The solubility of Zr(OH)4(am)--in other words hydrated Zr(IV) oxyhydroxide--is determined by means of coulometric titration (CT), and colloids are detected by laser-induced breakdown when the solubility limit is exceeded. Our results at pH 3-8 demonstrate that the solubility of Zr(OH)4(am) is several orders of magnitude higher than reported classical solubility data for acidic solutions, determined from undersaturation with a less soluble microcrystalline Zr(IV) oxide precipitate. Analysis of extended X-ray absorption fine structure (EXAFS) data shows that the microcrystalline colloids in a 0.1 mol l(-1) Zr aqueous solution at pH 0.2 contain tetrameric units, similar to those present in the structure of ZrOCl2.8H2O. Characterization of the CT solutions by means of EXAFS shows that oligomeric species form as the solubility limit is approached. The current lack of data on equilibrium constants for polynuclear hydroxide complexes prohibits the use of a realistic speciation model to describe the solubility of pH-dependent Zr(OH)4(am). However, the solubility curve is obtained using the mononuclear hydrolysis constants estimated in the present paper, along with the solubility constant (log K'sp=-49.9+/-0.5 in 0.5 mol l(-1) NaCl; log K degrees(sp)=-53.1+/-0.5 at I=0).
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Front Immunol
December 2024
Department of Medicine, Division of Hematology, Oncology and Transplantation, University of Minnesota, Minneapolis, MN, United States.
Sickle cell disease (SCD) is a devastating hemolytic disease, marked by recurring bouts of painful vaso-occlusion, leading to tissue damage from ischemia/reperfusion pathophysiology. Central to this process are oxidative stress, endothelial cell activation, inflammation, and vascular dysfunction. The endothelium exhibits a pro-inflammatory, pro-coagulant, and enhanced permeability phenotype.
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December 2024
Tumor Vaccine and Biotechnology Branch, Office of Cellular Therapy and Human Tissues, Office of Therapeutic Products, Center for Biologics Evaluation and Research, United States Food and Drug Administration (U.S. FDA), Silver Spring, MD, United States.
Introduction: CAR-T cell therapy is associated with life-threatening inflammatory toxicities, partly due to the activation and secretion of inflammatory cytokines by bystander myeloid cells (BMCs). However, due to limited clinical data, it is unclear whether CAR-NK cells cause similar toxicities.
Methods: We characterized the soluble factors (SFs) released by activated human CAR-T and CAR-NK cells and assessed their role in BMC activation (BMCA).
Theranostics
January 2025
Department of Infectious Diseases, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, China.
Acute liver failure (ALF) is marked by a substantial generation of reactive oxygen species (ROS), which can induce both cellular senescence and a pronounced inflammatory response. Senescent cells secrete factors collectively termed the senescence-associated secretory phenotype (SASP), which exacerbate inflammation, while inflammation can reciprocally promote cellular senescence. Quercetin (Que), recognized for its ROS-scavenging capabilities, holds the potential for anti-inflammatory and anti-senescent effects.
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December 2024
School of Basic Medical Sciences, Zhejiang Chinese Medical University, Hangzhou, China.
Background: Salvianolic acid B (Sal B) is potentially the most valuable water-soluble active component in Salvia miltiorrhiza. Its chemical formula contains multiple phenolic hydroxyl groups, so it has a strong antioxidant capacity.
Objective: We aim to investigate the efficacy and the potential mechanism of Sal B in the treatment of acute ischemic stroke injury.
Int J Nanomedicine
January 2025
Department of pharmacy, west china hospital, Sichuan University, Chengdu, 610041, People's Republic of China.
Amphiphilic copolymers are composed of both hydrophilic and hydrophobic chains, which can self-assemble into polymeric micelles in aqueous solution via the hydrophilic/hydrophobic interactions. Due to their unique properties, polymeric micelles have been widely used as drug carriers. Poorly soluble drugs can be covalently attached to polymer chains or non-covalently incorporated in the micelles, with improved pharmacokinetic profiles and enhanced efficacy.
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