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Two sensitive and effective methods were developed for the detection of catecholamines and related biogenic amines (dopamine, epinephrine, norepinephrine, serotonin, levodopa and tyramine) using high performance liquid chromatography with fluorescence detection and capillary electrophoresis with laser-induced fluorescence detection. A BODIPY fluorescent dye, 1, 3, 5, 7-tetramethyl-8-(N-hydroxysuccinimidyl propionic ester)-difluoroboradiaza- s-indacene was used as pre-column derivatization reagent. The separation and derivatization conditions were optimized in detail. In high performance liquid chromatography with fluorescence detection method, the derivatization reaction was completed at 35 °C for 20 min. At the wavelength of λ ex/λ em = 493 nm/513 nm, dopamine, epinephrine, norepinephrine, and levodopa derivatives achieved baseline separation within 15 min. The limits of detection (S/N = 3) were 1.0, 2.0, 5.0, and 0.5 nmol/L, respectively. In capillary electrophoresis with laser-induced fluorescence detection method, the derivatization reaction was completed at 25 °C for 20 min. Serotonin, tyramine and dopamine derivatives reached baseline separation within 10 min at the wavelength of λ ex = 473 nm. The limits of detection (S/N = 3) for serotonin, tyramine, and dopamine were 0.3, 0.02, and 0.2 nmol/L, respectively. The amino compounds in human serum and urine samples were detected successfully, and the recoveries were 93.3%–106.7% and 91.0%–103.1%, respectively.

Airborne fine particulate matter (PM2.5) is known to cause respiratory inflammation such as chronic obstructive pulmonary disease and lung fibrosis. NLRP3 inflammasome activation has been implicated in these diseases; however, due to the complexity in PM2.5 compositions, it is difficult to differentiate the roles of the components in triggering this pathway. We collected eight real-life PM2.5 samples for a comparative analysis of their effects on NLRP3 inflammasome activation and lung fibrosis. In vitro assays showed that although the PM2.5 particles did not induce significant cytotoxicity at the dose range of 12.5 to 100 µg/mL, they induced potent TNF-α and IL-1β production in PMA differentiated THP-1 human macrophages and TGF-β1 production in BEAS-2B human bronchial epithelial cells. At the dose of 100 µg/mL, PM2.5 induced NLRP3 inflammasome activation by inducing lysosomal damage and cathepsin B release, leading to IL-1β production. This was confirmed by using NLRP3- and ASC-deficient cells as well as a cathepsin B inhibitor, ca-074 ME. Administration of PM2.5 via oropharyngeal aspiration at 2 mg/kg induced significant TGF-β1 production in the bronchoalveolar lavage fluid and collagen deposition in the lung at 21 days post-exposure, suggesting PM2.5 has the potential to induce pulmonary fibrosis. The ranking of in vitro IL-1β production correlates well with the in vivo total cell count, TGF-β1 production, and collagen deposition. In summary, we demonstrate that the PM2.5 is capable of inducing NLRP3 inflammasome activation, which triggers a series of cellular responses in the lung to induce fibrosis.

The rational design and preparation of advanced electrocatalysts for the hydrogen evolution reaction (HER) under alkaline conditions is the key to achieving sustainable hydrogen production. Herein, a new type of nitrogen-doped porous carbon nanosheets (NPCN) loaded with platinum group metals (Pd, Pt or Ru) were prepared. The introduction of melamine not only realized the doping of N-species, but also optimized the morphology and surface functional groups of the prepared catalysts. The prepared Pd-NPCN, Pt-NPCN and Ru-NPCN with a metal loading of about 10 wt% showed outstanding HER activity (21, 9 and 11 mv at 10 mA cm−2 current density), small Tafel slopes (49, 30 and 30 mV dec−1) and good stability in 1.0 M KOH. In addition, the mechanism of the introduction of melamine to improve the catalytic performance of HER was also discussed. Therefore, this work provides promising alternatives to traditional Pt-based catalysts, and is instructive for the design of high-efficiency alkaline HER catalysts.

The development of recyclable photocatalyst with high adsorption and excellent photocatalytic performance has attracted considerable attention. Herein, we report a three-component photocatalyst by constructing porous amine functionalized zirconium metal organic framework (UiO-66-NH2) and broad photo-responsive AgI on flexible carbon fiber cloth (CFC). UiO-66-NH2 nanoparticles (200–400 nm) were in-situ grown on the surface of CFC (16.5 ± 0.5 μm, 4 × 4 cm2) by a solvothermal route, then AgI particles (50–100 nm) were synthesized on CFC/UiO-66-NH2 via a modified chemical bath deposition method. The obtained CFC/UiO-66-NH2/AgI can effectively adsorb 19.0% levofloxacin (LVFX) or 18.4% ciprofloxacin (CIP) in 60 min in the dark and degrade 84.5% LVFX or 79.6% CIP in 120 min under visible light irradiation. Furthermore, the filter-membrane-shaped CFC/UiO-66-NH2/AgI can be utilized to treat the flowing sewage (CIP, 10 mg/L, ~1 L/h), and the removing efficiency of CIP reached 71.0% after 10 grades. Therefore, this work demonstrates the huge application prospect of recyclable CFC/UiO-66-NH2/AgI with high adsorption and photocatalytic capacity in flowing sewage treatment under visible light illumination.

Background Long non-coding RNA (LncRNA) controls cell proliferation and plays a significant role in the initiation and progression of esophageal squamous cell carcinoma (ESCC). N6-methyladenosine (m6A) modification now is recognized as a master driver of RNA function to maintain homeostasis in cancer cells. However, how m6A regulates LncRNA function and its role in tumorigenesis of ESCC remain unclear. Methods Multiple ESCC datasets were used to analyze gene expression in tumor tissues and normal tissues. Kaplan-Meier method and the ROC curve were conducted to evaluate the prognostic value and diagnostic value of LINC00022 in ESCC, respectively. Both gain-of-function and loss-of-function experiments were employed to investigate the effects of LINC00022 on ESCC growth in vitro and in vivo. Bioinformatics analysis, colorimetric m6A assay, RIP, MeRIP and co-IP was performed to explore the epigenetic mechanism of LINC00022 up-regulation in ESCC. Results Here we report that m6A demethylation of LncRNA LINC00022 by fat mass and obesity-associated protein (FTO) promotes tumor growth of ESCC in vivo. Clinically, we revealed that LINC00022 was up-regulated in primary ESCC samples and was predictive of poor clinical outcome for ESCC patients. Mechanistically, LINC00022 directly binds to p21 protein and promotes its ubiquitination-mediated degradation, thereby facilitating cell-cycle progression and proliferation. Further, the elevated FTO in ESCC decreased m6A methylation of LINC00022 transcript, leading to the inhibition of LINC00022 decay via the m6A reader YTHDF2. Over-expression of FTO was shown to drive LINC00022-dependent cell proliferation and tumor growth of ESCC. Conclusions Thus, this study demonstrated m6A-mediated epigenetic modification of LncRNA contributes to the tumorigenesis in ESCC and LINC00022, specific target of m6A, serves as a potential biomarker for this malignancy.

Nitrogen-doped carbon materials with vacancies/defects have been developed as highly efficient ORR electrocatalysts but with poor activity for OER, which limits their application in rechargeable metal-air batteries. Filling the vacancies/defects with heteroatoms is expected to be an effective strategy to obtain surprising catalytic activities and improve their stability especially under the strongly oxidizing conditions during the OER process. Herein, we successfully transformed the defect-rich 3D carbon nanosheets (DCN) into a bifunctional ORR/OER electrocatalyst (DCN-M) by utilizing the in-situ generated vacancies to capture metal cations via a modified salt-sealed strategy. By varying the metal (Fe, Ni) content, the captured metal cations in DCN-M existed in different chemical states, i.e., metal atoms were stabilized by C−N bonds at low metal contents, while at high metal contents, bimetal particles were covered by graphene layers, taking responsibility for catalyzing the ORR and OER, respectively. In addition, the in-situ formed graphene layers with an interconnected structure facilitate the electron transport during the reactions. The Janus-feature of DCN-M in structures ensures superior bifunctional activity and good stability towards ORR/OER for the rechargeable Zn-air battery. This work provides an effective strategy to design multifunctional electrocatalysts by heteroatom filling into vacancies of carbon materials.

Low-concentration ethane capture is crucial for environmental protection and natural gas purification. The ideal physisorbent with strong C2 H6 interaction and large C2 H6 uptake at low-concentration level has rarely been reported, due to the large pKa value and small quadrupole moment of C2 H6 . Herein, we demonstrate the perfectly size matching between the ultramicropore (pore size of 4.6 A) and ethane (kinetic diameter of 4.4 A) in a nickel pyridine-4-carboxylate metal-organic framework (IISERP-MOF2), which enables the record-breaking performance for low concentration C2 H6 capture. IISERP-MOF2 exhibits the large C2 H6 adsorption enthalpy of 56.7 kJ/mol, and record-high C2 H6 uptake at low pressure of 0.01-0.1 bar and 298 K (1.8 mmol/g at 0.01 bar). Molecule simulations and C2 H6 -loading crystal structure analysis revealed that the maximized interaction sites in IISERP-MOF2 with ethane molecule originates the strong C2 H6 adsorption. The dynamic breakthrough experiments for gas mixtures of C2 H6 /N2 (1/999, v/v) and C2 H6 /CH4 (5/95, v/v) proved the excellent low-concentration C2 H6 capture performance.

A styrene-butadiene-styrene triblock copolymer (SBS) was grafted with an unsaturated polar monomer (monomer A) composed of maleic anhydride (MAH) and methoxy polyethylene (MPEG) via a ring-opening reaction after epoxidizing styrene-butadiene-styrene triblock copolymer (ESBS). The microscopic changes of SBS before and after grafting has been characterized with Fourier transform infrared spectrum (FT-IR), X-ray photoelectron spectroscopy (XPS) and gel permeation chromatography (GPC). The results revealed that the monomer A was successfully grafted on SBS backbone, and the maximum graft ratio (GR) was 20.32%. To verify the compatibility between SBS and asphalt, solubility parameters and surface free energy (SFE) of SBS, grafted SBS and asphalt were measured. It was found that the solubility parameter and SFE of grafted SBS were closer to asphalt compared with SBS. It also has been confirmed from storage stability that the temperature susceptibility of grafted SBS modified asphalt was reduced in compare with SBS modified asphalt binder. As consequence, the use of grafted copolymer can be considered a suitable alternative for modification of asphalt binder in pavement.

The N-methyl-D-aspartate receptor (NMDAR) in central nerve system is mostly composed of GluN1 and GluN2 subunits. The classical NMDAR has been intensively studied. However, GluN3‑containing NMDAR is much less expressed and have atypical channel properties. Recently, accumulating evidences have revealed two types of GluN3‑containing NMDAR: glutamate-gated GluN1/GluN2/GluN3 NMDAR and glycine-gated GluN1/GluN3 NMDAR. The former may play important roles in regulating synapse maturation and pruning non-used synapses, and its elevated expression at the adult stage may alter synaptic reorganization in some neuropsychiatric disorders. The latter is expressed in the medial habenula and involves in control of aversion. This article reviews the recent progresses on the expression, functional properties of GluN3‑containing atypical NMDARs and the physiological and pathological relevance.

In this work, the unique plastic deformation behavior of T2 rolled copper foils under ultrasonic impact (UI) and ultrasonic rolling (UR) has been studied systematically. The numerical simulation and test results show that with the decrease of the thickness of copper sheet, the equivalent plastic strain (PEEQ) value and plastic strain ep formed by UI or UR increase exponentially, and its distribution changes from gradient to uniform on the cross section, which is distinctive from the commonly observed gradient structure in ultrasonically treated bulk materials. Correspondingly, characterized by EBSD and TEM, the 100-μm-thick copper foil treated by UR shows the overall strengthening and forming a sub-micron grain structure with significant refinement and uniform distribution on the cross section. The microstructure homogenization of copper foil is attributed to the rigid wall effect facilitating the elastic-plastic stress wave bounce. The exponential increase of PEEQ and ep is explained as that with the decrease of the thickness of ultrasonic object, on the one hand, the acoustic softening and size effect which can reduce the elastic limit of copper foil are enhanced; on the other hand, the plastic deformation mode changes from stress superposition to dynamic impact. Through the establishment of a new theoretical model, the criterion of ultrasonic dynamic impact effect is deduced and verified by experiments.

s Ionic liquids (ILs)-solid interfacial phenomenon is undoubtedly one of the topic issues in energy related fields, especially bringing great challenges in the development of chemical engineering. Solid-ILs friction under microscale shows outstanding properties such as widely studied electro-controllability by surface potential or electric field, and promising performance of superlubricity. Vast applications, such as boundary lubrication and supercapacitors, have been benefiting from these studies. In this review, we summarized the recent advances of the measurements of solid-ILs friction, and focused on the microscale and fascinating findings. A brief tutorial for this topic, containing both experimental and theoretical methods, was also provided. It was anticipated that this review would help researchers grasp the emerging field and stimulate the advance of new ideas and methods in ILs on solids.

Carbon nanomaterials are ideal fillers in composites for electrothermal applications due to their ultrahigh electrical conductivity, thermal conductivity, and excellent mechanical property. In this study, high-performance electrothermal laminate films were prepared by a layer-by-layer process, which used tannic acid-functionalized multiwalled carbon nanotubes as filler and thermoplastic polyurethane as substrate. The prepared electrothermal laminate films exhibit excellent mechanical property, electrical heating property, and high electrothermal performance, which can reach steady-state temperature in about 120 s. Additionally, the maximum steady-state temperature can reach ∼150 °C at 20 V. During 10 different cycles of experiments and 5 h aging time, no significant change in temperature was observed. Moreover, from the results, it is clear that the performance of the samples is related to the amount of filler added and the applied voltage, and we can precisely control the sample performance by regulating the amount of filler addition and applied voltage. We believe that these electrothermal laminate films could be widely used in wearable heating cotton fabric, controllable electric heating module, floor heating, and deicing devices.

Multiple studies have showed that berberine protects against heart diseases, including obesity-associated cardiomyopathy. However, it is not fully disclosed the potential molecular mechanisms of berberine on controlling cardiac remodeling. Kruppel-like factor (KLF) 4, identified as a critical transcriptional factor, participates in multiple cardiac injuries. The present study was to explore whether KLF4 determined the cardioprotective benefits of berberine in dietary-induced obese mice. High fat diet-induced obese mice were treated with berberine with or without lentivirus encoding Klf4 siRNA, and cardiac parameters were analyzed by multiple biological approaches. In dietary-induced obese mouse model, administration of berberine obviously increased cardiac level of KLF4, which closely correlated with improvement of cardiac functional parameters. Co-treatment of lentivirus encoding Klf4 siRNA abolished cardioprotective benefits of berberine, including induction of cardiac hypertrophy, fibrosis, functional disorders, inflammatory response and oxidative stress. Mechanistically, we found berberine improved cardiac mitochondrial biogenesis and activities, whereas silencing Klf4 decreased berberine-upregulated mitochondrial quality, ATP production and oxygen consumption. Our present study demonstrated that berberine protected against dietary-induced cardiac structural disorders and mitochondrial dysfunction dependent on cardiac KLF4 signaling. Cardiac KLF4 was one of potential therapeutic targets for obesity-induced cardiac injuries.

The joint behavior of internal and external system brings out a high complexity of the carbon and oil price interactions, such as non-linearity and multi-frequency. This paper innovatively proposed a time-frequency mechanism between carbon and oil markets from the two aspects of internal system and external factors, and introduced a novelty partial wavelet analytics to explore their dynamic multi-scale interactions. We selected the European carbon and Brent oil futures prices data from March 2009 to December 2020, with the consideration of several necessary control variables from the external surroundings. Our findings point to a stable and strong in-phase relationship between the two markets, with oil leading at medium and lower frequencies. However, the mutual leading relationships are especially sensitive during abnormal political events and periods of financial recession and global emergency, which are observed at different periods for intermediate horizons. What is more, the interactions are more diversified and feebler at short-timescale. Under the vision of carbon neutrality, these evidences provide invaluable guidance for regulators to structure a more flexible adjusting mechanism for the risk control of carbon markets, and also help investors to hedge risk aimed at different time horizons.

Niobate perovskites like the (K,Na)NbO3 (KNN) family are among the most important lead-free ferroelectrics. Ba and Ni have been co-doped into KNN to induce Ni2+-oxygen vacancy defect dipoles to significantly reduce the band gap while maintaining the ferroelectricity. This opens doors to novel optoferroelectric applications such as multisensors and photocatalysts. However, obtaining a single phase of the above co-doped KNN is difficult due to the sensitive stoichiometry on phase formation and arduous nickel diffusion into the KNN unit cells during synthesis. This paper reports an alternative approach to simultaneously tune the band gap and ferroelectricity. A-site vacancies are intentionally introduced into the mixtures of starting reactants. The homogeneously distributed vacancies trigger self-assembly of a niobate perovskite and niobate tungsten bronze phase and thus form a composite. The interface between the two phases, which mimics a heterojunction, rather than any individual phase, is proven to be responsible for the resultant narrow band gap and strong ferroelectricity. Hypotheses are proposed based on the results of ferroelectric, photoconductivity, and density functional theory-based studies to explain the mechanism. This paper offers an additional option to engineer polarizations and band structures in complex photoferroelectric oxides, especially alkaline niobates.

Fumonisin B1 (FB1), as the most toxic fumonisin, is a common Fusarium mycotoxin contaminant of feed stuff and food, posing a potential health hazard to animals and humans. FB1 has been reported to cause hepatotoxicity, neurotoxicity, nephrotoxicity, immunotoxicity and embryotoxicity; however, little information is available on whether FB1 has toxic effects on mammalian oocytes. Herein, we adopted porcine oocytes as models to explore the effects and potential mechanisms of FB1 on mammalian oocytes during in vitro maturation. Porcine cumulus oocyte complexes (COCs) were exposed to 0, 20, 30 and 40 μM FB1 for 44 h during in vitro maturation, and the results reported that first polar body (PB1) extrusion was significantly inhibited when the FB1 concentration reached 30 (P

The incorporation of aluminum (Al) into explosives represents a facility and efficient way to enhance the energy output through the secondary reaction between Al and the detonation products of explosive. The Al/O ratio and microstructure of HMX/Al play critical roles in combustion performance and energy output. Herein, a gradient structured HMX/Al composite has been designed and fabricated via 3D printing technology using well-dispersed HMX/Al-based ink. For HMX/Al lines, the second reaction heat increases from 196.5 J/g to 1644.8 J/g and the burning rate would decrease from 14.6 to 12.0 mm/s with Al content increased from 10 to 30 wt%. For gradient structured HMX/Al, the burning rate could be controlled by varying the component ratio and the burning rate of each component in the gradient structure was higher than that of the normal HMX/Al counterpart. Furthermore, a gradient evolution of pressure output was monitored for gradient structured HMX/Al cylinder ignited by the laser. These results indicate that the gradient structure as an effective approach can tune combustion performance and energy output of HMX/Al.

Honey maturity is an important factor in evaluating the quality of honey; however, there are few studies on the molecular mechanism of the formation of mature honey (MH). In this study, the different metabolites of stomach honey (SH), immature honey (IMH), and MH samples during the same rapeseed flower season were analyzed by an UPLC-QTOF-MS-based metabolomics approach. MH was found to have a distinct metabolic profile to IMH, and a total of 9 different metabolites were obtained, 3 of which, including decenedioic acid, were accumulated in MH. Decenedioic acid as a bee-originated fatty acid (FA) was further verified in rape, acacia, and jujube honey by GC-MS, making it a potential marker to discriminate IMH and MH (P < 0.01). Besides, MH showed higher FAs concentrations; in particular, 3 FAs were significantly richer in MH than IMH (P < 0.05). This study reveals the molecular mechanism from IMH to MH from a FA perspective.

Liver fibrosis is a pathological process characterized by excess deposition of extracellular matrix (ECM) that are mainly derived from activated hepatic stellate cells. Previous studies suggested that ligustroflavone (LF) was an ingredient of Ligustrum lucidum Ait. with activities of anti-inflammation and anti-oxidation. In this study, we investigated whether LF had any effect on liver fibrosis. In our study, we established a mouse model of carbon tetrachloride (CCl4)-induced liver fibrosis and used TGF-β1-stimulated human hepatic stellate cell line (LX-2) to explore the effect of LF and associated underlying mechanism. LF was used in vivo with low dose (L-LF, 5 mg·kg-1, i.p., 3 times each week) and high dose (H-LF, 20 mg·kg-1, i.p., 3 times each week) and in vitro (25 μmol·L-1). Histopathological and biochemical assays investigations showed that LF delayed the formation of liver fibrosis; decreased AST, ALT activities and increased Alb activity in serum; decreased MDA level, Hyp content and increased GSH-Px concentration, SOD activity in liver tissues. Moreover, immunohistochemical, immunofluorescent and Western blot results showed that LF reduced the expressions of hepatic stellate cells specific marker proteins, including collagen I and α-SMA in vivo and in vitro. In addition, LF markedly suppressed TGF-β1-upregulated protein expressions of TβR I, TβR II, P-Smad2, P-Smad3 and Smad4 in LX-2 cells. Taken together, these findings demonstrated LF could decrease histopathological lesions, ameliorate oxidative injury, attenuate CCl4-induced liver fibrosis, which may be associated with down-regulating the TGF-β/Smad signaling pathway.

Lei Sheng,1,* Wei Cao,2,* Pingping Lin,3 Weili Chen,1 Hongrong Xu,1 Chunjiu Zhong,4 Fei Yuan,1 Hanjing Chen,1 Hui Li,1 Chao Liu,1 Mengjie Yang,1 Xuening Li1 1Department of Clinical Pharmacology, Zhongshan Hospital, Fudan University, Shanghai, 200032, People’s Republic of China; 2Shanghai Rixin Biotechnology Co., Ltd, Shanghai, 200237, People’s Republic of China; 3Phase I Clinical Research Center, The Affiliated Hospital of Qingdao University, Shandong, 266071, People’s Republic of China; 4Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, 200032, People’s Republic of China*These authors contributed equally to this workCorrespondence: Xuening LiDepartment of Clinical Pharmacology, Zhongshan Hospital, Fudan University, 180 FengLin Road, Shanghai, 200032, People’s Republic of ChinaTel +86 21 3158 7860Fax +86 21 6443 7963Email li.xuening@zs-hospital.sh.cnPurpose: Safety, tolerability and pharmacokinetics of single and multiple ascending doses (SADs/MADs) of benfotiamine were assessed after oral administration in two randomized, double-blind, placebo-controlled, phase I trials.Methods: Healthy subjects were sequentially enrolled into one of five SAD (150– 1200 mg) or three MAD (150, 300 or 600 mg) cohorts. In SAD study, each cohort of 12 subjects (n = 10, active; n = 2, placebo) were administrated once-daily doses. In MAD study, each cohort of 16 subjects (n = 12, active; n = 4, placebo) were administrated once-daily on day 1 and twice-daily on day 4– 9, followed by a single morning dose on day 10.Results: In the SAD study, the median time to reach maximum concentration (Tmax) arrived 1.0 to 2.0 h for thiamine (TM), 3.5 to 8.0 h for thiamine monophosphate (TMP), and 8.0 to 24.0 h for thiamine diphosphate (TDP) after administration of benfotiamine. The area under concentration-time curve from 0 to last measurable concentration (AUC0-t) or maximum observed concentration (Cmax) of TM, TMP, and TDP was less or more dose proportional over the single dose studied except Cmax of TM. Food consumption did not increase the level of TM and TDP at baseline. TM exhibited a relatively long elimination half-life (t1/2) in all doses studied, resulting in accumulation ratio (Rac) of 1.96 to 2.11 and accumulation ratio based on Cmax (Rac, Cmax) of 1.60 to 1.88 following 7 days of multiple dosing. Comparable accumulation results were also obtained for TDP after multiple dosing. The incidence and severity of adverse events (AEs) were similar between benfotiamine and placebo. The commonly reported drug-related AEs were increased ALT and urinary WBC.Conclusion: Both SAD and MAD studies of benfotiamine in healthy subjects were safe and well tolerated. TM and TDP exhibited moderate accumulation on repeated administration of benfotiamine.Keywords: Alzheimer’s disease, benfotiamine, thiamine, thiamine diphosphate, pharmacokinetics

Melanin is ubiquitous in living organisms across different biological kingdoms of life, making it an important, natural biomaterial. Its presence in nature from microorganisms to higher animals and plants is attributed to the many functions of melanin, including pigmentation, radical scavenging, radiation protection, and thermal regulation. Generally, melanin is classified into five types-eumelanin, pheomelanin, neuromelanin, allomelanin, and pyomelanin-based on the various chemical precursors used in their biosynthesis. Despite its long history of study, the exact chemical makeup of melanin remains unclear, and it moreover has an inherent diversity and complexity of chemical structure, likely including many functions and properties that remain to be identified. Synthetic mimics have begun to play a broader role in unraveling structure and function relationships of natural melanins. In the past decade, polydopamine, which has served as the conventional form of synthetic eumelanin, has dominated the literature on melanin-based materials, while the synthetic analogues of other melanins have received far less attention. In this perspective, we will discuss the synthesis of melanin materials with a special focus beyond polydopamine. We will emphasize efforts to elucidate biosynthetic pathways and structural characterization approaches that can be harnessed to interrogate specific structure-function relationships, including electron paramagnetic resonance (EPR) and solid-state nuclear magnetic resonance (ssNMR) spectroscopy. We believe that this timely Perspective will introduce this class of biopolymer to the broader chemistry community, where we hope to stimulate new opportunities in novel, melanin-based poly-functional synthetic materials.

In this work, a band insertion strategy by 7,7,8,8-tetracyanoquinododimethane (TCNQ) loading is applied to modulate the band gap of a ruthenium metal–organic framework, [Ru3(btc)2Cl1.5] (btc = 1,3,...

The impact of the policy of coal-fired reduction and clean energy growth promoted in Beijing, China, during the 12th and 13th Five-Year Plan Period (2011–2020) on polycyclic aromatic hydrocarbons (...

Ethylene production from C2 hydrocarbon mixtures through one separation step is desirable but challenging because of the similar size and physical properties of acetylene, ethylene, and ethane. Herein, we report three new isostructural porous coordination networks (NPU-1, NPU-2, NPU-3; NPU represents Northwestern Polytechnical University) that are sustained by 9-connected nodes based upon a hexanuclear metal cluster of composition [Mn6(μ3-O)2(CH3COO)3]6+. NPU-1/2/3 exhibit a dual cage structure that was systematically fine-tuned in terms of cage size to realize selective adsorption of C2H2 and C2H6 over C2H4. Dynamic breakthrough experiments demonstrated that NPU-1 produces ethylene in >99.9% purity from a three-component gas mixture (1:1:1 C2H2/C2H4/C2H6). Molecular modeling studies revealed that the dual adsorption preference for C2H2 and C2H6 over C2H4 originates from (a) strong hydrogen-bonding interactions between electronegative carboxylate O atoms and C2H2 molecules in one cage and (b) multiple non-covalent interactions between the organic linkers of the host network and C2H6 molecules in the second cage.

Bifunctional squaramide-catalyzed nucleophilic addition of thiophenols to easily available β-silyl α,β-unsaturated carbonyl compounds has been successfully developed. A structurally diverse set of chiral α-mercaptosilanes was efficiently prepared in good to excellent yields with acceptable enantioselectivities. The reaction features mild reaction conditions, a broad substrate scope, and easy scale-up.

Herein, a label-free electrochemical immunosensor based on differential pulse voltammetry (DPV) and amperometric i-t curve (i-t) dual-mode analysis is proposed for early quantitative detection of procalcitonin (PCT). Due to the advantages of high chemical stability and biocompatibility, graphite carbon nitride (g-C3N4) was adopted as a high-capacity sensing interface to carry signal indicators. As an effective indicator of chronoamperometry, nickel cobalt sulfide (NiCo2S4) was uniformly dispersed on the surface of g-C3N4 through in-situ hydrothermal synthesis, which not only promotes the activation of bimetallic activity, but also effectively prevents the aggregation of NiCo2S4. At the same time, in order to establish a dual-mode analysis platform to improve accuracy and sensitivity, highly conductive carbon nanotubes (CNTs) were hybridized with composite materials to load Ag nanoparticles (Ag NPs), which have excellent oxidizing properties and are used as indicators of DPV. On account of this advanced sensing strategy, a wide linear response (DPV: 0.05 ng mL-1-50 ng mL-1 and i-t: 1.00 pg mL-1-10.00 ng mL-1) and a low detection limit (DPV: 16.70 pg mL-1 and i-t: 0.33 pg mL-1) are demonstrated. The immunosensor synthesized by this method has good stability and sensitivity, which could be applied in clinical diagnosis and treatment.

Both imidazolium and 1,2,4-triazolium cations are important functional moieties widely incorporated as building blocks in poly(ionic liquid)s (PILs). In a classical model, a PIL usually contains either imidazolium or 1,2,4-triazolium in its repeating unit. Herein, via exploiting the slight reactivity difference of alkyl bromide with imidazole and 1,2,4-triazole at room temperature, we synthesized dual-cationic PIL homopolymers carrying both imidazolium and 1,2,4-triazolium moieties in the same repeating unit, that is, an asymmetrically dicationic unit. We investigated their fundamental properties, for example, thermal stability and solubility, as well as their unique function in forming supramolecular porous membranes via a water-initiated phase-separation and cross-linking process. With such knowledge, we identified a water-based fabricate strategy toward air-stable porous membranes from single-component PILs. This study will enrich the design tools and chemical structure library of PILs and expand their application spectrum.

Immunoglobulin G (IgG) molecules modulate an immune response. However, site-specific N-glycosylation signatures of plasma IgG in patients with chronic kidney disease (CKD) remain unclear. This study aimed to propose a novel method to explore the N-glycosylation pattern of IgG and to compare it with reported methods. We separated human plasma IgG from 58 healthy controls (HC) and 111 patients with CKD. Purified IgG molecules were digested by trypsin. Tryptic peptides without enrichment of intact N-glycopeptides were analyzed using a combination of electron-transfer/higher-energy collisional dissociation (EThcD) and stepped collision energy/higher-energy collisional dissociation (sceHCD) mass spectrometry (EThcD-sceHCD-MS/MS). This resulted in higher spectral quality, more informative fragment ions, higher Byonic score, and nearly twice the depth of intact N-glycopeptide identification than sceHCD or EThcD alone. Site-specific N-glycosylation mapping revealed that intact N-glycopeptides were differentially expressed in HC and CKD patients; thus, it can be a diagnostic tool. This study provides a method for the determination of glycosylation patterns in CKD and a framework for understanding the role of IgG in the pathophysiology of CKD. Data are available via ProteomeXchange with identifier PXD027174.

Background The plasma concentration of patients treated with efavirenz (EFV) 600 mg was found to exceed the upper limit of the proposed therapeutic window in most Chinese HIV-infected individuals; thus, dosage reduction of EFV to 400 mg daily warranted consideration. This study aimed to assess the pharmacodynamics of EFV 400 mg for HIV-1-infected patients in China. Method Twenty cART-naïve individuals were enrolled in this study. EFV 400 mg combined with tenofovir (TDF) and lamivudine (3TC) as an initial antiretroviral regimen was administered for 48 weeks. EFV concentration and T cell subsets as well as HIV RNA load were evaluated at baseline and at 4, 12, 24, and 48 weeks. Moreover, neuropsychiatric adverse effects were also assessed by the Hamilton depression (HAMD) scale and Pittsburgh sleep quality index (PSQI). Results Eighteen males and two females whose median age was 26 (interquartile range [IQR]: 23–32) years completed 48 weeks of follow-up. The median EFV concentrations were 1.88 (IQR: 1.54–2.42), 1.74 (IQR: 1.36–1.93), 1.93 (IQR: 1.66–2.22), and 1.85 (IQR: 1.54–2.14) mg/L at weeks 4, 12, 24, and 48, respectively. The viral load was 4.59 (IQR: 4.10–5.19) log10 copies/mL at baseline, and it decreased by 4.6 (IQR: 3.98–5.18) log10 copies/mL from baseline to week 48. Three of 20 (15%), 10 of 20 (50.0%), 17 of 20 (85%), and 18 of 19 (95%) participants had a plasma viral load less than 50 copies/mL at weeks 4, 12, 24, and 48, respectively. The median CD4 cell count was 330 (IQR: 237–410) cells/μL at baseline, and it increased to 473 (IQR: 344–574) cells/μL at 48 weeks. The HAMD score was 5 (IQR: 3–9.8) and 3 (IQR: 2.25–4) at baseline and 48 weeks, respectively. The PSQI score was 4 (IQR: 2–5.8) and 3 (IQR: 2–4) at baseline and 48 weeks, respectively. Dizziness was the most common event, occurring in 70% of patients within the first 2 weeks of treatment. Conclusion Patients prescribed with EFV 400 mg-containing agents demonstrated favourable virological and immunological responses. And the plasma EFV concentration was within the recommended therapeutic range, with fewer adverse reactions than with EFV 600 mg. EFV 400 mg was effective and safe in Chinese HIV-infected patients. Trial registration NCT04596488; Registered 21 October, 2020; Retrospectively registered.

N-Heterocyclic carbene-catalyzed [3 + 3] annulation of bromoenals with 2-aminochromones has been successfully developed. A structurally diverse set of chromeno[2,3-b]pyridinones was efficiently constructed in acceptable to excellent yields. The reaction features mild reaction conditions, a broad substrate scope, and easy scale-up.