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Spin-dependent charge transmission or the so-called chirality-induced spin selectivity (CISS) effect was demonstrated in self-assembled chiral coordinated monolayers. Distinct from the previous CISS phenomenon observed mainly on pure biomolecules, here we expanded this effect to the coordinated complex of chiral biomolecules and metal cations, specifically, cysteine-Cu2+-alanine (Cys/Cu/Ala), in which the complex itself was redox-active. However, the coordinated self-assembled monolayers of cysteine-Cu2+-cysteine did not show any spin-dependent effect. In addition, this phenomenon was explained by developing a theoretical model with spin-orbit coupling. The alanine molecules contributed to multiple transport pathways, leading to experimentally observable spin polarization. Finally, this CISS effect in Cys/Cu/Ala complex was demonstrated to amplify the sensing signal. The enantioselective discrimination efficiency could be improved by controlling the orientation of the external magnetic field.

[Nb(η6-C6H3Me3)2] reacts with ethylenediamine (en) solutions of K4Ge9 in the presence of 18-crown-6 to give [(η6-C6H3Me3)NbHGe6]2- (1) and [(η6-C6H3Me3)NbGe6Nb(η6-C6H3Me3)]2- (2) as their corresponding [K(18-crown-6)]+ salts. The crystalline solids are dark brown, air-sensitive, and sparingly soluble or insoluble in most solvents. The [K(18-crown-6)]+ salts of cluster ions 1 and 2 have been characterized by energy-dispersive X-ray (EDX) analysis, NMR studies, single-crystal X-ray diffraction, and electrospray ionization time-of-flight (ESI-TOF) mass spectrometry studies. Cluster ions 1 and 2 have markedly different [Ge6] moieties: an electron-deficient carborane-like subunit in 1 and a two-center, two-electron cyclohexane-like subunit in 2.

An effective and rapid method for the detection of hydrazine hydrate is urgently needed as a result of its high toxicity and extensive use. Here, copper nanoparticles supported on carbon (written as: Cu NP/C) and copper oxide polycrystalline solids (written as: CuO PS), synthesized by calcining the same metal–organic framework at high temperature, were respectively used as electrode materials for electrochemical sensing hydrazine. The results show that the prepared Cu NP/C exhibits a better performance with a sensitivity of 0.1726 mA (mmol/L)−1, a wider linear range of 0.1–2.4 mM and a lower detection limit of 0.0014 mmol·L−1, compared to the obtained CuO PS. This can be reasonably explained by the lower copper valence state and its interaction with the carbon supports in Cu NP/C. Furthermore, the good selectivity and anti‐interference ability from the Cu NP/C are also acquired for electrochemical detection of hydrazine.

LATERAL ORGAN BOUNDARIES DOMAIN (LBD) genes encode plant-specific transcription factors that participate in regulating various developmental processes. In this study, we genetically characterized PagLBD3 encoding an important regulator of secondary growth in poplar (Populus alba × Populus glandulosa). Overexpression of PagLBD3 increased stem secondary growth in Populus with a significantly higher rate of cambial cell differentiation into phloem, while dominant repression of PagLBD3 significantly decreased the rate of cambial cell differentiation into phloem. Furthermore, we identified 1756 PagLBD3 genome-wide putative direct target genes (DTGs) through RNA sequencing (RNA-seq)-coupled DNA affinity purification followed by sequencing (DAP-seq) assays. Gene Ontology analysis revealed that genes regulated by PagLBD3 were enriched in biological pathways regulating meristem development, xylem development, and auxin transport. Several central regulator genes for vascular development, including PHLOEM INTERCALATED WITH XYLEM (PXY), WUSCHEL RELATED HOMEOBOX4 (WOX4), Secondary Wall-Associated NAC Domain 1s (SND1-B2), and Vascular-Related NAC-Domain 6s (VND6-B1), were identified as PagLBD3 DTGs. Together, our results indicate that PagLBD3 and its DTGs form a complex transcriptional network to modulate cambium activity and phloem/xylem differentiation.

Dechlorination of coal-fired flue gas is a novel approach for realizing zero discharge of desulfurization wastewater. The core principle is to convert the HCl in the flue gas into chloride salt, which will migrate into the fly ash. Pilot-scale experiments were conducted to research the migration and agglomeration of chlorine in actual coal-fired flue gas in a power plant. The results indicate that the HCl removal efficiency in flue gas can rise to 70% at a Na/Cl molar ratio of 7.58 when using NaOH solution with clean water or a ratio of 8.93 when using NaOH solution with desulfurization wastewater. XPS shows that the characteristic peak of chloride in the dechlorinated ash is much more pronounced than that in the original ash. The content of inorganic chloride increases significantly with increasing Na/Cl or the utilization of desulfurization wastewater. SEM–EDS indicates that the various salts agglomerated on the fly ash surface notably increase after dechlorination. The contents of Na, Ca, Mg, Fe and S in the ash increase remarkably, especially with desulfurization wastewater. The chloride salts generated by flue gas dechlorination and the pollutants in the desulfurization wastewater are effectively agglomerated with the fly ash.

Moso bamboo (Phyllostachys edulis) is a fast-growing species with uneven growth and lignification from lower to upper segments within one internode. MicroRNAs (miRNAs) play a vital role in post-transcriptional regulation in plants. However, how miRNAs regulate fast growth in bamboo internodes is poorly understood. In this study, one moso bamboo internode was divided during early rapid growth into four segments called F4 (bottom) to F1 (upper) and these were then analysed for transcriptomes, miRNAs and degradomes. The F4 segment had a higher number of actively dividing cells as well as a higher content of auxin (IAA), cytokinin (CK) and gibberellin (GA) compared with the F1 segment. RNA-seq analysis showed DNA replication and cell division-associated genes highly expressed in F4 rather than in F1. In total, 63 miRNAs (DEMs) were identified as differentially expressed between F4 and F1. The degradome and the transcriptome indicated that many downstream transcription factors and hormonal responses genes were modulated by DEMs. Several miR-target interactions were further validated by tobacco co-infiltration. Our findings give new insights into miRNA-mediated regulatory pathways in bamboo, and will contribute to a comprehensive understanding of the molecular mechanisms governing rapid growth.

In recent years, with the wide application of image data visual extraction technology in the field of industrial engineering, the development of industrial economy has reached a new situation. To explore the interaction between the pellet microstructure and compressive strength, firstly, the pellet microstructure needed for the experiment was obtained using a Leica DM4500P microscope. The area proportions of hematite, calcium ferrite, magnetite, calcium silicate and pore in pellet microstructure were extracted by visual extraction technology of image data. Moreover, the relationship between the area proportions of mineral components and compressive strength was established by backpropagation neural network (BPNN), generalized regression neural network (GRNN) and beetle antennae search-generalized regression neural network (BAS-GRNN) algorithms, which proves that the pellet microstructure can be used as the prediction standard of compressive strength. The errors of BPNN and BAS-GRNN are 5.13% and 3.37%, respectively, both of which are less than 5.5%. Therefore, through data visualization, we are able to discuss the connection between various components of pellet microstructure and compressive strength and provide new research ideas for improving the compressive strength and metallurgical performance of pellet.

Taurine is a sulfur-containing amino acid that plays an important role in glucose homeostasis. However, it remains unknown whether the plasma concentration of taurine affects the risk of later gestational diabetes mellitus (GDM) development. We recruited 398 singleton-pregnancy women and followed up them during the course of pregnancy. We measured the plasma concentrations of taurine based on blood samples collected at nine-week gestation on average and obtained the data regarding both mothers and their infants from medical records. There was a significant increment in the mean value of HOMA-β across the tertiles of plasma taurine in multiparous women rather than in primiparous women. After adjustment for confounders, an increase of plasma taurine was nominally and significantly associated with a decrease risk of GDM; moreover, women with plasma taurine concentrations in the lowest tertile and in the second tertile had a higher risk of GDM than did those with plasma taurine in the top tertile in multiparous women other than primiparous women. Plasma taurine level seems to be associated with insulin secretion in early pregnancy and be more closely associated with β-cell function and the risk of GDM development in multiparas in comparison to primiparas.

Summary Objective Intervertebral disc degeneration (IDD) represents major cause of low back pain. Quercetin (QUE) is one of the approved senolytic agents. In this study, we evaluated the protective effects of QUE on IDD development and its underlying mechanism. Methods Effects of senolytic agent QUE on the viability of nucleus pulposus cells (NPCs) were measured by CCK-8 assays and EdU staining. The senescence associated secreted phenotype (SASP) factors expressions were measured by qPCR, western blot, and ELISA; and NF-κB pathway was detected by immunofluorescence and western blot. Molecular docking was applied to predict the interacting protein of QUE; while Nrf2 was knocked down by siRNAs to confirm its role in QUE regulated senescence phenotype. X-ray, MRI, Hematoxylin-Eosin and Safranin O-Fast green staining were performed to evaluate the therapeutic effects of QUE on IDD in the puncture-induced rat model. Results In in vitro experiments, QUE inhibited SASP factors expression and senescence phenotype in IL-1β-treated NPCs. Mechanistically, QUE suppressed IL-1β induced activation of the NF-κB pathway cascades; it was also demonstrated in molecular docking and knock down studies that QUE might bind to Keap1-Nrf2 complex to suppress NF-κB pathway. In vivo, QUE ameliorated the IDD process in the puncture-induced rat model. Conclusions Together the present work suggests that QUE inhibits SASP factors expression and senescence phenotype in NPCs and ameliorates the progression of IDD via the Nrf2/NF-κB axis, which supports senolytic agent QUE as a potential therapeutic agent for the treatment of IDD.

Sweet corn (Zea mays convar. saccharata var. rugosa) is a major economic vegetable crop. Different sweet corn cultivars vary largely in flavor, texture, and nutrition. The present study performed widely targeted metabolomics analysis based on the HPLC-MS/MS technology to analyze the metabolic profiles in three sweet corn cultivars widely grown in China. A total of 568 metabolites in the three sweet corn cultivars were detected, of which 262 differential metabolites significantly changed among cultivars. Carbohydrates, organic acids, and amino acids were the majority detected primary metabolites. Organic acids were mainly concentrated on shikimate, benzoic acids, and quinic acid with aromatic groups. And the essential amino acids for the human body, methionine and threonine, were highly accumulated in the high-quality cultivar. In addition, phenylpropanoids and alkaloids were the most enriched secondary metabolites while terpenes were low-detected in sweet corn kernels. We found that the flavonoids exist in both free form and glycosylated form in sweet corn kernels. PCA and HCA revealed clear separations among the three sweet corn cultivars, suggesting distinctive metabolome profiles among three cultivars. The differential metabolites were mapped into flavonoid biosynthesis, phenylpropanoid biosynthesis, biosynthesis of amino acids, and other pathways according to the KEGG classification. Furthermore, we identified skimmin, N ′ ,N ″ -diferuloylspermidine, and 3-hydroxyanthranilic acid as the key quality-related metabolites related to grain quality traits in sweet corn. The results suggested variations of metabolic composition among the three cultivars, providing the reference quality-related metabolites for sweet corn breeding.

Molecular modification plays an important role in tuning the packing motif and charge transport in organic semiconductor materials. In particular, electron-withdrawing substituents and functional heteroatoms have seen a recent surge of interest. Here, we modeled four crystal structures of dinaphtho-thieno-thiophene (DNTT) derivatives with the trifluoromethyl (–CF3) group and heteroatoms (O- and N-atoms), and elaborately delineated the impact of intermolecular interactions to establish the relationship between microscopic molecular structures and macroscopic solid-state packing. The effects of –CF3, O-, and N-atom positions on the charge transport properties were systematically investigated via multi-scale theoretical simulations. The results show that the reorganization energy and frontier molecular orbital energy levels are more sensitive to the positions of O- and N-atoms than the –CF3 position. Significantly, the substitution of heteroatoms on the terminal benzene ring can lead to ambipolar materials after introducing –CF3. The cooperative effect of –CF3, O-, and N-atom substitution can transform the molecular packing from herringbone-stacking to π-stacking. The simultaneous introduction of –CF3 in the trans-position and O-, and N-atoms in the terminal benzene ring can bring the most compact packing and more hydrogen bonds. Besides, the transfer integral fluctuation caused by the position of –CF3 is more intense than that of O- and N-atoms, which originated from the long- and short-axis sliding motions that act as “killer” phonon modes. Our work shows that suitable substituent engineering on p-channel materials might simultaneously realize changes in molecular packing and carrier transport, paving the way toward designing higher-performance specific ambipolar transport materials.

Hemicelluloses are effective renewable biopolymers that can be used in many different industrial processes and preparations. In plants, the content of hemicellulose might change with different developmental stages and/or tissues. Thus, in here chemical and structural differences in hemicellulose isolated from the apical, middle and basal segments of sugarcane stem were characterized using chemical techniques. Further, difference in expression levels of genes related to synthesis of hemicelluloses from these three segments were studied by RNA-seq and qRT-PCR etc. The sugarcane hemicellulose backbone was xylose residues connected via β-1,4 glycosidic linkages which was further substituted with arabinose, acetyl and glucuronic acid side chains. Hemicellulose content was higher in the middle and basal segments with less backbone substitutions compared to apical segments. In terms of gene expression, hemicellulose synthesis and modification genes were intensely expressed in middle and basal segments. Taken together, our research describes differences in hemicellulose content and substitutions in sugarcane during xylogenesis, which will increase our knowledge for finding more refined use of sugarcane bagasse.

The inflammatory environment and excessive chondrocyte apoptosis have been demonstrated to play crucial roles in the onset of osteoarthritis (OA). Hydrogen sulfide (H2 S), a gaseous signalling molecule, exerts an inhibitory effect on inflammation and apoptosis in several degenerative diseases. However, the protective effect of H2 S against OA has not been fully clarified, and its underlying mechanism should be examined further. In the current study, the role of endogenous H2 S in the pathogenesis of OA and its protective effects on interleukin (IL)-1β-induced chondrocytes were identified. Our data revealed decreased H2 S expression in both human degenerative OA cartilage tissue and IL-1β-induced chondrocytes. Pretreatment with the H2 S donor sodium hydrosulfide (NaHS) dramatically attenuated IL-1β-induced overproduction of inflammatory cytokines and improved the balance between anabolic and catabolic chondrocyte capacities, and these effects were dependent on PI3K/AKT pathway-mediated inhibition of nuclear factor kappa B (NF-κB). Moreover, mitochondrial dysfunction-related apoptosis was significantly reversed by NaHS in IL-1β-stimulated chondrocytes. Mechanistically, NaHS partially suppressed IL-1β-induced phosphorylation of the mitogen-activated protein kinase (MAPK) cascades. Furthermore, in the destabilization of the medial meniscus mouse model, OA progression was ameliorated by NaHS administration. Taken together, these results suggest that H2 S may antagonize IL-1β-induced inflammation and mitochondrial dysfunction-related apoptosis via selective suppression of the PI3K/Akt/NF-κB and MAPK signalling pathways, respectively, in chondrocytes and may be a potential therapeutic agent for the treatment of OA.

Background Low back pain (LBP) is a very common condition and leads to serious pain, disability, and price tag all over the world. Intervertebral disk degeneration (IDD) is one of the major reasons that contributed to LBP. The levels of interleukin 1 beta (IL-1β) increase significantly in degenerative disks. IL-1β also accelerates IDD. Sinapic acid (SA) has the effect of anti-inflammatory, antioxidant and antimicrobial. However, the effect of SA on IDD has never been studied. Therefore, the aim of this study was to figure out whether SA has protective effect on nucleus pulposus (NP) cells and further explore the possible underlying mechanism. Methods The nucleus pulposus (NP) tissues of rats were collected and cultured into NP cells. The NP cells were stimulated by IL-1β and treated with SA. In vitro treatment effects were evaluated by ELISA, Western blot assay, immunofluorescence, TUNEL method and real-time PCR. We conducted percutaneous needle puncture in the rat tail to build intervertebral disk degeneration model and treated rats with SA. In vivo treatment effects were evaluated by hematoxylin and eosin (HE) and safranin O (SO) staining and magnetic resonance imaging (MRI) method. Results Our results showed that SA not only inhibited apoptosis but also suppressed inflammatory mediators including nitric oxide (NO), prostaglandin E2 (PGE2), cyclooxygenase 2 (COX-2), inducible nitric oxide synthase (iNOS) interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) in IL-1β-stimulated NP cells. As to extracellular matrix (ECM), SA could increase collagen II and aggrecan levels and reduce the expression of MMP13 and ADAMTS5 during the stimulation of IL-1β. Furthermore, SA could activate nuclear factor-erythroid 2-related factor-2 (Nrf2) to inhibit nuclear factor κB (NF-κB) induced by IL-1β. Nrf2 knockdown partly reduced the protective effect of SA on NP cells. Correspondingly, SA ameliorated IDD by promoting Nrf2 expression. In vivo results also showed that SA could delay the progression of IDD. Conclusion In conclusion, we demonstrated that SA could protect the degeneration of NP cells and revealed the underlying mechanism of SA on Nrf2 activation in NP cells.

Background Microtubules pull chromosomes apart during cell mitosis and take part in cell division, Inhibiting the formation of spindle microtubules during mitosis has become one of the current anti-tumor research strategies. Earlier studies have found that the family with sequence similarity 172, member A (FAM172A) can significantly inhibit the proliferation of human colorectal cancer cell line LOVO cells and promote apoptosis. The purpose of this study was to investigate the biological effects of FAM172A on liver cancer cells and the interaction mechanism with tubulin. Methods Use STRING software predicted the interactions between FAM172A and β-tubulin, and verify by immunoprecipitation. Real-Time qPCR was used to determine the expression levels of β-tubulin in liver cancer cell line HepG2, western blot was performed to detect protein expression levels. Immunofluorescence experiment to detect the distribution, shape and the dynamic behavior of depolymerization-aggregation of β-tubulin in cells. MTT, wound healing and Transwell assay were employed to determine cell proliferation, migration and invasion respectively. Flow cytometry was conducted to determine cell cycle and apoptosis. Results There is no interactions between FAM172A and β-tubulin. We determined that when FAM172A was up-regulated or down-regulated, the mRNA and protein levels of β-tubulin did not change significantly (P>0.05). Furthermore, the distribution, shape of β-tubulin in cells, and the dynamic behavior of depolymerization-aggregation was not affected. After FAM172A overexpression, the migration and invasion of HepG2 cells were significantly inhibited (P

In recent years, metal isolated site catalysts with the high exposure and maximized availability of metal species provide a new route to boost the oxygen reduction performance. However, in the abse...

Investigation of the clear structure–property relationship and microscopic mechanism of thermally activated delayed fluorescence (TADF) emitters with high emission quantum yield is a direction wort...

NAC (NAM, AFAT and CUC) proteins play necessary roles in plant response to environmental stresses. However, the functional roles of NAC genes in moso bamboo (Phyllostachys edulis), an essential economic perennial woody bamboo species, are not well documented. In this study, we retrieved 152 PeNAC genes from the moso bamboo V2 genome, and PeSNAC-1 was isolated and functionally characterized. PeSNAC-1 was localized in the nucleus and had no transactivation activity in yeast. PeSNAC-1 extremely expressed in rhizome and young roots (0.1 and 0.5 cm) and was significantly induced by drought and salt treatments but repressed by abscisic acid (ABA), methyl jasmonate and high temperature (42 °C) in moso bamboo. Under water shortage and salinity conditions, survival ratios, Fv/Fm values, physiological indexes such as activities of superoxide dismutase, peroxidase and catalase and contents of malondialdehyde, H2O2 and proline were significantly higher in transgenic rice than the wild type, which suggests enhanced tolerance to drought and salt stress in PeSANC-1 overexpressed plants. Transcript levels of Na+/H+ antiporter and Na+ transporter genes (OsSOS1, OsNHX1 and OsHKT1;5), ABA signaling and biosynthesis genes (OsABI2, OsRAB16, OsPP2C68, OsLEA3-1, OsLEA3, OsNCED3, OsNCED4 and OsNCED5) and ABA-independent genes (OsDREB1A, OsDREB1B and OsDREB2A) were substantially higher in transgenic as compared with the wild type. Moreover, protein interaction analysis revealed that PeSNAC-1 could interact with stress responsive PeSNAC-2/4 and PeNAP-1/4/5 in both yeast and plant cells, which indicates a synergistic effect of those proteins in regulating the moso bamboo stress response. Our data demonstrate that PeSNAC-1 likely improved salt and drought stress tolerance via modulating gene regulation in both ABA-dependent and independent signaling pathways in transgenic rice. In addition, PeSNAC-1 functions as an important positive stress regulator in moso bamboo, participating in PeSNAC-1 and PeSNAC-2/4 or PeSNAC-1 and PeNAP-1/4/5 interaction networks.

Phosphoinositide 3-kinase catalytic subunit δ isoform (P110δ) is mainly expressed in white blood cells. It is involved in T and B lymphocyte differentiation, maturation and the neutrophil chemotaxis process. Apolipoprotein E (ApoE) is an arginine-rich alkaline protein, which is present in plasma chylomicron, low-density lipoprotein and very low-density lipoprotein. The present study aimed to determine the effects of P110δ deletion on myocarditis in ApoE−/− mice. A mouse model of ApoE and P110δ double deletion was initially constructed; hematoxylin and eosin (H&E) staining was performed to detect the histological alterations in the mouse myocardium. Systolic and diastolic alterations, and alterations in the left ventricular fractional shortening (LVFS) and left ventricular ejection fraction (LVEF) were examined by electrocardiogram. Blood cell of ApoE and P110δ double mice was used to detect changes in white blood cells and monocytes. Western blotting was used to detect the expression levels of apoptosis-associated proteins, whereas flow cytometry was used to detect the percentage of apoptosis. Morphological alterations in myocardial cells were observed under a microscope. The results of polymerase chain reaction demonstrated that double deletion mice were successfully constructed. H&E staining revealed that cells in the ApoE−/− mice were spindle-shaped; however, the nuclei were smaller in the double deletion mice. There was no change in cardiac contraction in normal mice; however, in double deletion mice, the systolic and diastolic contractions were markedly reduced. LVFS and LVEF were decreased compared with in the control group. Blood cell analysis indicated that the content of white blood cells and monocytes in the experimental group was significantly higher than that in the control group. Western blotting demonstrated that the expression levels of apoptotic proteins in double deletion mice were significantly higher compared with in the control group. Flow cytometry revealed that the apoptotic ratio was increased in double deletion mice compared with in the control group (42 vs. 21%). These findings suggested that deletion of P110δ may induce monocyte peritoneal infiltration and increase apoptosis, thus promoting the development of myocarditis.

Background Cancers of the gastrointestinal (GI) tract and its associated excretory glands are one of the most common causes of cancer-related death worldwide, and these patients are more likely to developing nosocomial infections due to immunodeficiency. Objective To explore the bacterial profile, antibiotic resistance pattern, and prognostic factors of nosocomial infections in hospitalized GI cancer patients. Methods All electronic medical records of nosocomial infection episodes in hospitalized GI cancer patients were retrospectively reviewed. In-hospital mortality was used to evaluate the prognosis of patients. Mann-Whitney test, Chi-square test, and binary logistic regression analysis were used to identify potential risk factors for in-hospital mortality. P-values

The icosahedral [M@Pb12 ]3- (M=Co(1), Rh(2), Ir(3)) cluster ions were prepared from K4 Pb9 and Co(dppe)Cl2 (dppe=1,2-bis(diphenylphosphino)ethane)/[Rh(PPh3 )3 Cl]/[Ir(cod)Cl]2 (cod=1,5-cyclooctadiene), respectively, in the presence of 18-crown-6/ 2,2,2-cryptand in ethylenediamine/toluene solvent mixtures. The [K(2,2,2-cryptand)]+ salt of 1 and the [K(18-crown-6)]+ salt of 3 were characterized via X-ray crystallography; the ions 1 and 3 are isostructural and isoelectronic to the [Rh@Pb12 ]3- (2) ion as well as to the group 10 clusters [M'@Pb12 ]2- (M'=Ni, Pd, Pt). The ions are all 26-electron clusters with near perfect icosahedral Ih point symmetry. Clusters 1-3 show record downfield 207 Pb NMR chemical shifts due to σ-aromaticity of the cluster framework. Calculated and observed 207 Pb NMR chemical shifts and 207 Pb-x M J-couplings (x M=59 Co, 103 Rh, 193 Ir) are in excellent agreement and DFT analysis shows that the variations of 207 Pb NMR chemical shifts for the [M@Pb12 ]2, 3- ions (M=Co, Rh, Ir, Ni, Pd, Pt) are mainly governed by the perpendicularly oriented σ11 component of the chemical shift anisotropy tensor. The laser desorption ionization time-of-flight (LDI-TOF) mass spectra contain the molecular ions as well as several new gas phase clusters derived from the parents. The DFT-minimized structures of these ions are described.

Most of the biomedical materials printed using 3D bioprinting are static and are unable to alter/transform with dynamic changes in the internal environment of the body. The emergence of four-dimensional (4D) printing addresses this problem. By preprogramming dynamic polymer materials and their nanocomposites, 4D printing is able to produce the desired shapes or transform functions under specific conditions or stimuli to better adapt to the surrounding environment. In this review, the current and potential applications of 4D-printed materials are introduced in different aspects of the biomedical field, e.g., tissue engineering, drug delivery, and sensors. In addition, the existing limitations and possible solutions are discussed. Finally, the current limitations of 4D-printed materials along with their future perspective are presented to provide a basis for future research.

There is an increasing demand for effective noninvasive diagnosis against common pulmonary diseases, which are rising sharply due to the serious air pollution. Human neutrophil elastase (HNE), a typical protease highly involved in pulmonary inflammatory diseases and lung cancer, is a potential predictor for disease progression. Currently, few of the HNE-targeting probes are applicable in vivo due to the limitation in sensitivity and biocompatibility. Herein, we reported the achievement of in vitro detection and in vivo imaging of HNE by incorporating the HNE-specific peptide substrate, quantum dots (QDs), and organic dyes into the fluorescence resonance energy transfer (FRET) system. The refined nanoprobe, termed QDP, could specifically measure the HNE with excellent sensitivity of 7.15 pM in aqueous solution and successfully image the endogenous and exogenous HNE in living cells. In addition, this nanoprobe enabled HNE imaging in mouse models of lung cancer and acute lung injury, and the HNE activity at high temporal and spatial resolution was continuously monitored. Most importantly, QDP successfully discriminated the serums of patients with lung diseases from those of the healthy controls based on the HNE activity determination. Overall, this study demonstrates the advantages of a FRET-system-based nanoprobe in imaging performance and provides an applicable tool for in vivo HNE detection and pulmonary disease diagnosis.

Polymerized high internal phase emulsion (polyHIPE) monoliths have attracted much attention because of their ease of preparation, precise control of porous structure and useful properties. For many applications, such as chromatographic separation media, reactivity or absorptivity, post-modification of surface functional groups is required to achieve the desired functionality. However, for fluoro-polymers, it has been a challenge to fabricate high-performance foams with uniform porous structures using HIPE due to the lack of suitable surfactants to stabilize the fluorinated emulsions. In our work, we proposed a bottom-up approach where the same surfactant that stabilized the water droplets within the oil phase was used to control the solid foam surface chemistry. We employed reversible addition–fragmentation chain transfer living radical polymerization to synthesize amphiphilic-fluorinated macrosurfactant (mPEG5K-PHFBMA) to stabilize water-in-oil (W/O) HIPE. Using hexafluorobutyl methacrylate as the oil-phase monomer and divinylbenzene as the cross-linking agent, we achieved a one-pot preparation of polyHIPEs based upon poly(ethylene glycol) (PEG) with biocompatible pore surfaces and potential use in tissue engineering. The effects of amphiphilic macromolecular surfactant concentration, PHFBMA block length and initiator oil/water solubility on the emulsion droplet size, pore morphology, porous surface performance and mechanical properties were studied. The PEG modification on porous surface in the polyHIPE was also confirmed by a contact angle test and water uptake experiment. It was found that short-chain fluorinated materials demonstrated very little bioaccumulation potential and consequently better environmental safety attributes. The addition of PEG gave good biocompatibility, and the properties of these porous materials may have great potential in cell tissue engineering applications.

Considerable progress in developing flat-rolled steel grades has been made by the Chinese steel industry over the recent two decades. The increasing demand for high-performance products to be used in infrastructural projects as well as in production of consumer and capital goods has been driving this development until today. The installation of state-of-the-art steel making and rolling facilities has provided the possibility of processing the most advanced steel grades. The production of high-performance steel grades relies on specific alloying elements of which molybdenum is one of the most powerful. China is nearly self-sufficient in molybdenum supplies. This paper highlights the potential and advantages of molybdenum alloying over the entire range of flat-rolled steel products. Specific aspects of steel property improvement with respect to particular applications are indicated.

Osteoarthritis is a chronic degenerative disease characterized by cartilage destruction. It is the fourth most disabling disease worldwide and is currently incurable. Inflammation and extracellular matrix (ECM) degradation are considered to be substantial reasons for accelerating the progression of OA. β-Hydroxyisoamylshikonin (β-HIVS) is a natural naphthoquinone compound with anti-inflammatory and antioxidant activity. However, the effect of β-HIVS on OA is still unclear. In this study, we found that β-HIVS can down-regulate the expression of NO, PEG2, IL-6, TNF-α, COX-2, and iNOS, suggesting its anti-inflammatory effects in chondrocytes; we also found that β-HIVS may down-regulate the expression of ADAMTS5 and MMP13 and up-regulate the expression of aggrecan and collagen II to inhibit the degradation of ECM. Mechanistically, β-HIVS inhibited the NFκB pathway by activating the Nrf2/HO-1 axis, thereby exerting its anti-inflammatory and inhibitory effects on ECM degradation. In vivo experiments also proved the therapeutic effects of β-HIVS on OA in mice, and Nrf2 is the target of β-HIVS. These findings indicate that β-HIVS may become a new drug for the treatment of OA.

Intervertebral disc degeneration (IDD) has been reported to be a major cause of low back pain. Stachydrine (STA) is present in the fruit juice of the Citrus genus and Leonurus heterophyllus, in non-negligible concentrations. In our study, we examined the protective effects of STA against IDD development as well as its underlying mechanism of action using both in vitro and in vivo experiments. STA exerted protective effects on the anabolism and catabolism of the extracellular matrix (ECM) in IL-1β-treated NPCs and inhibited the expression of pro-inflammatory factors in vitro. Mechanistically, STA suppressed the IL-1β-induced activation of PI3K/Akt/NF-κB signalling pathway cascades. Moreover, it was also demonstrated in molecular docking studies that STA has strong binding abilities to PI3K. Furthermore, STA ameliorated the progression of the IDD process in vivo in the puncture-induced rat model. In summary, our findings demonstrated that STA ameliorates the progression of IDD via the PI3K/Akt/NF-κB signalling pathway, which makes STA a promising therapeutic agent for the treatment of IDD.

Abstract Electrocatalytic glucose oxidation is a very important reaction in glucose fuel cell and medical diagnosis, which is limited by sluggish reaction kinetics and low diffusion coefficient. Herein, a composite (donated as Ni6/AB) consisting of atomically precise nickel catalyst with defined crystal structure [Ni6(SC12H25)12] and acetylene black(AB) has been initiated as a novel and high-efficient non-noble metal catalyst for the electrochemical oxidation of glucose benefiting from its high exposure of active sites and increased electron/mass transport. The present Ni6/AB composites display the onset potential of +1.24 V and the maximum current density of 5 mA cm−2 at the potential of +1.47 V in the electrolyte of 0.1 M KOH with 5 mM glucose. This electrochemical performance is much superior to the alone nickel catalysts, acetylene black, and previous reported nanomaterials. Furthermore, the obtained Ni6/AB composites are also expected to find important application in the electrochemical detection of glucose due to its high electrochemical performance. The sensitivity and the detection of limit are determined to be 0.7709 mA cm−2 mM−1 and 1.9 μM, respectively. Our study demonstrates that atomically precise nickel catalysts on acetylene black could be potential promising materials for next-generation energy devices and electrochemical sensors. Graphical abstract

Scope Peanut stem and leaf (PSL), a traditional Chinese medicine, is widely used as a dietary supplement to improve sleep quality, however, the underlying mechanism is unclear. Here, we aimed to determine whether active compounds in PSL extract exert their effects by mediating neuronal excitability. Methods and results Aqueous PSL extract (500 mg/kg BW) increased the duration of total sleep (TS), slow wave sleep (SWS) and rapid eye movement sleep (REMS) in BALB/c mice after 7 and 14 continuous days of intragastric administration. Two PSL extract components with flavonoid-like structures: 4',7-di-O-methylnaringenin (DMN, 61 μg/kg BW) and 2'-O-methylisoliquiritigenin (MIL, 12 μg/kg BW), showed similar effects on sleep in BALB/c mice. Moreover, incubation with DMN (50 μM) and MIL (50 μM) acutely reduced voltage-gated sodium and potassium currents and suppressed the firing of evoked action potential in mouse cortical neurons, indicating the inhibition on neuronal excitability. Meanwhile, RNA-seq analysis predicted the potential regulation of voltage-gated channels, which is according with the molecular docking simulation that both MIL and DMN can bind to Nav 1.2. Conclusions DMN and MIL are the active ingredients of PSL that improve sleep quality, suggesting that PSL promotes sleep by regulating the excitability of neurons. This article is protected by copyright. All rights reserved.

The study aimed to compare the pharmacokinetic properties of quercitrin, astragalin, afzelin and taxifolin, four major bioactive components of Polygonum orientale inflorescence extracts, between sham-operated and myocardial ischemia-reperfusion injury (MIRI) rats.Rats were divided into two groups: MIRI model and sham-operated. The blood samples were collected according to the time schedule. The levels of quercitrin, astragalin, afzelin and taxifolin in the plasma at designated time points were determined using an HPLC-MS/MS method. Various pharmacokinetic parameters were estimated from the plasma concentration versus time data using non-compartmental methods. After the administration of the Chinese herb Polygonum orientale inflorescence extracts, the Cmax, AUC, as well as MRT, increased, while CL decreased, in MIRI model compared to the sham-operated animals.These results suggest that the pathological damage of ischemia-reperfusion had a significant impact on the pharmacological effects of Polygonum orientale inflorescence extracts on ischemic heart disease.The method had been successfully applied to evaluate the pharmacokinetics of quercitrin, astragalin, afzelin and taxifolin in rat plasma after the oral administration of Chinese herb Polygonum orientale inflorescence extracts in rats.

Due to the resource shortage of indium, the application of 10 wt%- tin doped indium oxide (10 wt%- ITO) with 74.4 wt% of indium is restricted in the field of flat panel display. A new ternary compound TCO material with 53.8 wt% of indium (35 wt%- ITO) was prepared by In2O3-35 wt% SnO2 powders, whose microstructure and properties were studied in comparison to 10 wt%- ITO. The research findings show that: (1) The phase composition of 35 wt%- ITO target is mainly In4Sn3O12 and In2SnO5, without In2O3: Sn phase for 10 wt%- ITO; (2) When films possess the strong crystalline structure, the photoelectric properties of 35 wt%- ITO films are superior to 10 wt%- ITO. In addition, the crystalline structure of 35 wt%- ITO films could be changed from In4Sn3O12 + amorphous to In4Sn3O12 + In2O3 by annealing, but for 10 wt%- ITO, only the crystallinity is changed.

As one member of PTPs, Src homology-2 domain-containing protein tyrosine phosphatase 1 (SHP1) is mainly restricted to hematopoietic and epithelial cells and widely accepted as a convergent node for oncogenic cell-signaling cascades. Developing efficient methods for rapidly tracing and inhibiting the SHP1 activity in complex biological systems is of considerable significance for advancing the integration of diagnosis and treatment of related disease. On this goal, we designed and synthesized five 2-phenyl-1,3,4-thiadiazole derivatives (PT2, PT5, PT8, PT9 and PT10) here basing on the reported SHP1 inhibitors (PT1, PT3, PT4, PT6 and PT7) with planarity structure. The photophysical properties and inhibitory activities of these 2-phenyl-1,3,4-thiadiazole derivatives (PT1 ‒ PT10) for SHP1 were thoroughly studied from theoretical aspect and experimental application. The representative compound PT10 exhibited the larger quantum yield than the other molecules because of smaller geometric relaxation and reorganization energy of the excited state, which was consistent with the results from the fluorescence experiments in organic solvent. In addition, PT10 showed selectively fluorescence response for SHP1 activity and low-cytotoxicity on Hela cells. Lastly, it indicated the potential application in two-photon cell fluorescence imaging in the future according to the calculated excellent two-photon absorption properties. In this contribution, we offered the fluorescent and activated molecule PT10 against SHP1 firstly, which achieved the integration of visualization and inhibitory activity of SHP1 preliminarily in enzyme molecular level.

Lignin biosynthesis enzymes form complexes for metabolic channelling during lignification and these enzymes also play an essential role in biotic and abiotic stress response. Cinnamyl alcohol dehydrogenase (CAD) is a vital enzyme that catalyses the reduction of aldehydes to alcohols, which is the final step in the lignin biosynthesis pathway. In the present study, we identified 49 CAD enzymes in five Bambusoideae species and analysed their phylogenetic relationships and conserved domains. Expression analysis of Moso bamboo PheCAD genes in several developmental tissues and stages revealed that among the PheCAD genes, PheCAD2 has the highest expression level and is expressed in many tissues and PheCAD1, PheCAD6, PheCAD8 and PheCAD12 were also expressed in most of the tissues studied. Co-expression analysis identified that the PheCAD2 positively correlates with most lignin biosynthesis enzymes, indicating that PheCAD2 might be the key enzyme involved in lignin biosynthesis. Further, more than 35% of the co-expressed genes with PheCADs were involved in biotic or abiotic stress responses. Abiotic stress transcriptomic data (SA, ABA, drought, and salt) analysis identified that PheCAD2, PheCAD3 and PheCAD5 genes were highly upregulated, confirming their involvement in abiotic stress response. Through yeast two-hybrid analysis, we found that PheCAD1, PheCAD2 and PheCAD8 form homo-dimers. Interestingly, BiFC and pull-down experiments identified that these enzymes form both homo- and hetero- dimers. These data suggest that PheCAD genes are involved in abiotic stress response and PheCAD2 might be a key lignin biosynthesis pathway enzyme. Moreover, this is the first report to show that three PheCAD enzymes form complexes and that the formation of PheCAD homo- and hetero- dimers might be tissue specific.

Nitrogen (N) is one of the abundant and essential elements for plant growth and development, and N deficiency (ND) affects plants at both physiological and transcriptomic levels. Neolamarckia cadamba is a fast-growing woody plant from the Rubiaceae family. However, the physiological and molecular impacts of ND on this species have not been well investigated. Here, we studied how N. cadamba responds to ND under hydroponic conditions. In a physiological aspect, ND led to a reduction in biomass, chlorophyll content, and photosynthetic capacity. ND also impaired the assimilation of N as the activities of glutamine synthetase (GS) and nitrate reductase (NR) were decreased in the root. Interestingly, the lignin content of stem increased progressively during the ND stress. The main transcription factors, the transcription factors that are important to N regulation has been found to be upregulated, including Nodule inception-like protein 7 (NLP7), TGACG motif-binding factor 1 (TGA1), basic helix-loop-helix protein 45 (BHLH45), NAM, ATAF1,2, CUC2 (NAC) transcription factor 43 (NAC43), and basic leucine zipper pattern 44 (bZIP44). The expression of N transporters, such as nitrate transporter 2.4 (NRT2.4), ammonium transporter 3 (AMT3), and amino acid transporter protein 3 (AAP3), was also upregulated. In addition, phosphorus- and calcium-related genes such as phosphate starvation response 2 (PHR2) and cyclic nucleotide-gated ion channel 15 (CNGC15) were expressed more abundantly in response to ND stress. Our results reveal the physiological and molecular mechanisms by which woody plants respond to ND.

Hemicellulose is entangled with cellulose through hydrogen bonds and meanwhile acts as a bridge for the deposition of lignin monomer in the secondary wall. Therefore, hemicellulose plays a vital role in the utilization of cell wall biomass. Many advances in hemicellulose research have recently been made, and a large number of genes and their functions have been identified and verified. However, due to the diversity and complexity of hemicellulose, the biosynthesis and regulatory mechanisms are yet unknown. In this review, we summarized the types of plant hemicellulose, hemicellulose-specific nucleotide sugar substrates, key transporters, and biosynthesis pathways. This review will contribute to a better understanding of substrate-level regulation of hemicellulose synthesis.

Osteoarthritis (OA), a degenerative disorder, is considered to be one of the most common forms of arthritis. Limonin (Lim) is extracted from lemons and other citrus fruits. Limonin has been reported to have anti-inflammatory effects, while inflammation is a major cause of OA; thus, we propose that limonin may have a therapeutic effect on OA. In this study, the therapeutic effect of limonin on OA was assessed in chondrocytes in vitro in IL-1β induced OA and in the destabilization of the medial meniscus (DMM) mice in vivo. The Nrf2/HO-1/NF-κB signaling pathway was evaluated to illustrate the working mechanism of limonin on OA in chondrocytes. In this study, it was found that limonin can reduce the level of IL-1β induced proinflammatory cytokines such as INOS, COX-2, PGE2, NO, TNF-α, and IL-6. Limonin can also diminish the biosynthesis of IL-1β-stimulated chondrogenic catabolic enzymes such as MMP13 and ADAMTS5 in chondrocytes. The research on the mechanism study demonstrated that limonin exerts its protective effect on OA through the Nrf2/HO-1/NF-κB signaling pathway. Taken together, the present study shows that limonin may activate the Nrf2/HO-1/NF-κB pathway to alleviate OA, making it a candidate therapeutic agent for OA.

Hypochloric acid (HOCl) plays a vital role in the natural defense system, but abnormal levels of it can cause cell damage, accelerated human aging, and various diseases. It is of great significance to develop new probes for detecting HOCl in biosystems nondestructively and noninvasively. The purpose of this work is to explore new chemical modification strategies of two-photon excitation fluorescence (TPEF) probes to improve the poor water solubility and low efficiency in imaging applications. Nil-OH-6 has a two-photon absorption cross-section value as high as 243 GM and attains a good quantum yield of 0.49. In addition, the modification of terminal groups with different azetidine-heterospirocycles or N,N-dialkyl fused amino groups to Nile Red can effectively improve the fluorescence efficiency as well as increase the solubility to some extent. This study provides some strategies to simultaneously improve the fluorescence performance and solubility of these two-photon probes and, hence, reliable guidance and a foundation for the subsequent synthesis of TPEF probes based on Nile Red.

Background Nitrogen, as a limiting factor for net primary productivity in grassland ecosystems, is an important link in material cycles in grassland ecosystems. However, the nitrogen assimilation efficiency and mechanisms of grassland plants under grazing disturbance are still unclear. This study investigated Stipa breviflora desert steppe which had been grazed for 17 years and sampled the root system and leaf of the constructive species Stipa breviflora during the peak growing season under no grazing, light grazing, moderate grazing and heavy grazing treatments. The activities of enzymes related to nitrogen assimilation in roots and leaves were measured. Results Compared with no grazing, light grazing and moderate grazing significantly increased the activities of nitrate reductase (NR), glutamine synthetase (GS), glutamic oxaloacetic transaminase (GOT) and glutamic pyruvate transaminase (GPT) in leaves, and GS, GOT and GPT in roots of Stipa breviflora, while heavy grazing significantly decreased the activities of GS in leaves and NR in roots of Stipa breviflora. NR, GOT and GPT activities in leaves and roots of Stipa breviflora were positively correlated with nitrogen content, soluble protein, free amino acid and nitrate content. Conclusions Grazing disturbance changed the activities of nitrogen assimilation related enzymes of grassland plants, and emphasized that light grazing and moderate grazing were beneficial for nitrogen assimilation by grassland plants. Therefore, establishing appropriate stocking rates is of great significance for material flows in this grassland ecosystem and for the stability and sustainable utilization of grassland resources.

An accurate sensor to rapidly determine the glucose concentration is of significant importance for the human body health, as diabetes has become a very high incidence around the world. In this work, copper nanoparticles accommodated in porous carbon substrates (Cu NP@PC), synthesized by calcinating the filter papers impregnated with copper ions at high temperature, were designed as the electrode active materials for electrochemical sensing of glucose. During the formation of porous carbon, the copper nanoparticles spontaneously accommodated into the formed voids and constituted the half-covered composites. For the electrochemical glucose oxidation, the prepared Cu NP@PC composites exhibit much superior catalytic activity with the current density of 0.31 mA/cm2 at the potential of 0.55 V in the presence of 0.2 mM glucose. Based on the high electrochemical oxidation activity, the present Cu NP@PC composites also exhibit a superior glucose sensing performance. The sensitivity is determined to be 84.5 μA /(mmol.L) with a linear range of 0.01 ~ 1.1 mM and a low detection limit (LOD) of 2.1 μmol/L. Compared to that of non-porous carbon supported copper nanoparticles (Cu NP/C), this can be reasonable by the improved mass transfer and strengthened synergistic effect between copper nanoparticles and porous carbon substrates. Supplementary Information The online version contains supplementary material available at 10.1186/s11671-021-03579-y.

A novel imidazolium derivative (GITag) shows superior ionisation and consequently allows increased mass spectrometric detection capabilities of oligosaccharides and N-glycans. Here we demonstrate that human serum samples can be directly labelled by GITag on a MALDI target plate, abrogating prevalently required sample pretreatment or clean-up steps.