Lanthanum-fluoride electrode-based methods to monitor fluoride transport in cells and reconstituted lipid vesicles.

Fluoride (F-) export proteins, including F- channels and F- transporters, are widespread in biology. They contribute to cellular resistance against fluoride ion, which has relevance as an ancient xenobiotic, and in more modern contexts like organofluorine biosynthesis and degradation or dental medicine. This chapter summarizes quantitative methods to measure fluoride transport across membranes using fluoride-specific lanthanum-fluoride electrodes. Electrode-based measurements can be used to measure unitary fluoride transport rates by membrane proteins that have been purified and reconstituted into lipid vesicles, or to monitor fluoride efflux into living microbial cells. Thus, fluoride electrode-based measurements yield quantitative mechanistic insight into one of the major determinants of fluoride resistance in microorganisms, fungi, yeasts, and plants.

Nano La(OH)3 modified lotus seedpod biochar: A novel solution for effective phosphorus removal from wastewater.

Effective removal of phosphorus from water is crucial for controlling eutrophication. Meanwhile, the post-disposal of wetland plants is also an urgent problem that needs to be solved. In this study, seedpods of the common wetland plant lotus were used as a new raw material to prepare biochar, which were further modified by loading nano La(OH)3 particles (LBC-La). The adsorption performance of the modified biochar for phosphate was evaluated through batch adsorption and column adsorption experiments. Adsorption performance of lotus seedpod biochar was significantly improved by La(OH)3 modification, with adsorption equilibrium time shortened from 24 to 4 h and a theoretical maximum adsorption capacity increased from 19.43 to 52.23 mg/g. Moreover, LBC-La maintained a removal rate above 99% for phosphate solutions with concentrations below 20 mg/L. The LBC-La exhibited strong anti-interference ability in pH (3-9) and coexisting ion experiments, with the removal ratio remaining above 99%. The characterization analysis indicated that the main mechanism is the formation of monodentate or bidentate lanthanum phosphate complexes through inner sphere complexation. Electrostatic adsorption and ligand exchange are also the mechanisms of LBC-La adsorption of phosphate. In the dynamic adsorption experiment of simulated wastewater treatment plant effluent, the breakthrough point of the adsorption column was 1620 min, reaching exhaustion point at 6480 min, with a theoretical phosphorus saturation adsorption capacity of 6050 mg/kg. The process was well described by the Thomas and Yoon-Nelson models, which indicated that this is a surface adsorption process, without the internal participation of the adsorbent.

Rare Earth Extraction from Phosphogypsum by Aspergillus niger Culture Broth.

The extraction of rare earth elements (REEs) from phosphogypsum (PG) is of great significance for the effective utilization of rare earth resources and enhancing the resource value of PG waste residues. This study used Aspergillus niger (A. niger) fungal culture filtrate as a leaching agent to investigate the behavior of extracting REEs from PG through direct and indirect contact methods. According to the ICP-MS results, direct leaching at a temperature of 30 °C, shaking speed of 150 rpm, and a solid-liquid ratio of 2:1, achieved an extraction rate of 74% for REEs, with the main elements being yttrium (Y), lanthanum (La), cerium (Ce), and neodymium (Nd). Under the same conditions, the extraction rate of REEs from phosphogypsum using an A. niger culture filtrate was 63.3% higher than that using the simulated organic acid-mixed solution prepared with the main organic acid components in the A. niger leachate. Moreover, the morphological changes observed in A. niger before and after leaching further suggest the direct involvement of A. niger's metabolic process in the extraction of REEs. When compared to using organic acids, A. niger culture filtrate exhibits higher leaching efficiency for extracting REEs from PG. Additionally, using A. niger culture filtrate is a more environmentally friendly method with the potential for industrial-scale applications than using inorganic acids for the leaching of REEs from PG.

Lanthanum hydroxide protects kidney through gut microbiota in a rat model of chronic kidney disease.

The progression of chronic kidney diseases (CKD) is complex, influenced by a myriad of factors including gut microbiota. While emerging evidence suggests that gut microbiota can have beneficial effects in managing CKD, it is also recognized that dysbiosis may contribute to the progression of CKD and associated uremic complications. Our previous research has demonstrated the efficacy of lanthanum hydroxide in delaying kidney failure and preserving renal function. However, the role of lanthanum hydroxide in modulating gut microbiota in this context remains unclear. In our study, we induced CKD in rats using adenine, leading to gut microbial dysbiosis, kidney pathology, and disturbances in amino acid metabolism. In this adenine-induced CKD model with hyperphosphatemia, treatment with lanthanum hydroxide improved renal function. This improvement was associated with the restoration of gut microbial balance and an increase in urine ammonium metabolism. These results suggest that the therapeutic potential of lanthanum hydroxide in CKD may be partly due to its ability to reshape gut microbiota composition. This study underscores the significance of lanthanum hydroxide in kidney protection, attributing its benefits to the modulation of gut microbiota in a rat model of CKD.

Rare earth contamination of edible vegetation: Ce, La, and summed REE in fungi.

The increasing and diversified use of rare earth elements (REE) is considered a potential source of pollution of environmental media including soils. This work documents critically overview data on the occurrence of REE in the fruiting bodies of wild and farmed species of edible and medicinal mushrooms, as this was identified as the largest published dataset of REE occurrence in foodstuff. Most of the literature reported occurrences of cerium (Ce) and lanthanum (La), but a number of studies lacked data on all lanthanides. The Ce, La, and summed REE occurrences were assessed through the criteria of environmental geochemistry, analytical chemistry, food toxicology, mushroom systematics, and ecology. Ce and La accumulate similarly in fruiting bodies and are not fractionated during uptake, maintaining the occurrence patterns of their growing substrates. Similarly, there is no credible evidence of variable REE uptake because the evaluated species data show natural, unfractionated patterns in accordance with the Oddo-Harkins' order of environmental lanthanide occurrence. Thus, lithosphere occurrence patterns of Ce and La as the first and the third most abundant lanthanides are reflected in wild and farmed mushrooms regardless of substrate and show that Ce is around twice more abundant than La. The current state of knowledge provides no evidence that mushroom consumption at these REE occurrence levels poses a health risk either by themselves or when included with other dietary exposure. Macromycetes appear to bio-exclude lanthanides because independently reported bioconcentration factors for different species and collection sites, typically range from < 1 to 0.001. This is reflected in fruiting body concentrations which are four to two orders of magnitude lower than growing substrates. KEY POINTS: •Original REE occurrence patterns in soils/substrates are reflected in mushrooms •No evidence for the fractionation of REE during uptake by fungi •Mushrooms bio-exclude REE in fruiting bodies.

La2O3 Nanoparticles Can Cause Cracking of Tomato Fruit through Genetic Reconstruction.

La2O3 nanoparticles (NPs) have shown great potential in agriculture, but cracking of plant sensitive tissue could occur during application, resulting in a poor appearance, facilitating entry for insects and fungi, and increasing economic losses. Herein, exocarp cracking mechanisms of tomato (Solanum lycopersicum L.) fruit in response to La2O3 NPs were investigated. Tomato plants were exposed to La2O3 NPs (0-40 mg/L, 90 days) by a split-root system under greenhouse condition. La2O3 NPs with high concentrations (25 and 40 mg/L) increased the obvious cracking of the fruit exocarp by 20.0 and 22.7%, respectively. After exposure to 25 mg/L La2O3 NPs, decreased thickness of the cuticle and cell wall and lower wax crystallization patterns of tomato fruit exocarp were observed. Biomechanical properties (e.g., firmness and stiffness) of fruit exocarp were decreased by 34.7 and 25.9%, respectively. RNA-sequencing revealed that the thinner cuticle was caused by the downregulation of cuticle biosynthesis related genes; pectin remodeling, including the reduction in homogalacturonan (e.g., LOC101264880) and rhamnose (e.g., LOC101248505), was responsible for the thinner cell wall. Additionally, genes related to water and abscisic acid homeostasis were significantly upregulated, causing the increases of water and soluble solid content of fruit and elevated fruit inner pressure. Therefore, the thinner fruit cuticle and cell wall combined with the higher inner pressure caused fruit cracking. This study improves our understanding of nanomaterials on important agricultural crops, including the structural reconstruction of fruit exocarp contributing to NPs-induced cracking at the molecular level.

Construction of p-n-p nano heterojunction through coupling La2O3, (BiO)2CO3 and Ag3PO4 for effective photocatalytic degradation of doxycycline: Insights into mechanism, pathway and intermediate toxicity evaluation.

The present work is centred around the development of La2O3/(BiO)2CO3/Ag3PO4 (LBA), a p-n-p nano-heterojunction to photodegrade doxycycline under visible light irradiation. Here, ultrasonication assisted co-precipitation method was employed to synthesize the photocatalyst. The photocatalyst was characterized using different analysis such as SEM, TEM, elemental mapping, XRD, XPS, FTIR, Raman, BET, DRS, PL and EIS which confirmed the successful fabrication of LBA and their excellent ability to refrain the e-/h+ recombination owing to the construction of the heterojunction. LBA was found to degrade DOX by 91.75 % with the high mineralization of 87.23%. The impact of the reaction parameters influencing the photodegradation process including the concentration of the NCs and DOX, pH and the influence of the commonly present anions were studied. The stability and reusability of the LBA was assessed through subjecting it to four cycles of photodegradation of DOX. In addition, the recovered LBA was characterized through XPS and XRD analysis to confirm the particles stability and reusability. The active participation of the photogenerated charges and the reactive oxygen species were identified through the scavenging assay and ESR analysis. Further, GC-MS/MS analysis was performed to put forward a plausible photodegradation pathway. The toxicity of the end products as well as the intermediates was predicted through ECOSAR software.

Rare earth elements perturb root architecture and ion homeostasis in Arabidopsis thaliana.

Rare earth elements (REEs) are crucial elements for current high-technology and renewable energy advances. In addition to their increasing usage and their low recyclability leading to their release into the environment, REEs are also used as crop fertilizers. However, little is known regarding the cellular and molecular effects of REEs in plants, which is crucial for better risk assessment, crop safety and phytoremediation. Here, we analysed the ionome and transcriptomic response of Arabidopsis thaliana exposed to a light (lanthanum, La) and a heavy (ytterbium, Yb) REE. At the transcriptome level, we observed the contribution of ROS and auxin redistribution to the modified root architecture following REE exposure. We found indications for the perturbation of Fe homeostasis by REEs in both roots and leaves of Arabidopsis suggesting competition between REEs and Fe. Furthermore, we propose putative ways of entry of REEs inside cells through transporters of microelements. Finally, similar to REE accumulating species, organic acid homeostasis (e.g. malate and citrate) appears critical as a tolerance mechanism in response to REEs. By combining ionomics and transcriptomics, we elucidated essential patterns of REE uptake and toxicity response of Arabidopsis and provide new hypotheses for a better evaluation of the impact of REEs on plant homeostasis.

The combined effects of lanthanum-modified bentonite and Vallisneria spiralis on phosphorus, dissolved organic matter, and heavy metal(loid)s.

The use of lanthanum-modified bentonite (LMB) combined with Vallisneria spiralis (V∙s) (LMB + V∙s) is a common method for controlling internal phosphorus (P) release from sediments. However, the behaviors of iron (Fe) and manganese (Mn) under LMB + V∙s treatments, as well as the associated coupling effect on P, dissolved organic matter (DOM), and heavy metal(loid)s (HMs), require further investigations. Therefore, we used in this study a microelectrode system and high-resolution dialysis technology (HR-Peeper) to study the combined effects of LMB and V∙s on P, DOM, and HMs through a 66-day incubation experiment. The LMB + V∙s treatment increased the sediment DO concentration, promoting in-situ formations of Fe (III)/Mn (IV) oxyhydroxides, which, in turn, adsorbed P, soluble tungsten (W), DOM, and HMs. The increase in the concentrations of HCl-P, amorphous and poorly crystalline (oxyhydr) oxides-bound W, and oxidizable HMs forms demonstrated the capacity of the LMB + V∙s treatment to transform mobile P, W, and other HMs forms into more stable forms. The significant positive correlations between SRP, soluble W, UV254, and soluble Fe (II)/Mn, and the increased concentrations of the oxidizable HMs forms suggested the crucial role of the Fe/Mn redox in controlling the release of SRP, DOM, and HMs from sediments. The LMB + V∙s treatment resulted in SRP, W, and DOM removal rates of 74.49, 78.58, and 54.78 %, which were higher than those observed in the control group (without LMB and V∙s applications). On the other hand, the single and combined uses of LMB and V·s influenced the relative abundances of the sediment microbial communities without exhibiting effects on microbial diversity. This study demonstrated the key role of combined LMB and V∙s applications in controlling the release of P, W, DOM, and HMs in eutrophic lakes.

Weathered granites and soils harbour microbes with lanthanide-dependent methylotrophic enzymes.

BACKGROUND: Prior to soil formation, phosphate liberated by rock weathering is often sequestered into highly insoluble lanthanide phosphate minerals. Dissolution of these minerals releases phosphate and lanthanides to the biosphere. Currently, the microorganisms involved in phosphate mineral dissolution and the role of lanthanides in microbial metabolism are poorly understood. RESULTS: Although there have been many studies of soil microbiology, very little research has investigated microbiomes of weathered rock. Here, we sampled weathered granite and associated soil to identify the zones of lanthanide phosphate mineral solubilisation and genomically define the organisms implicated in lanthanide utilisation. We reconstructed 136 genomes from 11 bacterial phyla and found that gene clusters implicated in lanthanide-based metabolism of methanol (primarily xoxF3 and xoxF5) are surprisingly common in microbial communities in moderately weathered granite. Notably, xoxF3 systems were found in Verrucomicrobia for the first time, and in Acidobacteria, Gemmatimonadetes and Alphaproteobacteria. The xoxF-containing gene clusters are shared by diverse Acidobacteria and Gemmatimonadetes, and include conserved hypothetical proteins and transporters not associated with the few well studied xoxF systems. Given that siderophore-like molecules that strongly bind lanthanides may be required to solubilise lanthanide phosphates, it is notable that candidate metallophore biosynthesis systems were most prevalent in bacteria in moderately weathered rock, especially in Acidobacteria with lanthanide-based systems. CONCLUSIONS: Phosphate mineral dissolution, putative metallophore production and lanthanide utilisation by enzymes involved in methanol oxidation linked to carbonic acid production co-occur in the zone of moderate granite weathering. In combination, these microbial processes likely accelerate the conversion of granitic rock to soil.

Determination of dose- and time-dependent hepatotoxicity and apoptosis of Lanthanum oxide nanoparticles in female Swiss albino mice.

Nanosized lanthanum oxide particles (La2O3) are commonly utilized in various industries. The potential health risks associated with La2O3 nanoparticles, cytotoxic effects at varying doses and time intervals, and the mechanisms behind their induction of behavioral changes remain uncertain and necessitate further investigation. Therefore, this study examined in vivo hepatotoxicity, considering the quantity (60, 150, and 300 mg/kg) and time-dependent induction of reactive oxygen species (ROS) over one week or 21 days. The mice received intraperitoneal injections of three different concentrations in Milli-Q water. Throughout the experiments, no physical changes or weight loss were observed among the groups. However, after 21 days, only the highest concentration showed signs of anxiety in the activity cage (p < 0.05). Subsequently, all animals treated with La2O3 NPs exhibited a significant loss of learning and memory recall using the Active Avoidances test, after 21 days (p < 0.001). Markers for anti-reactive oxygen species (ROS) such as superoxide dismutase (SOD) were significantly upregulated in response to all concentrations of NPs after seven days compared to the control group. This was confirmed by a significant increase in glutathione peroxidase (Gpx1) and pro-apoptotic Caspase-3 expression at the lowest and highest doses. Additionally, both transcription and protein levels of the anti-apoptotic BCL-2 surpassed P53 protein in a dosage-dependent manner, indicating activation of the primary anti-apoptosis pathway. After 21 days, P53 levels exceeded BCL-2 protein levels, confirming a significant loss of BCL-2 mRNA, particularly at the 300 mg/kg concentration. Furthermore, a higher transcription level of Caspase-3, SOD, and Gpx1 was observed, with the highest values detected at the 300 mg/kg concentration, indicating the activation of cell death. Histopathological analysis of the liver illustrated apoptotic bodies resulting from La2O3 NP concentration. The investigation revealed multiple inflammatory foci, cytoplasmic degeneration, steatosis, and DNA fragmentation consistent with increased damage over time due to higher concentrations. Blood samples were also analyzed to determine liver enzymatic changes, including alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate aminotransferase (AST), and lipid profiles. The results showed significant differences among all La2O3 NP concentrations, with the most pronounced damage observed at the 300 mg/kg dose even after 21 days. Based on an animal model, this study suggests that La2O3 hepatotoxicity is likely caused by the size and shape of nanoparticles (NPs), following a dose and time-dependent mechanism that induces the production of reactive oxygen species and behavioral changes such as anxiety and memory loss.

The effects of different doses of lanthanum-modified bentonite in combination with a submerged macrophyte (Vallisneria denseserrulata) on phosphorus inactivation and macrophyte growth: A mesocosm study.

The combination of chemical phosphorus (P) inactivation and submerged macrophyte transplantation has been widely used in lake restoration as it yields stronger effects than when applying either method alone. However, the dose effect of chemical materials on P inactivation when used in combination with submerged macrophytes and the influences of the chemicals used on the submerged macrophytes growth remain largely unknown. In this study, we investigated P inactivation in both the water column and the sediment, and the responses of submerged macrophytes to Lanthanum modified bentonite (LMB) in an outdoor mesocosm experiment where Vallisneria denseserrulata were transplanted into all mesocosms and LMB was added at four dosage levels, respectively: control (LMB-free), low dosage (570 g m-2), middle dosage (1140 g m-2), and high dosage (2280 g m-2). The results showed that the combination of LMB dosage and V. denseserrulata reduced TP in the water column by 32%-38% compared to V. denseserrulata alone, while no significant difference was observed among the three LMB treatments. Porewater soluble reactive P, two-dimensional diffusive gradient in thin films (DGT)-labile P concentrations, and P transformation in the 0-1 cm sediment layer exhibited similar trends along the LMB dosage gradient. Besides, LMB inhibited plant growth and reduced the uptake of mineral elements (i.e., calcium, manganese, iron, and magnesium) in a dosage-dependent manner with LMB. LMB may reduce plant growth by creating a P deficiency risk for new ramets and by interfering with the uptake of mineral elements. Considering both the dose effect of LMB on P inactivation and negative effect on macrophyte growth, we suggest a "small dosage, frequent application" method for LMB application to be used in lake restoration aiming to recover submerged macrophytes and clear water conditions.

Assessment of osteopontin as an early nephrotoxicity indicator in human renal proximal tubule cells and its application in evaluating lanthanum-induced nephrotoxicity.

Nephrotoxicity is a common adverse effect induced by various chemicals, necessitating the development of reliable toxicity screening models for nephrotoxicity assessment. In this study, we assessed a group of nephrotoxicity indicators derived from different toxicity pathways, including conventional endpoints and kidney tubular injury biomarkers such as clusterin (CLU), kidney injury molecule-I (KIM-1), osteopontin (OPN), and neutrophil gelatinase-associated lipocalin (NGAL), using HK-2 and induced pluripotent stem cells (iPSCs)-derived renal proximal tubular epithelial-like cells (PTLs). Among the biomarkers tested, OPN emerged as the most discerning and precise marker. The predictive potential of OPN was tested using a panel of 10 nephrotoxic and 5 non-nephrotoxic compounds. The results demonstrated that combining OPN with the half-maximal inhibitory concentration (IC50) enhanced the diagnostic accuracy in both cellular models. Additionally, PTLs cells showed superior predictive efficacy for nephrotoxicity compared to HK-2 cells in this investigation. The two cellular models were utilized to evaluate the nephrotoxicity of lanthanum. The findings indicated that lanthanum possesses nephrotoxic properties; however, the degree of nephrotoxicity was relatively low, consistent with the outcomes of in vivo experiments.

Lanthanum-doped magnetic biochar activating persulfate in the degradation of florfenicol.

In this study, lanthanum-doped magnetic biochar (LaMBC) was synthesized from bagasse by co-doping iron salt and lanthanum salt, and it was characterized for its application in the activation of persulfate (PS) in the degradation of Florfenicol (FLO). The results indicated that the LaMBC/PS system consistently achieved a degradation efficiency of over 99.5 %, with a reaction rate constant 4.71 times as that of MBC. The mechanism of FLO degradation suggested that O2•- and •OH played dominant roles, contributing 40.92 % and 36.96 %, respectively, during FLO degradation. Through physicochemical characterization and quenching experiments, it can be concluded that the key reasons for the enhancement of MBC activation performance are as follows: (1) Lanthanum doping in magnetized biochar increased the Fe(II) content in MBC. (2) Lanthanum doping significantly improved the adsorption capacity of LaMBC, increased the concentration of pollutants on the catalyst surface and effectively enhancing the reaction rate. (3) Lanthanum doping effectively increased the surface Fe(II) content during the reaction process in LaMBC, promoted the generation of active oxygen species in PS. This study delves into synthesizing and applying LaMBC for PS activation and FLO removal. The emphasis is on comprehensively characterizing and experimenting to elucidate the mechanism, proposing an innovative approach for efficiently degrading antibiotic wastewater.

Tuning microscopic structure of La-MOFs via ligand engineering effect towards enhancing phosphate adsorption.

The selection of different organic ligands when synthesizing metal organic framework (MOFs) can change their effects on the adsorption performance. Here, four La-MOFs adsorbents (La-SA, La-FA, La-TA and La-OA) with different organic ligands and structures were synthesized by solvothermal method for phosphate adsorption, and the relationship between their adsorption properties and structures was established. Among four La-MOFs, their phosphate adsorption capacities and adsorption rates followed La-SA > La-FA > La-TA > La-OA. The results indicated that average pore diameter played a key role in phosphate adsorption and there was a positive correlation between average pore diameter and adsorption capacity (R2 = 0.86). Coexisting ion experiments showed that phosphate adsorptions on three La-MOFs (La-SA, La-FA and La-TA) were inhibited in the presence of CO32- and HCO3-. The inhibition of CO32- was the most pronounced and the results of redundancy analysis pointed out that it was mainly due to the change of pH value. In contrast, La-OA showed enhanced phosphate adsorption in the presence of CO32- and HCO3-, and the combination of pH experiments showed that phosphate adsorption by La-OA was increased under alkaline conditions. Further combined with FT-IR, XRD, high resolution energy spectra of XPS (La 3d, P 2p and O 1s) and XANES, the adsorption mechanisms were derived electrostatic attraction, chemical precipitation and inner sphere complexation, and the last two were identified as the main mechanisms. Moreover, it can be identified from XPS 2p that the phosphate adsorption on La-FA and La-OA were mainly in the LaPO4 state, while La-SA and La-TA mainly existed in the form of LaPO4·xH2O crystals and inner sphere complexes. From the perspective of material morphology, this work provides a thought for the rational design of MOFs with adjustable properties for phosphate adsorption.

Combining lanthanum-modified bentonite and calcium peroxide to enhance phosphorus removal from lake sediments.

Lanthanum-modified bentonite (LMB) and calcium peroxide (CP) are known for their effective removal phosphorus (P) capacities. The present study aims to investigate the effects of the combined use of LMB and CP（LMB + CP）on the sediment P, dissolved organic matter (DOM) and iron (Fe) concentrations through a 90-day incubation experiment. The combined treatment showed strong removal effects on sediment P and DOM. Indeed, the SRP and DOM concentrations in the 0-10 cm sediment layer decreased following the combined application of LMB and CP by 40.67 and 28.95%, respectively, compared to those of the control group (CK). In contrast, the HCl-P in the 0-5 cm sediment layer increased following the combined treatment by 13.28%. In addition, compared with the single application of LMB, the LMB + CP treatment significantly reduced the soluble Fe (Ⅱ) in the sediment pore water and promoted the oxidation of Fe. Therefore, LMB + CP can enhance the removal of internal P from sediments. The DOM removal and Fe oxidation in sediment pore waters are beneficial for enhancing the adsorption of P by LMB. On the other hand, the single and combined applications of LMB and CP increased the richness of the sediment microbial communities while exhibiting slight effects on their diversity. According to the results of this study, the combined use of LMB and oxidizing materials represents a novel method for treating lakes with high internal phosphorus and DOM loads in sediments.

Understanding the effects of A-site Ag-doping on LaCoO3 perovskite for NO oxidation: Structural and magnetic properties.

The partial substitution of A-site in perovskites is a major strategy to enhance the catalytic oxidation activity. This study explores the use of silver (Ag) to partially replace the lanthanum (La) ion at the A-site in LaCoO3 perovskite, investigating the role of Ag in the ABO3 perovskite structure, elucidating the nitric oxide (NO) oxidation mechanism over La1-xAgxCoO3 (x = 0.1-0.5) perovskites. La0.7Ag0.3CoO3 with an Ag-doping amount of 0.3, exhibited the highest NO oxidation activity of 88.5% at 275 °C. Characterization results indicated that Ag substitution enhanced the perovskite, maintaining its original phase structure, existing in the form of a mixture of Ag0 and Ag+ in the La1-xAgxCoO3 (x = 0.1-0.5) perovskites. Notably, Ag substitution improved the specific surface area, reduction performance, Co3+, and surface adsorption oxygen content. Additionally, the study investigated the relationship between magnetism and NO oxidation from a magnetism perspective. Ag-doping strengthened the magnetism of La-Ag perovskite, resulting in stronger adsorption of paramagnetic NO. This study elucidated the NO oxidation mechanism over La-Ag perovskite, considering structural and magnetic properties, providing valuable insights for the subsequent development and industrial application of high oxidation ability perovskite catalysts.

The investigation of ion association characteristics in lanthanum sulfate solution by the density functional theory and molecular dynamics simulations.

The ion association behavior in aqueous lanthanum sulfate solutions was investigated using density functional theory (DFT). The structures and properties of [La(SO4)m·(H2O)n](3-2m) clusters, where m = 1 to 3 and n = 1 to 9, were examined at the PBE0/6-311+G(d, p) level. The results show that Lanthanum sulfate hydrated clusters exist in the aqueous solution's microscopic state of contact ion pairs (CIP). [La(SO4)(H2O)n]+ and [La(SO4)2·(H2O)n]-, and [La(SO4)3·(H2O)n]3- clusters approximately reach the saturation of the first water shell at n = 7 and 6 and 3. [La(SO4)2·(H2O)6]- and [La(SO4)3·(H2O)3]3- clusters have lower binding energy than [LaSO4·(H2O)n]+. This indicates that lanthanum sulfate tends to aggregate in an aqueous solution. Compared to the gas-phase cluster structures, the distance of R(La-O)H2O expands in the PCM solvent model, while R(La-O)SO4 contracts. The hydration energy of LaSO4·(H2O)7, La(SO4)2·(H2O)6, and La(SO4)3·(H2O)3 were -76.5, -54.1 and -332.0 kcal/mol, respectively. The molecular dynamics simulation results show that La is more inclined to coordinate with sulfate's oxygen than water's oxygen, and the coordination number of water around La3+ is 6.075. These results are consistent with the calculated results by DFT.

Exploring the multifaceted impact of lanthanides on physiological pathways in human breast cancer cells.

Lanthanum (La) and cerium (Ce), rare earth elements with physical properties similar to calcium (Ca), are generally considered non-toxic when used appropriately. However, their ions possess anti-tumor capabilities. This investigation explores the potential applications and mechanisms of LaCl3 or CeCl3 treatment in triple-negative breast cancer (TNBC) cell lines. TNBC, characterized by the absence of estrogen receptor (ERα), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2) expression, is prone to early metastasis and resistant to hormone therapy. Our results demonstrate that La/Ce treatment reduces cell growth, and when combined with cisplatin, it synergistically inhibits cell growth and the PI3K/AKT pathway. La and Ce induce oxidative stress by disrupting mitochondrial function, leading to protein oxidation. Additionally, they interfere with protein homeostasis and induce nucleolar stress. Furthermore, disturbance in F-actin web formation impairs cell migration. This study delves into the mechanism by which calcium-like elements La and Ce inhibit breast cancer cell growth, shedding light on their interference in mitochondrial function, protein homeostasis, and cytoskeleton assembly.

One-step synthesis of phytic acid-assisted hydrochar boost selective sorption and in situ passivation of lanthanum.

The rare earth metal element lanthanum (La) possesses carcinogenic, genotoxic, and accumulative properties, necessitating urgent development of an efficient and cost-effective method to remove La. However, current sorbents still encounter challenges such as poor selectivity, low sorption capacity, and high production costs. This study therefore proposes a promising solution: the creation of phytic acid-assisted sludge hydrochars (P-SHCs) to eliminate La from water and soil environments. This method harnesses phytic acid's exceptional binding ability and the economical hydrothermal carbonization process. P-SHCs exhibit robust sorption affinity, fast sorption kinetics, and excellent sorption selectivity for La when compared with pristine hydrochars (SHCs). This advantage arises from the remarkable binding ability of phosphate functional groups (polyphosphates) on P-SHCs, forming P-O-La complexes. Moreover, P-SHCs demonstrate sustained sorption efficiency across at least five cycles, with a slight decrease attributed to the loss of phosphorus species and mass during recycling. Furthermore, P-SHCs demonstrated superior economic feasibility, with a higher estimated cost-benefit ratio than that of other sorbents. Our study further validates the exceptional passivation capability of P-SHCs, showcasing relative stabilization efficiency ranging from 37.6 % to 79.6 % for La contamination. Additionally, acting as soil passivation agents, P-SHCs foster the enrichment of specific soil microorganisms such as Actinobacteria and Proteobacteria, capable of solubilizing phosphorus and resisting heavy metals. These findings present novel ideas and technical support for employing P-SHCs in combatting environmental pollution stemming from rare earth metals.