What importance do donors and recipients attribute to the nuclear DNA-related genetic heritage of oocyte donation?

STUDY QUESTION

How do oocyte donors and recipients perceive the genetic link related to the transfer of nuclear DNA between donors and offspring?

SUMMARY ANSWER

Whether they are donors or recipients, individuals attach great importance to the transmission of their genetic heritage, since 94.5% would opt for the pronuclear transfer method to preserve this genetic link in the context of oocyte donation.

WHAT IS KNOWN ALREADY

Since 1983, the use of oocyte donation has increased worldwide. Performed in France since the late 1980s and initially offered to women with premature ovarian insufficiency, its indications have progressively expanded and now it is proposed in many indications to prevent the transmission of genetically inherited diseases. This has resulted in an increase in the waiting time for access to oocyte donation due to the difficulty in recruiting oocyte donors in French ART centres. Several articles have discussed how to fairly distribute donor oocytes to couples, but few have interviewed women in the general population to record their feelings about oocyte donation, as either the donor or recipient and the importance given to the genetic link between the oocyte donors and the children born. Mitochondrial replacement therapy (MRT) is a technique originally developed for women at risk of transmitting a mitochondrial DNA mutation. Recently, MRT has been considered for embryo arrest and oocyte rejuvenation as it could help females to reproduce with their own genetic material through the transfer of their oocyte nucleus into a healthy donor oocyte cytoplasm.

STUDY DESIGN, SIZE, DURATION

We conducted an opinion survey from January 2021 to December 2021, during which 1956 women completed the questionnaire. Thirteen participants were excluded from the analysis due to incomplete responses to all the questions. Consequently, 1943 women were included in the study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We specifically developed a questionnaire for this study, which was created and distributed using the Drag'n Survey® software. The questionnaire consisted of 21 items presented alongside a video created with whiteboard animation software. The aim was to analyse whether certain factors, such as age, education level, marital status, number of children, use of ART for pregnancy, video viewing, and knowledge about oocyte donation, were associated with feelings towards oocyte donation, by using a univariate conditional logistic regression model. This statistical method was also used to assess whether women would be more inclined to consider oocyte donation with the pronuclear transfer technique rather than the whole oocyte donation. All parameters found to be statistically significant in the univariate analysis were subsequently tested in a multivariate model using logistic regression.

MAIN RESULTS AND THE ROLE OF CHANCE

Most women were concerned about the biological genetic contribution of the donated oocyte (94.8%). The most common reason for a women's reluctance to donate their oocytes was their unwillingness to pass on their genetic material (33.3%). Nearly 70% of women who were initially hesitant to donate their oocytes indicated that they would reconsider their decision if the oocyte donation was conducted using donated cytoplasm and the pronuclear transfer technique. Concomitantly, >75% of the respondents mentioned that it would be easier to receive a cytoplasm donation. The largest proportion of the population surveyed (94.5%) expressed their support for its legalization.

LIMITATIONS, REASONS FOR CAUTION

In this study, a substantial portion of the responses came from individuals with medical or paramedical backgrounds, potentially introducing a recruitment bias among potential donors. The rate of missing responses to the question regarding the desire to become an oocyte donor was 13.6%, while the question about becoming an oocyte cytoplasm donor had a missing response rate of 23%. These missing responses may introduce a bias in the interpretation of the data.

WIDER IMPLICATIONS OF THE FINDINGS

This study was the first to demonstrate that, for the French population studied, the combination of oocyte cytoplasm donation with pronuclear transfer could offer a promising approach to enhance the acceptance of oocyte donation for both the donor and the recipient.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was used for this study. The authors have no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Determinants of work-family balance satisfaction during the pandemic: Insights from Québec

The first wave of the COVID pandemic was the most challenging for employed parents, and more specifically for women. In Québec, research has shown a deterioration in the psychological health of parents in the early weeks of the pandemic. In this research, we investigate how Québec parents who remained employed during the lockdown in 2020 perceived their work-family balance in the stressful context of new earning and caregiving constraints, drawing on survey data collected in May 2020. Our approach integrates insights from psychological, managerial and sociological literatures. We find that most parents who remained employed found their work-family balance "easy" in the first months of the pandemic, but women felt less satisfied with their work-family balance than men as well as those whose employers were less understanding and supportive, and those whose workloads increased. The implications of these results are discussed in the light of previous studies on work-family intersections, to show that gender continues to matter when family members are faced with extraordinary circumstances such as the closing of childcare and schools, even in the egalitarian context of Québec, where fathers are perceived as legitimate caregivers.

Sulfate groups position determines the ionic selectivity and syneresis properties of carrageenan systems

The salt sensitivity and selectivity feature of α-carrageenan (α-Car) were investigated and compared with κ-carrageenan (κ-Car) and iota-carrageenan (ι-Car). These carrageenans are identified by one sulfate group on the 3,6-anhydro-D-galactose (DA) for α-Car, D-galactose (G) for κ-Car and on both carrabiose moieties (G and DA) for ι-Car. The viscosity and temperature, where order-disorder transition have been observed, were greater in presence of CaCl₂ for α-Car and ι-Car compared with KCl and NaCl. Conversely, the reactivity of κ-Car systems were greater in presence of KCl than CaCl₂. Unlike κ-Car systems, the gelation of α-Car in presence of KCl was observed without syneresis. Thus, the position of sulfate group on the carrabiose determines the importance of counterion valency too. The α-Car could be a good alternative to κ-Car to reduce the syneresis effects.

POS0587 TRAJECTORIES AND FACTORS INFLUENCING THE EVOLUTION OF HAND GRIP AMONG PATIENTS WITH RHEUMATOID ARTHRITIS

Background

Rheumatoid arthritis (RA) is characterized by an early reduced grip strength which persists over time despite the remission of the disease suggesting the presence of a sarcopenia.

Objectives

To study the evolution of the grip strength measured by the handgrip. by identifying different trajectories and associated factors.

Methods

Patients with active RA who visited the Rheumatology Department of Clermont-Ferrand University Hospital for initiating bDMARD were invited to participate to the longitudinal cohort RCVRIC analyzing cardiovascular risk and chronic inflammatory rheumatic disease. Within the RCVRIC cohort 175 RA initially underwent a handgrip determination. 143 patients had at least 2 handgrip measurements over 2 years, allowing analysis of trajectories by the “Group Based Trajectory Modeling” method. For the trajectories, handgrip was expressed in terms of percentage of the theoretical value defined according to age and sex. The clinical characteristics of the disease, the therapeutic response, and the body composition associated with each trajectory were analyzed.

Results

At inclusion, the handgrip was normal among only 4% of patients, with an alteration of 51% of its theoretical value. After 2 years of follow-up, a majority of patients improved their handgrip trajectory to reach an average of 68% of the theoretical one, but only 15.7% of the patients normalized their handgrip. Four trajectories have been identified along with associated factors:

1st trajectory consists of low handgrip with little improvement and was composed of: 9 patients (6.3%), median age 60 years [53.6;69.3], 88% women, disease duration 17.99 years [6.78;24.9], DAS 28 ESR 4.68 ± 1.29, and initial handgrip 21% of the theoretical value [8;24].

2nd trajectory shows good improvement (+72%) and was composed of: 70 patients (49%), median age 58.9 years [54.4;64.3], 84% women, disease duration 5.99 years [1.46;14.8], DAS 28 ESR 4.43 ± 1.07, and initial handgrip 32% of the theoretical value [17.8;46.4].

3rd trajectory shows moderate improvement (+25%) and was composed of: 43 patients (30%), median aged 60.7 years [45.7;69.4], 79% women, disease duration 3.5 years [1.25;9.9], DAS 28 ESR 4.0 ± 1.03 and initial handgrip 60% of the theoretical value [48.2;76].

4th trajectory shows high handgrip and was composed of: 21 patients (14.7%), 57% women, median age 57.9 years old [49.7; 67.4], disease duration 3.81 years [2.14; 10.7], DAS 28 ESR 3.68 ±1.29 and initial hand grip 92% of the theoretical value [85; 100].

Significant differences at inclusion between the 4 trajectories were observed. The 4th trajectory was characterized by a higher proportion of men (p=0.05), lower disease activity (DAS 28 ESR (p=0.02), SDAI (p=0.04)), better initial handgrip (p=0.03) and 6 min walk test (p=0.0001), and a lower percentage of fat mass (p=0.04). In contrast, a higher disability (HAQ, p=0.002), a lower total lean body mass (p=0.001) and poorer therapeutic response (p=0.04) were noted in trajectories 1 and 2.

Conclusion

After 2 years of follow-up, a majority of patients improved their handgrip trajectory. However, very few patients normalized their hand grip. Four trajectories of handgrip were identified; the main indicators of hand grip’s improvement were the control of the disease activity, low functional disability, walking performance, a low percentage of fat mass and high lean mass.

References

[1]Cruz-Jentoft AJ, and al. Sarcopenia: revised European consensus on definition and diagnosis. Age Ageing. janv 2019

[2]An HJ, and al. Sarcopenia in Autoimmune and Rheumatic Diseases: A Comprehensive Review. Int J Mol Sci. 7 août 2020

[3]Shiratori AP and al. Evaluation protocols of hand grip strength in individuals with rheumatoid arthritis: systematic review. Rev Bras Reumatol. avr 2014

[4]Dodds RM, et al. Grip strength across the life course: normative data from twelve British studies. PloS One. 2014;

Acknowledgements

I thank the department of rheumatology of Clermont Ferrand.

Disclosure of Interests

None declared.

Implication of folate deficiency in CYP2U1 loss of function

Hereditary spastic paraplegias are heterogeneous neurodegenerative disorders. Understanding of their pathogenic mechanisms remains sparse, and therapeutic options are lacking. We characterized a mouse model lacking the Cyp2u1 gene, loss of which is known to be involved in a complex form of these diseases in humans. We showed that this model partially recapitulated the clinical and biochemical phenotypes of patients. Using electron microscopy, lipidomic, and proteomic studies, we identified vitamin B2 as a substrate of the CYP2U1 enzyme, as well as coenzyme Q, neopterin, and IFN-α levels as putative biomarkers in mice and fluids obtained from the largest series of CYP2U1-mutated patients reported so far. We also confirmed brain calcifications as a potential biomarker in patients. Our results suggest that CYP2U1 deficiency disrupts mitochondrial function and impacts proper neurodevelopment, which could be prevented by folate supplementation in our mouse model, followed by a neurodegenerative process altering multiple neuronal and extraneuronal tissues.

POS0365 ANTI-TNF GLUCOCORTICOID RECEPTOR MODULATOR ANTIBODY DRUG CONJUGATE FOR THE TREATMENT OF AUTOIMMUNE DISEASES

Background:

Glucocorticoids (GC) are potent drugs used for treating many inflammatory diseases. While GCs are effective in many immune diseases, dose and duration of administration is limited due to significant side effects. Resting immune cells have very little TNF expression on the cell surface and it is only in an activated state that TNF expression is upregulated. Upon immune cell stimulation, TNF is upregulated and although a significant amount of TNF is cleaved from an activated cell, a portion remains on the cell surface. We have observed that anti-TNF antibodies bind to transmembrane TNF (tmTNF) and undergo endocytosis to the lysosome (1). We have developed a stable antibody drug conjugate (ADC), ABBV-3373, that has a proprietary, highly potent, glucocorticoid receptor modulator (GRM) payload linked to an anti-TNF monoclonal antibody (mAb) that is able to deliver the GC payload to activated immune cells.

Objectives:

We hypothesized that a TNF ADC with a GRM payload would be able to deliver increased efficacy through both TNF inhibition and targeted GRM payload delivery to activated immune cells while sparing systemic glucocorticoid side effects.

Methods:

A mouse surrogate TNF GRM ADC was characterized in an acute in vivo contact hypersensitivity model of inflammation (CHS) and in a mouse model of collagen induced arthritis (mCIA). Additionally, the human anti-TNF GRM ADC, ABBV-3373 has been characterized in healthy volunteers.

Results:

In the CHS model the anti-TNF GRM ADC significantly inhibited the inflammatory response with minimal effect on systemic GC biomarkers. In mCIA a single dose of an anti-TNF GRM ADC, administered at disease onset, was able to completely inhibit arthritis for greater than 30 days while an anti-TNF mAb only partially inhibited disease. ABBV-3373, a human anti-TNF GRM ADC with a GC payload, was evaluated in a Phase 1 study in healthy volunteers. ABBV-3373 demonstrated antibody-like PK profile and ABBV-3373 did not impact cortisol levels at predicted efficacious doses while control subjects that received a single oral dose of 10 mg prednisone demonstrated expected decreases in cortisol levels.

Conclusion:

These data suggest that an anti-TNF ADC delivering a GRM payload into activated immune cells may provide improved efficacy in immune mediated diseases, while minimizing systemic side effects associated with standard GC treatment.

References:

[1]Deora, A. et al. MABs. 2017;9(4):680-695.

Disclosure of Interests:

Bob Stoffel Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Michael McPherson Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Axel Hernandez Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Christian Goess Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Suzanne Mathieu Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Wendy Waegell Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Shaughn Bryant Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Adrian Hobson Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Melanie Ruzek Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Yinuo Pang Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Hartmut Kupper Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Ronilda D’Cunha Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Julie Parmentier Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie, Timothy Radstake Shareholder of: AbbVie, Grant/research support from: AbbVie, Employee of: AbbVie

CSNK2B: A broad spectrum of neurodevelopmental disability and epilepsy severity

CSNK2B has recently been implicated as a disease gene for neurodevelopmental disability (NDD) and epilepsy. Information about developmental outcomes has been limited by the young age and short follow-up for many of the previously reported cases, and further delineation of the spectrum of associated phenotypes is needed. We present 25 new patients with variants in CSNK2B and refine the associated NDD and epilepsy phenotypes. CSNK2B variants were identified by research or clinical exome sequencing, and investigators from different centers were connected via GeneMatcher. Most individuals had developmental delay and generalized epilepsy with onset in the first 2 years. However, we found a broad spectrum of phenotypic severity, ranging from early normal development with pharmacoresponsive seizures to profound intellectual disability with intractable epilepsy and recurrent refractory status epilepticus. These findings suggest that CSNK2B should be considered in the diagnostic evaluation of patients with a broad range of NDD with treatable or intractable seizures.

Cannabis use assessment and its impact on pain in rheumatologic diseases: a systematic review and meta-analysis

OBJECTIVES

Despite classic analgesic or effective treatments in rheumatic diseases, such as synthetic DMARDs in RA, patients remain in pain and often turn to non-prescribed pharmacological alternatives, such as cannabis self-therapeutic use. However, this medical use of cannabis has not been thoroughly studied.

METHODS

We performed a systematic literature review up to June 2020. The incidence of cannabis consumption was calculated by metaproportion. Differences between cannabis users and non-users were expressed as standardized mean differences using the inverse-variance method. We also assessed the effects of cannabis on pain.

RESULTS

A total of 2900 patients reported cannabis consumption in a sample of 10 873 patients [incidence 40.4% (95% confidence interval (CI): 0.28, 0.54)], and 15.3% (95% CI: 0.07, 0.27) specified that they were currently taking cannabis. Cannabis use was higher in the four fibromyalgia studies [68.2% (95% CI: 0.41, 0.90), n = 611] compared with seven articles concerning RA or lupus [26.0% (95% CI: 0.14, 0.41), n = 8168]. Cannabis consumption was associated with a decrease in pain intensity [VAS pain at baseline 8.2 (2.9) vs 5.6 (3.5) mm over time; pooled effect size -1.75 (95% CI: -2.75, -0.76)]. Cannabis users were younger [58.4 (11.4) vs 63.6 (12.1) years; P <0.001], more often smokers [OR 2.91 (95% CI: 1.84, 4.60)] or unemployed [OR 2.40 (95% CI: 1.31, 4.40)], and had higher pain intensity [5.0 (2.4) vs 4.1(2.6) mm; P <0.001] than non-users.

CONCLUSION

Nearly 20% of patients suffering from rheumatologic diseases actively consume cannabis, with an improvement in pain. The issue of cannabis use in the management of these patients should be addressed during medical consultation, essentially with cannabis-based standardized pharmaceutical products.

Rare deleterious mutations of HNRNP genes result in shared neurodevelopmental disorders

BACKGROUND

With the increasing number of genomic sequencing studies, hundreds of genes have been implicated in neurodevelopmental disorders (NDDs). The rate of gene discovery far outpaces our understanding of genotype-phenotype correlations, with clinical characterization remaining a bottleneck for understanding NDDs. Most disease-associated Mendelian genes are members of gene families, and we hypothesize that those with related molecular function share clinical presentations.

METHODS

We tested our hypothesis by considering gene families that have multiple members with an enrichment of de novo variants among NDDs, as determined by previous meta-analyses. One of these gene families is the heterogeneous nuclear ribonucleoproteins (hnRNPs), which has 33 members, five of which have been recently identified as NDD genes (HNRNPK, HNRNPU, HNRNPH1, HNRNPH2, and HNRNPR) and two of which have significant enrichment in our previous meta-analysis of probands with NDDs (HNRNPU and SYNCRIP). Utilizing protein homology, mutation analyses, gene expression analyses, and phenotypic characterization, we provide evidence for variation in 12 HNRNP genes as candidates for NDDs. Seven are potentially novel while the remaining genes in the family likely do not significantly contribute to NDD risk.

RESULTS

We report 119 new NDD cases (64 de novo variants) through sequencing and international collaborations and combined with published clinical case reports. We consider 235 cases with gene-disruptive single-nucleotide variants or indels and 15 cases with small copy number variants. Three hnRNP-encoding genes reach nominal or exome-wide significance for de novo variant enrichment, while nine are candidates for pathogenic mutations. Comparison of HNRNP gene expression shows a pattern consistent with a role in cerebral cortical development with enriched expression among radial glial progenitors. Clinical assessment of probands (n = 188-221) expands the phenotypes associated with HNRNP rare variants, and phenotypes associated with variation in the HNRNP genes distinguishes them as a subgroup of NDDs.

CONCLUSIONS

Overall, our novel approach of exploiting gene families in NDDs identifies new HNRNP-related disorders, expands the phenotypes of known HNRNP-related disorders, strongly implicates disruption of the hnRNPs as a whole in NDDs, and supports that NDD subtypes likely have shared molecular pathogenesis. To date, this is the first study to identify novel genetic disorders based on the presence of disorders in related genes. We also perform the first phenotypic analyses focusing on related genes. Finally, we show that radial glial expression of these genes is likely critical during neurodevelopment. This is important for diagnostics, as well as developing strategies to best study these genes for the development of therapeutics.

Pregnancy-induced increased heart rate is independent of thyroid hormones

Background

The heart rate increases by 10–20 beats per minute (bpm) throughout pregnancy in women, reaching maximum heart rate in the third trimester. During pregnancy, important changes in thyroid hormones also occur, with increases of up to 50% in the levels of triiodothyronine (T₃), the biological active thyroid hormone. In addition, T₃ has been shown to regulate cardiac electrophysiology.

Objective

Thus, in the present study the potential contribution of T₃ in pregnancy-induced increased heart rate was explored.

Methods

We compared the heart rate between nonpregnant and pregnant mice under control conditions and after altering thyroid hormone levels with T₃ and propylthiouracil (PTU, an antithyroid drug) treatments.

Results

Consistent with the clinical data, we found a 58% rise in T₃ levels during pregnancy in mice. Although pregnant mice had a higher baseline heart rate (607 ± 8 bpm, P = .004) and higher T₃ levels (1.9 ± 0.4 nM, P = .0005) than nonpregnant mice (heart rate: 546 ± 16 bpm; T₃ levels: 1.2 ± 0.1 nM), their heart rate responded similarly to T₃ treatment as nonpregnant mice (nonpregnant: Δ130 ± 22 bpm; pregnant: Δ126 ± 17 bpm, P = .858). Additionally, the heart rate remained significantly elevated (607 ± 11 bpm, P = .038) and comparable to untreated pregnant mice, after the use of the antithyroid drug PTU, although T₃ levels (1.3 ± 0.2 nM, P = .559) returned to nonpregnant values.

Conclusion

Based on these results, it is unlikely that T₃ contributes significantly to the pregnancy-induced increased heart rate.

Disease-modifying drug retention rate according to patient age in patients with early rheumatoid arthritis: analysis of the ESPOIR cohort

Physicians are sometimes hesitant to use disease-modifying antirheumatic drugs (DMARDs) in elderly patients with rheumatoid arthritis (RA), as they are deemed too fragile, although there are no sufficient scientific evidence. We aimed to compare DMARD treatment retention in early RA patients from the ESPOIR cohort, according to age upon inclusion. Overall, treatment retention was evaluated as the percentage of patients whose DMARDs were not stopped, with stratification by age group: < 50, 50-64, and > 65 years. Survival curves were measured using the Kaplan-Meier method. Of the entire ESPOIR cohort (n = 813), 7% were > 65 years old. Methotrexate (MTX) was used by 521 patients, and was the sole DMARD for 198 patients. MTX treatment retention appeared better in patients > 65 years old compared to < 50 years old [HR 0.45 (0.25; 0.81); p = 0.008, n = 195/198] with adjustment on sex, smoking, positive anti-cyclic citrullinated peptide antibodies, positive rheumatoid factor, body mass index, changes in DAS28 and corticosteroid treatment. The proportion of patients using etanercept (n = 111), and this drug's retention rate, did not differ according to patient age. The proportion of patients treated with adalimumab (n = 104) was significantly higher in patients < 50 years old (p = 0.003), and treatment retention was marginally better among younger patients [HR 1.68 (0.88; 3.22), p = 0.12]. Within the ESPOIR cohort, DMARD retention did not appear to differ according to age-except for better retention of MTX treatment in patients 50-64 years old, and of adalimumab in patients < 50 years old.

The value of five blood markers in differentiating mycosis fungoides and Sézary syndrome: a validation cohort

BACKGROUND

Clinical and histological diagnosis of Sézary syndrome (SS) and mycosis fungoides (MF) is challenging in clinical routine.

OBJECTIVES

We investigated five blood markers previously described for SS (T-plastin, Twist, KIR3DL2, NKp46 and Tox) in a prospective validation cohort of patients.

METHODS

We included 447 patients in this study and 107 patients were followed up for prognosis. The markers were analysed by reverse transcriptase quantitative real-time polymerase chain reaction (RT-qPCR) on peripheral blood leucocytes and CD4⁺ T cells in a cohort of consecutive patients with early MF, erythrodermic MF and SS and compared with patients presenting with benign inflammatory dermatoses (BID) and erythrodermic BID. The markers were assessed in parallel to gold standard values such as CD4/CD8 ratio, loss of CD7 and CD26 membrane expression and CD4 absolute values. Sensitivity and specificity were analysed by receiver operator characteristic curves. The prognostic value of selected markers was analysed on a subset of patients. This study was conducted in one centre.

RESULTS

We defined cut-off values for each marker. T-plastin, Twist and KIR3DL2 had the best validity. SS may be overrepresented. The combination of T-plastin and Twist was able to differentiate between erythrodermic MF or BID and SS. The additional analysis of KIR3DL2 may be useful to predict the prognosis.

CONCLUSIONS

We propose T-plastin, Twist and KIR3DL2 measured by RT-qPCR as new diagnostic markers for Sézary syndrome.

Evaluation and application of a new scintillator-based heat-resistant back-scattered electron detector during heat treatment in the scanning electron microscope

A new high-temperature detector dedicated to the collection of backscattered electrons is used in combination with heating stages up to 1050°C, in high-vacuum and low-vacuum modes in order to evaluate its possibilities through signal-to-noise ration measurements and different applications. Four examples of material transformations occurring at high temperature are herein reported: grain growth during annealing of a rolled platinum foil, recrystallisation of a multiphased alloy, oxidation of a Ni-based alloy and complex phase transformations occurring during the annealing of an Al-Si coated boron steel. The detector could be potentially adapted to any type of SEM and it offers good opportunities to perform high-temperature experiments in various atmospheres.

Reconceptualizing Parental Leave Benefits in COVID-19 Canada: From Employment Policy to Care and Social Protection Policy

Although the coronavirus disease 2019 (COVID-19) pandemic has spurred critical and much-needed attention to re-thinking policy approaches to child care and long-term elder care, little focus has been given to its implications for parental leave policies and parental benefits for the care of infants and young children. This article is about reconceptualizing and reconfiguring employment-based parental leave policies in Canada both during and after COVID-19. Informed by theoretical insights from the fields of care economies, feminist political economy, and care and social reproduction and by national and international parental leave research, we argue that it is time to reconceptualize parental leave benefits not only as employment policy but also as a care and social protection policy. To make this shift, we explore three topic areas: a mixed system of parental benefits that combine employment-based and citizenship-based entitlements, connections between policy design and gender equality, and the need for robust intersectional data to track which Canadian families are receiving parental benefits.

Abstract 4325: A Phase II exploratory study to identify biomarkers prognostic of clinical response to regorafenib in patients with metastatic colorectal cancer who have failed first-line therapy

Single-agent regorafenib is approved in Canada and in the US for patients with metastatic colorectal cancer (mCRC) who have failed previous lines of therapy1. Identification of prognostic biomarkers is crucial to ensure the best therapeutic strategies for mCRC patients. The goal of this clinical study (NCT01949194) was to explore putative molecular signatures of response and resistance to regorafenib in metastatic tumors and serial blood samples. We used a multi-omics approach to profile metastatic tumor tissues and serial blood samples from 47 mCRC patients who received single-agent regorafenib as second-line therapy after failing first-line therapy with an oxaliplatin or irinotecan-containing regimen with or without bevacizumab. Whole exome sequencing was performed to assess both the mutational and copy number (CN) landscapes of metastatic tissues from 29 patients and the transcriptome was interrogated using RNA sequencing. A 14-gene panel was used to profile serial plasma samples. Molecular aberrations were then correlated with lesion-specific treatment response using RECIST 1.1 and progression free survival (PFS) to investigate potential associations.The copy number aberration (CNA) landscape of metastatic tumors was assessed using Nexus Copy Number Software and 20 significant focal aberrations were identified using Genomic Identification of Significant Target in Cancer (GISTIC) test (q-bound&lt;0.05). We interrogated all CNA regions across the genome using the log-rank statistic test and identified 38 CNA regions associated with PFS (permutated p-value &lt;0.05). Interestingly, CN gains targeting three genes, GPR52, PTGS2 and MYC, classified within the drug resistance gene category in the drug-interaction database (DGIdb), were associated with a shorter PFS (Kaplan Meier analysis). The mutational landscape showed typical mutation rates for the top 5 driver genes: APC, KRAS, BRAF, PIK3CA and TP53. However, KRAS mutations in exons 12 and 13 appeared enriched in intrinsically resistant lesions compared to stable and acquired resistance lesions (83% versus 41%). At the transcriptome level, three main pathways were associated with intrinsic resistance (TGF-β signaling activation and MAPK activation) and shorter PFS (adherens junction). The profiling of plasma samples showed a higher proportion of samples with non-detectable ctDNA in patients exhibiting longer PFS (PFS ≥ 9 months, 70%) compared to patients with shorter PFS (&lt; 9 months, 18%). This study allowed the identification of several candidate genes and regions at different molecular levels that warrant further validation in order to stratify patients who will likely respond, display intrinsic resistance or develop acquired resistance to regorafenib treatment. 1- Grothey A, Van Cutsem E, Sobrero A, Siena S, Falcone A, Ychou M, et al. Regorafenib monotherapy for previously treated metastatic colorectal cancer (CORRECT): an international, multicentre, randomized, placebo-controlled, phase 3 trial. Lancet. 2013 Jan 26;381(9863):303-12.

Citation Format: Karen Gambaro, Maud Marques, Suzan McNamara, Mathilde Couetoux du Tertre, Cyrla Hoffert, Archana Srivastava, Sophie Mathieu, Anna schab, Thierry Alcindor, Adrian Langleben, Lucas Sideris, Mahmoud Adbelsalam, Mustapha Tehfe, Gerald Batist, Petr Kavan. A Phase II exploratory study to identify biomarkers prognostic of clinical response to regorafenib in patients with metastatic colorectal cancer who have failed first-line therapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4325.

La transformation de l'offre de services de garde au Québec: Une brèche dans la collectivisation du travail de reproduction sociale?

In 1997, the government of Québec instituted a low-cost and universal childcare services program most commonly available through the "centres de la petite enfance (CPE)" (early chilldhood centers). Since 2003, this model is being slowly dismantled on account of an explosion in the number of commercial daycare centers and, since 2015, an adjustment of rates according to family revenues. This research article gathers scattered information about the childcare services offer changes in Québec to demonstrate that tearing down a section of the Québécois family policy lowers the collectivization of social reproductive work.

Ancient acquisition of "alginate utilization loci" by human gut microbiota

In bacteria from the phylum Bacteroidetes, the genes coding for enzymes involved in polysaccharide degradation are often colocalized and coregulated in so-called “polysaccharide utilization loci” (PULs). PULs dedicated to the degradation of marine polysaccharides (e.g. laminaran, ulvan, alginate and porphyran) have been characterized in marine bacteria. Interestingly, the gut microbiome of Japanese individuals acquired, by lateral transfer from marine bacteria, the genes involved in the breakdown of porphyran, the cell wall polysaccharide of the red seaweed used in maki. Sequence similarity analyses predict that the human gut microbiome also encodes enzymes for the degradation of alginate, the main cell wall polysaccharide of brown algae. We undertook the functional characterization of diverse polysaccharide lyases from family PL17, frequently found in marine bacteria as well as those of human gut bacteria. We demonstrate here that this family is polyspecific. Our phylogenetic analysis of family PL17 reveals that all alginate lyases, which have all the same specificity and mode of action, cluster together in a very distinct subfamily. The alginate lyases found in human gut bacteria group together in a single clade which is rooted deeply in the PL17 tree. These enzymes were found in PULs containing PL6 enzymes, which also clustered together in the phylogenetic tree of PL6. Together, biochemical and bioinformatics analyses suggest that acquisition of this system appears ancient and, because only traces of two successful transfers were detected upon inspection of PL6 and PL17 families, the pace of acquisition of marine polysaccharide degradation system is probably very slow.

Angiotensin II Overstimulation Leads to an Increased Susceptibility to Dilated Cardiomyopathy and Higher Mortality in Female Mice

Heart failure (HF) is associated with high mortality and affects men and women differently. The underlying mechanisms for these sex-related differences remain largely unexplored. Accordingly, using mice with cardiac-specific overexpression of the angiotensin II (ANGII) type 1 receptor (AT1R), we explored male-female differences in the manifestations of hypertrophy and HF. AT1R mice of both sexes feature electrical and Ca²⁺ handling alterations, systolic dysfunction, hypertrophy and develop HF. However, females had much higher mortality (21.0%) rate than males (5.5%). In females, AT1R stimulation leads to more pronounced eccentric hypertrophy (larger increase in LV mass/body weight ratio [+31%], in cell length [+27%], in LV internal end-diastolic [LVIDd, +34%] and systolic [LVIDs, +67%] diameter) and dilation (larger decrease in LV posterior wall thickness, +17%) than males. In addition, in female AT1R mice the cytosolic Ca²⁺ extrusion mechanisms were more severely compromised and were associated with a specific increased in Ca²⁺ sparks (by 187%) and evidence of SR Ca²⁺ leak. Altogether, these results suggest that female AT1R mice have more severe eccentric hypertrophy, dysfunction and compromised Ca²⁺ dynamics. These findings indicate that females are more susceptible to the adverse effects of AT1R stimulation than males favouring the development of HF and increased mortality.

A risk-based, product-level approach for assuring aquatic environmental safety of cleaning products in the context of sustainability: The Environmental Safety Check (ESC) scheme of the A.I.S.E. Charter for Sustainable Cleaning

Cleaning products have long been a focus of efforts to improve sustainability and assure safety for the aquatic environment when disposed of after use. The latter is addressed at ingredient level through environmental risk assessment, including in formal frameworks such as REACH. Nevertheless, in the context of programs to improve overall sustainability, stakeholders demand both environmental safety assurance and progress at product level. Current product-level approaches for aquatic toxicity (e.g., USEtox™, Critical Dilution Volume) can be seen as predominantly hazard-based. The more logical approach would be risk-based, because ecotoxicity is generally threshold-dependent and hazard-based assessment produces conflicts with risk-based learnings. The development of a risk-based approach to assess formulated products is described: the International Association for Soaps, Detergents and Maintenance Products (A.I.S.E.) Charter Environmental Safety Check (ESC), which is consistent with the scientific principles underlying REACH. This is implemented through a simple spreadsheet tool and internal database of ingredient parameters including predicted no-effect concentration (PNEC) and removal rate. A novel feature is applying market volume information for both product types and ingredients to permit a risk-based calculation. To pass the ESC check, the projected environmental safety ratio (PESR) for each ingredient as formulated and dosed (unless cleared by a published risk assessment or exempted as inherently low risk) must be less than 1. The advantages of a risk-based approach are discussed. The strengths and limitations of various possible approaches to standard-setting, product-ranking and driving continuous improvement in respect of potential ecotoxic impacts on the aquatic environment are considered. It is proposed that as ecotoxicity is generally accepted to be threshold-dependent, with no effect below the threshold, the most constructive approach to continuous improvement of sustainability with regard to ecotoxicity is to focus efforts on instances where the safety margins for ingredients as used in specific products are narrow. This necessitates a risk-based approach. Integr Environ Assess Manag 2017;13:127-138. © 2016 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC.

From Peptide Aptamers to Inhibitors of FUR, Bacterial Transcriptional Regulator of Iron Homeostasis and Virulence

FUR (Ferric Uptake Regulator) protein is a global transcriptional regulator that senses iron status and controls the expression of genes involved in iron homeostasis, virulence, and oxidative stress. Ubiquitous in Gram-negative bacteria and absent in eukaryotes, FUR is an attractive antivirulence target since the inactivation of the fur gene in various pathogens attenuates their virulence. The characterization of 13-aa-long anti-FUR linear peptides derived from the variable part of the anti-FUR peptide aptamers, that were previously shown to decrease pathogenic E. coli strain virulence in a fly infection model, is described herein. Modeling, docking, and experimental approaches in vitro (activity and interaction assays, mutations) and in cells (yeast two-hybrid assays) were combined to characterize the interactions of the peptides with FUR, and to understand their mechanism of inhibition. As a result, reliable structure models of two peptide-FUR complexes are given. Inhibition sites are mapped in the groove between the two FUR subunits where DNA should also bind. Another peptide behaves differently and interferes with the dimerization itself. These results define these novel small peptide inhibitors as lead compounds for inhibition of the FUR transcription factor.

Functional Exploration of the Polysaccharide Lyase Family PL6

Alginate, the main cell-wall polysaccharide of brown algae, is composed of two residues: mannuronic acid (M-residues) and, its C5-epimer, guluronic acid (G-residues). Alginate lyases define a class of enzymes that cleave the glycosidic bond of alginate by β-elimination. They are classified according to their ability to recognize the distribution of M- and G-residues and are named M-, G- or MG-lyases. In the CAZy database, alginate lyases have been grouped by sequence similarity into seven distinct polysaccharide lyase families. The polysaccharide lyase family PL6 is subdivided into three subfamilies. Subfamily PL6_1 includes three biochemically characterized enzymes (two alginate lyases and one dermatan sulfatase lyase). No characterized enzymes have been described in the two other subfamilies (PL6_2 and PL6_3). To improve the prediction of polysaccharide-lyase activity in the PL6 family, we re-examined the classification of the PL6 family and biochemically characterized a set of enzymes reflecting the diversity of the protein sequences. Our results show that subfamily PL6_1 includes two dermatan sulfates lyases and several alginate lyases that have various substrate specificities and modes of action. In contrast, subfamilies PL6_2 and PL6_3 were found to contain only endo-poly-MG-lyases.

Clinical recommendations in the management of the patient with type 1 diabetes on insulin pump therapy in the perioperative period: a primer for the anaesthetist

Insulin pump therapy is increasingly common in patients with type 1 diabetes. Many of these patients will require surgery at some point in their lifetime. Few doctors will have experience of managing these patients, and little evidence exists to assist in the development of guidelines for patients with insulin pump therapy, undergoing surgery.It is clear that during emergency surgery insulin pump therapy is not appropriate and should be discontinued, but patients undergoing some elective surgery can and should continue insulin pump therapy, without any adverse effect on their blood sugar control, or on the outcome of their surgery. Individual hospitals need to formalize guidance on the management of patients receiving continuous subcutaneous insulin therapy, to allow patients the choice to continue their therapy during surgery. This expert opinion presents anaesthetists with a suggested clinical framework to help facilitate continued insulin pump therapy, during elective surgery and into the postoperative period.

Reduction in Na(+) current by angiotensin II is mediated by PKCα in mouse and human-induced pluripotent stem cell-derived cardiomyocytes

BACKGROUND

Ventricular arrhythmias and sudden cardiac deaths are among the leading causes of mortality in patients with heart failure, and the underlying mechanisms remain incompletely understood. Chronic elevation of angiotensin II (ANGII) is known to be one of the main contributors to heart failure.

OBJECTIVE

We tested whether ANGII can alter ventricular conduction and Na(+) current using transgenic mice with cardiomyocyte-restricted overexpression of ANGII type 1 receptor (AT1R).

METHODS

We used surface electrocardiograms along with current- and voltage-clamp techniques to characterize the electrophysiological properties of AT1R mice while the underlying regulatory mechanisms were explored using reverse transcription/quantitative polymerase chain reaction, Western blots, and immunofluorescence techniques.

RESULTS

Electrophysiological data indicated that chronic AT1R activation in ventricular myocytes caused a 60% reduction in Na(+) current density that slowed the maximal velocity of the action potential upstroke, leading to a prolongation of the QRS complex. These changes occur independently of cardiac hypertrophy, suggesting a direct role for ANGII/AT1R in slowing ventricular conduction. Western blots demonstrated a selective increase in sarcolemmal protein kinase Cα (PKCα) in AT1R mice, indicating PKCα activation. Furthermore, immunofluorescence analysis showed reorganization of PKCα expression to sarcolemma and colocalization with NaV1.5 in AT1R myocytes. The involvement of PKCα in regulating Na(+) current was subsequently demonstrated in human-induced pluripotent stem cell-derived cardiomyocytes where ANGII treatment reduced Na(+) current density. Concomitant treatment with αV5-3, a PKCα translocation inhibitor peptide, blocked the ANGII effect.

CONCLUSION

Overall, this study suggests that in mouse and human cardiomyocytes, PKCα is an important mediator of the ANGII-induced reduction in Na(+) current and may contribute to ventricular arrhythmias.

Estrogen regulation of the transient outward K(+) current involves estrogen receptor α in mouse heart

BACKGROUND AND OBJECTIVE

We have previously shown that androgens upregulate cardiac K(+) channels and shorten repolarization. However, the effects that estrogens (E2) and estrogen receptors (ER) might have on the various repolarizing K(+) currents and underlying ion channels remain incompletely understood. Accordingly, our objective was to verify whether and how E2 and its ERs subtypes influence these K(+) currents.

METHODS AND RESULTS

In order to examine the influence of E2 and ERs on K(+) currents we drastically lowered the E2 level through ovariectomy (OVX; 74% reduction vs CTL) and in parallel, we used female mice lacking either ERα (ERαKO) or ERβ (ERβKO). In OVX mice, results showed a specific increase of 35% in the density of the Ca(2+)-independent transient outward K(+) current (Ito) compared to CTL. Western blots showed increase in Kv4.2 and Kv4.3 sarcolemmal protein expression while qPCR revealed higher mRNA expression of only Kv4.3 in OVX mice. This upregulation of Ito was correlated with a shorter ventricular action potential duration and QTc interval. In ERαKO but not ERβKO mice, the mRNA of Kv4.3 was selectively increased. Furthermore, when ventricular myocytes obtained from ERαKO and ERβKO were cultured in the presence of E2, results showed that E2 reduced Ito density only in ERβKO myocytes confirming the repressive role of E2-ERα in regulating Ito.

CONCLUSION

Altogether, these results suggest that E2 negatively regulates the density of Ito through ERα, this highlights a potential role for this female hormone and its α-subtype receptor in modulating cardiac electrical activity.

Managing the Risk of Occupational Allergy in the Enzyme Detergent Industry

Enzyme proteins have potential to cause occupational allergy/asthma. Consequently, as users of enzymes in formulated products, detergents manufacturers have implemented a number of control measures to ensure that the hazard does not translate into health effects in the workforce. To that end, trade associations have developed best practice guidelines which emphasize occupational hygiene and medical monitoring as part of an effective risk management strategy. The need for businesses to recognize the utility of this guidance is reinforced by reports where factories which have failed to follow good industrial hygiene practices have given rise to incidences of occupational allergy. In this article, an overview is provided of how the industry guidelines are actually implemented in practice and what experience is to be derived therefrom. Both medical surveillance and air monitoring practices associated with the implementation of industry guidelines at approximately 100 manufacturing facilities are examined. The data show that by using the approaches described for the limitation of exposure, for the provision of good occupational hygiene and for the active monitoring of health, the respiratory allergenic risk associated with enzyme proteins can be successfully managed. This therefore represents an approach that could be recommended to other industries contemplating working with enzymes.

Interleukin-1β reduces L-type Ca2+ current through protein kinase Cϵ activation in mouse heart

Inflammation is now widely recognized as a key component of heart disease. Patients suffering from arrhythmias and heart failure have increased levels of tumor necrosis factor-α (TNFα) and interleukin-1β (IL-1β). Evidence suggests that these cytokines are important mediators of cardiac remodeling; however, their effects on ion channels and arrhythmogenesis remain incompletely understood. The L-type Ca(2+) current (ICaL) is a major determinant of the plateau phase of cardiac action potential and has a critical excitation-contraction coupling role. Thus, altering its properties could have detrimental effects on cardiac electrical and contractile functions. Accordingly, the objective of this study was to elucidate the effect of TNFα and IL-1β on ICaL, while exploring the underlying regulatory mechanisms. Neonatal mouse ventricular myocytes were treated with a pathophysiological concentration (30 pg/ml) of TNFα and IL-1β for 24 h. Voltage-clamp recordings showed that TNFα had no effect on ICaL, whereas IL-1β decreased the current density by 36%. Although both IL-1β- and TNFα-treated myocytes showed significant increase in reactive oxidative species (ROS), Western blot experiments revealed that only IL-1β increased PKCϵ membrane translocation. The antioxidant N-acetyl-L-cysteine normalized ROS levels and restored ICaL density. Furthermore, the PKCϵ translocation inhibitor ϵ-V1-2 blocked the effect of IL-1β on ICaL. The reduction of ICaL by IL-1β was also seen in cultured adult ventricular myocytes. Overall, chronic IL-1β treatment decreased ICaL density in cardiomyocytes. These effects implicated ROS signaling and PKCϵ activation. These findings could contribute to explain the role of IL-1β in the development of arrhythmia and heart failure.