Structural variation and DNA methylation shape the centromere-proximal meiotic crossover landscape in Arabidopsis

BACKGROUND

Centromeres load kinetochore complexes onto chromosomes, which mediate spindle attachment and allow segregation during cell division. Although centromeres perform a conserved cellular function, their underlying DNA sequences are highly divergent within and between species. Despite variability in DNA sequence, centromeres are also universally suppressed for meiotic crossover recombination, across eukaryotes. However, the genetic and epigenetic factors responsible for suppression of centromeric crossovers remain to be completely defined.

RESULTS

To explore the centromere-proximal meiotic recombination landscape, we map 14,397 crossovers against fully assembled Arabidopsis thaliana (A. thaliana) genomes. A. thaliana centromeres comprise megabase satellite repeat arrays that load nucleosomes containing the CENH3 histone variant. Each chromosome contains a structurally polymorphic region of ~3-4 megabases, which lack crossovers and include the satellite arrays. This polymorphic region is flanked by ~1-2 megabase low-recombination zones. These recombination-suppressed regions are enriched for Gypsy/Ty3 retrotransposons, and additionally contain expressed genes with high genetic diversity that initiate meiotic recombination, yet do not crossover. We map crossovers at high-resolution in proximity to CEN3, which resolves punctate centromere-proximal hotspots that overlap gene islands embedded in heterochromatin. Centromeres are densely DNA methylated and the recombination landscape is remodelled in DNA methylation mutants. We observe that the centromeric low-recombining zones decrease and increase crossovers in CG (met1) and non-CG (cmt3) mutants, respectively, whereas the core non-recombining zones remain suppressed.

CONCLUSION

Our work relates the genetic and epigenetic organization of A. thaliana centromeres and flanking pericentromeric heterochromatin to the zones of crossover suppression that surround the CENH3-occupied satellite repeat arrays.

Transition to Self-compatibility Associated With Dominant S-allele in a Diploid Siberian Progenitor of Allotetraploid Arabidopsis kamchatica Revealed by Arabidopsis lyrata Genomes

A transition to selfing can be beneficial when mating partners are scarce, for example, due to ploidy changes or at species range edges. Here, we explain how self-compatibility evolved in diploid Siberian Arabidopsis lyrata, and how it contributed to the establishment of allotetraploid Arabidopsis kamchatica. First, we provide chromosome-level genome assemblies for two self-fertilizing diploid A. lyrata accessions, one from North America and one from Siberia, including a fully assembled S-locus for the latter. We then propose a sequence of events leading to the loss of self-incompatibility in Siberian A. lyrata, date this independent transition to ∼90 Kya, and infer evolutionary relationships between Siberian and North American A. lyrata, showing an independent transition to selfing in Siberia. Finally, we provide evidence that this selfing Siberian A. lyrata lineage contributed to the formation of the allotetraploid A. kamchatica and propose that the selfing of the latter is mediated by the loss-of-function mutation in a dominant S-allele inherited from A. lyrata.

Cycles of satellite and transposon evolution in Arabidopsis centromeres

Centromeres are critical for cell division, loading CENH3 or CENPA histone variant nucleosomes, directing kinetochore formation and allowing chromosome segregation^1,2. Despite their conserved function, centromere size and structure are diverse across species. To understand this centromere paradox^3,4, it is necessary to know how centromeric diversity is generated and whether it reflects ancient trans-species variation or, instead, rapid post-speciation divergence. To address these questions, we assembled 346 centromeres from 66 Arabidopsis thaliana and 2 Arabidopsis lyrata accessions, which exhibited a remarkable degree of intra- and inter-species diversity. A. thaliana centromere repeat arrays are embedded in linkage blocks, despite ongoing internal satellite turnover, consistent with roles for unidirectional gene conversion or unequal crossover between sister chromatids in sequence diversification. Additionally, centrophilic ATHILA transposons have recently invaded the satellite arrays. To counter ATHILA invasion, chromosome-specific bursts of satellite homogenization generate higher-order repeats and purge transposons, in line with cycles of repeat evolution. Centromeric sequence changes are even more extreme in comparison between A. thaliana and A. lyrata. Together, our findings identify rapid cycles of transposon invasion and purging through satellite homogenization, which drive centromere evolution and ultimately contribute to speciation.

Extensive sequence duplication in Arabidopsis revealed by pseudo-heterozygosity

BACKGROUND

It is apparent that genomes harbor much structural variation that is largely undetected for technical reasons. Such variation can cause artifacts when short-read sequencing data are mapped to a reference genome. Spurious SNPs may result from mapping of reads to unrecognized duplicated regions. Calling SNP using the raw reads of the 1001 Arabidopsis Genomes Project we identified 3.3 million (44%) heterozygous SNPs. Given that Arabidopsis thaliana (A. thaliana) is highly selfing, and that extensively heterozygous individuals have been removed, we hypothesize that these SNPs reflected cryptic copy number variation.

RESULTS

The heterozygosity we observe consists of particular SNPs being heterozygous across individuals in a manner that strongly suggests it reflects shared segregating duplications rather than random tracts of residual heterozygosity due to occasional outcrossing. Focusing on such pseudo-heterozygosity in annotated genes, we use genome-wide association to map the position of the duplicates. We identify 2500 putatively duplicated genes and validate them using de novo genome assemblies from six lines. Specific examples included an annotated gene and nearby transposon that transpose together. We also demonstrate that cryptic structural variation produces highly inaccurate estimates of DNA methylation polymorphism.

CONCLUSIONS

Our study confirms that most heterozygous SNP calls in A. thaliana are artifacts and suggest that great caution is needed when analyzing SNP data from short-read sequencing. The finding that 10% of annotated genes exhibit copy-number variation, and the realization that neither gene- nor transposon-annotation necessarily tells us what is actually mobile in the genome suggests that future analyses based on independently assembled genomes will be very informative.

Modeling gait score of broiler chicken via production and behavioral data

Lameness in broilers may be associated with pain and is considered a major broiler production and welfare concern. Manual gait score assessment in commercial broiler houses is discrete, time-consuming, and laborious. As such, automatic methods for broiler gait score assessment are urgently needed. The objective of this study was to identify the relation of broiler gait score with several productions and behavioral metrics (bird BW, age, activity, and distribution), and establish three gait score prediction models for automatic gait score estimations in broiler farms with automatic weighing systems, camera systems, or both. Sixteen pens were used to rear Cobb 500 and Ross 708 broilers for eight and nine weeks, respectively (eight pens/strain, 12 birds/pen). The gait scores of all birds were assessed weekly by trained assessors following a six-point (0-5) scoring protocol from the third week. The pen's average BW was measured weekly. Top-view cameras were installed to continuously record videos of broilers in all 16 pens. Images were extracted from video clips (10 min/hour) during a 16-hour light period to determine the activity index and distribution index through image processing. The gait score was positively correlated with BW (R² = 0.97 for Cobb and R² = 0.96 for Ross), while negatively correlated with activity (R² = 0.78 for Cobb and R² = 0.73 for Ross). The three models showed high accuracies in predicting broiler gait score based on variables of BW, age, activity index, and distribution index (R² = 0.90-0.91, RMSE = 0.38-0.41). The findings of this study demonstrated the potential of estimating broiler gait score using bird BW, age, activity index, and distribution index. This information will assist in the development of automated gait score assessment systems in broiler production.

Intramedullary, periosteal, and extraskeletal Ewing sarcomas: retrospective study of a series of 126 cases in a reference center

OBJECTIVE

To evaluate the proportion of extraskeletal, periosteal, and intramedullary Ewing sarcomas among musculoskeletal Ewing sarcomas.

MATERIAL AND METHOD

Our single-center retrospective study included patients with musculoskeletal Ewing sarcoma diagnosed between 2005 and 2019 in our pathology center (cases from our adult bone tumor referral center and adult and pediatric cases referred for review). Recurrences, metastases, and visceral Ewing sarcomas were excluded. Intramedullary Ewing sarcomas were defined by involvement of the medullary cavity. Periosteal cases were defined by involvement of the subperiosteal area without extension to the medullary cavity. Extraskeletal cases were defined by the absence of involvement of the bone tissue and the subperiosteal area.

RESULTS

Our series included 126 patients with musculoskeletal Ewing sarcoma, including 118 skeletal Ewing sarcomas (93.7%) and 8 extraskeletal Ewing sarcomas (6.3%). Of the 118 skeletal Ewing sarcomas 112 were intramedullary (88.9%) and 6 were periosteal (4.8%). Extraskeletal Ewing sarcomas were more common in women and in patients older than 40 (p < 0.05).

DISCUSSION

The 6.3% proportion of extraskeletal Ewing sarcoma is lower than the median of 30% estimated from the literature. This difference could be explained by an overestimation of extraskeletal Ewing sarcomas of the chest wall (Askin tumors), an underestimation of periosteal cases confused with extraskeletal cases, and the presence of "Ewing-like" soft tissue sarcomas in previous series. Because of its prognostic and therapeutic impact, the distinction of morphologic subtypes requires the cooperation of experienced radiologists and pathologists.

POS0993 RADIOLOGICAL CERVICAL INVOLVMENT IN ANKYLOSING SPONDYLITIS

Background

Cervical involvement in ankylosing spondylitis (AS) is particularly disabling and has been poorly studied yet. Actual radiologic scoring design to assess disease progression does not provide a comprehensive picture of the cervical involvement in AS. [1] Association with clinical features such as psoriasis are discussed.

Objectives

We aimed to assess radiographic features of cervical involvement in AS and clinico-biological parameters associated with this specific radiographic location.

Methods

Cross-sectional study based on radiographic analysis of a subgroup of patients included in the French BambooSpine cohort, originally designed to study the genetic risk factors of AS structural severity. The analysis was based on patients included in Parisian hospitals to have access to images of the entire spine on the Picture Archiving and Communication System (PACS) shared by all University Hospitals in Paris. A double reading of the images was performed by a rheumatologist/radiologist pair until consensus was reached, to identify syndesmophytes, zygapophyseal joint (ZJ) involvement and posterior ligament structures (PLS) at each cervical level, syndesmophytes in the thoracic region, and ZJ and PLS involvement in the lumbar region.

Results

Of the 113 assessed patients, 101 were men, mean age 53 years (+/- 11 years) with 27 years (+/- 13 years) of disease duration (Table 1). Of those whose HLA B27 status was known, 85% (70/82) were carriers. Among 86 patients with radiological cervical involvement, 83% had syndesmophytes, 86% had ZJ involvement and 24% had PLS involvement. In the cervical region, 13 patients (15%) had zygapophyseal fusion without syndesmophytes. 26/113 patients were completely free of any cervical involvement while 30/113 had a maximal cervical involvement (anterior and posterior). In univariate analyses, HLA-B27 was significantly associated with ZJ involvement at the cervical and lumbar level (p=0.016). Cervical involvement of any type was not associated with psoriasis. Low educational level (not beyond secondary school) was significantly associated with syndesmophytic involvement (p=0.035). There was a non-significant trend for an association between arthritis and ZJ involvement.

Table 1.

Clinical features

Men (n,%)101/11389,4%Age at diagnosis (mean, SD)31,211,68Duration of evolution (mean, SD)27,013,0Smoking ever (n,%)65/11258,0 %Chronic Back Pain (for > 3 months) (n,%)109/11396,5%Chest pain45/11040,9%Buttock pain78/10971,6%Arthritis36/11132,4%Enthesitis38/11233,9%Dactylitis6/1115,4%HLA B2770/8285,4%CRP87/10384,5%X ray sacro-iliitis112/112100%Personnal history -Uveitis41/11336,3% -Inflammatory bowel disease13/11311,5% -Reactive arthritis2/1121,8% -Psoriasis19/11117,1%

Conclusion

Cervical involvement was very frequent (76% of this severe AS population) but not associated with psoriasis, as usually thought. Zygapophyseal involvement was present in 86 % of cases and exclusive in 15 % of cases. This latter radiological form of the disease, i.e. without syndesmophytes, is usually more difficult to diagnose, and should be systematically assessed among AS patients with cervical pain and/or patients with reduced cervical mobility.

References

[1]Wanders AJB, Landewé RBM, Spoorenberg A, et al. What is the most appropriate radiologic scoring method for ankylosing spondylitis? Arthritis & Rheumatism 2004

Disclosure of Interests

None declared

Trait-anger, hostility, and the risk of incident type 2 diabetes and diabetes-related complications: a systematic review of longitudinal studies

Introduction

There is a well-established association between anger, hostility, and an increased risk of cardiovascular disease. Emerging evidence also suggests associations between anger/hostility and type 2 diabetes (T2D), though evidence from longitudinal studies has not yet been synthesized.

Objectives

To systematically review findings from existing prospective cohort studies on trait anger/hostility and the risk of T2D and diabetes-related complications.

Methods

Electronic searches of MEDLINE (PubMed), PsychINFO, Web of Science, and CINAHL were performed for articles/abstracts published up to December 15, 2020. Peer-reviewed longitudinal studies conducted with adult samples, with effect estimates reported for trait anger or hostility and incident T2D or diabetes-related complications, were eligible for inclusion. Risk of bias/study quality was assessed. The review protocol was published a priori in PROSPERO (CRD42020216356) and was in keeping with PRISMA guidelines. Screening for eligibility, data extraction, and quality assessment was conducted by two independent reviewers.

Results

Four studies with a total of 155,146 participants met the inclusion criteria. A narrative synthesis of extracted data was conducted according to the Synthesis Without Meta-Analysis guidelines. While results were mixed, our synthesis suggested a positive association between high trait-anger/hostility and increased risk of incident T2D. No longitudinal studies were identified relating to anger/hostility and incident diabetes-related complications. Geographical locations of the study samples were limited to the USA and Japan.

Conclusions

Further research is needed to investigate whether trait-anger/hostility predicts incident type 2 diabetes after adjustments for potential confounding factors. Longitudinal studies are needed to investigate trait-anger/hostility and the risk of diabetes-related vascular complications.

Disclosure

No significant relationships.

Gradual evolution of allopolyploidy in Arabidopsis suecica

Most diploid organisms have polyploid ancestors. The evolutionary process of polyploidization is poorly understood but has frequently been conjectured to involve some form of 'genome shock', such as genome reorganization and subgenome expression dominance. Here we study polyploidization in Arabidopsis suecica, a post-glacial allopolyploid species formed via hybridization of Arabidopsis thaliana and Arabidopsis arenosa. We generated a chromosome-level genome assembly of A. suecica and complemented it with polymorphism and transcriptome data from all species. Despite a divergence around 6 million years ago (Ma) between the ancestral species and differences in their genome composition, we see no evidence of a genome shock: the A. suecica genome is colinear with the ancestral genomes; there is no subgenome dominance in expression; and transposon dynamics appear stable. However, we find changes suggesting gradual adaptation to polyploidy. In particular, the A. thaliana subgenome shows upregulation of meiosis-related genes, possibly to prevent aneuploidy and undesirable homeologous exchanges that are observed in synthetic A. suecica, and the A. arenosa subgenome shows upregulation of cyto-nuclear processes, possibly in response to the new cytoplasmic environment of A. suecica, with plastids maternally inherited from A. thaliana. These changes are not seen in synthetic hybrids, and thus are likely to represent subsequent evolution.

Developing a smartphone app with UK migrants for UK migrants: lessons learned from focus group work

Background

In 2018, 14% of people living in the UK were born abroad, yet we have a limited understanding of the broader determinants of their health. To address this knowledge gap, the Health on the MovE (HOME) smartphone application (app) study was conceived. Through app-based surveys, the study will examine how risk factors for health and well-being are distributed among migrants and how these vary over time since migration to the UK. There is a lack of research addressing the development of apps for longitudinal data collection in the general population - and we did not find any in migrant groups.

Methods

To better inform the design of the HOME app study, three workshops were held in 2018 and 2019, involving both migrants and App development experts. We used a semi-structured interview schedule focused on five themes: smartphones, apps and research, HOME app wireframe (screen-by-screen review of the app), types of surveys and survey schedules, resource section content, and participant engagement strategies. The participants were purposively sampled to reflect the migrant population arriving in the UK from non-EU countries.

Results

Migrants reported high smartphone use and were positive about the app design and app-based research. Concerns around privacy and data protection were highlighted and limits were suggested for the frequency of surveys and the number of questions used. Mental health was identified as a key topic for research. Participants requested the inclusion of resources concerning asylum claim procedures and immigrant and labour laws. Migrants advised that study recruitment material should clearly state the purpose and scope of the research and requested regular feedback on study outcomes.

Conclusions

The workshops provided important feedback and facilitated the co-production of the HOME app. Overall findings suggest that the study would be both acceptable to the migrant population and feasible for real-time data collection.

Key messages

The process identified potential barriers to the acceptability and feasibility of an app-based study for real-time data collection in the UK migrant population. Organising workshops with migrants allowed for an iterative process of co-production of the HOME app. Their critical comments resulted in subsequent changes to the app design and study methodology.

Validity of UK electronic health records to study migrant health: a population-based cohort study

Background

An estimated 14.3% (9.4 million people) of people living in the UK in 2019 were international migrants. Despite this, little is known about how migrants access and use healthcare services. To use electronic healthcare records (EHRs) to study migration health, a valid migration phenotype is necessary: a transparent reproducible algorithm using clinical terminology codes to determine migration status. We have previously described the validity of a migration phenotype in CALIBER data using the Clinical Practice Research Datalink (CPRD), the largest UK primary care EHR. This study further evaluates the phenotype by examining certainty of migration status.

Methods

This is a population-based cohort study of individuals in CPRD Gold (1997-2018) with a Read term indicating migration to the UK. We describe completeness of recording of migration over time: percentage of individuals recorded as migrants. We also describe cohort size based on certainty of migration status: “definite” (country of birth or visa status terms), “probable” (non-English first/main language terms), and “possible” (non-UK origin terms).

Results

Overall, 2.5% (403,768/16,071,111) of CPRD had ≥1 of 434 terms indicating migration to the UK. The percentage of recorded migrants per year increased from 0.2% (4,417/2,210,551) in 1997 to 3.64% (100,626/2,761,397) in 2018, following a similar trend to national migration data. 44.27% (178,749/403,768) were “definite” migrants and 53.68% (216,731/403,768) were “probable” migrants. Only 2.05%(8,288/16,071,111) were “possible” migrants.

Conclusions

We have created a large cohort of international migrants in the UK and certainty of migration status is high. This cohort can be used to study migration health in UK primary care EHR. The large contribution of language terms make this phenotype particularly suitable for understanding healthcare access and use by non-English speaking migrants who may face additional barriers to care.

Key messages

We have developed a way to study migration health in UK primary care electronic health records. Our method is particularly useful to study healthcare for non-English speaking migrants who may face additional barriers to care.

Left behind: the state of universal health coverage in Europe

Background

Barriers to access healthcare and lack of data undermine Universal Health Coverage (UHC) in Europe, despite the region's clear commitment to the Sustainable Development Goals and UHC. Current indicators measuring unmet healthcare needs in the European Union (EU) often exclude more marginalised groups, further rendering their health needs invisible and the data to inform policy flawed. For effective evaluation of UHC, comprehensive data on the health of these groups is needed.

Methods

We conducted an evaluation of humanitarian healthcare provision of people attending Médecins du Monde (MdM) programmes in seven countries in Europe (Belgium, France, Germany, Luxembourg, Sweden, Switzerland, and the United Kingdom). MdM is a humanitarian organisation, providing care to those excluded from mainstream healthcare services. We describe the characteristics of MdM service users, their determinants of health and healthcare access.

Results

A total of 29,359 people were seen between January 2017 and December 2018. Nearly all were migrants (97.2%, 21,591/22,136), with 66.3% (11,690/17,629) of people reported not having a right or permission to reside in the country they presented in. A majority were living below the poverty line (92.6%, 7,660/8,268), residing in insecure housing (44.3%, 8,895/20,097) or living as street homeless or in emergency shelters (20.4%, 4,107/20,097). Most people reported having no healthcare coverage (81.7%, 14,848/18,164). When asked about barriers to accessing healthcare, 20.8% of responses reported economic barriers (3,960/19,020) and 14.3% reported a lack of knowledge of health system/entitlements (2,718/19,020).

Conclusions

This humanitarian service evaluation highlights the intersecting vulnerabilities and barriers to access healthcare for people excluded from mainstream healthcare systems across Europe. Our findings provide a unique insight into the extent of unmet healthcare needs of migrants and other marginalised populations.

Key messages

UHC requires comprehensive data on the population groups who are many times left without access to health services and who are often excluded from national data collection and research. A majority of MdM service users do not have healthcare coverage and experience multiple and intersecting barriers to access healthcare across Europe.

1 Review of the Identification and Management of Contractures in Inpatients with Dementia In A District General Hospital

Background

Patients with dementia are at risk of contractures which are associated with pain, pressure sores, increased carer burden and reduced function (1). It has been estimated up to 55% of residents in nursing homes have a contracture (2). Locally, patients are identified and treated in care homes. We questioned why comparatively few hospital inpatients were seen.

Methods

We audited acute elderly inpatients at a large district general hospital on two days. Patients with a diagnosis of dementia were identified and then checked for contractures. Information was collected on a proforma. Patients audited on day one were excluded from day two.

Results

410 patients were audited. 100 patients were identified with dementia. 21 individual contractures were identified with the hands been the most common site (47.6%). Only three contractures had been highlighted in the medical notes. Patients with contractures were more likely to be at home with carers or in a care facility (93.7% verse 64.3%). None of the patients with contractures were independently mobile. Higher proportions (31.2% vs 8.3%) with contractures were bedbound compared to those without. Complications were identified, with two patients reporting pain and three patients having pressure sores. Only one patient was receiving treatment for their contractures. Patients with contractures were more likely to have a higher frailty score, had a previous stroke (37.5% verse 13.1%) and have a vascular type dementia (31.3% verse 14.2%).

Conclusions

Contractures were a significant problem in our inpatient population in patients with a diagnosis of dementia. A large proportion were not identified by the clerking team, not receiving treatment and beginning to have complications. Subsequently a presentation highlighting this issue was carried out to junior doctors on the elderly wards, a coding proforma for contractures was produced and a guide to management of this issue is being put together for use in the inpatient setting.

References

1. Souren L, Franssen, Reisberg E. Contractures and loss of function in patients with Alzheimer's disease, J. Am. Geriatr. Soc. 1995; 43(6): 650–655.

2. Offenbacher M, Sauer S, Riess J, Muller M, et al. Disabil Rehabil 2013; 36(7): 529–538.

Dactylitis: A pictorial review of key symptoms

Dactylitis refers to a global swelling of a finger or a toe giving it a clinical sausage-shape presentation. It is an extremely suggestive symptom as it guides the rheumatologist towards a shortlist of diagnoses. However, radiologists are less familiar with dactylitis. The aim of this review is to detail and illustrate the main causes of dactylitis using standard X-ray imaging, ultrasound, computed tomography and magnetic resonance imaging in order to make radiologists more familiar with this symptom by illustrating the various conditions that are associated with dactylitis including infection, peripheral spondyloarthritis, sarcoidosis, microcrystalline deposition, osteoid osteoma, and sickle cell disease.

Implementation of an online chemotherapy checking training module enhances scope of practice and ensures competency

Chemotherapy checking is a complex task and requires a high level of alertness and attention to detail. Learning tools are required to teach the fundamental principles of chemotherapy checking. In conjunction with a graphic design team and with input from Human Factors specialists, an online chemotherapy checking training module was created. A variety of learning methods were incorporated including pre-reading, hands on training, case scenarios, and exam questions. The necessary skills to safely complete chemotherapy checking can be enhanced by the use of this training module.

Genome Sequencing Reveals the Origin of the Allotetraploid Arabidopsis suecica

Polyploidy is an example of instantaneous speciation when it involves the formation of a new cytotype that is incompatible with the parental species. Because new polyploid individuals are likely to be rare, establishment of a new species is unlikely unless polyploids are able to reproduce through self-fertilization (selfing), or asexually. Conversely, selfing (or asexuality) makes it possible for polyploid species to originate from a single individual-a bona fide speciation event. The extent to which this happens is not known. Here, we consider the origin of Arabidopsis suecica, a selfing allopolyploid between Arabidopsis thaliana and Arabidopsis arenosa, which has hitherto been considered to be an example of a unique origin. Based on whole-genome re-sequencing of 15 natural A. suecica accessions, we identify ubiquitous shared polymorphism with the parental species, and hence conclusively reject a unique origin in favor of multiple founding individuals. We further estimate that the species originated after the last glacial maximum in Eastern Europe or central Eurasia (rather than Sweden, as the name might suggest). Finally, annotation of the self-incompatibility loci in A. suecica revealed that both loci carry non-functional alleles. The locus inherited from the selfing A. thaliana is fixed for an ancestral non-functional allele, whereas the locus inherited from the outcrossing A. arenosa is fixed for a novel loss-of-function allele. Furthermore, the allele inherited from A. thaliana is predicted to transcriptionally silence the allele inherited from A. arenosa, suggesting that loss of self-incompatibility may have been instantaneous.

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine: Brussels, Belgium. 15-18 March 2016

[This corrects the article DOI: 10.1186/s13054-016-1208-6.].

Iodine Status over Two Decades: Influence of Seaweed Exposure

Iodine deficiency is known to result in deficits in neuropsychological development in children born to iodine deficient mothers. However, a remedy in terms of iodisation of table salt as is the norm in most countries, has not been embraced by Ireland. The borderline iodine status of the Irish population persists unchanged over the past 20 years with the annual median urinary iodine (UI) varying from 62.9 to 105 μg/L; overall median 72.4 μg/L (WHO recommended 100 μg/L). Exposure to a seaweed rich environment allowing for intake by respiration of seaweed derived gaseous iodine, rather than simple proximity to the sea, confers advantages in terms of iodine intake with 21/46 (45.6%) of schoolchildren in seaweed rich coastal areas having UI values > 150 μg/L compared to 1/28 (3.6 %) and 2/93 (2.2%) in low seaweed abundant coastal and inland areas respectively. The corresponding values for adult females were 31/72 (43%), 7/60 (11.6%) and 21/132 (16.0%). The findings support introduction of iodine prophylaxis through Universal Salt Iodisation (USI), to ensure that women of child bearing age have access to sufficient dietary iodine.

Depressive symptoms and glycated hemoglobin A1c: a reciprocal relationship in a prospective cohort study

BACKGROUND

The aim of this study was to evaluate the dynamic association between depressive symptoms and glycated hemoglobin A1c (HbA1c) levels using data from the English Longitudinal Study of Ageing (ELSA).

METHOD

The sample was comprised of 2886 participants aged ⩾50 years who participated in three clinical assessments over an 8-year period (21% with prediabetes and 7% with diabetes at baseline). Structural equation models were used to address reciprocal associations between depressive symptoms and HbA1c levels and to evaluate the mediating effects of lifestyle-related behaviors and cardiometabolic factors.

RESULTS

We found a reciprocal association between depressive symptoms and HbA1c levels: depressive symptoms at one assessment point predicted HbA1c levels at the next assessment point (standardized β = 0.052) which in turn predicted depressive symptoms at the following assessment point (standardized β = 0.051). Mediation analysis suggested that both lifestyle-related behaviors and cardiometabolic factors might mediate the association between depressive symptoms and HbA1c levels: depressive symptoms at baseline predicted lifestyle-related behaviors and cardiometabolic factors at the next assessment, which in turn predicted HbA1c levels 4 years later. A similar association was observed for the other direction: HbA1c levels at baseline predicted lifestyle-related behaviors and cardiometabolic factors at the next assessment, which in turn predicted depressive symptoms 4 years later.

CONCLUSIONS

Our results suggest a dynamic relationship between depressive symptoms and HbA1c which might be mediated by both lifestyle and cardiometabolic factors. This has important implications for investigating the pathways which could link depressive symptoms and increased risk of diabetes.

The criterion-referenced validity of the FITNESSGRAM Trunk-Extension test

AIM

The purpose of this study was to test utility of different fitness field tests to predict self-reported low-back pain (LBP) in youth.

METHODS

A sample of 376 school aged (4th through 10th grade students) first completed a survey instrument designed to assess past events (and degree) of LBP. On subsequent days, participants completed a battery of different muscular fitness tests including the current FITNESSGRAM trunk extension test. Receiver operator characteristic curves (ROC) were used to test the utility of single and combined scores from various tests to predict self-reported LBP.

RESULTS

The results show that the trunk extension test used in FITNESSGRAM has poor utility for predicting self-reported LBP. In girls, the sit-and-reach, the static curl-up test, and a composite score using static and dynamic curl-up scores had the highest Area Under the Curve (AUC=0.80, 0.71, and 0.79, respectively). Sensitivity (Se) values ranged from 75.0-85.7 while Specificity (Sp) ranged from 59.1-81.4. In boys, the dynamic curl-up test alone was the best predictor of LBP in high-school boys (AUC=0.75, Sensitivity=75.0 and Specificity=74.1).

CONCLUSION

The reasonable Sensitivity values from the ROC analyses indicate that individual and aggregate indicators of musculoskeletal fitness can potentially identify girls that had LBP in the past. However, the low values for Specificity indicates that girls with "No LBP" can be misclassified as being at risk for LBP. The current FITNESSGRAM trunk extension test was not able to discriminate between students with and without LBP therefore, the utility of this test for fitness assessment in youth should be revisited.

Regulation of iodide uptake in placental primary cultures

BACKGROUND

Maintenance of adequate iodide supply to the developing fetus is dependent not only on maternal dietary iodine intake but also on placental iodide transport. The objective of this study was to examine the effects of different pregnancy-associated hormones on the uptake of radioiodide by the placenta and to determine if iodide transporter expression is affected by hormone incubation.

METHODS

Primary cultures of placental trophoblast cells were established from placentas obtained at term from pre-labor caesarean sections. They were pre-incubated with 17β-estradiol, prolactin, oxytocin, human chorionic gonadotropin (hCG) and progesterone either singly or in combination over 12 h with (125)I uptake being measured after 6 h. RNA was isolated from placental trophoblasts and real-time RT-PCR performed using sodium iodide symporter (NIS) and pendrin (PDS) probes.

RESULTS

Significant dose response increments in (125)I uptake by trophoblast cells (p < 0.01) were observed following incubation with hCG (60% increase), oxytocin (45% increase) and prolactin (32% increase). Although progesterone (50-200 ng/ml) and 17β-estradiol (1,000-15,000 pg/ml) alone produced no significant differences in uptake, they facilitated increased uptake when combined with prolactin or oxytocin, with a combination of all four hormones producing the greatest increase (82%). Increased (125)I uptake was accompanied by corresponding increments in NIS mRNA (ratio 1.52) compared to untreated control cells. No significantly increased expression levels of PDS were observed.

CONCLUSIONS

Pregnancy-associated hormones, particularly oxytocin and hCG, have a role in promoting placental iodide uptake which may protect the fetus against iodine deficiency.

P1-08-10: Invasive Lobular Breast Cancer – No Increased Risk of Contralateral Disease

Background: Invasive lobular carcinoma (ILC) is the second most common type of breast cancer accounting for up to 14% of invasive breast cancers. Worldwide the incidence of breast cancer is increasing each year. Large population based studies using the Surveillance, Epidemiology, and End results (SEER) data have shown that the incidence of ILC has increased from 1977 to 1995. ILC has historically been thought to be associated with an increased risk of developing contralateral breast cancer and this belief may, in part, be responsible for the increasing trend towards contralateral prophylactic mastectomy.

Methods: All female patients diagnosed with breast cancer during the time period 1998–2003 were identified from two large cancer registries, Northern and Yorkshire Cancer Registry and Information Service (NYCRIS) and West Midlands Cancer Intelligence Unit (WMCIU). All patients diagnosed with either Infiltrating duct(adeno) carcinoma, microinvasive ductal carcinoma, infiltrating ductular carcinoma (all classified as ‘ductal') or lobular (adeno)carcinoma were included. Patients with a mixed type of breast cancer were excluded from the analysis. Follow-up was complete until October 2010. Data were compiled for diagnosed contralateral breast cancer of any histological type.

Results: Of the 32,735 patients with invasive ductal cancer 898 (2.74%) developed a contralateral breast cancer. In comparison 166 (3.1%) of 5397 patients with lobular cancer developed a contralateral breast cancer. The median time to first contralateral event was equivalent for both morphologies (ductal 40 months and lobular 39 months).

Conclusion: This study suggests that there is no increased risk for developing a contralateral breast cancer in patients diagnosed with an invasive lobular breast cancer.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-08-10.

Trends in primary methamphetamine-related admissions to youth residential substance abuse treatment facilities in Canada, 2005-2006 and 2009-2010

OBJECTIVE

During the last decade, methamphetamine use and issues surrounding its toxicity have triggered major concern in the Canadian government, leading to significant changes in drug policy and funding strategies to limit the societal impact of methamphetamine-related harms. This concern appears justified by research which found in 2005-2006 that 21% of all youth admissions to inpatient substance abuse treatment centres in Canada were due primarily to methamphetamine abuse. Given these patterns of treatment use and targeted governmental initiatives, an open question is whether the demand for methamphetamine treatment found in 2005-2006 has decreased. Our study aims to provide follow-up estimates of admissions for 2009-2010, as well as important trend information for these periods.

METHOD

We developed a comprehensive list of all Canadian residential youth substance abuse treatment facilities. The executive director of each facility was asked about the site's annual caseload, and the proportion of cases primarily due to methamphetamine abuse within the past 12 months.

RESULTS

Our survey data for the periods of 2005-2006 and 2009-2010 show marked reductions in admissions. In 2009-2010, we found that about 6% of all admissions were due primarily to methamphetamine abuse, a substantial drop from the 21% reported in our 2005-2006 study.

CONCLUSIONS

Our data show a significant national reduction in methamphetamine-related admissions. Other reports show that methamphetamine-related treatment admissions in the United States and Mexico declined sharply during 2005-2008, reportedly in association with Mexico's methamphetamine precursor chemical controls, raising the possibility that the controls may also be associated with the declines reported here.

Kr-PLIF for scalar imaging in supersonic flows

Experiments were performed to explore the use of two-photon planar laser-induced fluorescence (PLIF) of krypton gas for applications of scalar imaging in supersonic flows. Experiments were performed in an underexpanded jet of krypton, which exhibited a wide range of conditions, from subsonic to hypersonic. Excellent signal-to-noise ratios were obtained, showing the technique is suitable for single-shot imaging. The data were used to infer the distribution of gas density and temperature by correcting the fluorescence signal for quenching effects and using isentropic relations. The centerline variation of the density and temperature from the experiments agree very well with those predicted with an empirical correlation and a CFD simulation (FLUENT). Overall, the high signal levels and quantifiable measurements indicate that Kr-PLIF could be an effective scalar marker for use in supersonic and hypersonic flow applications.

Is placental iodine content related to dietary iodine intake?

OBJECTIVE

Delivery of iodine to the foetus depends not only on maternal dietary iodine intake but also on the presence of a functioning placental transport system. A role for the placenta as an iodine storage organ has been suggested, and this study compares the iodine content of placentas from women giving birth at term in Ireland and Iran, areas with median urinary iodine of 79 and 206 μg/l respectively.

DESIGN

Placental cotyledon iodine was measured using an alkaline ashing technique with Sandell-Kolthoff kinetic colorimetry. Samples were taken from six sites from the centre and periphery of each cotyledon. Placentas (Ireland n = 58; Iran n = 45) were obtained from consecutive euthyroid women delivering at term.

RESULTS

The median placental iodine (μg/g wet weight) was significantly higher in Iranian than in Irish women (187·2 μg/g vs 34·3 μg/g; P < 0·001). The distribution of individual placental iodine values showed that values >50μg/g were found in 71·0% of Iranian and in only 21·0% of Irish samples. In Irish subjects, the relationship of placental iodine to pregnant population urinary iodine (UI) (ng/g:μg/l) was 1:2 (40:79), while in Iranians this ratio is closer to 1:1 (211:206).

CONCLUSIONS

These findings, by demonstrating an apparent ability of the placenta to store iodine in a concentration-dependent manner, suggest a hitherto undetected role for the placenta. Whether placental iodine has a role in protecting the foetus from inadequacies in maternal dietary iodine intake is as yet unknown.

Does iodine gas released from seaweed contribute to dietary iodine intake?

Thyroid hormone levels sufficient for brain development and normal metabolism require a minimal supply of iodine, mainly dietary. Living near the sea may confer advantages for iodine intake. Iodine (I(2)) gas released from seaweeds may, through respiration, supply a significant fraction of daily iodine requirements. Gaseous iodine released over seaweed beds was measured by a new gas chromatography-mass spectrometry (GC-MS)-based method and iodine intake assessed by measuring urinary iodine (UI) excretion. Urine samples were obtained from female schoolchildren living in coastal seaweed rich and low seaweed abundance and inland areas of Ireland. Median I(2) ranged 154-905 pg/L (daytime downwind), with higher values (~1,287 pg/L) on still nights, 1,145-3,132 pg/L (over seaweed). A rough estimate of daily gaseous iodine intake in coastal areas, based upon an arbitrary respiration of 10,000L, ranged from 1 to 20 μg/day. Despite this relatively low potential I(2) intake, UI in populations living near a seaweed hotspot were much higher than in lower abundance seaweed coastal or inland areas (158, 71 and 58 μg/L, respectively). Higher values >150 μg/L were observed in 45.6% of (seaweed rich), 3.6% (lower seaweed), 2.3% (inland)) supporting the hypothesis that iodine intake in coastal regions may be dependent on seaweed abundance rather than proximity to the sea. The findings do not exclude the possibility of a significant role for iodine inhalation in influencing iodine status. Despite lacking iodized salt, coastal communities in seaweed-rich areas can maintain an adequate iodine supply. This observation brings new meaning to the expression "Sea air is good for you!"

Penetrating skull and brain injury due to a dog bite: a cautionary tale for the unwary

We describe a rare case of depressed skull fracture after a dog bite. To our knowledge only three such cases have been reported.

High crystalline quality single crystal chemical vapour deposition diamond

Homoepitaxial chemical vapour deposition (CVD) on high pressure, high temperature (HPHT) synthetic diamond substrates allows the production of diamond material with controlled point defect content. In order to minimize the extended defect content, however, it is necessary to minimize the number of substrate extended defects that reach the initial growth surface and the nucleation of dislocations at the interface between the CVD layer and its substrate. X-ray topography has indicated that when type IIa HPHT synthetic substrates are used, the density of dislocations nucleating at the interface can be less than 400  cm(-2). X-ray topography, photoluminescence imaging and birefringence microscopy of HPHT grown synthetic type IIa diamond clearly show that the extended defect content is growth sector dependent. ⟨111⟩ sectors contain the highest concentration of both stacking faults and dislocations but ⟨100⟩ sectors are relatively free of both. It has been shown that HPHT treatment of such material can significantly reduce the area of stacking faults and cause dislocations to move. This knowledge, coupled with an understanding of how growth sectors develop during HPHT synthesis, has been used to guide selection and processing of substrates suitable for CVD synthesis of material with high crystalline perfection and controlled point defect content.

A comparison of patient-reported outcomes (PROs) in National Cancer Institute-sponsored cancer treatment trials conducted during two time periods: 1999–2003 and 2003–2008

6618

Background: Over the past decade, the U.S. National Cancer Institute (NCI) support for incorporating Patient-Reported Outcomes (PROs) into disease treatment clinical trials has grown considerably, both in the number of trials, as well as the types of research questions being addressed and the measures used to answer the questions. This presentation will compare the breadth of NCI supported Phase III treatment trials in breast, colo-rectal, lung, and prostate cancers that include PRO secondary endpoints activated during two time periods: 1999–2003 and 2003–2008. Both time periods will be compared to identify the number and type of PRO measures; in addition the targeted PRO domain will be examined by cancer site. Methods: For this study, PRO was broadly defined to include any self-report questionnaire that gathered data on the potential impact that disease treatment might have on patient functioning, quality of life, or symptoms. Using the terms, 'protocol title, lead disease, phase III, quality of life, and instrument name,’ a search was conducted of the NCI database containing breast, colo-rectal, lung, and prostate Phase III treatment trials activated during the two time periods. If a scale was used more than once or if different versions of the scale were used, i.e., FACT-G and FACT-BR, it was only counted once. Results: Between 1999 and 2003, 42 phase III trials in the four major cancers were activated, with 15 trials having one or more PROs as secondary endpoints. Between 2003 and 2008, 50 phase III trials in the four major cancers were activated, with 28 trials having one or more PROs as secondary endpoints. Although the data reveal a 20% increase in the number of phase III trials in the 4 diseases between the two time periods, the number of trials with PRO endpoints has doubled. Conclusions: This significant increase in the use of PROs in phase III trials gives investigators additional data to fully analyze the impact of new treatments. These PRO data will provide researchers, clinicians, and future patients with a more in-depth understanding of the potential for new cancer therapies and technologies to extend both the quantity and quality of life.

No significant financial relationships to disclose.

Evaluation of diabetes determinants in woolly monkeys (Lagothrix lagotricha)

Woolly monkeys (Lagothrix lagotricha) are a threatened specie in the wild with limited successful management in captivity due to diagnosed hypertension and suspected diabetic conditions. Six woolly monkeys with known hypertension problems were tested to determine if diabetes mellitus and current daily diet are underlying links to health problems for the captive population of this species. Blood and urine were collected and serum was analysed for fructosamine, glucose, glycated haemoglobin, insulin, triacylglycerides, total cholesterol, high-density lipoprotein cholesterol (HDL-Chol) and low-density lipoprotein cholesterol (LDL-Chol) while urine was tested for glucose concentrations. Diet disappearance was determined for 3 days prior to blood collection and nutrient content was calculated using Zoo Diet Analysis computer program. Serum analyses were within normal ranges (fructosamine (139-242 micromol/l), glucose (2.22-4.78 mmol/l), glycated haemoglobin (3.52-4.73%), insulin (6.2-13.0 microU/ml), triacylglycerides (0.38-3.4 mmol/l), total cholesterol (2.5-5.1 mmol/l), HDL-Chol (0.4-1.6 mmol/l) and LDL-Chol (1.8-3.4 mmol/l)). Urine glucose concentrations were below the detection limit. Diets were not limiting in starch and total sugars and were similar in non-starch polysaccharides. Potential dietary deficiencies were noted for vitamin A, vitamin D, calcium, phosphorus and selenium. When compared with the available primate reference ranges, the results do not indicate problems with diabetes mellitus or with glucose metabolism and therefore they are not causes of the diagnosed hypertension. Further research to ascertain the true cause of health related problems and the role of dietary factors is needed.

Short-term changes in maternal and neonatal urinary iodine excretion

Investigation of maternal urinary iodine (UI) excretion in the immediate antenatal and early postpartum periods showed a precipitous fall in median values from 93 microg/L antenatally to 36 microg/L at delivery subsequently rising to 49 microg/L and 63 microg/L at days 3 and 10 postpartum respectively. The fate of ingested iodine not appearing in the maternal urine is unknown but measurement of UI in babies born to nursing mothers suggested transfer from the mother with median neonatal values of 117 and 159 microg/L being recorded at days 3 and 10. While maternal UI seemed to relatively unaffected by breast feeding, median UI from breast feeding babies (148 microg/L) was significantly greater than in those bottle feeding (50 microg/L). This was also reflected by the finding that no breast feeding baby had a UI values < 50 microg/L in comparison to 50% of bottle feeders. The depressed values in mothers and relatively high values in their infants could present a false picture and suggest the need to defer any investigations of iodine status at this time. The findings do however suggest a need for further investigations aimed at determining the fate of iodine ingested perinatally and its possible physiological significance in maintaining thyroid status in the mother and neonate.

Reducing transfer times for coronary angiography in patients with acute coronary syndromes: one solution to a national problem

BACKGROUND

Patients with acute coronary syndrome (ACS) are at high risk of further cardiac events and benefit from early intervention, as reflected by international guidelines recommending early transfer to interventional centres. The current average waiting time of up to 21 days contravenes evidence based early intervention, creates geographical inequity of access, wastes bed days, and is unsatisfactory for patients.

METHODS

A regional transfer unit (RTU) was created to expatriate access of ACS patients referred from other centres to the revascularisation service. By redesigning the care pathway patients arriving on the RTU undergo angiography within 24 hours, and then leave the RTU the following day, allowing other ACS patients to be treated.

RESULTS

During the first six months of the RTU, the mean waiting time from referral to procedure decreased from 20 (SD 15) days (range 0-51) to 8 (SD 3) days (range 0-21) for 365 patients transferred from a district general hospital. Ninety seven per cent of patients underwent angiography within 24 hours, 61% having undergone percutaneous coronary intervention at the same sitting, and 78% were discharged home within 24 hours.

CONCLUSIONS

Delivering standards laid out in the National Service Framework, reducing inequalities of care across the region, and facilitating evidence based strategies of care represents a challenging and complex issue. For high risk patients suffering ACS who need early invasive investigation, a coordinated network wide approach together with the creation of an RTU resulted in a 62% reduction in waiting times for no extra resources. Further improvements can be expected through increased capacity of this verified strategy.

Iodine intake in pregnancy in Ireland — A cause for concern?

BACKGROUND

Adequate dietary iodine intake is necessary to maintain maternal thyroid function at a level permitting normal neuropsychological development of the foetus.

AIMS AND METHODS

To determine dietary iodine status by measuring urinary iodine excretion (UIE), proportional to dietary intake, in Irish mothers during the first trimester of pregnancy.

RESULTS

Median UIE showed seasonal variations, being lower in summer than in winter. The median values in pregnant women were, summer 45microg/l, winter 68microg/l. Equivalent values for controls were 43 and 91microg/l respectively. UIE required to achieve WHO recommended daily iodine intakes would be 120-180microg/l. In the Irish subjects UIE values suggestive of iodine deficiency (<50microg/l) were observed in 55% of pregnant women tested in summer and 23% in winter. Dairy milk iodine, a major dietary iodine source, showed similar variation.

CONCLUSIONS

While there is as yet no available evidence of widespread thyroid hypofunction in the Irish obstetric population, the findings are a cause of concern, which if confirmed by a more comprehensive investigation, may indicate the need for iodine prophylaxis.