notification card was conducted . Two thirds of the patients who were advised to see their doctor by the pharmacist subsequently did so. In most cases , the GP rated the patients' symptoms " significant" and the card "helpful". Pharmacists' and counter assistants' competency in responding to symptoms was assessed by a programme of pharmacy visits, where previously-defined symptoms were presented. Some pharmacists' questioning skills were found to be inadequate, and their knowledge not sufficiently current. Counter assistants asked fewer and less appropriate questions than did pharmacists, and assistants ' knowledge base was shown to be inadequate. Recommendations are made in relation to the education and training of pharmacists and counter assistants in responding to symptoms .