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CO 2 capture and storage in geological reservoirs have the potential to significantly mitigate the effects of anthropogenic gas emissions on global climate. Here, we report the results of the first laboratory experiments of CO 2 injection in continental flood basalts of South America. The results show that the analyzed basalts have a mineral assemblage, texture and composition that efficiently allows a fast carbonate precipitation that starts 72 h after injection. Based on the availability of calcium, chemical monitoring indicates an estimated CO 2 storage of ~ 75%. The carbonate precipitation led to the precipitation of aragonite (75.9%), dolomite (19.6%), and calcite (4.6%)., (© 2024. The Author(s).)

Introduction: Common variable immunodeficiency (CVID) comprises a heterogeneous group of disorders characterized by impaired antibody production. Kidney involvement in CVID is described in isolated and sporadic case reports. The objective of this study was to study the renal function pattern in CVID patients through glomerular and tubular function tests., Methods: Study of 12 patients with CVID diagnosis and 12 healthy control individuals. Glomerular filtration rate (GFR), fractional excretion of sodium (FE Na + ) and potassium (FE K + ), urinary concentration, and acidification capacity were measured. In addition, microalbuminuria and urinary monocyte chemoattractant protein-1 (MCP-1) were evaluated as markers of selectivity of the glomerular barrier and inflammation, respectively., Results: In relation to glomerular markers, all CVID patients had normal GFR (>90 mL/min/1.73 m 2 ), and microalbuminuria and urinary MCP-1 levels were also similar to those of controls. Interestingly, CVID patients had reduced urinary concentration capacity, as demonstrated by lower U / P Osm ratio, when compared to controls. Also, while all control subjects achieved a urinary pH less than 5.3, no CVID patients showed a decrease in urinary pH to such levels in response to acid loading with CaCl 2 , characterizing impaired urinary acidification capacity., Conclusion: Patients showed a trend towards an elevated prevalence of tubular dysfunction, mainly related to urinary acidification and concentration capacities.

A lectin was purified from the cotyledons of Luetzelburgia auriculata (Fr. All) Ducke by affinity chromatography on agarose-N-acetyl-D-galactosamine. The lectin is a potent agglutinin for rabbit erythrocytes, reacts with human red cells, but is inactive against cow, sheep, and goat erythrocytes. Hemagglutination of rabbit erythrocytes was inhibited by either 0.39 mM N-acetyl-neuraminic acid or N-acetyl-D-galactosamin, 12.5 mM D-lactose or D-melibiose, 50 mM D-galactose or raffinose. Its hemagglutinating activity was lost at 80 degrees C, 5 min, and the activation energy required for denaturation was 104.75 kJ mol(-1). Chromatography on Sephadex G-100, at pH 7.6, showed that at this hydrogenic ionic concentration the native lectin was a homotetramer (123.5 kDa). By denaturing SDS-PAGE, LAA seemed to be composed of a mixture of 29 and 15 kDa polypeptide subunits. At acidic and basic pHs it assumed different conformations, as demonstrated by exclusion chromatography on Superdex 200 HR 10/30. The N-terminal sequence of the 29 kDa band was SEVVSFSFTKFNPNQKDII and the 15 kDa band contained a mixture of SEVVSFSFTKFNPNQKDII and KFNQIVAVEEDTDXESQPQ sequences, indicating that these bands may represent full-length and its endogenous fragments, respectively. The lectin is a glycoprotein having 3.2% neutral carbohydrate, with a pI of 5.8, containing high levels of Asp+Asn and Glu+Gln and hydroxy amino acids, and low amount or absence of sulfur amino acids. Its absorption spectrum showed a maximum at 280 nm and a epsilon (1%) x (1cm) of 5.2. Its CD spectrum was characterized by minima near 228 nm, maxima near 196 nm and a negative to positive crossover at 210 nm. The secondary structure content was 6% alpha-helix, 8% parallel beta-sheet, 38% antiparallel beta-sheet, 17% beta-turn, 31% unordered and others contribution, and 1% RMS (root mean square). In the fluorescence spectroscopy, excitation of the lectin solution at 280 nm gave an emission spectrum in the 285-445 nm range. The wavelength maximum emission was in 334.5 nm, typical for tryptophan residues buried inside the protein.