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Polyoxometalates (POMs) are metal-oxygen clusters composed of {MO6} octahedra that have attracted considerable attention due to their remarkable antiviral, antibacterial and antitumor activities. Despite their potential, the molecular mechanisms underlying their cellular toxicity remain poorly understood. This study investigates how Anderson-Evans type polyoxotungstates (POTs) and polyoxomolybdates (POMos) interact with biological membranes by examining their effects on the zeta (ζ) – potential of the lipid bilayer and the size of small unilamellar liposomes of different phospholipid compositions. POTs affected the ζ-potential of neutral (1,2-dioleoyl-sn-glycero-3-phosphocholine, DOPC) and slightly negatively charged (1,2-dioleoyl-sn-glycero-3-phosphoethanolamine; DOPC:DOPE) membranes in the order [MnW6O24]8– > [Ni(OH)6W6O18]4– > [TeW6O24]6–. The addition of negatively charged cardiolipin (CL) to DOPC reduced the interaction of POTs with the membrane. An opposite effect was observed for POMos, which changed the ζ-potential of neutral and slightly negatively charged membranes in the order [Al(OH)6Mo6O18]3– > [Cr(OH)6Mo6O18]3– >> [Ni(OH)6Mo6O18]4–. The addition of POMos increased the size of the liposomes in reverse order. The binding of [Al(OH)6Mo6O18]3– to the PE-containing phospholipid membranes and the effect of ionic strength on the interaction of [Cr(OH)6Mo6O18]3– with DOPC:CL liposomes could be inhibited by potassium fluoride (KF). Interestingly, KF did not inhibit the interaction of other POMos with membranes as indicated by ζ-potential measurements. These results suggest that the interaction of Anderson-Evans type POMs with phospholipid membranes is influenced more by their addenda and central ions than by their total charge. By unravelling the structure-activity relationships for the different POMs, we contribute to the design of biologically active POMs for therapeutic use.

This study investigates the concentration-dependent speciation and stability of Keggin-type [PVWVI12O40]3–(PW12) and Wells-Dawson type [α-PV2WVI18O62]6–(P2W18) polyoxotungstates across the pH range from two to eight and buffer systems including acetic acid-sodium acetate, citric acid-sodium citrate, sodium phosphate, Tris-HCl and HEPES. Utilizing 31P Nuclear Magnetic Resonance spectroscopy for detailed analysis, we quantified the stability and hydrolysis patterns of PW12 and P2W18 in various buffer solutions at concentrations of 3, and 15 mM, and compared with previously published data for 10 mM solutions. Our research shows that higher concentrations of PW12 and P2W18 in solutions improve their stability in neutral to moderately alkaline environments (pH seven and above), making them less prone to hydrolysis. This pronounced effect underscores the crucial role of concentration in optimizing the behavior of polyoxometalates under varying pH levels, revealing a strong link between concentration and stability across various buffers and highlighting how ionic strength, buffer composition, and pH crucially interact to influence POM stability. Research on how ionic strength affects the speciation of 3 mM solutions shows that the stability of P2W18 decreases as the pH approaches neutrality and as ionic strength increases, indicating heightened hydrolysis and reduced stability. For the inherently less stable PW12, the findings indicate a shift in hydrolysis pathways—different concentrations of the hydrolysis products, a change likely driven by the increased ionic strength. These findings emphatically underscore the critical importance of meticulously selecting the right buffer and concentration to fully unlock the potential of polyoxometalates such as PW12 and P2W18. Strategic choices are essential for leveraging these compounds as pivotal elements in groundbreaking applications, poised to revolutionize scientific and technological landscapes.

Early-life exposure to natural and synthetic chemicals can impact acute and chronic health conditions. Here, a suspect screening workflow anchored on high-resolution mass spectrometry was applied to elucidate xenobiotics in breast milk and matching stool samples collected from Nigerian mother-infant pairs (n = 11) at three time points. Potential correlations between xenobiotic exposure and the developing gut microbiome, as determined by 16S rRNA gene amplicon sequencing, were subsequently explored. Overall, 12,192 and 16,461 features were acquired in the breast milk and stool samples, respectively. Following quality control and suspect screening, 562 and 864 features remained, respectively, with 149 of these features present in both matrices. Taking advantage of 242 authentic reference standards measured for confirmatory purposes of food bio-actives and toxicants, 34 features in breast milk and 68 features in stool were identified and semi-quantified. Moreover, 51 and 78 features were annotated with spectral library matching, as well as 416 and 652 by in silico fragmentation tools in breast milk and stool, respectively. The analytical workflow proved its versatility to simultaneously determine a diverse panel of chemical classes including mycotoxins, endocrine-disrupting chemicals (EDCs), antibiotics, plasticizers, perfluorinated alkylated substances (PFAS), and pesticides, although it was originally optimized for polyphenols. Spearman rank correlation of the identified features revealed significant correlations between chemicals of the same classification such as polyphenols. One-way ANOVA and differential abundance analysis of the data obtained from stool samples revealed that molecules of plant-based origin elevated as complementary foods were introduced to the infants’ diets. Annotated compounds in the stool, such as tricetin, positively correlated with the genus Blautia. Moreover, vulgaxanthin negatively correlated with Escherichia-Shigella. Despite the limited sample size, this exploratory study provides high-quality exposure data of matched biospecimens obtained from mother-infant pairs in sub-Saharan Africa and shows potential correlations between the chemical exposome and the gut microbiome.

Reticular and cluster materials often feature complex formulas, making a comprehensive overview challenging due to the need to consult various resources. While datasets have been collected for metal-organic frameworks (MOFs), covalent organic frameworks (COFs), and zeolites, among others, there remains a gap in systematically organized information for polyoxometalates. This paper introduces a carefully curated dataset of 1984 polyoxometalate (POM) and related cluster metal oxide formula instances, currently connecting over 2500 POM material instances. These POM instances incorporate 75 different chemical elements, with compositions ranging from binary to octonary element clusters. This dataset not only enhances accessibility to polyoxometalate data but also aims to facilitate further research and development in the study of these complex inorganic compounds.

Accurate measurement of testicular volume (TV) in boys is an important tool in clinical practice, e.g., in varicocele treatment. This study aims to assess the degree of intra- and interobserver variability of testicular volume measurements. In a prospective study, boys between 11 and 17 years of age without testicular pathology were enrolled. Testicular ultrasound was performed by three investigators (A: pediatric radiologist; B: pediatric surgery/urology resident; C: pediatric urologist). Intraobserver variability was calculated in investigators B and C and interobserver variability between all three investigators. A total of 30 boys were enrolled. Mean intraobserver variability in both observers was +0.3% with a range of −39.6 to 51.5%. The proportion of measurements with a difference >20% was 18.6%. The mean interobserver variability was −1.0% (range: −74.1% to 62.8%). The overall proportion of measurements with a difference >20% was 35%. A lower testicular size of < 4 mL showed a significantly higher rate of >20% difference in both the intraobserver group (31.1% vs. 14.4%; p = 0.035) and the interobserver group (63.2% vs. 26.2%; p = 0.000031). Furthermore, the rate of >20% difference was significantly lower in obese compared to non-obese patients in both the intraobserver (2.8% vs. 22.4%; p = 0.0084) and the interobserver group (24% vs. 40.8%, p = 0.0427). Both intraobserver and interobserver variability in ultrasound-based TV measurements in pubertal boys contain a relevant degree of uncertainty that renders them unsuitable for individualized follow-up care. At the cohort level, however, mean differences in ultrasound-based TV measurements are low enough to make ultrasound comparisons reasonable.

Key Clinical Message Airway management in children can be challenging. A hybrid technique using a video laryngoscope‐assisted flexible bronchoscopic nasotracheal intubation allowed a successful airway management in a two‐year‐old child with a large tongue tumor.

Abstract The “dragon-eye” fruits produced by the tropical longan tree are rich in nutrients and antioxidants. They suffer from post-harvest enzymatic browning, a process for which mainly the polyphenol oxidase (PPO) family of enzymes is responsible. In this study, two cDNAs encoding the PPO have been cloned from leaves of Dimocarpus longan (Dl), heterologously expressed in Escherichia coli and purified by affinity chromatography. The prepro-DlPPO1 contains two signal peptides at its N-terminal end that facilitate transportation of the protein into the chloroplast stroma and to the thylakoid lumen. Removal of the two signal peptides from prepro-DlPPO1 yields pro-DlPPO1. The prepro-DlPPO1 exhibited higher thermal tolerance than pro-DlPPO1 (unfolding at 65 °C vs. 40 °C), suggesting that the signal peptide may stabilize the fold of DlPPO1. DlPPO1 can be classified as a tyrosinase because it accepts both monophenolic and diphenolic substrates. The pro-DlPPO1 exhibited the highest specificity towards the natural diphenol (–)-epicatechin (kcat/KM of 800 ± 120 s−1 mM−1), which is higher than for 4-methylcatechol (590 ± 99 s−1 mM−1), pyrogallol (70 ± 9.7 s−1 mM−1) and caffeic acid (4.3 ± 0.72 s−1 mM−1). The kinetic efficiencies of prepro-DlPPO1 are 23, 36, 1.7 and 4.7-fold lower, respectively, than those observed with pro-DlPPO1 for the four aforementioned diphenolic substrates. Additionally, docking studies showed that (–)-epicatechin has a lower binding energy than any other investigated substrate. Both kinetic and in-silico studies strongly suggest that (–)-epicatechin is a good substrate of DlPPO1 and ascertain the affinity of PPOs towards specific flavonoid compounds.

The title polyoxometalate-based organic–inorganic hybrid compound, [Na6(C3H10NO2)4][W12O40(OH)2]·10H2O, consists of a di-μ3-hydroxido-tetra-μ3-oxido-octadeca-μ-oxido-octadecaoxidododecatungstate (paradodecatungstate B) anion, [W12O40(OH)2]10–, and six sodium cations coordinated by the oxygen ions of the polyanions, serinol ligands protonated at the N atom, and water molecules. The centrosymmetric paratungstate B anion shows characteristic features in terms of bond lengths and angles. The three-dimensional framework structure is established by bonding of the sodium cations with oxygen ions of the paratungstate B anions and a network consisting of N—H...O and O—H...O hydrogen bonds of medium strength between the protonated serinol cations, water molecules and the paratungstate B anions. The title compound was also characterized by means of elemental analysis, IR spectroscopy and thermogravimetric analysis.

This study investigates the crucial factors influencing the end-systolic and end-diastolic volumes in MRI volumetry and their direct effects on the derived functional parameters. Through the simultaneous acquisition of 2D-cine and 3D whole-heart slices in end-diastole and end-systole, we present a novel direct comparison of the volumetric measurements from both methods. A prospective study was conducted with 18 healthy participants. Both 2D-cine and 3D whole-heart sequences were obtained. Despite the differences in the creation of 3D volumes and trigger points, the impact on the LV volume was minimal (134.9 mL ± 16.9 mL vs. 136.6 mL ± 16.6 mL, p < 0.01 for end-diastole; 50.6 mL ± 11.0 mL vs. 51.6 mL ± 11.2 mL, p = 0.03 for end-systole). In our healthy patient cohort, a systematic underestimation of the end-systolic volume resulted in a significant overestimation of the SV (5.6 mL ± 2.6 mL, p < 0.01). The functional calculations from the 3D whole-heart method proved to be highly accurate and correlated well with function measurements from the phase-contrast sequences. Our study is the first to demonstrate the superiority of 3D whole-heart volumetry over 2D-cine volumetry and sheds light on the systematic error inherent in 2D-cine measurements.

Abstract In order to elucidate the active polyoxotungstate (POT) species that inhibit fungal polyphenol oxidase (AbPPO4) in sodium citrate buffer at pH 6.8, four Wells–Dawson phosphotungstates [α/β-PV 2WVI 18O62]6− (intact form), [α 2 -PV 2WVI 17O61]10− (monolacunary), [PV 2WVI 15O56]12− (trilacunary) and [H2PV 2WVI 12O48]12− (hexalacunary) were investigated. The speciation of the POT solutions under the dopachrome assay (50 mM Na-citrate buffer, pH 6.8; L-3,4−dihydroxyphenylalanine as a substrate) conditions were determined by 183W-NMR, 31P-NMR spectroscopy and mass spectrometry. The intact Wells–Dawson POT [α/β-PV 2WVI 18O62]6− shows partial (~ 69%) disintegration into the monolacunary [α 2 -PV 2WVI 17O61]10− anion with moderate activity (K i = 9.7 mM). The monolacunary [α 2 -PV 2WVI 17O61]10− retains its structural integrity and exhibits the strongest inhibition of AbPPO4 (K i = 6.5 mM). The trilacunary POT [PV 2WVI 15O56]12− rearranges to the more stable monolacunary [α 2 -PV 2WVI 17O61]10− (~ 62%) accompanied by release of free phosphates and shows the weakest inhibition (K i = 13.6 mM). The hexalacunary anion [H2PV 2WVI 12O48]12− undergoes time-dependent hydrolysis resulting in a mixture of [H2PV 2WVI 12O48]12−, [PV 8WVI 48O184]40−, [PV 2WVI 19O69(H2O)]14− and [α 2 -PV 2WVI 17O61]10− which together leads to comparable inhibitory activity (K i = 7.5 mM) after 48 h. For the solutions of [α/β-PV 2WVI 18O62]6−, [α 2 -PV 2WVI 17O61]10− and [PV 2WVI 15O56]12− the inhibitory activity is correlated to the degree of their rearrangement to [α 2 -PV 2WVI 17O61]10−. The rearrangement of hexalacunary [H2PV 2WVI 12O48]12− into at least four POTs with a negligible amount of monolacunary anion interferes with the correlation of activity to the degree of their rearrangement to [α 2 -PV 2WVI 17O61]10−. The good inhibitory effect of the Wells–Dawson [α 2 -PV 2WVI 17O61]10− anion is explained by the low charge density of its protonated forms H x [α 2 -PV 2WVI 17O61](10−x)− (x = 3 or 4) at pH 6.8.

(1) Purpose: to compare right ventricular (RV) functional parameters in children with surgically repaired congenital heart disease (CHD) using single/double breath hold (BH) and free-breathing (FB) real-time compressed sensing (CS) cine cardiac magnetic resonance (cMRI) with standard retrospective segmented multi breath hold (RMB) cine cMRI. (2) Methods: Twenty patients with CHD underwent BH and FB, as well as RMB cine cMRI, at 3T to obtain a stack of continuous axial images of the RV. Two radiologists independently performed qualitative analysis of the image quality (rated on a 5-point scale; 1 = non-diagnostic to 5 = excellent) and quantitative analysis of the RV volume measurements. (3) Results: The best image quality was provided by RMB (4.5; range 2–5) compared to BH (3.9; range 3–5; p = 0.04) and FB (3.6; range 3–5; p < 0.01). The RV functional parameters were comparable among BH, FB, and RMB with a difference of less than 5%. The scan times for BH (44 ± 38 s, p < 0.01) and FB (24 ± 7 s, p < 0.01) were significantly reduced compared to for RMB (261 ± 68 s). (4) Conclusions: CS-FB and CS-BH real-time cine cMRI in children with CHD provides diagnostic image quality with excellent accuracy for measuring RV function with a significantly reduced scan time compared to RMB.

Reticular and cluster materials often feature complex formulas, making a comprehensive overview challenging due to the need to consult various resources. While datasets have been collected for metal-organic frameworks (MOFs), covalent organic frameworks (COFs), and zeolites, among others, there remains a gap in systematically organized information for polyoxometalates. This paper introduces a carefully curated dataset of 1984 polyoxometalate (POM) and related cluster metal oxide formula instances, currently connecting over 2500 POM material instances. These POM instances incorporate 75 different chemical elements, with compositions ranging from binary to octonary element clusters. This dataset not only enhances accessibility to polyoxometalate data but also aims to facilitate further research and development in the study of these complex inorganic compounds. [ABSTRACT FROM AUTHOR]

Background: Metastatic osteosarcoma with direct cardiac involvement is an exceptionally rare finding. Reliable detection of cardiac metastases is known to be crucial for patients therapy and prognosis. Case Summary: In a 10-year-old boy affected by osteosarcoma of the left femur, a baseline Fluorine-18-fluorodeoxy-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) was performed to assess the full extent of disease. Whole-body scan detected numerous bone metastases together with a single pulmonary metastasis. Moreover, increased tracer uptake was observed in the intracavitary right cardiac ventricle in the position of a subtle spot of calcification. Because of nondetectability of a cavitary lesion on echocardiography, cardiac magnetic resonance imaging (CMRI) examination was performed to evaluate cardiac 18F-FDG PET/CT finding. CMRI revealed a small nodule in the right ventricle attached to the trabeculae, highly suspicious of a direct cardiac metastasis. After 4 cycles of chemotherapy, complete regression of tracer uptake of the lesion was observed on a follow-up 18F-FDG PET/CT scan. Conclusion: CMRI is able to detect even small, clinically asymptomatic cardiac metastases in young patients affected by osteosarcoma.

Over the course of biological evolution, approximately 25 to 30 elements have been recognized as essential for the proper functioning of biological systems since the emergence of life [...]

Achondroplasia is the most common skeletal dysplasia and is associated with serious complications such as foramen magnum stenosis (FMS). This case report describes an infant with achondroplasia who presented with a syndrome of inappropriate antidiuretic hormone secretion (SIADH), secondary to significant FMS and myelocompression. A 2-month-old boy with prenatally diagnosed achondroplasia was referred due to disordered breathing and altered consciousness. On admission, apathy, hypotonus, and hypothermia with typical features of achondroplasia were noticed. Laboratory investigations revealed severe hyponatremia and hypochloridaemia with normal glucose and urea levels. The diagnosis of SIADH was made based on low serum osmolality in the presence of high urine osmolality, along with an elevated copeptin level. An emergency computerized tomography showed a high-grade stenosis at the cranio-cervical junction; subsequent magnetic resonance imaging demonstrated myelocompression. The patient underwent decompression surgery the next day; serum osmolality increased after the operation. Spontaneous breathing after extubation was sufficient whereas tetraplegia persisted despite intensive physiotherapy. Clinicians should be aware of SIADH as a presenting sign of FMS in children with achondroplasia. Further discussion is warranted regarding improving parental education and timing of screening recommendations. [ABSTRACT FROM AUTHOR]

Accurate measurement of testicular volume (TV) in boys is an important tool in clinical practice, e.g., in varicocele treatment. This study aims to assess the degree of intra- and interobserver variability of testicular volume measurements. In a prospective study, boys between 11 and 17 years of age without testicular pathology were enrolled. Testicular ultrasound was performed by three investigators (A: pediatric radiologist; B: pediatric surgery/urology resident; C: pediatric urologist). Intraobserver variability was calculated in investigators B and C and interobserver variability between all three investigators. A total of 30 boys were enrolled. Mean intraobserver variability in both observers was +0.3% with a range of −39.6 to 51.5%. The proportion of measurements with a difference >20% was 18.6%. The mean interobserver variability was −1.0% (range: −74.1% to 62.8%). The overall proportion of measurements with a difference >20% was 35%. A lower testicular size of < 4 mL showed a significantly higher rate of >20% difference in both the intraobserver group (31.1% vs. 14.4%; p = 0.035) and the interobserver group (63.2% vs. 26.2%; p = 0.000031). Furthermore, the rate of >20% difference was significantly lower in obese compared to non-obese patients in both the intraobserver (2.8% vs. 22.4%; p = 0.0084) and the interobserver group (24% vs. 40.8%, p = 0.0427). Both intraobserver and interobserver variability in ultrasound-based TV measurements in pubertal boys contain a relevant degree of uncertainty that renders them unsuitable for individualized follow-up care. At the cohort level, however, mean differences in ultrasound-based TV measurements are low enough to make ultrasound comparisons reasonable. [ABSTRACT FROM AUTHOR]