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In this paper, two triazine ring–containing quaternary ammonium salt Gemini surfactants (C12-2-C12 and C14-2-C14) were synthesized. The minimum inhibitory concentrations against sulfate-reducing bacteria (SRB) of C12-2-C12, C14-2-C14 and dodecyl dimethyl benzyl ammonium chloride (1227) were determined using the double-dilution method. The performance of C12-2-C12 and C14-2-C14 in inhibiting carbon steel corrosion in the presence of SRB was examined, with 1227 serving as a control sample. The corrosion inhibition properties were assessed through static weight loss, electrochemical testing, and surface analysis. The interface adsorption behaviour of the corrosion inhibitor was explored via molecular dynamics simulations. Results indicate that the minimum inhibitory concentrations (MIC) of C12-2-C12 (0.021 mM) and C14-2-C14 (0.005 mM) are lower than that of 1227 (0.300 mM). The results of static weightlessness measurement reveal that the corrosion inhibition effects of the three surfactants on carbon steel soaked in SRB solution follow the order of C14-2-C14 > C12-2-C12 > 1227, with inhibition rates of 93.23 %, 88.45 %, and 76.49 % at a concentration of 0.2 mM, respectively. The adsorption behavior of these surfactants (1227, C12-2-C12, and C14-2-C14) on carbon steel surface in the presence of SRB conforms the Langmuir isotherm adsorption model. The outcomes of electrochemical experiments align with the static weight loss data. Furthermore, surface analysis results suggest that the surfactants can adsorb onto the carbon steel surface to form a protective film, thereby inhibiting SRB-induced corrosion.

Abstract Despite recent advances in extrusion bioprinting of cell‐laden hydrogels, using naturally derived bioinks to biofabricate complex elastic tissues with both satisfying biological functionalities and superior mechanical properties is hitherto an unmet challenge. Here, we address this challenge with precisely designed biological tough hydrogel bioinks featuring a double‐network structure. The tough hydrogels consisted of energy‐dissipative dynamically crosslinked glycosaminoglycan hyaluronic acid (o‐nitrobenzyl‐grafted hyaluronic acid) and elastin through Schiff's base reaction, and free‐radically polymerized gelatin methacryloyl. The incorporation of elastin further improved the elasticity, stretchability (∼170% strain), and toughness (∼45 kJ m−3) of the hydrogels due to the random coiling structure. We used this novel class of hydrogel bioinks to bioprint several complex elastic tissues with good shape retention. Furthermore, in vitro and in vivo experiments also demonstrated that the existence of elastin in the biocompatible bioinks facilitated improved cell behaviors and biological functions of bioprinted tissues, such as cell spreading and phenotype maintenance as well as tissue regeneration. The results confirmed the potential of the elastin‐containing tough hydrogel bioinks for bioprinting of 3D complex elastic tissues with biological functionalities, which may find widespread applications in elastic tissue regeneration.

Predicting potential drug-drug interactions (DDIs) can effectively mitigate unforeseen interactions throughout the entire drug development process, playing a pivotal role in ensuring drug safety. However, traditional methods are laborious and require specific expert knowledge. This paper proposes RPDAnet, a novel molecular substructure-aware network based on Reinforced Pooling and Deep Attention mechanism, to investigate the interactive relationships between drugs and predict the potential DDIs. Particularly, RPDAnet leverages reinforcement learning to dynamically select informative molecular fragments, thus enhancing its generalization capacity without relying on prior knowledge. Subsequently, RPDAnet develops Communicative Message Massing Neural Network (CMPNN) to enhance the representation of molecular structures by reinforcing message interactions between nodes and edges through a communicative kernel. Finally, RPDAnet aggregates the interactions between substructures of drugs to predict the DDI between a pair of drugs. The experimental results on two real-world datasets demonstrate that our proposed RPDAnet outperforms the state-of-the-art methods with more than 5% performance gains in DDI prediction.

Deep learning denoising methods are often constrained by the high cost of acquiring real-world noisy images and the labor-intensive process of dataset construction. Our self-supervised Multi-Scale Blind-Spot Network with Adaptive Feature Fusion (MA-BSN) addresses these issues, offering an efficient solution for image denoising. MA-BSN mitigates the challenges of spatial noise correlation preservation and limited receptive fields, which are prevalent in existing self-supervised denoising approaches. The network employs a blind-spot architecture that generates sub-images at multiple scales, enhancing denoising beyond the capabilities of pixel-shuffle downsampling. A depth-wise convolutional Transformer network (DTN) extracts features across a global receptive field, addressing the convolutional neural networks’ (CNNs) limitations. An adaptive feature fusion module (AFF) is introduced to refine feature learning for specific regions in the denoised images, leveraging attention mechanisms for improved performance. Our network’s efficacy is validated through experiments on the SIDD and DND real-world noise benchmark datasets. Results on the DND dataset show a PSNR/SSIM of 38.41 dB/0.940, surpassing state-of-the-art self-supervised methods and underscoring our approach’s superior denoising capability.

The issue of environmental pollution has received considerable critical attention in recent years. It is necessary to develop the green and efficient corrosion inhibitors. In this paper, the inhibition of doxazosin mesylate (DM) and terazosin hydrochloride (TH), as green corrosion inhibitors, were explored systematically by electrochemical impedance, polarization curves, SEM, AFM and contact angle. The effect of different heterocyclic amounts on the corrosion inhibition efficiency for Q235 steel in 1 M HCl was also discussed. It was found that DM showed the better performance than TH, with the best corrosion inhibition efficiency of 96.4 % at 1 mg/L. The FTIR and XPS analysis of the corroded Q235 steel surface revealed that the two drugs formed adsorption films on the steel surface and the types of adsorption were chemical and physical adsorption. Finally, the mechanism of the two drugs was analyzed in detail by isothermal adsorption simulations, quantum chemical calculations and molecular dynamics simulations.

Background: Procyanidins have antioxidative properties that may protect against age-related brain oxidative stress. Previous studies indicated that procyanidin-rich foods could improve cognitive function and prevent neurodegenerative diseases. This study hypothesized that grape seed procyanidins extract (GSPE) would have a favorable effect on cognitive function in elderly people with mild cognitive impairment (MCI). Methods: A community-based, randomized, double-blind, placebo-controlled trial was conducted. Participants aged 60 years or older with MCI were randomly assigned into the GSPE group (n = 35, 320 mg/d) or placebo group (n = 36), and received capsules for 6 months. Cognitive function was assessed using the Montreal Cognitive Assessment Scale (MoCA). The change in MoCA scores between groups were tested by the time ✕ treatment interaction in mixed-design ANOVA. Results: After 6 months of intervention, the MoCA score was higher than the baseline both in the intervention group and placebo control group, while the there was no significant difference for mean change in MoCA score from baseline between the intervention group and the placebo group (2.35 ± 3.20 vs. 1.28 ± 2.93, P = 0.192). Conclusions: Present study showed that 6-month supplementation with GSPE did not significantly improve cognitive function in subjects with MCI. Further investigations regarding the longer-term intervention effect of procyanidins extract on mild or moderate cognitive disorders are needed.

At present, the development of efficient green corrosion inhibitors has become one of the important directions of metal corrosion protection. In this paper, biomass carbon quantum dots (BCQDs) were prepared by hydrothermal reaction using biomass precursors. The optical properties and structural composition of the synthesized BCQDs were characterized in detail. After that, the corrosion inhibition performance of BCQDs was evaluated by EIS, Tafel, SEM and TEM. The electrochemistry and surface tests demonstrate that the aggregates can effectively prevent Q235 steel from corrosion in 1 M HCl medium at 298 K-328 K, with the maximum inhibition efficiency of 94.1 % at the concentration of 200 mg/L at 308 K. Finally, the corrosion inhibition mechanism was analyzed by FTIR, CA and XPS on the surface of the corroded carbon steel samples. The inhibition mechanism suggests that BCQDs can inhibit metal corrosion by self-aggregation and adsorption on metal surface. This is owing to its small size effect and functional groups containing heteroatoms, easily forming dense protective film.

At present, the types of pollutants in wastewater are more and more complicated, however, the multifunctional membrane materials are in short supply. To prepare a membrane with both high efficient oil-in-water emulsion separation performance and photocatalytic degradation performance of organic dyes, the bifunctional separation membrane was successfully prepared by electrostatic spinning technology of PVDF/PEMA and in situ deposition of anatase TiO2 nanoparticles containing Ti3+ and oxygen vacancies (Ov). The prepared composite membrane has excellent hydrophilic properties (WCA = 15.65), underwater oleophobic properties (UOCA = 156.69), and photocatalytic performance. These composite membranes have high separation efficiency and outstanding anti-fouling performance, the oil removal efficiency reaches 98.95%, and the flux recovery rate (FRR) reaches 99.19% for soybean oil-in-water emulsion. In addition, the composite membrane has outstanding photocatalytic degradation performance, with 97% and 90.2% degradation of RhB and AG-25 under UV conditions, respectively. Several oil-in-water separation and dye degradation experiments show that the PVDF composite membrane has excellent reuse performance. Based on these results, this study opens new avenues for the preparation of multifunctional reusable membranes for the water treatment field.

Aiming at revealing the structural diversity of secondary metabolites and the different patterns in wild-simulated American ginseng (WsAG) and field-grown American ginseng (FgAG), a comprehensive and unique phytochemical profile study was carried out. In the screening analysis, a total of 121 shared compounds were characterized in FgAG and WsAG, respectively. The results showed that both of these two kinds of American ginseng were rich in natural components, and were similar in terms of the kinds of compound they contained. Furthermore, in non-targeted metabolomic analysis, when taking the contents of the constituents into account, it was found that there indeed existed quite a difference between FgAG and WsAG, and 22 robust known biomarkers enabling the differentiation were discovered. For WsAG, there were 12 potential biomarkers including two ocotillol-type saponins, two steroids, six damarane-type saponins, one oleanane-type saponins and one other compound. On the other hand, for FgAG, there were 10 potential biomarkers including two organic acids, six damarane-type saponins, one oleanane-type saponin, and one ursane. In a word, this study illustrated the similarities and differences between FgAG and WsAG, and provides a basis for explaining the effect of different growth environments on secondary metabolites.

With the aim to discuss the similarities and differences of phytochemicals in Moringa oleifera leaves collected from China (CML) and India (IML) in mind, comparative ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC-QTOF-MS) analysis was performed in this study. A screening analysis based on a UNIFI platform was first carried out to discuss the similarities. Next, untargeted metabolomic analysis based on multivariate statistical analysis was performed to discover the differences. As a result, a total of 122 components, containing 118 shared constituents, were characterized from CML and IML. The structure types included flavonoids, alkaloids, glyosides, organic acids and organic acid esters, iridoids, lignans, and steroids, etc. For CML, 121 compounds were characterized; among these, 18 potential biomarkers with higher contents enabled differentiation from IML. For IML, 119 compounds were characterized; among these, 12 potential biomarkers with higher contents enabled differentiation from CML. It could be concluded that both CML and IML are rich in phytochemicals and that CML is similar to IML in the kinds of the compounds it contains, except for the significant differences in the contents of some compounds. This comprehensive phytochemical profile study provides a basis for explaining the effect of different growth environments on secondary metabolites and exists as a reference for further research into or applications of CML in China.

Pharmacokinetic and metabolism studies were carried out on curculigoside C (CC), a natural product with good antioxidant and neuroprotective effects, with the purpose of investigating the effects of the hydroxyl group at C-3′ in curculigoside. A rapid and sensitive method with UPLC-MS was developed and fully validated for the first time in the pharmacokinetic analysis for quantification of CC in rat plasma. The assay was linear (R2 > 0.9984) over the concentration range of 1⁻2500 ng/mL, with the lower limit of quantification (LLOQ) being 1 ng/mL. The intra-day and inter-day precision (expressed as relative standard deviation, RSD) ranged from 4.10% to 5.51% and 5.24% to 6.81%, respectively. The accuracy (relative error, RE) ranged from −3.28% to 0.56% and −5.83% to −1.44%, respectively. The recoveries ranged from 92.14% to 95.22%. This method was then applied to a pharmacokinetic study of rats after intragastric administration of 15, 30 and 60 mg/kg CC. The results revealed that CC exhibited rapid oral absorption (Tmax = 0.106 h, 0.111 h, and 0.111 h, respectively), high elimination (t1/2 = 2.022 h, 2.061 h, and 2.048 h, respectively) and low absolute bioavailability (2.01, 2.13, and 2.39%, respectively). Furthermore, an investigation on the metabolism of CC was performed by UPLC-QTOF-MSE. Twelve metabolites of CC from plasma, bile, urine and faeces of rats were confirmed. The main metabolic pathways of CC, which involve dehydration, glucosylation, desaturation, formylation, cysteine conjugation, demethylation and sulfonation, were profiled. In conclusion, this research has developed a sensitive quantitative method and demonstrated the metabolism of CC in vivo.

Aiming at further systematically comparing the similarities and differences of the chemical components in ginseng of different ages, especially comparing the younger or the older and mountain-cultivated ginseng (MCG), 4, 5, 6-year-old cultivated ginseng (CG) and 12, 20-year-old MCG were chosen as the analytical samples in the present study. The combination of UPLC-QTOF-MSE, UNIFI platform and multivariate statistical analysis were developed to profile CGs and MCGs. By the screening analysis based on UNIFI, 126 chemical components with various structural types were characterized or tentatively identified from all the CG and MCG samples for the first time. The results showed that all the CG and MCG samples had the similar chemical composition, but there were significant differences in the contents of markers. By the metabolomic analysis based on multivariate statistical analysis, it was shown that CG4–6 years, MCG12 years and MCG20 years samples were obviously divided into three different groups, and a total of 17 potential age-dependent markers enabling differentiation among the three groups of samples were discovered. For differentiation from other two kinds of samples, there were four robust makers such as α-linolenic acid, 9-octadecenoic acid, linoleic acid and panaxydol for CG4–6 years, five robust makers including ginsenoside Re1, -Re2, -Rs1, malonylginsenoside Rb2 and isomer of malonylginsenoside Rb1 for MCG20 years, and two robust makers, 24-hydroxyoleanolic acid and palmitoleic acid, for MCG12 years were discovered, respectively. The proposed approach could be applied to directly distinguish MCG root ages, which is an important criterion for evaluating the quality of MCG. The results will provide the data for the further study on the chemical constituents of MCG.

Pharmacokinetic and metabolism studies of 12-riboside-pseudoginsengenin DQ (RPDQ), a novel ginsenoside with an anti-cancer effect, were carried out, aiming at discussing the characteristics of the ginsenoside with glycosylation site at C-12. In the pharmacokinetic analysis, we developed and validated a method by UPLC-MS to quantify RPDQ in rat plasma. In the range of 5–1000 ng/mL, the assay was linear (R2 > 0.9966), with the LLOQ (lower limit of quantification) being 5 ng/mL. The LOD (limit of detection) was 1.5 ng/mL. The deviations of intra-day and inter-day, expressed as relative standard deviation (RSD), were ≤ 3.51% and ≤ 5.41% respectively. The accuracy, expressed as relative error (RE), was in the range –8.82~3.47% and –5.61~2.87%, respectively. The recoveries were in the range 85.66~92.90%. The method was then applied to a pharmacokinetic study in rats intragastrically administrated with 6, 12, and 24 mg/kg RPDQ. The results showed that RPDQ exhibited slow oral absorption (Tmax = 7.0 h, 7.5 h, and 7.0 h, respectively), low elimination (t1/2 = 12.59 h, 12.83 h, and 13.74 h, respectively) and poor absolute bioavailability (5.55, 5.15, and 6.08%, respectively). Moreover, the investigation of metabolites were carried out by UPLC-QTOF-MS. Thirteen metabolites of RPDQ were characterized from plasma, bile, urine, and feces of rats. Some metabolic pathways, including oxidation, acetylation, hydration, reduction, hydroxylation, glycine conjugation, sulfation, phosphorylation, glucuronidation, glutathione conjugation, and deglycosylation, were profiled. In general, both the rapid quantitative method and a good understanding of the characteristics of RPDQ in vivo were provided in this study.

Blood stasis syndrome (BSS) is one of the most common Chinese medicine patterns in coronary heart disease. Our previous work proved that Xueshuan Xinmaining Tablet (XXT) could treat blood stasis through regulating the expression of F13a1, Car1 and Tbxa2r. In the current study, the effect and mechanism of XXT on BSS was comprehensively and holistically investigated based on a metabolomics approach. Urine and plasma samples of 10 BBS rats treated with XXT (XT), 9 BSS model rats (BM) and 11 normal control (NC) rats were collected and then determined by UPLC-Q/TOP-MS. Multivariate analyses were applied to distinguish differentiate urinary and plasma metabolite patterns between three groups. Results showed that a clear separation of three groups was achieved. XT group was located between BM group and NC group, and showing a tendency of recovering to NC group, which was consistent with the results of hemorheological studies. Some significantly changed metabolites like cortexolone, 3α,21-dihydroxy-5β-pregnane-11,20-dione and 19S-hete and leukotriene A4, chiefly involved in steroid hormone biosynthesis, arachidonic acid metabolism and lipid metabolism, were found and identified to explain the mechanism. These potential markers and their corresponding pathways will help explain the mechanism of BSS and XXT treatment. This work also proves that metabolomics is effective in traditional Chinese medicinal research.

Traditionally, human embryonic stem cells (hESCs) are cultured on inactivated live feeder cells. For clinical application using hESCs, there is a requirement to minimize the risk of contamination with animal components. Extracellular matrix (ECM) derived from feeder cells is the most natural way to provide xeno-free substrates for hESC growth. In this study, we optimized the step-by-step procedure for ECM processing to develop a xeno-free ECM that supports the growth of undifferentiated hESCs. In addition, this newly developed xeno-free substrate can be stored at 4°C and is ready to use upon request, which serves as an easier way to amplify hESCs for clinical applications.

Platycodonis radix is extensively used for treating cough, excessive phlegm, sore throat, bronchitis and asthma in the clinic. Meanwhile, the stems, leaves and seeds of Platycodon grandiflorum (PG) have some pharmaceutical activities such as anti-inflammation and anti-oxidation effects, etc. These effects must be caused by the different metabolites in various parts of herb. In order to profile the different parts of PG, the ultra-high performance liquid chromatography combined with quadrupole time-of- flight mass spectrometry (UPLC-QTOF-MSE) coupled with UNIFI platform and multivariate statistical analyses was used in this study. Consequently, for the constituent screening, 73, 42, 35, 44 compounds were characterized from the root, stem, leaf and seed, respectively. The stem, leaf and seed contain more flavonoids but few saponins that can be easily discriminated in the root. For the metabolomic analysis, 15, 5, 7, 11 robust biomarkers enabling the differentiation among root, stem, leaf and seed, were discovered. These biomarkers can be used for rapid identification of four different parts of PG grown in northeast China.

An efficient and convenient protocol for the synthesis of 2H-chromenones has been developed. In the presence of tBuOK in DMF, good to excellent yields of various chromenones were obtained from the corresponding salicylaldehydes and arylacetonitriles. No protection of inert gas atmosphere is required here.