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MoS2 has been explored as a potential material for hydrogen evolution reaction (HER) and lithium-ion batteries (LIBs). However, the limited number of active sites and poor conductivity restrain its applications. Herein, a facile method is reported to construct MoS2 nanosheets (MoS2 NSs) grown on agar-derived 3D nitrogen-doped porous carbon (MoS2-NPC). The as-prepared MoS2-NPC composite exhibits good stability and HER electrocatalytic properties with a low overpotential of 209 mV at 10 mA cm−2 and a small Tafel slope of 41 mV dec−1. Furthermore, as an anode of LIBs, it delivers an initial discharge capacity of 1289 mAh g−1 at 0.1 A g−1 and rate capability of 712 and 419 mAh g−1 at 0.5 and 2.0 A g−1, respectively. This is attributed to the synergistic effects and unique 3D network structure, which avoids the aggregation of MoS2 and results in more exposed active sites. The agar-derived 3D nitrogen-doped porous carbon can act as a support material for MoS2 NSs dispersed on the surface, providing a cheap and efficient strategy to prepare high quality catalysts for electrochemical energy conversion and storage applications., This work was financially supported by the National Natural Science Foundation of China (Nos. U1764254 and 21911530255), 111 Project, China (No. D17003), Graphene Flagship (881603), and the Open Research Fund of the State Key Laboratory of Inorganic Synthesis and Preparative Chemistry (Jilin University, Grant No. 2021-03).

TMCA (3,4,5-trimethoxycinnamic acid) ester and amide are privileged structural scaffolds in drug discovery which are widely distributed in natural products and consequently produced diverse therapeutically relevant pharmacological functions. Owing to the potential of TMCA ester and amide analogues as therapeutic agents, researches on chemical syntheses and modifications have been carried out to drug-like candidates with broad range of medicinal properties such as antitumor, antiviral, CNS (central nervous system) agents, antimicrobial, anti-inflammatory and hematologic agents for a long time. At the same time, SAR (structure-activity relationship) studies have draw greater attention among medicinal chemists, and many of the lead compounds were derived for various disease targets. However, there is an urgent need for the medicinal chemists to further exploit the precursor in developing chemical entities with promising bioactivity and druggability. This review concisely summarizes the synthesis and biological activity for TMCA ester and amide analogues. It also comprehensively reveals the relationship of significant biological activities along with SAR studies., Graphical abstract Image 1, Highlights • 3,4,5-Trimethoxycinnamic acid (TMCA) derivatives show applications in different pathophysiological conditions due to its privileged structural scaffolds. • Natural derived TMCA analogues and chemically modified TMCA ester and amide analogues and their bioactivities are focused in this review. Additionally, it also comprehensively summarized the relationship of significant biological activities along with SAR studies of synthetic TMCA derivatives.

The total synthesis of putative penasulfate A was effectively achieved by a convergent strategy with a longest linear sequence of 14 steps and overall yield of 8.6%. The highlights of our strategy involved an E-selective olefin cross-metathesis, Suzuki cross-coupling, and a copper(I)-catalyzed coupling reaction.

Glycyrrhetinic acid (GA) is a major constituent of the herb Glycyrrhiza glabra, and many of its derivatives demonstrate a broad spectrum of antiviral activities. In the current study, 18 water-soluble β-cyclodextrin (CD)-GA conjugates, in which GA was covalently coupled to the primary face of β-CD using 1,2,3-triazole moiety along with varying lengths of linker, were synthesized via copper-catalyzed azide-alkyl cycloaddition reaction. Benefited from the attached β-CD moiety, all these conjugates showed lower hydrophobicity (AlogP) compared with their parent compound GA. With the exception of per-O-methylated β-CD-GA conjugate (35), all other conjugates showed no significant cytotoxicity to MDCK cells, and these conjugates were then screened against A/WSN/33 (H1N1) virus using the cytopathic effect assay. The preliminary results indicated that six conjugates showed promising antiviral activity, and the C-3 and C-30 of GA could tolerate some modifications. Our findings suggested that GA could be used as a lead compound for the development of potential anti-influenza virus agents., Graphical abstract Image 1, Highlights • Triterpene natural products are proposed as a new class of compounds for blocking influenza virus entry. • A total of 18 β-cyclodextrin-glycyrrhetinic acid conjugates were designed and synthesized via click chemistry. • The structure-activity relationship of their anti-influenza A/WSN/33 (H1N1) viruses was summarized.

It is urgently necessary to develop more effective anti-influenza agents due to the continuous emergence of drug-resistant strains of influenza virus. Our earlier studies have identified that certain pentacyclic triterpene derivatives are effective inhibitors of influenza virus infection. In the present study, a series of C-28 modified pentacyclic triterpene derivatives via conjugation with a series of polyphenols were synthesized, and their antiviral activities against influenza A/WSN/33 (H1N1) virus in MDCK (Madin-Darby canine kidney) cells were evaluated. Four compounds 23m, 23o, 23q and 23s displayed robust anti-influenza potency with averaged IC50 values at the low-micromole level, surpassing the potency of oseltamivir. In addition, the in vitro cytotoxic activity of the four conjugates against MDCK cells showed no toxicity at 100 μM. Further mechanism studies of compound 23s, one of the best representative conjugates with IC50 value of 5.80 μM and a selective index (SI) value of over 17.2, by hemagglutination inhibition (HI), surface plasmon resonance and molecular modeling indicated that this conjugate bound tightly to the viral envelope hemagglutinin (KD = 15.6 μM), thus blocking the invasion of influenza viruses into host cells.

The first total synthesis of wikstrol A and wikstrol B was achieved via Sharpless asymmetric dihydroxylation, Sonogashira and rhodium-catalyzed oxidative coupling as key steps. , The first total synthesis of wikstrol A and wikstrol B was achieved by employing aldol reaction, Sharpless asymmetric dihydroxylation, regioselective iodination, Sonogashira coupling, and rhodium-catalyzed oxidative coupling as key steps. The structure of the key intermediate for wikstrol A was confirmed via its derivative by single-crystal X-ray analysis.

Objectives: This study examined the moderation of an oxytocin receptor (OXTR) gene in the link between childhood adversity and depressive symptoms among incarcerated males. Methods: Questionnaires about adverse childhood experiences and depressive symptoms, as well as genomic DNA from blood were collected among 608 incarcerated males (Mage = 32.4 years, SD = 9.41, 18–74 years). Moderation analysis was applied to examine the interaction between adverse childhood experiences (including abuse, neglect, and household dysfunction) and the OXTR polymorphisms (rs2254298, rs53576) in predicting depressive symptoms. Results: Incarcerated males had relatively higher prevalence of childhood adversity (70.2%) and depressive symptoms (49.8%). Higher childhood adversity was associated with increased depressive symptoms, and the effect was more pronounced in the GG homozygotes of OXTR rs2254298 (b = 0.406, p < .001), as compared with the AA/AG carriers (b = 0.236, p < .001). By contrast, the OXTR rs53576 did not interact with childhood adversity in predicting depressive symptoms. Conclusions: Chinese incarcerated males with the GG genotype of OXTR rs2254298 have higher vulnerability in the effect of childhood adversity on depressive symptoms. Accepted version

Glycans expressed on the forefront surface of cells participate in many key biological processes via forming various glycoconjugates. The recognition of complex glycoconjugates as mediators of important biological processes has stimulated investigation into their therapeutic potential. As the increasing accessibility of glycoconjugates, it has been widely applied in the field of drug delivery. This review particularly refers to the constitutive glycoconjugates of receptor-mediated binding of glycoprotein, glycolipids and glycopeptides for cell-selective drug delivery, in order to broaden the future therapeutic scope of drug delivery system and effective cancer therapy.

International audience; Face anti-spoofing is vital to the security of face recognition. Previous methods rely on hand-crafted features or use estimate depth map as supervision in CNNs and result in poor performance. In this paper, we propose a novel auto-encoder image reconstruction model to address the face anti-spoofing problem. In our model, we introduce the multi-scale skip connections to excavate multi-level semantics contained in images. Further, we combine the SSIM loss and Ll loss to guide the network towards better reconstruction results. We verify the effectiveness of our model design on OULU-NPU and SiW datasets and obtain promising results.

A new glycoside, named as CG-1, was separated from Imperial Chrysanthemum with silica gel column chromatography. The purity was detected by TLC and HPLC. The crystal shape of CG-1 was consisting of a quadrangular and two rectangular pyramids. The analysis of DSC and TGA showed that the melting point of CG-1 crystal was 150.22 °C and had good thermal stability. The monosaccharide conformation analysis showed that it was d-glucose. The structure characteristics were compared by FT-IR, NMR spectroscopy and LC-MS and a molecular structure has been deduced which consistent with spectroscopic results. In vitro antioxidant results suggested that the glycoside extracted from Imperial Chrysanthemum could be effectively employed as natural antioxidant in health or functional food. This work is of significance to keep the antioxidant activity in the processing and application of Imperial Chrysanthemum.

Gentiopicroside isolated from gentiana macrophylla Pall. belongs to iridoid glycosides. This study aimed to evaluate the protective effect of gentiopicroside against ethanol-induced gastric mucosal injury in mice. Mice were proactively administrated with gentiopicroside by intragastric administration once a day for 3 consecutive days. On the 3rd day, gastric ulcer in mice was induced with 70% ethanol after the last intragastric administration. The stomach tissues were submitted for evaluation of the severity of gastric mucosal alterations. Gentiopicroside administrated orally ameliorated the severity of gastric mucosal alterations. Oral administration of gentiopicroside significantly increased heat shock protein-70 and glutathione levels and superoxide dismutase activity, normalized epidermal growth factor and vascular endothelial growth factor levels, and decreased the levels of tumour necrosis factor-α, interleukin-6 and malondialdehyde, and myeloperoxidase activity in gastric tissue. These findings demonstrated that gentiopicroside has protective effect against ethanol-induced gastric mucosal injury in mice through the improvements of antioxidative and anti-inflammatory effects, as well as up-regulation of heat shock protein-70 level and normalization of epidermal growth factor and vascular endothelial growth factor levels. The results presented in this study provide some evidence for the development of a novel antigastric ulcer agent.

Historical geological and climatic events are the most important drivers of population expansions/contractions, range shifts, and interspecific divergence in plants. However, the species divergence and spatiotemporal population dynamics of alpine cold-tolerant herbal plants in the high-altitude Qinghai-Tibetan Plateau (QTP) and adjacent areas remain poorly understood. In this study, we investigated population evolutionary history of four endangered Notopterygium herb species in the QTP and adjacent regions. We sequenced 10 nuclear loci, 2 mitochondrial DNA regions, and 4 chloroplast DNA regions in a total of 72 natural populations from the 4 species, and tested the hypothesis that the population history of these alpine herbs was markedly affected by the Miocene–Pliocene QTP uplifts and Quaternary climatic oscillations. We found that the four Notopterygium species had generally low levels of nucleotide variability within populations. Molecular dating and isolation-with-migration analyses suggested that Notopterygium species diverged ~1.74–7.82 million years ago and their differentiation was significantly associated with recent uplifts of the eastern margin of the QTP. In addition, ecological niche modeling and population history analysis showed that N. incisum and N. franchetii underwent considerable demographic expansions during the last glacial period of the Pleistocene, whereas a demographic contraction and a expansion occurred for N. forrestii and N. oviforme during the antepenultimate interglacial period and penultimate glacial period, respectively. These findings highlight the importance of geological and climatic changes during the Miocene–Pliocene and Pleistocene as causes of species divergence and changes in population structure within cold-tolerant herbs in the QTP biodiversity hotspot., This work was co-supported by the National Natural Science Foundation of China (31470400), the Shaanxi Provincial Key Laboratory Project of Department of Education (grant number 17JS135), and the Open Foundation of Key Laboratory of Resource Biology and Biotechnology in Western China (Ministry of Education) (Number ZSK2017007).

An acid polysaccharide, named R-PL, was extracted from rose buds by hot water (80 °C) extraction and purified by Sephadex G-200. R-PL, extracted with a total yield of 1.90%, is a highly pure polysaccharide with a total sugar content of 92.51%. A single and symmetrically sharp peak in its high-performance gel-permeation chromatography (HPGPC) spectrum indicates that R-PL is a homogeneous polysaccharide with a molecular weight of 7.727 × 105 Da. Monosaccharide composition analysis shows that it consists of D-arabinose, D-xylose, D-glucose, D-galactose, D-galacturonic acid, and D-glucuronic acid with a molar ratio of 4.6 : 1.4 : 5.22 : 4.81 : 1 : 1.86. Structure analysis, such as FTIR spectroscopy, periodic acid oxidation, Smith degradation, methylation, and NMR analysis, reveals that R-PL has a backbone of →1)-α-D-Glcp-(6→ with side chains of →1)-β-D-Galp-(4,6→, →1)-β-D-Araf-(5→, →1)-α-D-Xylp-(4→, →1)-α-D-GlcpA-(2→ and →1)-α-D-GalpA-(4→. Its morphological characteristics were identified by Congo red experiments and scanning electron microscopy (SEM) analysis. The results show that R-PL does not have a triple-helical conformation in solution; its shape resembles twisted ribbons. Anti-oxidative and anti-aging analyses show that R-PL has significant antioxidant and anti-aging abilities in vivo.

Alantolactone and isoalantolactone isolated from many species of plants are a pair of positional isomers of CC bond. Previously, alantolactone and isoalantolactone have been proved to be good lead compounds for future anticancer agent development. Similarity of their molecular structures increases the separation difficulty for these two isomers on a conventional C18 column. Silver perchlorate (AgClO4) as mobile phase additives with RP-HPLC for improving the separation was developed for rapid determination of the positional isomers in Inula racemosa Hook.f. The effects of the concentration of silver perchlorate on the separation of the analytes were investigated. The composition of acetonitrile and water containing 5.0% silver perchlorate in a 65:35 (v/v) ratio was used as mobile phase, in which they were well separated within a short period of time on the C18 column. The method was successfully applied to determine them in an extract of Inula racemosa Hook.f. root. Silver perchlorate in mobile phase can efficiently improve the separation of the positional isomers and could be applied to rapidly determinate their content in this plant.

Loss of E-cadherin marks a defect in epithelial integrity and polarity during tissue injury and fibrosis. Whether loss of E-cadherin plays a causal role in fibrosis is uncertain. α3β1 Integrin has been identified to complex with E-cadherin in cell-cell adhesion, but little is known about the details of their cross talk. Herein, E-cadherin gene ( Cdh1 ) was selectively deleted from proximal tubules of murine kidney by Sglt2Cre . Ablation of E-cadherin up-regulated α3β1 integrin at cell-cell adhesion. E-cadherin–deficient proximal tubular epithelial cell displayed enhanced transforming growth factor-β1–induced α-smooth muscle actin (α-SMA) and vimentin expression, which was suppressed by siRNA silencing of α3 integrin, but not β1 integrin. Up-regulation of transforming growth factor-β1–induced α-SMA was mediated by an α3 integrin-dependent increase in integrin-linked kinase (ILK). Src phosphorylation of β-catenin and consequent p-β-catenin-Y654/p-Smad2 transcriptional complex underlies the transcriptional up-regulation of ILK. Kidney fibrosis after unilateral ureteric obstruction or ischemia reperfusion was increased in proximal tubule E-cadherin–deficient mice in comparison to that of E-cadherin intact control mice. The exacerbation of fibrosis was explained by the α3 integrin-dependent increase of ILK, β-catenin nuclear translocation, and α-SMA/proximal tubular–specific Cre double positive staining in proximal tubular epithelial cell. These studies delineate a nonconventional integrin/ILK signaling by α3 integrin–dependent Src/p-β-catenin-Y654/p-Smad2–mediated up-regulation of ILK through which loss of E-cadherin leads to kidney fibrosis.