Global spread, genetic differentiation and selection of barley spot form of net blotch isolates

Spot form of net blotch, caused by Pyrenophora teres f. maculata, is a significant necrotrophic disease of barley that spread world-wide in the 20th century. Genetic relationships were analysed to determine the diversity, survival and dispersal of a diverse collection of 346 isolates from Australia, Southern Africa, North America, Asia Minor and Europe. The results, based on genome-wide DArTseq data, indicated isolates from Turkey were the most differentiated with regional sub-structuring, together with individuals closely related to geographically distant genotypes. Elsewhere, population subdivision related to country of origin was evident, although low levels of admixturing was found that may represent rare genotypes or migration from unsampled populations. Canadian isolates were the next most diverged and Australian and South African the most closely related. With the exception of Turkish isolates, multiple independent Cyp51A mutation events (which confer insensitivity to demethylation inhibitor fungicides) between countries and within regions was evident, with strong selection for a transposable element insertion at the 3' end of the promoter and counter-selection elsewhere. Individuals from Western Australia shared genomic regions and Cyp51A haplotypes with South African isolates, suggesting a recent common origin.

Impact of the COVID-19 pandemic on employment and inequalities: a systematic review of international evidence and critical appraisal of statistical methods

AIMS

To assess the impact of the COVID-19 pandemic on individual labour market outcomes and how these vary over time and between different groups of individuals.

METHODS

Searches were conducted using Medline, Scopus and EconLit. Grey literature searches used Google Scholar and Econpapers. Study quality was assessed using the risk of bias in non-randomised studies of exposure tool (ROBINS-E), accompanied by a directed acyclic graph (DAG) to identify relevant mediators, moderators and confounders.

RESULTS

A total of 85 studies (77 peer-reviewed articles, 8 working papers) were included. The ROBINS-E showed that the overall risk of bias varied between studies from low (n = 14), moderate (n = 56) to serious (n = 15). Studies also varied in terms of outcome measures, study designs and the academic disciplines of researchers. Generally, studies using data collected before and during the pandemic showed large negative effects on employment, working hours and income. Studies that assessed moderators (e.g. by industry, occupation, age, gender, race and country of birth) indicated the pandemic has likely worsened pre-existing disparities in health and work. Generally, women, less educated, non-whites and young workers were affected the most, perhaps due to their jobs involving high levels of personal contact (e.g. hospitality, sales and entertainment) and being less amenable to remote working. The DAG highlighted methodological challenges in drawing robust inferences about COVID-19's impact on employment, including the lack of an unexposed control group.

CONCLUSIONS

The COVID-19 health crisis caused unanticipated and unprecedented changes to employment opportunities around the world, with potential long-term health consequences. Further research should investigate the longer-term impact of COVID-19, with greater attention given to low- and middle-income countries. Our study provides guidance on the design and critical appraisal of future studies.

Generation and Characterization of Mirikizumab, a Humanized Monoclonal Antibody Targeting the p19 Subunit of IL-23

Interleukin (IL)-23 exists as a heterodimer consisting of p19 and p40 and is a key cytokine for promoting inflammatory responses in a variety of target organs. IL-23 plays a key role in the differentiation and maintenance of T helper 17 cells, and deregulation of IL-23 can result in autoimmune pathologies of the skin, lungs, and gut. This study describes the generation and characterization of mirikizumab (miri), a humanized IgG4 monoclonal antibody directed against the p19 subunit of IL-23. Miri binds human and cynomolgus monkey IL-23 with high affinity and binds rabbit IL-23 weakly but does not bind to rodent IL-23 or the other IL-23 family members IL-12, IL-27, or IL-35. Miri effectively inhibits the interaction of IL-23 with its receptor, and potently blocks IL-23-induced IL-17 production in cell-based assays while preserving the function of IL-12. In both local and systemic in vivo mouse models, miri blocked IL-23-induced keratin mRNA or IL-17 production, respectively. These data provide a comprehensive preclinical characterization of miri, for which efficacy and safety have been demonstrated in human clinical trials for psoriasis, ulcerative colitis, and Crohn's disease. SIGNIFICANCE STATEMENT: This article describes the generation and characterization of mirikizumab, a high affinity, neutralizing IgG4 variant monoclonal antibody that is under development for the treatment of ulcerative colitis and Crohn's disease. Neutralization of interleukin (IL)-23 is achieved by preventing the binding of IL-23 p19 subunit to the IL-23 receptor and does not affect the IL-12 pathway.

Pegloticase in Uncontrolled Gout: The Infusion Nurse Perspective

Infused biologics, such as pegloticase, are a core component of managing uncontrolled gout, which is increasing in prevalence. Pegloticase is often the last line of therapy for patients with uncontrolled gout; therefore, achieving a successful course of treatment is critical. The infusion nurse's role in patient education, serum uric acid monitoring, and patient medication compliance is essential for ensuring patient safety and maximizing the number of patients who benefit from a full treatment course of pegloticase. Infusion nurses are on the front lines with patients and need to be educated on potential negative effects associated with the medications they infuse, such as infusion reactions, as well as risk management methods like patient screening and monitoring. Further, patient education provided by the infusion nurse plays a large role in empowering the patient to become their own advocate during pegloticase treatment. This educational overview includes a model patient case for pegloticase monotherapy, as well as one for pegloticase with immunomodulation and a step-by-step checklist for infusion nurses to refer to throughout the pegloticase infusion process. A video abstract is available for this article at http://links.lww.com/JIN/A105.

'Nesting networks': Women's experiences of social network support in high-risk pregnancy

OBJECTIVE

Social support, an individual's social relationships (both online and offline), may provide protection against adverse mental health outcomes, such as anxiety and depression, which are high in women who have been hospitalised with high-risk pregnancy. This study explored the social support available to women at higher risk of preeclampsia during pregnancy by examining personal social networks.

DESIGN

Semi-structured interviews were accompanied by social network mapping using the web-based social networking tool GENIE.

SETTING

England.

PARTICIPANTS

Twenty-one women were recruited, of whom 18 were interviewed both during pregnancy and postnatally between April 2019 and April 2020. Nineteen women completed maps pre-natally, 17 women completed maps pre-natally and post-natally. Women were taking part in the BUMP study, a randomised clinical trial that included 2441 pregnant individuals at higher risk of preeclampsia and recruited at a mean of 20 weeks' gestation from 15 hospital maternity units in England between November 2018 and October 2019.

RESULTS

Women's social networks tightened during pregnancy. The inner network changed most dramatically postnatally with women reporting fewer network members. Interviews revealed networks were primarily 'real-life' rather than online social networks, with members providing emotional, informational, and practical support. Women with a high-risk pregnancy valued the relationships they developed with health professionals during pregnancy, and would like their midwife to have a more central role in their networks by providing informational and, where needed, emotional support. The social network mapping data supported the qualitative accounts of changing networks across high-risk pregnancy.

CONCLUSION

Women with a high-risk pregnancy seek to build "nesting networks" to support them through pregnancy into motherhood. Different types of support are sought from trusted sources. Midwives can play a key role.

PRACTICE IMPLICATIONS

As well as highlighting other potential needs during pregnancy and the ways in which they can be met, support from midwives has a key role. Through talking to women early in their pregnancy, signposting information and explaining ways to contact health professionals regarding informational or emotional support would fill a gap that currently is met by other aspects of their network.

Interleukin 36 receptor-inducible matrix metalloproteinase 13 mediates intestinal fibrosis

Background

Fibrostenotic disease is a common complication in Crohn's disease (CD) patients hallmarked by transmural extracellular matrix (ECM) accumulation in the intestinal wall. The prevention and medical therapy of fibrostenotic CD is an unmet high clinical need. Although targeting IL36R signaling is a promising therapy option, downstream mediators of IL36 during inflammation and fibrosis have been incompletely understood. Candidate molecules include matrix metalloproteinases which mediate ECM turnover and are thereby potential targets for anti-fibrotic treatment. Here, we have focused on understanding the role of MMP13 during intestinal fibrosis.

Methods

We performed bulk RNA sequencing of paired colon biopsies taken from non-stenotic and stenotic areas of patients with CD. Corresponding tissue samples from healthy controls and CD patients with stenosis were used for immunofluorescent (IF) staining. MMP13 gene expression was analyzed in cDNA of intestinal biopsies from healthy controls and in subpopulations of patients with CD in the IBDome cohort. In addition, gene regulation on RNA and protein level was studied in colon tissue and primary intestinal fibroblasts from mice upon IL36R activation or blockade. Finally, in vivo studies were performed with MMP13 deficient mice and littermate controls in an experimental model of intestinal fibrosis. Ex vivo tissue analysis included Masson's Trichrome and Sirius Red staining as well as evaluation of immune cells, fibroblasts and collagen VI by IF analysis.

Results

Bulk RNA sequencing revealed high upregulation of MMP13 in colon biopsies from stenotic areas, as compared to non-stenotic regions of patients with CD. IF analysis confirmed higher levels of MMP13 in stenotic tissue sections of CD patients and demonstrated αSMA+ and Pdpn+ fibroblasts as a major source. Mechanistic experiments demonstrated that MMP13 expression was regulated by IL36R signaling. Finally, MMP13 deficient mice, as compared to littermate controls, developed less fibrosis in the chronic DSS model and showed reduced numbers of αSMA+ fibroblasts. These findings are consistent with a model suggesting a molecular axis involving IL36R activation in gut resident fibroblasts and MMP13 expression during the pathogenesis of intestinal fibrosis.

Conclusion

Targeting IL36R-inducible MMP13 could evolve as a promising approach to interfere with the development and progression of intestinal fibrosis.

Mosaic results after preimplantation genetic testing for aneuploidy may be accompanied by changes in global gene expression

Aneuploidy in preimplantation embryos is a major cause of human reproductive failure. Unlike uniformly aneuploid embryos, embryos diagnosed as diploid-aneuploid mosaics after preimplantation genetic testing for aneuploidy (PGT-A) can develop into healthy infants. However, the reason why these embryos achieve full reproductive competence needs further research. Current RNA sequencing techniques allow for the investigation of the human preimplantation transcriptome, providing new insights into the molecular mechanisms of embryo development. In this prospective study, using euploid embryo gene expression as a control, we compared the transcriptome profiles of inner cell mass and trophectoderm samples from blastocysts with different levels of chromosomal mosaicism. A total of 25 samples were analyzed from 14 blastocysts with previous PGT-A diagnosis, including five low-level mosaic embryos and four high-level mosaic embryos. Global gene expression profiles visualized in cluster heatmaps were correlated with the original PGT-A diagnosis. In addition, gene expression distance based on the number of differentially expressed genes increased with the mosaic level, compared to euploid controls. Pathways involving apoptosis, mitosis, protein degradation, metabolism, and mitochondrial energy production were among the most deregulated within mosaic embryos. Retrospective analysis of the duration of blastomere cell cycles in mosaic embryos revealed several mitotic delays compared to euploid controls, providing additional evidence of the mosaic status. Overall, these findings suggest that embryos with mosaic results are not simply a misdiagnosis by-product, but may also have a genuine molecular identity that is compatible with their reproductive potential.

167 ASSISTED DECISION-MAKING (CAPACITY) ACT 2015: KNOWLEDGE AND ATTITUDES AMONG HOSPITAL DOCTORS

Background

Assessing capacity is part of our daily practice, and an important pillar of patient centred care. Assisted Decision-Making (Capacity) Act 2015, which is due to commence in June 2022, is an act to provide reform of the law to assist patients who require help in making decisions in a manner that will ensure their autonomy, dignity, and best interests. This study aimed to investigate the knowledge, attitudes, and confidence of hospital doctors regarding this act.

Methods

This study was conducted using an anonymous online survey completed by hospital doctors from all levels and specialties in a tertiary hospital. The survey contained two sections, the first asked questions on confidence and attitudes about capacity assessment. The second section contained practical scenarios to test knowledge around the new framework for decision support under the Act.

Results

Of the 670 consultants and non-consultant hospital doctors (NCHD) surveyed, an 11% response rate was achieved (75 respondents), 44% were consultants 56% were NCHD. 43% reported to lack confidence in assessing capacity. 92% felt that they needed more training regarding the act. Also, 80% agreed the act will have an impact on our practice. 80% thought capacity was carried out by a certain specialty (mostly Psychiatry and Geriatrics). In the decision support scenarios 18-27% of responders felt they did not know what the appropriate level of decision support was. In each scenario, with the exception of one, the most frequent response was the correct one but responses were widely distributed on most questions.

Conclusion

Despite the lack of a representative sample, doctors’ knowledge about capacity seems to have improved compared to previously carried out studies. However, our study appears to indicate a significant knowledge gap and further training is needed regarding the Assisted Decision-Making (Capacity) Act 2015 proposed to commence next month. Mandatory training on the act should be considered by HSE and the professional training bodies.

The impact of inhaler technique on clinical outcomes in adolescents and adults with asthma: A systematic review

BACKGROUND

Many patients with asthma use their inhalers incorrectly, which can lead to sub-optimal asthma control and an increased risk of exacerbations. The Accuhaler/Diskus and Turbuhaler are arguably two of the most commonly used dry powder inhalers worldwide.

METHODS

A systematic literature review (SLR) was conducted to assess the impact of inhalation errors with these dry powder inhalers on clinical outcomes in asthma. Database searches were conducted in MEDLINE, Embase and proceedings from scientific conferences. Observational studies in adults and adolescents with asthma, reporting data for Accuhaler/Diskus and Turbuhaler devices and at least one outcome of interest, were included. Dual-independent screening and validation of studies was performed.

RESULTS

The search identified 35 studies. A range of inhaler errors was observed across studies and devices. In 8 out of the 9 studies that involved the two devices, the percentage of overall inhaler error rates was numerically (7 studies) or significantly (1 study) higher for Turbuhaler than Diskus, ranging from 3.7% to 71.9% for Diskus and 1.2%-83% for Turbuhaler. Critical errors, reported in three studies using similar definitions, ranged from 20% to 43% for Diskus and 32%-100% for Turbuhaler. Five studies reported a significant association between inhaler errors and worse asthma control, while one showed no difference.

CONCLUSIONS

This SLR identified a large range of inhaler errors with both devices. Across devices, a better inhalation technique was associated with better asthma outcomes. This systematic review confirms the importance of patients using their inhalers correctly as an integral part of achieving optimal asthma outcomes.

Oral, intranasal, and intravenous abuse potential of serdexmethylphenidate, a novel prodrug of d-methylphenidate

OBJECTIVES

Serdexmethylphenidate (SDX) chloride (Cl) is a novel prodrug of d-methylphenidate (d-MPH). These studies evaluated the abuse potential of SDX Cl when administered orally, intranasally (IN), and intravenously (IV).

METHODS

Three randomized, double-blind, placebo- and active-controlled crossover studies were conducted in recreational drug users to evaluate the abuse-related effects of oral SDX (120 and 240 mg) vs. extended-release (ER) d-MPH (80 mg) and phentermine (60 mg); IN SDX (80 mg) vs. d-MPH (40 mg), and IV SDX (30 mg) vs. d-MPH (15 mg). Abuse-related subjective measures, pharmacokinetics, and safety were assessed.

RESULTS

The primary endpoint of maximum (E_max) Drug Liking (DL) (0-100-point scale) was significantly higher following d-MPH vs. placebo, validating the studies. In the oral study, DL E_max was significantly higher following 80 mg ER d-MPH (E_max = 81.5) than 120 mg SDX (E_max = 62.8, p < .001) and 240 mg SDX (E_max = 63.8, p = .006); and following 60 mg phentermine (E_max = 80.2) than 120 mg SDX (p = .0195), but not 240 mg SDX (p = .0665). DL E_max scores were significantly higher following IN d-MPH vs SDX (E_max = 93.2 vs. 71.0, p < .0001) and following IV d-MPH vs. SDX (E_max = 84.3 vs. 56.6, p = .001). Intravenous SDX was non-inferior to placebo (p = .001) for DL E_max. Secondary endpoints (e.g. Take Drug Again) were generally consistent with the primary endpoint. Maximal and overall d-MPH exposure was lower for SDX than d-MPH for all routes. Adverse events typical of stimulants were more frequent with d-MPH than SDX.

CONCLUSIONS

These findings indicate that the novel d-MPH prodrug, SDX, has lower abuse potential than d-MPH and support its classification as a C-IV controlled substance.

P-082 Microfluidic-based device selects sperm with less DNA damage and higher motility, what else?

Study question

Does the microfluidic-based sperm selection device ZyMōt improve sperm parameters and other laboratory key performance indicator (KPI) values compared to the conventional swim-up method?

Summary answer

The microfluidic-based sperm selection device ZyMōt selects sperm with lower DNA fragmentation and higher motility than conventional swim-up method in intracytoplasmic sperm injection (ICSI) cycles.

What is known already

Elevated levels of sperm DNA fragmentation (SDF) in semen samples have been associated with poor embryo development and low pregnancy rates. SDF refers to breaks in the sperm's genetic material, mainly due to defects during spermatogenesis and other factors such as reactive oxygen species that are favored by centrifugation. Conventional sperm selection methods, by integrating centrifugation into their protocols, have become ineffective in selecting sperm with low SDF. In order to solve this problem and improve reproductive outcomes, microfluidic-based devices such as ZyMōt have been designed to avoid centrifugation and select spermatozoa with low SDF.

Study design, size, duration

Prospective, experimental, single-center study conducted from June to December 2021. A total of 14 couples with ≥ 10 retrieved oocytes were recruited for an intra-patient comparison. Semen sample was split and processed for ICSI by the conventional swim-up method or by the microfluidic-based device ZyMōt. Each fraction was used to fertilize half of the total number of oocytes retrieved. SDF index, semen parameters, useful blastocyst rate, fertilization rate and morphokinetic variables were observed.

Participants/materials, setting, methods

Oocytes retrieved were from own (n = 96) and donation cycles (n = 93). From each patient, the cohort of oocytes was divided into two groups: 1) inseminated with spermatozoa selected by swim-up and 2) inseminated with spermatozoa selected by ZyMōt 850 µL device. Embryo evaluation and development were then followed by time-lapse monitoring using EmbryoScope. Sperm chromatin dispersion (SCD) assay was used to measure SDF, analyzed by ImageJ. Each treatment followed routine protocol established in the clinical practice.

Main results and the role of chance

SDF index was significantly lower in ZyMōt group in comparison with swim-up group (10% vs 20%), indicating a better selection by the ZyMōt of sperm with less DNA breaks. Additionally, ZyMōt group also presented a significantly greater number of spermatozoa with progressive motility (96.9% vs 95.4%). In contrast, useful blastocyst rate showed a slightly, but not significantly, increment in ZyMōt group compared to swim-up group (53.2% vs 46.6%). No significant differences in fertilization rate or sperm recovery rate were observed between groups. Regarding morphokinetic parameters, timing variables from first cell division to blastocyst stage (t2-tB) showed no significant correlation with ZyMōt group contrasted with swim-up. Blastocysts were evaluated and a value was assigned with respect to their quality (A to D). There was a higher number of embryos with A grade in ZyMōt group and a higher number of embryos with D grade in swim-up group. The annotated variables were assessed using paired t-test and P value &lt;0.05 was considered statistically significant.

Limitations, reasons for caution

The impact on reproductive outcomes may vary depending on whether the breakage is single- or double-stranded, however, SCD is not able to distinguish between them. These, together with the oocyte's ability to repair sperm damage, lead us to the explanation for the non-significance on embryo quality.

Wider implications of the findings

This study provides further insights into the use of ZyMōt for the selection of low SDF spermatozoa in a simple manner. Its use could be indicated in patients with a high SDF value in their semen samples. Benefits on reproductive outcome will be confirmed with larger sample size.

Trial registration number

2102-VLC-007-MD

O-145 Limitations of designing carrier screening panels based on estimated frequencies. Concordance between recommendations and observed frequencies

Study question

Are recommended carrier screening (CS) panels suitable worldwide or should they be designed taking into account observed carrier frequencies (CF)?

Summary answer

Limitations of carrier screening panel recommendations based on estimated frequencies could be avoided with a worldwide-database of observed carrier frequencies.

What is known already

Currently, there is no consensus for specific gene panel for CS, but some scientific societies, based on estimated carrier frequencies, recommend to analyze a narrow panel rather than exome. The American College of Medical Genetics and Genomics (ACMG) recently recommended a 4-tiered system, encouraging to analyze genes in tier 3, genes with less carrier frequency (tier 4) are only recommended to be analyzed on specific cases. Similarly, Sociedad Española de Fertilidad (SEF) recommends in absence of genetic matching (GM) a 6 gene basic panel for donor screening and in a GM context suggests a 50-diseases panel.

Study design, size, duration

This study includes 8542 patients analyzed with an expanded carrier screening panel of 300 genes, including autosomal recessive (AR) and X-linked (XL) disorders by next-generation sequencing (NGS). ACMG guidelines were followed for variant interpretation and only pathogenic and likely pathogenic variants were reported. The study has been conducted between August 2018 and December 2021.

Participants/materials, setting, methods

DNA was extracted and sequenced. Obtained data was processed by bioinformatic tools. CF for diseases analyzed was stablished. Genes were categorized according to tier-3 of the ACMG recommendations (112 genes, only 80 included on this study) and also by 50-disease panel of SEF recommendations (49 genes, 40 included on this study). Likewise, analyzed diseases were divided in two groups according to the obtained CF: A (CF ≤ 1/200 - 56 genes); B (CF &gt; 1/200 - 244 genes).

Main results and the role of chance

The analysis of the 8542 patients showed that 2582 (30.23%) of them were not carriers of any disease analyzed, 2205 (25.81%) of them were only carriers of one or more of the diseases included in the ACMG tier3 panel and 3755 (43.96%) were carriers of at least one disease not included this category. 

When diseases analyzed were categorized by SEF 50-disease panel, 2280 (26.69%) patients were only carriers of one or more of the diseases included in this panel and 3680 (43.08%) were carriers of at least one disease that would not be analyzed by this panel.  

On the other hand, when diseases were divided by observed carrier frequency, a total of 3476 patients (40.69%) were carriers only of a disease(s) included in A group. With this panel, only 2484 (29.08%) of the 8542 patients would not have been correctly diagnosed. Moreover, the variants undetected would affect less frequent diseases (B group).

It is important to notice that group A has been created regarding the data of a 300 gene panel. If another panel would have been analyzed, the group of genes may have changed, but the data collected highlights the importance of observed CF on panel design.

Limitations, reasons for caution

Not all Tier3 ACMG and 50-disease SEF genes are included due to original panel limitations. Observed CF may vary depending on the population analyzed. NGS panel design does not cover variants in regulatory or deep intronic regions. Pseudogenes can interfere. Not all structural variants can be detected by NGS.

Wider implications of the findings

These data highlight the importance of reviewing the genes included in carrier screening panels by their frequency. Furthermore, it points out the need to have updated databases with observed CF available so an universal panel can be designed or adapted to patient’s needs.

Trial registration number

Not applicable

Mother and father depression symptoms and child emotional difficulties: a network model

Introduction

Enhancing understanding of depression symptom interactions between parents and associations with subsequent child emotional difficulties will inform targeted treatment of depression to prevent transmission within families.

Objectives

To use a network approach to identify ‘bridge’ symptoms that reinforce mother and father depression, and whether bridge symptoms, as well as other symptoms, impact subsequent child emotional difficulties.

Methods

Symptoms were examined using two unregularized partial correlation network models. The study included 4,492 mother-father-child trios from a prospective, population-based cohort in the United Kingdom. Mother and father reports of depression symptoms were assessed when the child was twenty-one months old. Child emotional difficulties were reported by the mother at ages nine, eleven and thirteen years.

Results

Bridge symptoms mutually reinforcing mother and father depression symptoms were feelings of guilt and self-harm ideation, whereas anhedonia acted as a bridge from the father to the mother, but not vice-versa (fig.1, network 1). The symptom of feelings of guilt in mothers was the only bridge symptom which directly associated with child emotional difficulties. Other symptoms that directly associated with child emotional difficulties were feeling overwhelmed for fathers and anhedonia, sadness, and panic in mothers (fig.1, network 2).

Conclusions

Specific symptom interactions are central to the co-occurrence of depression symptoms between parents. Of interest, only one of the bridge symptoms associated with later child emotional difficulties. In addition, specific symptom-to-child outcomes were identified, suggesting that different symptoms in mothers and fathers are central for increased vulnerability in children.

Disclosure

No significant relationships.

Nature-Based Early Childhood Education and Children's Physical Activity, Sedentary Behavior, Motor Competence, and Other Physical Health Outcomes: A Mixed-Methods Systematic Review

BACKGROUND

The purpose was to synthesize evidence on the association between nature-based Early Childhood Education (ECE) and children's physical activity (PA) and motor competence (MC).

METHODS

A literature search of 9 databases was concluded in August 2020. Studies were eligible if (1) children were aged 2-7 years old and attending ECE, (2) ECE settings integrated nature, and (3) assessed physical outcomes. Two reviewers independently screened full-text articles and assessed study quality. Synthesis was conducted using effect direction (quantitative), thematic analysis (qualitative), and combined using a results-based convergent synthesis.

RESULTS

1370 full-text articles were screened and 39 (31 quantitative and 8 qualitative) studies were eligible; 20 quantitative studies assessed PA and 6 assessed MC. Findings indicated inconsistent associations between nature-based ECE and increased moderate to vigorous PA, and improved speed/agility and object control skills. There were positive associations between nature-based ECE and reduced sedentary time and improved balance. From the qualitative analysis, nature-based ECE affords higher intensity PA and risky play, which could improve some MC domains. The quality of 28/31 studies was weak.

CONCLUSIONS

More controlled experimental designs that describe the dose and quality of nature are needed to better inform the effectiveness of nature-based ECE on PA and MC.

Fetoscopic Laser Ablation for Twin-to-Twin Transfusion Syndrome: A 15-year Review of Perinatal Survival

Objective Twin to twin transfusion syndrome (TTTS) complicates 5-15% of monochorionic twin pregnancies and untreated is associated with a 90% mortality rate. The aim was to present the perinatal survival of patients with TTTS treated with laser ablation, by a national fetal medicine team. Methods This was a review of all cases of TTTS treated with fetoscopic laser ablation performed from March 2006 through to December 2020. All patients treated with fetoscopic laser were identified from the hospital database. The perinatal outcomes for the overall cohort and the individual Quintero stages were determined. Results A total of 155 cases of TTTS underwent fetoscopic laser ablation during the study period. The median gestational age at diagnosis was 19+1 weeks, with a mean growth discordance of 23.6%. The Quintero stage at diagnosis was: Stage 1 6.5% (10/155), Stage 2 49% (76/155), Stage 3 38.7% (60/155), Stage 4 5.8% (9/155). There was at least one survivor in 83.2% (129/155) of pregnancies, with dual survival in 52.9% (82/155). An increase in the rate of any survivor was observed from 75% (2006-2014) to 94% (2014-2020) (p<0.05). Dual survival decreased with increasing Quintero Stage (p<0.05). 80.6% (125/155) of pregnancies delivered prior to 34+6 weeks gestation. Conclusion Fetoscopic laser ablation is the recommended first line treatment for severe TTTS. We observed a survival rate of at least one twin in 83.2% pregnancies which is comparable to internationally published data on single-centre outcomes.

A taxonomy of occupational and organisational stressors and protectors of mental health reported by veterinary professionals in Australasia

AIM

To develop a taxonomy of positive and negative occupational and organisational factors reported that impact the mental health of veterinary professionals.

METHODS

Veterinary professionals working in Australasia were surveyed between February and June of 2021. The survey comprised two questions related to participants' perceptions of the positive and negative aspects of their job role that impact their mental health and wellbeing. Reflexive thematic analysis was employed to analyse the responses and generate two taxonomies of occupational and organisation stressors and protectors reported by participants.

RESULTS

Fifty-three responses from veterinary professionals were analysed. The final stressor taxonomy generated contained 9 overarching themes and 36 subthemes. The most common of these were negative work conditions, challenging relationships with clients, and adverse events and patient outcomes. The taxonomy of protectors contained 11 overarching themes and 32 subthemes, with the most common including fulfillment and satisfaction, positive work conditions, and relationships with colleagues.

CONCLUSION

This study is the first to examine both positive and negative factors in the veterinary industry reported by veterinary professionals in Australasia. The results highlighted stressors that can be addressed on both an individual and organisational level to promote the mental and health well-being of professionals working in the animal care industry.

HCV cure: an appropriate moment to reduce cannabis use in people living with HIV? (ANRS CO13 HEPAVIH data)

BACKGROUND

Thanks to direct-acting antivirals, hepatitis C virus (HCV) infection can be cured, with similar rates in HCV-infected and HIV-HCV co-infected patients. HCV cure is likely to foster behavioral changes in psychoactive substance use, which is highly prevalent in people living with HIV (PLWH). Cannabis is one substance that is very commonly used by PLWH, sometimes for therapeutic purposes. We aimed to identify correlates of cannabis use reduction following HCV cure in HIV-HCV co-infected cannabis users and to characterize persons who reduced their use.

METHODS

We used data collected on HCV-cured cannabis users in a cross-sectional survey nested in the ANRS CO13 HEPAVIH cohort of HIV-HCV co-infected patients, to perform logistic regression, with post-HCV cure cannabis reduction as the outcome, and socio-behavioral characteristics as potential correlates. We also characterized the study sample by comparing post-cure substance use behaviors between those who reduced their cannabis use and those who did not.

RESULTS

Among 140 HIV-infected cannabis users, 50 and 5 had reduced and increased their use, respectively, while 85 had not changed their use since HCV cure. Cannabis use reduction was significantly associated with tobacco use reduction, a decrease in fatigue level, paying more attention to one's dietary habits since HCV cure, and pre-HCV cure alcohol abstinence (p = 0.063 for alcohol use reduction).

CONCLUSIONS

Among PLWH using cannabis, post-HCV cure cannabis reduction was associated with tobacco use reduction, improved well-being, and adoption of healthy behaviors. The management of addictive behaviors should therefore be encouraged during HCV treatment.

744 3 YEAR FOLLOW-UP OF SEDATIVE PRESCRIBING FOR RESPONSIVE BEHAVIOURS IN NURSING HOME RESIDENTS, AN IRISH STUDY

Introduction

Sedative medications are commonly prescribed for older adults; these include neuroleptics, benzodiazepines, opioids, ‘z’ drugs and trazadone. The prevalence of sedative drug prescriptions is increasing (1). Nursing home residents are three times more likely to be prescribed benzodiazepines (2). Regular medication review and education have been shown to reduce rates of sedative use in nursing homes (3). We previously demonstrated a significant reduction in prescription of these target medications at an Irish nursing home with specific focus, within scheduled medication reviews, on reduction or discontinuation of the target drugs in combination with education on management of Behavioural and Psychological symptoms (BPSD). This audit examines the prescribing patterns 3 years on from the initial audit.

Methods

Point prevalence study of sedative prescriptions and BPSD of all 95 nursing home residents on 6/5/21. Comparison with data from two previous audits in the same unit. All data was anonymised. Data analysed with SPSS statistical software.

Results

Sustained significant drop in quetiapine use from 30% of residents to 14% post-intervention in 2018 and three-year follow-up (p = 0.06). Borderline significant reduction in overall neuroleptics (from 39% to 25%, p = 0.06). Significant rise in ‘z’ drug prescription (from 8% to 17%, p = 0.03). BPSD reported in 33%, compared to 49% pre-intervention.

Conclusion

Regularly scheduled medication reviews can effectively rationalise sedative prescription rates in nursing home residents. Increasing ‘z’ drug prescription likely represents the appropriate replacement of neuroleptics. Reduced BPSD may be due to reporting bias of staff since regular education has been introduced or changing cohort of residents. References numbered above not included given limited word count.

A121 QUANTIFYING INTER-OBSERVER VARIABILITY IN THE SEGMENTATION OF RECTAL TUMORS IN ENDOSCOPY IMAGES AND ITS EFFECTS ON DEEP LEARNING

Background

Tumor delineation in endoscopy images is a crucial part of clinical diagnoses and treatment planning for rectal cancer patients. However, it is challenging to detect and adequately determine the size of tumors in these images, especially for inexperienced clinicians. This motivates the need for a standardized, automated segmentation method. While deep learning has proven to be a powerful tool for medical image segmentation, it requires a large quantity of high-quality annotated training data. Since the annotation of endoscopy images is prone to high inter-observer variability, creating a robust unbiased deep learning model for this task is challenging.

Aims

To quantify the inter-observer variability in the manual segmentation of tumors in endoscopy images of rectal cancer patients and investigate an automated approach using deep learning.

Methods

Three gastrointestinal physicians and radiation oncologists (G1, G2, and G3) segmented 2833 endoscopy images into tumor and non-tumor regions. The whole image classifications and the pixelwise classifications into tumor and non-tumor were compared to quantify the inter-observer variability. Each manual annotator is from a different institution.

Three different deep learning architectures (FCN32, U-Net, and SegNet) were trained on the binary contours created by G2. This naive approach investigates the effectiveness of neglecting any information about the uncertainty associated with the task of tumor delineation.

Finally, segmentations from G2 and the deep learning models’ predictions were compared against ground truth labels from G1 and G3, and accuracy, sensitivity, specificity, precision, and F1 scores were computed for images where both segmentations contained tumors.

Results

The deep-learning segmentation took less than 1 second, while manual segmentation took approximately 10 seconds per image. There was significant inter-observer variability for the whole-image classifications made by the manual annotators (Figure 1A). The segmentation scores achieved by the deep learning models (SegNet F1:0.80±0.08) were comparable to the inter-observer variability for the pixel-wise image classification (Figure 1B).

Conclusions

The large inter-observer variability observed in this study indicates a need for an automated segmentation tool for tumors in endoscopy images of rectal cancer patients. While deep learning models trained on a single observer’s labels can segment tumors with an accuracy similar to the inter-observer variability, these models do not accurately reflect the intrinsic uncertainty associated with tumor delineation. In our ongoing studies, we investigate training a model with all observers’ contours to reflect the uncertainty associated with the tumor segmentations.

Funding Agencies

CIHRNSERC

COVID-19 reinfection after pregnancy

Background

There have been reports of COVID-19 reinfections, but the immunological characterization of these cases is partial. We report a case of reinfection with SARS-CoV-2, where the first infection occurred in the course of late pregnancy.

Case presentation

On May 27, 2020, a 37-year-old woman gave birth at full term, 3 hours after full dilatation. She developed fever (38.3 °C) after delivery. Mild biological anomalies compatible with COVID-19 were observed: lymphopenia, thrombocytopenia, elevated D-Dimers, CRP, and LDH. At 6-month follow-up, she reported having contracted COVID-19 with high fever, rhinorrhea, hand frostbites, cough, headache, dysgeusia and anosmia.

Conclusions

We report a case of COVID-19 reinfection with a first mild infection during late pregnancy and a more aggressive second infection 5 months later.

Low dose thioguanine guided by therapeutic drug monitoring is a safe and effective alternative in inflammatory bowel disease patients intolerant to conventional thiopurines

BACKGROUND AND AIMS

Thioguanine is an alternative thiopurine for IBD patients. We evaluated the short-term efficacy and safety of low dose therapeutic drug monitored (TDM) thioguanine.

METHODS

A retrospective evaluation of IBD patients intolerant to conventional thiopurines started on thioguanine from 2017-2019 with dosing guided by TDM was conducted. Clinical response was defined for Ulcerative colitis (UC) as a reduction of partial MAYO score ≥ 3 with reduction in rectal bleeding score of at least 1 and a final rectal bleeding sub score of 0-1 at week 12 of therapy. Crohn's disease (CD) response was defined as a reduction of Harvey-Bradshaw index ≥ 3 (HBI) at week 12 of therapy. Remission was defined in UC as partial MAYO score of < 2 and in CD as HBI score of < 5.

RESULTS

46 patients were included in the study. The median thioguanine dose was 20 mg/day (SD 7.3, range: 10-40 mg/day) with a median 6-TGN level of 564 pmol/8×108 (IQR 517) for CD and 672 pmol/8×108 (IQR 349) for UC. The overall clinical response rate was 62% (13/21), intention to treat (ITT). Maintenance of remission was 76% (19/25, ITT). 37% (17/46) of patients experienced an adverse effect. No early cases of NRH were seen.

CONCLUSION

Thioguanine was tolerated well in 63% of patients. Clinical response was seen in 62 % of and maintenance of remission was high at 76 %. No cases of early NRH were seen. Longer-term follow-up is required to ensure safety and to assess durability of response. This article is protected by copyright. All rights reserved.

98 SCHEDULED MEDICATION REVIEWS AND EDUCATION ON SEDATIVE PRESCRIBING FOR RESPONSIVE BEHAVIOURS IN NURSING HOME RESIDENTS, A 3 YEAR FOLLOW-UP STUDY

Background

Sedative medications including neuroleptics, benzodiazepines, opioids, ‘z’ drugs and trazadone are commonly prescribed for older adults. Nursing home residents are three times more likely to be prescribed benzodiazepines. Sedative medications are associated with significant risks including falls and delirium in older adults. Neuroleptics also increase risk of cerebrovascular disease and functional decline. Regular medication review and education have been shown to reduce rates of sedative use in nursing homes. Scheduled medication reviews were introduced in an Irish nursing home with a specific focus on reduction or discontinuation of these target medications in combination with education of management of Behavioural and Psychological symptoms (BPSD). We demonstrated previously a significant reduction in prescribing following these interventions. This audit examines the prescribing patterns 3 years on from the initial audit.

Methods

Point prevalence study of sedative prescriptions and BPSD on 6/5/21 of all 95 nursing home residents. Data compared with two preceding audits in 2018 in the same unit. All data anonymised. Data analysed with SPSS statistical software.

Results

Significant reduction in quetiapine use sustained from 30% of residents pre-intervention to 14% post-intervention in 2018 and 2021 (p = 0.06).

Neuroleptic prescription reduced from 39% to 25% (p = 0.06).

‘Z’ drug prescribing increased from 8% to 17% (p = 0.03).

33% of residents had BPSD reported compared to 49% pre-intervention.

Conclusion

3 year follow-up showed regularly scheduled medication reviews and education in a nursing home can effectively rationalise sedative prescription rates. Sustained reduction in neuroleptics and increased ‘z’ drug prescriptions may represent appropriate replacement. Reduced BPSD may be due to changing nursing home resident cohort or reporting bias of staff since the introduction of regular education.

Novel cryoballoon to isolate pulmonary veins in patients with paroxysmal atrial fibrillation: one-year outcomes in a multicenter study

Background

Recently, a novel cryoballoon (CB; POLARx) has been developed with increased steerability which maintains size and pressure throughout the ablation. Initial clinical data has demonstrated acute procedural safety and efficacy in de novo pulmonary vein isolation (PVI) procedures in patients with paroxysmal atrial fibrillation (AF). However, there are limited studies demonstrating the long-term efficacy of the CB.

Purpose

To evaluate the long-term safety and efficacy of the novel CB in treating paroxysmal AF.

Methods

This was a non-randomized, prospective, multi-center study. Fifty-eight consecutive patients with paroxysmal AF were enrolled at 4 centers for de novo PVI procedures. Cryoablation was delivered for 180s if time to isolation was ≤60s. Otherwise a 240s cryoablation was performed. PVI was confirmed with entrance and exit block testing. Patients were followed for 1 year with 24-hour Holter monitoring at 3, 6, and 12 months. After a 3-month blanking period, recurrence was defined as having any documented, symptomatic episode(s) of AF or atrial tachycardia.

Results

Acute isolation with the CB was achieved in 230 of 231 pulmonary veins (99.6%) with 5.2±1.5 cryoapplications per patient (1.3±0.6 cryoapplications per vein). There were 4 patients (6.9%) with phrenic nerve injury (3 resolved during the index procedure; 1 resolved at 6 months follow-up). One serious adverse device event was reported: femoral arterial embolism event occurring 2 weeks post index procedure (1.7%). Of the 56 patients that had complete 12-month follow-up, 43 (76.8%) were free from recurrent atrial arrhythmias.

Conclusion

Initial multicenter clinical experience with the novel CB has demonstrated long-term safety and efficacy of PVI in patients with paroxysmal AF. Further studies are underway to confirm these findings.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Boston Scientific

Transcriptome-wide Gene Expression Analysis in Peri-implantitis Reveals Candidate Cellular Pathways

OBJECTIVE

Peri-implantitis is a condition resulting in destructive inflammation in the peri-implant soft tissue barrier. Clinically, it demonstrates vast clinical differences to periodontitis that suggest distinct inflammatory mechanisms. Implant-derived titanium particles (i-TiPs) frequently found around diseased implants appear to alter the microenvironment and confer resistance to antibiotic treatments. Studies in orthopedic implants have demonstrated potent inflammatory responses to i-TiPs involving a variety of cell types in aseptic conditions. Nonetheless, the genetic programs of cells surveilling and supporting the peri-implant soft tissue barrier in response to the combined challenges of biomaterial degradation products and oral bacteria are poorly defined. Thus, we studied gene expression specific to oral peri-implant inflammatory disease.

METHODS

Peri-implant tissues were collected from healthy or diseased implants (N = 10) according to the 2018 classification criteria. Following RNA extraction and purification, a gene-level view of the transcriptome was obtained via a next-generation transcriptome-wide microarray profiling workflow (Clariom S; Applied Biosystems) that covers >20,000 well-annotated genes. A discovery analysis assessed global differential expression of genes and identified pathways in peri-implant health versus disease.

RESULTS

Genes involved in the endosomal-lysosomal pathway, such as actin polymerization, were strongly upregulated in diseased tissues (P < .05), proposing increased intracellular activities in response to bacteria and i-TiPs. Cellular respiration pathways involved in oxidative stress were highly transcribed in all peri-implant samples, suggesting that implant-specific factors may trigger a constant state of oxidative stress.

CONCLUSION

Within the limitations of this discovery study, expressive upregulation of genes in the endosomal-lysosomal and oxidative stress pathway suggests that inflammation related to receptor-driven responses to extracellular signals, such as i-TiPs and pathogens, may have a crucial role in peri-implantitis. Results warrant external replication in validation cohorts.

KNOWLEDGE TRANSFER STATEMENT

Our findings regarding physiologic processes affected by peri-implantitis could advance knowledge of the mechanisms and consequences of the disease. Understanding the cellular programs that partake in peri-implant inflammation has the potential to translate to novel treatment strategies for patients with peri-implantitis.

A combined DGT - DET approach for an in situ investigation of uranium resupply from large soil profiles in a wetland impacted by former mining activities

An in situ methodology combining DET and DGT probes was applied in a wetland soil, downstream of a former uranium mine (Rophin), to evaluate metal resupply by calculating the R ratio (R = [U]_DGT/[U]_{pore water}) from a high resolution and large (75 cm) soil profile. Our study confirms its applicability in soil layers with varying properties; only soil layers with low water content or coarse texture appear to be limiting factors. For soil profiles, DET provides new insights of the distribution of Uranium as soluble species (free ions, small inorganic complexes, …) along the pore water profile, whereas DGT highlights the presence of other "DGT labile" species. The pairing of DET and DGT, plus the calculation of the R, highlights two U behaviors in combining results from red-ox sensitive elements (Mn, Fe). First, in the organic topsoil layer, an increase in [U]_DET and [U]_DGT at 3-4 cm reflects the desorption of U probably trapped onto Fe- and Mn-oxohydroxides in a DGT-labile form. However, the resupply from soil to pore water is close to a diffusion only case (R < 0.2) meaning that a portion of U is certainly tightly bound by OM in soil as non-labile species. Second, a peak in [U]_DGT perfectly corresponding to the former mine deposit layer signifies the presence of U under DGT-labile species. Moreover, a maximum R value of 0.87 demonstrates the near complete resupply of U from a labile fraction in this layer, as opposed to other elements like Pb.

Triangle Singularity as the Origin of the a_{1}(1420)

The COMPASS Collaboration experiment recently discovered a new isovector resonancelike signal with axial-vector quantum numbers, the a_{1}(1420), decaying to f_{0}(980)π. With a mass too close to and a width smaller than the axial-vector ground state a_{1}(1260), it was immediately interpreted as a new light exotic meson, similar to the X, Y, Z states in the hidden-charm sector. We show that a resonancelike signal fully matching the experimental data is produced by the decay of the a_{1}(1260) resonance into K^{*}(→Kπ)K[over ¯] and subsequent rescattering through a triangle singularity into the coupled f_{0}(980)π channel. The amplitude for this process is calculated using a new approach based on dispersion relations. The triangle-singularity model is fitted to the partial-wave data of the COMPASS experiment. Despite having fewer parameters, this fit shows a slightly better quality than the one using a resonance hypothesis and thus eliminates the need for an additional resonance in order to describe the data. We thereby demonstrate for the first time in the light-meson sector that a resonancelike structure in the experimental data can be described by rescattering through a triangle singularity, providing evidence for a genuine three-body effect.

P–505 The right age to tell? The insufficiency of the age criteria for characterizing the experience of French donor conceived families in disclosing to their offspring

Study question

Is age a key criteria for characterizing the experience of families in telling donor offspring about the facts of their conception?

Summary answer

The study shows that, although donor offspring’s age at the time of disclosure has an impact, it is insufficient to describe these families’ experiences

What is known already

Secrecy was the norm for decades in donor conception, but “openness” has now become the new core value for institutions, professionals and interest groups. Accordingly, in recent years information-sharing practices have shifted in donor conceived families, but a proportion of parents, especially heterosexual couples, still appear to not inform their children about their being donor conceived. Disclosure recommendations seem difficult to apply in practice. A recurring question is: when should children be told? Age is presented as a key criteria: the younger the children are when their conception story is shared, the less of a problem it would create.

Study design, size, duration

The qualitative social science study includes two sets of semi-directive interviews conducted with 20 French sperm donor conceived adults (April-Dec. 2019) and 22 French parents by sperm, egg or double donation (Feb.-Oct. 2020). Calls for interviews aimed at donor conceived adults and parents by donation were shared on the Internet, in the media (press, radio, television) and through interest groups (PMAnonyme, BAMP!, MAIA) in France. The contact initiative was left to potential participants.

Participants/materials, setting, methods

Donor conceived participants include 17 women and 3 men conceived 1960–2000 through anonymous sperm donation in heteroparental families.

The parent participants include 20 families (20 mothers, 2 fathers) who used donor conception—mainly anonymous (19)—in France, Spain and the Czech Republic starting in the 1980s. 17 conceived as heteroparental couples, 2 as solo-mothers-by-choice and 1 as a same-sex couple. 17 have already informed their offspring of the facts of their conception.

Main results and the role of chance

The participants’ experiences of disclosure appear to be bound to their historical and social context, especially regarding the prevailing norms on secrecy. Older parents mention having been advised by clinic professionals to keep the facts of their conception from their child(ren). Some also feared the stigma related to infertility. In contrast, some younger donor conceived participants recall the use of a children’s book while being told of their conception as toddlers. Beyond age, the larger context thus affects information-sharing practices.

Furthermore, experiences of disclosure are impacted by the family context and history. Some are embedded within larger events such as divorces or the death of a family member. The story of the donation may be linked to narratives of diseases (such as cancer) or traumatic events (such as the loss of a fetus in utero) that may prevail over donor conception or make it untellable.

Age proves to be an insufficient criteria to qualify these experiences, all the more so since “disclosure” sometimes unfolds in several steps. Some parents have first talked about their fertility issues without mentioning the use of a donor. Behind the prevailing norm of “openness”, difficulties in actually disclosing are confirmed.

Limitations, reasons for caution

Being qualitative, the study only includes a small number of participants without claiming exhaustivity nor representativity. It imperfectly reports on the view of those who do not disclose, as all participants question the principle of secrecy, many being members of interest groups defending openness.

Wider implications of the findings: Our results complement existing studies that emphasize the weight of age in donor conceived families’ experience regarding disclosure. Age alone cannot describe information-sharing practices that are embedded within their historical and social context as well as the family context and history. Results thus inform familial difficulties related to disclosure.

Trial registration number

Not applicable

P–549 What trophectoderm cells from mosaic embryos tell us about embryonic competence at the transcriptional level

Study question

Does transcriptome of remaining trophectoderm (TE) reflect the developmental potential of mosaic blastocysts after preimplantation genetic testing for aneuploidy (PGT-A)? Summary answer: TE from low-degree mosaic (Low-mos) and high-degree mosaic (High-mos) blastocysts are transcriptionally equivalent, standing between euploid and aneuploid categories and displaying key deregulated developmental processes.

What is known already

Blastocysts classified as mosaic by PGT-A are associated with lower implantation and higher miscarriage rates than those classified as euploid, yet they still lead to healthy babies. Unveiling the true developmental identity of these embryos faces a dilemma: understanding to which extent they represent technical artefacts or whether they hold own potential to implant and give rise to normal pregnancies. Current RNA sequencing (RNA-seq) techniques allow for the determination of whole transcriptomic profiles even from single cells, which paves the way for the identification of new molecular keys of embryonic competence.

Study design, size, duration

Prospective study comparing RNA-seq data of remaining TE from blastocysts classified as euploid (n = 4), Low-mos (n = 5), High-mos (n = 4) and aneuploid (n = 6) by PGT-A. Participants were recruited between October 2018 and November 2019 at IVI-RMA Valencia.

Participants/materials, setting, methods

Chromosomal mosaicism was defined in the range 30%-&lt;50% (Low-mos) and 50%-&lt;70% (High-mos) using a next-generation sequencing (NGS) validated algorithm. Whole TE fractions were separately collected and processed for RNA-seq. Differentially expressed genes (DEGs) were calculated with DESeq2 package [Benjamini-Hochberg (BH)-adjusted p &lt; 0.01 & abs(log2FoldChange)&gt;2 significant]. Fgsea algorithm was used for enrichment analysis on Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and Gene Ontology (GO) terms (BH-adjusted p &lt; 0.01 significant).

Main results and the role of chance

For comparisons, TE from euploid blastocysts were used as control. At the gene level, 15 DEGs were found in Low-mos, 20 DEGs in High-mos, and 64 DEGs in aneuploid blastocysts. To address the functional implications of these differences, pathways significantly deregulated according to KEGG and GO categories were identified. TE from aneuploid blastocysts displayed significant downregulation in up to 115 KEGG and GO processes directly involved in processing and integrity maintenance of nuclear and mitochondrial genomes, a reflection of their aberrant chromosomal identity. In addition, TE from High-mos and Low-mos were transcriptionally equivalent (0 DEGs between both groups), with 23 overlapping KEGG and GO processes significantly downregulated compared with control. Importantly, main significantly-affected processes included mitotic sister chromatid segregation, NIK NF-kB activity, regulation of apoptosis, and pathways related to the biosynthesis and metabolism of proteins, fatty acids, carbohydrates and steroid hormones. These findings indicate that mosaic embryos comprise a unique developmental entity, which swims between the euploid and aneuploid waterfronts and may regulate survival by diverse mechanisms, including cell proliferation and apoptosis.

Limitations, reasons for caution

This is a descriptive, single-center study with limited sample size. TE fractions were obtained by micromanipulation, which may have led to potential cross-contamination with the inner cell mass.

Wider implications of the findings: Transcriptomic equivalence between Low-mos and High-mos TE fractions questions the biological significance of inferring mosaicism degrees from single biopsies. Deregulated processes in these embryos support their reduced developmental and live birth potential, pointing to mechanisms that may mediate survival in the presence of aneuploid cells, as shown in the mouse.

Trial registration number

Not applicable