Improving the capacity of researchers and bereaved parents to co-design and translate stillbirth research together

BACKGROUND

Working with bereaved parents in co-designed stillbirth research, policy and practice is essential to improving care and outcomes.

PROBLEM

Effective parent engagement is often lacking. This may be due to bereaved parents not feeling adequately and appropriately supported to be involved.

AIM

To consult bereaved parents with the aim to understand their experiences, attitudes, and needs around involvement in stillbirth research and gain feedback about the usefulness and appropriateness of a proposed co-designed guide to support their involvement, including content and design aspects of this resource.

METHODS

An online co-designed survey was disseminated via Australian parent support organisations social media in August 2022.

FINDINGS

All 90 respondents were bereaved parents, 94% (n = 85) were female. Two-thirds (67%, n = 60) had never participated in stillbirth research, 80% (n = 72) agreed involvement of bereaved parents in research was important or extremely important and 81% (n = 73) were interested in future research involvement. Common motivations for involvement were wanting to leave a legacy for their baby and knowing research outcomes. Common barriers included not having been asked to participate or not knowing how. Most (89%, n = 80) agreed the proposed guide would be useful. Highly valued topics were the importance of bereaved parents' voices in stillbirth research and how they can make a difference.

CONCLUSION

The majority of bereaved parents we surveyed want to be involved in stillbirth research and would value a resource to support this. The proposed concept and content for a co-designed guide to aid engagement was well supported.

Intra-Operative Radiotherapy (IORT) in Breast Conserving Therapy in Early-Stage Breast Cancer and DCIS

PURPOSE/OBJECTIVE(S)

Initial breast intra-operative radiotherapy (IORT) results in clinical trials were encouraging though with longer follow up, increased local recurrences have been reported compared with whole breast radiation or other partial breast radiation including accelerated partial breast irradiation (APBI) methods. The goal of the study is to report our prospective single institution IORT breast study outcomes of local recurrence (LR) including true recurrence and breast elsewhere failures, breast cancer specific survival (BCSS), and overall survival (OS) with low energy x-ray IORT in early-stage breast cancer or ductal carcinoma in situ.

MATERIALS/METHODS

A total of 480 patients with early-stage breast cancer or DCIS were prospectively enrolled in an IRB approved single institution trial and treated with low energy X-ray IORT 20 Gy at time of breast-conserving surgery. Eligibility criteria included ≥ 45 years of age with unifocal tumors < 3 cm deemed candidates for partial mastectomy. Supplemental external beam radiation was recommended for patients with high-risk surgical pathology including multifocal disease, positive nodes, close margins < 2 mm, or lymphovascular invasion. Ipsilateral breast tumor recurrences were classified as true recurrence versus elsewhere failure by location and histology: same/different quadrant and similar/different histology. Kaplan-Meier methods were used to estimate survival probabilities across time.

RESULTS

Median age of enrolled patients was 64 years with the majority of patients having favorable phenotype with 94% ER+ and 93% Her-2 - disease. 110 patients (23%) had supplemental EBRT delivered; 103 to the whole breast and 7 to the breast and regional nodes. At a median follow up of 73 months (range 17 - 131 months), there were 23 (4.8%) ipsilateral breast tumor recurrences, of which 9 were true recurrences (1.9%) and 14 elsewhere failures (2.9%). One patient with true recurrence and 3 patients with elsewhere breast failures synchronously presented with clinical or radiographic regional node involvement. Seven patient developed contralateral breast cancer and 8 patients developed distant metastases during the follow-up period. There were 2 breast cancer related deaths. At 6-years, overall survival rate was 96.8% and breast cancer specific survival was 98.7%.

CONCLUSION

Our study outcomes reflect similar outcomes as other reported IORT studies with electron or low energy X-ray in breast cancer, with higher risk of local failure than historical whole breast and other partial breast radiation techniques. This supports current radiation society guidelines for IORT monotherapy for breast cancer to be optimally considered in the context of prospective clinical trials.

Cognitive Behavioral Immersion for Substance Use Disorders: A Feasibility and Pilot Study of a Peer-Based Coaching Program in the Metaverse

Introduction: Cognitive Behavioral Immersion (CBI) is a novel cognitive-behavioral skills program delivered by lay coaches in the metaverse through immersive virtual reality technology. Objectives: The objective for this study was to run a feasibility and pilot study of CBI for individuals in recovery from a substance use disorder. Methods: Data from 48 participants were used and program usage was assessed. Participants were asked to complete questionnaires assessing affect, perceived online social support, and group therapy alliance throughout their participation in the program. Structured qualitative interviews were also conducted with a subset of participants (n = 11) to understand the feasibility of the novel program. Results: Participants experienced a significant increase in their positive affect and non-significant decrease in their negative affect during their most recently attended session. Participants also experienced a nonsignificant increase in online social support across their participation in the program. Structured qualitative interviews revealed eight primary themes, including both advantages (community, psychoeducational impact, immersion, comparability with other interventions, coping in the pandemic, and anonymity) and areas of improvement (challenges and technological usability) of the program. Conclusion: This study provides preliminary support for the feasibility and potential effects of CBI and its incorporation of lay coaches to lead cognitive-behavioral skills groups in the metaverse. Future research is encouraged to examine the feasibility and efficacy of this program for a broader array of clinical presentations.

Examining Predictors of Depression and Anxiety Symptom Change in Cognitive Behavioral Immersion: Observational Study

BACKGROUND

Depressive and anxiety disorders are the most common mental disorders, and there is a critical need for effective, affordable, and accessible interventions. Cognitive Behavioral Immersion (CBI) is a novel group-based cognitive behavioral skills training program delivered by lay coaches in the metaverse that can be accessed through various modalities including virtual reality (VR) head-mounted displays or flat-screen devices. Combining its ability to offer empirically supported therapy skills in a digital setting that can still facilitate interpersonal variables (eg, working alliance and sense of social support) with the aid of lay coaches, CBI has the potential to help fill this critical need.

OBJECTIVE

This study had 2 primary aims. First, we aimed to examine changes in depression and anxiety symptoms in a sample of individuals who participated in CBI. Second, we aimed to examine 2 interpersonal process variables (working alliance and web-based social support) as predictors of symptom changes. We predicted CBI participants would experience depression and anxiety symptom improvements and that such improvements would be associated with an increase in both interpersonal process variables.

METHODS

The study sample consists of 127 participants who endorsed clinical levels of depression or anxiety symptoms during their first CBI session and attended at least 2 sessions. Participants were asked to complete self-report measures of depression symptoms, anxiety symptoms, alliance, and web-based social support throughout their participation in CBI.

RESULTS

Repeated measures ANOVAs determined that depression and anxiety symptom scores differed significantly across sessions (Ps<.01). We also found participants' web-based social support predicted improvement in depression symptoms (P=.01), but neither the alliance nor web-based social support predicted change in anxiety symptoms (Ps>.05). We also observed a significant difference in anxiety symptoms between participants who used a VR head-mounted display to access CBI and those who did not, such that participants who used VR head-mounted displays endorsed lower anxiety symptoms than those who did not at nearly every session (P=.04).

CONCLUSIONS

Participation in CBI is associated with both depression and anxiety symptom improvement. Web-based social support may play an important role in fostering changes in depression symptoms. Future studies are encouraged to continue examining the process of change in CBI with special attention paid to methods that can elucidate causal mechanisms of change.

Crevasse refreezing and signatures of retreat observed at Kamb Ice Stream grounding zone

Ice streams flowing into Ross Ice Shelf are presently responsible for around 10% of the mass flux from West Antarctica, with the noteworthy exception of Kamb Ice Stream, which stagnated in the late 1800s. The subsequent reduction in ice supply led to grounding-line retreat at the coastal margin where Kamb transitions into the floating Ross Ice Shelf. Grounding-line migration is linked to broader changes in ice-sheet mass balance and sea level, but our understanding of related ice, ocean and seafloor interactions is limited by the difficulty in accessing these remote regions. Here we report in situ observations from an underwater vehicle deployed at Kamb that show how fine-scale variability in ice and ocean structure combine to influence a diversity of ice-ocean interactions. We found a stratified water column within a tenth of a degree of freezing at the ice base and mapped basal crevasses with supercooled water and active marine ice formation. At the seafloor, we interpret parallel ridges as crevasse impressions left as the ice lifted off during grounding-line retreat. These observations from a recently ungrounded sub-shelf environment illuminate both the geomorphological signatures of past grounding-line retreat and the fine-scale sensitivity of ongoing ice-ocean interactions to ice topography.

Screening two biodegradable polymers in enhanced efficiency fertiliser formulations reveals the need to prioritise performance goals

Enhanced efficiency fertilisers (EEF) may reduce nitrogen (N) losses and improve uptake efficiency through synchronising N release with in-season plant requirements. We hypothesised that EEF formed via matrix encapsulation in biodegradable polymers will improve N use efficiency when compared to conventional urea fertiliser. This hypothesis was investigated for two biodegradable polymer matrices: polyhydroxyalkanoate (PHA), containing 11.6% urea (by mass), and polybutylene-adipate-co-terephthalate (PBAT), containing either 19.4 or 32.7% urea; and two contrasting soil types: sand and clay. Nitrogen availability and form was investigated under leaching conditions (water) with a growth accelerator pot experiment involving a horticultural crop and novel non-destructive three-dimensional scanning to measure in-season biomass development. The PBAT 32.7% formulation enabled greater above ground biomass production at both 50 and 100 kg N ha^-1 equivalent application rates compared to conventional urea. For the sandy soil, plant scanning indicated that improved uptake performance with PBAT 32.7% was probably the result of greater N availability after 25 days than for conventional urea. Two of the encapsulated formulations (PHA and PBAT 19.4%) tended to decrease nitrogen leaching losses relative to urea (P < 0.05 for the red clay soil). However, decreased N leaching loss was accompanied by poorer N uptake performance, indicative of N being less available in these biopolymer formulations. A snapshot of nitrous oxide emissions collected during peak nitrate concentration (prior to planting and leaching) suggested that the biopolymers promoted N loss via gaseous emission relative to urea in the sandy soil (P < 0.05), and carbon dioxide emissions data suggested that biopolymer-carbon increased microbial activity (P < 0.1). Controlled testing of N release in water was a poor predictor of biomass production and leaching losses. The diverse behaviours of the tested formulations present the potential to optimise biopolymers and their N loadings by taking into account soil and environmental factors that influence the efficient delivery of N to target crops. The greater N uptake efficiency demonstrated for the PBAT 32.7% formulation confirms our hypothesis that matrix encapsulation can enable better synchronisation of N release with crop requirements and decrease leaching losses.

Expression of type I interferon-associated genes at antiretroviral therapy interruption predicts HIV virological rebound

Although certain individuals with HIV infection can stop antiretroviral therapy (ART) without viral load rebound, the mechanisms under-pinning 'post-treatment control' remain unclear. Using RNA-Seq we explored CD4 T cell gene expression to identify evidence of a mechanism that might underpin virological rebound and lead to discovery of associated biomarkers. Fourteen female participants who received 12 months of ART starting from primary HIV infection were sampled at the time of stopping therapy. Two analysis methods (Differential Gene Expression with Gene Set Enrichment Analysis, and Weighted Gene Co-expression Network Analysis) were employed to interrogate CD4+ T cell gene expression data and study pathways enriched in post-treatment controllers versus early rebounders. Using independent analysis tools, expression of genes associated with type I interferon responses were associated with a delayed time to viral rebound following treatment interruption (TI). Expression of four genes identified by Cox-Lasso (ISG15, XAF1, TRIM25 and USP18) was converted to a Risk Score, which associated with rebound (p < 0.01). These data link transcriptomic signatures associated with innate immunity with control following stopping ART. The results from this small sample need to be confirmed in larger trials, but could help define strategies for new therapies and identify new biomarkers for remission.

Childhood DNA methylation as a marker of early life rapid weight gain and subsequent overweight

BACKGROUND

High early postnatal weight gain has been associated with childhood adiposity; however, the mechanism remains unknown. DNA methylation is a hypothesised mechanism linking early life exposures and subsequent disease. However, epigenetic changes associated with high early weight gain have not previously been investigated. Our aim was to investigate the associations between early weight gain, peripheral blood DNA methylation, and subsequent overweight/obese. Data from the UK Avon Longitudinal study of Parents and Children (ALSPAC) cohort were used to estimate associations between early postnatal weight gain and epigenome-wide DNA CpG site methylation (Illumina 450 K Methylation Beadchip) in blood in childhood (n = 125) and late adolescence (n = 96). High weight gain in the first year (a change in weight z-scores > 0.67), both unconditional (rapid weight gain) and conditional on birthweight (rapid thrive), was related to individual CpG site methylation and across regions using the meffil pipeline, with and without adjustment for cell type proportions, and with 5% false discovery rate correction. Variation in methylation at high weight gain-associated CpG sites was then examined with regard to body composition measures in childhood and adolescence. Replication of the differentially methylated CpG sites was sought using whole-blood DNA samples from 104 children from the UK Southampton Women's Survey.

RESULTS

Rapid infant weight gain was associated with small (+ 1% change) increases in childhood methylation (age 7) for two distinct CpG sites (cg01379158 (NT5M) and cg11531579 (CHFR)). Childhood methylation at one of these CpGs (cg11531579) was also higher in those who experienced rapid weight gain and were subsequently overweight/obese in adolescence (age 17). Rapid weight gain was not associated with differential DNA methylation in adolescence. Childhood methylation at the cg11531579 site was also suggestively associated with rapid weight gain in the replication cohort.

CONCLUSIONS

This study identified associations between rapid weight gain in infancy and small increases in childhood methylation at two CpG sites, one of which was replicated and was also associated with subsequent overweight/obese. It will be important to determine whether loci are markers of early rapid weight gain across different, larger populations. The mechanistic relevance of these differentially methylated sites requires further investigation.

P1485Left atrial reservoir function is associated with major adverse cardiac events in patients undergoing transarterial valve implantation for isolated severe aortic stenosis

Background

Left atrial (LA) reservoir function as measured by LA global longitudinal strain (LAGS) is an independent predictor of left ventricular (LV) performance and has prognostic value.

Purpose

To evaluate by speckle tracking echocardiography (STE), LAGS and other myocardial deformation indices changes after transarterial valve implantation (TAVI) for severe isolated aortic stenosis (AS) in relation to the outcome measures.

Methods

Of 995 pts who underwent TAVI at our Institution between 2017–18, 120 (age = 82.8±7.7 years, 74% female, AVAi = 0.37±0.09 cm2/m2, LVEF = 61.6±11.3%, no > than 2+ mitral or aortic regurgitation, all in NSR) underwent 2-D echocardiography and STE, pre (21±34 days) and post (16±27 days) TAVI. LAGS was measured at QRS onset, and LV global longitudinal strain (LVGS) and RV free wall strain were recorded. The velocity index = peak vel LVOT/AV. Phillips IE 33 scanners (frame rates 60–80 Hz) were used and one observer analyzed data on QLAB software. The median follow-up was 208 days (range 20–763). The outcome variable was a composite of death, atrial fibrillation and hospitalization for heart failure (MACE). Univariate and multivariable logistic regression were used to determine independent predictors of LA, LV and RV free wall global strain changes (covariates; age, sex, BSA, LVEF, systolic blood pressure, LA volume index) and, separately, for predictors of MACE (covariates; age, sex, AVA index, LVEF and E/e'). Intra- and interclass correlation coefficients (ICC) were calculated.

Results

The intra- and inter-observer ICC was 0.70–0.90 and 0.90–0.95, respectively. In the absence of LA volume change, LAGS improved post TAVI in 54% of pts. Overall, mean change was 2.2±11.6% (95% CI; 0.05, 4.3) and it was significantly associated in multivariable analysis with RV free wall strain (OR=2.7, 95% CI; 1.2, 6), velocity index (OR=0.4, 95% CI; 0.2, 1), LVEF (OR= 0.3, 95% CI; 0.2, 0.8) and LVGS (OR=3.8, 95% CI; 1.4, 10), yielding together an AUC of 0.90. LVGS improved in 64% of pts by −2.8±7.5%, (95% CI: −4.2, −1.5) and the velocity index independently predicted the LVGS change (OR = 0.6; 95% CI: 0.4, 0.9). The other deformation indices did not significantly change. At follow-up, there were 6 hospitalizations for heart failure, 5 atrial fibrillation events and 6 deaths. At multivariable logistic regression analysis, post TAVI LAGS was the only variable independently predicting MACE (OR (in units of 1%) = 0.90, 95% CI; 0.82, 0.98), estimating that a 1% increase in post-LAGS decreases the likelihood of MACE by 10%.

Conclusions

1. There was no relationship between LA systolic volume and LAGS change after TAVI. 2. Within a month after the procedure, LAGS improves in less than half of pts and is directly associated with both ventricles systolic function and AS severity. 3. At a median of 9 months after TAVI, post procedural LAGS is an independent predictor of MACE and could be used in the risk stratification of such pts.

Sorbents can tailor nitrogen release from organic wastes to match the uptake capacity of crops

Delivering nutrients from mineral or organic fertilizers out of synchrony with crop uptake causes inefficiencies and pollution. We explore methodologies for evaluating sorbents as additives to organic agricultural wastes to retain nitrogen in an exchangeable form and deliver at rates that approximate the uptake capacity of roots. Focussing on ammonium (NH₄⁺) as the main inorganic nitrogen form in the studied wastes (sugarcane mill mud, poultry litter), we tested geo-sorbents and biochar for their ability to retain NH₄⁺. Sorption capacity was ranked palagonite < bentonite, biochar, vermiculite < chabazite, clinoptilolite (5.7 to 24.3 mg NH₄⁺ g^-1 sorbent). Sorbent-waste formulations were analysed for sorption capacity, leaching and fluxes of NH₄⁺. Ammonium-sorption capacity broadly translated to sorbent-waste formulations with clinoptilolite conferring the strongest NH₄⁺ attenuation (80%), and palagonite the lowest (7%). A 1:1 ratio of sorbent:waste achieved stronger sorption than a 0.5:1 ratio, and similar sorption as a 1:1.5 ratio. In line with these results, clinoptilolite-amended wastes had the lowest in situ NH₄⁺ fluxes, which exceeded the NH₄⁺ uptake capacity (I_max) of sugarcane and sorghum roots 9 to 84-fold, respectively. Less efficient sorbent-waste formulations and un-amended wastes exceeded I_max of crop roots up to 274-fold. Roots preferentially colonized stronger sorbent-waste formulations and avoided weaker ones, suggesting that lower NH₄⁺ fluxes generate a more favourable growth environment. This study contributes methodologies to identify suitable sorbents to formulate organic wastes as next-generation fertilizers with view of a crop's nutrient physiology. Efficient re-purposing of wastes can improve nutrient use efficiency in agriculture and support the circular nutrient economy.

How to improve threatened species management: An Australian perspective

Targeted threatened species management is a central component of efforts to prevent species extinction. Despite the development of a range of management frameworks to improve conservation outcomes over the past decade, threatened species management is still commonly characterised as ad hoc. Although there are notable successes, many management programs are ineffective, with relatively few species experiencing improvements in their conservation status. We identify underlying factors that commonly lead to ineffective and inefficient management. Drawing attention to some of the key challenges, and suggesting ways forward, may lead to improved management effectiveness and better conservation outcomes. We highlight six key areas where improvements are needed: 1) stakeholder engagement and communication; 2) fostering strong leadership and the development of achievable long-term goals; 3) knowledge of target species' biology and threats, particularly focusing on filling knowledge gaps that impede management, while noting that in many cases there will be a need for conservation management to proceed initially despite knowledge gaps; 4) setting objectives with measurable outcomes; 5) strategic monitoring to evaluate management effectiveness; and 6) greater accountability for species declines and failure to recover species to ensure timely action and guard against complacency. We demonstrate the importance of these six key areas by providing examples of innovative approaches leading to successful species management. We also discuss overarching factors outside the realm of management influence that can help or impede conservation success. Clear recognition of factors that make species' management more straightforward - or more challenging - is important for setting realistic management objectives, outlining strategic action, and prioritising resources. We also highlight the need to more clearly demonstrate the benefit of current investment, and communicate that the risk of under-investment is species extinctions. Together, improvements in conservation practice, along with increased resource allocation and re-evaluation of the prioritisation of competing interests that threaten species, will help enhance conservation outcomes for threatened species.

The impact of immunoglobulin in acute HIV infection on the HIV reservoir: a randomized controlled trial

OBJECTIVES

Antiretroviral therapy (ART) during acute HIV infection (AHI) restricts the HIV reservoir, but additional interventions are necessary to induce a cure. Intravenous immunoglobulin (IVIG) is not HIV-specific but is safe and temporarily reduces the HIV reservoir in chronic HIV infection. We present a randomized controlled trial to investigate whether IVIG plus ART in AHI reduces the HIV reservoir and immune activation compared with ART alone.

METHODS

Ten men with AHI (Fiebig II-IV) initiated ART (tenofovir, entricitabine, ritonavir boosted darunavir and raltegravir) at HIV-1 diagnosis and were randomized to ART alone or ART plus 5 days of IVIG, once virally suppressed (week 19). Blood samples were evaluated for viral reservoir, immune activation, immune exhaustion and microbial translocation. Flexible sigmoidoscopy was performed at weeks 19, 24 and 48, and gut proviral DNA and cell numbers determined.

RESULTS

IVIG was well tolerated and no viral blips (> 50 HIV-1 RNA copies/mL) occurred during IVIG therapy. From baseline to week 48, total HIV DNA in peripheral blood mononuclear cells (PBMCs) (cases: -3.7 log₁₀ copies/10⁶ CD4 cells; controls: -3.87 log₁₀ copies/10⁶ CD4 cells) declined with no differences observed between the groups (P = 0.49). Declines were observed in both groups from week 19 to week 48 in total HIV DNA in PBMCs (P = 0.38), serum low copy RNA (P = 0.57) and gut total HIV DNA (P = 0.55), but again there were no significant differences between arms. Biomarkers of immune activation, immune exhaustion and microbial translocation and the CD4:CD8 ratio were similar between arms for all comparisons.

CONCLUSIONS

Although safe, IVIG in AHI did not impact total HIV DNA, immune function or microbial translocation in peripheral blood or gut tissue.

The epic project. Updating the evidence-base for national evidence-based guidelines for preventing healthcare-associated infections in NHS hospitals in England: a report with recommendations

The evidence underpinning infection prevention and control guidelines requires updating at regular intervals as advances in technology and new research findings may influence guideline recommendations. The evidence-base for national guidelines published in 20011 for preventing healthcare-associated infections in hospitals in England has recently been updated using systematic review methods. A critical assessment of the updated evidence indicates that the current guidelines remain robust, relevant and appropriate, but that adjustments need to be made to some guideline recommendations. Periodically updating the evidence base and making necessary adjustments to guideline recommendations is essential, in order to maintain their validity and authority.

Crying as communication in psychotherapy: The influence of client and therapist attachment dimensions and client attachment to therapist on amount and type of crying

Nelson (2005) associated 3 types of crying (inhibited, protest, despair) with 3 dimensions of attachment (avoidant, anxious, and secure). To test this theory, trained judges rated the intensity of inhibition, protest, and despair in 347 crying episodes for 40 clients and 14 therapists in 1,074 psychotherapy sessions. Crying occurred once out of every 7 sessions, and usually was characterized by protest or inhibition. Pre-therapy attachment dimensions of both therapist and client influenced crying. Therapists with high attachment avoidance had clients who cried frequently but less over time, whereas therapists with high attachment anxiety had clients who cried with more protest over time. Clients with high attachment anxiety initially cried with more protest and inhibition, but decreased over time, whereas clients with low attachment anxiety increased protest over time. Throughout the course of psychotherapy, therapists who were seen by their clients as establishing a secure attachment elicited more overall crying and a higher intensity of protest, whereas therapists who were seen by their clients as establishing insecure attachments had clients who cried less. Clients who established a secure or avoidant relationship with their therapists, relative to other clients of that therapist, cried infrequently and with inhibition, whereas clients who established a preoccupied relationship cried relatively often. Changes are suggested for Nelson's (2005) typology.

The effect of a period of intensive exercise on the isoform test to detect growth hormone doping in sports

OBJECTIVE

The major objective of this study was to investigate the effects of several days of intense exercise on growth hormone (hGH) testing using the World Anti-Doping Agencies hGH isoform differential immunoassays. Additionally the effects of circadian variation and exercise type on the isoform ratios were also investigated.

STUDY DESIGN

15 male athletes performed a simulated nine day cycling stage race. Blood samples were collected twice daily over a period of 15 days (stage race+three days before and after). hGH isoforms were analysed by the official WADA immunoassays (CMZ Assay GmbH).

RESULTS

All measured isoform ratios were far below the WADA decision limits for an adverse analytical finding. Changes in the isoform ratios could not be clearly connected to circadian variation, exercise duration or intensity.

CONCLUSIONS

The present study demonstrates that the hGH isoform ratios are not significantly affected by exercise or circadian variation. We demonstrated that heavy, long term exercise does not interfere with the decision limits for an adverse analytical finding.

IL-10 produced by trophoblast cells inhibits phagosome maturation leading to profound intracellular proliferation of Salmonella enterica Typhimurium

INTRODUCTION

Salmonella enterica Typhimurium (ST) is a phagosomal pathogen that can infect placental trophoblast cells leading to abortion and severe maternal illness. It is unclear how the trophoblast cells promote profound bacterial proliferation.

METHODS

The mechanism of internalization, intracellular growth and phagosomal biogenesis in ST-infected human epithelial (HeLa), macrophage (THP-1) and trophoblast-derived cell lines (JEG-3, BeWo and HTR-8) was studied. Specific inhibitors were used to block bacterial internalization. Phagosomal maturation was determined by confocal microscopy, Western-blotting and release of lysosomal β-galactosidase by infected cells. Bacterial colony forming units were determined by plating infected cell lysates on agar plates.

RESULTS

ST proliferated minimally in macrophages but replicated profoundly within trophoblast cells. The ST-ΔinvA (a mutant of Salmonella pathogenicity island-1 gene effector proteins) was unable to infect epithelial cells, but was internalized by scavenger receptors on trophoblasts and macrophages. However, ST was contrastingly localized in early (Rab5⁺) or late (LAMP1⁺) phagosomes within trophoblast cells and macrophages respectively. Furthermore trophoblast cells (unlike macrophages) did not exhibit phagoso-lysosomal fusion. ST-infected macrophages produced IL-6 whereas trophoblast cells produced IL-10. Neutralizing IL-10 in JEG-3 cells accelerated phagolysomal fusion and reduced proliferation of ST. Placental bacterial burden was curtailed in vivo in anti-IL-10 antibody treated and IL-10-deficient mice.

DISCUSSION

Macrophages phagocytose but curtail intracellular replication of ST in late phagosomes. In contrast, phagocytosis by trophoblast cells results in an inappropriate cytokine response and proliferation of ST in early phagosomes.

CONCLUSION

IL-10 production by trophoblast cells that delays phagosomal maturation may facilitate proliferation of pathogens in placental cells.

Carers' perspectives of a weight loss intervention for adults with intellectual disabilities and obesity: a qualitative study

BACKGROUND

To date, no studies have explored the role of carers in supporting adults with intellectual disabilities (ID) and obesity during a weight loss intervention. The present study explored perceptions of carers supporting adults with ID, as they participated in a 6-month multi-component weight loss intervention (TAKE 5).

METHODS

Semi-structured interviews were used to explore the experiences of 24 carers. The transcripts were analysed qualitatively using thematic analysis.

RESULTS

Three themes emerged from the analysis: carers' perceptions of participants' health; barriers and facilitators to weight loss; and carers' perceptions of the weight loss intervention. Data analysis showed similarities between the experiences reported by the carers who supported participants who lost weight and participants who did not. Lack of sufficient support from people from the internal and external environment of individuals with ID and poor communication among carers, were identified as being barriers to change. The need for accessible resources tailored to aid weight loss among adults with ID was also highlighted.

CONCLUSION

This study identified specific facilitators and barriers experienced by carers during the process of supporting obese adults with ID to lose weight. Future research could utilise these findings to inform appropriate and effective weight management interventions for individuals with ID.

The atmospheric chemistry of trace gases and particulate matter emitted by different land uses in Borneo

We report measurements of atmospheric composition over a tropical rainforest and over a nearby oil palm plantation in Sabah, Borneo. The primary vegetation in each of the two landscapes emits very different amounts and kinds of volatile organic compounds (VOCs), resulting in distinctive VOC fingerprints in the atmospheric boundary layer for both landscapes. VOCs over the Borneo rainforest are dominated by isoprene and its oxidation products, with a significant additional contribution from monoterpenes. Rather than consuming the main atmospheric oxidant, OH, these high concentrations of VOCs appear to maintain OH, as has been observed previously over Amazonia. The boundary-layer characteristics and mixing ratios of VOCs observed over the Borneo rainforest are different to those measured previously over Amazonia. Compared with the Bornean rainforest, air over the oil palm plantation contains much more isoprene, monoterpenes are relatively less important, and the flower scent, estragole, is prominent. Concentrations of nitrogen oxides are greater above the agro-industrial oil palm landscape than over the rainforest, and this leads to changes in some secondary pollutant mixing ratios (but not, currently, differences in ozone). Secondary organic aerosol over both landscapes shows a significant contribution from isoprene. Primary biological aerosol dominates the super-micrometre aerosol over the rainforest and is likely to be sensitive to land-use change, since the fungal source of the bioaerosol is closely linked to above-ground biodiversity.