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Within the group of antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitides, granulomatosis with polyangiitis (GPA) is the most frequent. The incidence is around 10 to 20 cases/million/year. Clinical manifestations are varied, with ENT, lungs and kidneys most frequently involved. ANCA are pathogenic by triggering neutrophil activation, which leads to vascular damage. Detection of ANCA is most helpful in establishing the diagnosis, but serology may be negative in GPA limited to the airways. Diagnostic work-up and therapy require a multidisciplinary approach. Treatment includes an induction and maintenance phase, combining corticosteroids and immunosuppressive drugs. It aims at limiting the risk of relapses, which is important in GPA, and at reducing corticosteroids toxicity.

Anti-glomerular basement membrane disease is a rare disease. In its classical presentation it associates rapidly progressive glomerulonephritis and diffuse alveolar hemorrhage, linked to the presence of antibodies targeting type IV collagen in the glomerular and alveolar basal membrane. Anti-GBM disease warrants prompt medical management to limit permanent kidney damage and mortality. Treatment includes plasma exchanges to quickly remove pathogenic antibodies and immunosuppressants to stop their production. This article reviews the pathogenesis and current treatments.

Northern Chile sets an ideal laboratory to perform seismic experiments to better understand the subduction process in highly erosive margins. The Taltal segment (~22°S - ~26°S) has been subject of notable scientific attention; however, previous studies have mainly focused on the areas affected by large earthquakes, leaving unattended the processes in the overriding plate. By benefiting from a large temporary network of 84 short-period geophones and the high rate of seismicity in the region, we tectonically characterize the Taltal segment by deriving regional 3D Vp, Vs, and Vp/Vs velocity models, a seismic catalog of 23,000 earthquakes and focal mechanisms for events with M> 4.0. The seismic velocity models illuminate first-order structures such as the Nazca plate, the upper crust of the South American plate, and highlight changes from high to low ratios in the overriding plate that correlate with large-scale structures such as the Atacama fault system (AFS) in the coastline and the West Fault System (WFS) towards the Andes. In terms of the seismicity distribution, we observe a dip change, at intermediate depth (150-200 km), that could be associated with slab-pull activity. Coastal area shows clustered seismicity that might indicate splay faulting reaching the plate interface. Upper-crust activity is mainly related to the AFS and WFS but also to the circulation of fluids around the Lascar volcano. Finally, to get a comprehensive picture of the seismotectonics of the Taltal segment we explore the solutions of focal mechanisms that better describe the type of sources of the earthquakes., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

A thick pamphlet bound in marbled paper. The pamphlet is a "Mémoire sur les États généraux, leurs droits, et la manière de les convoquer."

Determining disease activity in systemic lupus erythematosus (SLE) patients is challenging and limited by the lack of reliable biomarkers. Abnormally activated B cells play a key role in the pathogenesis of SLE, but their measure in clinical practice is currently not recommended. Here, we studied peripheral B cells to identify a valid biomarker. We analyzed peripheral B cells in a discovery cohort of 30 SLE patients compared to 30 healthy controls (HC) using mass cytometry and unsupervised clustering analysis. The relevant B cell populations were subsequently studied by flow cytometry in a validation cohort of 63 SLE patients, 28 autoimmune diseases controls and 39 HC. Our data show an increased frequency of B cell populations with activated phenotype in SLE compared to healthy and autoimmune diseases controls. These cells uniformly lacked the expression of CD21 and CD27. Measurement of CD21 - CD27 - B cells in the blood identified patients with active disease and their frequency correlated with disease severity. Interestingly, we did not observe an increase in the frequency of CD21 - CD27 - B cells in patients with clinically inactive disease but with elevated conventional biomarkers (anti-dsDNA and complement levels). Accordingly, measurement of CD21 - CD27 - B cells represents a robust and easily accessible biomarker to assess the activity of the disease in SLE patients.

Autoimmune hepatitis is a rare disease which can present as acute or chronic forms and can be difficult to diagnose due to its variable clinical presentation. The disease arises in genetically susceptible individuals and several triggers have been identified. The diagnosis is based on the presence of autoantibodies, elevated transaminases and serum immunoglobulin G levels as well as a compatible histology. First-line immunosuppressive treatment strategies lead to clinical remission in most patients. In case of non-response, second-line therapies can be used and in case of hepatocellular insufficiency, liver transplantation remains an excellent option.

Systemic lupus erythematosus is a complex autoimmune disease that remains challenging to treat. Recent advances in the understanding of the pathogenesis of SLE pave the way for the evaluation of biologic medicine. The most promising therapeutic targets in SLE are those that interfere with B cells count or normal function, interferon inhibitors, JAK inhibitors and biologicals that alter the cytokines imbalance that characterizes SLE. Recent phase 3 clinical trials have evaluated the role of belimumab in lupus nephritis and the usefulness of anifrolumab in the treatment of moderate to severe SLE. Many more trials are currently underway and may improve the level of care of patients with SLE in the near future.

Chronic rhinosinusitis with nasal polyps is a severe form of chronic rhinosinusitis, which has a strong negative impact on quality of life. Rhinoscopy is helpful for diagnosis, and initial management depends on intra-nasal corticosteroids and sometimes short-term oral corticosteroids (1 to 3 weeks). If well-conducted drug therapy fails, surgery is considered. In the event of post-surgery recurrence or in case of concomitant severe asthma, biologic therapies represent an interesting option. These drugs include dupilumab, mepolizumab, benralizumab and omalizumab. The choice of medication depends on the individual patient context, which includes the presence of atopic dermatitis, eosinophilia, or asthma.

Innate lymphoid cells (ILC) are a heterogeneous group of immune cells characterized by lymphoid morphology and cytokine profile similar to T cells but which do not express clonally distributed diverse antigen receptors. These particular cells express transcription factors and cytokines reflecting their similarities to T helper (Th)1, Th2, and Th17 cells and are therefore referred to as ILC1, ILC2, and ILC3. Other members of the ILC subsets include lymphoid tissue inducer (LTi) and regulatory ILC (ILCreg). Natural killer (NK) cells share a common progenitor with ILC and also exhibit a lymphoid phenotype without antigen specificity. ILC are found in low numbers in peripheral blood but are much more abundant at barrier sites such as the skin, liver, airways, lymph nodes, and the gastrointestinal tract. They play an important role in innate immunity due to their capacity to respond rapidly to pathogens through the production of cytokines. Recent evidence has shown that ILC also play a key role in autoimmunity, as alterations in their number or function have been identified in systemic lupus erythematosus, systemic sclerosis, and rheumatoid arthritis. Here, we review recent advances in the understanding of the role of ILC in the pathogenesis of autoimmune diseases, with particular emphasis on their role as a potential diagnostic biomarker and as therapeutic targets.

Patient suffering from autoimmune diseases (AID) typically have an increased risk of infection, which is attributed to the disease itself, but also to immunosuppressive drugs (IS) and comorbidities. During the current COVID-19 outbreak, the way to manage these diseases remains elusive. Limited data is currently available on AID and IS in the context of this new coronavirus infection. To date, there is no evidence to support an increase in complications of COVID-19 in these patients. In addition, certain drugs that are commonly used to treat AID could be part of the therapeutic arsenal used in COVID-19. The purpose of this article is to review the unique aspects of patients with AID during the COVID-19 outbreak.

Fag.H.3.44 no.38, ‘Antwoort van een getrouwe Hollander, op het memoriael, door den heere grave d’Avaux...’ was printed in 1684, during the time that Gaspar Fagel was Grand Pensionary of Holland. The Fagel collection during this time resembles what we can call Hendrik Fagel’s working papers: short, anonymous pamphlets containing official memoranda, speeches, resolutions, and ordinances, passing through Fagel’s hands in the offices of state, of which this is one. Fag.H.3.44 no.38 is an anonymous response to one of the latest memos of the French ambassador. The “getrouwe Hollander ” (loyal Hollander) urges Dutch support for Spain and accuses the French of stalling negotiations while strengthening their military position in the Southern Netherlands. It captures the essence of a new age of pamphleteering and diplomacy, so carefully laid out in the Fagel Collection. Fag.H.3.44 no.38 is bound together in a volume containing 96 other individual texts, all printed in 1684. These are largely composed of speeches and memoranda by the Spanish and French ambassadors in The Hague, during the War of the Reunions (1683-1684), which saw French forces overrun Spanish possessions in the Low Countries.

The present dataset is a high-resolution earthquake catalog for the region of the 2014 M8.1 Iquique earthquake sequence, in the Northern Chile subduction zone. Events in the catalog were obtained processing seismic waveforms from >100 permanent and temporary seismic stations. The list of waveform data sources used, the multistage automatic earthquake detection and location procedure implemented to build the catalog, as well as the patterns outlined by the seismicity are described in Soto et al. (2019).

Understanding the processes behind subduction-related hazards is an important responsibility and major challenge for the Earth sciences. Few areas demonstrate this as clearly as south-central Chile, where some of the largest earthquakes in human history have occurred. We present the first observation of local seismicity in the Villarrica region (39-40S), based on a temporary local network of 55 stations installed from the Chilean coast into the Argentinian back-arc for one year. While consistent with the Chilean national catalog (SSN), our results allow us to observe smaller magnitudes with a completeness of about 2.0 and image the geometry of the Wadati-Benioff Zone from the Chile Trench down to 200 km. Offshore, a gap in interplate seismicity is observed in the region of the 1960 Valdivia earthquake slip. Above the interface, two offshore seismicity clusters possibly indicate ongoing stress relaxation. In the subducting Nazca Plate, we find a prominent seismicity cluster along the extrapolated trace of the oceanic Valdivia Fracture Zone (VFZ). The seismicity cluster is observed between 70 and 130 km depth and comprises mainly strike-slip events. It indicates weakening and reactivation of the major VFZ by dehydration of oceanic crust and mantle. Interpreting the subducted VFZ section as a localized reservoir of potential fluid release offers an explanation for the Villarrica volcanic complex that is located above the reactivated VFZ and shows the highest volcanic activity in South America. Crustal seismicity is observed near Puyehue volcano, which recently started to erupt (June 2011). Fil: Dzierma, Yvonne. Christian-Albrechts University Kie; Alemania Fil: Thorwart, Martin. Christian-Albrechts University Kie; Alemania Fil: Rabbel, Wolfgang. Christian-Albrechts University Kie; Alemania Fil: Siegmund, Claudia. Christian-Albrechts University Kie; Alemania Fil: Comte, Diana. Universidad de Chile; Chile Fil: Bataille, Klaus. Universidad de Concepción; Chile Fil: Iglesia Llanos, Maria Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; Argentina Fil: Prezzi, Claudia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; Argentina

International audience; The 27 February 2010 Maule, Chile (Mw=8.8) earthquake is one of the best instrumentally observed subduction zone megathrust events. Here we present locations, magnitudes and cumulative equivalent moment of the first $2 months of aftershocks, recorded on a temporary network deployed within 2 weeks of the occurrence of the main-shock. Using automatically-determined onset times and a back projection approach for event association, we are able to detect over 30,000 events in the time period analyzed. To further increase the location accuracy, we systematically searched for potential S-wave arrivals and events were located in a regional 2D velocity model. Additionally, we calculated regional moment tensors to gain insight into the deformation history of the aftershock sequence. We find that the aftershock seismicity is concentrated between 40 and 140 km distance from the trench over a depth range of 10 to 35 km. Focal mechanisms indicate a predominance of thrust faulting, with occasional normal faulting events. Increased activity is seen in the outer-rise region of the Nazca plate, predominantly in the northern part of the rupture area. Further down-dip, a second band of clustered seismicity, showing mainly thrust motion, is located at depths of 40-45 km. By comparing recent published mainshock source inversions with our aftershock distribution, we discriminate slip models based on the assumption that aftershocks occur in areas of rapid transition between high and low slip, surrounding high-slip regions of the mainshock.

On 27 February 2010 theMw 8.8 Maule earthquake in Central Chile ruptured a well known seismic gap, which last broke in 1835. Shortly after the mainshock, Chilean agencies (UC Santiago, UC Concepción) and the international seismological community (USA (IRIS), France (IPGP), UK (University of Liverpool), Germany (GFZ)) installed a total of 142 portable seismic stations along the whole rupture zone in order to capture the aftershock activity. Most stations were in the field until September 2010, with a subset remaining until January 2011; the UK stations will remain in the field beyond this time. The data from the initial deployment are open and are being distributed through the IRIS and GEOFON data centres. We will present preliminary aftershock distributions based on automatic detection algorithms. In total, for the period between March and September 2010 we detected _60,000 locatable earthquakes, of which we form a subset of _7,000 events with high quality locations. The depth of events in the high quality subset is generally well constrained such that the plate interface is clearly defined, and can be separated from overriding plate seismicity. First order features that can be identified are: 1.) A pronounced cluster of seismicity is apparent at 25-35 km depth and 50-120 km perpendicular distance from the trench (with some NS variation). 2.) A secondary band of seismicity can be identified at 40-50 km depth and _150-160 km perpendicular trench distance and between 34_ and 37_S. Although the secondary band lies along the continuation of the primary one, it is clearly separated from it by a gap with sparse seismicity. 3.) Intense crustal seismicity is found in the region of Pichilemu. This region hosted the strongest aftershock (Mw=6.9), a normal faulting event with NW strike. The aftershocks extend from the plate interface to the surface and are aligned on a NNW-SSE oriented band in map view. 4.) An isolated shallow cluster of crustal seismicity occurs beneath the volcanic arc (36.42_S, 71.1_W) near Laguna del Dial. Ongoing research is concerned with calculating first motion focal mechanisms for the larger events and improving locations by relative location methods.