Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

A keystone avian predator faces elevated energy expenditure in a warming Arctic

Climate change is transforming bioenergetic landscapes, challenging behavioral and physiological coping mechanisms. A critical question involves whether animals can adjust behavioral patterns and energy expenditure to stabilize fitness given reconfiguration of resource bases, or whether limits to plasticity ultimately compromise energy balance. In the Arctic, rapidly warming temperatures are transforming food webs, making Arctic organisms strong models for understanding biological implications of climate change-related environmental variability. We examined plasticity in the daily energy expenditure (DEE) of an Arctic seabird, the little auk (Alle alle) in response to variability in climate change-sensitive drivers of resource availability, sea surface temperature (SST) and sea ice coverage (SIC), and tested the hypothesis that energetic ceilings and exposure to mercury, an important neurotoxin and endocrine disrupter in marine ecosystems, may limit scope for plasticity. To estimate DEE, we used accelerometer data obtained across years from two colonies exposed to distinct environmental conditions (Ukaleqarteq (UK), East Greenland; Hornsund (HS), Svalbard). We proceeded to model future changes in SST to predict energetic impacts. At UK, high flight costs linked to low SIC and high SST drove DEE from below to above 4 × basal metabolic rate (BMR), a proposed energetic threshold for breeding birds. However, DEE remained below 7 × BMR, an alternative threshold, and did not plateau. Birds at HS experienced higher, relatively invariable SST, and operated above 4 × BMR. Mercury exposure was unrelated to DEE, and fitness remained stable. Thus, plasticity in DEE currently buffers fitness, providing resiliency against climate change. Nevertheless, modelling suggests that continued warming of SST may promote accelerating increases in DEE, which may become unsustainable. This article is protected by copyright. All rights reserved.

Mercury Contamination Challenges the Behavioral Response of a Keystone Species to Arctic Climate Change

Combined effects of multiple, climate change-associated stressors are of mounting concern, especially in Arctic ecosystems. Elevated mercury (Hg) exposure in Arctic animals could affect behavioral responses to changes in foraging landscapes caused by climate change, generating interactive effects on behavior and population resilience. We investigated this hypothesis in little auks (Alle alle), a keystone Arctic seabird. We compiled behavioral data for 44 birds across 5 years using accelerometers while also quantifying blood Hg and environmental conditions. Warm sea surface temperature (SST) and low sea ice coverage reshaped time activity budgets (TABs) and diving patterns, causing decreased resting, increased flight, and longer dives. Mercury contamination was not associated with TABs. However, highly contaminated birds lengthened interdive breaks when making long dives, suggesting Hg-induced physiological limitations. As dive durations increased with warm SST, subtle toxicological effects threaten to increasingly constrain diving and foraging efficiency as climate change progresses, with ecosystem-wide repercussions.

Carryover effects of winter mercury contamination on summer concentrations and reproductive performance in little auks

Many animals migrate after reproduction to respond to seasonal environmental changes. Environmental conditions experienced on non-breeding sites can have carryover effects on fitness. Exposure to harmful chemicals can vary widely between breeding and non-breeding grounds, but its carryover effects are poorly studied. Mercury (Hg) contamination is a major concern in the Arctic. Here, we quantified winter Hg contamination and its carryover effects in the most abundant Arctic seabird, the little auk Alle alle. Winter Hg contamination of birds from an East Greenland population was inferred from head feather concentrations. Birds tracked with Global Location Sensors (GLS, N = 28 of the total 92) spent the winter in western and central North Atlantic waters and had increasing head feather Hg concentrations with increasing longitude (i.e., eastward). This spatial pattern was not predicted by environmental variables such as bathymetry, sea-surface temperature or productivity, and needs further investigation. Hg concentrations in head feathers and blood were strongly correlated, suggesting a carryover effect of adult winter contamination on the consequent summer concentrations. Head feather Hg concentrations had no clear association with telomere length, a robust fitness indicator. In contrast, carryover negative effects were detected on chick health, as parental Hg contamination in winter was associated with decreasing growth rate of chicks in summer. Head feather Hg concentrations of females were not associated with egg membrane Hg concentrations, or with egg volume. In addition, parental winter Hg contamination was not related to Hg burdens in chicks' body feathers. Therefore, we hypothesise that the association between parental winter Hg exposure and the growth of their chick results from an Hg-related decrease in parental care, and needs further empirical evidence. Our results stress the need of considering parental contamination on non-breeding sites to understand Hg trans-generational effects in migrating seabirds, even at low concentrations.

Spatial variations in winter Hg contamination affect egg volume in an Arctic seabird, the great skua (Stercorarius skua)

Knowledge of the ecology and at-sea distribution of migratory species like seabirds has substantially increased over the last two decades. Furthermore, an increasing number of studies have recently focused on chemical contamination of birds over their annual cycle. However, the understanding of the combined effects of spatial movements and contamination on seabirds' life-history traits is still scarce. During winter, seabirds can use very different areas, at the large-scale. Such overwintering strategies and distribution may expose individuals to contrasting environmental stressors, including pollutants. Here, we studied the winter distribution and contamination with mercury (Hg), and their combined effects on reproduction, in a great skua (Stercorarius skua) population breeding in Bjørnøya, Svalbard. We confirmed that individuals of this specific population overwinter in three different areas of the North Atlantic, namely Africa, Europe and northwest Atlantic. The highest Hg concentrations in feathers were measured in great skuas wintering off Europe (Linear Mixed Models - mean value ± SD = 10.47 ± 3.59 μg g ^-1 dw), followed by skuas wintering in northwest Atlantic (8.42 ± 3.70) and off Africa (5.52 ± 1.83). Additionally, we found that female winter distribution and accumulated Hg affected the volume of their eggs (Linear Mixed Models), but not the number of laid and hatched eggs (Kruskal-Wallis tests). This study provides new insights on the contamination risks that seabirds might face according to their overwinter distribution and the possible associated carry-over effects.

Mercury contamination and potential health risks to Arctic seabirds and shorebirds

Since the last Arctic Monitoring and Assessment Programme (AMAP) effort to review biological effects of mercury (Hg) on Arctic biota in 2011 and 2018, there has been a considerable number of new Arctic bird studies. This review article provides contemporary Hg exposure and potential health risk for 36 Arctic seabird and shorebird species, representing a larger portion of the Arctic than during previous AMAP assessments now also including parts of the Russian Arctic. To assess risk to birds, we used Hg toxicity benchmarks established for blood and converted to egg, liver, and feather tissues. Several Arctic seabird populations showed Hg concentrations that exceeded toxicity benchmarks, with 50 % of individual birds exceeding the "no adverse health effect" level. In particular, 5 % of all studied birds were considered to be at moderate or higher risk to Hg toxicity. However, most seabirds (95 %) were generally at lower risk to Hg toxicity. The highest Hg contamination was observed in seabirds breeding in the western Atlantic and Pacific Oceans. Most Arctic shorebirds exhibited low Hg concentrations, with approximately 45 % of individuals categorized at no risk, 2.5 % at high risk category, and no individual at severe risk. Although the majority Arctic-breeding seabirds and shorebirds appeared at lower risk to Hg toxicity, recent studies have reported deleterious effects of Hg on some pituitary hormones, genotoxicity, and reproductive performance. Adult survival appeared unaffected by Hg exposure, although long-term banding studies incorporating Hg are still limited. Although Hg contamination across the Arctic is considered low for most bird species, Hg in combination with other stressors, including other contaminants, diseases, parasites, and climate change, may still cause adverse effects. Future investigations on the global impact of Hg on Arctic birds should be conducted within a multi-stressor framework. This information helps to address Article 22 (Effectiveness Evaluation) of the Minamata Convention on Mercury as a global pollutant.

Quasicontinuous Exhaust Scenario for a Fusion Reactor: The Renaissance of Small Edge Localized Modes

Tokamak operational regimes with small edge localized modes (ELMs) could be a solution to the problem of large transient heat loads in fusion reactors. A ballooning mode near the last closed flux surface governed by the pressure gradient and the magnetic shear there has been proposed for small ELMs. In this Letter, we experimentally investigate several stabilizing effects near the last closed flux surface and present linear ideal simulations that indeed develop ballooninglike fluctuations there and connect them with nonlinear resistive simulations. The dimensionless parameters of the small ELM regime in the region of interest are very similar to those in a reactor, making this regime the ideal exhaust scenario for a future device.

Monobody adapter for functional antibody display on nanoparticles for adaptable targeted delivery applications

Vascular endothelial cells (ECs) play a central role in the pathophysiology of many diseases. The use of targeted nanoparticles (NPs) to deliver therapeutics to ECs could dramatically improve efficacy by providing elevated and sustained intracellular drug levels. However, achieving sufficient levels of NP targeting in human settings remains elusive. Here, we overcome this barrier by engineering a monobody adapter that presents antibodies on the NP surface in a manner that fully preserves their antigen-binding function. This system improves targeting efficacy in cultured ECs under flow by >1000-fold over conventional antibody immobilization using amine coupling and enables robust delivery of NPs to the ECs of human kidneys undergoing ex vivo perfusion, a clinical setting used for organ transplant. Our monobody adapter also enables a simple plug-and-play capacity that facilitates the evaluation of a diverse array of targeted NPs. This technology has the potential to simplify and possibly accelerate both the development and clinical translation of EC-targeted nanomedicines.

Highlighting the positive aspects of being a PhD student

Articles about doing a PhD tend to focus on the difficulties faced by research students. Here we argue that the scientific community should also highlight the positive elements of the PhD experience.

Biological invasion costs reveal insufficient proactive management worldwide

The global increase in biological invasions is placing growing pressure on the management of ecological and economic systems. However, the effectiveness of current management expenditure is difficult to assess due to a lack of standardised measurement across spatial, taxonomic and temporal scales. Furthermore, there is no quantification of the spending difference between pre-invasion (e.g. prevention) and post-invasion (e.g. control) stages, although preventative measures are considered to be the most cost-effective. Here, we use a comprehensive database of invasive alien species economic costs (InvaCost) to synthesise and model the global management costs of biological invasions, in order to provide a better understanding of the stage at which these expenditures occur. Since 1960, reported management expenditures have totalled at least US$95.3 billion (in 2017 values), considering only highly reliable and actually observed costs - 12-times less than damage costs from invasions ($1130.6 billion). Pre-invasion management spending ($2.8 billion) was over 25-times lower than post-invasion expenditure ($72.7 billion). Management costs were heavily geographically skewed towards North America (54%) and Oceania (30%). The largest shares of expenditures were directed towards invasive alien invertebrates in terrestrial environments. Spending on invasive alien species management has grown by two orders of magnitude since 1960, reaching an estimated $4.2 billion per year globally (in 2017 values) in the 2010s, but remains 1-2 orders of magnitude lower than damages. National management spending increased with incurred damage costs, with management actions delayed on average by 11 years globally following damage reporting. These management delays on the global level have caused an additional invasion cost of approximately $1.2 trillion, compared to scenarios with immediate management. Our results indicate insufficient management - particularly pre-invasion - and urge better investment to prevent future invasions and to control established alien species. Recommendations to improve reported management cost comprehensiveness, resolution and terminology are also made.

O-214 Undisturbed embryo culture under High Humidity atmosphere in a time-lapse system increases pregnancy rates

Study question

Does culture in high relative humidity conditions (HC) improve pregnancy rates when using a time-lapse system (TLS) and single-step (SS) culture medium?

Summary answer

Using an integrated-TLS and SS medium, culture under HC increases the likelihood of embryos to achieve a pregnancy with respect to those cultured in DC.

What is known already

Many variables affect embryo development, and need to be precisely tuned in every IVF laboratory, especially inside the incubators. TLS provide stability during embryo culture, which is a well-known key factor for a proper embryo development. The humidity content of culture atmosphere is especially relevant in order to avoid oscillations in culture media osmolality. It has been previously reported that culture under HC has a significant effect on embryo quality and morphokinetics. However, studies assessing the effect of HC in clinical outcome are rare and inconclusive, mostly due to the variability in the incubator device used and insufficient sample size.

Study design, size, duration

The present is a retrospective study performed over 1624 ICSI treatments from 3 fertility clinics from December 2017 to October 2020. Zygote cohorts were randomly assigned to dry (N = 794) or humid conditions (N = 830). It includes autologous treatments with (N = 555) and without (N = 368) pre-implantation genetic testing (PGT) and egg donation treatments (N = 701). Following selection by combining morphological and morphokinetic criteria, 1611 mostly single embryo transfers (92%) were performed, 779 from DC and 832 from HC.

Participants/materials, setting, methods

Stimulation, oocyte pickup and fertilization were performed according to the standard procedures of the clinic. We used a GERI incubator (Genea Biomedx), with 6 separated chambers for individual patients, 3 of them configured to work in DC, and 3 in HC. Embryos were cultured in specific 16-well GERI trays with single-step Gems® culture medium (Genea Biomedx). The effect of HC in pregnancy rate was assessed by multivariate logistic regression and Pearson Chi Square Test.

Main results and the role of chance

Types of treatment and patient demographics were homogeneously distributed in the two study groups. Mean patient age was 39.88±4.47 years, BMI: 23.54±4.21 Kg/m2 and number of correctly fertilized oocytes: 7.86±3.87. A logistic regression was performed, including other possible affecting factors: ovum age and origin, transfer day, fresh or frozen-warmed embryo transfer, number of transferred embryos and the use of PGT. Said analysis revealed that embryos cultured in HC are more likely to achieve a pregnancy than those cultured in DC (OR = 1.30, 95% CI (1.05-1.59), p=0.014). Pregnancy rate was significantly higher in HC (66.7%) than in DC (60.9%) in the total embryo transfers (p = 0.017). Pregnancy rate was also higher in HC in fresh embryo transfers (68.6% in HC vs 63.2% in DC; p = 0.133) and frozen-thawed transfers (65.2% in HC vs 59.1% in DC; p = 0.062), although differences were not statistically significant due to the reduced sample size. Stratifying the results, the significant difference remained in transfers belonging to autologous cycles (68.4% HC vs 56.5% in DC; p = 0.030) and in treatments in which PGT was performed (67.1% HC vs 56.0% in DC; p = 0.023), but the difference in egg donation procedures was not statistically significant (66.4% in HC vs 64.7% in DC, p = 0.577).

Limitations, reasons for caution

This is a retrospective analysis performed over the clinics’ treatments, so it might be compromised by some bias, although multivariable analysis may overcome them. For further assessing the effect of HC in clinical results a prospective controlled study, with a larger sample size could be performed, also comparing life-birth rates.

Wider implications of the findings

These results, alongside our previous findings (Valera et al. 2020, Albert et al. 2020), support that HC contributes to optimize embryo development and clinical results in undisturbed culture in TLS with single-step medium. To our knowledge, this is the largest study on the matter and the first performing multivariable analysis.

Trial registration number

Not applicable

Seasonal variation of mercury contamination in Arctic seabirds: A pan-Arctic assessment

Mercury (Hg) is a natural trace element found in high concentrations in top predators, including Arctic seabirds. Most current knowledge about Hg concentrations in Arctic seabirds relates to exposure during the summer breeding period when researchers can easily access seabirds at colonies. However, the few studies focused on winter have shown higher Hg concentrations during the non-breeding period than breeding period in several tissues. Hence, improving knowledge about Hg exposure during the non-breeding period is crucial to understanding the threats and risks encountered by these species year-round. We used feathers of nine migratory alcid species occurring at high latitudes to study bird Hg exposure during both the breeding and non-breeding periods. Overall, Hg concentrations during the non-breeding period were ~3 times higher than during the breeding period. In addition, spatial differences were apparent within and between the Atlantic and Pacific regions. While Hg concentrations during the non-breeding period were ~9 times and ~3 times higher than during the breeding period for the West and East Atlantic respectively, Hg concentrations in the Pacific during the non-breeding period were only ~1.7 times higher than during the breeding period. In addition, individual Hg concentrations during the non-breeding period for most of the seabird colonies were above 5 μg g^-1 dry weight (dw), which is considered to be the threshold at which deleterious effects are observed, suggesting that some breeding populations might be vulnerable to non-breeding Hg exposure. Since wintering area locations, and migration routes may influence seasonal Hg concentrations, it is crucial to improve our knowledge about spatial ecotoxicology to fully understand the risks associated with Hg contamination in Arctic seabirds.

A risk assessment of the effects of mercury on Baltic Sea, Greater North Sea and North Atlantic wildlife, fish and bivalves

A wide range of species, including marine mammals, seabirds, birds of prey, fish and bivalves, were investigated for potential population health risks resulting from contemporary (post 2000) mercury (Hg) exposure, using novel risk thresholds based on literature and de novo contamination data. The main geographic focus is on the Baltic Sea, while data from the same species in adjacent waters, such as the Greater North Sea and North Atlantic, were included for comparative purposes. For marine mammals, 23% of the groups, each composing individuals of a specific sex and maturity from the same species in a specific study region, showed Hg-concentrations within the High Risk Category (HRC) and Severe Risk Category (SRC). The corresponding percentages for seabirds, fish and bivalves were 2.7%, 25% and 8.0%, respectively, although fish and bivalves were not represented in the SRC. Juveniles from all species showed to be at no or low risk. In comparison to the same species in the adjacent waters, i.e. the Greater North Sea and the North Atlantic, the estimated risk for Baltic populations is not considerably higher. These findings suggest that over the past few decades the Baltic Sea has improved considerably with respect to presenting Hg exposure to its local species, while it does still carry a legacy of elevated Hg levels resulting from high neighbouring industrial and agricultural activity and slow water turnover regime.

Contrasting Spatial and Seasonal Trends of Methylmercury Exposure Pathways of Arctic Seabirds: Combination of Large-Scale Tracking and Stable Isotopic Approaches

Despite the limited direct anthropogenic mercury (Hg) inputs in the circumpolar Arctic, elevated concentrations of methylmercury (MeHg) are accumulated in Arctic marine biota. However, the MeHg production and bioaccumulation pathways in these ecosystems have not been completely unraveled. We measured Hg concentrations and stable isotope ratios of Hg, carbon, and nitrogen in the feathers and blood of geolocator-tracked little auk Alle alle from five Arctic breeding colonies. The wide-range spatial mobility and tissue-specific Hg integration times of this planktivorous seabird allowed the exploration of their spatial (wintering quarters/breeding grounds) and seasonal (nonbreeding/breeding periods) MeHg exposures. An east-to-west increase of head feather Hg concentrations (1.74-3.48 μg·g^-1) was accompanied by significant spatial trends of Hg isotope (particularly Δ¹⁹⁹Hg: 0.96-1.13‰) and carbon isotope (δ¹³C: -20.6 to -19.4‰) ratios. These trends suggest a distinct mixing/proportion of MeHg sources between western North Atlantic and eastern Arctic regions. Higher Δ¹⁹⁹Hg values (+0.4‰) in northern colonies indicate an accumulation of more photochemically impacted MeHg, supporting shallow MeHg production and bioaccumulation in high Arctic waters. The combination of seabird tissue isotopic analysis and spatial tracking helps in tracing the MeHg sources at various spatio-temporal scales.

FRI0095 SARILUMAB IMPROVED PATIENT-PERCEIVED IMPACT OF RHEUMATOID ARTHRITIS WHATEVER THE BASELINE DISEASE ACTIVITY: FIRST RESULTS FROM AN INTERVENTIONAL NON CONTROLLED STUDY: SARIPRO, IN MODERATE AND SEVERE RHEUMATOID ARTHRITIS PATIENTS

Background:

Sarilumab, an anti-IL-6R antibody, is approved for the treatment of moderate to severe RA and shown efficacy on disease activity and patient-reported outcomes (PROs). Detailed analyses of drug efficacy from the patient point of view is important. SariPRO is a pragmatic interventional study close to the daily practice.

Objectives:

To assess the effectiveness of sarilumab on several PROs using the RAID (Rheumatoid Arthritis Impact of Disease) score.

Methods:

The SariPRO study (NCT 03449758) was a French multicenter interventional study assessing the effects of sarilumab 200 mg on PROs in patients with moderately to severely active RA with an inadequate response or intolerance to conventional synthetic or biologic DMARDs. The primary endpoint was change in total RAID score from baseline to week 24 (RAID ranges 0-10 where 10 is maximal impact). Changes from baseline for RAID, DAS28-ESR and CDAI according to baseline disease activity were analyzed as secondary outcomes. Safety was assessed by monitoring adverse events (AE). All statistical analyses were descriptive, 95% CI was given when appropriate.

Results:

84 patients were included in 31 centers and 62 were evaluable and analyzed for effectiveness. They had similar characteristics to the 84 patients at baseline and were as expected for an RA population initiating a biologic: mean (SD) age: 59.9 (12.4) years, 71.0% female, disease duration 9.7 (10.3) years, rheumatoid factor positivity 82.5%, ACPA positivity 86.4%, and DAS28=4.9 (11). Total RAID score decreased significantly from 5.7 (2.0) at baseline to 3.3 (2.5) at W24; mean change was -2.4 [95% CI: -3.0; -1.8]. Furthermore, this improvement was noted both for highly and less active patients at baseline: for patients with DAS28-ESR < 5.1 (n=31), mean change was -1.56 [-2.28; -0.83] and for patients with DAS28-ESR≥5.1 (n=27), mean change was -1.98 [-2.91; -1.05]. Changes in DAS28-ESR and CDAI were significant (-2.8 [-3.2; -2.4] and -15.2 [-18.5; -11.8], respectively). AEs were consistent with the safety profile of anti-IL-6R antibodies and with results from RCTs (data not shown).

Conclusion:

In this real world study, treatment with sarilumab during 24 weeks in RA patients led to an improvement in the total RAID score irrespective of baseline levels of disease activity. This is the first time RAID score is used as the primary endpoint in a study.

References:

[1]Study was sponsored by Sanofi Genzyme

Disclosure of Interests:

Laure Gossec Grant/research support from: Lilly, Mylan, Pfizer, Sandoz, Consultant of: AbbVie, Amgen, Biogen, Celgene, Janssen, Lilly, Novartis, Pfizer, Sandoz, Sanofi-Aventis, UCB, René-Marc Flipo Consultant of: Johnson and Johnson, MSD France, Novartis, Sanofi, Speakers bureau: Johnson and Johnson, MSD France, Novartis, Sanofi, Thierry Schaeverbeke: None declared, Christine Albert: None declared, Athan Baillet Consultant of: Athan BAILLET has received honorarium fees from Abbvie for his participation as the coordinator of the systematic literature review, marie-Christophe Boissier: None declared, Cyrille Confavreux: None declared, Gregoire CORMIER: None declared, Emmanuelle Dernis Speakers bureau: Lilly, Novartis, Elisabeth Gervais Solau: None declared, Sophie Godot: None declared, Jacques-Eric Gottenberg Grant/research support from: BMS, Pfizer, Consultant of: BMS, Sanofi-Genzyme, UCB, Speakers bureau: Abbvie, Eli Lilly and Co., Roche, Sanofi-Genzyme, UCB, Philippe Goupille Grant/research support from: AbbVie, Amgen, Biogen, BMS, Celgene, Chugai, Lilly, Janssen, Medac, MSD France, Nordic Pharma, Novartis, Pfizer, Sanofi and UCB, Consultant of: AbbVie, Amgen, Biogen, BMS, Celgene, Chugai, Lilly, Janssen, Medac, MSD France, Nordic Pharma, Novartis, Pfizer, Sanofi and UCB, Speakers bureau: AbbVie, Amgen, Biogen, BMS, Celgene, Chugai, Lilly, Janssen, Medac, MSD France, Nordic Pharma, Novartis, Pfizer, Sanofi and UCB, Slim Lassoued: None declared, Thierry Lequerre: None declared, Frederic Lioté Consultant of: CME: Nordic Pharma, Christian Marcelli: None declared, Yves Maugars: None declared, Minh Nguyen: None declared, Aleth Perdriger: None declared, Yves-Marie Pers: None declared, Edouard Pertuiset: None declared, Lucile Poiroux: None declared, Carole Rosenberg: None declared, Christian Roux: None declared, Adeline Ruyssen-Witrand Grant/research support from: Abbvie, Pfizer, Consultant of: Abbvie, BMS, Lilly, Mylan, Novartis, Pfizer, Sandoz, Sanofi-Genzyme, Martin SOUBRIER: None declared, Pascale Vergne-Salle: None declared, Charles Zarnitsky: None declared, Eric Fakra Consultant of: Janssen, Lundbeck, Otsuka, Sanofi, Hubert MAROTTE Grant/research support from: Bristol Myers Sqibb, Lilly France, MSD, Novartis, Nordic Pharma, Pfizer, SanofiAventis, Consultant of: AbbVie, Amgen, Bristol Myers Sqibb, Lilly France, MSD, Novartis, Nordic Pharma, Pfizer, SanofiAventis, Paid instructor for: Sanofi-Aventis, Speakers bureau: Sanofi-Aventis, Florence E Lévy-Weil Employee of: Sanofi Genzyme employee

Using blood and feathers to investigate large-scale Hg contamination in Arctic seabirds: A review

Mercury (Hg), because of its deleterious effects on wildlife and its high concentrations in polar regions, has been widely studied in the Arctic. This provided important information regarding food web contamination, spatial and temporal trends of Hg in ecosystems or risk assessments for wildlife and Humans. Among the Arctic biota, seabirds have been among the most studied species due to their sensitivity to this toxicant, their role as bioindicators of the contamination status of their environment, and their consumption by Arctic communities. However, most studies that investigated Hg in Arctic seabirds focused on measurements in internal organs or in eggs, while few investigations have been performed on blood and feathers, despite the relevant and complementary information they provide. Here, we first provide a detailed overview of the specific information blood and feathers can bring when investigating Hg contamination of Arctic seabirds, including new knowledge on the poorly studied non-breeding period. Second, we perform a comprehensive review of the use of blood and feathers as non-lethal tissues to study Hg in Arctic seabirds. This review demonstrates important interspecific variations in Hg blood concentrations according to seabird trophic status, with seaducks generally presenting the lowest Hg concentrations while auks have the highest ones. However, all the observed Hg concentrations are below the admitted toxicity thresholds. Hg concentrations in feathers follow similar trends and gulls appear to be the most contaminated species, likely as a consequence of contrasting migratory and overwintering strategies. This review also confirms strong spatial variations with higher concentrations found in the Canadian Arctic and Pacific waters than in Greenland and the European Arctic. It also identifies some major understudied areas such as West Greenland, Aleutian Islands and Russia. Finally, we provide a thorough review of the current knowledge regarding molting patterns in Arctic seabirds, which is an essential information to interpret Hg concentrations measured in feathers. Overall, our results point out the importance of blood and feathers in seabird ecotoxicological assessments and highlight the need for large scale international collaborations and research programs.

The twenty most charismatic species

Charisma is a term commonly used in conservation biology to describe species. However, as the term "charismatic species" has never been properly defined, it needs to be better characterized to fully meet its potential in conservation biology. To provide a more complete depiction, we collected information from four different sources to define the species currently considered to be the most charismatic and to understand what they represent to the Western public. First, we asked respondents of two separate surveys to identify the 10 animal species that they considered to be the most charismatic and associate them with one to six traits: Rare, Endangered, Beautiful, Cute, Impressive, and Dangerous. We then identified the wild animals featured on the website homepages of the zoos situated in the world's 100 largest cities as well as on the film posters of all Disney and Pixar films, assuming in both cases that the most charismatic species were generally chosen to attract viewers. By combining the four approaches, we set up a ranked list of the 20 most charismatic animals. The majority are large exotic, terrestrial mammals. These species were deemed charismatic, mainly because they were regarded as beautiful, impressive, or endangered, although no particular trait was discriminated, and species were heterogeneously associated with most of the traits. The main social characteristics of respondents did not have a significant effect on their choices. These results provide a concrete list of the most charismatic species and offer insights into the Western public's perception of charismatic species, both of which could be helpful to target new species for conservation campaigns.

The paradoxical extinction of the most charismatic animals

A widespread opinion is that conservation efforts disproportionately benefit charismatic species. However, this doesn't mean that they are not threatened, and which species are "charismatic" remains unclear. Here, we identify the 10 most charismatic animals and show that they are at high risk of imminent extinction in the wild. We also find that the public ignores these animals' predicament and we suggest it could be due to the observed biased perception of their abundance, based more on their profusion in our culture than on their natural populations. We hypothesize that this biased perception impairs conservation efforts because people are unaware that the animals they cherish face imminent extinction and do not perceive their urgent need for conservation. By freely using the image of rare and threatened species in their product marketing, many companies may participate in creating this biased perception, with unintended detrimental effects on conservation efforts, which should be compensated by channeling part of the associated profits to conservation. According to our hypothesis, this biased perception would be likely to last as long as the massive cultural and commercial presence of charismatic species is not accompanied by adequate information campaigns about the imminent threats they face.

Serum levels for midkine, a heparin-binding growth factor, inversely correlate with angiotensin and endothelin receptor autoantibody titers in patients with macroangiopathy

AIM

Peripheral artery disease results in impaired blood flow to the extremities, most often as a consequence of atherosclerotic disease. The hallmark of atherosclerosis is chronic inflammation in the vessel wall. The renin-angiotensin and endothelin systems are considered important pathophysiological effectors. Midkine, a multifunctional cytokine, fulfils different roles in inflammation and promotion of neoangiogenesis. The aim of this study was to assess whether circulating midkine serum levels in patients with peripheral artery disease correlate with established atherosclerosis risk factors, as well as titers of functional autoantibodies directed against receptors of the renin-angiotensin and endothelin system.

METHODS

Clinical data, laboratory values and serum samples from 118 patients operated on for severe peripheral artery disease, and from 100 healthy blood donors were collected. Serum samples were analysed for midkine concentrations as well as autoantibody titers against angiotensin II type 1 and endothelin-1 type A receptors.

RESULTS

Midkine values were significantly higher in the study population than in healthy controls (P<0.001). Circulating midkine levels did not correlate with neither of the traditional risk factors age, sex, obesity, smoking, hypertension, high cholesterol levels, or diabetes mellitus. An unexpected inverse correlation was found with the autoantibodies against angiotensin II type 1 receptor (P<0.05) and endothelin-1 type A receptor (P<0.01).

CONCLUSION

The high levels of midkine in severe peripheral artery disease patients introduce this cytokine as a possible novel effector in the advanced atherosclerotic process. These results also suggest a functional link between vascular receptor autoantibody formation and down-regulated midkine serum levels, that may be relevant in the pathogenesis of clinically relevant peripheral artery occlusive disease.

Mechanical characterization of fourth generation composite humerus

Mechanical data on upper extremity surrogate bones, supporting use as biomechanical tools, is limited. The objective of this study was to characterize the structural behaviour of the fourth-generation composite humerus under simulated physiologic bending, specifically, stiffness, rigidity, and mid-diaphysial surface strains. Three humeri were tested in four-point bending, in anatomically defined anteroposterior (AP) and mediolateral (ML) planes. Stiffness and rigidity were derived using load–displacement data. Principal strains were determined at the anterior, posterior, medial, and lateral surfaces in the humeral mid-diaphysial transverse plane of one specimen using stacked rosettes. Linear structural behaviour was observed within the test range. Average stiffness and rigidity were greater in the ML (918 ± 18 N/mm; 98.4 ± 1.9 Nm2) than the AP plane (833 ± 16 N/mm; 89.3 ± 1.6 Nm2), with little inter-specimen variability. The ML/AP rigidity ratio was 1.1. Surface principal strains were similar at the anterior (5.41 µε/N) and posterior (5.43 µε/N) gauges for AP bending, and comparatively less for ML bending, i.e. 5.1 and 4.5 µε/N, at the medial and lateral gauges, respectively. This study provides novel strain and stiffness data for the fourth-generation composite humerus and also adds to published construct rigidity data. The presented results support the use of this composite bone as a tool for modelling and experimentation.

Plant response traits mediate the effects of subalpine grasslands on soil moisture

* In subalpine grasslands, changes in abiotic conditions with decreased management intensity alter the functional composition of plant communities, leading to modifications of ecosystem properties. Here, it is hypothesized that the nature of plant feedbacks on soil moisture is determined by the values of key traits at the community level. * As community functional parameters of grasslands change along a gradient of land uses, those traits that respond most to differences in abiotic conditions produced by land use changes were identified. A vegetation removal experiment was then conducted to determine how each plant community affected soil moisture. * Soil moisture was negatively correlated with community root length and positively correlated with canopy height, whereas average leaf area was associated with productivity. These traits were successfully used to predict the effects on soil moisture of each plant community in the removal experiment. This result was validated using data from an additional set of fields. * These findings demonstrate that the modification of soil moisture following land use change in subalpine grasslands can be mediated through those plant functional traits that respond to water availability.