Ustekinumab as induction and maintenance therapy for ulcerative colitis - national extended follow-up and a review of the literature

INTRODUCTION

Ustekinumab use in ulcerative colitis had shown low adverse event and high persistence rates to 3 years via the UNIFI long-term extension study. Outcomes beyond 3 years have not been previously described. We describe the safety signals of the entire UNIFI Australian population beyond 3 years.

METHODS

This retrospective multicenter observational cohort study recruited from all Australian UNIFI centers. The primary outcome was safety via adverse events. Secondary outcomes included the clinical relapse rate on ustekinumab, and the need to switch from ustekinumab to an alternate agent.

RESULTS

There were 14 patients [11 male, mean age 47 (±14) years], with a median diagnosis of 10.8 (±4.5) years prior to UNIFI enrollment. Median follow-up was 298 weeks (5.7 years) (Interquartile range (IQR): 220-311 weeks). Within the long-term extension, there were three serious adverse events and one minor event. 42.9% (6/14) patients had clinical relapses, of which clinical remission was recaptured in 83.3% (5/6). 85.7% (12/14) persisted on ustekinumab in the long-term, with 7.1% (1/14) electively ceasing ustekinumab and 7.1% (1/14) changed from ustekinumab due to clinical relapse.

CONCLUSION

For moderate-to-severe UC in Australia, ustekinumab maintained efficacy beyond 3 years with a high persistence rate and no new safety signals.

TRIAL REGISTRATION

The trial is registered at ANZCTR (identifier: ACTRN12622001332718).

A secreted bacterial protein protects bacteria from cationic antimicrobial peptides by entrapment in phase-separated droplets

Mammalian hosts combat bacterial infections through the production of defensive cationic antimicrobial peptides (CAPs). These immune factors are capable of directly killing bacterial invaders; however, many pathogens have evolved resistance evasion mechanisms such as cell surface modification, CAP sequestration, degradation, or efflux. We have discovered that several pathogenic and commensal proteobacteria, including the urgent human threat Neisseria gonorrhoeae, secrete a protein (lactoferrin-binding protein B, LbpB) that contains a low-complexity anionic domain capable of inhibiting the antimicrobial activity of host CAPs. This study focuses on a cattle pathogen, Moraxella bovis, that expresses the largest anionic domain of the LbpB homologs. We used an exhaustive biophysical approach employing circular dichroism, biolayer interferometry, cross-linking mass spectrometry, microscopy, size-exclusion chromatography with multi-angle light scattering coupled to small-angle X-ray scattering (SEC-MALS-SAXS), and NMR to understand the mechanisms of LbpB-mediated protection against CAPs. We found that the anionic domain of this LbpB displays an α-helical secondary structure but lacks a rigid tertiary fold. The addition of antimicrobial peptides derived from lactoferrin (i.e. lactoferricin) to the anionic domain of LbpB or full-length LbpB results in the formation of phase-separated droplets of LbpB together with the antimicrobial peptides. The droplets displayed a low rate of diffusion, suggesting that CAPs become trapped inside and are no longer able to kill bacteria. Our data suggest that pathogens, like M. bovis, leverage anionic intrinsically disordered domains for the broad recognition and neutralization of antimicrobials via the formation of biomolecular condensates.

WITHDRAWN: Evaluation of Fourier Transform Infrared spectroscopy (IR Biotyper) as a complement to Whole genome sequencing (WGS) to characterise Enterobacter cloacae , Citrobacter freundii and Klebsiella pneumoniae isolates recovered from hospital sinks

The authors have withdrawn their manuscript due to becoming aware of methodology issues related to the curation of the training set used to determine cut-off values for Biotyper cluster assignation and lack of replicate measurements on different days for the isolates analysed. It is therefore unclear whether the conclusions of the manuscript are founded and no further work is possible to correct these issues as the instrument is no longer available to the authors. If you have any questions, please contact the corresponding author.

A workflow for the detection of antibiotic residues, measurement of water chemistry and preservation of hospital sink drain samples for metagenomic sequencing

BACKGROUND

Hospital sinks are environmental reservoirs that harbour healthcare-associated (HCA) pathogens. Selective pressures in sink environments, such as antibiotic residues, nutrient waste and hardness ions, may promote antibiotic resistance gene (ARG) exchange between bacteria. However, cheap and accurate sampling methods to characterize these factors are lacking.

AIMS

To validate a workflow to detect antibiotic residues and evaluate water chemistry using dipsticks. Secondarily, to validate boric acid to preserve the taxonomic and ARG ('resistome') composition of sink trap samples for metagenomic sequencing.

METHODS

Antibiotic residue dipsticks were validated against serial dilutions of ampicillin, doxycycline, sulfamethoxazole and ciprofloxacin, and water chemistry dipsticks against serial dilutions of chemical calibration standards. Sink trap aspirates were used for a 'real-world' pilot evaluation of dipsticks. To assess boric acid as a preservative of microbial diversity, the impact of incubation with and without boric acid at ∼22 °C on metagenomic sequencing outputs was evaluated at Day 2 and Day 5 compared with baseline (Day 0).

FINDINGS

The limits of detection for each antibiotic were: 3 μg/L (ampicillin), 10 μg/L (doxycycline), 20 μg/L (sulfamethoxazole) and 8 μg/L (ciprofloxacin). The best performing water chemistry dipstick correctly characterized 34/40 (85%) standards in a concentration-dependent manner. One trap sample tested positive for the presence of tetracyclines and sulphonamides. Taxonomic and resistome composition were largely maintained after storage with boric acid at ∼22 °C for up to five days.

CONCLUSIONS

Dipsticks can be used to detect antibiotic residues and characterize water chemistry in sink trap samples. Boric acid was an effective preservative of trap sample composition, representing a low-cost alternative to cold-chain transport.

PARP1 condensates differentially partition DNA repair proteins and enhance DNA ligation

Poly(ADP-ribose) polymerase 1 (PARP1) is one of the first responders to DNA damage and plays crucial roles in recruiting DNA repair proteins through its activity - poly(ADP-ribosyl)ation (PARylation). The enrichment of DNA repair proteins at sites of DNA damage has been described as the formation of a biomolecular condensate. However, it is not understood how PARP1 and PARylation contribute to the formation and organization of DNA repair condensates. Using recombinant human PARP1 in vitro, we find that PARP1 readily forms viscous biomolecular condensates in a DNA-dependent manner and that this depends on its three zinc finger (ZnF) domains. PARylation enhances PARP1 condensation in a PAR chain-length dependent manner and increases the internal dynamics of PARP1 condensates. DNA and single-strand break repair proteins XRCC1, LigIII, Polβ, and FUS partition in PARP1 condensates, although in different patterns. While Polβ and FUS are both homogeneously mixed within PARP1 condensates, FUS enrichment is greatly enhanced upon PARylation whereas Polβ partitioning is not. XRCC1 and LigIII display an inhomogeneous organization within PARP1 condensates; their enrichment in these multiphase condensates is enhanced by PARylation. Functionally, PARP1 condensates concentrate short DNA fragments and facilitate compaction of long DNA and bridge DNA ends. Furthermore, the presence of PARP1 condensates significantly promotes DNA ligation upon PARylation. These findings provide insight into how PARP1 condensation and PARylation regulate the assembly and biochemical activities in DNA repair foci, which may inform on how PARPs function in other PAR-driven condensates.

Detection, survival, and persistence of Staphylococcus capitis NRCS-A in neonatal units in England

BACKGROUND

The multidrug-resistant Staphylococcus capitis clone, NRCS-A, is increasingly associated with late-onset sepsis in low birthweight newborns in neonatal intensive care units (NICUs) in England and globally. Understanding where this bacterium survives and persists within the NICU environment is key to developing and implementing effective control measures.

AIM

To investigate the potential for S. capitis to colonize surfaces within NICUs.

METHODS

Surface swabs were collected from four NICUs with and without known NRCS-A colonizations/infections present at the time of sampling. Samples were cultured and S. capitis isolates analysed via whole-genome sequencing. Survival of NRCS-A on plastic surfaces was assessed over time and compared to that of non-NRCS-A isolates. The bactericidal activity of commonly used chemical disinfectants against S. capitis was assessed.

FINDINGS

Of 173 surfaces sampled, 40 (21.1%) harboured S. capitis with 30 isolates (75%) being NRCS-A. Whereas S. capitis was recovered from surfaces across the NICU, the NRCS-A clone was rarely recovered from outside the immediate neonatal bedspace. Incubators and other bedside equipment were contaminated with NRCS-A regardless of clinical case detection. In the absence of cleaning, S. capitis was able to survive for three days with minimal losses in viability (<0.5 log10 reduction). Sodium troclosene and a QAC-based detergent/disinfectant reduced S. capitis to below detectable levels.

CONCLUSION

S. capitis NRCS-A can be readily recovered from the NICU environment, even in units with no recent reported clinical cases of S. capitis infection, highlighting a need for appropriate national guidance on cleaning within the neonatal care environment.

A qualitative exploration of stakeholder perspectives on the implementation of a whole school approach to mental health and emotional well-being in Wales

Early intervention to support mental health and well-being of school-aged children may be of significant benefit in preventing escalation of mental health problems in later life. While there are limitations to current understanding of the best ways for schools to support mental well-being, a whole school approach (WSA), involving all those who are part of the school system in creating and sustaining a supportive environment where health is prioritized, may be effective. This research explored stakeholder views of this approach, as part of a contract commissioned by the Welsh Government to conduct an evaluability assessment of a WSA. Semistructured focus groups and interviews were completed with stakeholders from the health and education sectors, as well as parents, to explore how a WSA may operate in a Welsh context and barriers and facilitators to potential implementation and outcomes. Findings suggest that existing pressures on schools may impact implementation of a WSA, with school staff already time poor and many staff experiencing their own mental well-being challenges. Implementation may be supported by clear guidance at local and national levels, funding for staff time and training and stakeholder involvement at all stages. Long-term monitoring and evaluation are also needed to understand system changes.

A central chaperone-like role for 14-3-3 proteins in human cells

14-3-3 proteins are highly conserved regulatory proteins that interact with hundreds of structurally diverse clients and act as central hubs of signaling networks. However, how 14-3-3 paralogs differ in specificity and how they regulate client protein function are not known for most clients. Here, we map the interactomes of all human 14-3-3 paralogs and systematically characterize the effect of disrupting these interactions on client localization. The loss of 14-3-3 binding leads to the coalescence of a large fraction of clients into discrete foci in a client-specific manner, suggesting a central chaperone-like function for 14-3-3 proteins. Congruently, the engraftment of 14-3-3 binding motifs to nonclients can suppress their aggregation or phase separation. Finally, we show that 14-3-3s negatively regulate the localization of the RNA-binding protein SAMD4A to cytoplasmic granules and inhibit its activity as a translational repressor. Our work suggests that 14-3-3s have a more prominent role as chaperone-like molecules than previously thought.

Measurement of SARS-CoV-2 in air and on surfaces in Scottish hospitals

BACKGROUND

There are still uncertainties in our knowledge of the amount of SARS-CoV-2 virus present in the environment - where it can be found, and potential exposure determinants - limiting our ability to effectively model and compare interventions for risk management.

AIM

This study measured SARS-CoV-2 in three hospitals in Scotland on surfaces and in air, alongside ventilation and patient care activities.

METHODS

Air sampling at 200 L/min for 20 min and surface sampling were performed in two wards designated to treat COVID-19-positive patients and two non-COVID-19 wards across three hospitals in November and December 2020.

FINDINGS

Detectable samples of SARS-CoV-2 were found in COVID-19 treatment wards but not in non-COVID-19 wards. Most samples were below assay detection limits, but maximum concentrations reached 1.7×10³ genomic copies/m³ in air and 1.9×10⁴ copies per surface swab (3.2×10² copies/cm² for surface loading). The estimated geometric mean air concentration (geometric standard deviation) across all hospitals was 0.41 (71) genomic copies/m³ and the corresponding values for surface contamination were 2.9 (29) copies/swab. SARS-CoV-2 RNA was found in non-patient areas (patient/visitor waiting rooms and personal protective equipment changing areas) associated with COVID-19 treatment wards.

CONCLUSION

Non-patient areas of the hospital may pose risks for infection transmission and further attention should be paid to these areas. Standardization of sampling methods will improve understanding of levels of environmental contamination. The pandemic has demonstrated a need to review and act upon the challenges of older hospital buildings meeting current ventilation guidance.

First experience of implementing Candida auris real-time PCR for surveillance in the UK: detection of multiple introductions with two international clades and improved patient outcomes

BACKGROUND

Candida auris has been associated with rapid transmission and high mortality. A novel PCR-based surveillance programme was initiated at a London teaching hospital from January 2018. The results of this implementation until March 2019 are presented along with the clinical, transmission and phylogenetic characteristics encountered in that setting.

METHODS

A real-time PCR assay for C. auris was developed, validated, and implemented for direct use on skin swabs and urine. Environmental swabs were also tested by PCR as an emergency outbreak-control measure. Clinical risk factors and outcomes of patients were determined. Environmental dispersal was assessed using 24 h settle plate cultures around nine colonized patients followed by air sampling around one colonized patient during high- and low-turbulence activities. Sequencing was performed using Illumina HiSeq and maximum likelihood phylogenies were constructed using rapid bootstrap analysis.

RESULTS

Twenty-one C. auris colonized patients were identified. Median turnaround time of colonization detection reduced from 141 h (5.8 days) to approximately 24 h enabling rapid infection-control precautions. Settle plates detected 70-600 cfu/m² around colonized patients over 24 h and air sampling suggested dispersal during turbulent activities. C. auris DNA was detected from 35.7% environmental swabs. Despite being in a high-risk setting, no patients developed invasive infection. Sequencing analysis of isolates from this centre identified two introductions of the South Asian (Clade I) and one of the South African (Clade III) strain.

CONCLUSION

The PCR offers a rapid, scalable method of screening and supports clinical risk reduction in settings likely to encounter multiple introductions.

SWATH-MS identification of CXCL7, LBP, TGFβ1 and PDGFRβ as novel biomarkers in human systemic mastocytosis

Mastocytosis is a rare myeloproliferative disease, characterised by accumulation of neoplastic mast cells in one or several organs. It presents as cutaneous or systemic. Patients with advanced systemic mastocytosis have a median survival of 3.5 years. The aetiology of mastocytosis is poorly understood, patients present with a broad spectrum of varying clinical symptoms that lack specificity to point clearly to a definitive diagnosis. Discovery of novel blood borne biomarkers would provide a tractable method for rapid identification of mastocytosis and its sub-types. Moving towards this goal, we carried out a clinical biomarker study on blood from twenty individuals (systemic mastocytosis: n = 12, controls: n = 8), which were subjected to global proteome investigation using the novel technology SWATH-MS. This identified several putative biomarkers for systemic mastocytosis. Orthogonal validation of these putative biomarkers was achieved using ELISAs. Utilising this workflow, we identified and validated CXCL7, LBP, TGFβ1 and PDGF receptor-β as novel biomarkers for systemic mastocytosis. We demonstrate that CXCL7 correlates with neutrophil count offering a new insight into the increased prevalence of anaphylaxis in mastocytosis patients. Additionally, demonstrating the utility of SWATH-MS for the discovery of novel biomarkers in the systemic mastocytosis diagnostic sphere.

A splash-reducing clinical handwash basin reduces droplet-mediated dispersal from a sink contaminated with Gram-negative bacteria in a laboratory model system

Infection prevention strategies need to be identified and evaluated to reduce the risk associated with contaminated hospital sinks. This study used settle plates to compare the dispersal of Gram-negative bacteria from a conventional, rear-draining clinical handwash basin (CHWB) and a 'splash-reducing' CHWB with and/or without impaired drainage. Two scenarios were assessed: dispersal from a contaminated basin and dispersal from a contaminated drain. The associated tap was operated for 1 min and, for all contamination scenarios, the 'splash-reducing' CHWB had significantly lower odds of spreading contamination than the conventional CHWB.

Adapting evidence-informed population health interventions for new contexts: a scoping review of current practice

BACKGROUND

Implementing evidence-informed population health interventions in new contexts often requires adaptations. While the need to adapt interventions to better fit new contexts is recognised, uncertainties remain regarding why and when to adapt (or not), and how to assess the benefits (or not) of adaptation. The ADAPT Study aims to develop comprehensive guidance on adaptation. This scoping review informs guidance development by mapping and exploring how adaptation has been undertaken in practice, in public health and health services research.

METHODS

We searched seven databases from January 2000 and October 2018 to identify eligible studies for this scoping review and a related systematic review of adaptation guidance. We mapped the studies of adaptation by coding data from all eligible studies describing the methods, contexts, and interventions considered for adaptation. From this map, we selected a sample of studies for in-depth examination. Two reviewers extracted data independently into seven categories: description, key concepts, types, rationale, processes, evaluation methods, evaluation justification, and accounts of failures and successes.

RESULTS

We retrieved 6694 unique records. From 429 records screened at full text, we identified 298 eligible studies for mapping and selected 28 studies for in-depth examination. The majority of studies in our map focused on micro- (i.e., individual-) level interventions (84%), related to transferring an intervention to a new population group within the same country (62%) and did not report using guidance (73%). Studies covered a range of topic areas, including health behaviour (24%), mental health (19%), sexual health (16%), and parenting and family-centred interventions (15%). Our in-depth analysis showed that adaptation is seen to save costs and time relative to developing a new intervention, and to enhance contextual relevance and cultural compatibility. It commonly follows a structured process and involves stakeholders to help with decisions on what to adapt, when, and how.

CONCLUSIONS

Adaptation has been undertaken on a range of health topics and largely in line with existing guidance. Significant gaps relate to adaptation of macro- (e.g., national-) level interventions, consideration of programme theories, mechanisms and contexts (i.e., a functional view of interventions), nuances around stakeholder involvement, and evaluation of the adapted interventions. Registration Open Science Framework, 2019, osf.io/udzma.

Detection of SARS-CoV-2 within the healthcare environment: a multi-centre study conducted during the first wave of the COVID-19 outbreak in England

BACKGROUND

Understanding how severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is spread within the hospital setting is essential in order to protect staff, implement effective infection control measures, and prevent nosocomial transmission.

METHODS

The presence of SARS-CoV-2 in the air and on environmental surfaces around hospitalized patients, with and without respiratory symptoms, was investigated. Environmental sampling was undertaken within eight hospitals in England during the first wave of the coronavirus disease 2019 outbreak. Samples were analysed using reverse transcription polymerase chain reaction (PCR) and virus isolation assays.

FINDINGS

SARS-CoV-2 RNA was detected on 30 (8.9%) of 336 environmental surfaces. Cycle threshold values ranged from 28.8 to 39.1, equating to 2.2 x 105 to 59 genomic copies/swab. Concomitant bacterial counts were low, suggesting that the cleaning performed by nursing and domestic staff across all eight hospitals was effective. SARS-CoV-2 RNA was detected in four of 55 air samples taken <1 m from four different patients. In all cases, the concentration of viral RNA was low and ranged from <10 to 460 genomic copies/m3 air. Infectious virus was not recovered from any of the PCR-positive samples analysed.

CONCLUSIONS

Effective cleaning can reduce the risk of fomite (contact) transmission, but some surface types may facilitate the survival, persistence and/or dispersal of SARS-CoV-2. The presence of low or undetectable concentrations of viral RNA in the air supports current guidance on the use of specific personal protective equipment for aerosol-generating and non-aerosol-generating procedures.

Change over time in adolescent smoking, cannabis use and their association: findings from the School Health Research Network in Wales

Background

While tobacco smoking has declined among UK youth in recent decades, cannabis use has begun to show some growth. Given their interrelationship, growth in cannabis use may act as a barrier to continued reduction in youth smoking. This paper assesses recent tobacco and cannabis use trends in Wales, and their association, to explore whether change in cannabis use might have impacted youth tobacco smoking prevalence.

Methods

Repeat cross-sectional data on tobacco and cannabis use were obtained from biennial Welsh Student Health and Wellbeing surveys between 2013 and 2019. Data were pooled and analysed using logistic regression with adjustment for school-level clustering.

Results

No change in regular youth tobacco smoking was observed between 2013 and 2019. In contrast, current cannabis use increased during this time, and cannabis users had significantly greater odds of regular tobacco smoking. After adjusting for change in cannabis use, a significant decline in youth tobacco smoking was observed (OR 0.95; 95% confidence intervals: 0.92, 0.97).

Conclusion

Recent growth in cannabis use among young people in Wales may have offset prospective declines in regular tobacco smoking. Further reductions in youth smoking may require more integrated policy approaches to address the co-use of tobacco and cannabis among adolescents.

Investigating alternative materials to EPDM for automatic taps in the context of Pseudomonas aeruginosa and biofilm control

BACKGROUND

Automatic taps use solenoid valves (SVs) which incorporate a rubber (typically EPDM) diaphragm to control water flow. Contaminated SVs can be reservoirs of opportunistic pathogens such as Pseudomonas aeruginosa; an important cause of healthcare-associated infection.

AIMS

To investigate the attachment and biofilm formation of P. aeruginosa on EPDM and relevant alternative rubbers to assess the impact on water hygiene in a laboratory model.

METHODS

Biofilm formation on EPDM, silicone and nitrile rubber coupons was investigated using a CDC biofilm reactor. SVs incorporating EPDM or nitrile rubber diaphragms were installed on to an experimental water distribution system (EWDS) and inoculated with P. aeruginosa. P. aeruginosa water levels were monitored for 12-weeks. SVs incorporating diaphragms (EPDM, silicone or silver ion-impregnated silicone rubber), pre-colonized with P. aeruginosa, were installed and the effect of flushing as a control measure was investigated. The concentration of P. aeruginosa in the water was assessed by culture and biofilm assessed by culture and microscopy.

FINDINGS

Bacterial attachment was significantly higher on nitrile (6.2 × 10⁵ cfu/coupon) and silicone (5.4 × 10⁵ cfu/coupon) rubber than on EPDM (2.9 ×10⁵ cfu/coupon) (P<0.05, N = 17). Results obtained in vitro did not translate to the EWDS where, after 12-weeks in situ, there was no significant difference in P. aeruginosa water levels or biofilm levels. Flushing caused a superficial reduction in bacterial counts after <5 min of stagnation.

CONCLUSION

This study did not provide evidence to support replacement of EPDM with (currently available) alternative rubbers and indicated the first sample of water dispensed from a tap should be avoided for use in healthcare settings.

Training the next generation in transdisciplinarity

Background

Transdisciplinarity is ideally suited to investigating the determinants of health, as it requires the understanding of multiple, interlinking factors such as poverty, culture, education, environment, and public policy. In this study, we set out to understand how others have taught transdisciplinary research methods to identify common teaching methods and best practices.

Methods

We conducted two separate literature reviews using OVID Medline. The first identified articles that conducted transdisciplinary research and the second focused on teaching transdisciplinary research. Studies from both searches were included if they described the methods used to teach transdisciplinary research. Data were extracted on teaching strategies, student assessment, and the cited benefits of both.

Results

Our search of transdisciplinary research papers provided 528 papers whilst our search on teaching transdisciplinary research methods identified 100. After screening, we included 23 papers. Forms of teaching transdisciplinary research were diverse, and included mentoring and multi-mentoring to learn from the experiences of others, small group work to develop interpersonal transdisciplinary skills, immersion in real-life experiences to develop research skills and peer discussion groups to facilitate peer-peer learning. Assessment methods included critical evaluations of past projects and group coursework.

Conclusions

Our review highlighted that a combination of interactive, problem-based discussion and hands-on learning experiences (assessed and non-assessed) were used for transdisciplinary learning and skills acquisition, which needs to be combined with an assortment of exposures to different disciplines in the forms of lectures, readings and learning material.

Key messages

Training the next generation in transdisciplinarity involves a diverse range of methods including immersion in real-life experiences. Transdisciplinary teaching involves an assortment of exposures to different disciplines in the forms of lectures, readings and learning material.

Influence of granular activated carbon media properties on natural organic matter and disinfection by-product precursor removal from drinking water

Operational and financial constraints challenge effective removal of natural organic matter (NOM), and specifically disinfection by-product (DBP) precursors, at remote and/or small sites. Granular activated carbon (GAC) is a widely used treatment option for such locations, due to its relatively low maintenance and process operational simplicity. However, its efficacy is highly dependent on the media capacity for the organic matter, which in turn depends on the media characteristics. The influence of GAC media properties on NOM/DBP precursor removal has been studied using a range of established and emerging media using both batch adsorption tests and rapid small-scale column tests. DBP formation propensity (DBPFP) was measured with reference to trihalomethanes (THMs) and haloacetic acids (HAAs). All GAC media showed no selectivity for specific removal of precursors of regulated DBPs; DBP formation was a simple function of residual dissolved organic carbon (DOC) levels. UV₂₅₄ was found to be a good surrogate measurement of DBPFP for an untreated water source having a high DOC. Due to the much-reduced concentration of DBP precursors, the correlation was significantly poorer for the coagulation/flocculation-pretreateed water source. Breakthrough curves generated from the microcolumn trials revealed DOC removal and consequent DBP reduction to correlate reasonably well with the prevalence pores in the 5-10 nm range. A 3-6 fold increase in capacity was recorded for a 0.005-0.045 cm³/g change in 5-10 nm-sized pore volume density. No corresponding correlation was evident with other media pore size ranges.

The combined influence of hydrophobicity, charge and molecular weight on natural organic matter removal by ion exchange and coagulation

Three different source waters were investigated using virgin and pre-used anion exchange resins, coagulation, and ion exchange combined with coagulation (IEX&Coagulation). The hydrophobicity, size distribution and charge of natural organic matter (NOM) were used to evaluate its removal. Dissolved organic carbon (DOC) removal by pre-used IEX resin was 67-79%. A consistent ratio of different hydrophobicity fractions was found in the removed DOC, while the proportion and quantity of the molecular weight fraction around 1 kDa was important in understanding the treatability of water. For pre-used resin, organic compounds were hypothesised to be restricted to easily accessible exchange sites. Comparatively, virgin resin achieved higher DOC removals (86-89%) as resin fouling was absent. Charge density and the proportion of the hydrophobic fraction were found to be important indicators for the specific disinfection byproduct formation potential (DBP-FP). Treatment of raw water with pre-used resin decreased the specific DBP-FP by between 2 and 43%, while the use of virgin resin resulted in a reduction of between 31 and 63%. The highest water quality was achieved when the combination of IEX and coagulation was used, reducing DOC and the specific DBP-FP well below that seen for either process alone.

Adapting evidence-informed complex population health interventions for new contexts: a systematic review of guidance

BACKGROUND

Adapting interventions that have worked elsewhere can save resources associated with developing new interventions for each specific context. While a developing body of evidence shows benefits of adapted interventions compared with interventions transported without adaptation, there are also examples of interventions which have been extensively adapted, yet have not worked in the new context. Decisions on when, to what extent, and how to adapt interventions therefore are not straightforward, particularly when conceptualising intervention effects as contingent upon contextual interactions in complex systems. No guidance currently addresses these questions comprehensively. To inform development of an overarching guidance on adaptation of complex population health interventions, this systematic review synthesises the content of the existing guidance papers.

METHODS

We searched for papers published between January 2000 and October 2018 in 7 bibliographic databases. We used citation tracking and contacted authors and experts to locate further papers. We double screened all the identified records. We extracted data into the following categories: descriptive information, key concepts and definitions, rationale for adaptation, aspects of adaptation, process of adaptation, evaluating and reporting adapted interventions. Data extraction was conducted independently by two reviewers, and retrieved data were synthesised thematically within pre-specified and emergent categories.

RESULTS

We retrieved 6694 unique records. Thirty-eight papers were included in the review representing 35 sources of guidance. Most papers were developed in the USA in the context of implementing evidence-informed interventions among different population groups within the country, such as minority populations. We found much agreement on how the papers defined key concepts, aims, and procedures of adaptation, including involvement of key stakeholders, but also identified gaps in scope, conceptualisation, and operationalisation in several categories.

CONCLUSIONS

Our review found limitations that should be addressed in future guidance on adaptation. Specifically, future guidance needs to be reflective of adaptations in the context of transferring interventions across countries, including macro- (e.g. national-) level interventions, better theorise the role of intervention mechanisms and contextual interactions in the replicability of effects and accordingly conceptualise key concepts, such as fidelity to intervention functions, and finally, suggest evidence-informed strategies for adaptation re-evaluation and reporting.

TRIAL REGISTRATION

PROSPERO 2018, CRD42018112714.

Associations between school-based peer networks and smoking according to socioeconomic status and tobacco control context: protocol for a mixed method systematic review

BACKGROUND

Smoking remains a major public health concern. School-based social networks influence uptake of smoking among peers. During the past two decades, the UK macro-systemic context within which schools are nested and interact with has changed, with anti-smoking norms having become set at a more macro-systemic level. Whilst the overall prevalence of smoking in the UK has decreased, inequality has prevailed. It is plausible that the influence of school-based social networks on smoking uptake may vary according to socioeconomic status. Therefore, this study aims to understand how social influence on smoking among adolescents has changed in line with variance within and between contexts according to time and geography.

METHODS

The following databases will be searched: Medline, PsycINFO, Embase, Applied Social Sciences Index and Abstracts (ASSIA), British Education Index, Sociological abstracts, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Education Resources Information Center (ERIC) and Scopus. Additional searches will include reference checking of key papers, citation tracking, word of mouth and grey literature searches. The search strategies will incorporate terms relating to smoking, adolescents, schools, peers, network analysis and qualitative research. Titles and abstracts and full texts will be independently screened and assessed for quality by at least two researchers. Included studies will be assessed for quality, and data will be extracted for synthesis, including participant characteristics, setting and tobacco control context, study design and methods, analysis and results and conclusions. Quantitative findings will be narratively synthesised, whilst a lines of argument synthesis combined with refutational analysis will be employed to synthesise qualitative data. Both sets of findings will be charted on a timeline to add context to network findings and obtain an enhanced understanding of changes over time.

DISCUSSION

This protocol is for a mixed methods synthesis of both social network findings, to investigate social structures and qualitative studies, to elicit contextual information. The review will synthesise changes in the context of social influence on adolescent smoking over time and geographically. As context is increasingly recognised as a key source of complexity, this enhanced understanding will help to inform future interventions targeting smoking through social influence. This will help to enhance their relevance to context, subsequent effectiveness and targeting of inequalities.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019137358.

A qualitative study of e-cigarette emergence and the potential for renormalisation of smoking in UK youth

Background

Growth of e-cigarette use among smokers has raised concerns over uptake by non-smokers, particularly young people. Legislative changes aimed in part at reducing youth exposure to e-cigarettes include the EU Tobacco Products Directive (TPD). A core justification for such measures is the belief that e-cigarettes can lead to tobacco smoking through mechanisms of renormalisation including: mimicking and normalizing the act of smoking; increasing product acceptability via marketing; nicotine exposure. These mechanisms are here explored in relation to findings from qualitative research.

Methods

This paper reports results from twenty-one group interviews with 14–15 year olds in Wales, England and Scotland, conducted as part of an ongoing evaluation of the impact of the TPD on youth smoking and e-cigarette use. Interviews were conducted around the end of the transitional period for TPD implementation, and explored perceptions of e-cigarettes and tobacco, as well as similarities and differences between them.

Results

Young people differentiated between tobacco and e-cigarettes, rejecting the term e-cigarette in favour of alternatives such as ‘vapes’. Experimental or occasional use was common and generally approved of where occurring within social activity with peers. However, regular use outside of this context was widely disapproved of, unless for the purpose of stopping smoking. Increased prevalence of e-cigarettes did not challenge strongly negative views of smoking or reduce perceived harms caused by it, with disapproval of smoking remaining high. Nicotine use was variable, with flavour a stronger driver for choice of e-liquid, and interest more generally.

Conclusion

The extent to which participants differentiated between vaping and smoking, including styles and reasons for use in adults and young people; absence of marketing awareness; and continued strong disapproval of smoking provides limited support for some of the potential mechanisms through which e-cigarettes may renormalise smoking. However caution over nicotine exposure is still necessary.

Use of e-cigarettes by young people in Great Britain before and after Tobacco Products Directive

Background

Young people’s experimentation with e-cigarettes has increased in recent years, although regular use remains rare. In May 2016, the EU Tobacco Products Directive (TPD) introduced regulations aimed in part at preventing use by young people. It imposed warnings on e-cigarette packets, banned many forms of advertising, and restricted nicotine strength. This paper examines change in young people’s e-cigarette use after TPD, as well as complementary and alternative causal explanations for change, from young people’s perspectives.

Methods

Quantitative data sources were 2013, 2015 and 2017 School Health Research Network/Health Behaviour in School-aged Children surveys in Wales and 2014 and 2016 Smoking Drinking and Drug Use surveys in England. Data were analysed using segmented binary logistic regression in Wales, with simpler before and after analyses in England. Results were considered alongside qualitative interview data from young people aged 14-15 years in England, Wales and Scotland, collected in 2017 and 2018.

Results

Ever-use of e-cigarettes almost doubled from 2013-15, though subsequent increases were smaller. In Wales, where pre-legislation time series data were available, under a range of assumptions, prior growth in e-cigarette ever-use did not continue post-TPD. Change in trend post-TPD did not reach significance (OR = 0.96; 95%CI=0.91 to 1.01), but became significant after adjusting for change in smoking rates across the time-series (OR = 0.93; 95%CI=0.88 to 0.98). Regular use did not increase significantly from 2015 to 2017 in Wales, although ever and regular use in England both increased from 2014 to 2016. Young people described limited interactions with core components of TPD, while commonly describing e-cigarette use as a fad which was beginning to run its course.

Conclusions

Growth in youth experimentation with e-cigarettes may be slowing. Qualitative data from young people provide a range of explanations which appear largely unrelated to TPD itself.

Key messages

Survey data provide preliminary evidence that use of e-cigarettes may be plateauing among young people in the UK after a rapid initial increase in experimentation. Explanations position e-cigarettes as a passing fad which is beginning to lose its appeal in UK youth. Longer term monitoring of trends and perceptions remain vital.

Massive clonal expansion of medulloblastoma-specific T cells during adoptive cellular therapy

In both human and murine systems, we have developed an adoptive cellular therapy platform against medulloblastoma and glioblastoma that uses dendritic cells pulsed with a tumor RNA transcriptome to expand polyclonal tumor-reactive T cells against a plurality of antigens within heterogeneous brain tumors. We demonstrate that peripheral TCR Vβ repertoire analysis after adoptive cellular therapy reveals that effective response to adoptive cellular therapy is concordant with massive in vivo expansion and persistence of tumor-specific T cell clones within the peripheral blood. In preclinical models of medulloblastoma and glioblastoma, and in a patient with relapsed medulloblastoma receiving adoptive cellular therapy, an early and massive expansion of tumor-reactive lymphocytes, coupled with prolonged persistence in the peripheral blood, is observed during effective therapeutic response to immunotherapy treatment.

Put a Bow on It: Knotted Antibiotics Take Center Stage

Ribosomally-synthesized and post-translationally modified peptides (RiPPs) are a large class of natural products produced across all domains of life. The lasso peptides, a subclass of RiPPs with a lasso-like structure, are structurally and functionally unique compared to other known peptide antibiotics in that the linear peptide is literally "tied in a knot" during its post-translational maturation. This underexplored class of peptides brings chemical diversity and unique modes of action to the antibiotic space. To date, eight different lasso peptides have been shown to target three known molecular machines: RNA polymerase, the lipid II precursor in peptidoglycan biosynthesis, and the ClpC₁ subunit of the Clp protease involved in protein homeostasis. Here, we discuss the current knowledge on lasso peptide biosynthesis as well as their antibiotic activity, molecular targets, and mechanisms of action.

Identical and Nonidentical Twins: Risk and Factors Involved in Development of Islet Autoimmunity and Type 1 Diabetes

OBJECTIVE

There are variable reports of risk of concordance for progression to islet autoantibodies and type 1 diabetes in identical twins after one twin is diagnosed. We examined development of positive autoantibodies and type 1 diabetes and the effects of genetic factors and common environment on autoantibody positivity in identical twins, nonidentical twins, and full siblings.

RESEARCH DESIGN AND METHODS

Subjects from the TrialNet Pathway to Prevention Study (N = 48,026) were screened from 2004 to 2015 for islet autoantibodies (GAD antibody [GADA], insulinoma-associated antigen 2 [IA-2A], and autoantibodies against insulin [IAA]). Of these subjects, 17,226 (157 identical twins, 283 nonidentical twins, and 16,786 full siblings) were followed for autoantibody positivity or type 1 diabetes for a median of 2.1 years.

RESULTS

At screening, identical twins were more likely to have positive GADA, IA-2A, and IAA than nonidentical twins or full siblings (all P < 0.0001). Younger age, male sex, and genetic factors were significant factors for expression of IA-2A, IAA, one or more positive autoantibodies, and two or more positive autoantibodies (all P ≤ 0.03). Initially autoantibody-positive identical twins had a 69% risk of diabetes by 3 years compared with 1.5% for initially autoantibody-negative identical twins. In nonidentical twins, type 1 diabetes risk by 3 years was 72% for initially multiple autoantibody-positive, 13% for single autoantibody-positive, and 0% for initially autoantibody-negative nonidentical twins. Full siblings had a 3-year type 1 diabetes risk of 47% for multiple autoantibody-positive, 12% for single autoantibody-positive, and 0.5% for initially autoantibody-negative subjects.

CONCLUSIONS

Risk of type 1 diabetes at 3 years is high for initially multiple and single autoantibody-positive identical twins and multiple autoantibody-positive nonidentical twins. Genetic predisposition, age, and male sex are significant risk factors for development of positive autoantibodies in twins.

Carbapenem-resistant Enterobacteriaceae dispersal from sinks is linked to drain position and drainage rates in a laboratory model system

BACKGROUND

Hospital sinks, waste traps and drains can harbour carbapenem-resistant Enterobacteriaceae (CRE).

AIM

To investigate the dispersal of CRE from sinks in which water delivered from the tap flows directly into the drain and from clinical handwash basins with the drain at the rear. The effect of fast and slow drainage rates was also assessed.

METHODS

Waste traps, known to be colonized with CRE, were taken from a hospital and installed within a model laboratory system. New waste traps were also installed and artificially inoculated with CRE. The potential for bacteria to be dispersed from sinks was assessed using cyclone air samplers and/or settle plates.

FINDINGS

When the waste traps were artificially contaminated and CRE colonization was confined to the waste trap water, significantly fewer bacteria were dispersed from sinks that drained quickly (P = 0.004) and/or from rear-draining sinks (P = 0.002). When the waste traps were naturally contaminated and CRE colonized the trap, pipework and drain, there was significant interaction between sink drainage and position of the drain (P < 0.001). When drainage was slow, dispersal from rear-draining sinks was almost 30-fold less than from sinks with the drain underneath the tap (P < 0.001). When drainage was fast, rear-draining sinks again released comparatively fewer CRE, although, in this case, the difference was not statistically significant (P = 0.7). Contaminated splashes travelled up to 1 m from the sink.

CONCLUSION

Slow drainage rates and sink designs with the drain directly underneath the tap increase the risk of CRE present in waste traps and drains contaminating the ward environment.

Deconstructing knowledge brokering for commissioned rapid reviews: an observational study

Background

Knowledge brokers are increasingly used by policy agencies, yet little is known about how they engage with policy-makers and facilitate discussions with them about their research needs. This study examines knowledge brokers’ behaviour in one-off interactions with policy-makers commissioning rapid reviews. It describes how knowledge brokers engage with policy-makers, build trust and gain agreement about the review’s parameters.

Methods

We observed and transcribed 15 structured knowledge brokering sessions and used line-by-line analysis to derive, test and refine a coding schedule. The final coding schedule was applied to all transcripts. We assigned 35 codes to three tasks identified in the data, namely eliciting information, exploring the policy context and negotiating the content of reviews.

Results

The knowledge brokers we observed were skilled facilitators who built trust by their open stance, neutrality, and knowledge of research and policy contexts. Trust engendered an interplay of expertise in which review questions and scope were clarified and contextual factors evaluated. Negotiation about the content of the review focused on understanding how it would contribute to the policy process, comparing options and assessing feasibility. Key functions of knowledge brokers included eliciting and clarifying information, linking the review questions to the context and purpose, moving fluidly between policy and research perspectives, and weighing up review options against policy objectives. Four knowledge brokering roles were identified, namely diagnostic, facilitative, deliberative and interpretative.

Conclusions

This study identified ways in which knowledge brokers established rapport with policy-makers who commissioned reviews, enabled disclosure of essential information and explored contextual factors that affected the review’s purpose and intended use. Knowledge brokers were competent in the discourse and conventions of both policy and research and were skilled in negotiating complex policy and political environments, assisting policy-makers to evaluate options and craft a review proposal that was targeted, responsive and feasible. Mutuality, respect and an interplay of expertise were integral to the knowledge brokering process. Future research might usefully examine whether other rapid review programmes using knowledge brokers have similar results as well as the transferability of the four knowledge brokering roles to other contexts and settings.

Electronic supplementary material

The online version of this article (10.1186/s12961-018-0389-7) contains supplementary material, which is available to authorized users.

Understanding the potential for selective natural organic matter removal by ion exchange

Dissolved organic carbon (DOC) removal from a river water source was investigated using ion exchange (IEX), coagulation and membrane filtration. This research linked the variable charge characteristics of the organic compounds present in the source water with removal by IEX and coagulation. The raw water charge density fluctuated considerably (between 5.4 and 10.7 meq mg_DOC^-1) and controlled removal of the charge loading. Importantly, charge density was not correlated with the organic carbon concentration. The combined IEX and coagulation process reduced the specific DBP-FP (sDBP-FP) of the final water, with values as low as 18 μg mg_DOC^-1 for both haloacetic acids and trihalomethanes. IEX removed a particular fraction of NOM that 1) enhanced coagulation efficiency, providing increased removal of overall DOC; and 2) enabled coagulation to subsequently remove higher levels of specific components of NOM that have a high DBP-FP. The component of NOM removed by IEX that had a positive impact on coagulation was identified to be charged low molecular weight organic compounds of all hydrophobicity levels, resulting in a reduced specific DBP-FP compared to coagulation alone.

The presence and prevalence of Legionella spp in collected rainwater and its aerosolisation during common gardening activities

AIMS

To determine the presence and prevalence of Legionella spp in domestic rainwater storage butts and to quantify its aerosolisation when collected rainwater is used for common gardening activities.

METHODS

Volunteers were asked to take a water sample from their garden rainwater storage butt. The presence of Legionella was determined using quantitative polymerase chain reaction (qPCR). Two new rainwater storage butts were installed on-site at PHE Porton and positioned in sunlight or in the shade. Ambient conditions and those within the two 'experimental' water butts were continually monitored. A cyclone air sampler was used to detect the presence of Legionella in the air when collected rainwater was poured from a watering can or delivered via a hosepipe attached to a submersible water butt pump.

RESULTS

A total of 63 volunteers provided water samples from 113 different rainwater storage butts. Legionella spp was detected in 107 of these samples at a mean concentration of 4.7 × 10⁴ genomic units l^-1. Two of these samples also contained L. pneumophila. The water butt positioned in the shade stored water at a significantly lower temperature than that exposed to sunlight. While the concentration of Legionella was significantly higher in this cooler water, meteorological conditions rather than conditions within the water butt had the greatest effect upon Legionella concentration. No Legionella was detected in the air when rainwater was poured from a watering can. However, using a hose pipe on a 'fine spray' setting increased both the number of organisms detected in the air and their dissemination.

CONCLUSION

In this study, Legionella spp were common contaminants of collected rainwater. However, the use of rainwater for common gardening activities should not be discouraged. Aerosolisation of Legionella when using a watering can is minimal and any increased risk associated with hose pipe use can be mitigated by using a coarse spray setting.

Pseudomonas aeruginosa adapts to octenidine in the laboratory and a simulated clinical setting, leading to increased tolerance to chlorhexidine and other biocides

BACKGROUND

Octenidine is frequently used for infection prevention in neonatal and burn intensive care units, where Pseudomonas aeruginosa has caused nosocomial outbreaks.

AIM

To investigate the efficacy and impact of using octenidine against P. aeruginosa.

METHODS

Seven clinical isolates of P. aeruginosa were exposed to increasing concentrations of octenidine over several days. Fitness, minimum bactericidal concentrations after 1 min, 5 min and 24 h, and minimum inhibitory concentrations (MICs) of a variety of antimicrobials were measured for the parental and octenidine-adapted P. aeruginosa strains. Octenidine and chlorhexidine MICs of a population of P. aeruginosa isolated from a hospital drain trap, exposed to a diluted octenidine formulation four times daily for three months, were also tested.

FINDINGS

Some planktonic cultures of P. aeruginosa survived >50% of the working concentration of an in-use octenidine formulation at the recommended exposure time. Seven strains of P. aeruginosa stably adapted following continuous exposure to increasing concentrations of octenidine. Adaptation increased tolerance to octenidine formulations and chlorhexidine up to 32-fold. In one strain, it also led to increased MICs of antipseudomonal drugs. Subsequent to continuous octenidine exposure of a multi-species community in a simulated clinical setting, up to eight-fold increased tolerance to octenidine and chlorhexidine of P. aeruginosa was also found, which was lost upon removal of octenidine.

CONCLUSION

Incorrect use of octenidine formulations may lead to inadequate decontamination, and even increased tolerance of P. aeruginosa to octenidine, with resulting cross-resistance to other biocides.

Contamination of hospital tap water: the survival and persistence of Pseudomonas aeruginosa on conventional and 'antimicrobial' outlet fittings

BACKGROUND

Pseudomonas aeruginosa infections have been linked to contaminated hospital taps, highlighting the potential for tap outlet fittings (OF) to harbour biofilm. P. aeruginosa may be transferred to OFs via contaminated cleaning cloths. Suggested interventions include flushing regimens and alternative OF designs.

AIM

To investigate the transfer of P. aeruginosa from a contaminated cleaning cloth to conventional and 'antimicrobial/antibiofilm' OFs and to determine whether this contamination persists and/or leads to contamination of tap water.

METHODS

Microfibre cloths contaminated with P. aeruginosa (10⁸ cfu/mL) were used to wipe four different types of OF [one of conventional design (OF-A) and three marketed as 'antimicrobial' and/or 'antibiofilm' (OF- B, -C and -D)]. OFs were inserted into an experimental water distribution system for up to 24 h. Survival was assessed by culture. Single and multiple water samples were collected and cultured for P. aeruginosa.

FINDINGS

The median number of P. aeruginosa transferred from cloth to OF was 5.7 × 10⁵ cfu (OF-A), 1.9 × 10⁶ cfu (OF-B), 1.4 × 10⁵ cfu (OF-C) and 2.9 × 10⁶ cfu (OF-D). Numbers declined on all OFs during the 24 h period with log reductions ranging from 3.5 (OF-C) to 5.2 (OF-B; P > 0.05). All water samples delivered immediately after OF contamination contained P. aeruginosa at ≥10 cfu per 100 mL. Contamination of water delivered from OF-A persisted despite continued flushing. Water delivered from OF-B did not contain P. aeruginosa beyond the first flush.

CONCLUSION

Contaminated cleaning cloths may transfer P. aeruginosa to OFs, leading to contamination of tap water. Although not removing the potential for contamination, 'antimicrobial/antibiofilm' OFs may prevent P. aeruginosa from continually contaminating water delivered from the outlet.

Microbiological problems and biofilms associated with Mycobacterium chimaera in heater-cooler units used for cardiopulmonary bypass

The role of heater-cooler units (HCUs) in the transmission of Mycobacterium chimaera during open heart surgery has been recognized since 2013. Subsequent investigations uncovered a remarkable global outbreak reflecting the wide distribution of implicated devices. HCUs are an essential component of cardiopulmonary bypass operations and their withdrawal would severely affect capacity for life-saving cardiac surgery. However, studies have demonstrated that many HCUs are contaminated with a wide range of micro-organisms, including M. chimaera and complex biofilms. Whole genome sequencing of M. chimaera isolates recovered from one manufacturer's HCUs, worldwide, has demonstrated a high level of genetic similarity, for which the most plausible hypothesis is a point source contamination of the devices. Dissemination of bioaerosols through breaches in the HCU water tanks is the most likely route of transmission and airborne bacteria have been shown to have reached the surgical field even with the use of ultraclean theatre ventilation. Controlling the microbiological quality of the water circulating in HCUs and reducing biofilm formation has been a major challenge for many hospitals. However, enhanced decontamination strategies have been recommended by manufacturers, and, although they are not always effective in eradicating M. chimaera from HCUs, UK hospitals have not reported any new cases of M. chimaera infection since implementing these mitigation strategies. Water safety groups in hospitals should be aware that water in medical devices such as HCUs may act as a vector in the transmission of potentially fatal water-borne infections.

THM and HAA formation from NOM in raw and treated surface waters

The disinfection by-product (DBP) formation potential (FP) of natural organic matter (NOM) in surface water sources has been studied with reference to the key water quality determinants (WQDs) of UV absorption (UV₂₅₄), colour, and dissolved organic carbon (DOC) concentration. The data set used encompassed raw and treated water sampled over a 30-month period from 30 water treatment works (WTWs) across Scotland, all employing conventional clarification. Both trihalomethane (THM) and haloacetic acid (HAA) FPs were considered. In addition to the standard bulk WQDs, the DOC content was fractionated and analysed for the hydrophobic (HPO) and hydrophilic (HPI) fractions. Results were quantified in terms of the yield (dDBPFP/dWQD) and the linear regression coefficient R² of the yield trend. The NOM in the raw waters was found to comprise 30-84% (average 66%) of the more reactive HPO material, with this proportion falling to 18-63% (average 50%) in the treated water. Results suggested UV₂₅₄ to be as good an indicator of DBPFP as DOC or HPO for the raw waters, with R² values ranging from 0.79 to 0.82 for THMs and from 0.71 to 0.73 for HAAs for these three determinants. For treated waters the corresponding values were significantly lower at 0.52-0.67 and 0.46-0.47 respectively, reflecting the lower HPO concentration and thus UV₂₅₄ absorption and commensurately reduced precision due to the limit of detection of the analytical instrument. It is concluded that fractionation offers little benefit in attempting to discern or predict chlorinated carbonaceous DBP yield for the waters across the geographical region studied. UV₂₅₄ offered an adequate estimate of DBPFP based on a mean yield of ∼2600 and ∼2800 μg per cm^-1 absorbance for THMFP for the raw and treated waters respectively and ∼3800 and2900 μg cm^-1 for HAAFP, albeit with reduced precision for the treated waters.

Orientation and stability of a bi-functional aromatic organic molecular adsorbate on silicon

In this work we combine scanning tunneling microscopy, near-edge X-ray absorption fine structure spectroscopy, X-ray photoemission spectroscopy and density functional theory to resolve a long-standing confusion regarding the adsorption behaviour of benzonitrile on Si(001) at room temperature.

Growth and hormone profiling in children with congenital melanocytic naevi

Background

Multiple congenital melanocytic naevi (CMN) is a rare mosaic RASopathy, caused by postzygotic activating mutations in NRAS. Growth and hormonal disturbances are described in germline RASopathies, but growth and hormone status have not previously been investigated in individuals with CMN.

Objectives

To explore premature thelarche, undescended testes, and a clinically abnormal fat distribution with CMN through prospective endocrinological assessment of a cohort of subjects with CMN, and a retrospective review of longitudinal growth of a larger group of patients with CMN from outpatient clinics (which included all subjects in the endocrinological assessment group).

Patients and methods

Longitudinal growth in a cohort of 202 patients with single or multiple CMN was compared with the U.K. National Child Measurement Programme 2010. Forty‐seven children had hormonal profiling including measurement of circulating luteinizing hormone, follicle‐stimulating hormone, thyroid stimulating hormone, adrenocorticotrophic hormone, growth hormone, prolactin, pro‐opiomelanocortin, estradiol, testosterone, cortisol, thyroxine, insulin‐like growth factor‐1 and leptin; 10 had oral glucose tolerance testing 25 had dual‐energy X‐ray absorptiometry scans for body composition.

Results

Body mass index increased markedly with age (coefficient 0·119, SE 0·016 standard deviation scores per year), at twice the rate of the U.K. population, due to increased adiposity. Three per cent of girls had premature thelarche variant and 6% of boys had persistent undescended testes. Both fat and muscle mass were reduced in areas underlying large naevi, resulting in limb asymmetry and abnormal truncal fat distribution. Anterior pituitary hormone profiling revealed subtle and variable abnormalities. Oral glucose tolerance tests revealed moderate–severe insulin insensitivity in five of 10, and impaired glucose tolerance in one.

Conclusions

Interpersonal variation may reflect the mosaic nature of this disease and patients should be considered individually. Postnatal weight gain is potentially related to the underlying genetic defect; however, environmental reasons cannot be excluded. Naevus‐related reduction of fat and muscle mass suggests local hormonal or metabolic effects on development or growth of adjacent tissues, or mosaic involvement of these tissues at the genetic level. Premature thelarche and undescended testes should be looked for, and investigated, as for any child.

What's already known about this topic?

CMN are caused by postzygotic mutations in the gene NRAS in the majority of cases, classifying it within the group of mosaic RASopathies.

Other germline and mosaic RASopathies are known to have growth and hormonal abnormalities.

No studies have been done on growth or endocrinology in children with CMN.

What does this study add?

Average body mass index increases markedly with age compared with the normal population; this is due to increased adiposity, and can be associated with insulin insensitivity.

Premature thelarche variant and persistent undescended testes are not infrequent findings, but puberty appears to develop normally.

Both fat and muscle mass can be reduced in areas underlying large naevi, resulting in asymmetry.

Linked Comment:Millington, Br J Dermatol 2015; 173: 1366–67.

Ulcerative colitis outpatient management: development and evaluation of tools to support primary care practitioners

BACKGROUND

Current models of care for ulcerative colitis (UC) across healthcare systems are inconsistent with a paucity of existing guidelines or supportive tools for outpatient management.

AIMS

This study aimed to produce and evaluate evidence-based outpatient management tools for UC to guide primary care practitioners and patients in clinical decision-making.

METHODS

Three tools were developed after identifying current gaps in the provision of healthcare services for patients with UC at a Clinical Insights Meeting in 2013. Draft designs were further refined through consultation and consolidation of feedback by the steering committee. Final drafts were developed following feasibility testing in three key stakeholder groups (gastroenterologists, general practitioners and patients) by questionnaire. The tools were officially launched into mainstream use in Australia in 2014.

RESULTS

Three quarters of all respondents liked the layout and content of each tool. Minimal safety concerns were aired and those, along with pieces of information that were felt to be omitted, that were reviewed by the steering committee and incorporated into the final documents. The majority (over 80%) of respondents felt that the tools would be useful and would improve outpatient management of UC.

CONCLUSION

Evidence-based outpatient clinical management tools for UC can be developed. The concept and end-product have been well received by all stakeholder groups. These tools should support non-specialist clinicians to optimise UC management and empower patients by facilitating them to safely self-manage and identify when medical support is needed.