Bimetallic atom synergistic covalent organic framework for efficient electrochemical nitrate reduction.

Electrochemical reduction has emerged as an effective method to remove nitrate from industrial wastewater. Nevertheless, this method has been largely restricted by the lack of low-cost and efficient electrocatalysts. Here, we demonstrate a porous two-dimensional covalent organic framework (2D COF) material as a promising electrocatalyst, which is obtained via a Schiff base reaction by combining copper phthalocyanine with bipyridine sites for precise copper coordination. The bidentate coordinated COF material has a robust framework and stable chemical property, allowing the isolated Cu sites to be embedded into the regular pores with controlled and uniformly dispersed active centers. The well-defined design of the reaction monomers makes the COF material to trap nitrate ions more easily from aqueous solution. By rationally combining the synergistic effect of 2D COF and Cu active sites, the CuTAPc-CuBPy-COF electrocatalyst shows much higher nitrate reduction efficiency than CuTAPc-BPy-COF under low superpotential and different nitrate concentrations. The high NO3- conversion (90.3 %) and NH3 selectivity (69.6 %) are achieved. To our best acknowledge, this is the first demonstration of bi-copper-based COF material for NO3-RR electrocatalysis, which provides a new direction for the rational design of COFs as significant electrocatalysts for nitrate reduction.

A near infrared fluorescence probe with dual-site for hydrogen sulfide and sulfur dioxide detection.

Both hydrogen sulfide (H2S) and sulfur dioxide (SO2) are regarded as double-edged swords. They are toxic gases at high concentration, and at low concentration they are beneficial to the human. Therefore, it is of great significance to develop single chemosensor which enable to detect them with different fluorescence signal changes. In this work, a novel dual-site fluorescence probe (AMN-SSPy) with near infrared emission (675 nm) was designed, which realized quantitative detection for H2S and SO2 by fluorescence enhancement and fluorescence quenching, respectively. AMN-SSPy showed advantages such as excellent selectivity to H2S and SO2, strong anti-interference ability, high sensitivity for H2S (LOD 1.03 µM for H2S and 77.08 µM for SO2) and low toxicity. In addition, AMN-SSPy possessed the capacity to successfully image the endogenous and exogenous H2S, and it was also used to demonstrate that Ca2+ could induce accumulation of H2S in cell and zebrafish. Finally, the rapid detection of SO2 by AMN-SSPy in real samples was also established.

Assembly of soy protein-corn starch composite gels by thermal induction: Structure, and properties.

The effect of different corn starch (CS) concentrations on the gel formation of soybean isolate protein (SPI) was investigated. Moreover, the texture, rheological properties of the gel were determined, and the spatial structure and interactions of the composite gel system were analyzed. The composite system transitioned from liquid to solid-like with an increase in the CS concentration and did not backflow when inverted for 24 h. With the addition of CS, the gel strength, water holding capacity (WHC), G', and G'' increased significantly. The maximum was reached at 10 % starch concentration with gel strength of (228.96 ± 29.86) g and WHC of (98.93 ± 2.02)  %. According to low-field 1H nuclear magnetic resonance (LF-NMR) results, CS has a high water absorption capacity, which improved the WHC. The scanning electron microscopy results revealed that composite gels with a high CS concentration had a more dense and small void network structure. According to the results of molecular force interaction, infrared spectroscopy, Raman spectroscopy, and free sulfhydryl group analysis, the added starch promoted the unfolding of SPI molecules, exposure of hydrophobic groups, transformation of free sulfhydryl groups into disulfide bonds, and hydrogen bond formation. Hydrophobic interactions, disulfide bonding, and hydrogen bonding function together to form the SPI-CS composite gel system. The study results provide the basis for applying soy protein and CS gels.

Associations between urinary biomarkers of exposure to disinfection byproducts and semen parameters: A repeated measures analysis.

Toxicological studies have demonstrated that disinfection byproducts (DBPs), particularly haloacetic acids, cause testicular toxicity. However, evidence from human studies is sparse and inconclusive. This study included 1230 reproductive-aged men from the Tongji Reproductive and Environmental (TREE) cohort to investigate the associations between repeated measures of DBP exposures and semen parameters. Urinary dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) as biomarkers of DBP exposures and semen parameters in up to three samples from each man were assessed. The linear mixed effect models were applied to explore the associations between urinary biomarkers of DBP exposures and semen parameters. We found inverse associations of urinary DCAA with sperm count, progressive motility, and total motility (e.g., -14.86%; 95% CI: -19.33%, -10.15% in sperm total motility for the highest vs. lowest quartiles; all P for trends < 0.05). Moreover, urinary TCAA modeled as a continuous variable was negatively associated with sperm progressive motility and total motility, while the inverse associations across increasing urinary TCAA quartiles were seen among leaner men (BMI < 25 kg/m2). Exposure to DBPs reflected by urinary DCAA and TCAA was inversely associated with sperm motility and such effects were more evident among leaner men.

Icariin improves learning and memory function in Aß1-42-induced AD mice through regulation of the BDNF-TrκB signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Epimedium brevicornu Maxim. is a traditional medicinal Chinese herb that is enriched with flavonoids, which have remarkably high medicinal value. Icariin (ICA) is a marker compound isolated from the total flavonoids of Epimedium brevicornu Maxim. It has been shown to improve Neurodegenerative disease, therefore, ICA is probably a potential drug for treating AD. MATERIALS AND METHODS: The 6-8-week-old SPF-class male ICR mice were randomly divided into 8 groups for modeling, and then the mice were administered orally with ICA for 21 days. The behavioral experiments were conducted to evaluate if learning and memory behavior were absent in mice, confirming that infusion of Amyloid ß-protein (Aß)1-42 caused significant memory impairment. The morphological changes and damage of neurons in the mice's brains were observed by HE and Nissl staining. The spinous protrusions (dendritic spines) on neuronal dendrites were investigated by Golgi-Cox staining. The molecular mechanism of ICA was examined by Western Blot. The protein docking of ICA and Donepezil with BDNF were analyzed to determine their interaction. RESULTS: The behavioral experimental results showed that in Aß1-42-induced AD mice, the learning and memory abilities were improved after using ICA. At the same time, the low, medium, and high doses of ICA could reduce the content of Aß1-42 in the hippocampus of AD mice, repair neuronal damage, enhance synaptic plasticity, as well as increase the expression of BDNF, TrκB, CREB, Akt, GAP43, PSD95, and SYN proteins in the hippocampus of mice. However, the effect with high doses of ICA is more pronounced. The high-dose administration of ICA has the best therapeutic effect on AD mice. After administering the inhibitor k252a, the therapeutic effect of ICA was reversed. The macromolecular docking results of ICA and BDNF protein demonstrated a strong interaction of -7.8 kcal/mol, which indicates that ICA plays a therapeutic role in AD mice by regulating the BDNF-TrκB signaling pathway. CONCLUSIONS: The results confirm that ICA can repair neuronal damage, enhance synaptic plasticity, as well as ultimately improve learning and memory impairment through the regulation of the BDNF-TrκB signaling pathway.

The biological activity, functionality, and emulsion stability of soybean meal hydrolysate-proanthocyanidin conjugates.

The use of by-product hydrolysates as functional ingredients in food production is becoming more widespread. We hypothesized that the covalent binding of proanthocyanidin (PC) to soybean meal hydrolysates (SMHs) will improve the biological activity and function of the SMHs. Accordingly, we investigated the structure, antioxidant activity, and emulsion stability of SMHs after covalent conjugation with different concentrations of PC. An increase in PC addition resulted in the development of more high-molecular-weight SMHs-PC conjugates (40 kDa). The observed increase in the random coil content indicated that greater unfolding and disordered structure formation occurred with increasing PC addition. In addition, the fluorescence intensity and surface hydrophobicity of the SMHs increased, suggesting the presence of free amino acids, which likely contributed to the antioxidant activity and emulsifying properties of the SMHs. Addition of 3.0 mg/mL PC gave the SMHs-PC conjugates the highest antioxidant activity (ABTS+ and DPPH radical scavenging capacities of 89.08 ± 0.47 and 40.90 ± 1.53%, respectively) and emulsifying activity index (79.13 ± 2.80 m2/g), which may be attributed to protein unfolding and maximization of the polyphenol content when PC was covalently bound to the SMHs. Moreover, the SMHs-PC emulsion with 2.0 mg/mL PC showed the smallest particle size and highest viscosity, presenting promising potential as an emulsifier with high biological activity in food.

Changes in the structure and functional properties of soybean isolate protein: Effects of different modification methods.

Soybean protein isolate (SPI) is an important plant protein in food processing; however, its spherical structure prevents the exposure of its hydrophobic residues and affects its functional properties. In this study, we elucidate the effects of deamidation, phosphorylation, and glycosylation on the structure (Fourier-transform infrared spectroscopy, circular dichroism, fluorescence, and scanning electron microscopy) and functional properties (solubility, emulsifying activity index (EAI), and emulsifying stability index (ESI)) of SPI. The zeta potentials of the deamidated, phosphorylated, and glycosylated (DSPI, PSPI, and MSPI, respectively) samples decreased significantly (p < 0.05) relative to those of SPI. The functional properties of the modified SPI samples were improved, with MSPI-2 showing the best solubility (86.73 ± 0.34%), EAI (118.89 ± 0.73 m2/g), and ESI (273.33 ± 0.59 min). Moreover, the effects of the three modifications on the SPI functional properties increase in the order MSPI > PSPI > DSPI. These results provide a theoretical understanding the relationship between the modifications and SPI structure.

DNA induced CTAB-caped gold bipyramidal nanoparticles self-assembly using for Raman detection of DNA molecules.

DNA is an indispensable part of metabolism, which affects many important processes in the body, including gene expression, protein synthesis, and drug delivery. Surface-enhanced Raman spectroscopy (SERS) is one of the most important methods used to study the structure and function of DNA and can obtain rich DNA molecular fingerprints. However, it is still a great challenge to use SERS to directly analyze the characteristic Raman signals of the DNA molecule and achieve rapid and simple detection. Hence, a detection platform based on gold bipyramidal nanoparticles (AuNBs) self-assembly that can be directly used for the detection of DNA molecules without the need for additional aggregators and cleaning agents was designed in this study. The original hexadecyltrimethylammonium bromide (CTAB) of AuNBs can be used as the internal standard for DNA quantification without an additional standard. This is the first time that the Raman signals of the analyte molecule can be obtained directly without labels by using the interaction between the molecule and the enhanced substrate. We used this method to capture the original DNA molecules in methylated DNA, serum, and cell metabolites and obtained spectral data processing results using linear discriminant analysis (LDA). This provides new ideas for the digitization of disease treatment and the study of the metabolic processes of life.

Comprehensive genetic analysis reveals the mutational landscape of ABCA4-associated retinal dystrophy in a Chinese cohort.

PURPOSE: To depict the variant profiles of the ABCA4 gene in a large Chinese cohort of patients with ABCA4-associated retinal dystrophy (ABCA4-RD). METHODS: We recruited 290 unrelated Chinese patients with ABCA4-RD and did ABCA4 mutational screening by a combination of Sanger sequencing, targeted exome sequencing, entire ABCA4 locus sequencing, and whole genome sequencing (WGS). The pathogenicity of variants was assessed using in silico tools or in vitro splicing assays following the American College of Medical Genetics and Genomics guidelines. RESULTS: Two hundred sixty-eight distinct pathogenic variants were identified, and 57 were novel. In 580 alleles, 22 noncoding region variants outside canonical splice sites and 4 structural variations were found in 44 alleles accounting for 7.6% of all alleles. Bioinformatics analysis showed the complex mechanism of aberrant splicing productsnatural splice site disruption, branch point destruction, and cryptic splice site activation. Correspondingly, minigene assays validated the various abnormal splicing products, including exon skipping, exon elongation, partial exon deletion, and pseudoexon insertion. WGS identified the first inversion variation in ABCA4. CONCLUSIONS: This study systematically depicted the variant profiles of ABCA4 and revealed the missing alleles of patients with ABCA4-RD in a large Chinese cohort. Our findings demonstrated the complexity of molecular diagnosis of Mendelian diseases and the efficiency of WGS for detecting structural variants.

Oxidized dextran improves the stability and effectively controls the release of curcumin loaded in soybean protein nanocomplexes.

Dextran dialdehyde (ODex) was added to a nanocomplex of soy protein isolate (SPI)-curcumin (Cur) to improve its stability and achieve controlled release of Cur. The SPI-to-ODex mass ratio was optimized to achieve excellent properties and stability. Interactions between various components were confirmed by spectroscopic analysis, and the effect of ODex on the stability and bioactivity of SPI-Cur colloids was discussed. ODex was found to be crosslinked with SPI via the Schiff base reaction, which increased the ζ-potential and improved the surface hydrophobicity of nanocomplexes. At a SPI-to-ODex mass ratio of 20:1, the nanocomplex had a smaller particle size (199.2 nm), higher ζ-potential (-45.48 mV), and higher encapsulation efficiency (96.25%). Furthermore, adding ODex changed the network structure and effectively improved the thermal and storage stability of Cur as well as its antioxidant properties. Moreover, controlled release of Cur was observed during simulated digestion in the gastrointestinal environment.

Gallic acid-functionalized soy protein-based multiple cross-linked hydrogel: Mechanism analysis, physicochemical properties, and digestive characteristics.

Herein, carbodiimide hydrochloride/N-hydroxysuccinimide was used to mediate the grafting of gallic acid (GA) (0.005, 0.0015, and 0.025 wt%) with soybean protein isolate (SPI) in the preparation of SPI-GA conjugates and hydrogels. The modified materials were primarily joined via the CN bonds and exhibited excellent antioxidant properties. In addition, spectral analysis revealed that the grafting of GA increased the flexibility of the SPI structure. The SPI-GA hydrogel is fabricated through covalent/non-covalent cross-linking mechanisms, including Schiff base, Michael addition, and hydrogen bonding. Furthermore, the microstructure, rheological properties, thermal stability, and textural properties of the hydrogel were affected by the amount of GA grafted. The SPI-GA hydrogel exhibited the best performance when the amount of GA graft was 0.015 wt%. Furthermore, the tightly cross-linked structure of SPI-GA prevented premature degradation of the protein by pepsin. In conclusion, these capabilities provide numerous possibilities for the development of multifunctional and active substance delivery carriers.

Bibliometric analysis and systematic review of the adherence, uptake, translocation, and reduction of micro/nanoplastics in terrestrial plants.

Micro/nanoplastics are emerging agricultural pollutants globally. Micro/nanoplastics can adhere to terrestrial plant surfaces, be absorbed and transported by plants, and accumulate in the edible parts of plants, leading to the possibility of enrichment and transmission through the food chain and threatening human health. However, the underlying mechanism remains unclear. With increased studies on the internalization of micro/nanoplastics in terrestrial plants, a comprehensive and systematic review summarizing the current research trends and progress is warranted to provide a reference for further relevant research. Based on bibliometric analysis, this study focused on the mechanisms, study methods, and reduction techniques of micro/nanoplastics adherence, uptake, and translocation by terrestrial plants. The results showed that micro/nanoplastics can adhere to the surfaces of plant tissues such as seeds, roots, and leaves. Root uptake (root-to-leaf translocation) and foliar uptake (leaf-to-root translocation) are the two simultaneous internalization pathways of MNPs in plants. The observation methods included scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS), and inductively coupled plasma-mass spectrometry (ICP-MS). We highlighted the necessity and urgency of reducing the uptake and translocation of MNPs by plants and found that the application of silicon may be a promising approach for reducing internalization. This study identifies current knowledge gaps and proposes possible future needs.

Maprotiline Prompts an Antitumour Effect by Inhibiting PD-L1 Expression in Mice with Melanoma.

BACKGROUND: Research has revealed that the expression of PD-L1 is significantly upregulated in tumour cells and that the binding of programmed cell death protein 1 (PD-1) to programmed cell death 1 ligand 1 (PD-L1) inhibits the response of T cells, thereby suppressing tumour immunity. Therefore, blocking PD-L1/PD-1 signalling has become an important target in clinical immunotherapy. Some old drugs, namely, non-anticancer drugs, have also been found to have antitumour effects, and maprotiline is one of them. Maprotiline is a tetracyclic antidepressant that has been widely used to treat depression. However, it has not yet been reported whether maprotiline can exert an antitumour effect on melanoma. OBJECTIVE: This study aimed to investigate the antitumour efficacy of maprotiline in mice with melanoma. METHODS: In this study, female C57BL/6 mice were used to establish a tumour-bearing animal model. After treatment with maprotiline, the survival rate of mice was recorded daily. The expression of relevant proteins was detected by Western blotting, the proportion of immune cells was detected by flow cytometry, and the infiltration of immune cells in tumour tissue was detected by immunofluorescence staining. RESULTS: Maprotiline was found to inhibit the proliferation and migration of B16 cells while increasing cell apoptosis. Importantly, treatment with maprotiline decreased the expression of PD-L1 and increased the proportion of CD4+ T cells, CD8+ T cells, and NK cells in the spleen. It also increased the infiltration of CD4+ and CD8+ T cells in tumour tissue. CONCLUSION: Our research findings suggest that maprotiline enhances the antitumour immune response in mouse melanoma by inhibiting PD-L1 expression. This study may discover a new PD-L1 inhibitor, providing a novel therapeutic option for the clinical treatment of tumours.

Rapid marine degradable poly(butylene oxalate) by introducing promotion building blocks.

The design and development of high-performance marine-degradable plastics have long been considered a superior strategy to address marine plastic pollution. To achieve a balance between rapid marine degradability and high performance of polyester plastics, this work designed two series of poly(butylene oxalate) (PBOx) copolymers with intrinsic hydrolysis ability using poly(ethylene oxalate) (PEOx) and poly(glycolic acid) (PGA) as promotion building blocks. The synthesis process, crystallization properties, barrier performance, and mechanical properties of copolymers were comparatively investigated. Additionally, the marine degradability of copolymers received specific focus. The theoretical calculation demonstrated that the introduction of promotion blocks reduced the hydrolysis energy barrier of the copolymers. In general, the results revealed the advantages of PBEOx copolymer in satisfying practicality and better regulating marine degradability. The high gas barrier performance, suitable thermal properties, tunable mechanical properties, and rapid marine degradability endow the copolymer as a promising candidate toward sustainable and marine-degradable plastics.

Multiple regulatory roles of the transfer RNA-derived small RNAs in cancers.

With the development of sequencing technology, transfer RNA (tRNA)-derived small RNAs (tsRNAs) have received extensive attention as a new type of small noncoding RNAs. Based on the differences in the cleavage sites of nucleases on tRNAs, tsRNAs can be divided into two categories, tRNA halves (tiRNAs) and tRNA-derived fragments (tRFs), each with specific subcellular localizations. Additionally, the biogenesis of tsRNAs is tissue-specific and can be regulated by tRNA modifications. In this review, we first elaborated on the classification and biogenesis of tsRNAs. After summarizing the latest mechanisms of tsRNAs, including transcriptional gene silencing, post-transcriptional gene silencing, nascent RNA silencing, translation regulation, rRNA regulation, and reverse transcription regulation, we explored the representative biological functions of tsRNAs in tumors. Furthermore, this review summarized the clinical value of tsRNAs in cancers, thus providing theoretical support for their potential as novel biomarkers and therapeutic targets.

A dicyanoisophorone-based long-wavelength fluorescent probe for detection of cysteine in vitro and in vivo.

In this research, an "off-on" long-wavelength fluorescent probe (DCMN-Cl) based on (E)-2-(3-(2-(6-hydroxynaphthalen-2-yl)vinyl)-5,5-dimethylcyclohex-2-en-1-ylidene) malononitrile (DCMN) is designed and synthesized for cysteine (Cys) detection. DCMN-Cl exhibits a large Stokes shift (211 nm) and shows rapid response and high specificity to Cys. The fluorescence initensity at 635 nm reveals a good linear relationship with Cys concentration in the 0 to 50 µM range, and the detection limit is as low as 159 nM. The probe is also used for fluorescence imaging of Cys in cells and mice. Moreover, the probe provided visual evidence of Cu2+ and curcumin-induced intracellular Cys fluctuations.

Structure, ligands, and roles of GPR126/ADGRG6 in the development and diseases.

Adhesion G protein-coupled receptors (aGPCRs) are the second largest diverse group within the GPCR superfamily, which play critical roles in many physiological and pathological processes through cell-cell and cell-extracellular matrix interactions. The adhesion GPCR Adgrg6, also known as GPR126, is one of the better-characterized aGPCRs. GPR126 was previously found to have critical developmental roles in Schwann cell maturation and its mediated myelination in the peripheral nervous system in both zebrafish and mammals. Current studies have extended our understanding of GPR126-mediated roles during development and in human diseases. In this review, we highlighted these recent advances in GPR126 in expression profile, molecular structure, ligand-receptor interactions, and associated physiological and pathological functions in development and diseases.

Application of advanced oxidation processes for the removal of micro/nanoplastics from water: A review.

Micro/nanoplastics (MNPs) have been increasingly found in environments, food, and organisms, arousing wide public concerns. MNPs may enter food chains through water, posing a threat to human health. Therefore, efficient and environmentally friendly technologies are needed to remove MNPs from contaminated aqueous environments. Advanced oxidation processes (AOPs) produce a vast amount of active species, such as hydroxyl radicals (·OH), known for their strong oxidation capacity. As a result, an increasing number of researchers have focused on using AOPs to decompose and remove MNPs from water. This review summarizes the progress in researches on the removal of MNPs from water by AOPs, including ultraviolet photolysis, ozone oxidation, photocatalysis, Fenton oxidation, electrocatalysis, persulfate oxidation, and plasma oxidation, etc. The removal efficiencies of these AOPs for MNPs in water and the influencing factors are comprehensively analyzed, meanwhile, the oxidation mechanisms and reaction pathways are also discussed in detail. Most AOPs can achieve the degradation of MNPs, mainly manifest as the decrease of particle size and the increase of mass loss, but the mineralization rate is low, thus requiring further optimization for improved performance. Investigating various AOPs is crucial for achieving the complete decomposition of MNPs in water. AOPs will undoubtedly play a vital role in the future for the removal of MNPs from water.