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Neuroblastoma (NB), an embryonic tumor of the autonomous nervous system, poses a significant threat to the health and lives of children. Accurate measurement of vanillylmandelic acid (VMA) and homovanillic acid (HVA) in human urine is crucial for screening and diagnosis of NB. Although various laboratories have developed liquid chromatography tandem mass spectrometry (LC-MS/MS) method to detect VMA and HVA, the comparability between the results obtained from different laboratories and methods was poor. The absence of reference method for VMA and HVA hinders the standardization of their measurements. Therefore, a candidate reference measurement procedure (cRMP) based on isotope dilution LC-MS/MS (ID-LC-MS/MS) for the detection of VMA and HVA in human urine was established. Urine samples were spiked with VMA-d3 and HVA-d5 as internal standards and extracted using a protein precipitation method. The cRMP exhibited desirable precision with the total imprecision below 5 %. The accuracy of this cRMP was demonstrated by the high analytical recovery (98.64 % - 102.22 % and 98.41 % - 100.97 % for VMA and HVA, respectively), and comparability between different reference systems. The limit of detection for HVA and VMA were 15.625 ng/mL and 3.906 ng/mL, respectively; the quantification limits were 62.5 ng/mL and 7.813 ng/mL, respectively, which can meet the clinical detection requirements. The linear range was from 78.125 ng/mL to 20 μg/mL. Specificity evaluations showed no corresponding interference from structurally similar analogs. In conclusion, we have established a cRMP based on ID-LC-MS/MS for the measurement of VMA and HVA in urine samples, demonstrating well-defined method performance including accuracy, precision, and specificity. This newly established cRMP is suitable for routine assay standardization and evaluation of clinical samples. Furthermore, this method has the potential to significantly enhance the diagnostic accuracy for neuroblastoma., Competing Interests: Declaration of Competing Interest All authors declare that they have no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Silk nanofibrils (SNFs), the fundamental building blocks of silk fibers, endow them with exceptional properties. However, the intricate mechanism governing SNF assembly, a process involving both protein conformational transitions and protein molecule conjunctions, remains elusive. This lack of understanding has hindered the development of artificial silk spinning techniques. In this study, we address this challenge by employing a graphene plasmonic infrared sensor in conjunction with multi-scale molecular dynamics (MD). This unique approach allows us to probe the secondary structure of nanoscale assembly intermediates (0.8-6.2 nm) and their morphological evolution. It also provides insights into the dynamics of silk fibroin (SF) over extended molecular timeframes. Our novel findings reveal that amorphous SFs undergo a conformational transition towards β-sheet-rich oligomers on graphene. These oligomers then connect to evolve into SNFs. These insights provide a comprehensive picture of SNF assembly, paving the way for advancements in biomimetic silk spinning., (© 2024. The Author(s).)

Advanced glycation end products (AGEs), derived from the non-enzymatic glycation reaction, are defined as glycotoxins in various diseases including aging, diabetes and kidney injury. Exploring AGEs as potential biomarkers for these diseases holds paramount significance. Nevertheless, the high chemical structural similarity and great heterogeneity among AGEs present a formidable challenge when it comes to the comprehensive, simultaneous, and accurate detection of multiple AGEs in biological samples. In this study, an UPLC/MS/MS method for simultaneous quantification of 20 free AGEs in human serum was firstly established and applied to quantification of clinical samples from individuals with kidney injury. Simple sample preparation method through protein precipitation without derivatization was used. Method performances including imprecision, accuracy, sensitivity, linearity, and carryover were systematically validated. Intra- and inter- imprecision of 20 free AGEs were 1.93-5.94 % and 2.30-8.55 %, respectively. The method accuracy was confirmed with good recoveries ranging from 96.40 % to 103.25 %. The LOD and LOQ were 0.1-3.13 ng/mL and 0.5-6.25 ng/mL, respectively. Additionally, the 20 free AGEs displayed excellent linearity (R 2 >0.9974) across a wide linear range (1.56-400 ng/mL). Finally, through simultaneous quantitation of 20 Free AGEs in 100 participants including kidney injury patient and healthy controls, we identified six free AGEs, including N 6 -carboxyethyl-L-arginine (CEA), N 6 -carboxymethyl-L-lysine (CML), methylglyoxal-derived hydroimidazolones (MG-H), N 6 -formyl-lysine, N 6 -carboxymethyl-L-arginine (CMA), and glyoxal-derived hydroimidazolone (G-H), could well distinguish kidney injury patients and healthy individuals. Among them, the levels of four free AGEs including CML, CEA, MG-H, and G-H strongly correlate with traditionally clinical markers of kidney disease. The high area under the curve (AUC) values (AUC=0.965) in receiver operating characteristic (ROC) curve indicated that these four free AGEs can be served as combined diagnostic biomarkers for the diagnosis of kidney disease., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Solar water splitting has gained increasing attention in converting solar energy into green hydrogen energy. However, the construction of a photothermo-electro coupling field by harnessing light-induced heat and its enhancement on solar water splitting were seldom studied. Herein, we developed a full-spectrum responsive photoanode by depositing Cd x Zn 1- x S onto the surface of hydrogenated TiO 2 nanotube array (H-TNA), followed by modification with Ni 2 P. The resulting ternary photoanode exhibits a photocurrent density of 4.99 mA·cm -2 at 1.23 V vs. RHE with photoinduced heating, which is 11.9-fold higher than that of pristine TNA, with an optimal ABPE of 2.47%. The characterization results demonstrate that the ternary photoanode possesses superior full-spectrum absorption and efficient photogenerated carrier separation driven by the interface electric fields. Additionally, Ni 2 P reduces the hole injection barrier and increases surface active sites, accelerating the consumption of holes accumulating on the relatively unstable Cd x Zn 1- x S to simultaneously improve the activity and stability of water splitting. Moreover, temperature-dependent measurements reveal that H-TNA and Ni 2 P significantly motivate the photothermal conversion to construct a photothermo-electro coupling field, optimizing photoelectric conversion and charge carrier-induced surface reactions. This work contributes to understanding the synergistic effect of the photothermo-electro coupling field on the photoelectrochemical water splitting.

Extended surfactants represent a novel class of anionic-nonionic surfactants with exceptional performance and unique application value in chemically enhanced oil recovery. Although molecular dynamics (MD) simulations can efficiently screen these surfactants, the current research is limited. Here, it is proven for the first time that existing generic force fields (GAFF and CHARMM) cannot accurately describe extended surfactants, and traditional approaches are insufficient for obtaining precise charge parameters. The concept of the respectively optimized force field (ROFF) with the purports of specialization and accuracy is proposed to construct high-accuracy models for MD simulations, and a new approach is developed to simulate the interface model. By combining the newly specialized alkane model, ROFF-based surfactant models, and the innovative simulation protocol, high accuracy and reliability can be obtained in predicting hydration free energies, minimum of area per molecule, and critical micelle concentration of extended surfactants. Key properties of the newly designed extended surfactants in conventional oil-water interfaces and oil reservoir environments are comprehensively predicted by using advanced analytical and characterization methods. Furthermore, the more rigorous mechanism underlying the special amphiphilicity of the extended surfactant is revealed, potentially offering significant improvements over previous empirical perspectives.

In this paper, we propose a method that uses the idea of decoupling and unites edge information for semantic segmentation. We build a new dual-stream CNN architecture that fully considers the interaction between the body and the edge of the object, and our method significantly improves the segmentation performance of small objects and object boundaries. The dual-stream CNN architecture mainly consists of a body-stream module and an edge-stream module, which process the feature map of the segmented object into two parts with low coupling: body features and edge features. The body stream warps the image features by learning the flow-field offset, warps the body pixels toward object inner parts, completes the generation of the body features, and enhances the object's inner consistency. In the generation of edge features, the current state-of-the-art model processes information such as color, shape, and texture under a single network, which will ignore the recognition of important information. Our method separates the edge-processing branch in the network, i.e., the edge stream. The edge stream processes information in parallel with the body stream and effectively eliminates the noise of useless information by introducing a non-edge suppression layer to emphasize the importance of edge information. We validate our method on the large-scale public dataset Cityscapes, and our method greatly improves the segmentation performance of hard-to-segment objects and achieves state-of-the-art result. Notably, the method in this paper can achieve 82.6% mIoU on the Cityscapes with only fine-annotated data.

Millepachine, a bioactive natural product isolated from the seeds of Millettia pachycarpa, is reported to display potential antitumor activity. In this study, novel indole-containing hybrids derived from millepachine were designed, synthesized and evaluated for their antitumor activities. Among all the compounds, compound 14b exhibited the most potent cytotoxic activity against five kinds of human cancer cell lines, with IC 50 values ranging from 0.022 to 0.074 μM, making it almost 100 times more active than millepachine. Valuable structure-activity relationships (SARs) were obtained. Furthermore, the mechanism studies showed that compound 14b induced cell-cycle arrest at the G2/M phase by inhibiting tubulin polymerization and further induced cell apoptosis through reactive oxygen species (ROS) accumulation and mitochondrial membrane potential (MMP) collapse. In addition, the low cytotoxicity toward normal human cells and equivalent sensitivity towards drug-resistant cells of compound 14b highlighted its potential for the development of antitumor drugs.

The Li metal anode is considered one of the most potential anodes due to its highest theoretical specific capacity and the lowest redox potential. However, the scalable preparation of safe Li anodes remains a challenge. In the present study, a LiF-rich protection layer has been developed using self-driven chemical reactions between the Li 3 x La 2/3- x TiO 3 /polyvinylidene fluoride/dimethylacetamide (LLTO/PVDF/DMAc) solution and the Li metal. After coating the LLTO/PVDF/DMAc solution to Li foil, PVDF reacted with Li spontaneously to form LiF, and the accompanying Ti 4+ ions (in LLTO) were reduced to Ti 3+ to form a mixed ionic and electronic conductor Li x LLTO. The protective layer can redistribute the Li-ion transport, regulate the even Li deposition, and inhibit the Li dendrite growth. When paired with LiFePO 4 , NCM811, and S cathodes, the batteries have demonstrated excellent capacity retention and cycling stability. More importantly, a volumetric energy density of 478 Wh L -1 and 78% capacity retention after 310 cycles have been achieved by using a S/Li x LLTO-Li pouch cell. This work provides a feasible avenue to provide large-scale preparation of safe Li anodes for the next-generation pouch-type Li-S batteries as ideal power sources for flexible electronic devices.

The introduction of a dual-functional interlayer into lithium-sulfur batteries (LSBs) provides many opportunities for restraining the "shuttle effect" and enhancing sluggish sulfur conversion kinetics. Tuning the band structure of the metal sulfide provides an opportunity to enhance its catalytic activity, which plays an important role in suppressing the "shuttle effect" of lithium polysulfides (LiPSs) in LSBs. Here were present a Co 9 S 8 @MoS 2 core-shell heterostructure anchored to a carbon nanofiber (Co 9 S 8 @MoS 2 /CNF), developed as an interlayer for suppressing the shuttle effect of LiPSs. The fabricated composite heterostructure is determined to be an effective alternative material that combines the synergistic relationship between chemisorption and electrochemical catalysis. We find that the band structure of the MoS 2 shell can be effectively tuned by the Co 9 S 8 core and that the Co 9 S 8 @MoS 2 /CNF can capture the LiPSs, providing excellent catalytic ability to convert LiPSs into Li 2 S 2 , with subsequent transformation from Li 2 S 2 to Li 2 S. Importantly, high capacities of 1002 and 986 mAh g -1 can be retained after 50 cycles with high-sulfur loadings of 6 and 10 mg cm -2 . Our results highlight the design of an atomic-scale heterostructure as a multifunctional interlayer providing a synergistic relationship between adsorption and catalysis. The net result is an effective retardation of the shuttling of LiPSs and an enhancement of the electrochemical redox reactions of LiPSs. This work shows great promise toward the development of practical applications of LSBs.

Here we reported novel apigenin-rivastigmine hybrids were rationally designed and synthesized by the multi-target-directed ligands (MTDLs) strategy, their activity in vitro results revealed that compound 3d showed significant antioxidant potency (ORAC = 1.3 eq), and it was a reversible huAChE (IC 50  = 6.8 μM) and huBChE (IC 50  = 16.1 μM) inhibitor. 3d also served as a selective metal chelator, and it significantly inhibited and disaggregated self-mediated and Cu 2+ -mediated Aβ 1-42 aggregation, and also inhibited hAChE-mediated induced Aβ 1-40 aggregation. Compound 3d exhibited remarkable neuroprotective effect and hepatoprotective activity. In addition, compound 3d presented favourable blood-brain barrier penetration in vitro and drug-like property. Further, the in vivo assay displayed that 3d indicated remarkable dyskinesia recovery rate and response efficiency on AD zebrafish, and exhibited surprising protective effect on Aβ 1-40 -mediated zebrafish vascular injury. More importantly, 3d did not indicate obvious acute toxicity at dose up to 2000 mg/kg, and could improve scopolamine-induced memory impairment. Subsequently, the regulation of multi-targets for 3d were further confirmed through transcriptome sequencing of brain hippocampi, which also offered novel potential targets and opened a new way to treat Alzheimer's disease. More interestingly, the metabolism of 3din vitro indicated that 4 metabolites in rat liver microsome metabolism, 2 metabolites in human liver microsome metabolism, and 4 metabolites in intestinal flora metabolism, which offered supports for the preclinical study of 3d. Overall, this study exhibited that compound 3d was a promising advanced compound targeted multiple factors associated with AD., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Using polymer electrolytes with relatively high mechanical strength, enhanced safety, and excellent flexibility to replace the conventional liquid electrolytes is an effective strategy to curb the Li-dendrite growth in Li-metal batteries (LMBs). However, low ionic conductivity, unsatisfactory thermal stability, and narrow electrochemical window still hinder their applications. Here, we fabricate Li 0.35 La 0.55 TiO 3 (LLTO) nanofiber-enabled poly(vinylidene fluoride) (PVDF)-based composite polymer electrolytes (CPEs) with enhanced mechanical property and wide electrochemical window. The results show that 15 wt % of LLTO nanofibers synergize with PVDF, giving a flexible electrolyte membrane with significantly improved performance, such as high ionic conductivity (5.3 × 10 -4 S cm -1 ), wide electrochemical window (5.1 V), high mechanical strength (stress 9.5 MPa, strain 341%), and good thermal stability (thermal degradation 410 °C). In addition, an all-solid-state Li-metal battery of sandwich-type LiFePO 4 /PVDF-CPE (15 wt % of LLTO)/Li delivers satisfactory cycling stability and outstanding rate performance. A reversible capacity of 121 mA h g -1 is delivered at 1 C after 100 cycles. This work exemplifies that the introduction of LLTO nanofibers can improve the electrochemical performances of PVDF-based CPEs used as electrolytes for all-solid-state LMBs.

A series of novel phthalimide-alkylamine derivatives were synthesized and evaluated as multi-functions inhibitors for the treatment of Alzheimer's disease (AD). The results showed that compound TM-9 could be regarded as a balanced multi-targets active molecule. It exhibited potent and balanced inhibitory activities against ChE and MAO-B (huAChE, huBuChE, and huMAO-B with IC 50 values of 1.2μM, 3.8μM and 2.6 μM, respectively) with low selectivity. Both kinetic analysis of AChE inhibition and molecular modeling study suggested that TM-9 binds simultaneously to the catalytic active site and peripheral anionic site of AChE. Interestingly, compound TM-9 abided by Lipinski's rule of five. Furthermore, our investigation proved that TM-9 indicated weak cytotoxicity, and it could cross the blood-brain barrier (BBB) in vitro. The results suggest that compound TM-9, an interesting multi-targeted active molecule, offers an attractive starting point for further lead optimization in the drug-discovery process against Alzheimer's disease., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

A series of 2-acetyl-5-O-(amino-alkyl)phenol derivatives was designed, synthesized and evaluated as multi-function inhibitors for the treatment of Alzheimer's disease (AD). The results revealed that compound TM-3 indicated selective AChE inhibitory potency (eeAChE, IC 50  = 0.69 μM, selective index (SI) = 32.7). Both kinetic analysis of AChE inhibition and molecular modeling study suggested that TM-3 could simultaneously bind to the catalytic active site and peripheral anionic site of AChE. And TM-3 was also a highly selective MAO-B inhibitor (IC 50  = 6.8 μM). Moreover, TM-3 could act as antioxidant (ORAC value was 1.5eq) and neuroprotectant, as well as a selective metal chelating agent. More interestingly, compound TM-3 could cross the blood-brain barrier (BBB) in vitro and abided by Lipinski's rule of five. Therefore, compound TM-3, a promising multi-targeted active molecule, offers an attractive starting point for further lead optimization in the drug-discovery process against AD., (Copyright © 2017. Published by Elsevier Ltd.)

A new family of multitarget molecules able to interact with acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), as well as with monoamino oxidase (MAO) A and B, has been synthesized. Novel 3,4-dihydro-2(1H)-quinoline-O-alkylamine derivatives have been designed using a conjunctive approach that combines the JMC49 and donepezil. The most promising compound TM-33 showed potent and balance inhibitory activities toward ChE and MAO (eeAChE, eqBuChE, hMAO-A and hMAO-B with IC 50 values of 0.56μM, 2.3μM, 0.3μM and 1.4μM, respectively) but low selectivity. Both kinetic analysis of AChE inhibition and molecular modeling study suggested that TM-33 binds simultaneously to the catalytic active site and peripheral anionic site of AChE. Furthermore, our investigation proved that TM-33 could cross the blood-brain barrier (BBB) in vitro, and abided by Lipinski's rule of five. The results suggest that compound TM-33, an interesting multi-targeted active molecule, offers an attractive starting point for further lead optimization in the drug-discovery process against Alzheimer's disease., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

A series of novel ferulic acid-O-alkylamines derivatives were designed, synthesized, and evaluated as multitarget-directed ligands against Alzheimer's disease. In vitro studies displayed that all the synthesized target compounds showed impressive inhibitory activity against butyrylcholinesterase (BuChE), significant inhibition/disaggregation of self-induced β-amyloid (Aβ) aggregation and acted as potential antioxidants. Particularly, compound 7f, one of the most potent BuChE inhibitor (IC 50 value of 0.021 μM for equine serum BuChE, 8.63 μM for ratBuChE and 0.07 μM for human serum BuChE), was found to be a good acetylcholinesterase (AChE) inhibitor (IC 50  = 2.13 μM for electric eel AChE, 1.8 μM for ratAChE and 3.82 μM for human erythrocytes AChE), and the result of molecular docking provided an explanation for its selective BuChE inhibitory activity. Compound 7f also had noteworthy inhibitory effects on self-induced Aβ 1-42 aggregation (50.8 ± 0.82%) and was found to disaggregate self-induced Aβ 1-42 aggregation (38.7 ± 0.65%), which was further elucidated by the transmission electron microscopy. Meanwhile, compound 7f showed the modest antioxidant activity (0.55 eq of Trolox), good protective effect against H 2 O 2 -induced PC12 cell injury, with low toxicity. Moreover, compound 7f could cross the blood-brain barrier (BBB) in vitro. Significantly, compound 7f did not exhibit any acute toxicity in mice at doses up to 1000 mg/kg, and the step-down passive avoidance test showed this compound significantly reversed scopolamine-induced memory deficit in mice. Taken together, the results indicated that compound 7f is a very promising multifunctional agent in the treatment of Alzheimer's disease, particularly the advanced stages of AD., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

A Cp*Co III -catalyzed C2-selective C-H alkenylation/annulation cascade transformation of 1-(pyridin-2-yl)-1H-indoles with internal alkynes to afford pyrido[2',1':2,3]pyrimido[1,6-a]indol-5-iums is presented. Moreover, 6,7-dihydro-4H-pyrido[2',1':2,3]pyrimido[1,6-a]indole, a new functionalized N-fused indole core heterocycle, could be constructed effectively via reduction of pyrido[2',1':2,3]pyrimido[1,6-a]indol-5-ium by NaBH 4 .

A novel series of ferulic acid-memoquin hybrids were designed, synthesized and evaluated as multifunctional agents for the treatment of Alzheimer's disease (AD). The in vitro studies showed that most of the compounds exhibited a significant ability to inhibit acetylcholinesterase (AChE) (IC50 of 3.2-34.7μM) and self-induced β-amyloid (Aβ1-42) aggregation (30.8-39.1%, 25μM), to act as potential antioxidants (ORAC-FL value of 0.9-1.3). In particular, compound 17d had the greatest ability to inhibit AChE (IC50=3.2μM), and Aβ1-42 aggregation (30.8%) was also an excellent antioxidant and neuroprotectant. Moreover, it is capable of disaggregating self-induced Aβ aggregation. Furthermore, 17d could cross the blood-brain barrier (BBB) in vitro. The results showed that compound 17d is a potential multifunctional agent for the treatment of AD., (Copyright © 2016. Published by Elsevier Ltd.)

The first cobalt-catalyzed decarboxylative acetoxylation reaction was accomplished. This methodology is applicable to a wide range of amino acids and arylacetic acids.

A copper(II)-catalyzed tandem reaction between pyridine ketone and benzylamine was developed by using clean O2 as an oxidant. This transformation proceeded via an efficient condensation-amination-oxidative dehydrogenation process, affording 1,3-diarylated imidazo[1,5-a]pyridines in excellent yields.