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Background: Radiopharmaceutical therapy (RPT) uses radionuclides that decay via one of three therapeutically relevant decay modes (alpha, beta, and internal conversion (IC) / Auger electron (AE) emission) to deliver short range, highly damaging radiation inside of diseased cells, maintaining localized dose distribution and sparing healthy cells. Antimony-119 (119Sb, t1/2 = 38.19 h, EC = 100%) is one such IC/AE emitting radionuclide, previously limited to in silico computational investigation due to barriers in production, chemical separation, and chelation. A theranostic (therapeutic/diagnostic) pair can be formed with 119Sb's radioisotopic imaging analogue 117Sb (t1/2 = 2.80 h, Eγ = 158.6 keV, Iγ = 85.9%, β+ = 262.4 keV, Iβ+ = 1.81%). Results: Within, we report techniques for sustainable and cost-effective production of pre-clinical quality and quantity, radionuclidically pure 119Sb and 117Sb, novel low energy photon measurement techniques for 119Sb activity determination, and physical yields for various tin target isotopic enrichments and thicknesses using (p, n) and (d, n) nuclear reactions. Additionally, we present a two-column separation providing a radioantimony yield of 73.1% ± 6.9% (N = 3) and tin separation factor of (6.8 ± 5.5) x 105 (N = 3). Apparent molar activity measurements for deuteron produced 117Sb using the chelator TREN-CAM were measured at 42.4 ± 25 MBq 117Sb/µmol (1.14 ± 0.68 mCi/µmol), and we recovered enriched 119Sn target material at a recycling efficiency of 80.2% ± 5.5% (N = 6) with losses of 11.6 mg ± 0.8 mg (N = 6) per production. Conclusion: We report significant steps in overcoming barriers in 119Sb production, chemical isolation and purification, enriched target material recycling, and chelation, helping promote accessibility and application of this promising therapeutic radionuclide. We describe a method for 119Sb activity measurement using its low energy gamma (23.87 keV), negating the need for attenuation correction. Finally, we report the largest yet-measured 119Sb production yields using proton and deuteron irradiation of natural and enriched targets and radioisotopic purity > 99.8% at end of purification. [ABSTRACT FROM AUTHOR]

ABSTRACT Tin complexes, Sn(IV)‐TSC 1·MeOH and Sn(IV)‐TSC 2, with thiosemicarbazones possessing an N2S ligation system [TSC 1 = 4‐(4‐nitrophenyl)‐1‐((pyridin‐2‐yl)methylene)thiosemicarbazide and TSC 2 = 4‐(2‐methoxyphenyl)‐1‐((pyridin‐2‐yl)methylene)thiosemicarbazide] were prepared and structurally characterized. These complexes are found in the space groups P1¯$$ \overline{1} $$ and P21/n, respectively, with their tin atoms in octahedral environments established by three chlorine atoms and an anionic thiosemicarbazone ligand. All compounds (20 mg/mL in DMSO) were tested for their antibacterial [against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa] and antifungal [against Aspergillus flavus and Candida albicans] properties. The ligand TSC 2 displayed inhibitions in the S. aureus and E. coli cultures (with zones of 11 and 10 mm, respectively), whereas Sn(IV)‐TSC 1·MeOH and Sn(IV)‐TSC 2 inhibited all bacteria with 11–15 and 14–16 mm, respectively. In the fungal cultures, only Sn(IV)‐TSC 1·MeOH (10 mm) showed an inhibition zone against A. flavus. The ligands' antiproliferative activities were determined against human cancer cells of the lung, breast, liver, and colon, and both ligands afforded the highest activity against the breast MCF‐7 cells. The complexation enhanced the ligands' activities as TSC 1, TSC 2, Sn(IV)‐TSC 1·MeOH, and Sn(IV)‐TSC 2 afforded respective IC50 values of 52.4, 153.7, 18.3, and 63.9 μM. However, against normal baby hamster kidney (BHK) cells, these compounds showed IC50 data of 54.8, 82.7, 16.1, and 15.3 μM, respectively. [ABSTRACT FROM AUTHOR]

Installing fluoroalkyl motifs into biorelevant indoles is particularly interesting due to their ubiquitous presence in drug molecules. Herein, we demonstrate the regioselective C4 fluoroalkoxylation of indoles using fluoroalcohols via palladium‐catalyzed chelation‐assisted C─H activation. The weak chelating benzoyl moiety at the C3 position acts as a directing group for remote C(4)─H fluoroalkoxylation of diversely substituted indoles. This methodology demonstrates a high level of regioselectivity and tolerates a range of crucial functional groups, yielding diverse trifluoroalkoxylated indoles in moderate to good yields. Removal of directing/protecting groups and further functionalization established the synthetic utility of the methodology. A preliminary mechanistic investigation is conducted by isolating the palladacycle intermediate and performing the deuterium scrambling study. [ABSTRACT FROM AUTHOR]

AbstractPlatelet-derived growth factor (PDGF)-induced signalling via PDGF receptor β (PDGFRβ) leads to activation of downstream signalling pathways which regulate multiple cellular responses. It is unclear how PDGFRβ is degraded; both lysosomal and proteasomal degradation have been suggested. In this study, we have characterised the proteolytic cleavage of ligand-activated PDGFRβ, which results in two fragments: a larger fragment containing the extracellular domain, the transmembrane segment, and a part of the intracellular juxtamembrane region with a molecular mass of ∼130 kDa, and an intracellular ∼70 kDa fragment released into the cytoplasm. The proteolytic processing did not take place without internalisation of PDGFRβ. In addition, chelation of intracellular Ca2+ inhibited proteolytic processing. Inhibition of the proteasome affected signal transduction by increasing the phosphorylation of PDGFRβ, PLCγ, and STAT3 while reducing it on Erk1/2 and not affecting Akt. The proteolytic cleavage was observed in fibroblasts or cells that had undergone epithelial-mesenchymal transition. [ABSTRACT FROM AUTHOR]

A stable self-assembled 2-hydroxyphosphonoacetic acid (HPAA) layer was constructed on the Zn surface via chelation. This HPAA protective layer significantly inhibits the water-related side reactions and suppresses Zn dendrite growth. Consequently, the Zn-HPAA-1h anode shows a long cycling lifetime of 650 h in a symmetric cell at 30.0 mA cm−2. Also, the Zn-HPAA-1h//V2O5 full cell demonstrates a high capacity of 154.1 mA h g−1 after 1000 cycles at 2 A g−1. This study provides a new strategy for developing dendrite-free Zn anodes. [ABSTRACT FROM AUTHOR]

Objectives: To report the outcomes of novel modified transepithelial phototherapeutic keratectomy (PTK) in treating band keratopathy (BK). Methods: A retrospective analysis was performed on patients who underwent PTK for BK at the Sussex Eye Laser Clinic, Nuffield Health, Brighton. Patients with BK obscuring the visual axis, affecting visual acuity, or causing discomfort were considered for PTK. All the patients underwent preoperative evaluation, including preoperative corneal topography and optical coherence tomography. Modified transepithelial PTK was performed without using EDTA for chelation or alcohol for epithelium debridement. Patients were followed up for one week and then every two weeks after that until two months. Preoperative and postoperative best corrected visual acuities (BCVA) were compared using a paired t-test. Results: We studied 15 eyes of nine patients undergoing novel PTK for BK. The mean age was 80 ± 5.73 years. The mean pre-treatment visual acuity was 0.68 ± 0.17 logMAR (range: 0.6 logMAR to 1 logMAR) and improved to 0.22 ± 0.09 logMAR (p < 0.05), ranging from 0.18 to 0.48 logMAR at two months following PTK. None of the patients complained of ocular discomfort following the procedure. A repeat procedure was not required for any of these patients. Conclusions: Modified transepithelial PTK is an effective procedure for improving visual outcomes in patients with band keratopathy and should be considered for the treatment of band keratopathy. [ABSTRACT FROM AUTHOR]

The intensive interest in expanded porphyrins can be attributed to their appealing photoelectric and coordination behavior. In this work, an N‐confused heptaphyrin 1 was synthesized by an acid‐catalyzed [3+4] condensation reaction. The introduction of an N‐confused pyrrolic unit into the heptaphyrin macrocycle led to the formation of a figure‐eight‐like conformation with nonsymmetrical "NNNN" and "NNNC" coordination cavities employable for bimetallic coordination. As a result, chelation of 1 with Zn(II) and Cu(II) afforded mono‐Zn(II) complex 2 and bis‐Cu(II) complex 3, respectively, with the metal atoms exhibiting distorted square‐planar geometries. In complex 3, an oxygen atom is attached to the α‐C atom of N‐confused pyrrole D, and thus the N and C atoms of ring D participate in coordination within the two cavities. Interestingly, treatment of 1 with Cs2CO3 in MeOH resulted in regioselective substitution of all the seven para‐F atoms in the meso‐C6F5 groups as well as the α‐H of ring D by eight methoxy moieties. Complex 3 displays a red‐shifted absorption band edge of ca. 2200 nm, compared to that of ca. 1600 nm observed for 1. This work provides an example of incorporating an N‐confused pyrrole to construct expanded porphyrins with distinctive coordination behavior and tunable NIR absorption. [ABSTRACT FROM AUTHOR]

The selective functionalization of 1,3-bis(boronic) esters holds the potential for creating diverse molecular structures, particularly through the late-stage functionalization of the remaining C–B bond. By employing distinct organometallic reagents, we have developed a method for regiodivergent alkynylation of 1,3-bis(boronic) esters, facilitated by unique chelation patterns. Notably, this methodology effectively overcomes limitations commonly encountered in radical chemistry, which generates only monoselective downstream targets. Furthermore, the compounds synthesized through this approach can serve as significant building blocks, contributing to the construction of molecular complexity. [ABSTRACT FROM AUTHOR]

A salt of 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) was commercialized some years ago. This so-called Dual Rinse (DR) HEDP has been tested for its combined actions and interactions with pure sodium hypochlorite (NaOCl) solutions. The aim of this study was to assess DR interactions with NaOCl solutions containing proprietary additives. Designated endodontic NaOCl solutions that come at 2 different strengths (2% and 5.25%), and without or with additives (Chloraxid and Chloraxid Extra, respectively) were tested. Some of their key chemical and physical properties were determined in the presence or absence of HEDP (9%) in the solution. In addition, soft tissue dissolution efficacy of test and control solutions was assessed in extracted teeth (n = 10 per group, 90 teeth in total). The NaOCl content in the 2% Chloraxid solutions was slightly above, that in the 5.25% solutions below the labeled concentration. The additives in the Chloraxid Extra solutions neither altered their surface tension nor their viscosity. The addition of HEDP to any of the tested NaOCl solutions reduced their pH, and increased their surface tension and viscosity. HEDP-induced available chlorine loss over the first hour was similar between all NaOCl solutions. Soft tissue dissolution in the root canals was affected by NaOCl concentration, but neither by any proprietary NaOCl additive in the Chloraxid solutions, nor the addition of DR HEDP. Proprietary additives had no influence on any of the tested parameters, including surface tension of the "Extra" solutions. The increased viscosity of combined NaOCl/HEDP solutions deserves further attention. [ABSTRACT FROM AUTHOR]

2-Mercaptomethylbenzo[d]imidazole (2-MMBI) derivatives were designed and synthesized as tyrosinase (TYR) chelators using 2-mercaptomethylimidazole scaffolds. Seven of the ten 2-MMBI derivatives exhibited stronger inhibition of mushroom TYR activity than kojic acid. Their ability to chelate copper ions was demonstrated through experiments using the copper chelator pyrocatechol violet and assays measuring TYR activity in the presence or absence of exogenous CuSO4. The inhibition mechanisms of derivatives 1, 3, 8, and 9, which showed excellent TYR inhibitory activity, were elucidated through kinetic studies and supported by the docking simulation results. Derivatives 3, 7, 8, and 10 significantly inhibited cellular TYR activity and melanin production in B16F10 cells in a dose-dependent manner, with stronger potency than kojic acid. Furthermore, in situ, derivatives 7 and 10 showed stronger inhibitory effects on B16F10 cell TYR activity than kojic acid. Six derivatives, including 8, showed highly potent depigmentation in zebrafish larvae, outpacing kojic acid even at 200–670 times lower concentrations. Additionally, all derivatives could scavenge for reactive oxygen species without causing cytotoxicity in epidermal cells. These results suggested that 2-MMBI derivatives are promising anti-melanogenic agents. [ABSTRACT FROM AUTHOR]

Summary The iron chelator deferasirox (DFX) is effective in the treatment of iron overload. In certain patients with myelodysplastic syndrome, DFX can also provide a dramatic therapeutic benefit, improving red blood cell production and decreasing transfusion requirements. Nuclear Factor‐kappa B (NF‐kB) signalling has been implicated as a potential mechanism behind this phenomenon, with studies focusing on the effect of DFX on haematopoietic progenitors. Here, we examine the phenotypic and transcriptional effects of DFX throughout myeloid cell maturation in both murine and human model systems. The effect of DFX depends on the stage of differentiation, with effects on mitochondrial reactive oxygen species (ROS) production and NF‐kB pathway regulation that vary between progenitors and neutrophils. DFX triggers a greater increase in mitochondrial ROS production in neutrophils and this phenomenon is mitigated when cells are cultured in hypoxic conditions. Single‐cell transcriptomic profiling revealed that DFX decreases the expression of NF‐kB and MYC (c‐Myc) targets in progenitors and decreases the expression of PU.1 (SPI1) gene targets in neutrophils. Together, these data suggest a role of DFX in impairing terminal maturation of band neutrophils. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial agents (AMAs) are essential for treating infections. A part of AMAs chelate with metal cations (MCs), reducing their blood concentrations. That drug-drug interaction could lead to a reduction of therapeutic efficacy and the emergence of drug-resistant bacteria. However, prescriptions ordering concomitant intake (co-intake) of AMAs and MCs are frequently seen in clinical settings. A method for preventing such prescriptions is urgently needed. Methods: We implemented pop-up alerts in the hospital's ordering and pharmacy dispensation support system to notify the prescriptions ordering co-intake of AMAs and MCs for physicians and pharmacists, respectively. To assess the effectiveness of the pop-up alerts, we investigated the number of prescriptions ordering co-intake of AMAs and MCs and the number of pharmacist inquiries to prevent co-intake of AMAs and MCs before and after the implementation of pop-up alerts. Results: Before the implementation of pop-up alerts, 84.5% of prescriptions containing AMA and MCs ordered co-intake of AMAs and MCs. Implementing pop-up alerts time-dependently reduced the proportion of prescriptions ordering co-intake of AMAs and MCs to 43.8% and 29.5% one year and two years later, respectively. The reduction of tetracycline-containing prescriptions was mainly significant. Before the implementation of pop-up alerts, the proportion of prescriptions in which pharmacists prevented co-intake of AMAs and MCs was 3.4%. Implementing pop-up alerts time-dependently increased proportions of such prescriptions to 20.9% and 28.2% one year and two years later. Conclusion: Implementing pop-up alerts reduced prescriptions ordering co-intake of AMAs and MCs and accelerated pharmacists to prevent co-intake of AMAs and MCs. The implementation of dual pop-up alerts in the hospital's ordering and pharmacy dispensation support system could help prevent co-intake of AMAs and MCs. [ABSTRACT FROM AUTHOR]

Addressing the slow electrochemical kinetics and electrode pulverization of sodium ion batteries (SIBs) is needed to continuously develop advanced anode materials. Molybdenum telluride (MoTe 2) is considered promising for SIBs anodes due to its wider interlayer distance, faster electronic conductivity, and weaker interlayer force. However, the nanoparticle aggregation and layered structure collapse caused by bond breakage weaken its inherent advantages for excellent sodium storage performance. Herein, hierarchically nanostructured regulation and surface coating of MoTe 2 based SIB anodes are simultaneously achieved by employing Mo-PDA as precursors through a concise and effective method containing chelation, preoxidation and tellurization. The microstructure and morphology of MoTe 2 /C composites can be facilely regulated by controlling the chelation time and tellurization temperature. The as-synthesized MoTe 2 /C-6h-600 electrode exhibits encouraging Na+ storage performance, which delivers discharge capacitances of 290.7 mAh g−1 (0.1 A g−1) and 161.1 mAh g−1 (1.0 A g−1) after hundreds and thousands cycles, respevtively. Furthermore, the assembled full cell of MoTe 2 /C-6h-600//NVP delivers a stable reversible capacitance of 103 mAh g−1, which is promising for future practical applications. [Display omitted] • Hierarchical nanosheet self-assembled MoTe 2 /C are successfully synthesized. • Effects of tellurization temperature and chelation time are systematically investigated. • MoTe 2 /C-6h-600 exhibits excellent Na+ storage performance for half/full cells. • MoTe 2 /C-6h-600 can be successfully applied in an electronic gyroscope. [ABSTRACT FROM AUTHOR]

In this study, a novel strategy is proposed to prepare eco-friendly flame-retardant cotton fabrics, where chloroacetic acid (MCA) and L-glutamic acid (L-Glu) are used as raw materials to enhance the chelation ability between carboxyl groups (-COO-) and calcium ions (Ca2+). The morphological and structural characterizations of the prepared cotton fabrics indicate that the three free hydroxy groups (2, 3, 6) in the cellulose macromolecule are chemically modified to graft a large number of carboxyl groups, and Ca2+ ions are successfully chelated on the surface of cotton fabric. The thermal stability of cotton fabrics is greatly improved in both air and nitrogen atmosphere. The residual mass of flame-retardant cotton fabric (COT-Glu–Ca) is much higher than that of original cotton fabric, increasing from 0.03% to 5.6% in air and from 8.1% to 28.2% in N2, respectively. At the same time, the limiting oxygen index (LOI) of COT-Glu–Ca fabric is as high as 33.6%. The prepared flame-retardant cotton fabric can undergo vertical combustion tests with a char length of only 53 mm, and afterflame and afterglow are not observed, which proves that the grafted cotton fabric had a good flame retardancy due to a series of modifications and adsorption of Ca2+ ions. The properties of the cotton fabric, including tensile strength, whiteness, and moisture absorption, are all retained at a satisfactory level. Overall, this study provides a promising strategy for manufacturing eco-friendly, phosphorus-free, halogen-free, and fire-resistant cotton fabrics with enhanced metal ion chelation ability. [ABSTRACT FROM AUTHOR]

Two complexes of Sn (IV), Sn (IV)‐TSC 1 and Sn (IV)‐TSC 2, with the ligands 4‐(2,4‐dimethylphenyl)‐1‐([pyridin‐2‐yl]methylene)thiosemicarbazide (TSC 1) and 4‐(2,5‐dimethoxyphenyl)‐1‐([pyridin‐2‐yl]methylene)thiosemicarbazide (TSC 2) were synthesized. X‐ray crystallographic investigation of Sn (IV)‐TSC 2 afforded valuable information on its octahedral geometry, monoclinic lattice and C 1 2/c 1 space group. The ligands are monoanionic tridentate via a deprotonated thiol sulfur atom and two nitrogen atoms of pyridine and azomethine moieties. These atoms coordinate tin alongside three independent chlorine atoms making the tin atoms in the complexes tetravalent, despite of incorporating tin (II) chloride in the reactions. Solutions of the ligands TSC 1 and TSC 2 (20 mg/ml in dimethyl sulfoxide) induced growth inhibitions only to Staphylococcus aureus (14 and 10 mm) and Escherichia coli (15 and 10 mm) bacteria. But the complexes displayed activities against four bacterial species, that is, S. aureus, E. coli, Bacillus subtilis and Pseudomonas aeruginosa (complex Sn (IV)‐TSC 1, complex Sn (IV)‐TSC 2 and ampicillin showed inhibition diameters with 12–14, 13–14 and 21–26 mm). All TSC ligands and coordination compounds induced cytotoxicity in MCF‐7 cancer and BHK normal cells. The compounds TSC 1, TSC 2, Sn (IV)‐TSC 1, Sn (IV)‐TSC 2 and doxorubicin inhibited the MCF‐7 (BHK) cells with IC50 values of 68.9 (126.6), 145.4 (110.6), 22.6 (16.7), 34.2 (16.1) and 9.66 (36.42) μM, respectively. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Preventing metal‐catalyzed lipid oxidation in food products, which decreases nutritional value and sensory quality, is crucial in the food industry. This is typically achieved through the use of metal‐chelating molecules. While the ferrozine assay is widely used to screen protein hydrolysates for metal chelating activity, it has proven difficult to use with pure peptides. This study evaluates the potential of surface plasmon resonance (SPR) and electrically switchable nanolever technology (switchSENSE®) as alternative screening methods. Unfortunately, solubility issues and large standard deviations precluded a direct correlation between the ferrozine assay and these biosensor techniques. Both techniques, however, were able to quantitatively distinguish between two peptides with very similar sequences despite the absence of a correlation between dissociation constants determined by SPR and switchSENSE®. This study highlights the potential of SPR and switchSENSE® for screening the metal chelating activity of pure peptides, advancing the understanding of peptide‐metal ion interactions. [ABSTRACT FROM AUTHOR]

This mini‐review comprehensively outlines the latest advancements in protecting zinc anodes in zinc‐ion batteries (ZIBs) through chelation mechanisms. Chelation involves the coordination of ligands with Zn2+, offering promising strategies to address challenges such as dendrite formation and hydrogen evolution reactions. However, there is a lack of comprehensive and unified evaluation of chelation's protective effect on the zinc anode, which hinders a thorough assessment of chelation's effectiveness. Recent studies have demonstrated the excellent protective performance of chelation in altering solvation structures, modifying SEI structures, and selectively adsorbing species on the zinc anode. Furthermore, while chelation demonstrates significant benefits for the zinc anode, its impact on cathode materials must also be considered. Proper selection of chelation strengths and compatible cathode materials is essential for overall battery performance. Future research directions include exploring the effects of different ligands and coordination numbers on battery performance and extending chelation strategies to other secondary metal batteries. Understanding and optimizing chelation mechanisms are critical for advancing the development of high‐performance ZIBs and other metal‐ion battery technologies. [ABSTRACT FROM AUTHOR]

Chelating gels may initially assist in root canal preparations to help establish a glide path. While irrigation surveys have investigated liquid chelators and gels to a minor extent, no endodontic survey has focused on EDTA gels and why clinicians use them. All 395 members of the Australian Society of Endodontology (ASE) were emailed an 11-question survey concerning chelation gel usage via Qualtrics. Paper copies were also distributed at ASE events. Descriptive statistics were performed for practitioner and chelating gel data. Cross-tabulations of the practitioner type with the case percentage usage of gels were analyzed with the chi square test (adjusted p value < 0.0083). The overall response rate was 181/395 (46%). For 174 eligible responses, those who never/rarely used a gel were as follows: endodontic residents 12/14 (86%), endodontists 53/71 (75%), general dentists 39/86 (45%), and other members 0% (0/3). Most gel users said that gels helped establish a glide path. Those who never/rarely used chelating gels commented that they held no benefits over liquid EDTA. Endodontists were less likely to use a chelation gel than general dentists (p < 0.0083). Older clinicians had higher gel usage than younger ASE members (p < 0.0083), indicating a possible trend to diminished gel usage over time amongst ASE members. In conclusion, most ASE members find no need for a chelating gel, raising questions about their clinical effectiveness. Studies would therefore be warranted to investigate gel efficacy and improved clinical outcomes. [ABSTRACT FROM AUTHOR]

Crystalluria, characterized by the formation of calcium oxalate crystals, is a common urinary disorder. While increasing urinary volume is a traditional approach to manage this condition, novel therapeutic strategies are being explored. Lemon juice (LJ), rich in citric acid, is of particular interest due to its calcium ion chelating properties. This study evaluated the in vitro potential of LJ to inhibit calcium oxalate crystal formation. Using specialized electrodes (CPE-GC) and various electrochemical techniques (SWV, CV, LV, EIS), we characterized the interactions between LJ and calcium ions. Our findings, obtained from a simplified model using calcium carbonate, demonstrate the ability of LJ to effectively complex calcium ions, thereby reducing their availability for crystal formation. Although these results are promising, it's important to note that the experimental conditions do not fully replicate the complexity of physiological urine. In vivo studies are therefore necessary to confirm the efficacy of LJ in a clinical setting. In conclusion, lemon juice appears to be a promising approach for preventing calcium oxalate crystal formation. Its mechanism of action, based on calcium ion chelation, offers an alternative to conventional treatments. However, further research is required to evaluate its clinical efficacy and optimize its usage. [ABSTRACT FROM AUTHOR]

Concern over heavy metal pollution has rapidly grown over the past few years due to rapid industrialization and population growth. These metal cations are known to have various detrimental effects on the environment, more so on humans and plants. To date, several technologies such as photocatalysis, adsorption and ion exchange have been employed to remove these heavy metal pollutants from the environment and specifically water. However, most of these methods suffer from several disadvantages that limit their application for the speciation of heavy metals, particularly at trace levels. Chelation extraction technique is thus emerging as a promising alternative for the removal of heavy metal cations as it is effective even at trace levels of the cations. In addition, chelation extraction has high selectivity as the nature of the chelating agent/ligand can be fine-tuned towards specific metal cations. This review article captures research findings reported over the past decade on the design and applications of chelating ligands in the removal of heavy metal cations from water. The main focus is on the ligand design, mode of administration, and optimum extraction conditions while also comparing these ligand moieties with other chelating compounds utilized in heavy metal extraction. A summary of the sources and effects of heavy metals in the environment as well as the existing technologies for heavy metal remediation are also highlighted. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Faculty of Pharmacy of Ankara University / Ankara Üniversitesi Eczacilik Fakültesi Dergisi is the property of Ankara University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study reports the development and evaluation of yttrium-90 (90Y) radiolabeled silica-coated iron oxide (SiO2-Fe3O4) resin microspheres for potential theranostic application in cancer radiation therapy. Iron oxide nanoparticles of average diameter 29.7 nm were synthesized via optimized co-precipitation and displayed superparamagnetic behavior ideal for MRI. Aminosilane surface functionalization enabled covalent conjugation of 1 mmol/g DTPA/DOTA chelators for labeling 2 mCi 90Y per 150 μg nanoparticles with 92 % efficiency when incubated for 45 mins at pH 5.5 and 50°C. In vitro stability assays in buffers and human serum showed excellent 90Y retention (>95 %) up to 48 hours. In vivo biodistribution in Wistar rats revealed extended nanoparticle circulation half-life of 5.2 hours and peak exposure of 22.4 %ID/g compared to rapid clearance of unconjugated 90Y chloride within 1 hour. Complete renal recovery by 72 hours and minimal bone accumulation (

Abstract Background Antimicrobial agents (AMAs) are essential for treating infections. A part of AMAs chelate with metal cations (MCs), reducing their blood concentrations. That drug-drug interaction could lead to a reduction of therapeutic efficacy and the emergence of drug-resistant bacteria. However, prescriptions ordering concomitant intake (co-intake) of AMAs and MCs are frequently seen in clinical settings. A method for preventing such prescriptions is urgently needed. Methods We implemented pop-up alerts in the hospital's ordering and pharmacy dispensation support system to notify the prescriptions ordering co-intake of AMAs and MCs for physicians and pharmacists, respectively. To assess the effectiveness of the pop-up alerts, we investigated the number of prescriptions ordering co-intake of AMAs and MCs and the number of pharmacist inquiries to prevent co-intake of AMAs and MCs before and after the implementation of pop-up alerts. Results Before the implementation of pop-up alerts, 84.5% of prescriptions containing AMA and MCs ordered co-intake of AMAs and MCs. Implementing pop-up alerts time-dependently reduced the proportion of prescriptions ordering co-intake of AMAs and MCs to 43.8% and 29.5% one year and two years later, respectively. The reduction of tetracycline-containing prescriptions was mainly significant. Before the implementation of pop-up alerts, the proportion of prescriptions in which pharmacists prevented co-intake of AMAs and MCs was 3.4%. Implementing pop-up alerts time-dependently increased proportions of such prescriptions to 20.9% and 28.2% one year and two years later. Conclusion Implementing pop-up alerts reduced prescriptions ordering co-intake of AMAs and MCs and accelerated pharmacists to prevent co-intake of AMAs and MCs. The implementation of dual pop-up alerts in the hospital's ordering and pharmacy dispensation support system could help prevent co-intake of AMAs and MCs.

Retained lead fragments from nonfatal firearm injuries pose a risk of lead poisoning. While chelation is well-established as a lead poisoning treatment, it remains unclear whether chelation mobilizes lead from embedded lead fragments. Here, we tested whether 1) DMSA/succimer or CaNa2EDTA increases mobilization of lead from fragments in vitro, and 2) succimer is efficacious in chelating fragment lead in vivo, using stable lead isotope tracer methods in a rodent model of embedded fragments. DMSA was >10-times more effective than CaNa2EDTA in mobilizing fragment lead in vitro. In the rodent model, succimer chelation on day 1 produced the greatest blood lead reductions, and fragment lead was not mobilized into blood. However, with continued chelation and over 3-weeks post-chelation, blood lead levels rebounded with mobilization of lead from the fragments. These findings suggest prolonged chelation will increase fragment lead mobilization post-chelation, supporting the need for long-term surveillance in patients with retained fragments.

This study draws inspiration from the chelating abilities of dopamine and tannic acids with Ca2+ in cement-based materials and explores the potential of green tea water (GTW) with tea polyphenols (TP) as the major soluble substance as a natural source of polyphenols available in people's daily lives. Hydration kinetics analysis reveals that GTW has both retarding and accelerating effects on cement hydration, with the latter being more prominent at lower concentrations. Properly adding GTW to cement can increase the compressive strengths of mortars by up to 16.7% at 3d, 12.2% at 7d, and 18.2% at 28d compared to the blank mortar. The microstructure of the optimal mortar shows grape-cluster-like nanoparticles that originate from the TP∼Ca intermediates that act as seeds for more hydration products. This effect is confirmed by using analytically pure TP to analyze its influence on the compressive strength of mortar. [ABSTRACT FROM AUTHOR]

The cycling performance of zinc‐ion batteries is greatly affected by dendrite formation and side reactions on zinc anode, particularly in scenarios involving high depth of discharge (DOD) and low negative/positive capacity (N/P) ratios in full cells. Herein, drawing upon principles of host–guest interaction chemistry, we investigate the impact of molecular structure of electrolyte additives, specifically the −COOH and −OH groups, on the zinc negative electrode through molecular design. Our findings reveal that molecules containing these groups exhibit strong adsorption onto zinc anode surfaces and chelate with Zn2+, forming a H2O‐poor inner Helmholtz plane. This effectively suppresses side reactions and promotes dendrite‐free zinc deposition of exposed (002) facets, enhancing stability and reversibility of an average coulombic efficiency of 99.89 % with the introduction of Lactobionic acid (LA) additive. Under harsh conditions of 92 % DOD, Zn//Zn cells exhibit stable cycling at challenging current densities of 15 mA ⋅ cm−2. Even at a low N/P ratio of 1.3, Zn//NH4V4O10 full cells with LA electrolyte exhibit high‐capacity retention of 73 % after 300 cycles, significantly surpassing that of the blank electrolyte. Moreover, in a conversion type Zn//Br static battery with a high areal capacity (~5 mAh ⋅ cm−2), LA electrolyte sustains an improved cycling stability of 700 cycles. [ABSTRACT FROM AUTHOR]

In the course of past two decade anthropogenic activities have reinforced, begetting soil and water defilement. A plethora of heavy metals alters and limits plant growth and yield, with opposing effect on agricultural productivity. Silicon often perceived as plant alimentary 'nonentity'. A suite of determinants associated with silicon have been lately discerned, concerning plant physiology, chemistry, gene regulation/expression and interaction with different organisms. Exogenous supplementation of silicon renders resistance against heavy-metal stress. Predominantly, plants having significant amount of silicon in root and shoot thus are barely prone to pest onset and manifest greater endurance against abiotic stresses including heavy-metal toxicity. Silicon-mediated stress management involves abatement of metal ions within soil, co-precipitation of metal ions, gene modulation associated with metal transport, chelation, activation of antioxidants (enzymatic and non-enzymatic), metal ion compartmentation and structural metamorphosis in plants. Silicon supplementation also stimulates expression of stress-resistant genes under heavy-metal toxicity to provide plant tolerance under stress conditions. Ergo, to boost metal tolerance within crops, immanent genetic potential for silicon assimilation should be enhanced. Current study, addresses the potential role and mechanistic interpretation of silicon induced mitigation of heavy-metal stress in plants. [ABSTRACT FROM AUTHOR]

Trap‐assisted non‐radiative recombination losses and moisture‐induced degradation significantly impede the development of highly efficient and stable inverted (p–i–n) perovskite solar cells (PSCs), which require high‐quality perovskite bulk. In this research, we mitigate these challenges by integrating thermally stable perovskite layers with Lewis base covalent organic frameworks (COFs). The ordered pore structure and surface binding groups of COFs facilitate cyclic, multi‐site chelation with undercoordinated lead ions, enhancing the perovskite quality across both its bulk and grain boundaries. This process not only reduces defects but also promotes improved energy alignment through n‐type doping at the surface. The inclusion of COF dopants in p–i–n devices achieves power conversion efficiencies (PCEs) of 25.64 % (certified 24.94 %) for a 0.0748‐cm2 device and 23.49 % for a 1‐cm2 device. Remarkably, these devices retain 81 % of their initial PCE after 978 hours of accelerated aging at 85°C, demonstrating remarkable durability. Additionally, COF‐doped devices demonstrate excellent stability under illumination and in moist conditions, even without encapsulation. [ABSTRACT FROM AUTHOR]

Wood‐derived carbons demonstrate great potential as self‐standing electrodes in energy storage/conversion applications, including supercapacitors and water‐splitting devices. However, the key challenge remains the rational customization of surface functionalities for optimized performance. This study introduces an innovative approach to self‐standing wood‐derived carbons with tailored nitrogen and metal functionalities. In contrast to traditional impregnation techniques, which offer limited precision in surface modification, this approach entails the intentional attachment of amidoxime groups to the wood substrates. These groups serve as nitrogen sources, and create abundant surface anchoring sites for metal ions due to the chelation between the amidoxime groups and metals. The resulting carbons feature uniform and high dispersion of nitrogen and metal functionalities, along with a distinctive hierarchical porosity combining interconnected open channels with abundant mesopores. As a proof‐of‐concept, different metals are incorporated (i.e., Mn, Co, Ni) into the amidoximated‐wood precursors, and the resulting self‐standing carbons showcase excellent performance in both supercapacitors and water‐splitting applications. Leveraging the specific chelating ability of amidoxime groups toward metal ions, this strategy holds great potential as a generic approach to systematically tailoring the surface functionalities of carbon‐based materials for various electrochemical energy storage/conversion processes. [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) serve vital physiological functions, but aberrant ROS production contributes to numerous diseases. Unfortunately, therapeutic progress targeting pathogenic ROS has been hindered by the limited understanding of whether the mechanisms driving pathogenic ROS differ from those governing physiological ROS generation. To address this knowledge gap, we utilised a cellular model of Parkinson's disease (PD), as an exemplar of ROS-associated diseases. We exposed SH-SY5Y neuroblastoma cells to the PD-toxin, MPP+ (1-methyl-4-phenylpyridinium) and studied ROS upregulation leading to cell death, the primary cause of PD. We demonstrate: (1) MPP+ stimulates ROS production by raising cytoplasmic Ca2+ levels, rather than acting directly on mitochondria. (2) To raise the Ca2+, MPP+ co-stimulates NADPH oxidase-2 (NOX2) and the Transient Receptor Potential Melastatin2 (TRPM2) channel that form a positive feedback loop to support each other's function. (3) Ca2+ exacerbates mitochondrial ROS (mtROS) production not directly, but via Zn2+. (4) Zn2+ promotes electron escape from respiratory complexes, predominantly from complex III, to generate mtROS. These conclusions are drawn from data, wherein inhibition of TRPM2 and NOX2, chelation of Ca2+ and Zn2+, and prevention of electron escape from complexes -all abolished the ability of MPP+ to induce mtROS production and the associated cell death. Furthermore, calcium ionophore mimicked the effects of MPP+, while Zn2+ ionophore replicated the effects of both MPP+ and Ca2+. Thus, we unveil a previously unrecognized signalling circuit involving NOX2, TRPM2, Ca2+, Zn2+, and complex III that drives cytotoxic ROS production. This circuit lies dormant in healthy cells but is triggered by pathogenic insults and could therefore represent a safe therapeutic target for PD and other ROS-linked diseases. [ABSTRACT FROM AUTHOR]

Purpose: To demonstrate and evaluate factors contributing to near-cures in patients with Gadolinium Deposition Disease (GDD) undergoing intravenous (IV) DTPA chelation. Methods: Patients who had undergone or are currently undergoing DTPA chelation for GDD were included in this report based on their medical records that showed their perceived improvement was at least 80% back to normal. A surveywas developed that included factors commonly reported by patients treated in one clinic to determine if these 'near-cured' (pre-MRI baseline health) individuals possessed certain factors and lacked others. The anonymized survey was emailed to these individuals by the principal treating physician, the only investigator not blinded to the subjects. This report describes clinical documentation of patient status and their underlying factors in individuals treated by the primary author, and no research was performed. The survey was sent to sixteen individuals; Fourteen patients completed it (10 females; 41.1 ± 11.2 y/o). Results: The most common factor was the administration of ≤5 lifetime doses of a Gadolinium-Based Contrast Agents (GBCA) (12/14). Unconfounded agents triggering GDD were seen in nine subjects. Most subjects (12/14) initiated chelation in the first year after the causative GBCA, and most (11/14) underwent ≤10 chelations with DTPA. Good healthcare status prior to MRI was observed in 5 subjects. The majority (11/14) described their immune status as strong. Severe physical disability prior to chelation was seen in 1. Conclusion: Subjects with GDD can experience near-cure with IV DTPA chelation. Factors surveyed that predict near-cure include the start of chelation in the first year, few GBCA administrations, and good health status before MRI with GBCA injection. Nonetheless, a few patients with predictors of less successful outcomes still experienced near-cure. [ABSTRACT FROM AUTHOR]

In acidic paddy fields of South China, rice (Oryza sativa L.) faces the dual challenges of cadmium (Cd) toxicity and silicon (Si) deficiency. Although previous studies have highlighted the functions of Si application timing and strategies in mitigating Cd-stressed rice, the precise mechanisms underlying the health restoration of Cd-toxic rice and the assurance of grain safety remain elusive. This study explored Cd translocation and detoxification in the shoots of rice regulated by various Si fertilization regimes: Si(T) (all Si added before transplanting), Si(J) (all Si added at jointing), and Si(TJ) (half Si added both before transplanting and at jointing). The findings revealed that the regime of Si(TJ) was more beneficial to rice health and grain safety than Si(T) and Si(J). The osmotic regulators such as proline, soluble sugars, and soluble proteins were significantly boosted by Si(TJ) compared to other Si treatments, and which enhanced membrane integrity, balanced intracellular pH, and increased Cd tolerance of rice. Furthermore, Si(TJ) was more effective than Si(T) and Si(J) on the Cd sequestration in the cell wall, Cd bio-passivation, and the down-regulated expression of the Cd transport genes. The concentrations of Cd in the xylem and phloem treated with Si(TJ) were reduced significantly. Additionally, Si(TJ) facilitated much more Cd bound with the outer layer proteins of grains, and promoted Cd chelation and complexation by phytic acid, phenolics, and flavonoids. Overall, Si (TJ) outperformed Si(T) and Si(J) in harmonizing the phycological processes, inhibiting Cd translocation, and enhancing Cd detoxification in rice plant. Thereby the split Si application strategy offers potential for reducing Cd toxicity in rice grain. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Lactoferrin is widely found in milk and has the ability to bind iron. Previous studies have reported that lactoferrin was effective in the prevention and treatment of acute alcohol-induced liver injury (AALI). Ferroptosis is a recently discovered cell death and is involved in the development of AALI. However, the potential role of lactoferrin in acute alcohol-induced ferroptosis is still unclear. In this study, we observed that lactoferrin (10, 20, and 40 μg/mL) significantly mitigated alcohol (300 m M)-induced injury in vitro. Additionally, lactoferrin (100 and 200 mg/kg BW) significantly alleviated alcohol (4.8 g/kg BW)-induced injury in vivo. Our results showed that lactoferrin inhibited alcohol-induced upregulation of the ferroptosis marker protein ACSL4 and downregulation of GPX4. Meanwhile, lactoferrin treatment successfully reversed the elevated malondialdehyde (MDA) levels and the reduced glutathione (GSH) levels caused by alcohol treatment. These results may indicate that lactoferrin significantly decreased ferroptosis in vivo and in vitro. Lactoferrin has the potential to chelate iron, and our results showed that lactoferrin (20 μg/mL) significantly reduced iron ions and the expression of the ferritin heavy chain (FTH) under FeCl 3 (100 μ M) treatment. It was demonstrated that lactoferrin had a significant iron-chelating effect and reduced iron overload caused by FeCl 3 in AML12 cells. Next, we examined iron content and the expression of iron metabolism marker proteins transferrin receptor (TFR), divalent metal transporter 1 (DMT1), FTH, and ferroportin (FPN). Our results showed that lactoferrin alleviated iron overload induced by acute alcohol. The expression of TFR and DMT1 was downregulated, and FPN and FTH were upregulated after lactoferrin treatment in vivo and in vitro. Above all, the study suggested that lactoferrin can alleviate AALI by mitigating acute alcohol-induced ferroptosis. Lactoferrin may offer new strategies for the prevention or treatment of AALI. [ABSTRACT FROM AUTHOR]

Extrafibrillar demineralization is considered to be an ideal solution for addressing the durability of resin-dentin bonding interfaces. However, its theoretical basis is contradictory to ionization equilibrium of hydroxyapatite dissolution. In this study, various calcium chelators were selected as dentin conditioners to explore the essence of dentin demineralization with chelators and its effect on resin-dentin adhesion. Polyethyleneimine grafted with EDTA and polyacrylic acid sodium (PAAN 450k) larger than 40 kDa, as well as PAAN (PAAN 3k) and EDTA smaller than 6 kDa, were prepared as dentin conditioners. The dentin powder was designed to characterize whether it would demineralize without contact with PAAN 450k. Dentin demineralization effect with four conditioners was evaluated with field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, atomic force microscopy and quantification of hydroxyproline concentration after enzymatic degradation. Micro-tensile bond strength (µTBS) test and failure mode analysis were employed to assess the bonding effect of the four chelators in both wet and dry bonding, with H 3 PO 4 wet bonding serving as the control group. Demineralization occurs when PAAN 450k was not in direct contact with the dentin powder. The extrafibrillar demineralization cannot be induced by any chelator regardless of its molecular weight. Complete demineralization including extrafibrillar and intrafibrillar demineralization would occur with sufficient interaction time. Moreover, chelators could not provide a reliable dentin bonding effect under a short interaction time. From the perspective of theory and application, extrafibrillar demineralization is not a reliable strategy, which provides a reminder for exploring new strategies in the future. • Application of chelators to dentin does not cause extrafibrillar demineralization. • Occurrence of demineralization will ultimately cause intrafibrillar demineralization. • Calcium chelators have limited demineralization and act as mild dentin conditioners. Extrafibrillar demineralization cannot provide reliable dentin adhesion. [ABSTRACT FROM AUTHOR]

The choice of dialysate buffer in hemodialysis is crucial, with acetate being widely used despite complications. Citrate has emerged as an alternative because of its favorable effects, yet concerns persist about its impact on calcium and magnesium levels. This study investigates the influence of citrate dialysates (CDs) with and without additional magnesium supplementation on CKD-MBD biomarkers and assesses their ability to chelate divalent metals compared to acetate dialysates (ADs). A prospective crossover study was conducted in a single center, involving patients on thrice-weekly online hemodiafiltration (HDF). The following four dialysates were compared: two acetate-based and two citrate-based. Calcium, magnesium, iPTH, iron, selenium, cadmium, copper, zinc, BUN, albumin, creatinine, bicarbonate, and pH were monitored before and after each dialysis session. Seventy-two HDF sessions were performed on eighteen patients. The CDs showed stability in iPTH levels and reduced post-dialysis total calcium, with no significant increase in adverse events. Magnesium supplementation with CDs prevented hypomagnesemia. However, no significant differences among dialysates were observed in the chelation of other divalent metals. CDs, particularly with higher magnesium concentrations, offer promising benefits, including prevention of hypomagnesemia and stabilization of CKD-MBD parameters, suggesting citrate as a viable alternative to acetate. Further studies are warranted to elucidate long-term outcomes and optimize dialysate formulations. Until then, given our results, we recommend that when a CD is used, it should be used with a 0.75 mmol/L Mg concentration rather than a 0.5 mmol/L one. [ABSTRACT FROM AUTHOR]

Phytoremediation is a technique for reducing or stabilizing hazardous chemicals in polluted soil or ground water. There is a loss of agricultural products and a degradation in food quality as a result of abiotic stresses, such as those generated by heavy metals and pesticides that have an effect on plants. These toxic compounds are extensively employed in agriculture, and they have a significant influence on both human health and agricultural output. The accumulation of these toxic, persistent, and poorly biodegradable compounds causes soil and ecological disparities. PGRs, or plant growth regulators, are an appealing possibility for increasing the efficacy of phytoremediation. Plant growth-promoting rhizobacteria (PGPR), a ubiquitous root microbiome, is widely used as a biocontrol agent. They have the ability to improve plant growth by colonizing plant roots, which can benefit the plant. Several PGPRs, including P. aeruginosa, B.gladioli, and P.pseudoalcali, have been shown to be resistant to biotic and abiotic stressors. Because of their ability to digest xenobiotic chemicals, plant growth-promoting rhizobacteria (PGPR) are a promising candidate for use in the phytoremediation process. Microorganisms inhabiting the rhizosphere participate in plant resistance mechanisms by secreting and generating a variety of important compounds such as siderophores, phytohormones, and metal-binding proteins. Rhizobacteria play an important role in phytoremediation of pesticide- and heavy metal-polluted soil by decomposing toxicants and promoting plant development via mechanisms such as chelation, acidification, and phosphate solubilization. Plant growth regulators (PGRs) increase plant biomass while reducing the negative impacts of contaminants and boosting growth in harsh settings. The use of certain PGRs as exogenous treatments have also been investigated as a potential way to improving crop stress tolerance; however the efficiency varies depending on the specific stress and plant type. Several plant growth regulators, such as brassinosteroids, melatonin, strigolactones, and others, have been proven to be useful in overcoming abiotic stress. The current review focuses on the utilization of PGRs and PGPRs in phytoremediation of heavy metal and pesticide-polluted soils. [ABSTRACT FROM AUTHOR]

Multiple studies indicate that iron chelators enhance their anti-cancer properties by inducing NDRG1, a known tumor and metastasis suppressor. However, the exact role of NDRG1 remains controversial, as newer studies have shown that NDRG1 can also act as an oncogene. Our group recently introduced mitochondrially targeted iron chelators deferoxamine (mitoDFO) and deferasirox (mitoDFX) as effective anti-cancer agents. In this study, we evaluated the ability of these modified chelators to induce NDRG1 and the role of NDRG1 in breast cancer. We demonstrated that both compounds specifically increase NDRG1 without inducing other NDRG family members. We have documented that the effect of mitochondrially targeted chelators is at least partially mediated by GSK3α/β, leading to phosphorylation of NDRG1 at Thr346 and to a lesser extent on Ser330. Loss of NDRG1 increases cell death induced by mitoDFX. Notably, MDA-MB-231 cells lacking NDRG1 exhibit reduced extracellular acidification rate and grow slower than parental cells, while the opposite is true for ER+ MCF7 cells. Moreover, overexpression of full-length NDRG1 and the N-terminally truncated isoform (59112) significantly reduced sensitivity towards mitoDFX in ER+ cells. Furthermore, cells overexpressing full-length NDRG1 exhibited a significantly accelerated tumor formation, while its N-terminally truncated isoforms showed significantly impaired capacity to form tumors. Thus, overexpression of full-length NDRG1 promotes tumor growth in highly aggressive triple-negative breast cancer. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI), a consequence of coronary artery occlusion, triggers the degradation of ferritin, resulting in elevated levels of free iron in the heart and thereby inducing ferroptosis. Targeting myocardial ferroptosis through the chelation of excess iron has therapeutic potential for MI treatment. However, iron chelation in post ischemic injury areas using conventional iron‐specific chelators is hindered by ineffective myocardial intracellular chelation, rapid clearance, and high systemic toxicity. A chitosan‐desferrioxamine nanosponge (CDNS) is designed by co‐crosslinking chitosan and deferoxamine through noncovalent gelation to address these challenges. This architecture facilitates direct iron chelation regardless of deferoxamine (DFO) release due to its sponge‐like porous hydrogel structure. Upon cellular internalization, CDNS can effectively chelate cellular iron and facilitate the efflux of captured iron, thereby inhibiting ferroptosis and associated oxidative stress and lipid peroxidation. In MI mouse models, myocardial injection of CDNS promotes sustainable retention and the suppression of ferroptosis in the infarcted heart. This intervention improves cardiac function and alleviates adverse cardiac remodeling post‐MI, leading to decreased oxidative stress and the promotion of angiogenesis due to ferroptosis inhibition by CDNS in the infarcted heart. This study reveals a nanosponge‐based nanomedicine targeting myocardial ferroptosis with efficient iron chelation and efflux, offering a promising MI treatment. [ABSTRACT FROM AUTHOR]

This study explores the potential of halophytes, plants adapted to saline environments, as a novel source for developing herbal MRI contrast agents. Halophytes naturally accumulate various metals within their tissues. These metal ions, potentially complexed with organic molecules, are released into aqueous solutions prepared from the plants. We investigated the ability of these compounds to generate contrast enhancement in MRI using a sequential approach. First, aqueous extracts were prepared from seven selected halophytes, and their capacity to induce contrast in MR images was evaluated. Based on these initial findings, sample halophytes were chosen for further investigations. Second, chemical analysis revealed aluminum as the primary potent metal which enhances the contrast. Third, the halophyte extract was fractionated based on polarity, and the most polar fraction exhibited the strongest contrast‐generating effect. Finally, the relaxivity of this fraction, a key parameter for MRI contrast agents, was measured. We propose that aluminum, likely complexed with a polar molecule within the plant extract, is responsible for the observed contrast enhancement in MRI. [ABSTRACT FROM AUTHOR]

Herein, a new template carbonization method is used to prepare calcite‐type nano‐calcium carbonate (CaCO3) with a core–shell structure using calcium hydroxide as a solute and Pluronic F‐127 as a templating and pore‐forming agent. Dopamine hydrochloride is added to control the size of calcium hydroxide particles. The morphology, particle size, and crystal type of CaCO3 are characterized via transmission electron microscopy, X‐ray diffraction, nanoparticle size, and zeta potentiometer. The creation of core–shell calcium carbonate nanoparticles is examined in relation to reaction circumstances (i.e., additive sequence, additive amount, and additive mixing time), carbonization temperature, liquid flow rate, and templates with varying chain lengths. Furthermore, a discussion is held regarding the formation mechanism of spherical core–shell calcium carbonate that is created using the innovative template carbonization method. The results show that the order, amount, liquid flow rate, and template type of additives have a significant effect on the crystal shape of calcium carbonate nanoparticles. The mixing time of additives has a significant effect on the particle size of calcium carbonate nanoparticles. Interestingly, the thickness of the shell depends on the carbonization temperature, and too slow or too fast flow rate will lead to the formation of cyclic calcium carbonate nanoparticles. [ABSTRACT FROM AUTHOR]

Nature has been a rich source of pharmaceutical compounds, producing 80% of our currently prescribed drugs. The feijoa plant, Acca sellowiana , is classified in the family Myrtaceae, native to South America, and currently grown worldwide to produce feijoa fruit. Feijoa is a rich source of bioactive compounds with anticancer, anti-inflammatory, antibacterial, and antifungal activities; however, the mechanism of action of these compounds is largely not known. Here, we used chemical genetic analyses in the model organism Saccharomyces cerevisiae to investigate the mechanism of action of a feijoa-derived ethanol adduct of vescalagin (EtOH-vescalagin). Genome-wide barcode sequencing analysis revealed yeast strains lacking genes in iron metabolism, zinc metabolism, retromer function, or mitochondrial function were hypersensitive to 0.3 µM EtOH-vescalagin. This treatment increased expression of iron uptake proteins at the plasma membrane, which was a compensatory response to reduced intracellular iron. Likewise, EtOH-vescalagin increased expression of the Cot1 protein in the vacuolar membrane that transports zinc into the vacuole to prevent cytoplasmic accumulation of zinc. Each individual subunit in the retromer complex was required for the iron homeostatic mechanism of EtOH-vescalagin, while only the cargo recognition component in the retromer complex was required for the zinc homeostatic mechanism. Overexpression of either retromer subunits or high-affinity iron transporters suppressed EtOH-vescalagin bioactivity in a zinc-replete condition, while overexpression of only retromer subunits increased EtOH-vescalagin bioactivity in a zinc-deficient condition. Together, these results indicate that EtOH-vescalagin bioactivity begins with extracellular iron chelation and proceeds with intracellular transport of zinc via the retromer complex. More broadly, this is the first report of a bioactive compound to further characterize the poorly understood interaction between zinc metabolism and retromer function. [ABSTRACT FROM AUTHOR]

Herein, an affordable strategy was developed to form Pd@SiO2 nanostructure assembled onto monolithic AlOOH/Al nanoarrays from nano- to macro-scale by a one-step reaction process. (3-Aminopropyl)trimethoxysilane (APTMS) was employed as a dual-role reagent for the bidirectional bridging between Pd2+ and AlOOH/Al, as well as the formation of SiO2 matrix and mesopores. The effects of one-step organization conditions on the preparation process, catalyst structure, and catalytic performance were all studied. High hydroxyl contents in Al-based nanoarrays promoted the silanization reaction of APTMS deposition, resulting in a well-formed SiO2 shell and abundant mesopores during the thermal decomposition of APTMS. APTMS amount was not only related to SiO2 loading and encapsulation effect of the core–shell structure, but also affected Pd accessibility. Such proposed APTMS-assisted protocol for the in-situ organization of monolithic Pd@SiO2 catalysts can effectively prevent the growth and aggregation of Pd NPs, thereby favoring low-temperature activity and stability for CH4 combustion. Monolithic Pd@SiO2 catalysts supported on AlOOH/Al nanoarrays were successfully fabricated from nano- to macro-scale in one step for improved thermal stability of CH4 combustion. The cost-effective coupling agent (APTMS) acted as the bidirectional bridging between –NH2 of APTMS and Pd2+ through preferential chelation, as well as a silanization reaction between methoxy groups of APTMS and surface –OH groups on AlOOH nanoarrays to form Al–O–Si bonds. [ABSTRACT FROM AUTHOR]

Context: Given the diverse pathophysiological mechanisms underlying Alzheimer's disease, it is improbable that a single targeted drug will prove successful as a therapeutic strategy. Therefore, exploring various hypotheses in drug design is imperative. The sequestration of Fe(II) and Zn(II) cations stands out as a crucial mechanism based on the mitigation of reactive oxygen species. Moreover, inhibiting acetylcholinesterase represents a pivotal strategy to enhance acetylcholine levels in the synaptic cleft. This research aims to investigate the analogs of Huperzine A, documented in scientific literature, considering of these two hypotheses. Consequently, the speciation chemistry of these structures with Fe(II) and Zn(II) was scrutinized using quantum chemistry calculations, molecular docking simulations, and theoretical predictions of pharmacokinetics properties. From the pharmacokinetic properties, only two analogs, HupA-A1 and HupA-A2, exhibited a theoretical permeability across the blood-brain barrier; on the other hand, from a thermodynamic standpoint, the enantiomers of HupA-A2 showed negligible chelation values. The enantiomers with the most favorable interaction parameters were S′R′HupA-A1 (ΔGBIND = −40.0 kcal mol−1, fitness score = 35.5) and R′R′HupA-A1 (ΔGBIND = −35.5 kcal mol−1, fitness score = 22.61), being compared with HupA (ΔGBIND = −41.75 kcal mol−1, fitness score = 39.95). From this study, some prime candidates for promising drug were S′R′HupA-A1 and R′R′HupA-A1, primarily owing to their favorable thermodynamic chelating capability and potential anticholinesterase mechanism. Methods: Quantum chemistry calculations were carried out at B3LYP/6-31G(d) level, considering the IEF-PCM(UFF) implicit solvent model for water. The coordination compounds were assessed using the Gibbs free energy variation and hard and soft acid theory. Molecular docking calculations were conducted using the GOLD program, based on the crystal structure of the acetylcholinesterase protein (PDB code = 4EY5), where the ChemScore function was employed with the active site defined as the region within a 15-Å radius around the centroid coordinates (X = −9.557583, Y = −43.910473, Z = 31.466687). Pharmacokinetic properties were predicted using SwissADME, focusing on Lipinski's rule of five. [ABSTRACT FROM AUTHOR]

Corn peptide-iron chelates serve a dual purpose, enhancing the utilization of corn peptides while also offering a novel approach for the development of iron supplements. To examine the structural properties and thermal stability of corn peptide-iron chelates, samples of this compound were prepared from corn peptides and ferrous chloride. Following ultraviolet spectroscopy and thermogravimetric analysis, the binding sites of the identified corn peptide fragments and ferrous ions were simulated by molecular docking. The stability of the corn peptide-iron chelate was observed at different temperatures and pH values, as well as under different in vitro digestion conditions. The results showed that the ultraviolet absorption peak changed. More specifically, the characteristic absorption peak shifted from 274.99 nm to 275.01 nm. Moreover, the corn peptide and corn peptide-iron chelate were compared and found to differ in a number of their properties. Thermogravimetric analysis revealed residual rates of 34.94% and 18.74% for corn chelate and peptide, respectively, while thermal stability of the corn peptide-iron chelate was found to be significantly higher that of the corn peptide. The binding energy levels of FSAASYPDLIDALP and LQQRQQLLNPL with Fe2+ were -50.50 and -48.61 kJ/mol, respectively, and the amino group of Asp8 (aspartic acid) was found to provide the ligand site. In addition, Pro7 (proline), Ser5 (serine), Tyr6 (tyrosine), and Leu7 (leucine) were found to bind to the ferrous ions to form hydrophobic interactions. The relative molecular masses were mostly below 1 000 u under the action of different temperatures. In addition, small peptides were more easily chelated and absorbed, and were stable under relatively alkaline conditions. [ABSTRACT FROM AUTHOR]

The synthesis of eight Ru(II) and Os(II) photosensitizers bearing a common 9,10-disubstituted-1,4,5,8-tetraazaphenanthrene backbone is reported. With Os(II) photosensitizers, the 9,10-diNH2-1,4,5,8-tetraazaphenanthrene could be directly chelated onto the metal center via the heteroaromatic moiety, whereas similar conditions using Ru(II) resulted in the formation of an o-quinonediimine derivative. Hence, an alternative route, proceeding via the chelation of 9-NH2-10-NO2-1,4,5,8-tetraazaphenanthrene and subsequent ligand reduction of the corresponding photosensitizers was developed. Photosensitizers chelated via the polypyridyl-type moiety exhibited classical photophysical properties whereas the o-quinonediimine chelated Ru(II) analogues exhibited red-shifted absorption (520 nm) and no photoluminescence at room temperature in acetonitrile. The most promising photosensitizers were investigated for excited-state quenching with guanosine-5′-monophosphate in aqueous buffered conditions where reductive excited-state electron transfer was observed by nanosecond transient absorption spectroscopy. [ABSTRACT FROM AUTHOR]

The intricate process of neuronal differentiation integrates multiple signals to induce transcriptional, morphological, and electrophysiological changes that reshape the properties of neural precursor cells during their maturation and migration process. An increasing number of neurotransmitters and biomolecules have been identified as molecular signals that trigger and guide this process. In this sense, taurine, a sulfur-containing, non-essential amino acid widely expressed in the mammal brain, modulates the neuronal differentiation process. In this study, we describe the effect of taurine acting via the ionotropic GABAA receptor and the metabotropic GABAB receptor on the neuronal differentiation and electrophysiological properties of precursor cells derived from the subventricular zone of the mouse brain. Taurine stimulates the number of neurites and favors the dendritic complexity of the neural precursor cells, accompanied by changes in the somatic input resistance and the strength of inward and outward membranal currents. At the pharmacological level, the blockade of GABAA receptors inhibits these effects, whereas the stimulation of GABAB receptors has no positive effects on the taurine-mediated differentiation process. Strikingly, the blockade of the GABAB receptor with CGP533737 stimulates neurite outgrowth, dendritic complexity, and membranal current kinetics of neural precursor cells. The effects of taurine on the differentiation process involve Ca2+ mobilization and the activation of intracellular signaling cascades since chelation of intracellular calcium with BAPTA-AM, and inhibition of the CaMKII, ERK1/2, and Src kinase inhibits the neurite outgrowth of neural precursor cells of the subventricular zone. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed dual C–H functionalization of substituted aromatic ketones and ester with maleimides leading to tricyclic heterocyclic molecules with good to excellent yield is reported. In this protocol, weak chelation of the carbonyl groups has been successfully utilized for the selective activation of the ortho-methyl C(sp3)–H bond instead of the ortho-C(sp2)–H bond in the presence of an external bidentate ligand Ac-Ile-OH. The reaction proceeds through two-fold C–H activation to generate a five-membered cyclic ring. The first C–H activation takes place selectively at the benzylic position followed by a second C–H bond activation at the meta position. The protocol demonstrates compatibility among diverse substituted aromatic ketones and ester as well as various substituted maleimides. Further derivatization of the tricyclic ketone to an alcohol exhibits the synthetic applicability of the protocol. Also, a plausible reaction mechanism has been proposed. [ABSTRACT FROM AUTHOR]

A titanium-mediated aza-BODIPY synthesis using diketopyrrolopyrrole bearing o-anisyl substituents provided B,O-chelated pyrrolopyrrole aza-BODIPYs in a one-pot manner via ether bond cleavage and chelation of the resulting nucleophilic oxygen to the boron atom. The B,O-chelation not only induces the redshifts of absorption and fluorescence but also endows chiroptical properties. [ABSTRACT FROM AUTHOR]