Regulation of interleukin-8 from macrophages by acute hypoxia and hyperoxia : a role in the pathogenesis of the acute respiratory distress syndrome (ARDS)

The acute respiratory distress syndrome (ARDS) is a catastrophic form of acute lung inflammation. Patients with ARDS require support on the intensive care unit (ICU) and the associated mortality approaches 50%. ARDS represents the severe end of a spectrum of lung injury that evolves over a period of hours or days in a subgroup of patients following a major insult such as multiple trauma, sepsis or aspiration. Professor Haslett's group in Edinburgh have undertaken clinical studies in patients in the very early at-risk period of ARDS, soon after the initiating insult. We have shown that in patients with multiple trauma, raised levels of intrapulmonary interleukin-8 (IL-8), but not other inflammatory cytokines, are associated with subsequent progression to ARDS (n=56, P<0.001). IL-8 is a potent chemoattractant and activator of neutrophils, considered to be the primary injurious cell in ARDS. The high IL-8 levels were detected within a few hours (range 0.75 - 4 hr) of the trauma incident. Immunohistochemical analysis implicated the alveolar macrophage as a potent source of intrapulmonary IL-8. The mechanisms by which IL-8 may be rapidly generated in this clinical setting are unknown.Our clinical observations suggest that events occurring in the immediate aftermath of a trauma incident contribute to the generation of IL-8 in macrophages. I hypothesised that clinically relevant physiological events may include:1) A neuro-endocrine 'stress' response to major trauma. This would result in the rapid intrapulmonary and systemic release of clinically relevant stress mediators including catecholamines and neuropeptides that may stimulate the macrophage to generate IL8.1) A neuro-endocrine 'stress' response to major trauma. This would result in the rapid intrapulmonary and systemic release of clinically relevant stress mediators including catecholamines and neuropeptides that may stimulate the macrophage to generate IL8.2) Acute tissue hypoxia and hyperoxia. By the time of sampling, the trauma victims were likely to have undergone a period of sustained tissue hypoxia secondary to headinjury, atelectasis and lung contusion and subsequent resuscitation with delivery of high flow oxygen. I hypothesised that hypoxia / hyperoxia was as direct multiplestimuli or 'hits' to generate IL-8 in macrophages.I aimed to test these hypotheses in studies of cultured human monocyte-derived macrophages and in a novel animal model of acute lung injury.In human-monocyte derived macrophages, I have shown that the stress mediators adrenalin, substance P and macrophage migration inhibitory factor (MIF) do not increase IL-8 production at an early time-point (2 hr). Compared to normoxic controls, acute hypoxia (PO2 ~ 3.5 KPa) increased IL-8 protein release by 1.8-fold by 2 hours and steady-state IL-8 111RNA expression by 30 mins. The multiple hit of hypoxia / hyperoxia was found to be a more potent stimulus for IL-8 generation than hypoxia or hyperoxia alone.The effects of hypoxia / hyperoxia on IL-8 generation were studied in a rabbit model of acute lung injury. Localised bronchoscopic instillation of HC1 into the left lower lobe of an anaesthetised ventilated rabbit resulted in significantly increased IL-8 mRNA and protein expression, neutrophil infiltration into alveolar airspaces and lung in the directly injured lung but not the contralateral 'indirectly' injured lung. Systemic hypoxaemia was induced by reduction in the inspiratory oxygen fraction. Compared to normoxic controls III (arterial PaC>2 ~ 11 KPa), acute hypoxia (Pa02 ~ 5 KPa) for up to 2 hours increased intrapulmonary IL-8 mRNA but not protein expression in the acid-injured lung. Delivery of 100% oxygen for 2 hours (PaC>2 ~ 60 KPa) following acute hypoxia (a multiple-hit), increased both intrapulmonary IL-8 mRNA and IL-8 protein levels. The increase in IL-8 protein was attenuated if the reoxygenation phase was controlled to return arterial PO2 to normoxic levels (-11 KPa).The mechanisms by which hypoxia may rapidly increase IL-8 mRNA expression in monocyte-derived macrophages was further studied in vitro. The rapidity of the response (30 mins) suggested an increase in gene transcription. Electromobility gel-shift assay revealed that hypoxia increased nuclear levels of the IL-8 promoter-binding transcription factors AP-1 and CEBP-P, but not NF-kB, by 15 min exposure. Hypoxia induced macrophage expression of HIF-la, a critical regulator of hypoxic adaptive responses. However cobalt chloride and desferrioxamine, HIF-la-inducing hypoxia mimics, did not upregulate IL-8, suggesting that IL-8 transcription may be HIF-1 independent. Finally it was demonstrated that in contrast to IL-8, hypoxia inhibited expression of a panel of chemokines and cytokines including MCP-1, MlP-la, MIP-ip and TNF-a. Both the pattern of chemokine expression and transcription factor activation with hypoxia differed from that induced by bacterial lipopolysaccharide (LPS), which potently activated NF-kB and upregulated several inflammatory genes.These data support the hypothesis that acute hypoxia / hyperoxia act as multiple-hits in the generation of macrophage-derived IL-8 in vitro and intrapulmonary IL-8 in vivo, representing a potential mechanism for our observation of elevated alveolar IL-8 levels patients with multiple trauma that progress to ARDS. The observation that hypoxia alone rapidly and selectively increased IL-8 mRNA expression suggests that hypoxia may represent a 'priming' stimulus in macrophages, 'arming' the cell for a subsequent second hit such as hyperoxia. Furthermore, the specific chemokine response to hypoxia differs markedly with that observed with LPS implying potentially distinct adaptive responses to hypoxia and infection in the macrophage

Planning and multiculturalism: A paradigm shift.

Social theorists as diverse as Durkheim, Weber and Marx argued that, as a concomitant of the 19th century emergence of modern industrial society, ethnic groups had lost their saliency in the lives of individuals'1. Policy-makers too believed that assimilation of the ethnic minority was a way forward and inevitable. This view was compounded by the idea typified in the 'global village' scenario brought out by the technological revolution. 'Transnational migrations, post-colonialism, and the rise of civil society' (Sandercock, 2000) has made the 21st century indisputably the century of multicultural cities which have brought about enormous socio-cultural changes. In 2000, between 150 & 175 million people lived outside the country in which they were born and Inglis (1996) points out that only 10 to 15 percent of countries can be reasonably described as ethnically homogenous. This has resulted in an increased ethnic and cultural diversity of cities and has led to co existence side by side of 'dissimilar ways of life within the sphere of the world's main metropolitan areas' (Sandercock, 2000). Furthermore, the second and third generations of the settled immigrants - the Diasporas, the Internet and globalisation has led to fast shifting boundaries of social identity, which has in turn led to infinite number of sub cultures. The rediscovery of ethnicity and conflicts brought about as a result of unresolved underlying differences has made decision makers increasingly aware of the need to develop policies which will contribute to the development of harmonious relations within and between diverse ethnic groups. Rapid advancements in technology has enabled us to interact socially, politically and economically with other nations and has gone a long way towards breaking the barriers that kept us apart from one another, allowing corporations to ignore the national boundaries and create networks that disregard politics. However as Schwetz (2004) argue, social understanding of the diversity of this world has not caught up with this technological interconnectivity. He concludes that cultural education is far behind the trend towards globalisation. How can diversity be accepted and incorporated into a practice that is equitable and willing to accommodate different ways of dwelling in urban space and how does local government respond to a diverse community, ensuring that all services and processes are accessible by all To what extent planners can be said to have an awareness of racial disadvantage and its possible implications for planning Planners are struggling to find answers to these questions which present relentless challenges. This is made even more difficult when one considers the unrecorded or unspoken beckoning and nuances that have to be dealt with - for example, Qadeer (1997) recalls an story where the newspaper headlines in The Globe and Mail read: "nature meets culture" - 'Italians and Portuguese like to keep trees short, allowing a better view of the neighbours. Anglo-Saxons want trees to be tall and leafy, blocking any views from and to neighbourhood houses. The Chinese believe trees in front of a home bring bad luck. As if these different preferences were not enough, the city has strict bylaws that prohibit cutting down trees....' or for example, The Guardian Newspaper reported, 'beckoning to a Somali is very offensive... it is like calling someone a dog - one can just imagine how a friendly bobby's curling finger could seem to a Somali youth' . This thesis argue that in order to grapple with these realities at the neighbourhood level in order to strive to achieve sustainable communities, planners will need to understand the wider social, ethnic and cultural 'histories' and 'stories' and to have a better and deeper understanding of the culture specificities intrinsic to every ethno-cultural community - a knowledge of their 'way of life': customs, faiths, and convention codes of manners, dress, cuisine, language, arts, science, technology, religion and rituals norms and regulations of behaviour, traditions and institutions.4 White Papers during the last decade have been informed by the government's desire of a non-racist and multicultural Britain. ODPM (2005) reminds the planners that planning is now operating within a different context than was the case in the past. Thus if the government's vision for Britain, 'where cultural, demographic and social diversity are respected and celebrated where discrimination is tackled robustly where different communities co-exit in mutual respect and understanding and where attitudes that block the progress of individuals and groups are tackled'5 was ever to become a reality then social disadvantage or discrimination related to ethnicity and to land use planning must be recognised and acted upon as otherwise they will remain just rhetorical and aspirational, or in Mitchell's words remain a 'liberal fantasy'

Knowledge, attitudes and practices of medical staff towards obesity management in patients with spinal cord injuries: an International survey of four western European countries

Objective: To (1) examine the opinions of medical staff working in spinal cord injury (SCI) centres (SCICs); (2) evaluate their knowledge, attitudes and practices towards obesity prevention and management; (3) report the number of beds and dietitians available at each SCIC. Methods: A 37-item questionnaire was sent to 23 SCICs in the UK, the Netherlands, Belgium and the Republic of Ireland between September 2012 and January 2013. Results: Eighteen SCICs returned the questionnaires for analysis. All respondents stated that they had an interest in obesity treatment but only 2.3% of the respondents received training in obesity management. Sixty-one percent of staff did not consider body mass index (BMI) to be appropriate for use in SCI patients and subsequently less than half of the respondents use BMI routinely. The majority of respondents reported that they are confident in dealing with overweight (74.5%) and obese (66.1%) SCI adults, less than half (44.1%) are confident in treating overweight and obese SCI children. Respondents also indicated the need for nationally adopted guidelines and a lack of physical activity provision. There were 17.5 whole-time equivalent (WTE) dietitians recorded in 22 SCICs, equivalent to 47.8 beds per WTE dietitians (range 10–420). Non-UK SCIC dietitians are significantly better resourced than in UK SCICs (beds per WTE dietitian: 36 vs 124, P=0.035). Conclusion: Medical staff expressed the need to participate in obesity prevention and management. Appropriate training should be considered for all medical staff and the development of specific weight management guidelines and dietetic provision should be considered

Asp295 Stabilizes the Active-Site Loop Structure of Pyruvate Dehydrogenase, Facilitating Phosphorylation of Ser292 by Pyruvate Dehydrogenase-Kinase

We have developed an in vitro system for detailed analysis of reversible phosphorylation of the plant mitochondrial pyruvate dehydrogenase complex, comprising recombinant Arabidopsis thalianaα2β2-heterotetrameric pyruvate dehydrogenase (E1) plus A. thaliana E1-kinase (AtPDK). Upon addition of MgATP, Ser292, which is located within the active-site loop structure of E1α, is phosphorylated. In addition to Ser292, Asp295 and Gly297 are highly conserved in the E1α active-site loop sequences. Mutation of Asp295 to Ala, Asn, or Leu greatly reduced phosphorylation of Ser292, while mutation of Gly297 had relatively little effect. Quantitative two-hybrid analysis was used to show that mutation of Asp295 did not substantially affect binding of AtPDK to E1α. When using pyruvate as a variable substrate, the Asp295 mutant proteins had modest changes in kcat, Km, and kcat/Km values. Therefore, we propose that Asp295 plays an important role in stabilizing the active-site loop structure, facilitating transfer of the γ-phosphate from ATP to the Ser residue at regulatory site one of E1α

In-home dementia caregiving is associated with greater psychological burden and poorer mental health than out-of-home caregiving: a cross-sectional study

Introduction: Caregivers who live with a person with dementia who receives care, compared with those who live elsewhere, are often considered to experience greater levels of psychological and affective burden. The evidence for this is, however, only limited to studies employing small sample sizes and that failed to examine caregivers’ psychological wellbeing. We address these issues in a large cohort of dementia caregivers. // Methods: We conducted a cross-sectional study comparing caregivers living with a dementia care recipient (n = 240) to caregivers living elsewhere (n = 255) on caregivers’ burden, anxiety, and depression. // Results: We found that caregivers living with the care recipient relative to those living elsewhere showed significantly greater burden and depression, but we found no group difference in anxiety. // Conclusions: Our study adds to the evidence by showing that cohabiting with a care recipient with dementia is associated with greater burden and poorer psychological wellbeing. Strategies aiming to improve caregivers’ burden and psychological wellbeing should take account of caregivers’ living arrangements

SOlution Focused brief therapy In post-stroke Aphasia (SOFIA Trial): protocol for a feasibility randomised controlled trial

Background: Around a quarter of people post stroke will experience aphasia, a language disability. Having aphasia places someone at risk of becoming depressed and isolated. There is limited evidence for effective interventions to enhance psychological well-being for this client group. A potential intervention is Solution Focused Brief Therapy (SFBT), which supports a person to build meaningful, achievable change through focusing on a person’s skills and resources rather than their deficits. The SOFIA Trial aims to explore the acceptability of SFBT to people with varying presentations of aphasia, including severe aphasia, and to assess the feasibility of conducting a future definitive trial investigating clinical and cost effectiveness. Methods: The trial is a single-blind, randomised, wait-list controlled feasibility trial with nested qualitative research and pilot economic evaluation comparing SFBT plus usual care to usual care alone. The study will recruit 32 participants with aphasia who are ≥6 months post stroke. All participants will be assessed on psychosocial outcome measures at baseline, then at three and six months post randomisation by assessors blinded to treatment allocation. Participants will be randomly assigned to intervention group (start intervention immediately post randomisation) or wait-list group (start intervention six months post randomisation). Wait-list group will additionally be assessed nine months post randomisation. The intervention consists of up to six SFBT sessions delivered over three months by speech and language therapists. Participants and therapists will also take part in in-depth interviews exploring their experiences of the study. The pilot economic evaluation will use the EQ-5D-5L measure and an adapted Client Service Receipt Inventory. People with aphasia have been involved in designing and monitoring the trial. Discussion: Given the high levels of depression and isolation, there is a need to investigate effective interventions that enhance the psychological wellbeing of people with aphasia. Trial registration: ClinicalTrials.gov NCT03245060. 10/08/2017

Major role of pKpQIL-like plasmids in the early dissemination of KPC-type carbapenemases in the UK

Objectives: KPC-producing Enterobacteriaceae were first seen in the UK in 2003 and have been increasingly reported since 2010, largely owing to an ongoing outbreak in North-West England. We examined the role of clonal spread and plasmid transmission in their emergence. Methods: Isolates comprised KPC-positive Klebsiella pneumoniae (n=33), Escherichia coli (n=7) and Enterobacter spp. (n=4) referred to the national reference laboratory between 2008 and 2010 from 17 UK centres, including three in North-West England. Isolates were typed by MLST. Plasmids were transferred by electroporation and characterised by PCR or sequencing. PCR screening assays were developed to distinguish plasmid pKpQIL variants. Results: The K. pneumoniae isolates included 10 STs, of which three belonged to clonal group (CG) 258. CG258 (n=19) isolates were detected in 13 centres but accounted for only 7/19 (36.8%) of those from North-West England. Most KPC-producers (37/44, 84.1%), including 16/19 CG258 K. pneumoniae carried blaKPC on IncFIIK2 plasmids. Sequencing of a subset of these plasmids (n=11) revealed similarities with published pKpQIL. One variant, pKpQIL-UK - identified in K. pneumoniae CG258 (n=5) and ST468 (n=1) isolates from distinct centres - had only a few nucleotide changes from classical pKpQIL, whereas pKpQIL-D1 (n=1) and pKpQIL-D2 (n=4), from isolates of various species in the North-West, harboured large variations reflecting replacement of the partitioning and replication functions and potentially thereby facilitating spread. PCR revealed that 36/37 (97.3%) IncFIIK2-type plasmids in KPC-positive isolates had pKpQIL markers. Conclusions: pKpQIL-like plasmids played a major role in the early dissemination of KPC enzymes in the UK

Foundation relative stiffness effects in sand under static loading

In the geotechnical engineering applications, precise understandings are yet to be established on the effects of a foundation stiffness on its bearing capacity and settlement. The modern foundation construction uses the new available construction materials that totally change the relative stiffness of the footing structures–soil interactions such as waste material and landfill area of more residential purposes. Conventional bearing capacity equations were dealt with common rigid footing and thus cannot be used for reduced foundation rigidity. Therefore, this study investigates the effects of foundation relative stiffness on its load-displacement behaviour and the soil deformation field using compression test of a strip smooth footings on surface of sand of different packing densities. Nine experimental tests using three footing materials (plastic (P), rubber (R) and aluminium (A)) that differ in relative stiffness with three soil densities were used. This study has separated the effects of relative stiffness of the foundation systems on bearing capacity and settlement by defining the failure mechanism using digital particle image velocimetry (DPIV). The bearing capacity decreases as the foundation system stiffness increases. This decrease, however, is also associated with a smaller ultimate settlement. It is also apparent that a clear trend can be observed in dimensions of the slip surface when comparing rigid and flexible foundation systems. The soil particles in the failure zone under the footing have the highest vertical displacement for the increase in the rigidity of the footing system. A change in the relative stiffness of a foundation system affects the deformation of a granular media and particular analyses have been taken into the load-displacement behaviour, failure mechanisms and velocity fields