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Constructing three‐dimensional (3D) structural characteristics on two‐dimensional (2D) covalent organic frameworks (COFs) is a good approach to effectively improve the permeability and mass transfer rate of the materials and realize the rapid adsorption for guest molecules, while avoiding the high cost and monomer scarcity in preparing 3D COFs. Herein, we report for the first time a series of colyliform crystalline 2D COFs with quasi‐three‐dimensional (Q‐3D) topologies, consisting of unique "stereoscopic" triangular pores, large interlayer spacings and flexible constitutional units which makes the pores elastic and self‐adaptable for the guest transmission. The as‐prepared QTD‐COFs have a faster adsorption rate (2.51 g h−1) for iodine than traditional 2D COFs, with an unprecedented maximum adsorption capacity of 6.29 g g−1. The excellent adsorption performance, as well as the prominent irradiation stability allow the QTD‐COFs to be applied for the rapid removal of radioactive iodine. [ABSTRACT FROM AUTHOR]

The stability of covalent organic frameworks (COFs) is crucial for their applications in demanding environments. However, increasing the stability of COFs often comes with challenges such as higher synthesis difficulty, lower crystal quality, and reduced controllability during synthesis, making it difficult to regulate dimensions and morphology, thereby impacting the processing and shaping of stable COFs. Herein, the study presents a novel confined polymerization approach guided by hydrogen bonding preassembly to synthesize a soluble and stable COF featuring β-ketoenamine linkage. The presence of relatively weaker hydrogen bonds accelerates the orderly arrangement of monomers, ensuring appropriate spacing, and orientations among functional groups. This facilitates efficient covalent polymerization, leading to the creation of the framework while minimizing the "self-correction" mechanism during crystal growth, thereby enhancing the efficiency of COF synthesis. Furthermore, this method offers precise control over the size of the synthesized COF. The resulting crystalline COF can be toggled between dissolution and precipitation states, facilitating the fabrication of mixed matrix membranes (MMMs) through leveraging the solubility properties of COF. Overall, this pioneering strategy yields valuable insights for advancing weak bond assembly-mediated confined polymerization approaches, the controlled synthesis of stable COFs, and the preparation and processing of soluble COFs in diverse applications., (© 2024 Wiley‐VCH GmbH.)

Background: Hypertension is increasingly prevalent among young and middle-aged populations in rural China, accompanied by suboptimal self-management. Given that this population forms the backbone of the labor force, enhancing their self-management capabilities is crucial for improving overall population health. Studies indicate that individuals with good health literacy are more likely to effectively manage their health., Methods: Grounded in the health literacy skills framework, a model was constructed in this study to examine the impact of health literacy on self-management among young and middle-aged hypertensive patients in rural China. Meanwhile, the mediating roles of illness perception and self-efficacy were also verified. Using a multi-stage stratified random sampling method, 338 patients were recruited to participate in the study. Structural equation modeling was utilized to establish the relationship model, and bootstrap tests were carried out to examine the mediating effects., Results: The average self-management score was 70.45 ± 11.36. Health literacy exhibited a positive correlation with self-management (standardized β  = 0.372, p  < 0.001). The mediating effects through illness perception and self-efficacy were 0.040 and 0.236, constituting 6.68 and 39.31% of the total effect, respectively., Conclusion: Illness perception and self-efficacy serve as parallel mediators amid the association between health literacy and self-management. Implementing psychological counseling and health education is imperative for augmenting self-management competence and cultivating an adaptive coping mentality., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Liu, Jiang, Zhang, Niu, Cao, Du, Chen, Wang, Gong, Rao and Wu.)

Compared to the current mainstream rigid covalent organic frameworks (COFs) linked by imine bonds, flexible COFs have certain advantages of elasticity and self-adaptability, but their construction and application are greatly limited by the complexity in synthesis and difficulty in obtaining regular structure. Herein, we reported for the first time a series of flexible amine-linked COFs with high crystallinity synthesized by formic acid with unique catalytic and reductive bifunctional properties, rather than acetic acid, the most common catalyst for COF synthesis. The reaction mechanism was demonstrated to be a synchronous in situ reduction during the formation of imine bond. The flexibilities of the products endow them with accommodative adaptability to guest molecules, thus increasing the adsorption capacities for nitrogen and iodine by 27 % and 22 %, respectively. Impressively, a novel concept of flexibilization degree was proposed firstly, which provides an effective approach to rationally measure the flexibility of COFs., (© 2021 Wiley-VCH GmbH.)

We report the first example of 2D covalent organic framework nanosheets (Redox-COF1) for the selective reduction and in situ loading of valence-variable, redox-sensitive and long-lived radionuclides (abbreviated as VRL nuclides). Compared with sorbents based on chemical adsorption and physical adsorption, the redox adsorption mechanism of Redox-COF1 can effectively reduce the impact of functional group protonation under the usual high-acidity conditions in chemisorption, and raise the adsorption efficiency from the monotonous capture by pores in physisorption. The adsorption selectivity for UO 2 2+ reaches up to unprecedented ca. 97 % at pH 3, more than for any analogous adsorbing material., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To explore the effect of ouabain on intracellular Ca(2+) concentration ([Ca(2+)]i) in thoracic aorta vascular smooth muscle cells (VSMCs) in vitro., Methods: Primary SD rat thoracic aorta VSMCs were cultured by tissue adherent method and identified by immunochemistry. The binding ability between ouabain and VSMCs was detected by autoradiography, and fluo 3-AM (a Ca(2+) fluorescent probe) was employed to investigate whether ouabain affected VSMCs within a short period of time. The effect of a truncated fragment of the sodium pump α2 subunit was assayed in antagonizing the effect of ouabain on [Ca(2+)]i in the VSMCs., Results: Within the concentration range of 0.1-100 nmol/L, ouabain was found to dose-dependently bind to the VSMCs. Different concentrations of ouabain (0-3200 nmol/L) caused a transient, dose-dependent increase in [Ca(2+)]i in the VSMCs, which was antagonized by the application of the truncated fragment of sodium pump α2 subunit., Conclusions: Elevations in [Ca(2+)]i in the VSMCs can be the cytological basis of high ouabain-induced hypertension. The truncated fragment of the sodium pump α2 subunit can antagonize ouabain-induced increase of [Ca(2+)]i in the VSMCs, which provides a clue for understanding the pathogenesis of and devising a therapeutic strategy for high ouabain-induced hypertension.

Objective: To prepare polyclonal antibodies against sodium pump alpha 2 subunit M1-M2 extramembrane fragment (NKAα2 EM1) for studying the pathogenesis of hypertension., Methods: According to the GenBank data, the amino acid sequence of NKAα2 EM1 was obtained and the target peptide (LAAMEDEPSNDN) was synthesized using a peptide synthesizer with Fmoc method and purified with high-performance liquid chromatography. The synthesized peptide was then coupled to KLH for immunizing New Zealand white rabbits for 4 times to obtain the antiserum. The IgG antibodies against the synthetic peptide, after affinity purification with Protein A, were used for detecting NKAα2 EM1 expression in rat aortic vascular smooth muscle cells by enzyme-linked immunosorbent assay and immunocytochemistry (ICC)., Results: The synthesized peptide fragment , which consisted of 13 amino acid residues including one derivatized cysteine residue in the N-terminal (LAAMEDEPSNDN-C), had a theoretical relative molecular mass of 1408.48 D with a measured relative molecular mass of 1407.90 D and a purity exceeding 85.5%. The titer of the antiserum was more than 1:512 000, and the purified IgG antibody concentration was 0.965 mg/ml after purification with Protein A. At a 1:1000 dilution (final concentration of 1 µg/ml), the titer of the purified IgG antibody was more than 1:256 000. The purified IgG antibody could be used at 1:100 to 1:200 dilutions for for immunocytological examination of formalin-fixed cells., Conclusion: The anti-NKAα2 EM1 polyclonal antibodies obtained can be used in ELISA and immunocytochemistry for detecting the sodium pump alpha 2 subunit in formalin-fixed tissue or cells to facilitate investigation of the relationship between sodium pump and hypertension.