Phenotypic characteristics contributing to the enhanced growth of Escherichia coli bloom strains

During bloom events, Escherichia coli cell counts increase to between 10,000 and 100,000 cfu/100 ml of water. The strains responsible for bloom events belong to E. coli phylogenetic groups A and B1, and all have acquired a capsule from Klebsiella. A pan‐genome comparison of phylogroup A E. coli revealed that the ferric citrate uptake system (fecIRABCDE) was overrepresented in phylogroup A bloom strains compared with non‐bloom E. coli. A series of experiments were carried out to investigate if the capsule together with ferric citrate uptake system could confer a growth rate advantage on E. coli. Capsulated strains had a growth rate advantage regardless of the media composition and the presence/absence of the fec operon, and they had a shorter lag phase compared with capsule‐negative strains. The results suggest that the Klebsiella capsule may facilitate nutrient uptake or utilization by a strain. This, together with the protective roles played by the capsule and the shorter lag phase of capsule‐positive strains, may explain why it is only capsule‐positive strains that produce elevated counts in response to nutrient influx

Reacción en el tamaño de poliquetos del fondo marino frente a diferentes regímenes nutricionales

Analyses of body size of abyssal polychaetes were made from sites experiencing different levels of nutrient flux in the Pacific and Atlantic Oceans. Measuring polychaetes was problematical due to high levels of fragmentation, and width of the first chaetiger was used as a surrogate for body size. Results indicated that polychaetes were significantly smaller in Atlantic areas experiencing seasonal or periodic input of phytodetritus. This observation held not just for comparison of sizes of the total assemblage but also when comparisons were made at the family and species level. Not all families showed a response. In the Atlantic, individuals belonging to the families Cirratulidae, Spionidae and Sabellidae indicated size differences, while in the Pacific spionids were significantly smaller from phytodetrital sites. At the species level, six species - all deposit feeders - were significantly smaller from phytodetrital sites, while two nominally predator/omnivore species showed an increase in size. Two hypotheses for the size frequency of the Atlantic populations from phytodetrital sites are suggested – the juvenile recruitment hypothesis where the smaller population body size is because of an influx of newly recruited juveniles; and the allometric plasticity hypothesis which postulates a physiological response from populations from non-phytodetrital areas delaying reproduction and putting more energy into growth, hence resulting in a larger body size. It is hypothesised that the larger size in non-phytodetrital sites may be a response to starvation.Se han realizado análisis sobre el tamaño de algunos poliquetos de zonas abisales marinas con diferentes niveles de flujo de nutrientes en los océanos Atlántico y Pacífico. Dada la tendencia a romperse, la medición de dichos poliquetos fué problemática. Por esta razon, la anchura del primer chaetígero se ha tomado como sustituto del tamaño total. Los resultados indican que los poliquetos eran notablemente más pequeños en zonas donde el flujo de nutrientes era estacional u ocasional. Ésta observación no solo se aplica a la totalidad de la población, sino también al nivel taxonómico familiar y por especies. No todas las familias mostraron dicha relación. En el océano Atlántico, individuos pertenecientes a las familias Cirratulidae, Spionidae y Sabellidae mostraron diferencias de tamaño, mientras que en el océano Pacífico las familias Paraonidae y Spionidae eran de menor tamaño en zonas con aportación nutritiva. Al nivel de especie, seis especies, todas ellas detritívoras, eran más pequeñas en zonas con flujo de nutrientes, y otras dos especies, ambas consideradas carnívoras/omnívoras, eran más grandes en dichas donas. Un análisis de frecuencia de los distintos tamaños de poliquetos en estas zonas demuestran que el alto numero de tamaños menores no ha sido causado por una afluencia de juveniles. Se especula que el mayor tamaño de poliquetos encontrados en zonas con flujo de nutrientes estacional se debe a una reacción de inanición. &nbsp

Using comprehensive geriatric assessment for quality improvements in healthcare of older people in UK care homes: protocol for realist review within Proactive Healthcare of Older People in Care Homes (PEACH) study

Introduction Care home residents are relatively high users of healthcare resources and may have complex needs. Comprehensive geriatric assessment (CGA) may benefit care home residents and improve efficiency of care delivery. This is an approach to care in which there is a thorough multidisciplinary assessment (physical and mental health, functioning and physical and social environments) and a care plan based on this assessment, usually delivered by a multidisciplinary team. The CGA process is known to improve outcomes for community-dwelling older people and those in receipt of hospital care, but less is known about its efficacy in care home residents. Methods and analysis Realist review was selected as the most appropriate method to explore the complex nature of the care home setting and multidisciplinary delivery of care. The aim of the realist review is to identify and characterise a programme theory that underpins the CGA intervention. The realist review will extract data from research articles which describe the causal mechanisms through which the practice of CGA generates outcomes. The focus of the intervention is care homes, and the outcomes of interest are health-related quality of life and satisfaction with services; for both residents and staff. Further outcomes may include appropriate use of National Health Service services and resources of older care home residents. The review will proceed through three stages: (1) identifying the candidate programme theories that underpin CGA through interviews with key stakeholders, systematic search of the peer-reviewed and non-peer-reviewed evidence, (2) identifying the evidence relevant to CGA in UK care homes and refining the programme theories through refining and iterating the systematic search, lateral searches and seeking further information from study authors and (3) analysis and synthesis of evidence, involving the testing of the programme theories. Ethics and dissemination The PEACH project was identified as service development following submission to the UK Health Research Authority and subsequent review by the University of Nottingham Research Ethics Committee. The study protocols have been reviewed as part of good governance by the Nottinghamshire Healthcare Foundation Trust. We aim to publish this realist review in a peer-reviewed journal with international readership. We will disseminate findings to public and stakeholders using knowledge mobilisation techniques. Stakeholders will include the Quality Improvement Collaboratives within PEACH study. National networks, such as British Society of Gerontology and National Care Association will be approached for wider dissemination

Inter-annual species-level variations in an abyssal polychaete assemblage (Sta. M, NE Pacific, 4000 m)

Understanding the dynamics of abyssal community structure and function has become increasingly important as deep-sea resource exploitation and climate change pressures are expected to ramp up. This time-series study investigates macrofaunal polychaete dynamics at a station in the North East Pacific (Sta. M; 35˚ N 123˚ W, 4000 m, 1991-2011). Infaunal polychaete species were identified and their proxy biomass and proxy energy use rate estimated. The assemblage comprised 167 species, having a composition consistent with other abyssal areas globally. Significant changes in univariate and multivariate parameters (rank abundance distribution, Simpson’s diversity index, and species and functional group composition) were detected across 1991-2011. However, no change in biomass or energy use rate was apparent through the time-series. The largest changes in the polychaete assemblage coincided with both an increase in sinking particulate organic carbon flux to the seafloor in 2007, and a 40 km relocation of the sampling location to a site 100 m shallower, preventing a conclusive assessment of which might drive the observed variation. Analyses prior to the change of sampling location showed that the polychaete assemblage composition dynamics were primary driven by food supply variation. Changes in several species were also lagged to changes in POC flux by 4 to 10 months. The polychaete fauna exhibited a significant positive relationship between total density and total energy use rate, suggesting population-level tracking of a common resource (e.g. POC flux food supply). Neither compensatory nor energetic zero-sum dynamics were detected among the polychaete assemblage, but the results suggest that the latter occur in the macrofaunal community as a whole. The results do indicate (a) potential control of species composition, and the density of individual key species, by food supply, when the time-series prior to the sampling location was analysed separately, and (b) generally sensitive detection of environmental change by species-level analysis of the abyssal polychaete assemblage

Heart Rate Variability Measurement and Clinical Depression in Acute Coronary Syndrome Patients: Narrative Review of Recent Literature

Aim: We aimed to explore links between heart rate variability (HRV) and clinical depression in patients with acute coronary syndrome (ACS), through a review of recent clinical research literature. Background: Patients with ACS are at risk for both cardiac autonomic dysfunction and clinical depression. Both conditions can negatively impact the ability to recover from an acute physiological insult, such as unstable angina or myocardial infarction, increasing the risk for adverse cardiovascular outcomes. HRV is recognized as a reflection of autonomic function. Methods: A narrative review was undertaken to evaluate state-of-the-art clinical research, using the PubMed database, January 2013. The search terms “heart rate variability” and “depression” were used in conjunction with “acute coronary syndrome”, “unstable angina”, or “myocardial infarction” to find clinical studies published within the past 10 years related to HRV and clinical depression, in patients with an ACS episode. Studies were included if HRV measurement and depression screening were undertaken during an ACS hospitalization or within 2 months of hospital discharge. Results: Nine clinical studies met the inclusion criteria. The studies’ results indicate that there may be a relationship between abnormal HRV and clinical depression when assessed early after an ACS event, offering the possibility that these risk factors play a modest role in patient outcomes. Conclusion: While a definitive conclusion about the relevance of HRV and clinical depression measurement in ACS patients would be premature, the literature suggests that these measures may provide additional information in risk assessment. Potential avenues for further research are proposed

Comparative genomics of Crohn's disease-associated adherent-invasive Escherichia coli

OBJECTIVE Adherent-invasive Escherichia coli (AIEC) are a leading candidate bacterial trigger for Crohn's disease (CD). The AIEC pathovar is defined by in vitro cell-line assays examining specific bacteria/cell interactions. No molecular marker exists for their identification. Our aim was to identify a molecular property common to the AIEC phenotype. DESIGN 41 B2 phylogroup E. coli strains were isolated from 36 Australian subjects: 19 patients with IBD and 17 without. Adherence/invasion assays were conducted using the I-407 epithelial cell line and survival/replication assays using the THP-1 macrophage cell line. Cytokine secretion tumour necrosis factor ((TNF)-α, interleukin (IL) 6, IL-8 and IL-10) was measured using ELISA. The genomes were assembled and annotated, and cluster analysis performed using CD-HIT. The resulting matrices were analysed to identify genes unique/more frequent in AIEC strains compared with non-AIEC strains. Base composition differences and clustered regularly interspaced palindromic repeat (CRISPR) analyses were conducted. RESULTS Of all B2 phylogroup strains assessed, 79% could survive and replicate in macrophages. Among them, 11/41 strains (5 CD, 2 UCs, 5 non-IBD) also adhere to and invade epithelial cells, a phenotype assigning them to the AIEC pathovar. The AIEC strains were phylogenetically heterogeneous. We did not identify a gene (or nucleic acid base composition differences) common to all, or the majority of, AIEC. Cytokine secretion and CRISPRs were not associated with the AIEC phenotype. CONCLUSIONS Comparative genomic analysis of AIEC and non-AIEC strains did not identify a molecular property exclusive to the AIEC phenotype. We recommend a broader approach to the identification of the bacteria-host interactions that are important in the pathogenesis of Crohn's disease.This research was supported by an Australian Academy of Science France-Australia Science Innovation Collaboration early career fellowship; a Gastroenterological Society of Australia (GESA) Clinical Research grant; and funding from the Ministère de la Recherche et de la Technologie, Inserm (UMR1071), INRA (USC-2018); and Nouveau Chercheur EPST from Conseil Régional Auvergne

Provision of NHS generalist and specialist services to care homes in England: review of surveys

Background: The number of beds in care homes (with and without nurses) in the United Kingdom is three times greater than the number of beds in National Health Service (NHS) hospitals. Care homes are predominantly owned by a range of commercial, not-for-profit or charitable providers and their residents have high levels of disability, frailty and co-morbidity. NHS support for care home residents is very variable, and it is unclear what models of clinical support work and are cost-effective. Objectives: To critically evaluate how the NHS works with care homes.MethodsA review of surveys of NHS services provided to care homes that had been completed since 2008. It included published national surveys, local surveys commissioned by Primary Care organisations, studies from charities and academic centres, grey literature identified across the nine government regions, and information from care home, primary care and other research networks. Data extraction captured forms of NHS service provision for care homes in England in terms of frequency, location, focus and purpose. Results: Five surveys focused primarily on general practitioner services, and 10 on specialist services to care home. Working relationships between the NHS and care homes lack structure and purpose and have generally evolved locally. There are wide variations in provision of both generalist and specialist healthcare services to care homes. Larger care home chains may take a systematic approach to both organising access to NHS generalist and specialist services, and to supplementing gaps with in-house provision. Access to dental care for care home residents appears to be particularly deficient. Conclusions:Historical differences in innovation and provision of NHS services, the complexities of collaborating across different sectors (private and public, health and social care, general and mental health), and variable levels of organisation of care homes, all lead to persistent and embedded inequity in the distribution of NHS resources to this population. Clinical commissioners seeking to improve the quality of care of care home residents need to consider how best to provide fair access to health care for older people living in a care home, and to establish a specification for service delivery to this vulnerable population

GPs’ involvement to improve care quality in care homes in the UK: a realist review

BackgroundOrganising health-care services for residents living in care homes is an important area of development in the UK and elsewhere. Medical care is provided by general practitioners in the UK, and the unique arrangement of the NHS means that general practitioners are also gatekeepers to other health services. Despite recent focus on improving health care for residents, there is a lack of knowledge about the role of general practitioners.ObjectivesFirst, to review reports of research and quality improvement (or similar change management) in care homes to explore how general practitioners have been involved. Second, to develop programme theories explaining the role of general practitioners in improvement initiatives and outcomes.DesignA realist review was selected to address the complexity of integration of general practice and care homes.SettingCare homes for older people in the UK, including residential and nursing homes.ParticipantsThe focus of the literature review was the general practitioner, along with care home staff and other members of multidisciplinary teams. Alongside the literature, we interviewed general practitioners and held consultations with a Context Expert Group, including a care home representative.InterventionsThe primary search did not specify interventions, but captured the range of interventions reported. Secondary searches focused on medication review and end-of-life care because these interventions have described general practitioner involvement.OutcomesWe sought to capture processes or indicators of good-quality care.Data sourcesSources were academic databases [including MEDLINE, EMBASE™ (Elsevier, Amsterdam, the Netherlands), Cumulative Index to Nursing and Allied Health Literature, PsycInfo® (American Psychological Association, Washington, DC, USA), Web of Science™ (Clarivate Analytics, Philadelphia, PA, USA) and Cochrane Collaboration] and grey literature using Google Scholar (Google Inc., Mountain View, CA, USA).MethodsRealist And Meta-narrative Evidence Syntheses: Evolving Standards (RAMESES) guidelines were followed, comprising literature scoping, interviews with general practitioners, iterative searches of academic databases and grey literature, and synthesis and development of overarching programme theories.ResultsScoping indicated the distinctiveness of the health and care system in UK and, because quality improvement is context dependent, we decided to focus on UK studies because of potential problems in synthesising across diverse systems. Searches identified 73 articles, of which 43 were excluded. To summarise analysis, programme theory 1 was ‘negotiated working with general practitioners’ where other members of the multidisciplinary team led initiatives and general practitioners provided support with the parts of improvement where their skills as primary care doctors were specifically required. Negotiation enabled matching of the diverse ways of working of general practitioners with diverse care home organisations. We found evidence that this could result in improvements in prescribing and end-of-life care for residents. Programme theory 2 included national or regional programmes that included clearly specified roles for general practitioners. This provided clarity of expectation, but the role that general practitioners actually played in delivery was not clear.LimitationsOne reviewer screened all search results, but two reviewers conducted selection and data extraction steps.ConclusionsIf local quality improvement initiatives were flexible, then they could be used to negotiate to build a trusting relationship with general practitioners, with evidence from specific examples, and this could improve prescribing and end-of-life care for residents. Larger improvement programmes aimed to define working patterns and build suitable capacity in care homes, but there was little evidence about the extent of local general practitioner involvement.Future workFuture work should describe the specific role, capacity and expertise of general practitioners, as well as the diversity of relationships between general practitioners and care homes.Study registrationThis study is registered as PROSPERO CRD42019137090