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The online version of the original article can be found at https://doi.org/10.1186/s12877-023-03762-z. B Correction to: BMC Geriatrics (2023) 23:39 b https://doi.org/10.1186/s12877-023-03762-z After publication of this article [[1]], the authors reported that the first affiliation of the first author should be removed, leaving the second one. [Extracted from the article]

There has been considerable interest in adsorptive separation of C2H2/CH4 and CO2/CH4 gas mixtures due to its industrial significance and scientific challenge. In this work, we have designed and synthesized a bent diisophthalate ligand functionalized with aminopyrimidine groups, and constructed via a solvothermal reaction, a porous copper-based framework. Single-crystal X-ray diffraction studies show that the framework is a three-dimensional network containing three different types of polyhedral nanocages, which are stacked together to form two distinct types of one-dimensional channels along the crystallographic c axis. The compound after activation shows exceptionally high C2H2 and CO2 uptakes of 211 and 120 cm3 (STP) g−1 at 295 K and 1 atm, as well as impressive adsorption selectivities towards C2H2 and CO2 over CH4. High C2H2 and CO2 uptake capacities as well as significant adsorption selectivities of C2H2 and CO2 over CH4 imply potential applications in the adsorptive separation and purification of C2H2/CH4 and CO2/CH4 gas mixtures, which have been verified by column breakthrough experiments. Several important binding sites for C2H2 and CO2 in ZJNU-54 were revealed by quantum chemical calculations, demonstrating that the organic linkers in ZJNU-54 form unique structures that facilitate the adsorption of C2H2, while the amine groups and the Lewis basic pyrimidine-ring nitrogen sites in the organic linker improve the adsorption energies for CO2, finally leading to the increase of adsorption capacities for these two gas molecules. This work provides an efficient strategy for incorporating specific functional groups into cage-based MOFs for generating new adsorbents for highly selective gas storage and separation. [ABSTRACT FROM AUTHOR]

There has been considerable interest in adsorptive separation of C2H2/CH4 and CO2/CH4 gas mixtures due to its industrial significance and scientific challenge. In this work, we have designed and synthesized a bent diisophthalate ligand functionalized with aminopyrimidine groups, and constructed via a solvothermal reaction, a porous copper-based framework. Single-crystal X-ray diffraction studies show that the framework is a three-dimensional network containing three different types of polyhedral nanocages, which are stacked together to form two distinct types of one-dimensional channels along the crystallographic c axis. The compound after activation shows exceptionally high C2H2 and CO2 uptakes of 211 and 120 cm3 (STP) g−1 at 295 K and 1 atm, as well as impressive adsorption selectivities towards C2H2 and CO2 over CH4. High C2H2 and CO2 uptake capacities as well as significant adsorption selectivities of C2H2 and CO2 over CH4 imply potential applications in the adsorptive separation and purification of C2H2/CH4 and CO2/CH4 gas mixtures, which have been verified by column breakthrough experiments. Several important binding sites for C2H2 and CO2 in ZJNU-54 were revealed by quantum chemical calculations, demonstrating that the organic linkers in ZJNU-54 form unique structures that facilitate the adsorption of C2H2, while the amine groups and the Lewis basic pyrimidine-ring nitrogen sites in the organic linker improve the adsorption energies for CO2, finally leading to the increase of adsorption capacities for these two gas molecules. This work provides an efficient strategy for incorporating specific functional groups into cage-based MOFs for generating new adsorbents for highly selective gas storage and separation. [ABSTRACT FROM AUTHOR]

Design and synthesis of robust porous lanthanide-based metal–organic frameworks (Ln-MOFs) from flexible organic ligands is currently a formidable task to chemists. In this work, a porous Ln-MOF based on a flexible cyclotriphosphazene-functionalized organic ligand, hexakis(4-carboxylatephenoxy) cyclotriphosphazene, has been solvothermally synthesized. Single-crystal X-ray diffraction analyses show that the compound exhibits a three-dimensional structure built from rod-shaped secondary building units which are linked to each other through the organic ligands to form open frameworks with rectangular channels along the crystallographic a direction. Remarkably, although the flexible ligand was used, the Ln-MOF material after desolvation exhibited permanent porosity which has been established by various gas adsorption isotherms, displaying selective adsorption of C2 hydrocarbons over CH4 at room temperature. This work presents a rare example of a permanently porous Ln-MOF based on a flexible ligand exhibiting selective gas adsorption behaviours. [ABSTRACT FROM AUTHOR]

A new copper-based metal–organic framework [Cu2L(H2O)2]·5DMF·2H2O (ZJNU-56) has been solvothermally synthesized using a custom-designed asymmetric rigid bent diisophthalate ligand, 5,5′-(1-amine-naphthyl-2,4-diyl) diisophthalic acid (H4L), and structurally determined by single-crystal X-ray diffraction. ZJNU-56 features a three-dimensional (3D) open framework incorporating three different types of metal–organic cages and two distinct types of one-dimensional channels. With a moderate BET surface area of 1655 m2 g−1, optimized pore structure, and functional sites (open copper sites and Lewis basic amine groups) on the cage surface, ZJNU-56 after desolvation exhibits highly selectively adsorptive separation of C2H2 and CO2 over CH4 under ambient conditions. At 298 K, the predicted IAST selectivities are 35.7–72.9 for an equimolar C2H2/CH4 gas mixture and 6.8–7.0 for an equimolar CO2/CH4 gas mixture at pressures varying from 1 to 109 kPa, respectively, which are among the highest reported to date for copper-based MOFs. [ABSTRACT FROM AUTHOR]

A new copper-based metal–organic framework [Cu2L(H2O)2]·5DMF·2H2O (ZJNU-56) has been solvothermally synthesized using a custom-designed asymmetric rigid bent diisophthalate ligand, 5,5′-(1-amine-naphthyl-2,4-diyl) diisophthalic acid (H4L), and structurally determined by single-crystal X-ray diffraction. ZJNU-56 features a three-dimensional (3D) open framework incorporating three different types of metal–organic cages and two distinct types of one-dimensional channels. With a moderate BET surface area of 1655 m2 g−1, optimized pore structure, and functional sites (open copper sites and Lewis basic amine groups) on the cage surface, ZJNU-56 after desolvation exhibits highly selectively adsorptive separation of C2H2 and CO2 over CH4 under ambient conditions. At 298 K, the predicted IAST selectivities are 35.7–72.9 for an equimolar C2H2/CH4 gas mixture and 6.8–7.0 for an equimolar CO2/CH4 gas mixture at pressures varying from 1 to 109 kPa, respectively, which are among the highest reported to date for copper-based MOFs. [ABSTRACT FROM AUTHOR]

We investigated the anti-aging and redox state regulation effects by A-type proanthocyanidins (PACs)-rich cranberry concentrate (CBC) and its comparison with B-type PACs-rich grape seed extract (GSE). Using the Q-Extractive mass spectrometry, PACs dimer A and B were identified as predominant phenolic compounds of CBC and GSE, respectively, while epicatechin was present in both extracts. Using the d -galactose-induced aging mice model, effects were investigated via an 8-week oral gavage considering water-soluble vitamin E as the positive control. Both CBC and GSE reduced hepatic and brain thiobarbituric acid reactive substances, and plasma 8-isoprostane levels by 30–57%, 24–30% and 11–62%, respectively, and decreased brain and plasma monoamine oxidase activities by 27–59% and 65–71%, respectively. CBC could improve hepatic glutathione peroxidase activity by 42%, while GSE increased hepatic superoxide dismutase activity by 13%. Therefore, both extracts exerted anti-aging effects probably via regulating in vivo redox state. However, neither generated any effect on catalase activities. [ABSTRACT FROM AUTHOR]

Heterocyclic aromatic amines (HAAs) were not only present in cooked foods and cigarette smoke, but also measured in airborne particles and diesel-exhaust particles. Typical HAAs have been reported to induce carcinogenicity and metabolic disturbances, but how these hazardous compounds interfere with metabolic networks by regulating metabolic pathways and fingerprinting signature metabolites as biomarkers remains ambiguous. We developed an advanced strategy that adopted chemical isotope labeling ultrahigh-performance liquid chromatography coupled to quadrupole-Orbitrap high-resolution mass spectrometry for urinary nontargeted metabolomics analysis to gain new insight into in vivo physiological responses stimulated by exposure to typical HAAs. Rats were orally administered with a single dose of 2-amino-1-methyl-6-phenylimidazo[4,5- b ]pyridine (PhIP) or 2-amino-3,8-dimethylimidazo[4,5- f ]quinoxaline (MeIQx) (1 and 10 mg/kg bw) and their D 3 -isotopic compounds, respectively, and urine samples were then continuously collected within 36 h. Metabolomics data were acquired and processed by classical multivariate statistical analysis, while urinary metabolites were further identified and characterized according to mass spectrometric fragmentation rules, time- and dose-dependent profiles, and calibration of synthesized standards. We monitored 23 and 37 urinary metabolites as the biotransformation products of PhIP and MeIQx, respectively, and first identified demethylated metabolites of PhIP, tentatively named 2-amino-6-phenylimidazo[4,5- b ]pyridine, and dihydroxylation products of classical HAAs as short-term biomarkers of exposure to further unravel the metabolic networks. In addition, our findings revealed that both HAAs significantly disturb histidine metabolism, arginine and proline metabolism, tryptophan metabolism, pyrimidine metabolism, tricarboxylic acid cycle, etc. Furthermore, we found that histamine, methionine, alanine, and 4-guanidinobutanoic acid could be considered potential characteristic biomarkers for the oncogenicity or carcinogenicity of both PhIP and MeIQx and screened their specific key pivotal metabolites. The current metabolomics approach is applicable in mapping updated urinary metabolic fingerprints and identifying potential specific biomarkers for HAAs-induced early tumorigenesis. [Display omitted] • We firstly identified N1-demethylated biotransformation products of PhIP. • We provided updated evidence for unraveling metabolic networks of HAAs in vivo. • We innovatively mapped urinary metabolic fingerprints from the exposure to HAAs. • We discovered amino acid metabolic pathways significantly affected by HAAs. • Potential characteristic biomarkers for the carcinogenicity of HAAs were screened. [ABSTRACT FROM AUTHOR]

Perchlorate is a stable and readily transportable thyroid hormone disruptor, and prevalent exposure to perchlorate through food and drinking water has raised public concern about its health effects. The physiologically based toxicokinetic (PBTK) model as a dose prediction method is effective to predict the toxicant exposure dose of an organism and helps quantitatively assess the dose-dependent relationship with toxic effects. The current study aimed to establish a multi-compartment PBTK model based on updated time-course datasets of single oral exposure to perchlorate in rats. With adjustment of the kinetic parameters, the model fitted well the toxicokinetic characteristics of perchlorate in urine, blood, and thyroid from our experiments and the literature, and the coefficient of determination (R 2) between the fitting values and the experimental data in regression analysis was greater than 0.91, indicating the robustness of the current model. The results of sensitivity analysis and daily repeated exposure simulations together confirmed its effective renal clearance. According to the distribution characteristic of perchlorate, a correlation study of internal and external exposure was conducted using urinary perchlorate as a bioassay indicator. The developed multi-compartment model for perchlorate updates important toxicokinetic data and kinetic parameters, providing analytical and modeling tools for deriving total exposure levels in the short term. [Display omitted] • Toxicokinetic data for acute oral exposure to perchlorate in rats were supplemented. • The multi-compartment PBTK model was built and focused on urine, blood and thyroid. • Calibrated and validated model kinetic parameters and fitting ranges was extended. • Long-term daily repeated exposure simulations confirmed low accumulation. • Internal and external exposure correlation analysis was performed based on current model. [ABSTRACT FROM AUTHOR]