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Hydrothermal processes that lead to REE fractionation and redistribution are important for understanding water-rock interactions in geothermal energy resources and mineral deposits, and for determining how submarine hydrothermal activity affects the composition of oceanic crust. Much previous work on REE transport and deposition has focused on submarine hydrothermal vents. We report REE concentrations in boiled fluids sampled from five subaerial, basalt-hosted geothermal fields, and explore controls on aqueous REE concentrations by ligand complexation and mineral supersaturation. Samples that boiled at pressures between 0.8 and 2.83 MPa were obtained from the Reykjanes, Svartsengi, Hellisheidi, and Nesjavellir geothermal systems in Iceland, and the Puna geothermal system in Hawaii. For comparison, we also report REE concentrations in hydrothermal fluids from the sediment hosted submarine Middle Valley hydrothermal system, which boiled at >250 MPa. The pH(25°C) values of the sampled subaerial geothermal fluids range from 3.94 to 6.77, and Cl concentrations range from near seawater (502 mmol/kg) to dilute (1.9 mmol/kg). La, Ce and Eu are the only REE present at levels above 5 picomole/kg (pmol/kg) in the boiled geothermal fluids; and there are notable CI chondrite normalized La and Eu anomalies in the saline fluids. REE concentrations in Middle Valley hydrothermal fluids fall within the typical range reported for submarine hydrothermal fluids and have around two orders of magnitude higher REE than the boiled subaerial geothermal fluids. Bulk samples of precipitates in pipes from the Reykjanes geothermal system have detectable REE, confirming that downhole fluids have lost REE during boiling and production of fluids for geothermal energy. Isenthalpic boiling models show that the proportions of La and Eu chloride complexes increase relative to other aqueous species as boiling progresses, attenuating the incorporation of La and Eu into precipitated well scale solids. Fluorapatite is calculated to precipitate on boiling of low pH and saline fluids and calcite is calculated to precipitate from dilute and near-neutral pH fluids, and these minerals likely sequester REE in boiled subaerial fluids. Submarine hydrothermal fluids are constrained to boiling at higher temperatures than subaerial geothermal fluids owing to pressure from overlying cold seawater, therefore secondary minerals and solids that incorporate REE are not extensively precipitated and REE concentrations in the fluids are higher.

Background Viral infection outcomes vary widely between individuals, ranging from mild symptoms to severe organ failure and death, and it is clear that host genetic factors play a role in this variability. Type I interferon (IFN) is a critical anti-viral cytokine, and we have previously noted differences in type I IFN levels between world populations. Methods In this study, we investigate the interrelationship between regional European genetic ancestry, type I IFN levels and severe viral infection outcomes. Results In cohorts of European ancestry lupus patients living in Europe, we noted higher IFN in the Northwestern populations as compared to Southeastern populations. In an independent cohort of European ancestry lupus patients from the USA with varying proportional regional European genetic admixture, we observed the same Northwest vs. Southeast European ancestry IFN gradient. We developed a model to predict type I IFN level based on regional European ancestry (Area under the curve (AUC) = 0.73, P  = 6.1e-6). Examining large databases containing serious viral outcomes data, we found that lower predicted IFN in the corresponding European country was significantly correlated with increased viral infection fatality rate, including Coronavirus Disease 2019 (COVID-19), viral hepatitis and HIV [correlation coefficients: −0.79 (P  = 4e-2), −0.94 (P  = 6e-3) and −0.96 (P  = 8e-2), respectively]. Conclusions This association between predicted type I IFN level and viral outcome severity suggests a potential causal relationship, as greater intrinsic type I IFN is beneficial in host defense against viruses. Genetic testing could provide insight into individual and population level risk of fatality due to viruses prior to infection, across a wide range of viral pathogens. [ABSTRACT FROM AUTHOR]

Recent genome-wide association studies (GWASs) conducted in Asian populations have identified novel risk loci for systemic lupus erythematosus (SLE). Here, we genotyped 10 single-nucleotide polymorphisms (SNPs) in eight such loci and investigated their dis

Patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) require immunosuppressive therapy for disease control and relapse prevention and may be at risk for severe coronavirus disease 2019 (COVID-19). The study objective was to analyse risk factors and outcomes of COVID-19 in well-characterized AAV patients. Data were retrieved from March 2020 to May 2021 from medical records of AAV cohorts in Stockholm and Uppsala, Sweden. COVID-19 was confirmed by positive PCR test or by ELISA. Severe COVID-19 was defined as need for non-invasive ventilation, intensive care unit care, and/or death. Age, gender, ANCA antibody type, ongoing immunosuppressive medication, and estimated glomerular filtration rate were recorded. The cohort comprised 310 AAV patients, of whom 29 (9%) were diagnosed with COVID-19. Four deaths were attributed to COVID-19. Fifteen patients (52%) were on prednisolone in the COVID-19 group and 130 (46%) in the non-COVID group, with significantly higher doses in COVID-19 patients (p < 0.01). Ongoing induction therapy was more prevalent in the COVID-19 group (p < 0.01). Severe COVID-19 was diagnosed in 9/29 (31%). Significant risk factors for severe COVID-19 were impaired kidney function (p = 0.01) and more intense immunosuppressive therapy (p = 0.02), with a trend for age (p = 0.07). Maintenance therapy with rituximab was not associated with severe COVID-19. Our findings highlight risks and suggest that more attention should be given to optimal AAV treatment in a pandemic situation. They also emphasize the need for continued shielding, mitigation strategies, and effective vaccination of AAV patients. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate pentraxin-3 (PTX3) as a potential biomarker of inflammatory activity in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) at baseline and 6 month follow-up in a longitudinal cohort. Plasma PTX3 levels were measured in 79 newly diagnosed or relapsing AAV patients at baseline and 6 month follow-up, and in 23 healthy controls. Urinary PTX3 levels were measured in 34 of the patients. C-reactive protein (CRP), creatinine, and albuminuria were measured and the cumulative glucocorticoid dose at inclusion was calculated. The Birmingham Vasculitis Activity Score (BVAS) was assessed at baseline and follow-up. Plasma PTX3 levels were significantly higher at baseline than at 6 months (2.85 vs 1.23 ng/mL, p < 0.001). Plasma and urinary PTX3 levels correlated with BVAS at baseline (ρ = 0.45, p < 0.001, and ρ = 0.49, p = 0.008, respectively). A significant correlation between both plasma and urinary PTX3 levels and estimated glomerular filtration rate and albuminuria was found. However, there was no correlation between plasma and urinary PTX3 levels. At baseline, plasma and urinary PTX3 levels were significantly higher in patients with kidney involvement. PTX3 levels did not correlate with CRP, nor was there a correlation between CRP levels and BVAS at baseline. Plasma and urinary PTX3 seem to reflect disease activity in AAV better than the commonly used CRP. PTX3 may have a potential role as a biomarker in monitoring disease activity in AAV patients, particularly in patients with kidney involvement. [ABSTRACT FROM AUTHOR]